P. L. Lewin

Publication List Details

Period

1995 - 2009

Number

473

Co-Authors

Effect of field-dependent mobility on current density and dynamics of space charge in polyethylene (2009)

Zhao, J, Xu, Z, Chen, G, Lewin, P L

Transient space charge within polyethylene has been simulated based on a bipolar charge transport model with a constant mobility. Initial results are in good agreement with those previously reported....

Partial Discharge Measurements for Spherical Cavities within Solid Dielectric Materials under Different Stress and Cavity Conditions (2009)

Illias, H, Chen, G, Lewin, P L

The measurement of partial discharge is used in the performance assessment of insulation systems of high voltage components. This paper describes the development of a test object consisting of a...

Two Dimensional Studies of Trichel Pulses in Air Using the Finite Element Method (2009)

Tran, T N, Golosnoy, I, Lewin, P L, Georghio, G E

The formation of Trichel pulses using two dimensional axisymmetric finite element (FE) simulations is presented in this paper. The hydrodynamic drift-diffusion approximation is used to model the...

Raman microprobe analysis and ageing in dielectrics (2009)

Freebody, N A, Vaughan, A S, Lewin, P L

Subsurface voids in samples of electrically stressed low density polyethylene (LDPE) were analysed using confocal Raman microprobe spectroscopy (CRMS). An optical depth profiling technique was used...

Experimental Studies on Surface Discharge Dynamics and Decay under Different Voltage Waveforms and Electrode Shapes (2009)

Tran, T. N., Lewin, P. L., Wilkinson, J. S., Swingler, S. G., Coventry, P. F.

This paper studies the development and decay of surface discharge under various voltage waveforms and electrode shapes in air at atmospheric pressure. The electro-optical Pockels method is utilised...

Lightning Impulse Ageing of HV Cable Insulation (2009)

Dao, N L, Lewin, P L, Swingler, S G

Lightning impulses can lead to accelerated ageing of extruded cables. Electrical behaviour of a dielectric material when experiencing a lightning impulse is different to that for DC or power...

Frequency Domain Modeling of High Voltage Transformers Using a Nonlinear Least-Square Estimation Technique (2009)

Mohamed, R, Lewin, P L

The development of transformer models can be achieved based on experimental frequency response measurements providing access to the windings is available and the physical dimensions are known in...

Modeling of Surface Charge Decay in a Spherical Cavity within a Solid Dielectric Material using Finite Element Analysis (2009)

Illias, H, Chen, G, Lewin, P L

The modelling of cavity surface charge decay through conduction along the cavity wall using the Finite Element Analysis (FEA) method is presented in this paper. A field-dependent cavity surface...

Electric field effects on boiling heat transfer of liquid nitrogen (2009)

Wang, P, Lewin, P L, Swaffield, D J, Chen, G

This paper describes an experimental study into the influence of a d.c. uniform electric field on boiling heat transfer characteristics of liquid nitrogen. The electric field effect on the onset of...

An upper limb model using FES for stroke rehabilitation (2009)

Freeman, C., Hughes, A.M., Burridge, J., Chappell, P., Lewin, P.L., Rogers, E.

A model of the upper limb is developed in which the forearm is constrained to lie in a horizontal plane and electrical stimulation is applied to the triceps muscle. Identification procedures are...

Modelling of Partial Discharge Activity in Different Spherical Cavity Sizes and Locations within a Dielectric Insulation Material (2009)

Illias, H A, Chen, G, Lewin, P L

The pattern of partial discharge (PD) occurrence at a defect site within a solid dielectric material is influenced by the conditions of the defect site. This is because the defect conditions, mainly...

Modelling of Partial Discharge Activity in Different Spherical Cavity Sizes and Locations within a Dielectric Insulation Material (2009)

Illias, H A, Chen, George, Lewin, P. L.

The pattern of partial discharge (PD) occurrence at a defect site within a solid dielectric material is influenced by the conditions of the defect site. This is because the defect conditions, mainly...

Feasibility of iterative learning control mediated by functional electrical stimulation for reaching after stroke (2009)

Hughes, A.M., Freeman, C.T., Burridge, J.H., Chappell, P.H., Lewin, P.L., Rogers, E.

BACKGROUND: An inability to perform tasks involving reaching is a common problem following stroke. Evidence supports the use of robotic therapy and functional electrical stimulation (FES) to reduce...

Partial Discharge Estimation in a High Voltage Transformer Using a Multi Signal Decomposition Technique (2009)

Mohamed, R, Lewin, P L, Chen, G

A practical technique is introduced to determine the possible high frequency oscillations generated by a Partial Discharge (PD) source within a high voltage transformer. The approximation of the...

Transforming Europe’s Electricity Supply – An Infrastructure Strategy for a Reliable, Renewable and Secure Power System (2009)

Lewin, P L, Altus, J, Amaratunga, G, Belmans, R, Blom, J, Frank, H, ...

European energy policy seeks to achieve a substantially increased contribution from renewable sources of electricity, and the creation of a pan-European competitive electricity market. The existing...

Upper limb rehabilitation of stroke participants using electrical stimulation: changes in tracking and EMG timing (2009)

Hughes, A.M., Freeman, C.T., Burridge, J.H., Chappell, P.H., Lewin, P.L., Rogers, E.

A summary is presented of the tracking and surface electromyographic (EMG) results obtained using a robotic workstation that was designed and built for use by stroke participants in order to improve...

Design and control of an upper arm FES workstation for rehabilitation (2009)

Freeman, C., Hughes, A.M., Burridge, J., Chappell, P., Lewin, P.L., Rogers, E.

An overview is provided of the design, operation and performance of an experimental test facility that has been developed for stroke rehabilitation. The aim of the system is to improve sensory-motor...

Partial Discharge Modelling in a Spherical Cavity within a Dielectric Insulation Material as a Function of Frequency (2009)

Illias, H A, Chen, G, Lewin, P L

The measurement of partial discharge (PD) is used in the performance assessment of an insulation system in high voltage components. Through modeling the discharge process a better understanding of...

Electric Field Interaction in the Inter-Phase Region of Transformers (2009)

Mitchinson, P M, Lewin, P L, Jarman, P N

Large three-phase power transformers normally consist of three cylindrical coil sets (phase windings) assembled side by side in line. The high voltage winding of each phase is generally the outermost...

Partial Discharge Location in High Voltage Transformers (2009)

Mohamed, R, Lewin, P L

Partial discharge (PD) location is a common problem within Power Transformers diagnostics and is important for assessing the severity of any detected fault. The technique presented in this paper is...

Use of Finite Element Analysis to Obtain Thermal Ratings for High Voltage Cable Joint Bays (2009)

Pilgrim, J A, Swaffield, D J, Lewin, P L, Larsen, S T, Payne, D

Recent computational advances have increased the viability of using numerical modelling techniques such as finite element analysis (FEA) to compute the rating of cable circuits. Such analysis has...

Use of Machine Learning for Partial Discharge Discrimination (2009)

Hao, L, Lewin, P L, Swingler, S G

Partial discharge (PD) measurements are an important tool for assessing the condition of power equipment. Different sources of PD have different effects on the insulation performance of power...

Towards a More Flexible Rating Method for Cables In Tunnels (2009)

Pilgrim, J A, Swaffield, D J, Lewin, P L, Larsen, S T, Payne, D

In recent years the use of cable tunnels in large urban areas has become more popular, with the additional capital cost becoming increasingly acceptable in light of the growing difficulties incurred...

Effects of Lightning Impulses on the Dielectric Properties of HDPE (2009)

Dao, N L, Lewin, P L, Swingler, S G

Impulse over-voltages are very common phenomena in electric power systems. Switching impulses are created by switching surges or local faults while lightning impulses are due to lightning strikes to...

Effects of modelling assumptions on the rating calculation for externally forced cooled high-voltage cables (2009)

Swaffield, D J, Lewin, P L, Payne, D, Larsen, S T

To increase the rating of a high-voltage cable circuit the cable group can be externally forced cooled, using additional coolant pipes in proximity to the buried cable group. This complicates...

Boiling heat transfer of liquid nitrogen in the presence of electric fields (2009)

Wang, P, Lewin, P L, Swaffield, D J, Chen, G

An experimental study has been undertaken to determine the influence of a d.c. uniform electrical field on boiling heat transfer of liquid nitrogen (LN2). A copper block electrode with temperature...

Lightning Impulse Ageing of HDPE (2009)

Dao, N L, Lewin, P L, Swingler, S G

This work is concerned with the hypothesis that lightning impulses can lead to accelerated ageing of extruded polymeric cables. The behaviour of an insulation material when suffering lightning...

Assessment of the Impact of Joint Bays on the Ampacity of High Voltage Cable Circuits (2009)

Pilgrim, J A, Swaffield, D J, Lewin, P L, Larsen, S T, Payne, D

Improvements in the cost and availability of computational power in recent years has led to numerical techniques such as finite element analysis (FEA) becoming viable for cable rating calculations....

Iterative Learning Control as an Intervention Aid to Stroke (2008)

C. T. Freeman, J. H. Burridge, P. L. Lewin, E. Rogers

Incidence of stroke in the UK is approximately 100,000 new cases each year. One third of patients will not survive the first year and another third will make a full recovery. Half of all acute stroke...

Phase Resolved Partial Discharge Identification using a Support Vector Machine (2008)

Hao, L, Lewin, P L

Partial discharge (PD) has a significant effect on the insulation performance of power apparatus in both transmission and distribution networks of power systems. Insulation performance and properties...

Evaluation of Partial Discharge Denoising using the Wavelet Packets Transform as a Preprocessing Step for Classification (2008)

Evagorou, D, Kyprianou, A, Lewin, P L, Stavrou, A, Efthymiou, V, Georghiou, G E

The identification of Partial Discharges in high voltage equipment has emerged as one of the most effective condition monitoring methods for assessing the integrity of the equipment under test. The...

Modeling of Partial Discharges from a Spherical Cavity within a Dielectric Material under Variable Frequency Electric Fields (2008)

Illias, H A, Chen, G, Lewin, P L

Partial discharge (PD) is a discharge event that does not bridge the electrodes within an electrical insulation system under high voltage stress. In high voltage components, the measurement of...

Modeling and Parameter Estimation of High Voltage Transformer Using Rational Transfer Function State Space Approach (2008)

Mohamed, R, Markovsky, I, Lewin, P L

Parameter estimation is an important technique for modeling of a high voltage transformer under wide frequency range. The complexity of the winding makes the system so complicated that a model of the...

The Effect of Voltage Waveform on Phase-Resolved Electroluminescence Measurements (2008)

Mohd Ariffin, A, Lewin, P L, Mills, D H, Dodd, S J

Space charge plays a significant role in long term electrical degradation of polymeric insulation in high voltage cables and consequently there is growing interest in the measurement of the energy...

Numerical Modelling of Positive Surface Streamer in Air (2008)

Tran, T N, Lewin, P L, Golosnoy, I O, Georghiou, G E

The development of a positive surface streamer in air at atmospheric pressure is numerically modelled by solving the coupled continuity and Poisson’s equations. The geometry includes a 100 μm...

Continuous On-line Monitoring of Partial Discharges in High Voltage Cables (2008)

Y Tian, P L Lewin, J S Wilkinson, S J Sutton, S G Swingler

Abstract: This paper reviews data acquisition, transmission and processing methodologies for continuous on-line monitoring of partial discharges in power cable systems. A PD continuous online...

Robustness analysis of an adjoint optimal iterative learning controller with experimental verification (2008)

Ratcliffe, J D, Hatonen, J J, Lewin, P L, Rogers, E, Owens, D H

A new modification to the steepest-descent algorithm for discrete-time iterative learning control is developed for plant models with multiplicative uncertainty. A theoretical analysis of the...

The Effect of an Electric Field on Behaviour of Thermally Induced Bubble in Liquid Nitrogen (2008)

Wang, P, Swaffield, D J, Lewin, P L, Chen, G

The effect of a dc uniform electric field on the behaviour of bubbles in liquid nitrogen such as their growth, deformation and departure frequency has been experimentally investigated. The experiment...

A Model for Bubble Motion in Non-uniform Electric Fields (2008)

Lewin, P L, Wang, P, Swaffield, D J, Chen, G

fluids has found positive application for enhanced boiling heat transfer, for example in refrigerators. However the motion of bubbles in columns of dielectric fluid is also of interest where the...

A new approach to the study of surface discharge on the oil-pressboard interface (2008)

Mitchinson, P M, Lewin, P L, Chen, George, Jarman, P N

The materials used as the dielectric media of choice in large transformers continue to be a combination of pressboard and mineral oil. These materials offer a cost effective solution and are backed...

Studies on the Applicability of the Pockels Technique to Measure Surface Discharge in Liquid Dielectrics (2008)

Tran, T N, Lewin, P L, Swaffield, D J, Wilkinson, J S

This paper studies the feasibility of applying the electro-optical Pockels technique to measure surface discharge at a solid-liquid insulation interface. The principle of the method is based on the...

Thermal Bubble Motion in Liquid Nitrogen under Nonuniform Electric Fields (2008)

Wang, P, Swaffield, D J, Lewin, P L, Chen, G

This paper describes an experimental study into the influence of a non-uniform electric field on bubble motion and behavior in liquid nitrogen. The electric field effect on bubble motion as it rises...

Partial Discharge Characterization of Streamers in Liquid Nitrogen under Applied AC Voltages (2008)

Swaffield, D J, Lewin, P L, Chen, G, Swingler, S G

Streamer growth has been examined with the aim to further understand the issues related to using liquid nitrogen as a part of a dielectric system within power apparatus using high temperature...

Dynamic Measurement of Surface Discharge under Different Gaseous Environments and Pressures (2008)

Tran, T N, Lewin, P L, Wilkinson, J S, Swingler, S G, Coventry, P F

This paper is concerned with the application of the Pockels technique for measuring high voltage surface discharge under local conditions similar to those found in practical gas-insulated-switchgear....

An Investigation of Thermal Ratings for High Voltage Cable Joints through the use of 2D and 3D Finite Element Analysis (2008)

Pilgrim, J A, Swaffield, D J, Lewin, P L, Payne, D

The operation of power transmission systems requires accurate current ratings for each component within the system. With improvements in computational power, the application of modelling techniques...

Using optical couplers to monitor the condition of electricity infrastructure (2008)

Swingler, S G, Hao, L, Lewin, P L, Swaffield, D J

Increases in renewable and distributed generation will change the operational characteristics of our ageing power networks. To cope with these changes improved monitoring of the performance of...

Methods for rating directly buried high voltage cable circuits (2008)

Swaffield, D J, Lewin, P L, Sutton, S J

To manage a cable network effectively it is desirable to rate cable assets precisely. To investigate the conservatism of cable ratings provided by accepted modelling approaches several models have...

Methods for rating directly buried high voltage cable circuits (2008)

Swaffield, D J, Lewin, P L, Sutton, S J

To manage a cable network effectively it is desirable to rate cable assets precisely. To investigate the conservatism of cable ratings provided by accepted modelling approaches several models have...

Improving detection sensitivity for partial discharge monitoring of high voltage equipment (2008)

Hao, L, Lewin, P L, Swingler, S G

Partial discharge (PD) measurements are an important technique for assessing the health of power apparatus. Previous published research by the authors has shown that an electro-optic system can be...

Improving detection sensitivity for partial discharge monitoring of high voltage equipment (2008)

Hao, L, Lewin, P L, Swingler, S G

Partial discharge (PD) measurements are an important technique for assessing the health of power apparatus. Previous published research by the authors has shown that an electro-optic system can be...

Identification of Multiple Partial Discharge Sources (2008)

Hao, L, Lewin, P L, Swingler, S G

Partial discharge (PD) measurements are an important tool for assessing the health of power equipment. Different PD may have different effects on the insulation performance of power apparatus....

Phase-Resolved Measurement and Modelling of Electroluminescence Phenomenon in Polyethylene Subjected to High Electrical Stress (2008)

Mohd Ariffin, A, Lewin, P L

Electroluminescence (EL) has been widely used as a probe to study early electrical ageing in high voltage cable insulation systems since it can be associated with the energy dissipation of mobile and...

Identification of Multiple Partial Discharge Sources (2008)

Hao, L, Lewin, P L, Swingler, S G

Partial discharge (PD) measurements are an important tool for assessing the health of power equipment. Different PD may have different effects on the insulation performance of power apparatus....

Phase-Resolved Measurement and Modelling of Electroluminescence Phenomenon in Polyethylene Subjected to High Electrical Stress (2008)

Mohd Ariffin, A, Lewin, P L

Electroluminescence (EL) has been widely used as a probe to study early electrical ageing in high voltage cable insulation systems since it can be associated with the energy dissipation of mobile and...

ROBUST ILC DESIGN USING MÖBIUS TRANSFORMATIONS (2008)

C. T. Freeman, P. L. Lewin, E. Rogers

Abstract: In this paper a general ILC algorithm is examined and it is found that the filters involved can be selected to satisfy frequency-wise uncertainty limits on the plant model. The probability...

Zero Phase Filtering for Lightning Impulse Evaluation: A K-factor Filter for the Revision of IEC60060-1 and-2 (2008)

Lewin, P L, Tran, T N, Swaffield, D J, Hallstrom, J K

The next revision of the international standard for high voltage measurement techniques, IEC 60060-1, is planned to include a new method for evaluating the parameters associated with lightning...

Zero Phase Filtering for Lightning Impulse Evaluation: A K-factor Filter for the Revision of IEC60060-1 and-2 (2008)

Lewin, P L, Tran, T N, Swaffield, D J, Hallstrom, J K

The next revision of the international standard for high voltage measurement techniques, IEC 60060-1, is planned to include a new method for evaluating the parameters associated with lightning...

Iterative Learning Control For a Non-minimum Phase Plant Based on a Reference Shift Algorithm (2008)

Cai, Z, Freeman, C T, Lewin, P L, Rogers, E

In order to improve the tracking performance of a non-minimum phase plant, a new method called the reference shift algorithm has been developed to overcome the problem of output lag encountered when...

Iterative Learning Control For a Non-minimum Phase Plant Based on a Reference Shift Algorithm (2008)

Cai, Z, Freeman, C T, Lewin, P L, Rogers, E

In order to improve the tracking performance of a non-minimum phase plant, a new method called the reference shift algorithm has been developed to overcome the problem of output lag encountered when...

Shoulder and elbow muscle activity during fully supported trajectory tracking in neurologically intact older people (2008)

Hughes, A.M., Freeman, C.T., Burridge, J.H., Chappell, P.H., Lewin, P.L., Pickering, R.M., ...

An inability to perform tasks involving reaching is a common problem for stroke patients. Knowledge of normal muscle activation patterns during these tasks is essential to the identification of...

Lightning impulse waveshapes: defining the true origin and its impact on parameter evaluation (2007)

Swaffield, D.J., Lewin, P.L., Dao, N.L., Hallstrom, J.K.

High-voltage testing of equipment is conducted in accordance with IEC 60060-1 which defines the parameters of full lightning impulse waveshape and methods for generating and recording the test...

Repetitive control of synchronized operations for process applications (2007)

Ratcliffe, J D, Hatonen, J J, Lewin, P L, Rogers, E, Owens, D H

Repetitive control (RC) algorithms for a plant, which contain pairs of complex conjugate poles at low frequency, resulting in a resonant system, is the subject area of this paper where the...

Repetitive control of synchronized operations for process applications (2007)

Ratcliffe, J D, Hatonen, J J, Lewin, P L, Rogers, E, Owens, D H

Repetitive control (RC) algorithms for a plant, which contain pairs of complex conjugate poles at low frequency, resulting in a resonant system, is the subject area of this paper where the...

Repetitive control of synchronized operations for process applications (2007)

Ratcliffe, J D, Hatonen, J J, Lewin, P L, Rogers, E, Owens, D H

Repetitive control (RC) algorithms for a plant, which contain pairs of complex conjugate poles at low frequency, resulting in a resonant system, is the subject area of this paper where the...

Further results on the experimental evaluation of iterative learning control algorithms for non-minimum phase plants (2007)

Freeman, C T, Lewin, P L, Rogers, E

This paper builds on previous work in which simple structure ILC algorithms were experimentally evaluated on a non-minimum phase plant. The phase-lead update law, the most promising of those...

Further results on the experimental evaluation of iterative learning control algorithms for non-minimum phase plants (2007)

Freeman, C T, Lewin, P L, Rogers, E

This paper builds on previous work in which simple structure ILC algorithms were experimentally evaluated on a non-minimum phase plant. The phase-lead update law, the most promising of those...

Further results on the experimental evaluation of iterative learning control algorithms for non-minimum phase plants (2007)

Freeman, C T, Lewin, P L, Rogers, E

This paper builds on previous work in which simple structure ILC algorithms were experimentally evaluated on a non-minimum phase plant. The phase-lead update law, the most promising of those...

An Experimental Facility for the Application of Iterative Learning Control as an Intervention Aid to Stroke Rehabilitation (2007)

Freeman, C T, Hughes, A-M, Burridge, J H, Chappell, P H, Lewin, P L, Rogers, E

The concept of ‘learned disuse’ is thought to be a significant barrier to recovery of sensory-motor function following a stroke. Unimpaired individuals learn new skills though practice, with...

An Experimental Facility for the Application of Iterative Learning Control as an Intervention Aid to Stroke Rehabilitation (2007)

Freeman, C T, Hughes, A-M, Burridge, J H, Chappell, P H, Lewin, P L, Rogers, E

The concept of ‘learned disuse’ is thought to be a significant barrier to recovery of sensory-motor function following a stroke. Unimpaired individuals learn new skills though practice, with...

An Experimental Facility for the Application of Iterative Learning Control as an Intervention Aid to Stroke Rehabilitation (2007)

Freeman, C T, Hughes, A-M, Burridge, J H, Chappell, P H, Lewin, P L, Rogers, E

The concept of ‘learned disuse’ is thought to be a significant barrier to recovery of sensory-motor function following a stroke. Unimpaired individuals learn new skills though practice, with...

An Experimental Facility using Functional Electrical Stimulation for Stroke Rehabilitation of the Upper Limb (2007)

Freeman, C T, Hughes, A-M, Burridge, J, Chappell, P H, Lewin, P L, Rogers, E

A summary of the design and functionality of a robotic workstation that has been constructed for use by stroke patients in order to improve voluntary control of their impaired arm is first given in...

Simulation of Electroluminescence using a Bipolar Recombination Model (2007)

Lewin, P L, Dodd, S J, Mohd Ariffin, A

A dynamic bipolar charge recombination model originally developed to explain charge injection and electroluminescent (EL) behaviour of pin-plane polymeric resin samples under ac stress has been...

Application of Finite Element Analysis to externally forced water cooled cable circuit ratings (2007)

Swaffield, D J, Lewin, P L, Sutton, S J

In order to increase the available current carrying capacity of high voltage cables, utilities may employ forced water cooling within power transmission networks to remove the heat from cable groups....

Zero Phase Filtering for Lightning Impulse Evaluation: A K-factor Filter for the Revision of IEC60060-1 and-2 (2007)

Lewin, P L, Tran, T N, Swaffield, D J, Hallstrom, J K

The next revision of the international standard for high voltage measurement techniques, IEC 60060-1, is planned to include a new method for evaluating the parameters associated with lightning...

Partial Discharge Source Characterization within a HV Cable Joint (2007)

Hao, L, Lewin, P L, Dodd, S J

A parameter for partial discharge (PD) source location within a joint bay of a three phase cross-bonded high voltage cable circuit has been assessed. Locally placed sensors can detect PD pulses that...

An Experimental Facility using Functional Electrical Stimulation for Stroke Rehabilitation of the Upper Limb (2007)

Freeman, C T, Hughes, A-M, Burridge, J, Chappell, P H, Lewin, P L, Rogers, E

A summary of the design and functionality of a robotic workstation that has been constructed for use by stroke patients in order to improve voluntary control of their impaired arm is first given in...

Simulation of Electroluminescence using a Bipolar Recombination Model (2007)

Lewin, P L, Dodd, S J, Mohd Ariffin, A

A dynamic bipolar charge recombination model originally developed to explain charge injection and electroluminescent (EL) behaviour of pin-plane polymeric resin samples under ac stress has been...

Application of Finite Element Analysis to externally forced water cooled cable circuit ratings (2007)

Swaffield, D J, Lewin, P L, Sutton, S J

In order to increase the available current carrying capacity of high voltage cables, utilities may employ forced water cooling within power transmission networks to remove the heat from cable groups....

An Experimental Facility using Functional Electrical Stimulation for Stroke Rehabilitation of the Upper Limb (2007)

Freeman, C T, Hughes, A-M, Burridge, J, Chappell, P H, Lewin, P L, Rogers, E

A summary of the design and functionality of a robotic workstation that has been constructed for use by stroke patients in order to improve voluntary control of their impaired arm is first given in...

Simulation of Electroluminescence using a Bipolar Recombination Model (2007)

Lewin, P L, Dodd, S J, Mohd Ariffin, A

A dynamic bipolar charge recombination model originally developed to explain charge injection and electroluminescent (EL) behaviour of pin-plane polymeric resin samples under ac stress has been...

Application of Finite Element Analysis to externally forced water cooled cable circuit ratings (2007)

Swaffield, D J, Lewin, P L, Sutton, S J

In order to increase the available current carrying capacity of high voltage cables, utilities may employ forced water cooling within power transmission networks to remove the heat from cable groups....

Partial Discharge Source Characterization within a HV Cable Joint (2007)

Hao, L, Lewin, P L, Dodd, S J

A parameter for partial discharge (PD) source location within a joint bay of a three phase cross-bonded high voltage cable circuit has been assessed. Locally placed sensors can detect PD pulses that...

Classification of Partial Discharge Signals using Probabilistic Neural Network (2007)

Evagorou, D, Kyprianou, A, Lewin, P L, Stavrou, A, Efthymiou, V, Georghiou, G E

Partial Discharge (PD) classification in power cables and high voltage equipment is essential in evaluating the severity of the damage in the insulation. In this paper, the Probabilistic Neural...

Determining the Occurrence of Electroluminescence in Polymeric Materials with respect to the Applied Alternating Electrical Stress (2007)

Mohd Ariffin, A, Lewin, P L, Dodd, S J

The emission of low level of light known as the electroluminescence (EL) has been used extensively to study charge injection and recombination mechanisms at the metal-polymer interface. This...

Investigation of Transient Currents on Salt Contaminated Polymeric Insulator Surfaces (2007)

Swaffield, D J, Lewin, P L, Hilmi, N A, Pratt, H M O

To prevent potentially fatal electrocution when a construction crane accidentally touches a power line a load bearing electrical insulating link can be used. This is placed between the crane hook and...

Partial Discharge Source Characterization within a HV Cable Joint (2007)

Hao, L, Lewin, P L, Dodd, S J

A parameter for partial discharge (PD) source location within a joint bay of a three phase cross-bonded high voltage cable circuit has been assessed. Locally placed sensors can detect PD pulses that...

Classification of Partial Discharge Signals using Probabilistic Neural Network (2007)

Evagorou, D, Kyprianou, A, Lewin, P L, Stavrou, A, Efthymiou, V, Georghiou, G E

Partial Discharge (PD) classification in power cables and high voltage equipment is essential in evaluating the severity of the damage in the insulation. In this paper, the Probabilistic Neural...

Determining the Occurrence of Electroluminescence in Polymeric Materials with respect to the Applied Alternating Electrical Stress (2007)

Mohd Ariffin, A, Lewin, P L, Dodd, S J

The emission of low level of light known as the electroluminescence (EL) has been used extensively to study charge injection and recombination mechanisms at the metal-polymer interface. This...

Investigation of Transient Currents on Salt Contaminated Polymeric Insulator Surfaces (2007)

Swaffield, D J, Lewin, P L, Hilmi, N A, Pratt, H M O

To prevent potentially fatal electrocution when a construction crane accidentally touches a power line a load bearing electrical insulating link can be used. This is placed between the crane hook and...

Can Iterative Learning Control be used in the Re-education of Upper Limb Function, Mediated by Functional Electrical Stimulation (FES)? (2007)

Hughes, A.M., Freeman, C.T., Burridge, J.H., Chappell, P.H., Lewin, P.L., Rogers, E.

Introduction There is a body of clinical evidence to support the use of FES to improve motor control (De Kroon et al. 2002) and theoretical support from neurophysiology (Burridge & Ladouceur 2001)...

Can Iterative Learning Control be used in the Re-education of Upper Limb Function, Mediated by Functional Electrical Stimulation (FES)? (2007)

Hughes, A.M., Freeman, C.T., Burridge, J.H., Chappell, P.H., Lewin, P.L., Rogers, E.

Introduction There is a body of clinical evidence to support the use of FES to improve motor control (De Kroon et al. 2002) and theoretical support from neurophysiology (Burridge & Ladouceur 2001)...

An Investigation into Multi-Source Partial Discharge Discrimination within a Power Transformer Model (2007)

Hao, L, Lewin, P L

This paper investigates a new multi-PD-source discrimination method using machine learning technique, namely support vector machine (SVM). A bushing-tap-RFCT (Radio Frequency Current Transducer)...

Investigation on Electroluminescence Phenomenon in Insulating Polymers under the Influence of Different Gas Environments (2007)

Mohd Ariffin, A, Lewin, P L, Dodd, S J

Space charge plays a significant role in longterm electrical degradation of polymeric insulation in high voltage cables. Thus many researchers are interested to investigate further on the energy...

An Investigation into Multi-Source Partial Discharge Discrimination within a Power Transformer Model (2007)

Hao, L, Lewin, P L

This paper investigates a new multi-PD-source discrimination method using machine learning technique, namely support vector machine (SVM). A bushing-tap-RFCT (Radio Frequency Current Transducer)...

Investigation on Electroluminescence Phenomenon in Insulating Polymers under the Influence of Different Gas Environments (2007)

Mohd Ariffin, A, Lewin, P L, Dodd, S J

Space charge plays a significant role in longterm electrical degradation of polymeric insulation in high voltage cables. Thus many researchers are interested to investigate further on the energy...

Lightning impulse waveshapes: Defining the true origin and its impact on parameter evaluation. (2007)

Swaffield, D J, Lewin, P L, Dao, N L, Hallstrom, J K

High-voltage testing of equipment is conducted in accordance with IEC 60060-1 which defines the parameters of full lighning impulse wave-shapes and methods for generating and recording the test...

Thermal Bubble Motion in Liquid Nitrogen under Non-Uniform Electric Fields (2007)

Wang, P, Swaffield, D J, Lewin, P L, Chen, G

This paper describes an experimental study of the influence of a non-uniform electric field on bubble motion and behaviour in liquid nitrogen. The electric field effect on the bubble motion as it...

Lightning impulse waveshapes: Defining the true origin and its impact on parameter evaluation. (2007)

Swaffield, D J, Lewin, P L, Dao, N L, Hallstrom, J K

High-voltage testing of equipment is conducted in accordance with IEC 60060-1 which defines the parameters of full lighning impulse wave-shapes and methods for generating and recording the test...

Thermal Bubble Motion in Liquid Nitrogen under Non-Uniform Electric Fields (2007)

Wang, P, Swaffield, D J, Lewin, P L, Chen, G

This paper describes an experimental study of the influence of a non-uniform electric field on bubble motion and behaviour in liquid nitrogen. The electric field effect on the bubble motion as it...

Condition Monitoring of Power Cables (2007)

Lewin, P L, Hao, L, Swaffield, D J, Swingler, S G

A National Grid funded research project at Southampton has investigated possible methodologies for data acquisition, transmission and processing that will facilitate on-line continuous monitoring of...

Condition Monitoring of Power Cables (2007)

Lewin, P L, Hao, L, Swaffield, D J, Swingler, S G

A National Grid funded research project at Southampton has investigated possible methodologies for data acquisition, transmission and processing that will facilitate on-line continuous monitoring of...

The Influence of Absorbed Gases on Electroluminescence Phenomenon in Polymeric Materials Subjected to High Electrical Stress (2007)

Mohd Ariffin, A, Lewin, P L, Dodd, S J

Whenever a polymeric material is subjected to an electrical stress, imperfections such as protrusions, contaminants and microvoids, will all act as points where the field is enhanced, causing the...

Creep Stress Failure in High Voltage Transformer Interwinding Insulation (2007)

Mitchinson, P M, Lewin, P L, Chen, G, Jarman, P N

Three phase transformers have an insulation system which is a complex three dimensional structure of paper and pressboard surrounding the conductors immersed in a large volume of mineral oil. In core...

The Influence of Absorbed Gases on Electroluminescence Phenomenon in Polymeric Materials Subjected to High Electrical Stress (2007)

Mohd Ariffin, A, Lewin, P L, Dodd, S J

Whenever a polymeric material is subjected to an electrical stress, imperfections such as protrusions, contaminants and microvoids, will all act as points where the field is enhanced, causing the...

Creep Stress Failure in High Voltage Transformer Interwinding Insulation (2007)

Mitchinson, P M, Lewin, P L, Chen, G, Jarman, P N

Three phase transformers have an insulation system which is a complex three dimensional structure of paper and pressboard surrounding the conductors immersed in a large volume of mineral oil. In core...

Thermal Bubble Behaviour in Liquid Nitrogen between Inclined Plane Electrodes (2007)

Wang, P, Swaffield, D J, Lewin, P L, Chen, G

This paper describes an experimental study of the behaviour of thermally nucleated bubbles in liquid nitrogen between inclined plane-plane electrodes with an angle of 21°. Observation of the bubble...

Thermal Bubble Behaviour in Liquid Nitrogen between Inclined Plane Electrodes (2007)

Wang, P, Swaffield, D J, Lewin, P L, Chen, G

This paper describes an experimental study of the behaviour of thermally nucleated bubbles in liquid nitrogen between inclined plane-plane electrodes with an angle of 21°. Observation of the bubble...

Norm-Optimal Iterative Learning Control Applied to Gantry Robots for Automation Applications (2006)

Ratcliffe, J D, Lewin, P L, Rogers, E, Hatonen, J J, Owens, D H

This paper is concerned with the practical implementation of the norm-optimal iterative learning control (NOILC) algorithm. Here, the complexity of this algorithm is first considered with respect to...

Norm-Optimal Iterative Learning Control Applied to Gantry Robots for Automation Applications (2006)

Ratcliffe, J D, Lewin, P L, Rogers, E, Hatonen, J J, Owens, D H

This paper is concerned with the practical implementation of the norm-optimal iterative learning control (NOILC) algorithm. Here, the complexity of this algorithm is first considered with respect to...

Norm-Optimal Iterative Learning Control Applied to Gantry Robots for Automation Applications (2006)

Ratcliffe, J D, Lewin, P L, Rogers, E, Hatonen, J J, Owens, D H

This paper is concerned with the practical implementation of the norm-optimal iterative learning control (NOILC) algorithm. Here, the complexity of this algorithm is first considered with respect to...

Wavelet packet denoising for online partial discharge detection in cables and its application to experimental field results (2006)

Kyprianou, A, Lewin, P L, Efthimiou, V, Stavrou, A, Georghiou, G E

Partial discharge measurements taken online are severely corrupted by noise due to external disturbances. In this paper a powerful noise reduction technique, based on a wavelet packet denoising...

Wavelet packet denoising for online partial discharge detection in cables and its application to experimental field results (2006)

Kyprianou, A, Lewin, P L, Efthimiou, V, Stavrou, A, Georghiou, G E

Partial discharge measurements taken online are severely corrupted by noise due to external disturbances. In this paper a powerful noise reduction technique, based on a wavelet packet denoising...

Wavelet packet denoising for online partial discharge detection in cables and its application to experimental field results (2006)

Kyprianou, A, Lewin, P L, Efthimiou, V, Stavrou, A, Georghiou, G E

Partial discharge measurements taken online are severely corrupted by noise due to external disturbances. In this paper a powerful noise reduction technique, based on a wavelet packet denoising...

Application of electro-optic modulation technique for PD monitoring of power transformers (2006)

Hao, L., Lewin, P.L., Tian, Y., Wilkinson, J.S., Swingler, S.G., Sutton, S.J.

Partial discharge (PD) detection is an important technique for assessing the health of high voltage power transformers. A partial discharge signal within an oil-filled power transformer may reach a...

Phase Resolved Electroluminescence Measurements in Thin Films of Low Density Polyethylene Using a Charge Coupled Device Camera (2006)

Dodd, S J, Lewin, P L, Wong, K I

Electroluminescence (EL) produced by a commercially available additive free low density polyethylene film has been investigated under a 50Hz ac electrical stress. The spatial distribution, spectral...

Phase Resolved Electroluminescence Measurements in Thin Films of Low Density Polyethylene Using a Charge Coupled Device Camera (2006)

Dodd, S J, Lewin, P L, Wong, K I

Electroluminescence (EL) produced by a commercially available additive free low density polyethylene film has been investigated under a 50Hz ac electrical stress. The spatial distribution, spectral...

Phase Resolved Electroluminescence Measurements in Thin Films of Low Density Polyethylene Using a Charge Coupled Device Camera (2006)

Dodd, S J, Lewin, P L, Wong, K I

Electroluminescence (EL) produced by a commercially available additive free low density polyethylene film has been investigated under a 50Hz ac electrical stress. The spatial distribution, spectral...

P-type iterative learning control for systems that contain resonance (2005)

Ratcliffe, J D, Hatonen, J J, Lewin, P L, Rogers, E, Harte, T J, Owens, D H

The effect of iterative learning control (ILC) on a plant containing resonance has been experimentally investigated using an industrial gantry robot. The plant is controlled by a PID controller and a...

An improved optically based PD detection system for continuous on-line monitoring of HV cables (2005)

Tian, Y, Lewin, P L, Wilkinson, J S, Shroeder, G, Sutton, S J, Swingler, S G

An optically-based remote sensing technique using a laser source, polarization scrambler, standard single mode fibres, fibre polarizer, electro-optic (EO) modulator and optical receiver, for...

P-type iterative learning control for systems that contain resonance (2005)

Ratcliffe, J D, Hatonen, J J, Lewin, P L, Rogers, E, Harte, T J, Owens, D H

The effect of iterative learning control (ILC) on a plant containing resonance has been experimentally investigated using an industrial gantry robot. The plant is controlled by a PID controller and a...

An improved optically based PD detection system for continuous on-line monitoring of HV cables (2005)

Tian, Y, Lewin, P L, Wilkinson, J S, Shroeder, G, Sutton, S J, Swingler, S G

An optically-based remote sensing technique using a laser source, polarization scrambler, standard single mode fibres, fibre polarizer, electro-optic (EO) modulator and optical receiver, for...

P-type iterative learning control for systems that contain resonance (2005)

Ratcliffe, J D, Hatonen, J J, Lewin, P L, Rogers, E, Harte, T J, Owens, D H

The effect of iterative learning control (ILC) on a plant containing resonance has been experimentally investigated using an industrial gantry robot. The plant is controlled by a PID controller and a...

An improved optically based PD detection system for continuous on-line monitoring of HV cables (2005)

Tian, Y, Lewin, P L, Wilkinson, J S, Shroeder, G, Sutton, S J, Swingler, S G

An optically-based remote sensing technique using a laser source, polarization scrambler, standard single mode fibres, fibre polarizer, electro-optic (EO) modulator and optical receiver, for...

Chromatic classification of RF signals produced by electrical discharges in HV transformers (2005)

Zhang, J, Jones, G R, Spencer, J W, Jarman, P, Kemp, I J, Wang, Z, ...

The results of investigations into the use of chromatic processing of radio frequency signals emitted from transformers known to be suffering from partial discharging are described. The work formed...

Chromatic classification of RF signals produced by electrical discharges in HV transformers (2005)

Zhang, J, Jones, G R, Spencer, J W, Jarman, P, Kemp, I J, Wang, Z, ...

The results of investigations into the use of chromatic processing of radio frequency signals emitted from transformers known to be suffering from partial discharging are described. The work formed...

Chromatic classification of RF signals produced by electrical discharges in HV transformers (2005)

Zhang, J, Jones, G R, Spencer, J W, Jarman, P, Kemp, I J, Wang, Z, ...

The results of investigations into the use of chromatic processing of radio frequency signals emitted from transformers known to be suffering from partial discharging are described. The work formed...

X-ray image processing for high voltage cable inspection (2005)

Robinson, A P, Lewin, P L, Swingler, S G, Sutton, S J

High voltage polymeric cables can be insulated using an automated extrusion process to a predefined standard up to a maximum continuous length. For longer cables, lengths are joined together...

X-ray image processing for high voltage cable inspection (2005)

Robinson, A P, Lewin, P L, Swingler, S G, Sutton, S J

High voltage polymeric cables can be insulated using an automated extrusion process to a predefined standard up to a maximum continuous length. For longer cables, lengths are joined together...

X-ray image processing for high voltage cable inspection (2005)

Robinson, A P, Lewin, P L, Swingler, S G, Sutton, S J

High voltage polymeric cables can be insulated using an automated extrusion process to a predefined standard up to a maximum continuous length. For longer cables, lengths are joined together...

Calibration of Capacitive Couplers for Online PD Detection in HV Cables (2005)

Wang, P, Lewin, P L, Sutton, S J

On-line partial discharge (PD) detection for high voltage cable systems is important as it ensures that possible faults can be detected and remedied before catastrophic failure occurs. Of growing...

Calibration of Capacitive Couplers for Online PD Detection in HV Cables (2005)

Wang, P, Lewin, P L, Sutton, S J

On-line partial discharge (PD) detection for high voltage cable systems is important as it ensures that possible faults can be detected and remedied before catastrophic failure occurs. Of growing...

Calibration of Capacitive Couplers for Online PD Detection in HV Cables (2005)

Wang, P, Lewin, P L, Sutton, S J

On-line partial discharge (PD) detection for high voltage cable systems is important as it ensures that possible faults can be detected and remedied before catastrophic failure occurs. Of growing...

Improvement on Measurement Sensitivity of the Optical Remote Sensing Based PD Continuous On-line Monitoring System for HV Cable Joints (2005)

Tian, Y, Lewin, P L, Wilkinson, J S, Sutton, S J, Swingler, S G

This paper investigates the improvement on measurement sensitivity of the electro-optic modulator based PD continuous online monitoring technique, which has been developed by the authors. The...

Improvement on Measurement Sensitivity of the Optical Remote Sensing Based PD Continuous On-line Monitoring System for HV Cable Joints (2005)

Tian, Y, Lewin, P L, Wilkinson, J S, Sutton, S J, Swingler, S G

This paper investigates the improvement on measurement sensitivity of the electro-optic modulator based PD continuous online monitoring technique, which has been developed by the authors. The...

An improved optically based PD detection system for continuous on-line monitoring of HV cables (2005)

Tian, Y., Lewin, P.L., Wilkinson, J.S., Schroeder, G., Sutton, S.J., Swingler, S.G.

An optically-based remote sensing technique using a laser source, polarization scrambler, standard single mode fibers, fiber polarizer, electro-optic (EO) modulator and optical receiver, for...

Partial discharge characterisation in liquid nitrogen composite systems (2005)

Swaffield, D.J., Lewin, P.L., Tian, Y., Chen, G., Swingler, S.G.

Interest in superconductors for use in the transmission and distribution of power has grown since the advent of high temperature superconductors (HTS). The benefits of reduced ohmic losses leading to...

Improvement on Measurement Sensitivity of the Optical Remote Sensing Based PD Continuous On-line Monitoring System for HV Cable Joints (2005)

Tian, Y, Lewin, P L, Wilkinson, J S, Sutton, S J, Swingler, S G

This paper investigates the improvement on measurement sensitivity of the electro-optic modulator based PD continuous online monitoring technique, which has been developed by the authors. The...

Improvement on measurement sensitivity of the optical remote sensing based PD continuous on-line monitoring system for HV cable joints (2005)

Tian, Y., Lewin, P.L., Wilkinson, J.S., Sutton, S.J., Swingler, S.G.

This paper investigates the improvement on measurement sensitivity of the electro-optic modulator based PD continuous online monitoring technique, which has been developed by the authors. The...

Chromatic classification of RF signals produced by electrical discharges in HV transformers (2005)

Zhang, J., Jones, G. R., Spencer, J. W., Jarman, P., Kemp, I. J., Wang, Z., ...

The results of investigations into the use of chromatic processing of radio frequency signals emitted from transformers known to be suffering from partial discharging are described. The work formed...

Variable Pressure and Temperature Liquid Nitrogen Cryostat for Optical Measurements with Applied Electric Fields (2004)

Swaffield, D J, Lewin, P L, Chen, G, Swingler, S G

A cryostat with a high-voltage bushing, optical observation ports, variable controlled temperature and pressure has been designed to further the study of liquid nitrogen as a dielectric medium. The...

Variable Pressure and Temperature Liquid Nitrogen Cryostat for Optical Measurements with Applied Electric Fields (2004)

Swaffield, D J, Lewin, P L, Chen, G, Swingler, S G

A cryostat with a high-voltage bushing, optical observation ports, variable controlled temperature and pressure has been designed to further the study of liquid nitrogen as a dielectric medium. The...

Variable Pressure and Temperature Liquid Nitrogen Cryostat for Optical Measurements with Applied Electric Fields (2004)

Swaffield, D J, Lewin, P L, Chen, G, Swingler, S G

A cryostat with a high-voltage bushing, optical observation ports, variable controlled temperature and pressure has been designed to further the study of liquid nitrogen as a dielectric medium. The...

Partial Discharge On-line Monitoring for HV Cable Systems Using Electrooptic Modulators (2004)

Tian, Y, Lewin, P L, Pommerenke, D, Wilkinson, J S, Sutton, S J

A technique for the remote inspection and monitoring of partial discharge (PD) activity using an optical network is described. The network uses a LiNbO3 modulator to modulate the intensity of the...

Partial Discharge On-line Monitoring for HV Cable Systems Using Electrooptic Modulators (2004)

Tian, Y, Lewin, P L, Pommerenke, D, Wilkinson, J S, Sutton, S J

A technique for the remote inspection and monitoring of partial discharge (PD) activity using an optical network is described. The network uses a LiNbO3 modulator to modulate the intensity of the...

Partial Discharge On-line Monitoring for HV Cable Systems Using Electrooptic Modulators (2004)

Tian, Y, Lewin, P L, Pommerenke, D, Wilkinson, J S, Sutton, S J

A technique for the remote inspection and monitoring of partial discharge (PD) activity using an optical network is described. The network uses a LiNbO3 modulator to modulate the intensity of the...

Optically-based partial discharge continuous monitoring system for HV cable joints (2004)

Tian, Y., Lewin, P.L., Wilkinson, J.S., Sutton, S.J., Swingler, S.G.

This paper describes the further development of a novel partial discharge continuous monitoring technique. The measurement mechanism applies capacitive coupler measured partial discharge signals...

Iterative Learning Control - 2D Control Systems From Theory to Application (2004)

Al-Towaim, T, Barton, A D, Lewin, P L, Rogers, E, Owens, D H

It has long been recognised that iterative learning control is a 2D system, i.e. information propagation occurs in two independent directions. In this paper, the application of so-called norm optimal...

Iterative Learning Control - 2D Control Systems From Theory to Application (2004)

Al-Towaim, T, Barton, A D, Lewin, P L, Rogers, E, Owens, D H

It has long been recognised that iterative learning control is a 2D system, i.e. information propagation occurs in two independent directions. In this paper, the application of so-called norm optimal...

Iterative Learning Control - 2D Control Systems From Theory to Application (2004)

Al-Towaim, T, Barton, A D, Lewin, P L, Rogers, E, Owens, D H

It has long been recognised that iterative learning control is a 2D system, i.e. information propagation occurs in two independent directions. In this paper, the application of so-called norm optimal...

Partial discharge on-line monitoring for HV cable systems using electro-optic modulators (2004)

Tian, Y., Lewin, P.L., Pommerenke, D., Wilkinson, J.S., Sutton, S.J.

A technique for the remote inspection and monitoring of partial discharge (PD) activity using an optical network is described. The network uses a LiNbO3 modulator to modulate the intensity of the...

Continuous online monitoring of partial discharges in high voltage cables (2004)

Tian, Y., Lewin, P.L., Wilkinson, J.S., Sutton, S.J., Swingler, S.G.

This paper reviews data acquisition, transmission and processing methodologies for continuous online monitoring of partial discharges in power cable systems. A PD continuous online monitoring system...

Continuous online monitoring of partial discharges in high voltage cables (2004)

Tian, Y., Lewin, P.L., Wilkinson, J.S., Sutton, S.J., Swingler, S.G.

This paper reviews data acquisition, transmission and processing methodologies for continuous online monitoring of partial discharges in power cable systems. A PD continuous online monitoring system...

Iterative Learning Control (2003)

Lewin, P L

Iterative Learning Control (ILC) was first proposed in 1984 by Arimoto, Miyazaki and Kawamura (1) and allows process tools such as robot arms and production machinery to repeat actions or synchronise...

Partial Discharge Detection in Cables Using VHF Capacitive Couplers (2003)

Tian, Y, Lewin, P L, Davies, A E, Sutton, S J, Swingler, S G

In order to detect and locate partial discharge (PD) activity within HV cables and in particular cable joints, the feasibility of using a very high frequency (VHF) capacitive coupler technique has...

Iterative Learning Control (2003)

Lewin, P L

Iterative Learning Control (ILC) was first proposed in 1984 by Arimoto, Miyazaki and Kawamura (1) and allows process tools such as robot arms and production machinery to repeat actions or synchronise...

Partial Discharge Detection in Cables Using VHF Capacitive Couplers (2003)

Tian, Y, Lewin, P L, Davies, A E, Sutton, S J, Swingler, S G

In order to detect and locate partial discharge (PD) activity within HV cables and in particular cable joints, the feasibility of using a very high frequency (VHF) capacitive coupler technique has...

Iterative Learning Control (2003)

Lewin, P L

Iterative Learning Control (ILC) was first proposed in 1984 by Arimoto, Miyazaki and Kawamura (1) and allows process tools such as robot arms and production machinery to repeat actions or synchronise...

Partial Discharge Detection in Cables Using VHF Capacitive Couplers (2003)

Tian, Y, Lewin, P L, Davies, A E, Sutton, S J, Swingler, S G

In order to detect and locate partial discharge (PD) activity within HV cables and in particular cable joints, the feasibility of using a very high frequency (VHF) capacitive coupler technique has...

Surface Discharge Measurements of Polymeric Materials (2003)

Sam, Y L, Lewin, P L, Davies, A E, Wilkinson, J S, Sutton, S J, Swingler, S G

The measurement of surface charge is an important parameter for evaluating the electrical performance of high voltage insulation materials. The method proposed allows on line measurement of charge...

Surface Discharge Measurements of Polymeric Materials (2003)

Sam, Y L, Lewin, P L, Davies, A E, Wilkinson, J S, Sutton, S J, Swingler, S G

The measurement of surface charge is an important parameter for evaluating the electrical performance of high voltage insulation materials. The method proposed allows on line measurement of charge...

Surface discharge measurements of polymeric materials (2003)

Sam, Y.L., Lewin, P.L., Davies, A.E., Wilkinson, J.S., Sutton, S.J., Swingler, S.G.

The measurement of surface charge is an important parameter for evaluating the electrical performance of high voltage insulation materials. The method proposed allows on line mwurement of charge and...

Surface Discharge Measurements of Polymeric Materials (2003)

Sam, Y L, Lewin, P L, Davies, A E, Wilkinson, J S, Sutton, S J, Swingler, S G

The measurement of surface charge is an important parameter for evaluating the electrical performance of high voltage insulation materials. The method proposed allows on line measurement of charge...

Comparison of On-line Partial Discharge Detection Methods for HV Cable Joints (2002)

Tian, Y, Lewin, P L, Davies, A E, Swingler, S G, Sutton, S J, Hathaway, G M

The capacitive coupler, acoustic emission (AE) sensor and radio frequency current transducer (RFCT) have been used to detect partial discharge (PD) activity within a 132kV prefabricated cable joint...

Comparison of On-line Partial Discharge Detection Methods for HV Cable Joints (2002)

Tian, Y, Lewin, P L, Davies, A E, Swingler, S G, Sutton, S J, Hathaway, G M

The capacitive coupler, acoustic emission (AE) sensor and radio frequency current transducer (RFCT) have been used to detect partial discharge (PD) activity within a 132kV prefabricated cable joint...

Comparison of On-line Partial Discharge Detection Methods for HV Cable Joints (2002)

Tian, Y, Lewin, P L, Davies, A E, Swingler, S G, Sutton, S J, Hathaway, G M

The capacitive coupler, acoustic emission (AE) sensor and radio frequency current transducer (RFCT) have been used to detect partial discharge (PD) activity within a 132kV prefabricated cable joint...

The influence of local environmental conditions on surface discharge behaviour (2002)

Sam, Y.L., Lewin, P.L., Davies, A.E., Wilkinson, J.S., Sutton, S.J., Swingler, S.G.

The measurement of surface charge is important in determining the electrical performance of high voltage insulation materials. This paper is concerned with surface charge measurements utilising...

Dynamic AC surface discharge characteristics of PMMA and LDPE (2001)

Sam, Y.L., Lewin, P.L., Davies, A.E., Wilkinson, J.S., Sutton, S.J., Swingler, S.G.

Polymeric materials such as Low Density Polyethylene (LDPE) and Polymethylmethacrylate (PMMA) have properties that are ideal for use as electrical insulating materials within a wide range of...

Experimental Comparison of the Performance of Different Chain Conveyor Controllers (2000)

Barton, A D, Lewin, P L

Current control methods for chain conveyor systems in manufacturing consist almost exclusively of proportional, integral and differential (PID) control implemented using programmable logic...

Experimental Comparison of the Performance of Different Chain Conveyor Controllers (2000)

Barton, A D, Lewin, P L

Current control methods for chain conveyor systems in manufacturing consist almost exclusively of proportional, integral and differential (PID) control implemented using programmable logic...

Experimental Comparison of the Performance of Different Chain Conveyor Controllers (2000)

Barton, A D, Lewin, P L

Current control methods for chain conveyor systems in manufacturing consist almost exclusively of proportional, integral and differential (PID) control implemented using programmable logic...

Dynamic measurement of surface charge (2000)

Sam, Y.L., Lewin, P.L., Davies, A.E., Wilkinson, J.S., Sutton, S.J., Swingler, S.G.

This paper describes the development of a system capable of monitoring the dynamic movement of surface charge on insulating materials. High electrical stress can be generated at the edges of an...

Practical Implementation of a Real-time Iterative Learning Position Controller (2000)

Barton, A D, Lewin, P L, Brown, D J

Current control methods for chain conveyor systems in manufacturing consist almost exclusively of proportional plus integral plus differential (PID) control implemented using a programmable logic...

Practical Implementation of a Real-time Iterative Learning Position Controller (2000)

Barton, A D, Lewin, P L, Brown, D J

Current control methods for chain conveyor systems in manufacturing consist almost exclusively of proportional plus integral plus differential (PID) control implemented using a programmable logic...

Practical Implementation of a Real-time Iterative Learning Position Controller (2000)

Barton, A D, Lewin, P L, Brown, D J

Current control methods for chain conveyor systems in manufacturing consist almost exclusively of proportional plus integral plus differential (PID) control implemented using a programmable logic...

Method to Determine the Activation Energy of a Polymeric Material from Thermally Stimulated Discharge Current Measurements (2000)

Wang, X, Lewin, P L, Davies, A E, Sutton, S J

An alternative method of estimating the average trap depth from the thermally stimulated discharge current measurement of a polymeric material is detailed. The method uses least square numerical...

Method to Determine the Activation Energy of a Polymeric Material from Thermally Stimulated Discharge Current Measurements (2000)

Wang, X, Lewin, P L, Davies, A E, Sutton, S J

An alternative method of estimating the average trap depth from the thermally stimulated discharge current measurement of a polymeric material is detailed. The method uses least square numerical...

Method to Determine the Activation Energy of a Polymeric Material from Thermally Stimulated Discharge Current Measurements (2000)

Wang, X, Lewin, P L, Davies, A E, Sutton, S J

An alternative method of estimating the average trap depth from the thermally stimulated discharge current measurement of a polymeric material is detailed. The method uses least square numerical...

Method for rating power cables buried in surface troughs (1999)

Lewin, P.L., Theed, J.E., Davies, A.E., Larsen, S.T.

An alternative method is detailed by which the ambient temperature parameter as applied to the calculation of ratings of cables buried in surface trough installations can be determined. Improvement...

Method for rating power cables buried in surface troughs (1999)

Lewin, P.L., Theed, J.E., Davies, A.E., Larsen, S.T.

An alternative method is detailed by which the ambient temperature parameter as applied to the calculation of ratings of cables buried in surface trough installations can be determined. Improvement...

Method for rating power cables buried in surface troughs (1999)

Lewin, P.L., Theed, J.E., Davies, A.E., Larsen, S.T.

An alternative method is detailed by which the ambient temperature parameter as applied to the calculation of ratings of cables buried in surface trough installations can be determined. Improvement...

Surge attenuation in cable systems (1996)

Davies, A.E., Lewin, P.L., Tong, Y.K.

Details an equivalent circuit model used to simulate voltage surge attenuation within concentric cylindrical transmission systems. The model is frequency independent and accommodates the linear...

Surge attenuation in cable systems (1996)

Davies, A.E., Lewin, P.L., Tong, Y.K.

Details an equivalent circuit model used to simulate voltage surge attenuation within concentric cylindrical transmission systems. The model is frequency independent and accommodates the linear...

Surge attenuation in cable systems (1996)

Davies, A.E., Lewin, P.L., Tong, Y.K.

Details an equivalent circuit model used to simulate voltage surge attenuation within concentric cylindrical transmission systems. The model is frequency independent and accommodates the linear...

A Frequency Independent Circuit Model of a Conductor under Surge Conditions (1995)

Davies, A E, Tong, Y K, Lewin, P L, German, D M

This paper presents a circuit-based model of a current carrying conductor that can provide instantaneous ohmic losses under surge conditions. The model is frequency independent and can be used to...

Frequency-independent circuit model of earth return effects in transmission systems (1995)

Davies, A E, Tong, Y K, Lewin, P L, German, D M

The paper presents an alternative method of calculating the impedance correction terms of an overhead transmission line by taking into account the effect of the earth return. A circuit-based model is...

A Frequency Independent Circuit Model of a Conductor under Surge Conditions (1995)

Davies, A E, Tong, Y K, Lewin, P L, German, D M

This paper presents a circuit-based model of a current carrying conductor that can provide instantaneous ohmic losses under surge conditions. The model is frequency independent and can be used to...

Frequency-independent circuit model of earth return effects in transmission systems (1995)

Davies, A E, Tong, Y K, Lewin, P L, German, D M

The paper presents an alternative method of calculating the impedance correction terms of an overhead transmission line by taking into account the effect of the earth return. A circuit-based model is...

A Frequency Independent Circuit Model of a Conductor under Surge Conditions (1995)

Davies, A E, Tong, Y K, Lewin, P L, German, D M

This paper presents a circuit-based model of a current carrying conductor that can provide instantaneous ohmic losses under surge conditions. The model is frequency independent and can be used to...

Frequency-independent circuit model of earth return effects in transmission systems (1995)

Davies, A E, Tong, Y K, Lewin, P L, German, D M

The paper presents an alternative method of calculating the impedance correction terms of an overhead transmission line by taking into account the effect of the earth return. A circuit-based model is...