Power Applications

Global warming, pollution and energy shortages are probably the most serious challenges now facing mankind.  There has been an enormous upsurge of activity in developing renewable energy sources; less well-publicised are the problems of power quality (harmonics), system stability, reliability, and energy storage associated with renewable energy generation.  Embedded power generators may cause voltage variations to exceed their set limits, produce voltage unbalance and also result in unwanted harmonic distortion when integrated into the network through electronic power converters.

The power group has projects addressing all stages of the energy cycle, from generation through to transmission, storage and ultimately usage.  Power electronic converters are an enabling technology for all energy conversion processes.  We continue to research new converter topologies, their fundamental properties as well as their applications, such as active harmonic filtering and power factor control in transmission and distribution systems.  Hybrid and unified power conditioners combining with advanced signal processing techniques such as the recursive wavelet method are developed to track and cancel harmonic disturbances and reduce flickers from micro-generators. Novel forms such as the Cuk converter and floating capacitor multilevel inverter are being investigated.  New results have recently been obtained on transient responses of the Cuk converter, and various forms of modulation techniques in the multilevel inverter; this we have recently applied to control of neutral conductor currents in unbalanced three-phase four-wire power distribution systems.

Work continues on investigating the optimal structure for integrating converters with small renewable generators and intelligent control schemes for high efficiency solar photovoltaic generation systems.  We have recently developed a distributed maximum power tracking technique for PV arrays that are partially shaded by obstructions.  A solar power laboratory has been established for testing different types of PV devices under controlled light conditions, for developing control strategies, and for teaching purposes.  Recent work on energy storage included developing neural network models and using particle swarm optimisation methods for lead acid storage batteries and fuel cells.  We have close links with power companies such as AREVA and SRD Drives in UK.

New model-based techniques for maximum power generation in doubly fed induction generators for wind power are being developed.  We also investigate signal-processing techniques for fault detection and system reconfiguration of wind powered induction generators.  Switched reluctance machines for wave power are being investigated.

The research on Switched Reluctance Drives has been an ongoing activity in the School for an extensive period and has included seminal work which has drawn a worldwide interest and led to a number of developments of both the generic and application oriented nature.

Current Projects

Academic staff
Dr J Corda
Dr L Zhang