Power System Electronics
The Power System Electronics work stream has contributed to two themes; Multi-terminal HVDC and Active Distribution.
Multi-terminal HVDC
The topic of multi-terminal HVDC continues to rise in importance as a consideration within both the connection of very large off-shore wind farms and a EU-wide super-grid advance. To date, HVDC deployment has been limited to point-to-point connections. This work is focused on the technologies to realise interconnection through multi-terminal DC networks.
Three PhD students have now completed two years of research and recently appointed research assistants have initiated additional experimental facilities. Deliverables include:
Verification of power-flow control and DC voltage regulation: A control system of a multi-terminal HVDC scheme for offshore wind power transmission has been designed and tested through simulation. The operation of multi-terminal HVDC has been studied under normal operation and fault conditions. A three terminal HVDC test rig has been commissioned and is being used to test multi-terminal HVDC operation.
Investigation of damping of sub-synchronous resonance through HVDC links.
Characterisation of response of converters to DC- and AC-side faults: A component-level simulation of a modular-multi-level AC/DC power converter has been compiled and control schemes for capacitor voltages and line currents during faults were designed and tested.
Active Distribution
Deliverables have included:
Assessment of Soft-Open-Points against other methods of distributed generation (DG) management: Placing back-to-back power converters across network open points to form soft-open-points (SOPs) was identified as a means to increase meshing and provide more DG connection capacity without contributing to fault current rise. Results have now been generated for 12 example networks to quantify the increased DG capacity versus traditional and other active means of capacity expansion. A laboratory demonstrator is now being assembled.
Endurance test data for ?wear-less? tap-changer: The ?wear-less? tap-changer design (patented last year) has now been tested for more than 20 million operations at realistic current and inter-tap voltage. Photographic evidence of contact condition has been obtained for zero-current opening in comparison with both ?hard? opening and use of a conventional passive diverter.
Dr Stephen J Finney
Department of Electronic & Electrical Engineering
Royal College Building
204 George Street
Glasgow, G1 1XW,UK
Tel: +44 (0) 141 548 2516
Email: s.finney@eee.strath.ac.uk