Plenary Talks

 Session  Plenary Session
 Date/Time  Wednesday, 10 June 2015/09:30 – 12:30 hrs
 Venue  Stateroom @ Level 2

[330] Gallium Nitride Power Electronic Devices and Circuits: A Review

Graham Town

Gallium-nitride is an emerging power semiconductor technology with considerable promise for applications requiring compact and efficient power conversion at competitive cost. In this paper, gallium-nitride power electronic devices, circuits, and applications are reviewed and compared in terms of device specifications, circuit topologies, and cost.


[67] Analysis and Simulation of the Proactive Hybrid Circuit Breaker

Oliver Cwikowski, Bin Chang, Mike Barnes and Roger Shuttleworth
United Kingdom

High Voltage Direct Current (HVDC) short circuit protection is a fundamental requirement for any HVDC transmission system. Presently, all point-to-point links are protected using circuit breakers on the AC side of the converters. In order to enable HVDC grids, a more advanced protection system must be developed. HVDC circuit breakers are one solution for the protection of future HVDC grids. Several designs have been proposed for DC circuit breakers but few are suitable for Voltage Source Converter (VSC) applications. To date, only a few industrial prototypes have been developed, which are seen to be suitable for the VSC HVDC applications. This paper presents analysis and simulations on one of these prototypes, the Proactive Hybrid Circuit Breaker (PHCB). Equations are derived from a state-space analysis of the circuit breaker. A model of the circuit breaker is suitably parameterized for a +/- 300 kV VSC system in PSCAD. Fault simulations are then performed and compared to the equations developed in a state space analysis. Discussion is then given to the design and testing of the Load Commutation Switch (LCS).


[275] An Optimization-based Control Strategy for Modular Multilevel Converters: Design and Implementation

Nikola Stanković, Gilbert Bergna, Amir Arzandé, Erik Berne, Philippe Egrot and Jean-Claude Vannier

In this paper we present an optimization-based procedure for designing a reference circulating current which stabilizes the internal dynamics of a modular multilevel converter. This procedure relies on unconstrained convex optimization and it takes into account conflicting performance requirements such as reducing the oscillating components of circulating current and arm voltages. Tracking of such a reference signal is ensured by a robust tracking controller with gains chosen in order to attenuate the measurement noise. Since we were interested in implementation of the control algorithm by using a digital simulator, the design procedure is carried out in the discrete time domain. Effectiveness of the proposed strategy is confirmed on a prototype of three-phase modular multilevel converter with five sub-modules per arm and RL load.


[228] Photovoltaic Based Active Generator: Energy Control System Using Stateflow Analysis

Aimie Nazmin Azmi, Mohan Lal Kolhe

At present, most of the grid connected photovoltaic (PV) systems are operating at maximum power points and injecting power in uncontrolled way. Thus, active generator will be a good solution to support instantaneous power balance, frequency control and maintaining the power quality with controllable power injection. This new mode of active generator needs innovative power management. The new proposed energy control system for active generator might help to manage the energy within the micro-grid environment. In this work, the focus is to manage the energy among the PV based active generator, load and interconnected grid and energy controller architecture for that purpose is presented. It considers availability of the solar resources, storage system and load requirements. If there is lack of energy from the active generator, then the grid supplies remaining energy. For architecture of energy controller, Stateflow ® model is used. It uses available energy information from PV array, battery storage with super-capacitors and load requirements for managing the energy flow and it provides control signals to the power conditioning devices, which are used for integrating the sources. The presented energy management algorithm will be useful for the future smart grid system and also for building integrated PV based active generator system and demand side management.