Autonomous AC Grid Based on Multi-infeed Voltage Source Converter Stations

It is desirable that remote isolated communities can become self-sufficient in electric power through harnessing energy from renewable energy sources. Taking advantage of the high controllability of voltage source converters, a scheme to realize a stand-alone AC grid for such an isolated community is examined. It uses voltage source converter stations as frequency changers. The multi-infeed voltage source converter design succeeds in the dual roles of maintaining the grid AC voltage while balancing real power generation and loads using local information only. The stability of the power system under the proposed control scheme, as affected by the control coefficients and operating conditions, is investigated. An analysis of eigenvalue sensitivity to control parameters is also included. Proof of the concept is carried by digital simulation studies.