Impedance sensitive STATCOM control for systems supported by renewable generation

Reactive power control is known to be an effective means of controlling voltage; however, for optimal performance, the system reactance must be known. Power systems with high renewable energy penetration have been known to have voltage stability issues. To further complicate this issue, distributed renewable sources are likely to have an effect on the local system impedance. As a result, connection and disconnection of such sources is likely to result in significant changes in system impedance. In this paper, impedance estimation is used to dynamically tune the controllers of a STATCOM so that consistent dynamic performance may be obtained. The method has been verified through simulation and through laboratory-based experimentation.