ΛΛVoltage control of SEIG using D-STATCOM and DFIG: a comparative study

The advancements in power electronic devices have increased the ability of controlling the reactive power flow in the network. This is achieved by using facts devices with advanced control strategies. In recent years, reactive power supplying capabilities of DFIG is also exploited. SEIG is a well-known wind generator configuration used in both isolated and grid connected modes. SEIG experiences a problem of voltage instability during varying wind speeds and load conditions, which shows a negative impact on the connected network. The reactive power requirement supplied by an external source can assist the generator in operating in stable regions. In this paper, a detailed analysis is done to examine the superiority of DFIG over D-STATCOM in voltage control of SEIG. For this, a novel equivalent capacitance model of DFIG is derived to explain reactive power handling capabilities of DFIG. Two indices, average voltage profile and RUVMN, are used to compare the operational advantages of both techniques. The analysis is done with varying wind speeds, and results show that voltage control with DFIG is better when compared to D-STATCOM.