Hybrid topology for voltage regulation applied in three-phase four-wire micro hydro power station

This paper deals with the development of a new hybrid topology for voltage regulation in micro hydro power station using self-excited induction generation applied in three-phase four-wire systems. The proposed topology is a combination of a three-phase four legs static synchronous compensator (STATCOM) and capacitor banks connected in parallel to the AC voltage bar. It is considered a three wires generator with no accessible neutral point being the neutral terminal for the load created through the neutral terminal of the excitation capacitor and the controller, which provides the choice to connect the loads either star or delta configurations. A control algorithm and a project for the variable capacitors are proposed based on the specifications of the STATCOM. The proposed generating system is modeled and simulated in MATLAB. Simulation results and preliminary experimental results are presented to demonstrate the performance of the proposed new hybrid method for the voltage regulation of the self-excited induction generator as well as to demonstrate the capability of an isolated generating system for feeding three-phase balanced loads.