Converter control of PMSG wind turbine system for inertia-free stand-alone microgrid

Abstract

This paper proposes the new converter control of the permanent magnet synchronous generator (PMSG) wind turbine system in the inertia-free stand-alone (IFSA) microgrid with the only converter-based-generators (CBGs). Instead of applying the conventional real and reactive power controller, the more robust controller is required in the IFSA microgrid because it is subject to a weak system such that its frequency is determined by the switching control of CBGs. The proposed controller has the grid-side converter, which controls to keep the voltage magnitude and phase angle of the point of common coupling (PCC) in a stable mode. It balances the real power between output power of wind turbine system and the load demand. Also, the machine-side converter controls rotor speed and pitch angle, which proposed to balance the active power flow, thus maintaining the converter DC-link voltage. The electromagnetic transients program (EMTP) based simulation results are given to verify the effectiveness of proposed controller in the IFSA microgrid. Also, its effectiveness is verified with the experimental test by the real-time digital simulator (RTDS).