Single-loop voltage and frequency control of stand-alone three-phase four-wire renewable energy conversion system with battery storage

In this paper, single control loop based scheme for regulation of voltage and frequency of Self Excited Induction Generator (SEIG) based stand-alone 3-phase 4-wire renewable energy conversion system under source and balanced/unbalanced load perturbations is presented. The regulation is accomplished by maintaining reactive and active power balance across individual phases of SEIG using a Generalized Impedance Controller (GIC). GIC is a PWM voltage source converter with battery at its dc-bus, having controlled four-quadrant equivalent impedance. Unique feature of the scheme is successful control of both amplitude and frequency of the SEIG terminal voltage using only 3-phase stator voltage feedback and no frequency feedback. A mathematical model of the SEIG-GIC-Load 3-phase 4-wire integrated system has been developed and simulated in MATLAB/Simulink to validate practicability of the generating system under variety of source and load perturbations.