Enhanced power generation from two-winding single-phase SEIG using LMDT-based decoupled voltage and frequency control

Abstract

This paper proposes a leaky minimal disturbance theory (LMDT)-based decoupled control of voltage and frequency for two-winding single-phase self-excited induction generators (SEIGs) for enhanced power generation and power quality improvement. Single-phase two-winding SEIGs are normally designed with 33% derated capacity in comparison to three-phase SEIGs of the same frame size. Using single-point operation performed by the proposed decoupled voltage and frequency controller (DVFC), the two-winding single-phase machine can generate enhanced power output, nearly 33% higher than its normal capacity. It is equal to the power generated by a three-phase machine with the same frame size. The DVFC consists of a voltage source converter (VSC) and a closed-loop controlled dump load. A single-phase VSC is used for harmonics and fundamental reactive power compensation for system voltage control and harmonics mitigation. The control of VSC is achieved using an LMDT-based control algorithm. The minimal disturbance theory-based control algorithm is used for potentially fast convergence and fast dynamic response, whereas the leakage factor is added for improving the steady-state performance of the system. The LMDT control-based VSC-battery energy storage system scheme is also implemented for the voltage and frequency control of a single-phase SEIG. Both schemes are implemented in real time using a digital signal processor.