New modified water cycle optimized fuzzy PI controller for improved stability of photovoltaic-based distributed generation towards microgrid integration

Abstract

In this paper, a new modified water cycle (WC)-based optimization is incorporated for independent distributed generation controllers’ (IDGCs’) gain parameters tuning. Photovoltaic (PV)-based distributed generation (DG) is considered for active distribution network/microgrid tied operation, where the IDGC feedback path is designed with fuzzy Proportional-Integral (PI) scheme. The PI controller is linear and hence unable to address operational uncertainties (e.g. variation in irradiation profile, partial shading, symmetrical/asymmetrical faults, load variations, etc.) for a PV-based DG incorporation. The fuzzy rule-based adaptive gains are also limited towards unbounded uncertainties (grid connected to autonomous mode operation). Thus, to improve the system stability with effective feedback gain parameters’ selection, the modified WC algorithm is designed in this paper. The proposed WC scheme is included with a sinusoidal chaos map to address the nonlinearities. The performance of the proposed IDGC feedback path is evidenced under various grid operational contingencies. The efficacy measure of proposed scheme is recorded in terms of dynamic oscillation damping. This performance validation is implemented in MATLAB Script environment.