Load frequency stabilization of stand-alone hybrid distributed generation system using QOHS algorithm

Abstract

The proposed work studies the frequency stability of the identified hybrid power network (HPS) model with the integration of RESs and ESDs. The research work depicted here includes load frequency issue pertaining to isolated mode of operations with uncertainties in power oscillations of wind and solar energy. The studied HPS model is constitute of three wind turbine generators, two solar thermal generators, three diesel engine generators, an aqua electrolyzer and two fuel-cells as generating units while battery energy storage system, flywheel energy storage system and ultra-capacitor as back-up energy sources. A centralized control scheme using PID controller is employed for the controller design problem and its parameters are tuned by a nature inspired Quasi-oppositional Harmony Search (QOHS) algorithm. The three scenarios as step change, step change with stochastic effects and firm model of wind velocity, solar radiation and load demand are studied for the load frequency control dynamic performance. The execution of suggested QOHS based PID controller is contrasted with the studied optimization techniques. It may be inferred that the RESs and ESDs feeding isolated loads are properly operated to attain the coveted level of system frequency by using the QOHS technique.