Implementation of Distributed Fuzzy Load Control to an Autonomous Wind Diesel System

Abstract

Many autonomous power systems are powered by diesel generators alone, which results in greater operating costs than interconnected grids. It is therefore desirable to integrate renewable energy sources such as wind into these mini grids. However, due to the fluctuating power generation from the wind resource, the varying load profile and the relatively low system inertia, technical difficulties arise in terms of system stability and efficient operation. Typically the penetration of wind energy on such systems is limited to 30%. Distributed intelligent load control can be used to increase wind penetration and cut diesel fuel consumption, whilst maintaining system stability. This thesis describes the development and application of a distributed intelligent load control system. The development of a self-tuning fuzzy controller and the construction of a laboratory wind-diesel test rig are discussed. The development of a dynamic Wind-Diesel computer model is also described. Finally the results of tests carried out on a Wind-Diesel system consisting of a 45kW stall regulated wind turbine and a 48kW diesel generator are discussed. The results were encouraging demonstrating that distributed fuzzy load control is a low cost and effective technique, which can be applied to small or large hybrid systems. The simulation results are developed by MATLAB.