Harmonic Impact and Optimization of Distributed Generation

A comprehensive study is made to compare the harmonic distortion produced by the different types and number of distributed generation (DG) units in a low voltage distribution system. Here three types of DG units are considered namely a mini hydro power wind turbine doubly fed induction generator and photovoltaic system. To determine the maximum allowable penetration level of inverter based DG harmonic resonance phenomena and harmonic distortion limits are also considered. To control harmonic propagation in a distribution system with DG units an appropriate planning of DG units is considered by determining optimal placement sizing and voltage control of DG units. Thus an effective heuristic optimisation technique such as improved gravitational search algorithm (IGSA) technique is also developed for determining the optimal placement sizing and voltage control of DG units in a radial distribution system.