Analysis of the performance of hybrid AC/DC microgrid by using d-q Transformation

摘要

Distributed generators based on wind and solar energy will give prominent momentum in near future [1]. A microgrid consists of group of loads and distributed generators that operate as a single controllable system. The microgrid concept introduces hybrid AC/DC microgrid which reduces multiple reverse conversions in an individual AC or DC grid. This project aims at providing a reliable control system for integrating small renewable power generating units with main grid. The control system designed in this work consist of inner current loop and outer voltage control loop collectively known as Multiloop current voltage PI control system. In this work the performance of the hybrid AC/DC microgrid is analysed by using this control system along with d-q Transformation. This method is implemented for the converters to properly co-ordinate the AC sub-grid and DC sub-grid. The circuits with the proposed method are modeled and simulated by using the MATLAB/ SIMULINK. The results show that with this technique, phase and frequency of the converters are synchronised with that of the utility grid. Hence the reactive power in the transmission line is reduced‥ As the reactive power is reduced, we obtain a stabilized output power which is transmitted to the loads and utility grid by using the above proposed method.