Design Optimization and Reliability Enhancement of Community Based Islanded Microgrid through Frequency Stability

This paper investigates a new strategy for voltage and frequency control of isolated and autonomous Microgrid. In this study Microgrid consists of energy storage, renewable energy based sources that consists of solar pv, microhydro and Biomass with their respective power electronics converters. We have chosen multiple options and tried to find-out the trade-off among cost, stability, reliability and the availability of renewable resources. Strictly, for more stable and reliable operations, cost would be higher. Thus, we have proposed design of an off-grid solution such that all the power sources i.e. solar pv, biomass and microhydro will be stored and supplied through batteries using converters in order to ensure frequency stability for PV, microhydro and biomass. We have considered a two pronged approach i.e. 1) switch battery banks to dump the excess energy and maintain the frequency of the system (similar to dummy loads in electronic load controller - an electronic governor for microhydro). 2). Energy from microhydro can either be used directly or through batteries. Where, the biomass will always be used from batteries and as a backup source. System has been modelled for different scenarios by using MATLAB/SIMULINK. The results verify that system can work in stable state under changing conditions.