Optimization for Customized Power Quality Service in Multibus Microgrids

Power quality requirements for different consumers and electric equipment are distinctive. Conventionally, common power quality standards are applied to the whole power grid inducing debate between technical commissions. Customized power quality standards for different consumers become a widely accepted solution. The main challenge is on the proper regulation of power quality in different areas. This paper considers a multibus microgrid system, where the power quality in each area has individual adjustable standard. Voltage unbalance, induced by connection of single-phase loads, is taken as the example. Distributed generators are utilized to reduce the negative-sequence voltage on consumer side. An optimization-based strategy is proposed and implemented with the power converter control system. A general mathematical model is established, which can be used in the optimization problem for evaluating the objective function. Peak current of each distributed generation is considered as the main constraint. Simulation is conducted to demonstrate the effectiveness of the method.