Multiple Feedback Loop Control Research Of Microgrid Inverter

In this paper, under the background of the micro-grid,according to the problem thatwhen the micro-grid in independent operation needs to provide their own voltage andfrequencey, and that the micro-grid switching between grid-connected model andislanding model needs to change control mothed ,carried out theoretical research onmicro-grid inverter control method, and focus on analysis of the method of multiplefeedback loop control based on droop characteristics. Through the analysis of multiplefeedback loop control method, find that the inverter output impedance influenced byvoltage and current loop PI parameters, and design PI parameters to make the inverteroutput impedance as an inductance impedance, therefore, the droop control method usedin high-voltage system can be used in micro-grid. Through using the Matlab simulationsoftware on the multiple feedback loop control method of simulation, come out thismethod could achieve providing voltage and current security for the system when themicro-grid in independent operation, and ensure load normal work; Besides,could achievethe micro-grid smooth switch between grid-connected model and islanding model withoutchanging the control method; And when multiple inverters paralleled operation enablepower sharing between the micro sources in the micro-grid, and achieve plug and play ofdistributed power suply.The experiment use DSP digital control tecnology, and write the control program. On3kW three-phase inverter platform make experiments on open loop and single currentclosed loop, make preparation for the next step multiple closed loop experiment.