双模式逆变器独立供电稳定性能控制策略研究

摘要

The droop control strategy is often adopted in the independent operation of the grid connected / independent dual mode inverters in micro-grid.Aiming at the problems existing in the traditional droop control strategy,such as large fluctuation of output voltage frequency and amplitude,and the PI control strategy under the dq coordinate system is often used to control the voltage,the voltage and current coupling causes the algorithm to become complex.Two schemes of quasi proportional resonant (QPR) control and proportional complex integral (PCI) control methods are proposed to introduce to the droop control strategy.The two control algorithms based on the αβ coordinate system need not be decoupled,the algorithm is more simple and can effectively restrain the voltage fluctuation.The simulation results in Matlab/Simulink environment show that the two control schemes can obviously reduce the fluctuation of voltage frequency and amplitude.Further comparison shows that the droop control strategy with the introduction of PCI is faster and the output power and voltage is more stable.%微网中并网/独立双模式逆变器独立运行时常采用下垂控制策略,由于采用传统下垂控制策略时输出电压频率和幅值波动较大,以及电压控制采用dq坐标系下的PI控制策略引起电压电流耦合导致算法复杂的问题,提出将准比例谐振(QPR)控制和比例复数积分(PCI)控制引入下垂控制策略两种方案,基于αβ坐标系的这两种控制算法无需解耦,算法更加简单且能有效抑制电压波动.Matlab/Simulink环境中的仿真结果表明,两种控制方案都能明显减小电压频率和幅值的波动,进一步比较发现引入PCI的下垂控制策略响应速度更快,输出的功率和电压更加稳定.