单相并网模型电流控制及数字延时影响研究

摘要

并网逆变器作为电能变换的重要一环,其控制算法显得尤为重要.针对单相L型并网逆变器将模型电流控制应用其中,得到了一种参数易于整定的逆变并网控制算法且适用性强.为满足工程实践要求,分析了数字控制延时对系统稳定性的影响,并给出了控制参数修正方法;同时在计算并网逆变器给定输出电压时,对于数字控制延时的影响给出了电网电压反馈值合适的相位补偿.最后通过仿真与实验验证了模型电流控制的适用性及补偿数字控制延时影响的有效性.%The control algorithm of grid-connected inverter is particularly important in power conversion.The model based current control to the single-phase grid-connected inverter with L-type filter is applied.A kind of control algorithm which is easy to set parameters is obtained and its applicability is strong.The influence of digital control delay on the stability of the system is analyzed and the control parameters are modified.Meanwhile,the appropriate phase compensation of the grid voltage feedback value is given in order to overcome the digital control delay.Finally,the applicability of the model based current control and the correctness of the influence of the digital control delay on the system are verified by simulation and experiment.