提出一种用于单相并网逆变器的并网电流滞环控制策略,其工作原理为:设置固定的采样周期,在每个采样时刻采集实际的并网电流并与给定电流相比较,根据比较结果直接获得各个开关管的控制信号进而实现对并网电流的控制.推导了开关周期以及电流纹波随并网电流电角度的分布规律,给出了滤波器参数设计准则.给出了电网电压、并网电流以及各个开关器件工作状态的暂、稳态仿真和实验波形,结果表明,该方法通过合理选取采样频率,无需复杂的并网电流线性闭环控制算法,在获得优良的并网电流控制性能的同时,有效限制了开关器件的最大开关频率,具有算法简单、易于实现、可靠性高等优点.%A hysteresis control strategy of grid-connected current is proposed for single-phase grid-connected inverter, which samples the actual grid-connected current at a fixed period and compares it with the reference current to generate the control signal of switching component for controlling the actual grid-connected current. The distribution law of switching cycle and current ripple corresponding to the electrical angle of grid-connected current is derived and the principle of filter parameter design is given. The steady-state and dynamic simulative and experimental waveforms of grid voltage and grid-connected current,as well as the working states of switching component,are shown,which indicates that,without complicated linear close-loop control algorithm,the grid-connected current is well controlled by properly selecting the sampling frequency, the maximum switching frequency of switching component is effectively limited, and the implementation of the proposed strategy is simple,with high reliability.
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