基于数字锁相环的并网逆变器电流跟踪控制

针对光伏并网发电系统，基于数字锁相环，研究了一种实现系统并网电流幅值、相位跟踪控制的新方法。光伏并网系统的电压和电流信号经传感器和模／数转换后送人数字锁相环，得到该模拟信号的幅值、相位。在此基础上，通过PI算法实现并网电流幅值和相位的跟踪控制。实验结果表明，该方法在系统原有基础上无需添加任何硬件设备，便可高效、快速、准确、可靠地实现逆变电流幅值和相位跟踪控制。

Current Tracing Control of a Grid-Connected Inverter Based on Digital PLL

Based on a new digital PLL, a new current tracing control strategy for a grid-connected PV system was proposed to control the amplitude and phase of the inverter current. Using the sensors and A/D, the signals of the voltage and current in the PV system were sent into the digital PLL, then the amplitude and phase of the signals were got. Based on the amplitude and phase information, PI algorithm was used to control the amplitude and phase of the inverter current. Experimental results were presented to demonstrate the effectiveness of the proposed strategy.