基于虚拟磁链和锁相环的无电网电压传感器并网逆变器的研究

基于虚拟磁链和锁相环的无电网电压传感器并网逆变器的研究:为了提高并网逆变器的可靠性和抗电网电压波动，同时进一步降低并网逆变器的成本，提出了一种基于
锁相环和虚拟电网磁链的无电网电压传感器的控制策略。根据并网逆变器在同步旋转坐标系下的数学模型，采用虚拟的电网磁链矢量定向的矢量控制和d、q 轴电流闭环控制，这样实现了d、q 轴电流的解耦控制，使q 轴电流控制有功功率，d 轴电流控制无功功率。实验结果看出：采用虚拟的电网磁链矢量定向的并网逆变器具有良好的动、静态性能。从而验证了该方案的可行性和正确性。
ABSTRACT: In order to improve reliability and resist grid voltage fluctuation, and further reduce the cost for the grid-connected inverter, the control strategy is presented based on phase lock loop(PLL) and virtual grid flux without grid voltage sensors. The virtual grid flux vector orientation and d-axis current and q-axis current close-loop control are used based on the mathematical model in synchronous rotating frame for the grid-connected inverter, which realizes the decoupling control for d-axis current and q-axis current. The acitve power and the reactive power are independently controlled by q-axis current and d-axis current. Experimental results show that the grid-connected inverter based on PLL and virtual grid flux has good dynamic and static performance. So the feasibility and correctness for the control strategy is verified.
关键词：锁相环；虚拟电网磁链；无电网电压传感器；解耦控制；电流闭环
KEY WORDS: PLL; virtual grid flux ; without grid voltage sensors; decoupling control ;current close-loop