In renewable power generation systems,ensuring the synchronization of the inverter and the power grid is crucial for the stable operation of grid-connected inverters.Nowadays,the phase-locked loop(PLL)technology has b...In renewable power generation systems,ensuring the synchronization of the inverter and the power grid is crucial for the stable operation of grid-connected inverters.Nowadays,the phase-locked loop(PLL)technology has become a widely used grid synchronization method because of its simple implementation and robustness under various grid conditions.Even though a lot of PLLs have been proposed,an overview and comparative analysis of multiple PLLs can be helpful for practical applications.In addition,the weak grid condition is a great challenge for the system.Therefore,this study first presents an overview of the existing PLLs together with their general structures and basic working principles.Depending on the implementation of the phase detector,the PLL can be divided into three categories:power-based PLL(pPLL),orthogonal-signalgenerator-based PLL(OSG-PLL)and adaptive-filter-based PLL(AF-PLL).Then,from the above classification,seven typical single-phase PLLs are selected for further study.Finally,some test results are given,and a comprehensive evaluation of the selected PLLs under different grid conditions is conducted.展开更多
如何在单相畸变电网中快速准确的获取基波以及所需的特定次谐波信息,对并网型电力电子变换器的控制系统而言是十分重要的。针对这一问题,提出了一种基于通用信号延迟叠加算子(generalized delayed signal superposition operator,GDSS)...如何在单相畸变电网中快速准确的获取基波以及所需的特定次谐波信息,对并网型电力电子变换器的控制系统而言是十分重要的。针对这一问题,提出了一种基于通用信号延迟叠加算子(generalized delayed signal superposition operator,GDSS)的单相锁相环结构,用于恶劣电网下系统基波以及多重谐波信息的检测。这种锁相环结构包含了多个具有很强频率选择特性的GDSS算子,能够在半个基波周期内从输入信号中分离出所需要的基波以及多个谐波频率信息,并且其参数以及GDSS算子个数还能够根据实际控制系统需求灵活调整。在各种工况下的仿真及实验表明,所提的锁相方法能够在恶劣电网下快速准确的获取基波及多重谐波信息,并且面对电网常见扰动时具有很强的鲁棒性。展开更多
基金This work is supported in part by the National Natural Science Foundation of China(No.51807089,51877104)in part by the Natural Science Foundation of Jiangsu Province(No.BK20180432).
文摘In renewable power generation systems,ensuring the synchronization of the inverter and the power grid is crucial for the stable operation of grid-connected inverters.Nowadays,the phase-locked loop(PLL)technology has become a widely used grid synchronization method because of its simple implementation and robustness under various grid conditions.Even though a lot of PLLs have been proposed,an overview and comparative analysis of multiple PLLs can be helpful for practical applications.In addition,the weak grid condition is a great challenge for the system.Therefore,this study first presents an overview of the existing PLLs together with their general structures and basic working principles.Depending on the implementation of the phase detector,the PLL can be divided into three categories:power-based PLL(pPLL),orthogonal-signalgenerator-based PLL(OSG-PLL)and adaptive-filter-based PLL(AF-PLL).Then,from the above classification,seven typical single-phase PLLs are selected for further study.Finally,some test results are given,and a comprehensive evaluation of the selected PLLs under different grid conditions is conducted.
文摘如何在单相畸变电网中快速准确的获取基波以及所需的特定次谐波信息,对并网型电力电子变换器的控制系统而言是十分重要的。针对这一问题,提出了一种基于通用信号延迟叠加算子(generalized delayed signal superposition operator,GDSS)的单相锁相环结构,用于恶劣电网下系统基波以及多重谐波信息的检测。这种锁相环结构包含了多个具有很强频率选择特性的GDSS算子,能够在半个基波周期内从输入信号中分离出所需要的基波以及多个谐波频率信息,并且其参数以及GDSS算子个数还能够根据实际控制系统需求灵活调整。在各种工况下的仿真及实验表明,所提的锁相方法能够在恶劣电网下快速准确的获取基波及多重谐波信息,并且面对电网常见扰动时具有很强的鲁棒性。
