一种基于通用信号延迟叠加算子的单相电网基波及谐波同步算法

Single-phase Grid Fundamental and Harmonic Component Detection Method Based on Generalized Delayed Signal Superposition

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。

Grid synchronization has always been a great challenge for control systems of the single-phase grid-connected power electronic converters under distorted grid conditions and how to extract the fundamental and desired harmonic information quickly and accurately is quiet essential. A single phase fundamental and harmonic detection method based on generalized delayed signal superposition （GDSS） operators was proposed for estimating both the fundamental and selected harmonics under adverse grid conditions. The proposed method consists of multiple GDSS operators which are rather selective and it can extract the fundamental and wanted harmonic out of the input signal within half the fundamental cycle. Additionally, the parameters and number of GDSS operators can also be flexibly designed according to specific requirements of the control system. Simulation and experimental results under different grid conditions were presented to verify the performance of the proposed method and also its robustness regarding to different grid perturbations.