基于VSG的正弦锁定技术研究

为了实现新能源系统中各并网运行设备的实时同步,采用了一种不需要进行滤波器设计且计算量小的正弦锁定器技术。本文通过虚拟同步发电机的控制思想模拟同步发电机的运行情况,控制其与电网的功率交换为0,实现对电网输入信号幅值、频率及其相位的同步。仿真分析可知,在输入信号发生阶跃突变时,由于虚拟惯性的存在其输出信号不发生瞬时突变;当输入电压信号中含有幅值为10%基波的2、3、5次谐波成分时,正弦锁定器的输出电压总谐波畸变率从增强型锁相环条件下的4.28%减小到0.01%,有效的验证了正弦锁定器的抗谐波干扰能力。

Research on Sinusoid-locked Technology Based on Virtual Synchronous Generator

In order to realize the real-time synchronization of various grid-connected operation equipments in new energySsystem, this paper adopted a effectively sinusoid-locked loop technique which do not need to design the filter and the advantage of less calculation. This paper based on the control concept of virtual synchronous generators which mimicking the operation of synchronous generators, by controlling the power exchange to be zero to get the synchronised signal of input amplitude, frequency and phase signal. Finally through the contrast analysis with enhanced phase-locked loop in the platform of Matlab/Simulink, the sinusoidalSphase-locked loop technologySbecause of the existence ofSvirtualSinertiaShas the characteristics of that outputSsignalSdoes not occur instantaneous mutations, the smallSimpact to circuit,Sand this method does not affect theSdynamicSresponse speed of the system at the same time when the input signalSstepSmutation; the output voltage total harmonicSdistortionSrate from 4.28% under the conditions of the theSenhancedSphase locked loopSreduced to 0.01% which under the conditions of the sinusoid-locked loop technique when the input voltageSsignalScontainsS2nd,S3rd,S5th order harmonic components which the amplitude is 10% of the fundamental wave,Swhich effective verifiedSthe capacity of resisting harmonicSinterference of sinusoid-locked loop technique.