具有馈电功能的并网UPS系统中锁相环的研究

Research on PLL by Applied to UPS System With Feeding Function

设计了一种带馈电功能的新型并网不间断电源(UPS)系统。为减小并网UPS系统中PWM馈电模块自身的传输时延和锁相环(PLL)的时延问题,系统对传统PLL进行了改进。将PWM馈电模块输出的电流信号和电网电压信号构造成瞬时功率,作为PLL的给定量,从而进行锁相。另外,将PLL前端使用单调谐滤波器(STF),以便过滤电网电压。仿真和实验结果表明,PWM馈电模块输出的并网电流相位能精确地跟随电网电压相位。

A new grid-connected uninterruptibe power supply （UPS） system is proposed.It improves the traditional phase locked loop（PLL） based on instantaneous reactive,and the output voltage of the PWM feed module and the grid voltage are constructed simultaneously into the sine signal and cosine signal supplied to the PLL as a given quantity for reducing PWM feed module of grid-feed UPS system own transmission delay and PLL own latency issues.In addi- tion,the PLL uses the self-tuning filter （STF） in front of it.It will filter the grid voltage.The simulation and experi- mental results prove that the PWM feed module output current phase can follow the grid voltage phase precisely.