一种带谐波补偿功能的DVR

提出了静止坐标下的谐振控制器,避开复杂的坐标变换方法,简单地检测出指定次数的谐波。应用这种静止坐标下的谐振控制器对指定次数的谐波电压进行闭环控制,简单的加到动态电压恢复器DVR(DynamicVoltageRestorer)系统中以达到谐波电压补偿功能,而对基本DVR的电压凹陷补偿性能的影响很小,提高了DVR的效率。分析谐振控制器的幅频和相频特性,指出在加入DVR控制系统中进行谐波补偿时不会引起有功功率的流动,对直流侧的能量影响较小。通过Matlab仿真确定了这种方法可以消除绝大部分指定次数的谐波。

Dynamic voltage restorer with harmonic compensation function

A resonant controller under stationary coordinates is proposed to detect the selected harmonics without complicated coordinates transform. It can be easily added into a DVR(Dynamic Voltage Restorer) control system to perform a closed-loop control for selected harmonic voltages for compensation to improve the efficiency of DVR,while its influence on voltage sag compensation performance is little. The amplitude- & phase-frequency characteristics of the resonant controller are analyzed,and it is proved that the steady state active power flow through DVR is kept close to zero and the influence on DC link voltage is little. Simulation with Matlab shows that the proposed method can eliminate most selected harmonic voltages.