基于非常规平衡电抗器的直流侧谐波抑制方法

In order to improve the ability of harmonic reduction in multipulse rectifier, this paper proposes a harmonic reduction method at DC link based on unconventional interphase reactor (UIPR). In this method, UIPR increases tap number of primary winding and one secondary winding on the basis of the conventional interphase reactor, which connects to the load through the primary tap control circuit and the secondary rectifier circuit. Furthermore, UIPR increases the pulse number of load voltage and the step number of the input line current, and decreases the total harmonic distortion (THD) value of input line current. Taking the minimum THD of input line current as the goal, the operation mode and optimal parameter design method of UIPR are analyzed. Experimental results verify the correctness of the theoretical analysis. After using UIPR, the load voltage of parallel connected multipulse rectifier can be increased from 12 pulses to 24, 36 and 48 pulses, and the THD of input line current is reduced from 15.15% to 3.81%. The harmonic reduction performance of the multipulse rectifier has been significantly improved.