双反星形不控整流器的直流侧双无源谐波抑制方法

This paper proposes a dual-passive-harmonic-reduction method for double-star uncontrolled rectifier. In this method, a multi-winding interphase reactor is used instead of the inter-phase reactor, its primary winding and two common cathode diodes constitute a two-tap converter, its secondary winding and another two common cathode diodes constitute a single-phase full-wave rectifier circuit. These two passive circuits make up a dual passive harmonic reduction circuit. Under the effect of the dual passive harmonic reduction circuit, the double-star uncontrolled rectifier can increase the output pulse to three times the original value, and become an 18-pulse rectifier. In this paper, the working modes of dual passive harmonic reduction circuit is analyzed, and from the perspective of minimum THD of input line current, the multi-winding interphase reactor is optimized. Theoretical analysis shows that the THD value of input line current is reduced to 10.1% after using the dual passive harmonic reduction method, and the load voltage ripple is 7.56×10^-3. Simulation and experimental results verify the correctness of the theoretical analysis. Since only passive devices are adopted in this method, the circuit structure is simple and easy to implement.