Input resonance investigation and LC filter design for PWM Current Source Rectifiers

The input LC resonance is a consideration in the filter design for Current Source Rectifiers (CSR). One challenge in this design is that the rectifier system can have a range of total equivalent line inductance on the CSR ac side due to the variable inductance from the power system. Furthermore, it is found in this paper that the CSR dc side circuit can also affect the input resonance. These factors may lead to an unexpected LC resonance on the CSR input side. One approach to address this issue is to increase the filter size. However, optimized design and performance cannot be guaranteed in this case. This paper investigates the input resonance of a pulse-width-modulated (PWM) CSR systematically and proposes a procedure for input filter design which can avoid the unexpected LC resonance on the CSR ac side. The proposed strategy results in a better system performance and less sensitivity to the source inductance from the power system. The designed methods are validated by the simulation and experiment results.