Steady-State Characteristics of the Six-Pulse Bridge Rectifier with Input Filter

A systematic and accurate method is described for the calculation of the harmonic content of the six-pulse bridge rectifier with input filter. Both the converter output ripple and input distortion are included in the calculations. The accuracy of the results is verified by experiment. It is shown that, under certain conditions, the output ripple can be neglected, leading to derivation of simple and explicit formulas for the converter harmonics. Based on the approximate formulas thus developed, major effects of the input filter on the converter characteristics are discussed and graphically shown. It is found that the control range and the firing angle need to be redefined compatible with the characteristics tics of the rectifier in the presence of the input filter. In addition, the maximum active power delivered to the load is determined by the filter rather than the load.