Characteristic Analysis of Three-Phase Diode-Bridge Rectifier with a DC Side Capacitor

The three-phase diode-bridge rectifier (TDR) with a DC side capacitor composed of only the diode and the capacitor is widely utilized in various industrial fields for its structural simplicity and low cost. However, its power factor is bad due to distorted waveform of the input current and the circuitry synthesis has been done in empirical trial and error ways until now. Therefore, for intending to give a solution to this, this paper presents a systematic analytical method obtaining rigorously quantitative result.Overall characteristics of TDR are strictly analyzed by using a parameter of the phase angle. This parameter is decided by the capacitor and load resistance. There exist current continuous and discontinuous modes, and an analytical result of the current of the capacitor gives an important indicator for the selection of the capacity of the capacitor. Analytical results are verified by the experiment.