A novel harmonic-free three-phase diode bridge rectifier applying current injection

A novel harmonic-free three-phase diode bridge rectifier is proposed in the paper. Low distortion of the input currents is obtained applying optimal current injection. The optimal current injection is discussed, and requirements it imposes to the current injection network are derived. A class of simple current injection networks, consisting of a transformer, two capacitors and a number of resistors or resistance emulators is proposed. Power processed by the resistors or resistance emulators is shown to be 8.81% of the input power. Design of the current injection network is discussed, and dependence of the input current distortion on the applied capacitors is analyzed. Volt-ampere rating of the transformer is shown to be only 0.16% of the input power. Analytical results are experimentally verified.