Control Method for Three-Phase Rectifier with High Power Factor

摘要

A method for controlling a three-phase rectifier is provided to improve a power factor by stabilizing an output voltage in different conditions of a load. A conduction angle is controlled in order to determine a pulse width of a switch which has a three-phase diode rectifier and three two-way switches(S10). Load resistance and load inductance are computed by using the conduction angle, a fundamental component of line current and supply voltage flowing on a power supply(S20). The power factor of 1 is achieved by obtaining phase angle using output current, the supply voltage and the load inductance, determining a switching time of the two-way switches using the phase angle, and then making the supply voltage and the fundamental component of the line current be in phase(S30).