A New Power Analysis Method of PWM Rectifier with Unbalanced Voltage Condition

The thesis puts forward a new calculation method of tri-dimension instantaneous complex power based on coordinate conversion and symmetrical components.According to the instantaneous complex power,system input power could be decomposed as 12 power components,such as:instantaneous active power、reactance capacity between the axes of q0,dq and d0,etc.Two kinds of control strategy that one aims to suppress negative-sequence current AC side,while the other aims to suppress the secondary harmonic of input AC side,are analyzed in the thesis based on analysis of instantaneous power.The thesis has constructed a PWM rectifier simulation platform based on Saberr and has presented various waveforms of instantaneous active power,instantaneous reactance capacity,instantaneous power-factor and input current etc.By adopting different optimizing control algorithm in every unbalanced input case.These provide a firm theory base for the power analysis and optimizing control of the three-phase PWM rectifier in the case of unbalanced input.