Study On Double PWM Of Voltage Source Inverter Based On LingYang SPMC75

Power electronic equipment with rectifier is widely used in industry and daily life. In the equipment phase-controlled rectification or uncontrolled rectification is mostly employed for simplifying the AC-DC conversion stage.The method of phase-controlled rectifier has a slowly dynamic response and a low power factor in net side when system works in deep control.The method of uncontrolled rectifier has some disadvantages as follow: The rectifier imbibes distortion current from the net side and brings harmonic wave to the net; the energy of the DC side can't feed back to the net side so that reduce power factor.Nowadays there are two methods to limit harmonics and correct power factor:one method is passive power factor eorreetion, and the other is active power factor correction-The active power factor eorreetion is to adopt full controlled switching devices in the main circuit and pulse-width modulation to eliminate harmonic and improve power factor. Based on analyses a bi-direetional PWM reetifier with the active Power factor correction is designed.The thesis analyzes the principle of voltage source rectifier. What's more, it compares the kinds of PWM,deduces in detail the mathematic formulation of voltage source rectifier ,contrasts defeats and merits all kinds of control methods and analyzes the algorithmof two-phase modulation SVPWM. Then according to the systems control goal, the voltage and electric current double closed-loop control structure is used to carry on the control to the PWM rectifier.The PWM inversion uses the vector control to realize the electrical machinery velocity modulation and the torque control.Using MATLAB simulation software,the thesis simulate and analyze dynamic performance of scheme,to testify correction and applicability and to provide guidance of making sample.