METHOD FOR FORMING VOLTAGE AND CURRENT CONTROLLER OF PWM CONVERTER

摘要

PURPOSE: A method for forming a voltage and current controller of a PWM(Pulse Width Modulation) converter is provided to obtain an optimum gain of a PI controller of a synchronous coordinate system by calculating quantitatively the bandwidth according to the system driving capacity. CONSTITUTION: A low frequency model forming process is performed to form a generalized low frequency model indicated as a synchronous coordination system of a converter. A DC model and an AC model forming process is performed to form a DC model and an AC model by using the low frequency model including a perturbation component. An input voltage calculation process is performed to calculate a voltage of an input terminal of the converter by changing the effective current to the momentary current. A system model forming process is performed to form a system model of the current controller by arranging the conditions for the perturbation of a power frequency, the perturbation of load, and the unit power factor control. A voltage of a DC terminal and the current of an orthogonal current component are formed by defining a control rule to track the reference current of a PI controller of a synchronous coordinate system. A transfer function of the current controller is obtained by using the voltage of the DC terminal and the current of the orthogonal current component. A gain of the current controller is obtained. A rising time and a cutoff frequency are calculated.