PRECISION SIMULATION OF PWM CONTROLLERS

High frequency pulse width modulation (PWM) on large power system voltage sourced converters (VSC) and their controls place high demands on precision in simulation. A method of valve firing using interpolated switching was developed (IPST’99) to avoid very small calculation time steps (in the order of 1μsec). Further improvement to interpolated switching in the form of Instantaneous Solution has been developed to avoid numerical losses in PWM controllers.