A simple high speed sensorless method for PWM converter

This paper describes about a simple construction of high speed source voltage sensorless method of a PWM converters. It has the following characteristics: (1) this sensorless method is realized only by adding two operational amplifiers for one phase and a one analog switch to a conventional PWM control circuit. Therefore, this method makes low cost and simple; and (2) by using a high speed PI circuit of source current control, a high speed response of a estimated source voltage is also obtained. It not only obtains excellent performances such as 99% power factor and 1.9% THD but also realizes small size, simple control construction and the low cost converter. It can be also applied to an active filter.