On the use of current sensors for the control of power converters

Abstract

This paper describes the use of current sensors for the control of power converters. No voltage sensor is required in the whole system. The sensed current and the rate of change of the inductor current in different circuit topologies are used to determine the input and output voltages of the converters, and for current programming and maximum current protection. Apart from reducing the number of sensors, the proposed method provides inherent electrical isolation between the power conversion stage and the controller and lessens noise-coupling problems. The proposed technique is illustrated with a current-programmed dc/dc boost regulator with feedforward and feedback control. The regulator's steady state and transient responses under input source and output load disturbances are presented.