Varying duty cycle control for discontinuous conduction mode boost rectifiers

A novel control method for boost rectifiers to attenuate the low-order harmonics which are difficult to be removed by the input filter is presented in this paper. The duty cycle within a fixed switching period is varied such that the rectifier is operated at the boundary of the discontinuous and continuous conduction modes. Compared to the traditional discontinuous conduction control with a constant duty cycle, the proposed control strategy features advantages such as a higher power factor or equivalently, a smaller input filter, and a higher output voltage. Experimental results show good conformation with the theoretical analysis.