Solution Set Analysis and Control Condition of Varying Duty Cycle Control for Discontinuous Conduction Mode Boost Rectifiers

摘要

The solution set analysis and control condition for regulated 1-switch boost rectifiers operating at the boundary of the discontinuous and continuous conduction modes is presented in this paper. Compared to the traditional discontinuous conduction control with a fixed switching frequency and a constant duty cycle, there are many advantages in varying duty cycle control, including higher power factor and least lower-order harmonic or equivalently, a smaller input filter, and a higher output voltage. However, the voltage ratio would be selected from the three roots of the cubic equation and the estimation must be made for one exact solution that matches the practice operation of the rectifier. According to the solution set analysis, the condition of varying duty cycle control is derived. Experimental results show good conformation with the theoretical analysis.