Dynamic behavior of single-phase full-wave uncontrolled rectifiers with instantaneous constant-power loads

Behavior of single-phase full-wave uncontrolled rectifiers with instantaneous constant-power loads (CPLs) is described. A second order rectifier filter is used in the analysis. Rectifiers with CPLs may occur in distributed power architectures that are fed by ac sources. CPLs introduce an inverse-voltage term, which could cause output-voltage collapse, and thus render the rectifier system unstable. In particular, stable operation of the rectifier system is dependent on its initial condition and circuit parameters. A necessary condition for stable operation of the rectifier system is, thus, derived. This paper also studies input (power factor) and output characteristics of the rectifier with a CPL, and makes comparisons with the conventional resistive load case. An approximate expression for the output voltage ripple is given for high-enough values of filter capacitance. Furthermore, a more complete mathematical model for the rectifier system is used to incorporate line-voltage distortion. Simulation and experimental results are included for verification.