A disturbance predictive deadbeat control for unified series-parallel power quality compensators

A number of power electronic systems combine two or more power converters coupled to the utility in series or parallel. This paper develops a unified deadbeat controller for multiple-converter systems. The abc-aβ transformation decouples the converters into two single-phase equivalents, and allows the implementation of the proposed deadbeat control. A second order predictive method is used to estimate the supply voltage for feedforward compensation of the disturbance, and the inherent computing time delay caused by the deadbeat controller is compensated every two sampling periods. The resulting system equations are optimized to reduce the computational effort of the DSP controller. The theoretical predictions are verified.