Using Dynamic Phasors to Model a Single-Phase Active Rectifier Based on Lyapunov Current Control

To ensure low harmonic pollution in power systems, the restrictions on total harmonic distortion (THD) produced by AC/DC converters are being made more stringent by utilities. Single-phase active rectifiers are among the power electronic conditioning devices used to ensure that loads meet the utility THD limits. Linear control schemes based on proportional-integral (PI) controllers are commonly used in single-phase active rectifiers due to ease of tuning. However, linear controllers do not provide global asymptotic stability. Lyapunov-based nonlinear control strategy enables converters to have global asymptotic stability. However, most models of Lyapunov-based single-phase active rectifiers in the literature appear in a detailed form. Detailed models require relatively large computational effort to give accurate results. In this paper, a single-phase active rectifier based on Lyapunov inner current and load current feedforward control schemes is modeled with dynamic phasors (DPs). The Lyapunov function is derived from the most dominant harmonic in each state variable. Simulation results show that the DP model is about 220 times faster than a detailed switching model. There is a close match between the DP and detailed model results. The proposed DP model is useful for the fast-paced study of multi-active-rectifier-converter systems.