Discrete State Event-Driven Framework for Simulation of Switching Transients in Power Electronic Systems

Accurate and efficient simulation of device-level switching transients together with system-level dynamics in power electronic systems is challenging due to stiffness and intensive discontinuous points introduced by discrete system events. In this paper, a switching transient simulation mechanism is proposed to combine the discrete state event-driven (DSED) simulation framework and the piecewise analytical transient (PAT) model together to overcome such difficulties. Key elements of this simulation framework for switching transient simulation include: 1) a commutation-unit-based (CUB) method for switching transient simulation and 2) a time-scale-decoupling (TSD) simulation mechanism. The proposed simulation framework is applied to a 50kVA solid-state transformer (SST) to verify its accuracy and efficiency. DSED simulated and experimental waveforms are in excellent agreement. Up to 5.3-fold and 717.3-fold improvements in simulation speed are achieved at the same level of accuracy compared with Simulink (R) simulation with ideal switch models and Saber (R) simulation with physics-based device models, respectively.