Digital power electronics

High frequency switching circuits can effectively increase the power density, efficiency, reliability and flexibility, and reduce power losses and equipment cost. Consequently, high-frequency switching circuits have been paid much attention in recent decades. These performances are thoroughly different from traditional analogue control systems. Till now there is no suitable theory to describe the characteristics of the switching circuits and systems. A new theory entitled "Digital Power Electronics" presents the clue of switching operation (switching period T = 1/f, f is the switching frequency) and the pumping-filtering process, resonant operation and soft-switching methodology, and researched the rules of power switching circuits and systems. The new parameters Energy Factor (EF), Pumping Energy (PE), Stored Energy (SE), Capacitor-Inductor stored energy Ratio (CIR) and time constants x and tau(d). Using these new parameters, ZOH/FOH/SOH and the z-transform can well describe the characteristics of power switching circuits and systems.