A phase-difference angle control-mode PWM high-frequency resonant inverters using static induction-transistors and-thyristors

Power Conditioning and Processing of voltage-fed series resonant inverters and converters using Static Induction Devices are actually performed in terms of operating frequency control or fixed frequency variable voltage control schemes by the authors. These control methods have disadvantages of either restricted power control range or unreliable switching operation. The authors propose a new combined control-based on the basis of a phase-shifting angle control-mode PWM strategy between left and right switching arms of the series resonant full-bridge inverter with an adaptive frequency servo regulation function for maintaining switching-device operating-mode in a reliable-and an efficient condition. Practical implementation of this control circuit is described that utilizes two channel phase-locked loop systems together with a frequency tracking system by a resonant zero-cross current detection scheme. A novel type of high-power series resonant PWM inverter using Static Induction-Transistors and-Thyristors, which stably operates in a frequency range of 30 KHz to 100 KHz or more, is demonstrated for induction-heating and-melting, and DC-DC Converter. The simulated results and its performance characteristics in steady-state are described as compared with the experimental results.