High-frequency chopper soft switching voltage regulating circuit

Abstract

The invention discloses a high-frequency chopper soft switching voltage regulating circuit, which includes an auxiliary chopper voltage regulating circuit, a main chopper voltage regulating circuit, aPWM drive control circuit and an output circuit. The auxiliary chopper voltage regulating circuit is connected with the main chopper voltage regulating circuit. The output circuit is connected with the main chopper voltage regulating circuit. The main chopper voltage regulating circuit and the auxiliary chopper voltage regulating circuit are also connected with the PWM drive control circuit. ThePWM drive control circuit controls the on-off of the main chopper voltage regulating circuit and the auxiliary chopper voltage regulating circuit. External input high-voltage DC power is input to theparallel structure of the auxiliary chopper voltage regulating circuit and the main chopper voltage regulating circuit. The chopper output passes through the output circuit and is then connected to acircuit load. Under the control of the PWM drive control circuit, an adjustable direct voltage and current are obtained on the output circuit. Under the control of the PWM drive control circuit, the soft switching process of a switching device is realized. Therefore, the loss of the switching device is reduced, and the safety of the circuit is improved.

Description

technical field [0001] The invention belongs to the technical field of high-frequency conversion circuits, in particular to a PWM voltage regulating circuit. Background technique [0002] The chopper circuit is used in a specific power circuit to change a specific direct current into another fixed voltage or adjustable voltage direct current to provide a switching power supply for the circuit. [0003] In power circuits, high-power semiconductor electronic devices are usually used as electronic switches to realize chopping. In high-frequency environments, high-power semiconductor electronic devices are often turned on at high voltages and turned off at high currents, that is to say, in high-frequency environments The switching devices are often in the hard switching state. [0004] The hard switching state has the following problems when the specific power circuit is running: First, the high-frequency on-off of the switching device will generate a large instantaneous power ...

AI Technical Summary

Problems solved by technology

[0004] The hard switching state has the following problems when the specific power circuit is running: First, the high-frequency on-off of the switching device will generate a large instantaneous power consumption in the inductive and capacitive load, and the total power consumption will increase with the switching frequency of the switching device. The excessive instantaneous power consumption will increase the junction temperature of the switching device, and the stability of the switching device will be threatened; secondly, the peak voltage or peak current generated by the high-frequency on-off of the switching device will cause secondary damage to the switching device. Breakdown; Finally, the high-amplitude voltage mutation and current mutation generated by the switching device during high-frequency on-off will also cause serious electromagnetic interference to the circuit, affecting the normal operation of the entire circuit

[0007] However, there is no mature and suitable technical solution proposed in the prior art on how to apply the above soft switching ideas to specific circuits to realize the soft on and off of the switching devices in the chopper circuit

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