Method for controlling uniform heating of switch device of switch power source

Abstract

The invention relates to the field of switch power source control, in particular to a method for controlling uniform heating of switch devices of a switch power source. The switch power source comprises a full bridge converter, the switch devices in the full bridge converter are switch tubes, the sequence of the switch devices in the full bridge converter alternately changes periodically, and the alternating period is N times of the switch control period of the switch devices, wherein N refers to a natural number larger than 2. Alternate soft turnoff of the switch devices is realized by alternately changing turnoff sequence of the switch devices composed of the switch tubes of the full bridge converter in the switch power source, so that the switch devices are uniform in heating within a long time period, and service life of the whole switch power source is prolonged.

Description

technical field [0001] The invention relates to the field of switching power supply control, in particular to a control method for uniform heating of switching devices of the switching power supply. Background technique [0002] With the development of industrial technology, the power supply has transitioned from the traditional thyristor power supply to switching power supply, and the application of switching power supply is becoming more and more extensive. There are many methods for DC converters in switching power supplies. In high input voltage or medium and high power converters, full bridge converters are often used. With the traditional hard switching technology, there are power switching tubes (such as IGBT, etc.) with large switching stress, large switching device losses, and low conversion efficiency. Especially for high-power power supplies for industrial applications, high power loss has a great impact on production costs, and high energy consumption also cause...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to overcome the problem of uneven heating of each switching device in a switching power supply comprising multiple switching devices, and to provide a control method for uniform heating of switching devices in a switching power supply that can make each switching device generate heat evenly and effectively prolong the life of the switching device , the switching power supply includes a full-bridge converter, the switching device in the full-bridge converter is a switching tube, and the switching devices that form the leading arm and the lagging arm in the full-bridge converter are combined in a periodic alternating transformation, which alternately The cycle is N times the switching control cycle of each switching device, that is, one alternate cycle includes N switching control cycles, and N is an even number above 2 (such as 2, 4, 6, 8, 10); the switching of each switching device The control cycle refers to the pulse switch control cycle in which the four switching devices of the full-bridge converter are turned on and off once respectively.

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