Method for suppressing bias magnetism of transformer matched with full-bridge inverter

Abstract

The invention relates to a method for suppressing bias magnetism of a transformer, and in particular to a method for suppressing bias magnetism of a transformer matched with a full-bridge inverter. The problem of poor reliability or complicated hardware circuit structure of an existing bias magnetism suppression method is solved. According to the method, currents of a primary side of the transformer at a positive half-cycle peak and a negative half-cycle peak are respectively sampled, current closed-loop proportional integral differential (PID) control is performed on the currents of the primary side in a positive half period and a negative half period, a switch tube in the positive half period and the negative half period is controlled to be switched off and switched on according to a PID regulation result, so that the bias magnetism of the transformer is suppressed. The method takes a DPS processor as a basis, the bias magnetism suppression is achieved basically achieved by control software, and the control is simple; the characteristics of a static error can be eliminated ingeniously by PID control, and a bias magnetism phenomenon of the transformer can be completely and theoretically eliminated; and meanwhile, the transformer has an overcurrent protection function.

Description

technical field [0001] The invention relates to a method for suppressing the magnetic bias of a transformer, in particular to a method for suppressing the magnetic bias of a transformer matched with a full-bridge inverter. Background technique [0002] The full-bridge conversion circuit topology is one of the most commonly used circuit topologies in DC / DC converters at home and abroad, and it is the preferred topology in medium and high-power applications; the full-bridge conversion circuit topology is shown in the attached figure 1 shown. [0003] A very thorny problem generally exists in this type of topology, that is, the bias phenomenon of the main transformer. The reasons for the DC bias are as follows: ①The saturation voltage drop of each tube of the two bridge arms in the inverter is different when they are turned on, and the turn-off time is inconsistent, which makes the positive and negative waveform amplitudes of the voltage applied to the primary side of the tran...

AI Technical Summary

Problems solved by technology

[0007] The present invention solves the problems of poor reliability or complicated hardware circuit structure in existing bias suppression methods, and provides a method for suppressing transformer bias that cooperates with a full-bridge inverter

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