A 0°~360° digital phase shift control method and system

Abstract

The invention discloses a 0-360 degree digital phase shift control method and system. A first reference wave and a second reference wave which are complementary to each other are generated, wherein the first reference wave and the second reference wave are same in duty cycle and frequency; one bridge arm of a phase controlled bridge circuit is selected and serves as a leading bridge arm, and the rest bridge arms serve as lagging bridge arms; a control signal of a switch pipe on the leading bridge arm is aligned with the first reference wave, the first reference wave or the second reference wave serves as an initial control signal of switch pipes on the lagging bridge arms, phase shifting is conducted on the initial control signal of lagging bridge arms, a control signal of all the switch pipes on the lagging bridge arms is generated, the lagging bridge arms are thus lagged by a set phase shift angle relative to the leading bridge arm, the phase shift range is 0-360 degrees, and therefore 0-360 degree digital phase shift is completed. According to the method and the system, very smooth switching can be achieved between a 180-degree point and a 360-degree point where problems are easy to occur, on the basis that phase shift at any angle can be very conveniently achieved, the duty cycle is changed at will, and generation of a dead zone is not affected.

Description

technical field [0001] The invention belongs to the technical field of power electronics, and in particular relates to a 0°-360° digital phase-shift control method and system. Background technique [0002] The traditional PWM control method achieves control by adjusting the pulse width. The switching method is hard switching. Due to the unavoidable parasitic parameters of the switching device and the devices connected to it, the voltage and current passing through the switching device are not pure square waves. Therefore, the power tube During the switching process, the voltage and current waveforms of the switching devices overlap, resulting in switching losses. And as the frequency increases, the proportion of switching loss in the total loss also increases proportionally. The phase-shift PWM control method realizes the change of the effective output pulse width by moving the phase-shift angle of the lagging bridge arm. The switching method is soft switching, which can be...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the problem that most of the current phase shift control algorithms can only realize phase shift within the range of 0°~180°, and the duty cycle cannot be adjusted arbitrarily, or it is difficult to realize the adjustment of the duty cycle, the present invention proposes a 0°~360° °Digital phase shift control method and system, which can achieve very smooth switching at the 180° point and 360° point where problems are prone to occur, and can also be very conveniently realized on the basis of phase shifting at any angle, arbitrarily changing the duty cycle, without affecting the generation of the dead zone

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