Three-level pulse width modulation method and related equipment

Abstract

The invention discloses a magnetic levitation coil control system and a three-level pulse width modulation method and device thereof, a controller and a computer readable storage medium, and the three-level pulse width modulation method is applied to a half-bridge topology circuit and comprises the steps: determining an equivalent output duty ratio corresponding to an average output voltage set value; determining an output duration reference parameter; determining a corresponding target duty ratio and a target phase shift angle based on the equivalent output duty ratio and the output durationreference parameter; outputting a first control signal of which the duty ratio is the target duty ratio to the control end of a first switching tube in the half-bridge topological circuit; outputtinga second control signal of which the duty ratio is the target duty ratio to the control end of a second switching tube in the half-bridge topological circuit, wherein the phase delay angle of the second control signal relative to the first control signal is the target phase shift angle. According to the invention, based on the cooperative dynamic modulation of the duty ratio and the phase shift angle, the current ripple can be effectively reduced and the current bandwidth can be increased.

Description

technical field [0001] The present application relates to the technical field of electric control, in particular to a magnetic levitation coil control system and its three-level pulse width modulation method, device, controller and computer-readable storage medium. Background technique [0002] Magnetic levitation control is to use the principle that the magnetic field generates suction when passing through the surface of different media, and indirectly control the magnitude of the magnetic field suction by controlling the current of the magnetic levitation coil, so that the controlled object is suspended in a fixed position. Generally, the magnetic suspension bearing usually adopts the current differential control method of the upper and lower coils to realize the electromagnetic force control in the positive and negative directions. Therefore, for a single magnetic suspension coil, there is no need to change the current direction, and only need to realize unipolar current c...

AI Technical Summary

Problems solved by technology

However, most of the traditional three-level modulation methods use a modulation method with a fixed phase difference and a dynamically changing duty cycle, which makes the current ripple of the magnetic levitation coil larger and the current bandwidth smaller.

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