Inverter driving signal modulation method and device, and computer readable storage medium

Abstract

The invention discloses an inverter driving signal modulation method, which comprises the following steps of in each half carrier period of a triangular carrier, acquiring a duty ratio of three-phase output of an inverter under the modulation of space vector pulse width modulation of a target voltage vector; obtaining a sector where the target voltage vector is located according to the phase angle of the target voltage vector; and adjusting the three-phase duty ratio of the target voltage vector according to the sector where the target voltage vector is located and the duty ratio of the three-phase output of the inverter, and modulating the target voltage vector after the duty ratio is adjusted by using triangular carrier waves to generate a driving signal of the inverter. According to the modulation method, space vector pulse width modulation is improved, the three-phase output duty ratio of the inverter is increased or decreased or subjected to phase shifting, a peak-to-peak value of common-mode voltage is reduced under the condition that the hardware cost is not increased, the service life of a motor bearing is prolonged, and moreover, under the low modulation ratio, the zero vector is reserved for synthesis of the target voltage vector, so the carrier frequency sub-harmonic in the phase current of the motor is relatively small, and operation noise is reduced.

Description

technical field [0001] The invention relates to the field of motor control, in particular to an inverter driving signal modulation method, equipment and computer-readable storage medium. Background technique [0002] In the field of electric vehicles, the driving motors are mostly three-phase permanent magnet synchronous motors and three-phase asynchronous motors, and are driven by three-phase two-level inverters. Such as Figure 1a with Figure 1b As shown, the three-phase two-level inverter has 8 possible switching states, corresponding to the 8 basic vectors SV of the d-q complex plane 0 ~SV 7 ,SV 0 and SV 7 is coincident at the origin, where, express Figure 1b The switch of the upper bridge arm of the middle inverter is in the off state, S 1 , S 3 , S 5 Indicates that the switch of the upper bridge arm of the inverter is in the closed state. Figure 1b Middle V dc is the bus voltage, in order to ensure the sinusoidal degree of the three-phase current of the ...

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Problems solved by technology

For this reason, the present invention proposes an inverter drive signal modulation method, which can solve the problem that the carrier frequency harmonics in the motor phase current increase significantly, resulting in a significant decrease in motor efficiency and sharp carrier frequency noise, without increasing hardware costs. question

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