System and method for deadbeat control of permanent magnet synchronous motor based on complex vector modeling in discrete domain

Abstract

The invention discloses a permanent magnet synchronous motor deadbeat control system and method based on discrete domain complex vector modeling, which is characterized in that it includes a permanent magnet synchronous motor, an encoder, an abc-dq coordinate conversion unit, and a speed outer loop PI control controller, current deadbeat controller, dq‑αβ coordinate conversion unit, SVPWM modulation module, inverter. The beneficial effects achieved by the present invention: in the modeling process of the current prediction model, the inverter and the motor are regarded as an integral model, and the delay effect of the inverter is considered, and the built model is more accurate than the traditional current prediction model ;The current error integral compensation module is added to the deadbeat controller, which greatly improves the static error of the stator current control, and finally realizes the goal of good control of the deadbeat control at low switching frequency. The results show that the motor speed and The stator current control is good, the static difference of the motor stator current control is small, and the output torque ripple has also been improved.

Description

technical field [0001] The invention relates to a permanent magnet synchronous motor deadbeat control system and method based on discrete domain complex vector modeling, and belongs to the technical field of motor control. Background technique [0002] Permanent magnet synchronous traction motors for rail transit generally have a large power of hundreds of kilowatts. Due to the limitation of switching losses, in reality, an inverter with a low switching frequency of about 500 Hz has to be used to control the drive motor. [0003] At present, permanent magnet synchronous motors generally use dual-PI vector control strategies, but at low switching frequencies, the system sampling delay will be greatly increased, which will destroy the dynamic decoupling in the vector control system, and the motor control is difficult to meet the control requirements, and the output stator The current contains a large number of harmonics, which makes the output torque of the motor fluctuate gre...

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Problems solved by technology

[0006] In order to solve the deficiencies in the prior art, the object of the present invention is to provide a permanent magnet synchronous motor deadbeat control system and method based on discrete domain complex vector modeling, which solves the problem of traditional permanent magnet synchronous motor deadbeat control systems at low switching frequencies. There are problems such as poor control effect, large current static difference, and large output torque pulsation. The deadbeat control strategy has a good control effect at low switching frequency, and the current control static difference is also small.

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