Flux weakening control method and flux weakening control device of motor and readable storage medium

Abstract

The invention provides a flux weakening control method of a motor, a flux weakening control device of the motor and a readable storage medium. The flux weakening control method of the motor comprisesthe steps of obtaining a direct-axis instruction voltage, a quadrature-axis instruction voltage and a bus voltage of the motor; based on the fact that the change rate of the bus voltage is larger thana first threshold value, adjusting the bus voltage, and calculating flux weakening current according to the bus voltage, the direct-axis instruction voltage and the quadrature-axis instruction voltage; and performing flux weakening control on the motor according to the flux weakening current. By means of the technical scheme, on one hand, the problem that when the bus voltage is too low, motor energy flows back to the driver, and consequently the voltage of the driver fluctuates violently and even overvoltage is out of control can be effectively solved; and on the other hand, the problem thatthe flux-weakening current is reduced due to bus voltage recoil can be avoided, the accuracy of the flux-weakening current is ensured, and the control effect on the motor is further improved.

Description

technical field [0001] The present invention relates to the technical field of motor control, in particular to a motor field weakening control method, a motor field weakening control device and a readable storage medium. Background technique [0002] Because electrolytic capacitors have problems such as life, reliability, and cost, film capacitors with small values ​​are used to replace large-value electrolytic capacitors, that is, the non-electrolytic capacitor control method is adopted. After adopting the electrolytic capacitor control method, the busbar voltage fluctuates twice the grid-side voltage frequency and even drops to near zero. The fluctuating busbar voltage requires field-weakening control even more, but even if the field-weakening control is adopted, there is still current control when the busbar voltage is too low Poor problem, under some working conditions, the motor energy may even be fed back to the driver, causing the bus voltage to backshoot, such as fi...

AI Technical Summary

Problems solved by technology

After adopting the electrolytic capacitor control method, the busbar voltage fluctuates twice the grid-side voltage frequency and even drops to near zero. The fluctuating busbar voltage requires field-weakening control even more, but even if the field-weakening control is adopted, there is still current control when the busbar voltage is too low Poor problem, under some working conditions, the motor energy may even be fed back to the driver, causing the bus voltage to backshoot, such as figure 1 As shown, the bus voltage has a backshoot phenomenon relative to the AC voltage

[0003] The field weakening control in the related technology will use the real-time bus voltage and its average value as the feedback voltage of the field weakening control. If the field weakening current is not enough, the bus voltage backlash will occur, and the backlashed bus voltage will increase the real-time bus voltage and its average value. , to further reduce the magnitude of the field-weakening current, aggravate the insufficient voltage, and cause the current runaway and further backlash of the bus voltage, and even cause a fault shutdown

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