Processing method and device of motor under locked-rotor state

Abstract

The embodiment of the invention discloses a processing method and device of a motor under a locked-rotor state, and belongs to the field of driving and control of an electric vehicle. A torque input to a vector controller is regulated to a target torque when that the motor is in the locked-rotor state is determined according to a current rotational speed and a command torque, the target torque is in a way that torque change quantity is superposed on the basis of the command torque, the torque change quantity is a torque oscillating in a preset period and changing in a positive-negative alternative way, the target torque is send to the vector controller, a three-phase pulse width modulation (PWM) duty ratio is obtained by calculation of the vector controller according to the target torque and then is sent to a power component, and the power component controls the motor to rotate. According to the method disclosed by the embodiment of the invention, the target torque is in a way that the torque change quantity is superposed on the basis of the command torque, the torque change quantity is the torque oscillating in the preset period and changing in the positive-negative alternative way, so that a rotational angle of a motor rotor changes periodically, a current peak of a single phase of the power component can be correspondingly reduced, and the motor can be prevented from being damaged when in the locked-rotor state due to excessive high temperature rising.

Description

technical field [0001] The invention relates to the field of drive control of electric vehicles, in particular to a processing method and device in a locked-rotor state of a motor. Background technique [0002] At present, people pay more and more attention to the protection of the environment and the effective and reasonable use of energy. Therefore, electric vehicles with high efficiency, energy saving and environmental protection have become one of the development trends of the automobile industry. During the use of electric vehicles, motor stalls often occur due to various reasons. For example, when electric vehicles pass through potholes at low speeds, the wheels often sink, causing the motors to stall. Among them, the rotation of the motor is controlled by the drive system of the electric vehicle. [0003] Such as figure 1 As shown, it shows a schematic diagram of a driving system of an electric vehicle in the prior art. The drive system includes a vector controlle...

AI Technical Summary

Problems solved by technology

[0006] When the motor is in a locked-rotor state, the method of reducing the switching frequency of the power element can reduce the loss of the power element to a certain extent, but it cannot fundamentally change the problem of excessive single-phase current flowing through the power element in the locked-rotor state.

Therefore, this method is not effective in preventing damage to power components caused by excessive temperature rise caused by excessive current.

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