Rotor-free sensor motor driver and vehicle having same

Abstract

The invention discloses a driver of a rotor-free sensor motor, which comprises a control circuit and a power driving circuit, and is characterized by having a three-phase phase-shift comparison circuit and a counter electromotive force zero crossing point detection circuit, wherein the counter electromotive force zero crossing point detection circuit comprises a phase-line voltage-division circuit, the output of the three-phase phase-shift comparison circuit is electrically connected with a single chip in the control circuit, and the counter electromotive force zero crossing point detection circuit is electrically connected with the single chip; when the motor runs at different rotation speeds and has different loads, the driver can change the phase correctly and is stable to start, thereby improving the electric efficiency of the motor; and the driver is applied to an electric vehicle, the electric vehicle is free from shaking after being started, and the driving miles of the vehicle can be improved.

Description

technical field [0001] The invention relates to the field of a brushless DC motor without a rotor sensor, and also relates to a vehicle equipped with the motor. Background technique [0002] In the existing rotorless sensor motor driver, the phase line of the motor is generally filtered, and the three-phase pulse generated by phase shifting is fed back to the microcontroller as a commutation signal. The phase shift angle of the commutation signal is related to the speed, motor load, and motor power. , so that the commutation angle of the motor is shifted. Once the shift of the commutation angle occurs, the output torque of the leading or lagging motor will decrease, and the input current of the power supply will increase, so the electrical efficiency will decrease. When this drive is used on an electric vehicle, the acceleration force is obviously insufficient, the maximum speed per hour is obviously reduced, and the continuation mileage is obviously shortened. [0003] The...

AI Technical Summary

Problems solved by technology

[0003] The existing rotorless sensor motor driver also adopts the back electromotive force detection of the motor phase line to determine the commutation time, but when the motor is started, it needs to do a stepping method to let the motor rotate first to generate a back electromotive force. The stepping method Whether it can start successfully depends on the load of the motor and the driving current in the stepping mode, and the vibration of the motor is particularly large. Due to the vibration of the motor, the back electromotive force generated is unstable and it is difficult to start successfully.

When using this driver on an electric vehicle, due to the heavy load and large fluctuations of the motor when starting, the vehicle will vibrate strongly when starting, and the riders have different styles, so it is difficult to control the smooth start of the vehicle

[0004] The existing motor driver without rotor sensor generally adopts the working method of two tubes conducting six beats, and the motor emits a large noise when commutating phases

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