A drive circuit for a three-phase brushless DC motor

Abstract

The invention discloses a drive circuit of a three-phase brushless direct-current motor. The drive circuit of the three-phase brushless direct-current motor comprises drive modules of three phases. The drive module of each phase comprises a voltage division unit, a stabilivolt, a first switch unit, a stabilized voltage supply, a wave shaping circuit, a second switch unit and a third switch unit, wherein a first end of the voltage division unit is connected with a first end of the first switch unit, the cathode of the stabilivolt is connected to a second end of the voltage division unit, the anode of the stabilivolt is connected to a third end of the voltage division unit, the input end of the stabilized voltage supply is connected to the second end of the voltage division unit, a first input end of the wave shaping circuit is connected to the positive electrode of the output end of the stabilized voltage supply, a second input end of the wave shaping circuit is connected to the third end of the voltage division unit, the grounding end of the wave shaping circuit is connected to the ground through a resistor, a first end of the second switch unit is connected to the positive electrode of the output end of the stabilized power supply, and a first end of the third switch unit is connected with a second end of the second switch unit to serve as the output end of the drive circuit. The working voltage of the drive circuit of the three-phase brushless direct-current motor can range from 28V to 90V, and the drive circuit of the three-phase brushless direct-current motor is simple and easy to implement.

Description

technical field [0001] The invention belongs to the field of three-phase brushless direct current motors, and more specifically relates to a driving circuit of a three-phase brushless direct current motor. Background technique [0002] For the existing three-phase brushless DC motor drive circuit, the working voltage range of the three-phase bridge circuit is usually 28V-36V. If the MOS tube of the upper bridge arm of the three-phase bridge needs to work for a long time, an independent isolation voltage must be added to it. The upper bridge arm drives the driving circuit of the MOS tube to supply power, so the circuit is complicated, there are many components, the volume is large, and the reliability is reduced. Most of them use the bootstrap capacitor power supply method, the capacity of their own capacitors is limited, and the charge and discharge need to work in the switch state, so it must work in the switch state, the MOS tube of the upper bridge is not suitable for lon...

AI Technical Summary

Problems solved by technology

[0004] In view of the above defects or improvement needs of the prior art, the present invention provides a drive circuit for a three-phase brushless DC motor, the purpose of which is to make the operating voltage range of the three-phase bridge circuit wide, thereby solving the problem of the existing three-phase bridge circuit The operating voltage range is narrow, and the motor cannot rotate at a low speed, resulting in technical problems that damage the drive circuit

Images