Repelling drive circuit for H bridge of motor

Abstract

The invention relates to a repelling drive circuit for an H bridge of a motor. The repelling drive circuit comprises drive circuits which are connected with four bridge arms of an H bridge circuit respectively, wherein each bridge arm drive circuit comprises an isolating photocoupler for carrying out photoelectric isolation, and a repelling photocoupler for carrying out repelling on the bridge arm drive circuits at the same side of the H bridge; the repelling photocouplers on the same bridge arm are connected with primary sides of the isolating photocouplers in series; and secondary sides of the repelling photocouplers are connected with the primary sides of the isolating photocouplers on different bridge arms at the same side, so that the repelling photocouplers are simultaneously conducted when signals of the isolating photocouplers at the same side of the H bridge are controlled to be simultaneously effective. The secondary sides of the repelling photocouplers are connected with the primary sides of the isolating photocouplers on different bridge arms at the same side and the signals form a passage through the secondary sides of the repelling photocouplers, so that the isolating photocouplers are cut off; and switch tubes of the upper bridge arm and the lower bridge arm at the same side of the H bridge are free of a drive signal to achieve the target of drive repelling of the motor.

Description

technical field [0001] The invention relates to the technical field of motor drive, in particular to a mutually exclusive drive circuit of a motor H bridge. Background technique [0002] When driving a motor, an H-bridge circuit composed of four MOS tubes or power transistors is usually used. If the switch tubes of the upper and lower arms of the motor H-bridge circuit on the same side are turned on at the same time, it is equivalent to a short circuit from the power supply to the ground, and it is likely Cause damage to the triode or MOS tube on the bridge arm of the H bridge, or even burn out the power supply, so it is necessary to ensure that the bridge arms on the same side of the H bridge are not turned on at the same time. [0003] A Chinese utility model patent with the authorized publication number CN 204517703 U discloses a DC motor H-bridge driving circuit. The H-bridge circuit includes two sets of upper and lower bridge arms, that is, the upper and lower bridge ar...

AI Technical Summary

Problems solved by technology

[0004] The H-bridge driving circuit can be used to connect with the H-bridge circuit and control the forward and reverse rotation of the motor by driving the H-bridge circuit, but there is no mutual exclusion circuit designed to prevent the simultaneous conduction of the upper and lower bridge arms on the same side of the H-bridge , so when some misoperation or other reasons make the control signals of the upper and lower bridge arms on the same side of the H-bridge circuit valid at the same time, it will cause the switches of the upper and lower bridge arms on the same side to be turned on at the same time, so that the connection from the power supply to the ground is A short circuit is formed, which damages the H-bridge switch tube and even burns out the power supply

Images