Motor locked-rotor current detection circuit

Abstract

The invention discloses a motor locked-rotor current detection circuit, which comprises a single chip microcomputer and a motor M, wherein a locked-rotor current detection circuit is arranged between the single chip microcomputer and the motor; the single chip microcomputer controls positive and reverse rotation of the motor through the locked-rotor current detection circuit; the motor M comprises a positive electrode of the motor and a negative electrode of the motor; the single chip microcomputer comprises I / O ports A, B and C; and the locked-rotor current detection circuit comprises current-limiting resistors R1 and R2, triodes Q1 and Q2, current-limiting diodes D1 and D2, relays K1 and K2 and sampling resistors R3 and R4. Through the designed scheme, the motor locked-rotor can be accurately detected and a power supply of the motor is timely powered off, so that the condition that the motor is damaged due to over-high locked-rotor current of the motor is avoided. By the motor locked-rotor current detection circuit, the detection accuracy rate is high, the cost is low, the structure is simple and the service lifetime of the motor is effectively prolonged.

Description

technical field [0001] The invention belongs to the technical field of detection circuits, and relates to a motor stall current detection circuit. Background technique [0002] Motor stalling is the phenomenon that the motor cannot start or stop rotating due to excessive motor load, dragging mechanical failure, bearing damage and sweeping. The power factor is extremely low when the motor is locked, and the value of the current (called the locked rotor current) is very large when the motor is locked, and the motor will be burned out if it takes a long time. [0003] When the motor rotates, the rotating magnetic field formed by the stator windings drives the rotor to rotate, and the magnetic field generated by the induced current in the rotor also induces a counter electromotive force in the stator windings, which is what we call inductive reactance, which prevents the motor from increasing the stator current. . If the motor is blocked, the above-mentioned counter electromot...

AI Technical Summary

Problems solved by technology

According to the size of the motor capacity and different processing techniques, the motor stall current is generally 12-50 times the rated current of the motor, which will not only easily cause damage to the motor, but also cause damage to electrical appliances, personal injury, and even fire

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