阅读说明：本技术 一种直流有刷电机驱动器 (Direct current brush motor driver ) 是由 陆健 于 2019-10-16 设计创作，主要内容包括：本发明公开了一种直流有刷电机驱动器,包括：P型MOS管、N型MOS管、P型MOS管控制电路、N型MOS管控制电路、正/反转控制电路、PWM控制电路、保护电路、电源接口、电机接口、控制接口,为减少电机启动时的电流,还设有NTC热敏电阻,可以有效延长电机换向碳刷的寿命。本发明可以支持频率18kHz以上的PWM,可以有效地降低电机噪音,并且能支持100%占空比的PWM。本发明MOS管的控制电路采用简单可靠的三极管、电阻、二极管和电容,不仅成本低,而且可靠性高,适合大规模推广使用。(The invention discloses a direct current brush motor driver, which comprises: the motor comprises a P-type MOS tube, an N-type MOS tube, a P-type MOS tube control circuit, an N-type MOS tube control circuit, a forward/reverse rotation control circuit, a PWM control circuit, a protection circuit, a power interface, a motor interface and a control interface, and is further provided with an NTC thermistor for reducing the current when the motor is started, so that the service life of a reversing carbon brush of the motor can be effectively prolonged. The invention can support PWM with frequency above 18kHz, can effectively reduce the noise of the motor, and can support PWM with 100% duty ratio. The control circuit of the MOS tube adopts simple and reliable triodes, resistors, diodes and capacitors, has low cost and high reliability, and is suitable for large-scale popularization and use.)

1. A DC brushed motor drive, comprising: p-type MOS tube, N-type MOS tube, P-type MOS tube control circuit, N-type MOS tube control circuit, forward/reverse control circuit, PWM control circuit, protection circuit, power interface, motor interface, and control interface, the P-type MOS tube control circuit mainly comprises a PNP triode, a resistor and a voltage stabilizing diode, the N-type MOS tube control circuit mainly comprises an NPN triode, a resistor and a voltage stabilizing diode, the forward/reverse rotation control circuit mainly comprises a resistor, a Schottky diode and a capacitor, the PWM control circuit mainly comprises a PNP triode, a resistor and a capacitor, the protection circuit mainly comprises a fuse, a Schottky diode, a TVS diode and a capacitor, two groups of circuits mainly connected by the P-type MOS tube and the N-type MOS tube form an H-bridge circuit, a motor interface is connected with the middle of the upper arm and the lower arm of the H-bridge circuit, and the control interface is connected with the forward/reverse rotation control circuit and the PWM control circuit.

2. The direct current brushed motor driver as defined in claim 1, wherein: and the NTC thermistor is connected between the P-type MOS tube and the N-type MOS tube in series.

3. A dc brushed motor driver according to claim 1 or 2, wherein: the motor interface is provided with a positive/negative rotation LED indicating lamp circuit.

4. A dc brushed motor driver according to claim 1 or 2, wherein: the schottky diode may be replaced with a fast recovery diode, an ultrafast recovery diode, or a rectifier diode.

5. A dc brushed motor driver according to claim 1 or 2, wherein: the fuse of the protection circuit is a PTC self-recovery fuse.

6. A dc brushed motor driver according to claim 1 or 2, wherein: the fuse of the protection circuit is a quick-break fuse.

7. A dc brushed motor driver according to claim 1 or 2, wherein: and the forward/reverse rotation control circuit and the PWM control circuit are provided with optical coupling isolation circuits.

Technical Field

The invention relates to the technical field of motor control, in particular to a direct-current brush motor driver.

Background

Direct current motors are widely used in the fields of daily life and industry. The dc motor can be classified into a brush motor and a brushless motor according to different commutation methods. The commutation of the brushless motor is realized by electronic control, which has the advantages of high reliability, no commutation spark, low mechanical noise, etc., but the control circuit is complex, the cost is high, and the brushless motor is generally used in occasions with higher requirements. The brush motor is commutated by the carbon brush, and has the advantages of quick start, timely braking, smooth speed regulation in a large range, relatively simple control circuit and low cost. Most of existing direct current brush motor drivers can meet the requirements of motor speed regulation and positive and negative rotation control, but few drivers are low in cost, and the problems that direct current brush motors are high in rotation noise and short in service life of carbon brushes can be well solved.

Disclosure of Invention

The invention aims to solve the defects of the prior art and provides a direct-current brush motor driver. The NTC thermistor is added in the motor driver circuit, so that the defect of large starting current of the direct current brush motor can be well overcome, and the service life of the motor reversing carbon brush can be prolonged. The invention can support PWM with frequency above 18kHz, can effectively reduce the noise of the motor, and can support PWM with 100% duty ratio. The control circuit of the MOS tube adopts simple and reliable triodes, resistors, diodes and capacitors, has low cost and high reliability, and is suitable for large-scale popularization and use.

In order to achieve the purpose, the invention provides the following technical scheme:

a direct current brushed motor drive comprising: p-type MOS tube, N-type MOS tube, P-type MOS tube control circuit, N-type MOS tube control circuit, forward/reverse control circuit, PWM control circuit, protection circuit, power interface, motor interface, and control interface, the P-type MOS tube control circuit mainly comprises a PNP triode, a resistor and a voltage stabilizing diode, the N-type MOS tube control circuit mainly comprises an NPN triode, a resistor and a voltage stabilizing diode, the forward/reverse rotation control circuit mainly comprises a resistor, a Schottky diode and a capacitor, the PWM control circuit mainly comprises a PNP triode, a resistor and a capacitor, the protection circuit mainly comprises a fuse, a Schottky diode, a TVS diode and a capacitor, two groups of circuits mainly connected by the P-type MOS tube and the N-type MOS tube form an H-bridge circuit, a motor interface is connected with the middle of the upper arm and the lower arm of the H-bridge circuit, and the control interface is connected with the forward/reverse rotation control circuit and the PWM control circuit.

As a further scheme of the invention: and the NTC thermistor is connected between the P-type MOS tube and the N-type MOS tube in series. The NTC thermistor is a resistor with resistance value decreasing with temperature increase, and the resistance value of the thermistor is generally 5-10 ohms at normal temperature. The resistance of a motor coil is low at the moment of starting the motor and no reverse electromotive force exists, so that the current is often very high, and the current at the moment of starting the motor can be effectively reduced due to the serial connection of the NTC thermistor in the circuit. After the motor is started, the temperature of the NTC thermistor can rise along with the time, the resistance value can be reduced to be very low, and the normal operation of the motor is hardly influenced.

As a further scheme of the invention: the motor interface is provided with a positive/negative rotation LED indicating lamp circuit.

As a further scheme of the invention: the schottky diode may be replaced with a fast recovery diode, an ultrafast recovery diode, or a rectifier diode.

As a further scheme of the invention: the fuse of the protection circuit is a PTC self-recovery fuse.

As a further scheme of the invention: the fuse of the protection circuit is a quick-break fuse.

As a further scheme of the invention: and the forward/reverse rotation control circuit and the PWM control circuit are provided with optical coupling isolation circuits.

Drawings

FIG. 1 is a schematic diagram of a left half of an H-bridge circuit according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of a forward/reverse control circuit according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of a PWM control circuit according to an embodiment of the present invention.

Fig. 4 is a schematic diagram of a power supply and protection circuit according to an embodiment of the invention.

FIG. 5 is a schematic diagram of a forward/reverse LED indicator light circuit according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

The invention provides a direct current brush motor driver, comprising: p-type MOS tube, N-type MOS tube, P-type MOS tube control circuit, N-type MOS tube control circuit, forward/reverse control circuit, PWM control circuit, protection circuit, power interface, motor interface, and control interface, the P-type MOS tube control circuit mainly comprises a PNP triode, a resistor and a voltage stabilizing diode, the N-type MOS tube control circuit mainly comprises an NPN triode, a resistor and a voltage stabilizing diode, the forward/reverse rotation control circuit mainly comprises a resistor, a Schottky diode and a capacitor, the PWM control circuit mainly comprises a PNP triode, a resistor and a capacitor, the protection circuit mainly comprises a fuse, a Schottky diode, a TVS diode and a capacitor, two groups of circuits mainly connected by the P-type MOS tube and the N-type MOS tube form an H-bridge circuit, a motor interface is connected with the middle of the upper arm and the lower arm of the H-bridge circuit, and the control interface is connected with the forward/reverse rotation control circuit and the PWM control circuit. See fig. 1, 2, 3 and 4. T1 is a P-type MOS tube, T2 is an N-type MOS tube, D1, D2 and D6 are zener diodes, D4, D5 and D8 are Schottky diodes, D7 is a TVS diode, Q1, Q2 and Q5 are PNP triodes, Q3 and Q4 are NPN triodes, R2-R14 are metal film resistors, C1, C2 and C3 are ceramic chip capacitors, and C4 is an electrolytic capacitor. Fig. 1 shows the left half of the H-bridge circuit, and the right half of the H-bridge circuit is mirror-symmetrical to the left half, so the right half of the H-bridge circuit is omitted in the drawings of the specification.

As a preferable scheme of the invention: and the NTC thermistor is connected between the P-type MOS tube and the N-type MOS tube in series. The resistor R1 of fig. 1 is an NTC thermistor.

As a preferable scheme of the invention: the motor interface is provided with a positive/negative rotation LED indicating lamp circuit. Referring to fig. 5, D9 and D10 are LED lights.

As a preferable scheme of the invention: the fuse of the protection circuit is a PTC self-recovery fuse. The fuse F1 of fig. 4 is a PTC self-healing fuse.

The control interface of the embodiment of the invention has 3 ports, namely a PWM signal port, a forward rotation signal port and a reverse rotation signal port. When the motor is required to rotate forwards, the forward rotation signal port and the PWM signal port are grounded, and when the motor is required to rotate backwards, the reverse rotation signal port and the PWM signal port are grounded. If the motor speed is controlled, the duty ratio of the PWM signal port can be controlled, and the higher the low-level duty ratio of the PWM signal port is, the higher the motor speed is. If the motor is in a braking state, the motor can be realized by grounding the forward signal port and the reverse signal port to be low level.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications, combinations, or alterations may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.