阅读说明：本技术 一种h桥电机驱动电路 (H-bridge motor driving circuit ) 是由 项乐宏 刘树 任云涛 于 2020-07-24 设计创作，主要内容包括：本发明公开一种H桥电机驱动电路,包括控制器、H桥驱动电路电机、第一泄放电阻和第二泄放电阻,H桥驱动电路通过共模电感连接电机,共模电感种第一电感的第二端以及第二电感的第二端连接电机；控制器的控制端与H桥驱动电路中的下桥的第二开关模块和第四开关模块连接,用于控制第二开关模块和第四开关模块的通断。电机转动时产生的反向电动势,能够通过压敏电阻以及泄放电阻进行泄放；电机停止时,产生的电动势很大,配合控制器控制,输出的PWM控制信号控制开关管Q2以及Q4导通,将电机上的反向电动势进行泄放,保护其他元件；本发明通过调节电容,改变PWM脉冲上升沿的时间,配合共模电感以及抑制电容,能够抑制辐射的干扰,顺利通过EMC测试。(The invention discloses an H-bridge motor driving circuit which comprises a controller, an H-bridge driving circuit motor, a first bleeder resistor and a second bleeder resistor, wherein the H-bridge driving circuit is connected with the motor through a common-mode inductor, and the second end of the common-mode inductor, namely a first inductor, and the second end of a second inductor are connected with the motor; and the control end of the controller is connected with the second switch module and the fourth switch module of the lower bridge in the H-bridge drive circuit and is used for controlling the on-off of the second switch module and the fourth switch module. The reverse electromotive force generated when the motor rotates can be released through the piezoresistor and the release resistor; when the motor stops, the generated electromotive force is large, and the PWM control signal is output to control the switching tubes Q2 and Q4 to be conducted in cooperation with the control of the controller, so that the reverse electromotive force on the motor is released, and other elements are protected; according to the invention, through adjusting the capacitor, the time of the rising edge of the PWM pulse is changed, and the common-mode inductor and the suppression capacitor are matched, so that the interference of radiation can be suppressed, and the EMC test can be successfully passed.)

1. A H-bridge motor driving circuit comprises a controller, an H-bridge driving circuit and a motor, wherein the H-bridge driving circuit is connected with the motor through a common-mode inductor, a first end of a first inductor in the common-mode inductor is connected with a joint of a first switch module and a second switch module in the H-bridge driving circuit, and a first end of a second inductor in the common-mode inductor is connected with a joint of a third switch module and a fourth switch module in the H-bridge driving circuit; the second end of the first inductor and the second end of the second inductor are connected with the motor,

the method is characterized in that: the first inductor is connected with the first end of the first inductor, and the other end of the first inductor is grounded; one end of the second bleeder resistor is connected with the first end of the second inductor, and the other end of the second bleeder resistor is grounded;

and the control end of the controller is connected with the second switch module and the fourth switch module of the lower bridge in the H-bridge drive circuit and is used for controlling the on-off of the second switch module and the fourth switch module.

2. The H-bridge motor drive circuit of claim 1, wherein: and a suppression capacitor is connected between the first end of the first inductor and the first end of the second inductor in the common mode inductor.

3. The H-bridge motor drive circuit of claim 1, wherein: the PWM pulse on-off circuit further comprises a regulating capacitor connected to the switch module and used for changing the rising edge time of the PWM pulse generated by the controller so as to control the on-off of the switch module.

4. The H-bridge motor drive circuit of claim 3, wherein: and the adjusting capacitor is connected with an adjusting resistor in parallel.

5. The H-bridge motor drive circuit of claim 1, wherein: the first switch module, the second switch module, the third switch module and the fourth switch module are all connected with the controller through diodes.

6. The H-bridge motor drive circuit of claim 5, wherein: the diode is connected with a connecting resistor in parallel.

7. The H-bridge motor drive circuit of claim 1, wherein: the motor is connected with a piezoresistor in parallel.

Technical Field

The invention belongs to the field of motor driving, and particularly relates to an H-bridge motor driving circuit.

Background

Traditional H bridge motor drive circuit's motor is when operation in-process or stop, no matter be with higher speed or when slowing down the condition, the electric current that flows through the motor can change, then can produce induced-current, so according to lenz's law, the motor then can produce reverse electromotive force, the reverse electromotive force of production can produce the impact to the switch tube among the H bridge motor drive circuit, if reverse electromotive force is too high, then can damage the switch tube, H bridge motor drive circuit can't carry out normal work, consequently, it is very important to obtain an H bridge motor drive circuit that can overcome above-mentioned defect.

Disclosure of Invention

In order to solve the technical problem, the invention provides an H-bridge motor driving circuit, which comprises a controller, an H-bridge driving circuit and a motor, wherein the H-bridge driving circuit is connected with the motor through a common-mode inductor, wherein a first end of a first inductor in the common-mode inductor is connected with a joint of a first switch module and a second switch module in the H-bridge driving circuit, and a first end of a second inductor in the common-mode inductor is connected with a joint of a third switch module and a fourth switch module in the H-bridge driving circuit; the common-mode inductor is connected with a second end of the first inductor and a second end of the second inductor, and further comprises a first bleeder resistor and a second bleeder resistor, wherein one end of the first bleeder resistor is connected with the first end of the first inductor, and the other end of the first bleeder resistor is grounded; one end of the second bleeder resistor is connected with the first end of the second inductor, and the other end of the second bleeder resistor is grounded; and the control end of the controller is connected with the second switch module and the fourth switch module of the lower bridge in the H-bridge drive circuit and is used for controlling the on-off of the second switch module and the fourth switch module.

A suppression capacitor is connected between the first end of the first inductor and the first end of the second inductor in the common-mode inductor LF1, and the suppression capacitor can suppress radiation interference, so that the invention can smoothly pass EMC tests.

The PWM pulse on-off control circuit further comprises an adjusting capacitor connected to the switch module, and the adjusting capacitor is connected with an adjusting resistor in parallel and used for changing the rising edge time of the PWM pulse generated by the controller so as to control the on-off of the switch module.

The first switch module, the second switch module, the third switch module and the fourth switch module are all connected with the controller through diodes, the diodes are connected with connecting resistors in parallel, the connecting resistors are connected with the diodes in parallel, the turn-off speed can be increased under the condition that the turn-on speed is not influenced, the loss of the switch modules is reduced, and the efficiency is improved.

The motor is connected with the piezoresistor in parallel, and the resonance energy generated by the motor can be eliminated or controlled within a certain range.

Compared with the prior art, the invention has the advantages that: the reverse electromotive force generated when the motor rotates can be released through the piezoresistor and the release resistor; when the motor stops, the generated electromotive force is large, and the PWM control signal is output to control the switching tubes Q2 and Q4 to be conducted in cooperation with the control of the controller, so that the reverse electromotive force on the motor is released, and other elements are protected; according to the invention, through adjusting the capacitor, the time of the rising edge of the PWM pulse is changed, and the common-mode inductor and the suppression capacitor are matched, so that the interference of radiation can be suppressed, and the EMC test can be successfully passed.

Drawings

FIG. 1 is a circuit diagram of the present invention;

Detailed Description

In order that those skilled in the art will better understand the invention and thus more clearly define the scope of the invention as claimed, it is described in detail below with respect to certain specific embodiments thereof. It should be noted that the following is only a few embodiments of the present invention, and the specific direct description of the related structures is only for the convenience of understanding the present invention, and the specific features do not of course directly limit the scope of the present invention.

Referring to the drawings, the present invention adopts the following technical solution that an H-bridge motor driving circuit includes a controller, an H-bridge driving circuit and a motor M1, where the H-bridge driving circuit includes a first switch module, a second switch module, a third switch module and a fourth switch module, and in this embodiment, the switch module is a MOS transistor, but is not limited to the MOS transistor.

The H-bridge driving circuit comprises an MOS tube Q1, an MOS tube Q2, an MOS tube Q3 and an MOS tube Q4, wherein the drains of the MOS tube Q1 and the MOS tube Q3 are connected with a power supply voltage VCC, the source of the MOS tube Q1 is connected with the drain of the MOS tube Q2, the source of the MOS tube Q3 is connected with the drain of the MOS tube Q4, and the joint of the MOS tube Q1 and the MOS tube Q2 is connected with the first end of a first inductor L1 in the common-mode inductor LF 1; the connection between the MOS transistor Q3 and the MOS transistor Q4 is connected to the first end of the second inductor L2 in the common mode inductor LF1, the gates of the MOS transistor Q1, the MOS transistor Q2, the MOS transistor Q3, and the MOS transistor Q4 are respectively connected to the control end of the controller, and the sources of the MOS transistor Q2 and the MOS transistor Q4 are grounded.

A second end of a first inductor L1 in the common mode inductor LF1 is connected with the motor M1, and a first end of the first inductor L1 is connected with a source electrode of the MOS transistor Q1; the second end of the second inductor L2 in the common mode inductor LF1 is connected to the motor M1, and the first end of the second inductor L2 is connected to the source of the MOS transistor Q3.

When the MOS transistor Q1 and the MOS transistor Q4 are turned on, current flows through the motor M1 from left to right, so that the motor M1 is driven to rotate clockwise; when the controller controls the MOS transistor Q2 and the MOS transistor Q3 to be switched on, the current M1 flows through the motor M1 from right to left, thereby driving the motor M1 to rotate counterclockwise.

The inductor further comprises a first bleeder resistor R9 and a second bleeder resistor R10, wherein one end of the first bleeder resistor R9 is connected with the first end of the first inductor L1, and the other end of the first bleeder resistor R3526 is grounded; one end of the second bleeder resistor R10 is connected to the first end of the second inductor L2, and the other end is grounded.

The control end of the controller is respectively connected with the gates of the MOS transistor Q2 and the MOS transistor Q4, and is used for controlling the on/off of the MOS transistor Q2 and the MOS transistor Q4, when the current is released, the MOS transistor Q2 and the MOS transistor Q4 are controlled by the controller to be conducted, a current loop is generated due to the back electromotive force, the current generated by the back electromotive force is grounded through the loop, and as shown in fig. 1, the direction of a dotted arrow is the generated current loop.

A suppression capacitor Y2 is connected between the first end of the first inductor L1 and the first end of the second inductor L2 in the common mode inductor LF1, and the suppression capacitor Y2 can suppress radiation interference, so that the invention can smoothly pass an EMC test.

The circuit also comprises an adjusting capacitor connected to the switch module, the adjusting capacitor is connected with an adjusting resistor in parallel, the adjusting capacitor comprises a first adjusting capacitor C1, a second adjusting capacitor C2, a third adjusting capacitor C3 and a fourth adjusting capacitor C4, and the adjusting resistor comprises a third resistor R3, a fourth resistor R4, a seventh resistor R7 and an eighth resistor R8. The first adjusting capacitor C1 is connected with the grid and the source of the MOS transistor Q1, and the third resistor R3 is connected with the first adjusting capacitor C1 in parallel; the second adjusting capacitor C2 is connected with the grid and the source of the MOS transistor Q2, and the fourth resistor R4 is connected with the second adjusting capacitor C2 in parallel; the third adjusting capacitor C3 is connected with the grid and the source of the MOS transistor Q3, and the seventh resistor R7 is connected with the third adjusting capacitor C3 in parallel; the fourth adjusting capacitor C4 is connected in parallel with the source and the gate of the MOS transistor Q4, and the eighth resistor R8 is connected in parallel with the fourth capacitor C4. The adjusting capacitor and the adjusting resistor are used for changing the rising edge time of the PWM pulse generated by the controller so as to control the on-off of the switch module.

The gate of the MOS transistor Q1 is connected to the output terminal of the controller through a first resistor R1, and the first resistor R1 is connected in parallel with a first diode D1; the gate of the MOS transistor Q2 is connected to the output terminal of the controller through a second resistor R2, and a second diode D2 is connected in parallel to the second resistor R2; the gate of the MOS transistor Q3 is connected to the output terminal of the controller through a third resistor R3, and the third resistor R3 is connected in parallel with a third diode D3; the gate of the MOS transistor Q4 is connected to the output terminal of the controller through a fourth resistor R4, and a fourth diode D4 is connected in parallel to the fourth resistor R4; the parallel diode of the connecting resistor can increase the turn-off speed under the condition of not influencing the turn-on speed, reduce the loss of the MOS tube and improve the efficiency.

And a piezoresistor RV1 is connected between the third end and the fourth end of the common-mode inductor, namely, a piezoresistor RV1 is installed at two ends of the motor M1 and passes through the common-mode inductor LF1, the piezoresistor RV1 and the common-mode inductor LF1 are combined together to eliminate the resonance energy which is generated by the motor M1 in the operation and influences the EMC, and the resonance energy generated by the motor M1 can be eliminated or controlled within a certain range by selecting the piezoresistor RV1 and the common-mode inductor LF1 with proper sizes.

Compared with the prior art, the invention has the advantages that: the back electromotive force generated when the motor M1 rotates can be discharged through the piezoresistor RV1 and the discharge resistor; when the motor M1 stops, the generated electromotive force is large, and the PWM control signal is controlled by matching with the controller to control the MOS tube Q2 and the MOS tube Q4 to be conducted, so that the reverse electromotive force on the motor M1 is released, and other elements are protected; according to the invention, through adjusting the capacitor, the rising edge time of the PWM pulse is changed, and the common-mode inductor LF1 and the suppression capacitor Y2 are matched, so that the radiated interference can be suppressed, and the EMC test can be successfully passed.

The above description is not intended to limit the present invention, and the present invention is not limited to the above examples, and variations, modifications, additions and substitutions which may be made by those skilled in the art within the spirit of the present invention are within the scope of the present invention.