CN111817622A - A brushed motor long tail type H bridge drive circuit - Google Patents

Abstract

The invention discloses a brush motor long tail type H-bridge driving circuit, which comprises an H-shaped reversing bridge circuit, a field effect transistor grid driving power circuit, a long tail type PWM width modulation circuit and a high-voltage constant-current voltage-stabilizing power supply circuit, wherein the H-shaped reversing bridge circuit is connected with the field effect transistor grid driving power circuit; the field effect transistor grid driving power supply circuit provides a driving power supply for the H-shaped reversing bridge circuit, the long tail type PWM width modulation circuit is connected with the H-shaped reversing bridge circuit in series, and the high-voltage constant-current voltage-stabilizing power supply circuit supplies power for the long tail type PWM width modulation circuit; the invention simplifies the circuit design and also improves the overall reliability of the circuit essentially; the speed regulation with 100% duty ratio can be realized, only one path of PWM signals is needed for driving and speed regulation, and the condition that 'pipe explosion' occurs when the upper pipe and the lower pipe of the H bridge are simultaneously conducted due to the fact that a plurality of paths of PWM signal waves have problems due to phase positions and a time sequence generating circuit or software is completely avoided.

Description

A brushed motor long tail type H bridge drive circuit

technical field

The invention relates to a brushed motor drive circuit related to a railway passenger car, a locomotive wiper drive motor, a coupler motor, an automatic door motor, etc., in particular to a brushed motor long tail type H-bridge drive circuit, belonging to the technical field of motors and railway passenger cars. manufacturing technology.

Background technique

The railway passenger car manufacturing industry has developed by leaps and bounds in recent years. A large number of automation equipment is used in various functional units of the vehicle, among which the rotating motor is usually used as the actuator; at present, the commonly used motor forms of the vehicle include DC brushless motor and DC brush In addition to its own significant advantages, the brushless motor often relies on the driver and internal software, and its drive logic is relatively complex, which is prone to problems such as software runaway and hardware damage; and its low-speed performance and small starting torque problems The sensorless brushless motor is particularly prominent; because many devices on the vehicle, such as the wiper drive motor, the coupler motor, and the automatic door motor, have very large static resistance, which often lead to problems in starting the brushless motor when it is running. Therefore, the above important equipment The driving motors used are almost all brushed DC motors, and their excellent mechanical characteristics and simple and reliable driving and speed regulation methods can well meet the needs of railway vehicle operating conditions.

In the field of DC brush motor drive, when the application has speed regulation requirements, almost all use H-bridge drive circuits composed of MOSFET field effect transistors; the existing designs all use dedicated H-bridge drive chips or discrete components to drive, such as IR2110 and other dedicated drives The H-bridge driver chip, the upper tube driving depends on the bootstrap voltage established by the alternate conduction of the upper and lower tubes, to realize the driving of the upper tube; some special modules use the built-in charge pump to realize the upper tube driving. ; However, the built-in charge pump module must have a built-in H-bridge or half-arm H-bridge, and the maximum applicable voltage is low, which is far from meeting the requirements of the maximum voltage of DC145V for the drive motor of railway passenger car equipment; and the IR2110 bootstrap special chip, often At least two PWM signals or four PWM signals with a phase difference of 180 degrees are required, and a duty cycle of 2-5% must be set aside in each driving pulse period to drive the lower tube to conduct, so as to achieve Establish the bootstrap voltage required for driving the upper tube. In order to ensure that the upper and lower tubes will not be turned on at the same time in the process of driving the upper tube and the lower tube alternately, it is necessary to leave a certain width of dead zone on the upper and lower tube driving signals. The multi-channel PWM signal with complex phase and timing relationship leads to complicated design and debugging, which seriously reduces the reliability of the system, which is contrary to the tenet of railway passenger car equipment reliability first.

SUMMARY OF THE INVENTION

In order to solve the deficiencies of the prior art, the present invention provides a brushed motor long tail type H-bridge drive circuit, which simplifies the circuit design and improves the overall reliability of the circuit substantially; it can realize 100% duty cycle speed regulation. , and only one PWM signal for driving and speed regulation is required, which completely avoids the "exploded tube" caused by the simultaneous conduction of the upper and lower tubes of the H bridge when the multi-channel PWM signal wave has problems with the phase, timing generation circuit or software. situation occurs.

The technical scheme adopted in the present invention is:

A brushed motor long-tail H-bridge drive circuit, comprising an H-shaped commutation bridge circuit, a field effect transistor gate drive power circuit, a long-tail PWM width adjustment circuit and a high-voltage constant-current regulated power supply circuit; the The FET gate drive power circuit provides drive power for the H-shaped commutation bridge circuit, the long-tail PWM width adjustment circuit is connected in series with the H-shaped commutation bridge circuit, and the high-voltage constant-current regulated power supply circuit is Long tail type PWM width adjustment circuit power supply.

As a further preference of the present invention, the FET gate drive power circuit includes a motor reverse control isolated drive power circuit and a motor forward rotation control isolated drive power circuit; the motor reverse control isolated drive power circuit and the motor positive drive The switch control isolated drive power circuit provides the drive power for the H-shaped commutation bridge circuit together;

The motor reverse control isolated drive power circuit includes a power conversion circuit composed of an isolated switching power supply integrated circuit U1, a resistor R3, a resistor R4, a diode D4, a zener diode Z1 and a switching transformer T1, and the power conversion circuit will supply power. The power supply at the terminal is converted into two independent power supplies, one of which is rectified and filtered by the diode D1 and the capacitor C1, and the gate discharge circuit composed of the PNP transistor Q1, the diode D2 and the resistor R1 is output to the VG1+ terminal and the VG1- terminal; After another independent power supply is rectified and filtered by diode D3 and capacitor C2, the gate discharge circuit composed of PNP transistor Q2, diode D5 and resistor R2 is output to VG3+ terminal and VG3- terminal;

The motor forward rotation control isolated drive power circuit includes a power conversion circuit composed of an isolated switching power supply integrated circuit U2, a resistor R7, a resistor R8, a diode D8, a Zener diode Z2 and a switching transformer T2, and the power conversion circuit will supply power. The power supply at the terminal is converted into two independent power supplies. One of the independent power supplies is rectified and filtered by the diode D7 and the capacitor C3, and the gate discharge circuit composed of the PNP transistor Q3, the diode D6 and the resistor R5 is output to the VG2+ terminal and the VG2- terminal; After another independent power supply is rectified and filtered by diode D10 and capacitor C4, the gate discharge circuit composed of PNP transistor Q4, diode D9 and resistor R6 is output to VG4+ terminal and VG4- terminal.

As a further preference of the present invention, the H-shaped commutation bridge circuit includes a field effect transistor Q5, a field effect transistor Q6, a field effect transistor Q7, a field effect transistor Q8, a gate resistor R9, a gate resistor R10, a gate resistor R12, gate resistor R13, gate resistor R14, gate resistor R15, gate resistor R16 and gate resistor R17;

One end of the gate resistor R9 is connected to the gate of the field effect transistor Q6, and the other end is connected to the output terminal VG1+ of the gate drive power circuit of the field effect transistor; one end of the gate resistor R13 is connected to the gate of the field effect transistor Q6, and the other end is connected to the field The source of the FET Q6 and the output terminal VG1- of the FET gate drive power circuit; the drain of the FET Q6 is connected to the positive pole of the power supply of the motor; the source of the FET Q6 is connected to the drain of the FET Q7 and connected at the same time One end of the power supply end of the motor; one end of the gate resistor R14 is connected to the gate of the field effect transistor Q7, the other end is connected to the output terminal VG2+ of the gate drive power circuit of the field effect transistor, and one end of the gate resistor R16 is connected to the gate of the field effect transistor Q7 , the other end is connected to the source of the field effect transistor Q7 and the output terminal VG2- of the gate drive power circuit of the field effect transistor;

One end of the gate resistor R10 is connected to the gate of the field effect transistor Q5, and the other end is connected to the output terminal VG4+ of the gate drive power circuit of the field effect transistor; one end of the gate resistor R12 is connected to the gate of the field effect transistor Q5, and the other end is connected to the field The source of the FET Q5 and the output terminal VG4- of the FET gate drive power supply circuit; the drain of the FET Q5 is connected to the positive pole of the power supply of the motor; the source of the FET Q5 is connected to the drain of the FET Q8 and connected at the same time The other end of the power supply end of the motor; one end of the gate resistor R15 is connected to the gate of the field effect transistor Q8, the other end is connected to the output terminal VG3+ of the gate drive power circuit of the field effect transistor, and one end of the gate resistor R17 is connected to the gate of the field effect transistor Q8 pole, the other end is connected to the source of the field effect transistor Q8 and the output terminal VG3- of the gate drive power circuit of the field effect transistor;

The source electrode of the field effect transistor Q7 is connected to the source electrode of the field effect transistor Q8, and then the long tail PWM width adjustment circuit is connected.

As a further preference of the present invention, the long-tail PWM width adjustment circuit includes an overcurrent protection circuit.

As a further preference of the present invention, the long-tail PWM width adjustment circuit includes a driver chip U5, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a resistor R22, a resistor R23, a resistor R24, a field effect transistor Q9, a capacitor C6, Capacitor C7, capacitor C8, diode D12 and Zener diode Z4;

One end of the resistor R21 is connected to the 3-pin of the driver chip U5, the other end is connected to the 5-pin ground of the driver chip U5, one end of the resistor R24 is connected to the 1-pin of the driver chip U5, and the other end is connected to the 5-pin ground of the driver chip U5; the capacitor C7 and the resistor R24 is connected in parallel, one end of the resistor R18 is connected to pin 1 of the driver chip U5, the other end is connected to the power supply pin 8 of the driver chip U5, and the power supply pin 8 of the driver chip U5 is connected to the high-voltage constant-current regulated power supply circuit; capacitor C6 is connected in parallel with the driver chip Between pin 8 and pin 5 of U5; the pin 6 and pin 7 of the driver chip U5 are connected to the cathode of diode D12, and the anode of diode D12 is connected to the gate of field effect transistor Q9; resistor R19 is connected in parallel with diode D12, and the anode of Zener diode Z4 is connected to The source of the field effect transistor Q9, the negative electrode of the Zener diode Z4 is connected to the gate of the field effect transistor Q9, the resistor R20 is connected in parallel with the Zener diode Z4, one end of the resistor R23 is connected to the source of the field effect transistor Q9, and the other end is connected to the 5 of the driver chip U5. One end of the resistor R22 is connected to the source of the FET Q9, and the other end is connected to the 2 pin of the driver chip U5; one end of the capacitor C8 is connected to the 2 pin of the driver chip U5, and the other end is connected to the 5 foot ground of the driver chip U5; the FET Q7 The source electrode is connected to the source electrode of the field effect transistor Q8 and then the drain electrode of the field effect transistor Q9 is connected.

As a further preference of the present invention, the high-voltage constant-current regulated power supply circuit includes a diode D11, a constant-current tube U3, a resistor R11, a capacitor C5 and a zener diode Z3;

The positive pole of the diode D11 is connected to the positive pole of the power supply of the motor, and the negative pole is connected to the 1 pin of the constant current tube U3; the 2 pin of the constant current tube U3 is connected to the negative pole of the Zener diode Z3, and one end of the resistor R11 is connected to the 3 pin of the constant current tube U3, and the other end Connect the negative pole of the Zener diode Z3; the capacitor C5 is connected in parallel with the Zener diode Z3; the negative pole of the Zener diode Z3 is connected to the power supply terminal 8 of the driver chip U5, and the positive pole of the Zener diode Z3 is grounded.

The beneficial effect of the present invention is that only one general-purpose driving chip is used, which is far less than the problem of requiring two or four general-purpose or special-purpose driving integrated circuits for ordinary H-bridges, which not only simplifies the circuit design, but also substantially improves the overall circuit performance. Reliability; at the same time, due to the reduction of the number of chips, a simple high-voltage constant current circuit can be used to directly take power from the power supply of the motor, which makes the driving and isolation of the chip simple, and the four in the H-shaped commutation bridge circuit The field effect transistor is only responsible for the commutation work of the motor. The fixed gate driving voltage can make the field effect transistor fully conductive. The fixed gate driving voltage makes the field effect transistor work in a fully conductive state without switching loss. Greatly reduces the heat generation of the field effect tube; at the same time, it avoids the possibility of simultaneous conduction of the upper and lower tubes during switching, and avoids the occurrence of the tube explosion phenomenon; the present invention adopts a field effect tube and a commonly used general-purpose single-pole low-side field effect tube. The drive integrated circuit forms a typical PWM width adjustment circuit, which only needs one PWM control signal, which saves the resources of controlling the single-chip microcomputer, simplifies the control sequence and logic, and does not have the problem of setting the dead time of the upper and lower tubes to turn on and control the PWM signal at the same time. The reliability of the system reaches the theoretical maximum value in the design of the PWM control motor speed. The duty cycle of the PWM control signal can be from 0 to 100%, which ensures that the motor can run at full speed within the rated power supply voltage range of the vehicle; achieve 100% Duty cycle speed regulation, and only one PWM signal for driving and speed regulation is required, which completely avoids the simultaneous conduction of the upper and lower tubes of the H bridge due to problems with the phase, timing generation circuit or software of multiple PWM signal waves. A "bursting" situation occurs.

Description of drawings

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

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

As shown in Figure 1: This embodiment is a brushed motor long tail type H bridge drive circuit, including an H-shaped commutation bridge circuit, a field effect transistor gate drive power supply circuit, a long tail type PWM width adjustment circuit and a high voltage Constant current voltage regulator power supply circuit; FET gate drive power supply circuit provides driving power for H-shaped commutation bridge circuit, long tail PWM width adjustment circuit is connected in series with H-shaped commutation bridge circuit, high voltage constant current voltage regulation The power supply circuit supplies power for the long tail type PWM width adjustment circuit.

In this embodiment, the FET gate drive power circuit includes a motor reverse rotation control isolated drive power circuit and a motor forward rotation control isolated drive power circuit; the motor reverse control isolated drive power circuit and the motor forward rotation control isolated drive power circuit The driving power circuit jointly provides the driving power for the H-shaped commutation bridge circuit;

The motor reverse control isolated drive power circuit includes a power conversion circuit composed of an isolated switching power supply integrated circuit U1, a resistor R3, a resistor R4, a diode D4, a Zener diode Z1 and a switching transformer T1. The power conversion circuit converts the power supply at the power supply end. It is converted into two independent power supplies, one of which is rectified and filtered by diode D1 and capacitor C1, and the gate discharge circuit composed of PNP transistor Q1, diode D2 and resistor R1 is output to VG1+ and VG1- terminals; the other one After the independent power supply is rectified and filtered by the diode D3 and the capacitor C2, the gate discharge circuit composed of the PNP transistor Q2, the diode D5 and the resistor R2 is output to the VG3+ terminal and the VG3- terminal; it is used to drive the H-shaped commutation bridge circuit. Corresponding to the FET, when the 1 pin of the isolated switching power supply integrated circuit U1 is at a high level, the power supply starts to output; when the 1 pin of the isolated switching power supply integrated circuit U1 is at a low level, the power supply stops outputting.

The motor forward rotation control isolated drive power circuit includes a power conversion circuit composed of an isolated switching power supply integrated circuit U2, a resistor R7, a resistor R8, a diode D8, a Zener diode Z2 and a switching transformer T2. The power conversion circuit converts the power supply at the power supply end It is converted into two independent power supplies, one of which is rectified and filtered by diode D7 and capacitor C3, and the gate discharge circuit composed of PNP transistor Q3, diode D6 and resistor R5 is output to VG2+ and VG2- terminals; the other one After the independent power supply is rectified and filtered by the diode D10 and the capacitor C4, the gate discharge circuit composed of the PNP transistor Q4, the diode D9 and the resistor R6 is output to the VG4+ terminal and the VG4- terminal; it is used to drive the H-shaped commutation bridge circuit. Corresponding to the FET, when the 1 pin of the isolated switching power supply integrated circuit U2 is at a high level, the power supply starts to output; when the 1 pin of the isolated switching power supply integrated circuit U2 is at a low level, the power supply stops outputting.

In this embodiment, the H-shaped commutation bridge circuit includes a field effect transistor Q5, a field effect transistor Q6, a field effect transistor Q7, a field effect transistor Q8, a gate resistor R9, a gate resistor R10, a gate resistor R12, a gate resistor, and a gate resistor R9. Resistor R13, gate resistor R14, gate resistor R15, gate resistor R16 and gate resistor R17;

One end of the gate resistor R9 is connected to the gate of the field effect transistor Q6, and the other end is connected to the output terminal VG1+ of the FET gate drive power circuit; one end of the gate resistor R13 is connected to the gate of the field effect transistor Q6, and the other end is connected to the source of the field effect transistor Q6 pole and the output terminal VG1- of the gate drive power supply circuit of the FET; the drain of the FET Q6 is connected to the positive pole of the power supply of the motor, in this embodiment, the power supply of the motor is 110V; the source of the FET Q6 is connected to the FET The drain of Q7 is connected to one end of the power supply end of the motor at the same time; one end of the gate resistor R14 is connected to the gate of the field effect transistor Q7, the other end is connected to the output terminal VG2+ of the gate drive power circuit of the field effect transistor, and one end of the gate resistor R16 is connected to the field effect transistor. The gate of Q7, the other end is connected to the source of the field effect transistor Q7 and the output terminal VG2- of the gate drive power circuit of the field effect transistor;

One end of the gate resistor R10 is connected to the gate of the field effect transistor Q5, and the other end is connected to the output terminal VG4+ of the gate drive power circuit of the field effect transistor; one end of the gate resistor R12 is connected to the gate of the field effect transistor Q5, and the other end is connected to the source of the field effect transistor Q5 pole and the output terminal VG4- of the gate drive power supply circuit of the field effect transistor; the drain electrode of the field effect transistor Q5 is connected to the positive pole of the power supply of the motor, in this embodiment, the power supply of the motor is 110V; The drain of Q8 is connected to the other end of the power supply end of the motor at the same time; one end of the gate resistor R15 is connected to the gate of the field effect transistor Q8, the other end is connected to the output end VG3+ of the gate drive power circuit of the field effect transistor, and one end of the gate resistor R17 is connected to the field effect The gate of the transistor Q8, the other end is connected to the source of the field effect transistor Q8 and the output terminal VG3- of the gate drive power circuit of the field effect transistor;

The source electrode of the field effect transistor Q7 is connected to the source electrode of the field effect transistor Q8, and then the long tail PWM width adjustment circuit is connected.

In this embodiment, the long-tail PWM width adjustment circuit includes an overcurrent protection circuit; the long-tail PWM width adjustment circuit includes a driver chip U5, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a resistor R22, a resistor R23, and a resistor R24 , FET Q9, capacitor C6, capacitor C7, capacitor C8, diode D12 and Zener diode Z4;

One end of the resistor R21 is connected to the 3 pin of the driver chip U5, the other end is connected to the 5 pin ground of the driver chip U5, one end of the resistor R24 is connected to the 1 pin of the driver chip U5, and the other end is connected to the 5 pin ground of the driver chip U5; the capacitor C7 is connected in parallel with the resistor R24 , One end of resistor R18 is connected to pin 1 of driver chip U5, the other end is connected to pin 8 of power supply terminal of driver chip U5, and pin 8 of power supply terminal of driver chip U5 is connected to the high-voltage constant-current regulated power supply circuit; capacitor C6 is connected in parallel with the power supply terminal of driver chip U5 Between pin 8 and pin 5; the pin 6 and pin 7 of the driver chip U5 are connected to the cathode of diode D12, the anode of diode D12 is connected to the gate of field effect transistor Q9; resistor R19 is connected in parallel with diode D12, and the anode of Zener diode Z4 is connected to the field effect The source of the transistor Q9, the negative electrode of the Zener diode Z4 is connected to the gate of the FET Q9, the resistor R20 is connected in parallel with the Zener diode Z4, one end of the resistor R23 is connected to the source of the FET Q9, and the other end is connected to the ground of pin 5 of the driver chip U5 ; One end of resistor R22 is connected to the source of field effect transistor Q9, and the other end is connected to pin 2 of driver chip U5; one end of capacitor C8 is connected to pin 2 of driver chip U5, and the other end is connected to ground of pin 5 of driver chip U5; the source electrode of field effect transistor Q7 It is connected to the source of the field effect transistor Q8 and then the drain of the field effect transistor Q9.

In this embodiment, the high-voltage constant-current regulated power supply circuit includes a diode D11, a constant-current tube U3, a resistor R11, a capacitor C5 and a zener diode Z3;

The positive pole of the diode D11 is connected to the positive pole of the power supply of the motor, and the negative pole is connected to the 1 pin of the constant current tube U3; the 2 pin of the constant current tube U3 is connected to the negative pole of the Zener diode Z3, one end of the resistor R11 is connected to the 3 pin of the constant current tube U3, and the other end is connected steadily The negative electrode of the voltage diode Z3; the capacitor C5 is connected in parallel with the Zener diode Z3; the negative electrode of the Zener diode Z3 is connected to the power supply terminal 8 of the driving chip U5, and the positive electrode of the Zener diode Z3 is grounded.

In this embodiment, the isolated switching power supply integrated circuits U1 and U2 use the isolated switching power supply integrated circuit LT8300 which can be enabled through programmable control, the constant current tube U3 uses SM2082GA, and the driver chip U5 uses the EG3002 chip with conventional overcurrent protection.

The circuit principle of this embodiment is as follows:

When the 1-pin FWD of the isolated switching power supply integrated circuit U1 is high level "1", VG1+ and VG1-, VG3+ and VG3- output DC12V voltage respectively, the voltage between VG1+ and VG1- is applied to the field effect transistor through resistor R9 Between the gate and the source of Q6, the FET Q6 is turned on, the voltage between VG3+ and VG3- is applied between the gate and the source of the FET Q8 through the resistor R15, and the FET Q8 is turned on; when When the duty cycle of the 3-pin PWM control signal of the driver chip U5 is greater than or equal to 1%, the field effect transistor Q9 is turned on and the motor is reversed.

When the 1-pin REV of the isolated switching power supply integrated circuit U2 is high level "1", VG2+ and VG2-, VG4+ and VG4- output DC12V voltage respectively, the voltage between VG2+ and VG2- is applied to the field effect transistor through resistor R14 Between the gate and the source of Q7, the field effect transistor Q7 is turned on, the voltage between VG4+ and VG4- is applied between the gate and the source of the field effect transistor Q5 through the resistor R10, and the field effect transistor Q5 is turned on; when When the duty cycle of the 3-pin PWM control signal of the driver chip U5 is greater than or equal to 1%, the field effect transistor Q9 is turned on and the motor rotates forward.

When the duty cycle of the PWM control signal of pin 3 of the driver chip U5 is equal to 0, that is, when the pin 3 of the driver chip U5 is at a low level "0", the field effect transistor Q9 is turned off; at this time, when the isolated switching power supply integrated circuit U1 When the 1-pin FWD of the isolated switching power supply integrated circuit U2 is high-level "1" and the 1-pin REV of the isolated switching power supply integrated circuit U2 is also high-level "1", the motor performs energy consumption braking; when the isolated switching power supply integrated circuit U1's 1 When the pin FWD is low level "0" and the 1 pin REV of the isolated switching power supply integrated circuit U2 is also low level "0", the motor stops.

The present invention adopts a common field effect transistor driving chip U5, because the energy consumption of one control chip is very low, the power is directly taken from the main power supply of the H-shaped commutation bridge circuit through the diode D11 and the constant current tube U3, and the DC12V voltage is obtained as the driving force The chip U5 is powered; it greatly simplifies the power supply circuit design of the switch circuit.

In this embodiment, the field effect transistor Q9 is connected to the lower end of the H-shaped commutation bridge circuit; in practical application, the field effect transistor Q9 can also be connected to the upper end of the H-shaped commutation bridge circuit, and its principle still belongs to the invention. The category of tail-type H-bridge driver circuit.

The present invention only uses one general-purpose driver chip, which is far less than the problem of requiring two or four general-purpose or special-purpose driver integrated circuits for ordinary H-bridges, which not only simplifies the circuit design, but also substantially improves the overall reliability of the circuit; at the same time, Due to the reduction of the number of chips and the low power consumption, a simple high-voltage constant current circuit can be used to directly obtain power from the power supply of the motor, which makes the driving and isolation of the chips simple.

The three-way drive signal logic of the present invention is simple, and the control unit and the drive unit can be electrically isolated by a simple optocoupler isolation circuit; the drive chip U5 is a general chip with a protection shutdown function. During the implementation process, any manufacturer and The single-channel low-side driver chip of the model can be competent as long as it has the shutdown protection function, and there are no strict requirements; the circuit of the present invention can work in a wide voltage range, and is theoretically not affected by any parameters of the control circuit, avoiding The conventional bootstrap boost H-bridge drive circuit does not require special adjustment, as long as the five FETs can withstand the withstand voltage, the circuit can work normally.

In this embodiment, a long-tail PWM width adjustment circuit and an H-shaped commutation bridge circuit are connected in series to form a long-tail structure drive circuit. Compared with the prior art, the four field effect transistors in the H-shaped commutation bridge circuit are It is only responsible for the commutation work of the motor. The fixed gate driving voltage can make the FET fully conduct. The fixed gate driving voltage makes the FET work in a fully conducting state without switching loss, which greatly reduces the field effect. The effect tube heats up; at the same time, it avoids the possibility of simultaneous conduction of the upper and lower tubes during switching, and avoids the occurrence of tube explosion.

The invention adopts a field effect transistor and a commonly used general unipolar low-side field effect transistor drive integrated circuit to form a typical PWM width adjustment circuit, only needs one PWM control signal, saves the resources of controlling the single-chip microcomputer, and simplifies the control sequence and logic , there is no problem that the upper and lower tubes are turned on at the same time and control the PWM signal to set the dead time, so that the reliability of the system can reach the theoretical maximum value in the design of the PWM control motor speed, and the duty cycle of the PWM control signal can be from 0 to 100%. It is ensured that the motor can run at full speed within the rated power supply voltage range of the vehicle.

The invention adopts the low-side driving integrated circuit of the general field effect transistor, which simplifies the overcurrent protection circuit, and the protection value can be set arbitrarily; it solves the problem that the traditional H-bridge driving circuit adopts the measurement of the D-S voltage of the lower tube of the H-bridge for protection and cannot accurately set the protection. The problem of current; through the control circuit, during the commutation of the H-bridge, turn off the field effect transistor Q9 in the long-tail PWM width adjustment circuit to ensure zero impact when the FETs of the H-bridge arm are commutated; after the commutation is completed, wait for After the corresponding FET is fully turned on, the PWM control signal gradually turns on the FET Q9 in the long-tail PWM widening circuit, which effectively improves the reliability of the circuit and avoids the conventional H-bridge being susceptible to commutation shock during commutation. The disadvantage of damage; it has the function of supporting energy consumption braking. It only needs to apply a simple logic control signal to realize energy consumption braking, and when braking, the field effect transistor Q9 is turned off, and any operation for braking is performed. It will not cause damage to the H-shaped commutation bridge circuit and the field effect transistor Q9.

The above are only the preferred embodiments of the patent of the present invention. It should be pointed out that for those skilled in the art, without departing from the principle of the patent of the present invention, several improvements and modifications can also be made. These improvements and Retouching should also be regarded as the protection scope of the patent of the present invention.

Claims (6)

1. The utility model provides a there is brush motor long tail formula H bridge drive circuit which characterized in that: the high-voltage constant-current voltage-stabilizing power supply circuit comprises an H-shaped reversing bridge circuit, a field-effect tube grid driving power supply circuit, a long-tail PWM width modulation circuit and a high-voltage constant-current voltage-stabilizing power supply circuit; the field-effect tube grid driving power supply circuit provides a driving power supply for the H-shaped reversing bridge circuit, the long tail type PWM width-adjusting circuit is connected with the H-shaped reversing bridge circuit in series, and the high-voltage constant-current voltage-stabilizing power supply circuit supplies power for the long tail type PWM width-adjusting circuit.

2. The brush motor long tail H-bridge drive circuit according to claim 1, wherein the fet gate drive power supply circuit comprises a motor reverse rotation control isolated drive power supply circuit and a motor forward rotation control isolated drive power supply circuit; the motor reverse rotation control isolated driving power circuit and the motor forward rotation control isolated driving power circuit jointly provide driving power for the H-shaped reversing bridge circuit;

the motor reverse rotation control isolation type driving power supply circuit comprises a power supply conversion circuit consisting of an isolation type switch power supply integrated circuit U1, a resistor R3, a resistor R4, a diode D4, a voltage stabilizing diode Z1 and a switch transformer T1, wherein the power supply conversion circuit converts a power supply at a power supply end into two independent power supplies, and after one independent power supply is rectified and filtered by a diode D1 and a capacitor C1, a grid discharge circuit consisting of a PNP triode Q1, a diode D2 and a resistor R1 outputs to a VG1+ end and a VG 1-end; the other path of independent power supply is rectified and filtered by a diode D3 and a capacitor C2, and then a grid discharge circuit consisting of a PNP triode Q2, a diode D5 and a resistor R2 outputs to a VG3+ end and a VG 3-end;

the motor forward rotation control isolation type driving power supply circuit comprises a power supply conversion circuit consisting of an isolation type switch power supply integrated circuit U2, a resistor R7, a resistor R8, a diode D8, a voltage stabilizing diode Z2 and a switch transformer T2, wherein the power supply conversion circuit converts a power supply at a power supply end into two independent power supplies, and a grid discharge circuit consisting of a PNP triode Q3, a diode D6 and a resistor R5 outputs to a VG2+ end and a VG 2-end after one independent power supply is rectified and filtered by a diode D7 and a capacitor C3; and the other path of independent power supply is rectified and filtered by a diode D10 and a capacitor C4, and then the grid discharge circuit consisting of a PNP triode Q4, a diode D9 and a resistor R6 outputs to a VG4+ end and a VG 4-end.

3. The brush motor long tail type H-bridge driving circuit according to claim 2, wherein the H-shaped commutation bridge circuit comprises a field effect transistor Q5, a field effect transistor Q6, a field effect transistor Q7, a field effect transistor Q8, a gate resistor R9, a gate resistor R10, a gate resistor R12, a gate resistor R13, a gate resistor R14, a gate resistor R15, a gate resistor R16 and a gate resistor R17;

one end of the grid resistor R9 is connected with the grid of the field effect transistor Q6, and the other end is connected with the output end VG1+ of the grid driving power supply circuit of the field effect transistor; one end of the grid resistor R13 is connected with the grid of a field effect transistor Q6, and the other end is connected with the source of the field effect transistor Q6 and the output end VG 1-of the field effect transistor grid driving power circuit; the drain electrode of the field effect tube Q6 is connected with the anode of a power supply of the motor; the source electrode of the field effect transistor Q6 is connected with the drain electrode of the field effect transistor Q7 and is simultaneously connected with one end of the power supply end of the motor; one end of the grid resistor R14 is connected with the grid of the field effect transistor Q7, the other end is connected with the output end VG2+ of the grid drive power circuit of the field effect transistor, one end of the grid resistor R16 is connected with the grid of the field effect transistor Q7, and the other end is connected with the source of the field effect transistor Q7 and the output end VG 2-of the grid drive power circuit of the field effect transistor;

one end of the grid resistor R10 is connected with the grid of the field effect transistor Q5, and the other end is connected with the output end VG4+ of the grid driving power supply circuit of the field effect transistor; one end of the grid resistor R12 is connected with the grid of a field effect transistor Q5, and the other end is connected with the source of the field effect transistor Q5 and the output end VG 4-of the field effect transistor grid driving power circuit; the drain electrode of the field effect tube Q5 is connected with the anode of a power supply of the motor; the source electrode of the field effect transistor Q5 is connected with the drain electrode of the field effect transistor Q8 and is simultaneously connected with the other end of the power supply end of the motor; one end of the grid resistor R15 is connected with the grid of the field effect transistor Q8, the other end is connected with the output end VG3+ of the grid drive power circuit of the field effect transistor, one end of the grid resistor R17 is connected with the grid of the field effect transistor Q8, and the other end is connected with the source of the field effect transistor Q8 and the output end VG 3-of the grid drive power circuit of the field effect transistor;

and the source electrode of the field effect transistor Q7 is connected with the source electrode of the field effect transistor Q8 and then connected with a long tail type PWM width modulation circuit.

4. The brush motor long tail H-bridge drive circuit according to claim 1 or 3, wherein the long tail PWM width modulation circuit comprises an overcurrent protection circuit.

5. The brush motor long tail type H bridge drive circuit according to claim 4, wherein the long tail type PWM width modulation circuit comprises a drive chip U5, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a resistor R22, a resistor R23, a resistor R24, a field effect transistor Q9, a capacitor C6, a capacitor C7, a capacitor C8, a diode D12 and a zener diode Z4;

one end of the resistor R21 is connected with the pin 3 of the driving chip U5, the other end of the resistor R24 is connected with the pin 5 ground of the driving chip U5, one end of the resistor R24 is connected with the pin 1 of the driving chip U5, and the other end of the resistor R3578 is connected with the pin 5 ground of the driving chip U5; the capacitor C7 is connected in parallel with the resistor R24, one end of the resistor R18 is connected with pin 1 of the driving chip U5, the other end is connected with pin 8 of the power supply end of the driving chip U5, and pin 8 of the power supply end of the driving chip U5 is connected with a high-voltage constant-current voltage-stabilizing power supply circuit; the capacitor C6 is connected in parallel between the pin 8 and the pin 5 of the driving chip U5; the 6 pin and the 7 pin of the driving chip U5 are connected and then connected with the cathode of the diode D12, and the anode of the diode D12 is connected with the grid of the field effect transistor Q9; the resistor R19 is connected with the diode D12 in parallel, the anode of the voltage-stabilizing diode Z4 is connected with the source electrode of the field-effect tube Q9, the cathode of the voltage-stabilizing diode Z4 is connected with the grid electrode of the field-effect tube Q9, the resistor R20 is connected with the voltage-stabilizing diode Z4 in parallel, one end of the resistor R23 is connected with the source electrode of the field-effect tube Q9, and the other end of the resistor R23 is connected with the 5-pin ground of; one end of the resistor R22 is connected with the source electrode of the field effect transistor Q9, and the other end is connected with the 2 feet of the driving chip U5; one end of the capacitor C8 is connected with the 2 pin of the driving chip U5, and the other end is connected with the 5 pin ground of the driving chip U5; the source electrode of the field effect transistor Q7 is connected with the source electrode of the field effect transistor Q8 and then connected with the drain electrode of the field effect transistor Q9.

6. The brush motor long tail type H-bridge driving circuit according to claim 5, wherein the high voltage constant current voltage stabilization power supply circuit comprises a diode D11, a constant current tube U3, a resistor R11, a capacitor C5 and a voltage stabilization diode Z3;

the anode of the diode D11 is connected with the anode of a power supply of the motor, and the cathode of the diode D11 is connected with the pin 1 of the constant current tube U3; a pin 2 of the constant current tube U3 is connected with the cathode of the voltage stabilizing diode Z3, one end of the resistor R11 is connected with a pin 3 of the constant current tube U3, and the other end is connected with the cathode of the voltage stabilizing diode Z3; the capacitor C5 is connected with the Zener diode Z3 in parallel; the cathode of the voltage-stabilizing diode Z3 is connected with the power supply end pin 8 of the driving chip U5, and the anode of the voltage-stabilizing diode Z3 is grounded.

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