Motor driving circuit for underground water distributor

Abstract

The utility model relates to a motor drive circuit for an underground water distributor. Comprising a driving circuit which is provided with a pin connected with a main power supply, a pin connected with a power supply circuit for outputting a first power supply, a pin connected with a brushless motor for driving the brushless motor to operate, and a pin connected with a control circuit for feeding back a state signal to the control circuit and receiving an operation signal transmitted by the control circuit; the power supply circuit is connected to a pin, for outputting the first power supply, of the driving chip to output a second power supply; the control circuit comprises a control chip, and the control chip is provided with a pin connected with a second power supply and a pin connected with the driving circuit and used for outputting an operation signal to the driving chip and collecting a state signal; and adjusting the output operation signal according to the collected state signal. According to the utility model, the driving control of the brushless motor is realized without a software control algorithm and a rotation speed feedback-free sensor circuit, and the stability and the reliability of the motor of the underground water distributor are improved.

Description

Technical Field

[0001] The disclosed embodiments relate to the field of electric power technology, and in particular to a motor drive circuit for a downhole water distributor. Background Art

[0002] The underground intelligent water distributor is an important oil production and production increase instrument, and plays an important role in the exploration and development of the oil industry. As the core component of the instrument, the water nozzle assembly is driven by a motor, and finally completes the intelligent adjustment of the water nozzle opening size through a series of mechanical mechanisms. Therefore, a simple and reliable motor drive circuit is very critical to the entire instrument. At present, most similar instruments use a bridge drive circuit built with discrete components, which mainly drives brushed motors. Since discrete components such as resistors and capacitors are sensitive to temperature, and the underground environment is a harsh environment of high temperature and high pressure, and the life of the brushed motor is limited by the brushes, the long-term stability and reliability are poor.

[0003] Therefore, it is necessary to improve one or more problems existing in the above-mentioned related technical solutions.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Utility Model Content

[0005] The purpose of the embodiments of the present disclosure is to provide a motor drive circuit for a downhole water distributor, thereby at least solving one or more problems existing in the above-mentioned related technical solutions.

[0006] The purpose of the utility model is achieved by the following technical solutions:

[0007] The utility model provides a motor drive circuit for an underground water distributor, comprising:

[0008] A drive circuit, the drive circuit comprising a drive chip, the drive chip is provided with a pin connected to a main power supply, a pin connected to a power supply circuit and outputting a first power supply matching the power supply circuit, a pin connected to a brushless motor and driving the brushless motor to operate, and a pin connected to a control circuit and used to feed back a status signal to the control circuit and receive an operation signal transmitted by the control circuit;

[0009] A power supply circuit, the power supply circuit is connected to the pin of the driving chip outputting the first power supply, is provided with an operational amplifier for stepping down the first power supply, and outputs a second power supply matching the control circuit;

[0010] A control circuit, the control circuit includes a control chip, the control chip is provided with a pin connected to the second power supply, is provided with a pin connected to the drive circuit and is used to output the operation signal to the drive chip and collect the status signal; the control chip adjusts the output operation signal according to the collected status signal.

[0011] Optionally, the operation signal includes: a steering control signal, a brake signal and an enable signal; the status signal includes a speed feedback signal and a fault signal.

[0012] Optionally, the driving circuit includes a potentiometer, two ends of the potentiometer are connected to the second power supply and ground, and a center tap of the potentiometer is connected to a pin of the driving chip for configuring the rotation speed of the brushless motor.

[0013] Optionally, the driving chip uses an integrated circuit chip MCT8316A1TRGFR, and the total power supply is 24VDC.

[0014] Optionally, the drive chip is connected to the center tap of the potentiometer via the SPEED pin, the brake signal is input via the BREAK pin, the steering control signal is input via the DIR pin, the enable signal is input via the DRVOFF pin, the speed feedback signal is output via the FG pin, and the fault signal is output via the FAULT pin.

[0015] Optionally, the driver chip configures the minimum duty cycle of pulse width modulation by a resistor connected to the CONFIG_3 pin.

[0016] Optionally, the driver chip configures the first power supply through a resistor connected to a SLEW_RATE pin.

[0017] Optionally, the first power supply is 5VDC, and the power supply circuit uses an LDO chip to convert the first power supply into the second power supply.

[0018] Optionally, the control chip is an MCU chip, and the second power supply is 3.3 VDC.

[0019] Optionally, the control chip outputs the brake signal through the RC4 pin, outputs the steering control signal through the RC3 pin, outputs the enable signal through the RC6 pin, collects the speed feedback signal through the RC5 / CCP pin, and collects the fault signal through the RC1 pin.

[0020] The technical solution provided by the embodiments of the present disclosure may include the following beneficial effects:

[0021] In the embodiments of the present disclosure, the connection between the control chip and the drive chip enables the drive control of the brushless motor to be achieved without a software control algorithm and a speed feedback sensor circuit, thereby improving the working stability and reliability of the motor of the downhole water distributor.

[0022] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and are used together with the specification to explain the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 A schematic diagram showing the structure of a motor drive circuit for a downhole water distributor in an exemplary embodiment of the present disclosure is shown;

[0025] Figure 2 A schematic diagram showing the structure of a driving circuit in an exemplary embodiment of the present disclosure;

[0026] Figure 3 A schematic diagram showing the structure of a power supply circuit in an exemplary embodiment of the present disclosure;

[0027] Figure 4 A schematic diagram showing the structure of a control circuit in an exemplary embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0028] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that the disclosure will be more comprehensive and complete and to fully convey the concepts of the example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0029] In addition, the accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and their repeated description will be omitted. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and / or processor devices and / or microcontroller devices.

[0030] In this exemplary embodiment, a motor driving circuit for a downhole water distributor is first provided. Figure 1 As shown in , it includes: a driving circuit, a power supply circuit and a control circuit.

[0031] The driving circuit includes a driving chip U1, which is provided with a pin connected to the main power supply, a pin connected to the power supply circuit and outputs a first power supply matching the power supply circuit, a pin connected to the brushless motor and drives the brushless motor to operate, and a pin connected to the control circuit and used to feed back a state signal to the control circuit and receive an operation signal transmitted by the control circuit. The power supply circuit is connected to the pin outputting the first power supply of the driving chip U1, is provided with an operational amplifier for stepping down the first power supply, and outputs a second power supply matching the control circuit. The control circuit includes a control chip U3, which is provided with a pin connected to the second power supply, a pin connected to the driving circuit and used to output an operation signal and collect a state signal to the driving chip U1; the control chip U3 adjusts the output operation signal according to the collected state signal.

[0032] It should be understood that the input power of the entire circuit is a 24VDC power supply, which is directly provided to the motor driver chip to drive the motor. At the same time, the Buck regulator inside the motor driver chip outputs 5VDC to the power supply circuit; the power supply circuit converts 5VDC into 3.3VDC through the LDO chip and supplies it to the main control circuit; the main control circuit outputs forward and reverse, brake and stop signals to the motor driver circuit to control the normal operation of the motor, and receives the speed and fault signals output by the motor driver chip to determine the operating status of the motor.

[0033] It is also necessary to understand that, during specific operation, the brushless motor M1 runs at a corresponding speed according to the size of the SPEED speed control signal. During the operation of the motor, the relevant modules inside the driver chip U1 complete the zero-crossing detection and current detection of the three phases A, B, and C, and automatically adjust the pulse width modulation (PWM) signal that drives the built-in H-bridge circuit, and outputs the actual speed signal to the FG pin to feed back to the control chip U3. The control chip U3 can determine the actual operating position of the mechanical motion device, and control the operation and stop of the motor, as well as the rotation direction according to the position, thereby completing the control of the opening size of the water spout of the intelligent water distributor.

[0034] It is also important to understand that the MCT8316A1TRGFR chip integrates three 1 / 2H bridge circuits, a Buck power regulator, current detection, overvoltage and overcurrent protection, and optional closed-loop control. The maximum output current can reach 8A, and all control parameters can be configured through external resistors.

[0035] It is also necessary to understand that the driver chip U1 configures the motor running lead angle to 0° and the back EMF threshold to 200 by connecting R2 to the LDANGLE pin. The zero-crossing detection blanking time is configured to 6us, the PWM frequency is 50KHz, and the initial position detection algorithm frequency is 2KHz by connecting R3 to the CONFIG_1 pin. The overcurrent protection threshold is configured to 15A by connecting R4 to the CONFIG_2 pin, and the overcurrent protection mode is reset after 500ms. The cycle-by-cycle current limit is configured to 4.67A, the current sensing amplifier gain is 0.15V / A, and the open-loop current limit is 3.33A by connecting R7 to the ILIMIT pin. The alignment time is configured to 750ms by connecting R9 to the RMP_2 pin, dynamic demagnetization is disabled, the slow first cycle frequency is 0.5Hz, and the closed-loop acceleration is 75V / s. The motor starting mode is configured to be bilateral alignment by connecting R10 to the RMP_1 pin, the alignment slope is 500V / s, and the open-loop duty cycle is 25%.

[0036] According to the above-mentioned motor driving circuit for the downhole water distributor, the connection between the control chip and the driving chip can achieve the drive control of the brushless motor without the need for software control algorithm and speed feedback sensor circuit, thereby improving the working stability and reliability of the motor of the downhole water distributor.

[0037] Below, reference Figures 1 to 4 The motor driving circuit for the downhole water distributor in this example embodiment is described in more detail.

[0038] Optionally, refer to Figure 1 and Figure 2 As shown in , the operation signal includes: steering control signal, brake signal and enable signal; the status signal includes speed feedback signal and fault signal. It should be understood that the control circuit outputs forward and reverse, brake and stop signals to the motor drive circuit to control the normal operation of the motor, and receives the speed and fault signals output by the motor drive chip to determine the state of the motor operation.

[0039] Optionally, refer to Figure 1 and Figure 2 As shown in , the driving circuit includes a potentiometer Rw1, the two ends of the potentiometer Rw1 are connected to the second power supply and ground, and the center tap of the potentiometer is connected to the pin of the driving chip U1, which is used to configure the speed of the brushless motor. It should be understood that Rw1 is a potentiometer, the two pins are connected to +3.3V and AGND respectively, and the center tap is connected to the SPEED pin of U1 to control the motor speed. At the same time, the SPEED pin is also connected to the control circuit; BREAK is the brake control signal input, which is connected to the control circuit.

[0040] Optionally, refer to Figure 1 and Figure 2As shown in the figure, the driver chip U1 uses the integrated circuit chip MCT8316A1TRGFR, and the total power supply is 24VDC. It should be understood that the drive circuit is the core part of the motor drive circuit. The circuit is a single-chip structure, and the peripheral circuit only needs a small number of resistors and capacitors. The code-free, sensor-free high-speed integrated motor driver chip MCT8316A1TRGFR is used. The VM pin of the driver chip U1 is the power supply pin, which is powered by 24VDC. C1 and C2 are the voltage stabilizing and filtering capacitors of the 24VDC power supply; the OUT_A, OUT_B, and OUT_C ​​pins are output to the three-phase brushless motor to drive the motor; SW_BK is the switch node of the internal BUCK regulator of U1; FB_BK is the voltage feedback node of the internal BUCK regulator of U1; the CP pin is the charge pump output pin, which is connected to 24VDC through C5; CPH and CPL are the charge pump switch nodes, and the two pins are connected through C4. All NC pins have no internal electrical connection and are connected to AGND; PGND and PowerPAD pins are connected to PGND; LDANGLE, CONFIG_1, CONFIG_2, CONFIG_3, SLEW_RATE, ILIMIT, RMP_1, and RMP_2 pins are parameter configuration pins and are connected to AGND through configuration resistors; M1 is a three-phase brushless motor.

[0041] Optionally, refer to Figure 1 and Figure 2 As shown in , the driver chip U1 is connected to the center tap of the potentiometer by the SPEED pin, the brake signal is input by the BREAK pin, the steering control signal is input by the DIR pin, the enable signal is input by the DRVOFF pin, the speed feedback signal is output by the FG pin, and the fault signal is output by the FAULT pin. It should be understood that DIR is the motor steering control signal input, which is connected to the control circuit; DRVOFF is the drive enable signal input, which is connected to the control circuit; the FG pin is the motor speed feedback signal, which is connected to the control circuit, and this pin needs to be connected to the pull-up resistor R13; the FAULT pin is the fault signal output, which is connected to the control circuit, and this pin needs to be connected to the pull-up resistor R12.

[0042] Optionally, refer to Figure 1 and Figure 2 As shown in FIG. 1 , the driver chip U1 configures the minimum duty cycle of the pulse width modulation by the resistor connected to the CONFIG_3 pin. It should be understood that the driver chip U1 configures the PWM minimum duty cycle to be 5% and the abnormal speed frequency to be 4KHz through R5 connected to the CONFIG_3 pin.

[0043] Optionally, refer to Figure 1 and Figure 2As shown in , the driver chip U1 configures the first power supply through the resistor connected to the SLEW_RATE pin. It should be understood that the driver chip U1 configures the BUCK regulator to output 5V through R6 connected to the SLEW_RATE pin, and the slew rate is 50V / us.

[0044] Optionally, refer to Figure 1 and Figure 3 As shown in the figure, the first power supply is 5VDC, and the power supply circuit uses LDO chip U2 to convert the first power supply into the second power supply. It should be understood that the power supply circuit uses BUCK circuit to convert the DC power output by the integrated circuit chip MCT8316A1TRGFR into 5.0VDC output. The power supply circuit uses LDO integrated circuit chip LD1086DT33TR to convert 5.0VDC into 3.3VDC for use by the control circuit. The peripheral circuit composed of inductors L1, L2, resistors R1, and capacitors C3 is connected to the Figure 2 The BUCK regulator inside U1 forms a complete BUCK power supply circuit, outputting +5V DC power supply; +5VDC is converted into +3.3V DC power supply by LDO chip U2 and supplied to the control circuit; C6 and C7 are +5VDC voltage stabilizing filter capacitors; C8 and C9 are +3.3VDC voltage stabilizing filter capacitors; the power ground PGND and the signal ground AGND are connected through a 0 ohm resistor R8. Among them, the power circuits L1 and L2 are magnetically shielded high temperature inductors.

[0045] Optionally, refer to Figure 1 and Figure 4 As shown in , the control chip U3 uses an MCU chip, and the second power supply is 3.3VDC. It should be understood that the control circuit MCU uses an integrated circuit chip PIC18LF14K50-E / SS, which is used to control the start, stop, forward and reverse operation modes of the motor. P1 is a program download and debugging interface socket, which connects the MCLR, +3.3V, GND, PGD, and PGC pins of U3.

[0046] Optionally, refer to Figure 1 and Figure 4 As shown in the figure, the control chip U3 outputs the brake signal from the RC4 pin, the steering control signal from the RC3 pin, the enable signal from the RC6 pin, the speed feedback signal from the RC5 / CCP pin, and the fault signal from the RC1 pin. It should be understood that the control chip U3 uses an internal oscillator to work, the RA4 pin is the oscillator signal output; MCLR is the power-on reset pin, connected to +3.3VDC through R11; C10 and C11 are +3.3VDC voltage stabilizing filter capacitors; RC5 / CCP pin is connected to Figure 2 The FG pin of the driver chip is used to collect the motor speed pulse signal; the RC4 pin is connected to Figure 2The driver chip BREAK pin is used to control the motor brake; the RC3 pin is connected to Figure 2 The driver chip DIR pin is used to control the motor rotation direction; the RC6 pin is connected to Figure 2 The DRVOFF pin of the driver chip is used to enable the motor drive circuit inside the motor driver chip; the RC0 pin is connected to Figure 2 The SPEED pin of the driver chip is used to collect the level of the speed control potentiometer to monitor the motor speed configuration parameters; the RC1 pin is connected to Figure 2 The FAULT pin of the driver chip is used to receive the fault signal from the driver chip so as to stop the motor in time and play a protective role.

[0047] Those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the utility model disclosed herein. It is intended to cover any variation, use or adaptation of the present invention, which follows the general principles of the present invention and includes common knowledge or conventional technical means in the art that are not disclosed in the present invention.

Claims

1. A motor drive circuit for a downhole water distributor, characterized in that: include: A drive circuit, the drive circuit comprising a drive chip, the drive chip is provided with a pin connected to a main power supply, a pin connected to a power supply circuit and outputting a first power supply matching the power supply circuit, a pin connected to a brushless motor and driving the brushless motor to operate, and a pin connected to a control circuit and used to feed back a status signal to the control circuit and receive an operation signal transmitted by the control circuit; A power supply circuit, the power supply circuit is connected to the pin of the driving chip outputting the first power supply, is provided with an operational amplifier for stepping down the first power supply, and outputs a second power supply matching the control circuit; A control circuit, the control circuit includes a control chip, the control chip is provided with a pin connected to the second power supply, is provided with a pin connected to the drive circuit and is used to output the operation signal to the drive chip and collect the status signal; the control chip adjusts the output operation signal according to the collected status signal.

2. The motor driving circuit for a downhole water distributor according to claim 1, characterized in that: The operation signal includes: a steering control signal, a brake signal and an enable signal; the status signal includes a speed feedback signal and a fault signal.

3. The motor driving circuit for a downhole water distributor according to claim 2, characterized in that: The driving circuit comprises a potentiometer, two ends of the potentiometer are connected to the second power supply and ground, and a center tap of the potentiometer is connected to a pin of the driving chip for configuring the rotation speed of the brushless motor.

4. The motor driving circuit for a downhole water distributor according to claim 3, characterized in that: The driving chip adopts the integrated circuit chip MCT8316A1TRGFR, and the total power supply is 24VDC.

5. The motor driving circuit for a downhole water distributor according to claim 4, characterized in that: The drive chip is connected to the center tap of the potentiometer via the SPEED pin, the brake signal is input via the BREAK pin, the steering control signal is input via the DIR pin, the enable signal is input via the DRVOFF pin, the speed feedback signal is output via the FG pin, and the fault signal is output via the FAULT pin.

6. The motor driving circuit for a downhole water distributor according to claim 4, characterized in that: The driver chip configures the minimum duty cycle of the pulse width modulation by a resistor connected to the CONFIG_3 pin.

7. The motor driving circuit for a downhole water distributor according to claim 4, characterized in that: The driver chip configures the first power supply through a resistor connected to the SLEW_RATE pin.

8. The motor driving circuit for a downhole water distributor according to claim 1, characterized in that: The first power supply is 5VDC, and the power supply circuit uses an LDO chip to convert the first power supply into the second power supply.

9. The motor driving circuit for a downhole water distributor according to claim 2, characterized in that: The control chip is an MCU chip, and the second power supply is 3.3 VDC.

10. The motor driving circuit for a downhole water distributor according to claim 9, characterized in that: The control chip outputs the brake signal through the RC4 pin, outputs the steering control signal through the RC3 pin, outputs the enable signal through the RC6 pin, collects the speed feedback signal through the RC5 / CCP pin, and collects the fault signal through the RC1 pin.

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