Five-wire stepping motor closed-loop control circuit and method

Abstract

The invention discloses a five-wire stepping motor closed-loop control circuit and a five-wire stepping motor closed-loop control method, relates to the technical field of stepping motor control, and aims to solve the problem that the design difficulty of a mechanical structure and the overall cost of a product are increased in an existing stepping motor control mode. The MCU module is respectively connected with a detection module and a driving module, the detection module is connected with the driving module, the driving module comprises a driving chip, the driving chip is connected with a controlled stepping motor and drives the controlled stepping motor to execute actions, the power supply module is further connected with the detection module and a communication module, and the communication module is connected with external equipment and performs data interaction. According to the invention, the closed-loop control of the five-wire stepping motor can be realized without a tail end sensor, and the cost is obviously reduced.

Description

Technical Field

[0001] The invention relates to the technical field of stepper motor control, and in particular to a five-wire stepper motor closed-loop control circuit and method. Background Art

[0002] With the widespread application of stepper motors in equipment, precise control of stepper motors is particularly important. Existing stepper motors are mostly open-loop controlled. Although sensors or rigid structures can be added to the end of the mechanical structure to achieve position detection or limitation, this will undoubtedly increase the difficulty of mechanical structure design and the overall cost of the product. Therefore, the existing stepper motor control method is not the best choice.

[0003] The Chinese patent with the announcement number CN110620530A discloses a positioning control method, device, equipment and medium for a stepper motor, wherein the stator and rotating mechanism of the stepper motor are respectively provided with a Hall sensor and a magnetic steel, including: when the open-loop control system is powered on, a target control instruction is sent to the stepper driver to drive the stepper motor to drive the magnetic steel on the rotating mechanism to operate; when the magnetic steel is in operation, the target reading of the flag is detected in real time; when the stepper motor is in the forward state and the target reading jumps from the first flag to the second flag, or when the stepper motor is in the reverse state and the target reading jumps from the second flag to the first flag, the stepper motor is controlled to stop running, the stop position of the rotor of the stepper motor is set to the target position, and the operating angle of the stepper motor is positioned with the target position as the initial position. However, the Chinese patent with the announcement number CN110620530A still needs to add a Hall sensor, which increases the design difficulty of the mechanical structure and the overall cost of the product. Summary of the invention

[0004] The present invention solves the problem that the existing stepper motor control method increases the design difficulty of the mechanical structure and the overall cost of the product, and proposes a five-wire stepper motor closed-loop control circuit and method, which can achieve closed-loop control of the five-wire stepper motor without an end sensor, thereby significantly reducing the cost.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a five-wire stepper motor closed-loop control circuit, comprising an MCU module and a power supply module connected to the MCU module, the MCU module is respectively connected to a detection module and a drive module, the detection module and the drive module are connected, the drive module comprises a drive chip, the drive chip is connected to a controlled stepper motor and drives the controlled stepper motor to perform an action, the power supply module is also connected to a detection module and a communication module, the communication module is connected to an external device and performs data exchange.

[0006] The technical solution consists of a power module, a drive module, a detection module, an MCU module and a communication module. The circuit framework is simple and can realize closed-loop control of the stepper motor. While the MCU module controls the drive module to drive the controlled stepper motor to operate, the detection module can obtain the current value flowing through the controlled stepper motor in real time under the current operation, and can be connected to other external devices through the communication module to ensure data interaction with the outside world.

[0007] The present invention is further configured as follows: the input ports of the driving chip are respectively connected to a plurality of current limiting resistors, the other side of the current limiting resistors are connected to the MCU module, and the grounding end of the driving chip is respectively connected to the resistor RS1 and the detection module.

[0008] In this technical solution, several current-limiting resistors connected to the driver chip can play a role in current limiting and improving anti-interference ability, and the current-limiting resistors can be connected to the MCU module; the driver chip is also connected to the resistor RS1 and the detection module respectively.

[0009] The present invention is further configured as follows: the detection module includes a detection chip, the in-phase input end of the detection chip is connected to a resistor R6, the inverting input end of the detection chip is respectively connected to resistors R7 and R8, and the other side of the resistor R7 is connected to the output end of the detection chip.

[0010] In this technical solution, resistor R6 plays the role of current limiting and improving anti-interference ability. The detection chip is specifically an operational amplifier, which forms a common-mode amplifier with resistors R7 and R8. Resistors R7 and R8 form a resistor voltage divider network.

[0011] The present invention is further configured as follows: the MCU module includes a control chip, four IO ports of the control chip are connected to the current limiting resistor in the driving module, and the IO5 port of the control chip is connected to the detection module.

[0012] In this technical solution, the IO1~IO4 ports of the control chip are all connected to the corresponding current limiting resistors in the driving module, and are connected to the driving module through the current limiting resistors, and the IO5 port of the control chip is connected to the resistor R9 of the detection module.

[0013] The present invention is further configured as follows: the output end of the detection chip is also connected to a resistor R9, and the resistor R9 is connected to the IO5 port of the control chip.

[0014] In this technical solution, the resistor R9 also plays the role of limiting current and improving anti-interference capability.

[0015] The present invention is further configured as follows: the power module comprises a power chip, an input port of the power chip is connected to an input filter group, and an output port of the power chip is connected to an output filter group.

[0016] In this technical solution, the power chip in the power module can provide power for the back-end MCU module, detection module and communication module.

[0017] The present invention is further configured as follows: the driving chip is a Darlington transistor array, the driving chip receives a small current signal received by its input port, and drives the controlled stepping motor through the output port of the driving chip.

[0018] In this technical solution, the output port of the driving chip is connected to the terminal CN3, and the terminal CN3 is connected to the controlled stepping motor.

[0019] The present invention is further configured as follows: the input filter group includes a capacitor EC1 and a capacitor C1 connected in parallel to each other, and the output filter group includes a capacitor EC2 and a capacitor C2 connected in parallel to each other.

[0020] In this technical solution, double filtering is performed through an input filter group and an output filter group to ensure voltage stability.

[0021] The present invention is further configured as follows: the communication module includes a terminal CN2, and the terminal CN2 is connected to the communication port of the MCU module.

[0022] In this technical solution, the communication module can communicate and interact with external devices.

[0023] A five-wire stepper motor closed-loop control method, using the above-mentioned five-wire stepper motor closed-loop control circuit, comprises the following steps: S1, the driving module drives the controlled stepper motor to start running, and the detection module obtains the current value flowing through the controlled stepper motor in real time; S2, judging the operating state of the controlled stepper motor, judging whether the deviation between the current value and the preset current value is within a preset range, if so, the controlled stepper motor is in a normal operating state, if not, entering S3; S3, judging the specific abnormal state of the controlled stepper motor under the current operation according to the change direction, difference and slope of the deviation value.

[0024] In this technical solution, while the MCU module controls the driving module to drive the controlled stepper motor to operate, the detection module obtains the current value flowing through the controlled stepper motor in real time under the current operation. The current value is compared with the set current value. If the deviation value is within the set range, the operating state of the controlled stepper motor under the current operation is consistent with the demand. If the deviation value exceeds the set range, the abnormal state of the controlled stepper motor under the current operation can be comprehensively judged according to the direction of the deviation value change, the difference and the slope, thereby realizing the closed-loop control of the five-wire stepper motor.

[0025] The present invention can bring the following beneficial effects: 1. The invention relates to a five-wire stepper motor closed-loop control circuit, which realizes closed-loop control of the five-wire stepper motor without an end sensor, thus significantly reducing the cost; 2. The control circuit functional framework of the present invention is simple and easy to implement, and can flexibly adapt to five-wire stepping motors with different parameters; 3. Communicate with external devices through the communication module to facilitate data interaction and intelligent control; 4. Release the internal space of the product and improve the design flexibility and utilization rate of the end space of the mechanical structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of a five-wire stepper motor closed-loop control circuit power module of the present application.

[0027] Figure 2 It is a schematic diagram of an MCU module of a five-wire stepper motor closed-loop control circuit of the present application.

[0028] Figure 3 It is a schematic diagram of a five-wire stepper motor closed-loop control circuit drive module of the present application.

[0029] Figure 4 It is a schematic diagram of a five-wire stepper motor closed-loop control circuit detection module of the present application.

[0030] Figure 5 It is a schematic diagram of a five-wire stepper motor closed-loop control circuit communication module of the present application. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific implementation method described herein is only an optimal embodiment of the present invention, which is only used to explain the present invention and does not limit the scope of protection of the present invention. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0032] The present invention relates to the field of stepper motor control technology. Stepper motors are provided in some devices such as fans, air conditioners, humidifiers, coffee machines or water dispensers. Stepper motors are used to control the position and speed of mechanical structures according to actual application scenarios, and to detect various parameters during the movement process in real time.

[0033] In order to increase customer attention, meet customer needs, and stimulate purchasing desire in the existing market environment, more and more electrical appliance manufacturers have put forward more novel and detailed requirements on product functions and controls. Based on this demand, stepper motors that can achieve segmented control and have a high cost-effectiveness have become the best choice at present. The coordination between stepper motors and mechanical structures makes it possible to quantitatively control functional requirements such as circular motion, linear stroke, and motion state, thereby further refining various parameters and designing various eye-catching products. Most existing stepper motors use open-loop control. Although sensors or rigid structures can be added at the end of the mechanical structure to achieve position detection or limitation, this will undoubtedly increase the design difficulty of the mechanical structure and the overall cost of the product.

[0034] Example 1 In view of the above technical problems, this embodiment proposes a five-wire stepper motor closed-loop control circuit. Figures 1 to 5 It mainly includes an MCU module and a power module. The MCU module is connected to the power module. The MCU module is also connected to the detection module and the driving module respectively. The detection module is connected to the driving module. The driving module mainly includes a driving chip. The driving chip can be connected to the controlled stepper motor, and the driving chip can drive the controlled stepper motor to perform corresponding actions. The power module is also connected to the detection module and the communication module respectively. The communication module is connected to the external device and can ensure data interaction with the external device.

[0035] The technical solution consists of a power module, a drive module, a detection module, an MCU module and a communication module. The circuit framework is simple and can realize closed-loop control of the stepper motor. While the MCU module controls the drive module to drive the controlled stepper motor to operate, the detection module can obtain the current value flowing through the controlled stepper motor in real time under the current operation, and can be connected to other external devices through the communication module to ensure data interaction with the outside world.

[0036] refer to Figure 3 In the driver module, the input port of the driver chip of the driver module is connected to several current limiting resistors, the other side of the current limiting resistor is connected to the MCU module, and the ground terminal of the driver chip is connected to the resistor RS1 and the detection module. Figure 3 The chip U2 in the .

[0037] The driving chip is specifically a Darlington transistor array, which receives a small current signal received by its input port and drives the controlled stepper motor through the output port of the driving chip. The output port of the driving chip is connected to the terminal CN3, and the terminal CN3 is connected to the controlled stepper motor.

[0038] More specifically, the several current limiting resistors are resistor R2, resistor R3, resistor R4, and resistor R5; resistor R2 is connected to the first input port of the driving chip, resistor R3 is connected to the second input port of the driving chip, resistor R4 is connected to the third input port of the driving chip, and resistor R5 is connected to the fourth input port of the driving chip.

[0039] The side of the resistor R2 away from the driver chip is recorded as SM A, the side of the resistor R2 away from the driver chip is recorded as SM B, the side of the resistor R2 away from the driver chip is recorded as SM C, and the side of the resistor R2 away from the driver chip is recorded as SM D. Among them, SM A, SMB, SM C and SM D are all connected to the MCU module.

[0040] In addition, for the grounding end of the driving chip, one of the lines is connected to the resistor RS1, the other side of the resistor RS1 is grounded, and the other line is directly connected to the detection module, that is, the non-grounding end of the resistor RS1 is connected to the detection module.

[0041] The terminal CN3, the resistor R2, the resistor R3, the resistor R4, the resistor R5, the resistor RS1, the capacitor EC3, the capacitor C3 and the chip U2 together constitute the above-mentioned driving module.

[0042] Specifically, the terminal CN3 is connected to the controlled stepper motor. The terminal CN3 includes an A-phase port, a B-phase port, a C-phase port, a D-phase port and a power port. The A-phase port is connected to the output port of the driver chip. Specifically, the A-phase port is connected to the 1C port of the driver chip. Similarly, the B-phase port is connected to the 2C port of the driver chip, the C-phase port is connected to the 3C port of the driver chip, and the D-phase port is connected to the 4C port of the driver chip.

[0043] Resistors R2, R3, R4 and R5 have the function and effect of limiting current and improving anti-interference capability.

[0044] Capacitor EC3 and capacitor C3 are connected in parallel, one end of capacitor EC3 and capacitor C3 are grounded, and the other end of EC3 and capacitor C3 are connected to the filter port of the driver chip, which is port 6 in the figure. The function of capacitor EC3 and capacitor C3 is power supply filtering, which can provide stable power for the driver chip and the controlled stepper motor.

[0045] Chip U2, i.e. the driver chip, is a Darlington transistor array and can receive Figure 3 The small current signal on the B port in the chip is used to drive the controlled stepper motor to perform the corresponding action through the C port. Among them, the B port is the input port of the driver chip, and the C port is the output port of the driver chip.

[0046] The B port mainly includes a 1B port, a 2B port, a 3B port and a 4B port. The 1B port is connected to the resistor R2, the 2B port is connected to the resistor R3, the 3B port is connected to the resistor R4, and the 4B port is connected to the resistor R5.

[0047] Resistor RS1 is connected to the ground terminal of the driver chip. It is a ground bus current detection resistor. After the load current flows through terminal CN3, the controlled stepper motor, and the C port of the driver chip, it will flow out from the ground terminal of the driver chip. The current then flows to GND through resistor RS1 and generates a certain potential difference at both ends of resistor RS1. Since one end of resistor RS1 is connected to GND, the voltage of the non-grounded end of resistor RS1 to the ground is equal to the potential difference. The voltage of the non-grounded end of resistor RS1 is transmitted to the detection module to obtain the current flowing through the driver chip.

[0048] In the above technical solution, several current limiting resistors connected to the driver chip can play the role of current limiting and improving anti-interference ability, and the current limiting resistors can be connected to the MCU module; the driver chip is also connected to the resistor RS1, and the other end of the resistor RS1 is connected to the detection module.

[0049] refer to Figure 4 The detection module mainly includes a detection chip, which is Figure 4 The chip U3 in the detection chip, wherein the in-phase input terminal of the detection chip is connected to the resistor R6, the inverting input terminal of the detection chip is respectively connected to the resistor R7 and the resistor R8, and the other side of the resistor R7 is connected to the output terminal of the detection chip.

[0050] The output end of the detection chip is also connected to the resistor R9, and the resistor R9 is also connected to the IO5 port of the control chip.

[0051] The detection chip is an operational amplifier, the fifth port of the detection chip is connected to the power supply terminal, and the second port of the detection chip is grounded. One end of the resistor R6 is connected to the ground terminal of the driving chip, and the other end of the resistor R6 is connected to the in-phase input terminal of the detection chip.

[0052] For resistors R7 and R8, one end of each is connected to the inverting input end of the detection chip, the other end of resistor R7 is connected to the output end of the detection chip or one side of resistor R9, and the other end of resistor R8 is grounded.

[0053] In the above technical solution, resistor R6 plays the role of current limiting and improving anti-interference ability. The detection chip is specifically an operational amplifier, which forms a common-mode amplifier with resistors R7 and R8. Resistors R7 and R8 form a resistor voltage divider network.

[0054] refer to Figure 4In more detail, resistor R6, resistor R7, resistor R8, resistor R9, capacitor C5 and the detection chip together constitute the above-mentioned detection module.

[0055] Resistor R6 and resistor R9 can both limit current and improve anti-interference capability.

[0056] The function of capacitor C5 is power supply filtering, which can provide stable power for the detection chip.

[0057] The detection chip is an operational amplifier, which together with resistors R7 and R8 forms a common-mode amplifier.

[0058] The in-phase input terminal of the detection chip is connected to the resistor R6, and the other end of the resistor R6 is connected to the non-grounded end of the resistor RS1 in the driving module, so as to send the ground voltage of the non-grounded end of the resistor RS1 to the detection chip.

[0059] The inverting input terminal of the detection chip is connected to resistors R7 and R8. Resistors R7 and R8 together form a resistor voltage divider network. The other end of resistor R7 is connected to the output terminal of the detection chip, and the other end of resistor R8 is grounded. The voltage at the non-grounded end of resistor RS1 is amplified by utilizing the characteristics of the common-mode amplifier, and then sent to the MCU module for subsequent processing after setting the corresponding multiple.

[0060] refer to Figure 2 , the MCU module mainly includes the control chip. The control chip is Figure 2 The chip U4 in the control chip; the four IO ports of the control chip are connected to the current limiting resistor of the driving module, and the IO5 port of the control chip is connected to the detection module.

[0061] More specifically, the four IO ports of the control chip are IO1 port, IO2 port, IO3 port and IO4 port, respectively. The IO1 port is connected to the above-mentioned SM A, and is connected to the resistor R2 through SM A. The IO2 port is connected to the above-mentioned SM B, and is connected to the resistor R3 through SM B. The IO3 port is connected to the above-mentioned SM C, and is connected to the resistor R3 through SM C. The IO4 port is connected to the above-mentioned SM D, and is connected to the resistor R4 through SM D.

[0062] In the above technical solution, the IO1, IO2, IO3 and IO4 ports of the control chip are all connected to the corresponding current limiting resistors in the driving module, and the driving module is connected through the current limiting resistors, and the IO5 port of the control chip is connected to the resistor R9 of the detection module.

[0063] More specifically, referring to 2, the control chip, capacitor EC4 and capacitor C4 together constitute the MCU module.

[0064] Capacitor EC4 and capacitor C4 are connected in parallel, one end of capacitor EC4 and capacitor C4 are grounded, and the other end of capacitor EC4 and capacitor C4 are connected to the power supply end. Capacitor EC4 and capacitor C4 both have the function of power supply filtering, and both can provide stable power for chip U4.

[0065] The IO1 port, IO2 port, IO3 port and IO4 port of the control chip are connected to the B port of the control chip through the current limiting resistor (including resistor R2, resistor R3, resistor R4 and resistor R5) in the driving module, which can mainly control the power supply logic of the controlled stepper motor coil.

[0066] The IO5 port of the control chip is connected to the output end of the detection chip through the current limiting resistor R9 in the detection module, and can read the voltage value of the output end of the chip U3 to the ground.

[0067] The IO6 port and IO7 port of the control chip are respectively connected to the communication module, which can realize the function of communicating with external devices.

[0068] refer to Figure 1 The power module mainly includes a power chip, which is Figure 1 The chip U1 in the power module can supply power to the MCU module, the detection module and the communication module at the back end.

[0069] Furthermore, the input filter group includes capacitor EC1 and capacitor C1, which are connected in parallel, and the output filter group includes capacitor EC2 and capacitor C2, which are connected in parallel. In this embodiment, double filtering is performed by the input filter group and the output filter group to ensure voltage stability.

[0070] One end of capacitor EC1 and capacitor C1 are connected to the input port of the power chip, and the other end of capacitor EC1 and capacitor C1 are grounded. Similarly, one end of capacitor EC2 and capacitor C2 are connected to the input port of the power chip, and the other end of capacitor EC2 and capacitor C2 are grounded.

[0071] In more detail, the terminal CN1, the resistor R1, the capacitor EC1, the capacitor EC2, the capacitor C1, the capacitor C2 and the power chip together constitute a power module.

[0072] The terminal CN1 can be connected to an external power supply device.

[0073] One end of the resistor R1 is connected to the terminal CN1 , and the other end of the resistor R1 is connected to the input port of the power chip.

[0074] Resistor R1 can limit the current and reduce the power consumption of the power chip. Capacitor EC1 and capacitor C1 can perform input filtering on the power chip. Capacitor EC2 and capacitor C2 can perform output filtering on the power chip. The power chip supplies power to the back-end MCU module, detection module and communication module.

[0075] refer to Figure 5 The communication module includes a terminal CN2, and the terminal CN2 is connected to the communication port of the MCU module. The communication module is used to realize communication interaction with external devices.

[0076] This embodiment can also bring the following technical effects: 1. The functional framework of the circuit is simple and easy to implement, and can flexibly adapt to five-wire stepper motors with different parameters; 2. Release the internal space of the product and improve the design flexibility and utilization rate of the end space of the mechanical structure; 3. The circuit can communicate with external devices to facilitate data interaction and intelligent control.

[0077] Example 2 On the basis of Example 1, this example further proposes a five-wire stepping motor closed-loop control method, which mainly includes the following steps.

[0078] Step S1, first, the driving module drives the controlled stepping motor to start running, and the detection module obtains the current value flowing through the controlled stepping motor in real time; Step S2, then, determine the operating state of the controlled stepper motor, and determine whether the deviation value between the current value and the preset current value is within a preset range. If so, the controlled stepper motor is in a normal operating state. If not, proceed to step S3; Step S3, finally, determine the specific abnormal state of the controlled stepper motor under the current operation according to the change direction, difference and slope of the deviation value.

[0079] More specifically, while the MCU module controls the driving module to drive the controlled stepper motor to operate, the detection module obtains the current value flowing through the controlled stepper motor in real time under the current operation. The current value is compared with the set current value. If the deviation value is within the set range, the operating state of the controlled stepper motor under the current operation is consistent with the demand. If the deviation value exceeds the set range, the abnormal state of the controlled stepper motor under the current operation can be comprehensively judged according to the direction of the deviation value change, the difference and the slope, thereby realizing the closed-loop control of the five-wire stepper motor.

[0080] In addition, the principle of closed-loop control also includes the following several detection methods.

[0081] Motor connection detection is specifically as follows: when it is necessary to detect whether the controlled stepper motor is connected, all coils of the controlled stepper motor can be powered at the same time. At this time, the MCU module detects whether the current on the resistor RS1 is normal through the detection module, and then determines whether the controlled stepper motor is connected.

[0082] Lost-step detection is specifically as follows: in the process of driving the controlled stepper motor to operate normally, the total current flowing through the controlled stepper motor is detected in real time. If the current is consistent with when the controlled stepper motor is powered off, it is considered to be in a lost-step state. For example, the MCU module requires the drive module to power phase A of the controlled stepper motor, but no corresponding current is detected flowing through the resistor RS1 at this time, which means that it is currently in a lost-step state.

[0083] Out-of-step detection is specifically as follows: in the process of driving the controlled stepper motor to operate normally, the total current flowing through the controlled stepper motor is detected in real time. If the current is significantly greater than the set current under the current step, it is considered that the controlled stepper motor is currently in an out-of-step state. For example: the MCU module requires the drive module to power phase A of the controlled stepper motor, but the current detected on the resistor RS1 at this time is much greater than the current when phase A is operating normally, that is, it can be considered that it is currently in an out-of-step state.

[0084] Stall detection is specifically as follows: based on the above out-of-step detection process, if the current detected on the resistor RS1 detected in several consecutive cycles is greater than the current set under each operation, it can be considered that the controlled stepper motor is currently in a stalled state.

[0085] Torque control, specifically: the stepper motor essentially generates a rotating magnetic field by controlling the power supply logic of each coil on the stator, and the strength of the magnetic field is related to the current strength flowing through the coil. The stronger the magnetic field, the stronger the attraction and repulsion to the permanent magnet on the rotor, and the greater the final output torque. By introducing the detection module, the closed loop of the control system is realized, and the total current flowing through the controlled stepper motor can be detected. With the help of the MCU module, the coil power supply logic of the minimum unit time in a cycle can be further subdivided, and the coil can be powered in the form of PWM. The strength of the magnetic field generated by the stator is controlled by controlling the current strength flowing through the coil, thereby achieving control of the rotor output torque.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention is described in detail with reference to the embodiments, it should be understood by those skilled in the art that any modification or equivalent replacement of the technical solutions of the present invention does not depart from the spirit and scope of the technical solutions of the present invention and should be included in the scope of the claims of the present invention.

Claims

1. A five-wire stepper motor closed-loop control circuit, characterized in that: It includes an MCU module and a power module connected to the MCU module, the MCU module is respectively connected to a detection module and a drive module, the detection module and the drive module are connected, the drive module includes a drive chip, the drive chip is connected to a controlled stepper motor and drives the controlled stepper motor to perform an action, the power module is also connected to a detection module and a communication module, the communication module is connected to an external device and performs data exchange.

2. A five-wire stepping motor closed-loop control circuit according to claim 1, characterized in that: The input ports of the driving chip are respectively connected to a plurality of current limiting resistors, the other side of the current limiting resistors is connected to the MCU module, and the grounding end of the driving chip is respectively connected to the resistor RS1 and the detection module.

3. A five-wire stepping motor closed-loop control circuit according to claim 1, characterized in that: The detection module includes a detection chip, a resistor R6 is connected to the in-phase input end of the detection chip, a resistor R7 and a resistor R8 are connected to the inverting input end of the detection chip, and the other side of the resistor R7 is connected to the output end of the detection chip.

4. A five-wire stepping motor closed-loop control circuit according to claim 2, characterized in that: The MCU module comprises a control chip, four IO ports of the control chip are connected to the current limiting resistor in the driving module, and the IO5 port of the control chip is connected to the detection module.

5. A five-wire stepping motor closed-loop control circuit according to claim 4, characterized in that: The output end of the detection chip is also connected to a resistor R9, and the resistor R9 is connected to the IO5 port of the control chip.

6. A five-wire stepping motor closed-loop control circuit according to any one of claims 1 to 5, characterized in that: The power module comprises a power chip, an input port of the power chip is connected to an input filter group, and an output port of the power chip is connected to an output filter group.

7. A five-wire stepping motor closed-loop control circuit according to any one of claims 1 to 5, characterized in that: The driving chip is a Darlington transistor array. The driving chip receives a small current signal received by its input port and drives the controlled stepping motor through the output port of the driving chip.

8. A five-wire stepping motor closed-loop control circuit according to claim 6, characterized in that: The input filter group includes a capacitor EC1 and a capacitor C1 connected in parallel to each other, and the output filter group includes a capacitor EC2 and a capacitor C2 connected in parallel to each other.

9. A five-wire stepping motor closed-loop control circuit according to any one of claims 1 to 5, characterized in that: The communication module includes a terminal CN2, and the terminal CN2 is connected to the communication port of the MCU module.

10. A five-wire stepper motor closed-loop control method, using a five-wire stepper motor closed-loop control circuit according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, the driving module drives the controlled stepper motor to start running, and the detection module obtains the current value flowing through the controlled stepper motor in real time; S2, judging the operating state of the controlled stepper motor, judging whether the deviation between the current value and the preset current value is within a preset range, if so, the controlled stepper motor is in a normal operating state, if not, entering S3; S3, judging the specific abnormal state of the controlled stepper motor under the current operation according to the change direction, difference and slope of the deviation value.

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