A DC motor commutation circuit
By using the charging delay function of the capacitor in the DC motor commutation circuit, the new steering circuit is delayed and the original steering circuit is quickly closed, which solves the problem of sharp rise and short-circuit caused by the simultaneous opening of the controller output terminal, and realizes the problem of rapid rise and short-circuit in the short-term current caused by the simultaneous opening of the controller. Low-cost and high-reliability motor rotation direction switching.
Patent Information
- Application Number
- CN201811239796.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2018-10-23
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2038-10-23
AI Technical Summary
When the rotor rotation direction of the DC motor is switched, the two output terminals of the controller are turned on simultaneously, causing a sharp increase in the short-term current, which may even cause a short-circuit problem.
A DC motor commutation circuit including a first steering circuit, a second steering circuit, a first delay drive circuit, a second delay drive circuit and a steering shutdown circuit are designed. The charging delay function of the capacitor is used to carry out the motor. When the power supply direction changes, turn on the new steering circuit appropriately and quickly turn off the original steering circuit to avoid a sharp rise in the short-term current and short-circuit.
It effectively avoids the problem of sharp rise in short-term current and short-circuit problems. Only one motor commutation control terminal is used, which is low in cost, simple in structure and high reliability.
Smart Images
Figure CN109347377B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of motor control, and in particular to a commutation circuit for a direct current motor. Background Art
[0002] DC motors are widely used in medical devices, robots and other fields. In practical applications, DC motors generally encounter the problem of motor rotor rotation, that is, the rotor switches from clockwise rotation to counterclockwise rotation, or the rotor switches from counterclockwise rotation to clockwise rotation. Traditional control methods generally use different output ends of controllers such as PLCs or single-chip microcomputers to control the rotor to rotate clockwise or counterclockwise. When switching, one end stops working and the other end starts working to switch the rotation direction of the rotor. However, in the long-term operation of the controller, it is inevitable that the controller will restart or the program will run away. In this case, once the two control ends are turned on at the same time, it will cause a short-term current surge or even a short circuit. Summary of the invention
[0003] In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide a DC motor commutation circuit, which solves the problem in the prior art that the two control terminals of the controller are turned on at the same time, causing a short-term current surge or even a short circuit.
[0004] The present invention provides a DC motor commutation circuit, comprising a first steering circuit, a second steering circuit, a first delay drive circuit, a second delay drive circuit, and a steering shut-off circuit, wherein a motor commutation control terminal is connected to an input terminal of the first delay drive circuit, an output terminal of the first delay drive circuit is connected to a DC motor via the first steering circuit, the motor commutation control terminal is connected to an input terminal of the second delay drive circuit, an output terminal of the second delay drive circuit is connected to a DC motor via the second steering circuit, the motor commutation control terminal is connected to an input terminal of the steering shut-off circuit, and an output terminal of the steering shut-off circuit is connected to a DC motor via the first steering circuit.
[0005] Furthermore, it also includes a motor control circuit, the motor stop rotation control terminal is connected to the input terminal of the motor control circuit, and the output terminal of the motor control circuit is connected through the first steering circuit and the second steering circuit respectively.
[0006] Further, the first steering circuit includes a first power supply, a first PMOS tube, a first NMOS tube, a first resistor, and a second resistor. The first power supply is connected to the source of the first PMOS tube, the drain of the first PMOS tube is connected to the first power input terminal of the DC motor, the gate of the first PMOS tube is connected to the first power supply through the first resistor, the first resistor is connected to the drain of the first NMOS tube through the second resistor, the drain of the first NMOS tube is connected to the second power input terminal of the DC motor, the source of the first NMOS tube is grounded, and the gate of the first NMOS tube is connected to the output terminal of the first delay drive circuit.
[0007] Furthermore, the second steering circuit includes a second power supply, a second PMOS tube, a second NMOS tube, a third resistor, and a fourth resistor. The second power supply is connected to the source of the second PMOS tube, the drain of the second PMOS tube is connected to the second power input terminal of the DC motor, the gate of the second PMOS tube is connected to the second power supply through the third resistor, the third resistor is connected to the drain of the second NMOS tube through the fourth resistor, the drain of the second NMOS tube is connected to the first power input terminal of the DC motor, the source of the second NMOS tube is grounded, and the gate of the second NMOS tube is connected to the output terminal of the second delay drive circuit.
[0008] Further, the first delay driving circuit includes a third power supply, a third PMOS tube, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, and a first capacitor. The third power supply is connected to the source of the third PMOS tube, the drain of the third PMOS tube is connected to the gate of the first NMOS tube through the fifth resistor, the sixth resistor and the first capacitor are connected in parallel between the gate and the source of the first NMOS tube, the gate of the third PMOS tube is connected to the third power supply through the seventh resistor, and the gate of the third PMOS tube is connected to the motor commutation control terminal through the eighth resistor.
[0009] Furthermore, the steering shutdown circuit includes a third NMOS tube, a ninth resistor, a tenth resistor, and an eleventh resistor, the drain of the third NMOS tube is connected to the gate of the first NMOS tube through the ninth resistor, the source of the third NMOS tube is grounded, the tenth resistor is connected between the source and the gate of the third NMOS tube, and the gate of the third NMOS tube is connected to the motor commutation control terminal through the eleventh resistor.
[0010] Furthermore, the second delay drive circuit includes a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a second capacitor, and a first diode. The gate of the second NMOS tube is connected to the positive electrode of the first diode through the twelfth resistor, the negative electrode of the first diode is connected to the motor commutation control end, the series branch of the twelfth resistor and the first diode is connected in parallel with the thirteenth resistor, and the fourteenth resistor and the second capacitor are connected in parallel between the gate and the source of the second NMOS tube.
[0011] Furthermore, the motor control circuit includes a fifteenth resistor, a second diode, and a third diode. The gate of the first NMOS tube is connected to the anode of the second diode, the cathode of the second diode is connected to the motor stop rotation control terminal through the fifteenth resistor, the gate of the second NMOS tube is connected to the anode of the third diode, and the cathode of the third diode is connected to the motor stop rotation control terminal through the fifteenth resistor.
[0012] Compared with the prior art, the present invention has the following beneficial effects:
[0013] The present invention provides a DC motor commutation circuit, including a first steering circuit, a second steering circuit, a first delay drive circuit, a second delay drive circuit, and a steering shutoff circuit. The motor commutation control terminal is connected to the first delay drive circuit input terminal, the first delay drive circuit output terminal is connected to the DC motor through the first steering circuit, the motor commutation control terminal is connected to the second delay drive circuit input terminal, the second delay drive circuit output terminal is connected to the DC motor through the second steering circuit, the motor commutation control terminal is connected to the steering shutoff circuit input terminal, and the steering shutoff circuit output terminal is connected to the DC motor through the first steering circuit. The present invention utilizes the charging delay function of the first capacitor and the second capacitor, and when the power supply direction of the DC motor changes, the opening time of the new steering circuit is appropriately delayed, and the original steering circuit is quickly closed at the same time, to ensure that the steering circuit will not have a short-term current surge or even a short circuit problem, and only uses one motor commutation control terminal, with low cost, simple structure and high reliability.
[0014] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. The specific implementation of the present invention is given in detail by the following embodiments and their accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:
[0016] Figure 1 A structural block diagram of a DC motor commutation circuit of the present invention;
[0017] Figure 2 The present invention is a circuit diagram of a DC motor commutation circuit according to an embodiment of the present invention. DETAILED DESCRIPTION
[0018] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.
[0019] A DC motor commutation circuit, such as Figure 1 As shown, it includes a first steering circuit, a second steering circuit, a first delay drive circuit, a second delay drive circuit, and a steering shut-off circuit. The motor reversing control terminal is connected to the input terminal of the first delay drive circuit, the output terminal of the first delay drive circuit is connected to the DC motor through the first steering circuit, the motor reversing control terminal is connected to the input terminal of the second delay drive circuit, the output terminal of the second delay drive circuit is connected to the DC motor through the second steering circuit, the motor reversing control terminal is connected to the input terminal of the steering shut-off circuit, and the output terminal of the steering shut-off circuit is connected to the DC motor through the first steering circuit.
[0020] like Figure 2 As shown, preferably, the first steering circuit includes a first power supply, a first PMOS transistor, a first NMOS transistor, a first resistor, and a second resistor. Figure 2 In the figure, the first power supply is represented by VCC, the first PMOS tube is represented by T1, the first NMOS tube is represented by T2, the first resistor is represented by R1, the second resistor is represented by R2, the DC motor is represented by M, the first power supply is connected to the source of the first PMOS tube, the drain of the first PMOS tube is connected to the first power input terminal of the DC motor, the gate of the first PMOS tube is connected to the first power supply through the first resistor, the first resistor is connected to the drain of the first NMOS tube through the second resistor, the drain of the first NMOS tube is connected to the second power input terminal of the DC motor, the source of the first NMOS tube is grounded, and the gate of the first NMOS tube is connected to the output terminal of the first delay driving circuit.
[0021] like Figure 2 As shown, preferably, the second steering circuit includes a second power supply, a second PMOS transistor, a second NMOS transistor, a third resistor, and a fourth resistor. Figure 2In the circuit, the second power supply is represented by VCC, the second PMOS tube is represented by T3, the second NMOS tube is represented by T4, the third resistor is represented by R3, the fourth resistor is represented by R4, the second power supply is connected to the source of the second PMOS tube, the drain of the second PMOS tube is connected to the second power supply input terminal of the DC motor, the gate of the second PMOS tube is connected to the second power supply through the third resistor, the third resistor is connected to the drain of the second NMOS tube through the fourth resistor, the drain of the second NMOS tube is connected to the first power supply input terminal of the DC motor, the source of the second NMOS tube is grounded, and the gate of the second NMOS tube is connected to the output terminal of the second delay driving circuit. When T1 and T2 are turned on, the current is injected from the first power supply VCC into the first power supply input terminal of the DC motor M, flows back to the ground through the second power supply input terminal of M, and the rotor of M rotates clockwise or counterclockwise; when T3 and T4 are turned on, the current is injected from the second power supply VCC into the second power supply input terminal of M, flows back to the ground through the first power supply input terminal of M, and the rotor of M rotates counterclockwise or clockwise.
[0022] In one embodiment, preferably, it further includes a motor control circuit, the motor stop rotation control terminal is connected to the motor control circuit input terminal, and the motor control circuit output terminal is connected through the first steering circuit and the second steering circuit respectively. Figure 2 As shown, preferably, the motor control circuit includes a fifteenth resistor, a second diode, and a third diode. Figure 2 In the figure, the output end of the motor control circuit is represented by CT2, the fifteenth resistor is represented by R8, the second diode is represented by D1, and the third diode is represented by D2. The gate of the first NMOS tube is connected to the positive electrode of the second diode, the negative electrode of the second diode is connected to the motor stop rotation control end through the fifteenth resistor, the gate of the second NMOS tube is connected to the positive electrode of the third diode, and the negative electrode of the third diode is connected to the motor stop rotation control end through the fifteenth resistor. The output end of the motor control circuit is the control end for stopping the rotation of the DC motor. In actual work, the resistance value of R8 is small enough. When the control level of CT2 is logic "0", the gate voltages of T2 and T4 are clamped at a sufficiently small voltage, and T2 and T4 cannot be turned on. Therefore, in this state, M cannot rotate. When the control level of CT2 is logic "1", since D1 and D2 are not reversely turned on, CT2 has no control effect on T2 and T4.
[0023] like Figure 2 As shown, preferably, the first delay driving circuit includes a third power supply, a third PMOS tube, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, and a first capacitor. Figure 2In the figure, the motor commutation control terminal is represented by CT1, the third power supply is represented by VDD, wherein VDD is an independent power supply, and its voltage is equal to the voltage of CT1 when the input is logic "1", and does not need to be the same as VCC, the third PMOS tube is represented by T5, the fifth resistor is represented by R6, the sixth resistor is represented by R7, the seventh resistor is represented by R12, the eighth resistor is represented by R13, the first capacitor is represented by C1, the third power supply is connected to the source of the third PMOS tube, the drain of the third PMOS tube is connected to the gate of the first NMOS tube through the fifth resistor, the sixth resistor and the first capacitor are connected in parallel between the gate and the source of the first NMOS tube, the gate of the third PMOS tube is connected to the third power supply through the seventh resistor, and the gate of the third PMOS tube is connected to the motor commutation control terminal through the eighth resistor. The motor commutation control terminal is the control terminal of the rotation direction of the DC motor.
[0024] like Figure 2 As shown, preferably, the second delay driving circuit includes a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a second capacitor, and a first diode. Figure 2 In the figure, the twelfth resistor is represented by R9, the thirteenth resistor is represented by R10, the fourteenth resistor is represented by R11, the second capacitor is represented by C2, the first diode is represented by D3, the gate of the second NMOS tube is connected to the positive electrode of the first diode through the twelfth resistor, the negative electrode of the first diode is connected to the motor commutation control terminal, the series branch of the twelfth resistor and the first diode is connected in parallel with the thirteenth resistor, and the fourteenth resistor and the second capacitor are connected in parallel between the gate and the source of the second NMOS tube. When the control level of CT2 is logic "1", if the control level of CT1 changes from logic "1" to logic "0", the gate of T4 discharges to the CT1 terminal through the resistor R9 and the diode D3. In actual work, the resistance value of R9 is small enough, the gate voltage of T4 will decrease rapidly, and T4 will be turned off. After T4 is turned off, T3 is also turned off. At the same time, under the appropriate resistance ratio of resistors R12 and R13, the gate-source voltage of PMOS T5 turns on T5. The third power supply VDD charges the gate of T2 through resistors R6, R7 and capacitor C1. In actual operation, if the resistance values of R6 and R7 are large enough and the capacitance value of C1 is large enough, the gate-source voltage of T2 will reach the turn-on voltage of T2 after a delay period, and turn on T2. The delay time is determined by the resistance values of R6 and R7 and the capacitance value of C1. Therefore, when the control level of CT1 changes from logic "1" to logic "0", T4 is turned off first and turns off T3, and then after a delay period, T2 is turned on and turns on T1 to complete the turn of M. Due to the delayed turn-on of T2, there will be no problem of short-term excessive current or even short circuit caused by current flowing from T3 to T2.
[0025] like Figure 2As shown, preferably, the steering shutdown circuit includes a third NMOS tube, a ninth resistor, a tenth resistor, and an eleventh resistor, the third NMOS tube is represented by T6, the ninth resistor is represented by R5, the tenth resistor is represented by R14, and the eleventh resistor is represented by R15. The drain of the third NMOS tube is connected to the gate of the first NMOS tube through the ninth resistor, the source of the third NMOS tube is grounded, the tenth resistor is connected between the source and the gate of the third NMOS tube, and the gate of the third NMOS tube is connected to the motor reversing control terminal through the eleventh resistor. When the control level of CT2 is logic "1", if the control level of CT1 changes from logic "0" to logic "1", by configuring appropriate resistors R15 and R14, T6 is quickly turned on, and the gate of T2 is discharged to the ground through the resistor R5. In actual work, the resistance value of R5 is small enough, the gate voltage of T2 will be quickly reduced, and T2 will be turned off. After T2 is turned off, T1 is also turned off. At this time, T5 is also turned off at the same time. At the same time, CT1 charges the gate of T4 through resistors R10, R11 and capacitor C2. In actual work, if the resistance values of R10 and R11 are large enough and the capacitance value of C2 is large enough, the gate-source voltage of T4 will reach the turn-on voltage of T4 after a delay period, and turn on T4. The delay time is determined by the resistance values of R10 and R11 and the capacitance value of C2. Therefore, when the control level of CT1 changes from logic "0" to logic "1", T2 is first turned off and T1 is turned off, and then after a delay period, T4 is turned on and T3 is turned on to complete the turn of M. Due to the delayed turn-on of T4, there will be no problem of short-term excessive current or even short circuit caused by the current flowing from T1 to T4. Due to the charging delay function of the first capacitor and the second capacitor, even if CT1 and CT2 are out of control, it will not cause excessive current or short circuit problems.
[0026] The present invention provides a DC motor commutation circuit, including a first steering circuit, a second steering circuit, a first delay drive circuit, a second delay drive circuit, and a steering shutoff circuit. The motor commutation control terminal is connected to the first delay drive circuit input terminal, the first delay drive circuit output terminal is connected to the DC motor through the first steering circuit, the motor commutation control terminal is connected to the second delay drive circuit input terminal, the second delay drive circuit output terminal is connected to the DC motor through the second steering circuit, the motor commutation control terminal is connected to the steering shutoff circuit input terminal, and the steering shutoff circuit output terminal is connected to the DC motor through the first steering circuit. The present invention utilizes the charging delay function of the first capacitor and the second capacitor, and when the power supply direction of the DC motor changes, the opening time of the new steering circuit is appropriately delayed, and the original steering circuit is quickly closed at the same time, to ensure that the steering circuit will not have a short-term current surge or even a short circuit problem, and only uses one motor commutation control terminal, with low cost, simple structure and high reliability.
[0027] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in any form. Any ordinary technician in the industry can smoothly implement the present invention as shown in the drawings and above. However, any equivalent changes, modifications and evolutions made by technicians familiar with the profession without departing from the scope of the technical solution of the present invention using the technical content disclosed above are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the technical solution of the present invention.
Claims
1. A DC motor commutation circuit, characterized in that: It includes a first steering circuit, a second steering circuit, a first delay drive circuit, a second delay drive circuit, and a steering shutoff circuit, wherein the motor reversing control terminal is connected to the input terminal of the first delay drive circuit, the output terminal of the first delay drive circuit is connected to the DC motor through the first steering circuit, the motor reversing control terminal is connected to the input terminal of the second delay drive circuit, the output terminal of the second delay drive circuit is connected to the DC motor through the second steering circuit, the motor reversing control terminal is connected to the input terminal of the steering shutoff circuit, and the output terminal of the steering shutoff circuit is connected to the DC motor through the first steering circuit; A DC motor commutation circuit also includes a motor control circuit, a motor stop rotation control terminal is connected to the input terminal of the motor control circuit, and an output terminal of the motor control circuit is connected through the first steering circuit and the second steering circuit respectively; The first steering circuit includes a first power supply, a first PMOS tube, a first NMOS tube, a first resistor, and a second resistor. The first power supply is connected to the source of the first PMOS tube, the drain of the first PMOS tube is connected to the first power input terminal of the DC motor, the gate of the first PMOS tube is connected to the first power supply through the first resistor, the first resistor is connected to the drain of the first NMOS tube through the second resistor, the drain of the first NMOS tube is connected to the second power input terminal of the DC motor, the source of the first NMOS tube is grounded, and the gate of the first NMOS tube is connected to the output terminal of the first delay driving circuit; The second steering circuit includes a second power supply, a second PMOS tube, a second NMOS tube, a third resistor, and a fourth resistor, the second power supply is connected to the source of the second PMOS tube, the drain of the second PMOS tube is connected to the second power supply input terminal of the DC motor, the gate of the second PMOS tube is connected to the second power supply through the third resistor, the third resistor is connected to the drain of the second NMOS tube through the fourth resistor, the drain of the second NMOS tube is connected to the first power supply input terminal of the DC motor, the source of the second NMOS tube is grounded, and the gate of the second NMOS tube is connected to the output terminal of the second delay driving circuit; The first delay driving circuit includes a third power supply, a third PMOS tube, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, and a first capacitor, wherein the third power supply is connected to the source of the third PMOS tube, the drain of the third PMOS tube is connected to the gate of the first NMOS tube through the fifth resistor, the sixth resistor and the first capacitor are connected in parallel between the gate and the source of the first NMOS tube, the gate of the third PMOS tube is connected to the third power supply through the seventh resistor, and the gate of the third PMOS tube is connected to the motor commutation control terminal through the eighth resistor; The steering shutdown circuit includes a third NMOS tube, a ninth resistor, a tenth resistor, and an eleventh resistor, the drain of the third NMOS tube is connected to the gate of the first NMOS tube through the ninth resistor, the source of the third NMOS tube is grounded, the tenth resistor is connected between the source and the gate of the third NMOS tube, and the gate of the third NMOS tube is connected to the motor reversing control terminal through the eleventh resistor; The second delay drive circuit includes a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a second capacitor, and a first diode. The gate of the second NMOS tube is connected to the positive electrode of the first diode through the twelfth resistor, the negative electrode of the first diode is connected to the motor commutation control end, the series branch of the twelfth resistor and the first diode is connected in parallel with the thirteenth resistor, and the fourteenth resistor and the second capacitor are connected in parallel between the gate and the source of the second NMOS tube.
2. A DC motor commutation circuit as claimed in claim 1, characterized in that: The motor control circuit includes a fifteenth resistor, a second diode, and a third diode. The gate of the first NMOS tube is connected to the anode of the second diode, the cathode of the second diode is connected to the motor stop rotation control terminal through the fifteenth resistor, the gate of the second NMOS tube is connected to the anode of the third diode, and the cathode of the third diode is connected to the motor stop rotation control terminal through the fifteenth resistor.