A braking circuit of a motor and an AGV control system

Abstract

The present application discloses a braking circuit of a motor and an AGV control system. The braking circuit includes: a pre-driving circuit, configured to receive a first control signal, process the first control signal to obtain a driving signal; an energy storage circuit, configured to receive a second control signal and generate a brake signal based on the second control signal; and a driving circuit, coupled to the pre-driving circuit, the energy storage circuit and the motor respectively, configured to provide the driving signal or the brake signal to the motor. In this way, the volume of the braking circuit can be reduced and the cost can be saved.

Description

Technical Field

[0001] This application relates to the technical field of electronic braking, and particularly to a braking circuit for a motor and an AGV control system. Background Art

[0002] In recent years, the use of automated guided vehicles (AGVs) has become increasingly popular. For safety reasons, in Europe, America and most countries, it is required that the driving wheels have a braking function. However, the software control scheme for driving the motor of the driving wheel has certain risks. For example, when the software runs away or freezes, the electric braking cannot be successfully realized. Therefore, at present, the vast majority of companies on the market adopt the mechanical braking (electromagnetic brake) scheme. However, this scheme has the characteristics of releasing when powered on and locking when powered off, and needs to be powered on all the time, resulting in more battery energy consumption. Moreover, when realizing the braking of a large torque load, the volume of the braking control structure is large and the hardware cost is high. Summary of the Invention

[0003] The main technical problem to be solved by this application is how to reduce the volume of the motor braking circuit and save costs.

[0004] To solve the above technical problem, a technical solution adopted by this application is: to provide a braking circuit for a motor. The braking circuit includes: a pre-driving circuit, configured to receive a first control signal, process the first control signal to obtain a driving signal; an energy storage circuit, configured to receive a second control signal and generate a braking signal based on the second control signal; and a driving circuit, coupled to the pre-driving circuit, the energy storage circuit and the motor respectively, configured to provide the driving signal or the braking signal to the motor.

[0005] To solve the above technical problem, a technical solution adopted by this application is: to provide an AGV control system. The AGV control system includes a controller and the above-mentioned braking circuit for the motor. The controller is connected to the braking circuit, and the braking circuit controls the motor to work or brake under the control of the controller.

[0006] The beneficial effect of the embodiment of this application is: The braking circuit of the motor in this application includes: a pre-driving circuit, configured to receive a first control signal, process the first control signal to obtain a driving signal; an energy storage circuit, configured to receive a second control signal and generate a braking signal based on the second control signal; and a driving circuit, coupled to the pre-driving circuit, the energy storage circuit and the motor respectively, configured to provide the driving signal or the braking signal to the motor. In this way, this application uses the energy storage circuit to provide the braking signal for the motor, and the driving circuit directly uses the braking signal to control the motor to brake. Since there is no need to use the motor itself to generate a large current torque to realize the braking function, therefore, there is no need to set components such as relays in the braking circuit, so the volume of the braking circuit can be reduced and the cost can be saved. Description of the Drawings

[0007] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0008] Figure 1 is a schematic structural diagram of the braking circuit of the motor;

[0009] Figure 2 is a schematic structural diagram of an embodiment of the braking circuit of the motor of the present application;

[0010] Figure 3 is a schematic structural diagram of another embodiment of the braking circuit of the motor of the present application;

[0011] Figure 4 is Figure 3 a schematic structural diagram of the circuit structure of the braking circuit of the embodiment;

[0012] Figure 5 is a schematic structural diagram of an embodiment of the AGV control system of the present application. Detailed implementation manners

[0013] The following will further describe the present application in detail in conjunction with the drawings and embodiments. It should be specifically pointed out that the following embodiments are only used to illustrate the present application, but do not limit the scope of the present application. Similarly, the following embodiments are only some embodiments of the present application rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope protected by the present application.

[0014] As Figure 1 shown, in the existing braking circuit, an external control signal is used to control the relay RY1 to pull in, so as to short-circuit the three-phase windings of the motor 1, and the braking function is realized by using the large current torque generated by the motor 1 itself to generate electricity. The disadvantage of this solution is that when a large braking current is required (generally, a large current is required to short-circuit the three-phase windings), the volume of the relay RY1 will be very large, resulting in a large volume of the braking circuit of the motor 1 and a high hardware cost.

[0015] To solve the above problems, the present application proposes a braking circuit for a motor, as Figure 2 shown, Figure 2It is a schematic structural diagram of an embodiment of the braking circuit of the motor in this application. The braking circuit 10 of this embodiment includes: a pre-drive circuit 110, an energy storage circuit 120, and a drive circuit 130. The drive circuit 130 is respectively coupled to the pre-drive circuit 110, the energy storage circuit 120, and the motor 20. Among them, the pre-drive circuit 110 is used to receive the first control signal and process the first control signal to obtain a drive signal. The energy storage circuit 120 is used to receive the second control signal and generate a brake signal based on the second control signal. The drive circuit 130 is used to provide a drive signal or a brake signal to the motor 20.

[0016] Among them, the motor 20 of this embodiment can be a DC motor or an AC motor, can also be a brushless motor or a brushed motor, and can also be a three-phase motor, etc., without specific limitation.

[0017] Among them, the main function of the pre-drive circuit 110 is to amplify the control signal of the MCU to a drive signal sufficient to drive the circuit 130. The pre-drive circuit 110 receives the first control signal and performs pre-processing such as filtering, amplifying, or transforming the first control signal.

[0018] The pre-drive circuit 110 of this embodiment can be a dedicated integrated chip, such as a three-phase brushless DC motor pre-driver, etc., which can drive a 6-channel N-channel power MOSFET three-phase bridge circuit. The pre-drive circuit 110 can also be composed of discrete circuits or devices, such as composed of an amplifier circuit and a filter circuit, etc.

[0019] Among them, the drive circuit 130 provides a drive signal for the motor 20 to drive the motor 20 to work, or provides a brake signal for the motor 20 to realize the braking of the motor 20. The drive circuit 130 can adopt a single-arm drive circuit to make the motor 20 rotate unidirectionally. The drive circuit 130 can also adopt a double-arm bridge drive circuit to make the control more flexible and be able to control the forward and reverse rotation of the motor 20. The drive circuit 130 can be a circuit for driving the motor 20 composed of power devices, and the power devices can be MOSFET or IGBT, etc.

[0020] This application can select the drive circuit 130 according to the type of the motor 20. For example, if the motor 20 is a DC motor, the drive of the DC motor is relatively simple. A power transistor can be selected to drive the DC motor, or a thyristor or a power MOS field effect transistor can be used to drive the DC motor.

[0021] The energy storage circuit 120 can include a capacitor or a battery, etc. Its main function is to control the conduction of the power device in the drive circuit 130 through the stored electric energy to provide a brake signal for the motor 20 when the power wheel (or other products) is powered off or works abnormally.

[0022] The energy storage element in the energy storage circuit 120 can be a capacitor, an inductor, or a series-parallel circuit of a capacitor and an inductor, etc.

[0023] Specifically, the pre-drive circuit 110 receives a first control signal, and the energy storage circuit 120 receives a second control signal; when the motor 20 is operating normally, the pre-drive circuit 110 preprocesses the first control signal to generate a drive signal, and outputs the drive signal to the drive circuit 130. The drive circuit 130 outputs the drive signal to the motor 20 to enable the motor 20 to operate normally. At this time, the energy storage circuit 120 stores electrical energy under the control of the second control signal; when the motor 20 needs to be braked, the energy storage circuit 120 generates a brake signal under the control of the second control signal, and outputs the brake signal to the drive circuit 130. The drive circuit 130 outputs the brake signal to the motor 20 to control the short circuit of the windings of the motor 20, so that the rotor of the motor 20 stops rotating, realizing the braking of the motor 20.

[0024] In an application scenario, the second control signal includes a high-level signal and a low-level signal. When the motor 20 is operating normally, the pre-drive circuit 110 preprocesses the first control signal to generate a drive signal, and outputs the drive signal to the drive circuit 130. The drive circuit 130 outputs the drive signal to the motor 20 to enable the motor 20 to operate normally. At this time, the energy storage circuit 120 receives the high-level signal and stores electrical energy under the control of the high-level signal; when the motor 20 needs to be braked, the energy storage circuit 120 receives the low-level signal, generates a brake signal under the control of the low-level signal, and outputs the brake signal to the drive circuit 130. The drive circuit 130 outputs the brake signal to the motor 20 to control the short circuit of the windings of the motor 20, so that the rotor of the motor 20 stops rotating, realizing the braking of the motor 20.

[0025] Different from the prior art, in this embodiment, the energy storage circuit 120 is used to provide a brake signal for the motor 20, and the drive circuit 130 directly uses this brake signal to control the braking of the motor 20. Since there is no need to use the motor 20 itself to generate a large current torque to achieve the braking function, therefore, in the braking circuit 10 of the motor 20, components such as relays do not need to be provided, so the volume of the braking circuit 10 can be reduced and the cost can be saved.

[0026] The present application further proposes a braking circuit for another embodiment of the motor, as Figure 3 shown, Figure 3 is a schematic structural diagram of another embodiment of the braking circuit of the motor of the present application; Figure 4 is Figure 3Schematic diagram of the circuit structure of the braking circuit in the embodiment. The braking circuit 10 in this embodiment includes: a pre-drive circuit 110, an energy storage circuit 120, a drive circuit 130, and a first protection circuit 140. The drive circuit 130 is respectively coupled to the energy storage circuit 120 and the motor 20. The pre-drive circuit 110 is coupled to the drive circuit 130 and the energy storage circuit 120 through the first protection circuit 140. Among them, the pre-drive circuit 110 receives a first control signal and processes the first control signal to obtain a drive signal. The energy storage circuit 120 receives a second control signal and generates a brake signal based on the second control signal. The drive circuit 130 is used to provide a drive signal or a brake signal to the motor 20. The first protection circuit 140 is used to disconnect the coupling between the pre-drive circuit 110 and the energy storage circuit 120 under the control of a third control signal.

[0027] Among them, the motor 20 in this embodiment can be a DC motor or an AC motor, can also be a brushless motor or a brushed motor, and can also be a three-phase motor, etc., without specific limitation.

[0028] Among them, the main function of the pre-drive circuit 110 is to amplify the control signal of the MCU to a drive signal sufficient to drive the circuit 130. The pre-drive circuit 110 receives the first control signal and performs preprocessing such as filtering, amplifying, or transforming the first control signal.

[0029] The pre-drive circuit 110 in this embodiment can be a dedicated integrated chip, such as a three-phase brushless DC motor pre-driver, etc., which can drive a 6-channel N-channel power MOSFET three-phase bridge circuit. The pre-drive circuit 110 can also be composed of discrete circuits or devices, such as composed of an amplification circuit and a filtering circuit, etc.

[0030] Specifically, when the motor 20 is working normally, the pre-drive circuit 110 receives the first control signal, preprocesses the first control signal to generate a drive signal, and outputs the drive signal to the first protection circuit 140. The first protection circuit 140 transmits the drive signal to the drive circuit 130 to enable the motor 20 to work normally. At this time, the energy storage circuit 120 stores electrical energy under the control of the second control signal. When the motor 20 needs to be braked, the energy storage circuit 120 generates a brake signal under the control of the second control signal and outputs the brake signal to the drive circuit 130. The drive circuit 130 outputs the brake signal to the motor 20 to control the short circuit of the windings of the motor 20, so that the rotor of the motor 20 stops rotating, realizing the braking of the motor 20. At this time, the first protection circuit 140 disconnects the coupling between the pre-drive circuit 110 and the energy storage circuit 120 under the control of the third control signal to prevent the energy storage circuit 120 from back-feeding the brake signal to the pre-drive circuit 110.

[0031] Among them, the third control signal is the same as the second control signal to simplify the circuit and control.

[0032] In an application scenario, the second control signal includes a high-level signal and a low-level signal. When the motor 20 is operating normally, the first protection circuit 140 receives the high-level signal and outputs a drive signal to the drive circuit 130 under the control of the high-level signal, so that the motor 20 operates normally. At this time, the energy storage circuit 120 receives the high-level signal and stores electrical energy under the control of the high-level signal; when the motor 20 needs to be braked, the energy storage circuit 120 receives the low-level signal, generates a brake signal under the control of the low-level signal, and outputs the brake signal to the drive circuit 130. The drive circuit 130 outputs the brake signal to the motor 20 to control the short circuit of the windings of the motor 20, so that the rotor of the motor 20 stops rotating, realizing the braking of the motor 20. At this time, the first protection circuit 140 receives the low-level signal and disconnects the coupling between the pre-drive circuit 110 and the energy storage circuit 120 under the control of the low-level signal, avoiding the energy storage circuit 120 from backfeeding the brake signal to the pre-drive circuit 110.

[0033] In other embodiments, the third control signal and the second control signal can be different, as long as the control of the high and low level signals of the two is synchronized, that is, the level signals are both high and both low.

[0034] Different from the prior art, in this embodiment, the energy storage circuit 120 is used to provide a brake signal for the motor 20, and the drive circuit 130 directly uses this brake signal to control the braking of the motor 20. Since there is no need to use the motor 20 itself to generate a large current torque to achieve the braking function, therefore, no components such as relays need to be provided in the braking circuit 10 of the motor 20. Therefore, the volume of the braking circuit 10 can be reduced and the cost can be saved.

[0035] Furthermore, when the motor 20 is operating normally, the first protection circuit 140 of this embodiment outputs a drive signal to the drive circuit 130 to make the motor 20 operate normally; and when the motor 20 is braked, the first protection circuit 140 disconnects the coupling between the pre-drive circuit 110 and the energy storage circuit 120, avoiding the energy storage circuit 120 from backfeeding the brake signal to the pre-drive circuit 110, and being able to prevent the pre-drive circuit 110 from being damaged (the voltage of the drive pin of the pre-drive circuit 110 cannot be higher than its supply voltage).

[0036] Optionally, the first protection circuit 140 of this embodiment includes: a first control circuit 141 and a selection circuit 142. The selection circuit 142 is respectively coupled to the first control circuit 141, the pre-drive circuit 110, the energy storage circuit 120, and the drive circuit 130; wherein, the first control circuit 141 generates a fourth control signal under the control of the third control signal; the selection circuit 142 is used to disconnect the signal transmission between the pre-drive circuit 110 and the energy storage circuit 120 under the control of the fourth control signal.

[0037] When the motor 20 is operating normally, the first control circuit 141 controls the selection circuit 142 to conduct through the fourth control signal, and outputs the drive signal to the drive circuit 130 through the selection circuit 142, so that the motor 20 operates normally; when the motor 20 is braked, the first control circuit 141 controls the selection circuit 142 to turn off through the fourth control signal, so as to disconnect the coupling between the pre-drive circuit 110 and the energy storage circuit 120, and avoid the energy storage circuit 120 from back-feeding the brake signal to the pre-drive circuit 110, which can prevent the pre-drive circuit 110 from being damaged.

[0038] The first protection circuit 140 implemented by the first control circuit 141 and the selection circuit 142 in this embodiment has a simple structure and is easy to control.

[0039] In other embodiments, the first protection circuit may also only include a selection circuit, and directly control the selection circuit by using the third control signal.

[0040] Specifically, the selection circuit 142 of this embodiment includes: a switching element OP1 and a first resistor R1. The first end 3 of the switching element OP1 is coupled to the pre-drive circuit 110, the second end 4 of the switching element OP1 is respectively coupled to the energy storage circuit 120 and the drive circuit 130, and one end of the first resistor R1 is coupled to the third end 2 of the switching element OP1.

[0041] Specifically, the first control circuit 141 of this embodiment includes: a first triode Q1, a second resistor R4 and a third resistor R7. The input end of the first triode Q1 is coupled to the other end of the first resistor R1, the control end of the first triode Q1 is respectively coupled to one end of the second resistor R4 and one end of the third resistor R7, the output end of the first triode Q1 and the other end of the third resistor R7 are grounded, and the other end of the second resistor R4 is connected to the third control signal.

[0042] The motor 20 of this embodiment is a three-phase motor, which includes three-phase windings 210; in order to realize the braking control of the three-phase windings of the motor 20, the selection circuit 142 of this embodiment includes: three switching elements OP1-OP3, three first resistors R1-R3; wherein, the first end 3 of the switching element OP2 is coupled to the pre-drive circuit 110, the second end 4 of the switching element OP2 is respectively coupled to the energy storage circuit 120 and the drive circuit 130, and one end of the first resistor R2 is coupled to the third end 2 of the switching element OP2; the first end 3 of the switching element OP3 is coupled to the pre-drive circuit 110, the second end 4 of the switching element OP3 is respectively coupled to the energy storage circuit 120 and the drive circuit 130, and one end of the first resistor R3 is coupled to the third end 2 of the switching element OP3.

[0043] The first control circuit 141 of this embodiment includes: three first triodes Q1 - Q3, three second resistors R4 - R7, and three third resistors R7 - R9; wherein, the input end of the first triode Q2 is coupled to the other end of the first resistor R2, the control end of the first triode Q2 is respectively coupled to one end of the second resistor R5 and one end of the third resistor R8, the output end of the first triode Q2 and the other end of the third resistor R8 are grounded, and the other end of the second resistor R5 is connected to the third control signal; the input end of the first triode Q3 is coupled to the other end of the first resistor R3, the control end of the first triode Q3 is respectively coupled to one end of the second resistor R6 and one end of the third resistor R9, the output end of the first triode Q3 and the other end of the third resistor R9 are grounded, and the other end of the second resistor R6 is connected to the third control signal.

[0044] Wherein, the switching elements OP1 - OP3 of this embodiment are optocouplers, achieving the purpose of electrical signal isolation through electro - optical - electrical conversion.

[0045] When the third terminal 2 of the switching element OP1 is connected to a high level, the light - emitting diode (not labeled in the figure) inside the switching element OP1 does not work, and the second terminal 4 of the switching element OP1 is also at a high level due to pull - up; when the third terminal 2 of the switching element OP1 is connected to a low level, the light - emitting diode inside the switching element OP1 works, causing the triode (not labeled in the figure) inside the switching element OP1 to conduct, and the second terminal 4 of the switching element OP1 outputs a low level.

[0046] In other embodiments, the selection circuit can also be other data selectors or other switching elements, such as a single - pole double - throw switch, or a selection circuit composed of diodes, power transistors, comparators, etc.

[0047] In other embodiments, other power transistors, etc. can also be used to replace the triodes in the first control circuit.

[0048] Optionally, the energy storage circuit 120 of this embodiment includes: a storage circuit 121 and a second control circuit 122; wherein, the storage circuit 121 is used for storing electrical energy; the second control circuit 122 is respectively coupled to the storage circuit 121, the second terminal 4 of the switching element OP1, and the drive circuit 130, and is used for converting electrical energy into a brake signal under the control of the second control signal and outputting the brake signal to the drive circuit 130.

[0049] When the motor 20 is operating normally, the storage circuit 121 receives a high-level signal and stores electrical energy under the control of the high-level signal. At the same time, the drive circuit 130 outputs a drive signal to the motor 20 to enable the motor 20 to operate normally. When the motor 20 needs to be braked, the energy storage circuit 120 receives a low-level signal, generates a brake signal under the control of the low-level signal, and outputs the brake signal to the drive circuit 130. The drive circuit 130 outputs the brake signal to the motor 20 to control the short circuit of the windings of the motor 20, so that the rotor of the motor 20 stops rotating, realizing the braking of the motor 20.

[0050] Among them, the storage circuit 120 of this embodiment includes a first diode D1, a zener diode Z, a fourth resistor R10, and a capacitor C. The cathode of the first diode D1 is connected to the voltage, the anode of the first diode D1 is coupled to one end of the fourth resistor R10, the other end of the fourth resistor R10 is respectively coupled to the anode of the zener diode Z and one end of the capacitor C, and the cathode of the zener diode Z and the other end of the capacitor C are grounded.

[0051] In other embodiments, a series-parallel circuit of an inductor, a capacitor, and a capacitor can also be used to replace the capacitor C.

[0052] The storage circuit 120 may specifically include a capacitor or a battery, etc. It is mainly used to control the conduction of the power device in the drive circuit through the stored electrical energy to provide a brake signal for the motor in the case of power failure or abnormal operation of the power wheel (or other products).

[0053] Among them, the second control circuit 122 of this embodiment includes a fifth resistor R11, a sixth resistor R12, a seventh resistor R13, and a second triode Q4. One end of the fifth resistor R11 is coupled to the other end of the fourth resistor R10, the other end of the fifth resistor R11 is coupled to the input end of the second triode Q4, the first end of the sixth resistor R12 is connected to the second control signal, the other end of the sixth resistor R12 is respectively coupled to one end of the seventh resistor R13 and the control end of the second triode Q4, and the other end of the seventh resistor R13 and the output end of the second triode Q4 are grounded..

[0054] Optionally, the energy storage circuit 120 of this embodiment further includes: a second protection circuit 123, which is respectively coupled to the second control circuit 122, the second end 4 of the switch OP1, and the drive circuit 130, and is used to prevent the drive signal from being output to the second control circuit 122

[0055] Among them, the second protection circuit 123 of this embodiment includes a second diode D2. The cathode of the second diode D2 is coupled to the other end of the fifth resistor R11, and the anode of the second diode D2 is coupled to the second end 4 of the switch OP1.

[0056] As can be seen from the above analysis, the motor 20 in this embodiment is a three-phase motor, which includes three-phase windings 210; to achieve braking control of the three-phase windings of the motor 20, the second protection circuit 123 in this embodiment includes three second diodes D2-D4. The cathode of the second diode D3 is coupled to the other end of the fifth resistor R11, and the anode of the second diode D3 is coupled to the second terminal 4 of the switching element OP2; the cathode of the second diode D4 is coupled to the other end of the fifth resistor R11, and the anode of the second diode D4 is coupled to the second terminal 4 of the switching element OP3.

[0057] When the motor 20 is operating normally, the pre-drive circuit 110 transmits a drive signal to the first protection circuit 140, and the first protection circuit 140 is coupled to the energy storage circuit 120. In this embodiment, by providing the second protection circuit 123 in the energy storage circuit 120, it is possible to prevent the first protection circuit 140 from outputting the drive circuit to the energy storage circuit 120 and avoid damaging the energy storage circuit 120.

[0058] In other embodiments, a unidirectional conduction element or circuit can also be used to replace the second diode, such as a thyristor (SCR), etc.

[0059] Optionally, the drive circuit 130 in this embodiment includes a first power transistor Q5. The control terminal of the first power transistor Q5 is respectively coupled to the anode of the second diode D2 and the second terminal 4 of the switching element OP1. The output terminal of the first power transistor Q5 is coupled to a winding 210 of the motor 20, and the input terminal of the first power transistor Q5 is grounded.

[0060] To achieve braking control of the three-phase windings of the motor 20, the drive circuit 130 in this embodiment includes three first power transistors Q5-Q7. The control terminal of the first power transistor Q6 is respectively coupled to the anode of the second diode D3 and the second terminal 4 of the switching element OP2. The output terminal of the first power transistor Q6 is coupled to another winding 210 of the motor 20, and the input terminal of the first power transistor Q6 is grounded; the control terminal of the first power transistor Q7 is respectively coupled to the anode of the second diode D4 and the second terminal 4 of the switching element OP3. The output terminal of the first power transistor Q7 is coupled to yet another winding 210 of the motor 20, and the input terminal of the first power transistor Q7 is grounded.

[0061] The three second diodes D2-D5, the three switching elements OP1-OP3, and the three first power transistors Q5-Q7 are arranged in one-to-one correspondence, and the three first power transistors Q5-Q7 are coupled to the three-phase windings 210 of the motor 20 in one-to-one correspondence.

[0062] Further, the drive circuit 130 of this embodiment further includes second power transistors Q8 - Q10. The control terminal of the second power transistor Q8 is connected to a control signal. The input terminal of the second power transistor Q8 is connected to the output terminal of the first power transistor Q5, and the output terminal of the second power transistor Q8 is connected to a voltage. The control terminal of the second power transistor Q9 is connected to a control signal. The input terminal of the second power transistor Q9 is connected to the output terminal of the first power transistor Q6, and the output terminal of the second power transistor Q9 is connected to a voltage. The control terminal of the second power transistor Q10 is connected to a control signal. The input terminal of the second power transistor Q10 is connected to the output terminal of the first power transistor Q7, and the output terminal of the second power transistor Q10 is connected to a voltage.

[0063] The above-mentioned power transistors in this embodiment are IGBTs; in other embodiments, power transistors such as MOSFETs can also be used to replace IGBTs.

[0064] Among them, the drive circuit 130 of this embodiment is a double-arm bridge drive circuit, which is more flexible in control; in other embodiments, a single-arm drive circuit or the like can also be used for the drive circuit.

[0065] In other embodiments, the drive circuit can also be selected according to the type of the motor. For example, if the motor is a DC motor, the drive of the DC motor is relatively simple. A power transistor can be selected to drive the DC motor, or a thyristor or a power MOS field effect transistor can be used to drive the DC motor.

[0066] In an application scenario, when the motor 20 is operating normally, the pre-drive circuit 110 receives a first control signal and preprocesses the first control signal to generate drive signals GLA_P, GLB_P, and GLC_P, and outputs the drive signals GLA_P, GLB_P, and GLC_P to the switching elements OP1 - OP3 respectively. At this time, the first triodes Q1 - Q3 receive high-level signals and the first triodes Q1 - Q3 conduct. At this time, the levels of the third terminals 2 of the switching elements OP1 - OP3 are pulled to low level by the first triodes Q1 - Q3 respectively, that is, the third terminals 2 of the switching elements OP1 - OP3 are connected to low-level signals, and the light-emitting diodes inside the switching elements OP1 - OP3 work, causing the triodes inside the switching elements OP1 - OP3 to conduct, and outputting the drive signals GLA_P, GLB_P, and GLC_P to the first power transistors Q5 - Q7 respectively. The first power transistors Q5 - Q7 conduct to output the drive signals GLA_P, GLB_P, and GLC_P to the motor 20 to make the motor 20 operate normally. At this time, the control terminal of the second triode Q4 is connected to a high-level signal, the second triode Q4 conducts, the second diodes D2 - D4 are reversely cut off, the capacitor C is charged, and is controlled by the zener diode Z to be near the drive voltage at the control terminal of the second triode Q4; and the second diodes D2 - D4 are reversely cut off, and the drive signals will not be back-fed to the storage circuit 120.

[0067] In another application scenario, when the motor 20 needs to be braked, the first triodes Q1 - Q3 receive a low - level signal and turn off; at this time, the level of the third terminal 2 of the switch elements OP1 - OP3 is high - level, and the light - emitting diodes inside the switch elements OP1 - OP3 do not work, resulting in the triodes inside the switch elements OP1 - OP3 turning off, and the drive signals GLA_P, GLB_P, and GLC_P are not output to the first power transistors Q5 - Q7; at this time, the control terminal of the second triode Q4 is connected to a low - level signal, the second triode Q4 turns off, the second diodes D2 - D4 conduct, the capacitor C discharges, generating a brake signal, and transmitting the brake signal to the drive signal 130; the first power transistors Q5 - Q7 conduct and output the brake signal to the motor 20, controlling the windings of the motor 20 to be short - circuited, so that the rotor of the motor 20 stops rotating, realizing the braking of the motor 20.

[0068] The braking circuit of the present application can be used in products such as power wheel modules.

[0069] The present application further proposes an AGV control system, as Figure 5 shown, the AGV control system 50 of this embodiment includes a controller 510 and a braking circuit 520. The controller 510 is connected to the braking circuit 520, and the braking circuit 520 controls the operation or braking of the motor 20 under the control of the controller 510.

[0070] Furthermore, the AGV control system 50 of this embodiment includes a main control panel provided on the AGV. The main control panel includes a controller 510, a power conversion module, a communication module for signal transmission, a motor drive module, etc.; among them, the braking circuit 520 is provided on the motor drive module.

[0071] The braking circuit 520 of this embodiment is similar to the above - mentioned braking circuit 10 and will not be elaborated here.

[0072] Different from the prior art, the braking circuit of the motor in the present application includes: a pre - drive circuit for receiving a first control signal and processing the first control signal to obtain a drive signal; an energy - storage circuit for receiving a second control signal and generating a brake signal based on the second control signal; a drive circuit respectively coupled to the pre - drive circuit, the energy - storage circuit, and the motor, for providing a drive signal or a brake signal to the motor. In this way, the present application uses an energy - storage circuit to provide a brake signal for the motor, and the drive circuit directly uses this brake signal to control the braking of the motor. Since there is no need to use the motor itself to generate a large - current torque to achieve the braking function, there is no need to set components such as relays in the braking circuit. Therefore, the volume of the braking circuit can be reduced, and costs can be saved.

[0073] Further, when the motor is operating normally, the first protection circuit in this embodiment conducts the coupling between the pre-drive circuit and the energy storage circuit and outputs a drive signal to the drive circuit to enable the motor to operate normally; and when the motor is braked, the first protection circuit disconnects the coupling between the pre-drive circuit and the energy storage circuit, preventing the energy storage circuit from back-feeding the brake signal to the pre-drive circuit, and thus avoiding damage to the pre-drive circuit.

[0074] Further, when the motor is operating normally, by providing a second protection circuit in the energy storage circuit, it is possible to prevent the first protection circuit from transmitting the drive circuit to the energy storage circuit and avoid damaging the energy storage circuit.

[0075] The above are only the embodiments of the present application, and do not limit the patent scope of the present application. Any equivalent mechanism or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present application.

Claims

1. A braking circuit for a motor, characterized in that, Comprising: A pre-drive circuit, configured to receive a first control signal, process the first control signal to obtain a drive signal; An energy storage circuit, configured to receive a second control signal and generate a brake signal based on the second control signal; A drive circuit, coupled to the pre-drive circuit, the energy storage circuit, and the motor respectively, configured to provide the drive signal or the brake signal to the motor; Wherein, the braking circuit further includes a first protection circuit, the pre-drive circuit is coupled to the drive circuit and the energy storage circuit through the first protection circuit, and the first protection circuit disconnects the coupling between the pre-drive circuit and the energy storage circuit under the control of a third control signal.

2. The braking circuit according to claim 1, wherein The first protection circuit includes: A first control circuit, configured to generate a fourth control signal under the control of the third control signal; A selection circuit, coupled to the first control circuit, the pre-drive circuit, the energy storage circuit, and the drive circuit respectively, configured to disconnect the coupling between the pre-drive circuit and the energy storage circuit under the control of the fourth control signal.

3. The braking circuit according to claim 2, wherein The selection circuit includes: A switching element, with a first end coupled to the pre-drive circuit, and a second end coupled to the energy storage circuit and the drive circuit respectively; A first resistor, with one end coupled to a third end of the switching element; The first control circuit includes a first triode, a second resistor, and a third resistor. The input end of the first triode is coupled to the other end of the first resistor, the control end of the first triode is coupled to one end of the second resistor and one end of the third resistor respectively, the output end of the first triode and the other end of the third resistor are grounded, and the other end of the second resistor is connected to the third control signal.

4. The braking circuit according to claim 3, wherein The energy storage circuit includes: A storage circuit, configured to store electrical energy; A second control circuit, coupled to the storage circuit, the second end of the switching element, and the drive circuit respectively, configured to convert the electrical energy into the brake signal under the control of the second control signal.

5. The braking circuit according to claim 4, characterized in that, The energy storage circuit further includes a second protection circuit, coupled to the second control circuit, the second end of the switching element, and the drive circuit respectively, configured to prevent the drive signal from being transmitted to the second control circuit.

6. The braking circuit according to claim 5, characterized in that, The storage circuit includes a first diode, a zener diode, a fourth resistor, and a capacitor. The anode of the first diode is connected to a voltage, the cathode of the first diode is coupled to one end of the fourth resistor, the other end of the fourth resistor is coupled to the cathode of the zener diode and one end of the capacitor respectively, and the anode of the zener diode and the other end of the capacitor are grounded; The second control circuit includes a fifth resistor, a sixth resistor, a seventh resistor, and a second triode. One end of the fifth resistor is coupled to the other end of the fourth resistor, the other end of the fifth resistor is coupled to the input end of the second triode, the first end of the sixth resistor is connected to the second control signal, the other end of the sixth resistor is coupled to one end of the seventh resistor and the control end of the second triode respectively, and the other end of the seventh resistor and the output end of the second triode are grounded; The second protection circuit includes a second diode, the anode of which is coupled to the other end of the fifth resistor, and the cathode of which is coupled to the second end of the switching element.

7. The braking circuit according to claim 6, characterized in that, The drive circuit includes a first power transistor, the control terminal of which is respectively coupled to the cathode of the second diode and the second end of the switching element, the output terminal of which is coupled to the winding of the motor, and the input terminal of which is grounded.

8. The braking circuit according to claim 7, wherein, The first protection circuit includes three of the switching elements, the second protection circuit includes three of the second diodes, the drive circuit includes three of the power transistors, the three second diodes, the three switching elements and the three power transistors are arranged in one-to-one correspondence, and the three power transistors are coupled to the three-phase windings of the motor in one-to-one correspondence.

9. The braking circuit according to claim 7, wherein, The drive circuit further includes a second power transistor, the control terminal of which is connected to a fifth control signal, the input terminal of which is coupled to the output terminal of the first power transistor, and the output terminal of which is connected to a voltage.

10. An AGV control system, characterized in that, It includes a controller and a braking circuit of the motor according to any one of claims 1 to 9, the controller is connected to the braking circuit, and the braking circuit controls the operation or braking of the motor under the control of the controller.

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