Motor recoil voltage absorption circuit and motor control system

Abstract

The utility model discloses a motor recoil voltage absorption circuit and a motor control system, and the circuit comprises a voltage detection module which is connected between a positive electrode power supply end and a negative electrode power supply end, and is used for outputting a conduction signal when the voltage between the positive electrode power supply end and the negative electrode power supply end is greater than a threshold voltage; the control end of the electric energy absorption control module is electrically connected with the output end of the voltage detection module, and the electric energy absorption control module is used for controlling conduction of the electric energy absorption control module according to the conduction signal; and the electric energy absorption module and the electric energy absorption control module are connected in series between the positive electrode power supply end and the negative electrode power supply end, and the electric energy absorption module is used for forming a conductive path with the electric energy absorption control module when the electric energy absorption control module is switched on. The circuit can accurately control the opening and closing of the electric energy absorption module, reliably absorb the recoil voltage, and prevent the control circuit of the motor from being damaged.

Description

Technical Field

[0001] The utility model relates to the technical field of motors, and in particular to a motor recoil voltage absorption circuit and a motor control system. Background Art

[0002] For battery-powered devices, especially lithium-ion battery-powered bicycles, scooters, electric wheelchairs, etc., when the charging function is turned off in a low temperature environment or when the battery is fully charged, if downhill or braking conditions occur, the recoil voltage of the motor in the bicycle, scooter or electric wheelchair will increase sharply, which can easily cause damage to the control board of the device and affect the normal operation of the device. Utility Model Content

[0003] The utility model provides a motor recoil voltage absorption circuit and a motor control system, which can accurately control the opening and closing of an electric energy absorption module, reliably absorb the recoil voltage of the motor, and avoid damaging the control circuit.

[0004] According to one aspect of the utility model, a motor recoil voltage absorption circuit is provided, comprising:

[0005] A voltage detection module, connected between the positive power supply terminal and the negative power supply terminal, the voltage detection module is used to output a conduction signal when the voltage between the positive power supply terminal and the negative power supply terminal is greater than a threshold voltage;

[0006] An electric energy absorption control module, wherein a control end of the electric energy absorption control module is electrically connected to an output end of the voltage detection module, and the electric energy absorption control module is used to control the electric energy absorption control module to be turned on according to the conduction signal;

[0007] An electric energy absorption module, wherein the first end of the electric energy absorption module is electrically connected to the positive power supply end, the second end of the electric energy absorption module is electrically connected to the first end of the electric energy absorption control module, and the second end of the electric energy absorption control module is electrically connected to the negative power supply end, and the electric energy absorption module is used to form a conductive path with the electric energy absorption control module when the electric energy absorption control module is turned on.

[0008] Optionally, the electric energy absorption control module includes:

[0009] a thirteenth resistor, a first end of the thirteenth resistor being electrically connected to the output end of the voltage detection module, and a second end of the thirteenth resistor being grounded;

[0010] a fifth switch tube, wherein the first end of the fifth switch tube serves as the first end of the electric energy absorption control module, the second end of the fifth switch tube serves as the second end of the electric energy absorption control module, the control end of the fifth switch tube is electrically connected to the first end of the thirteenth resistor, and the control end of the fifth switch tube serves as the control end of the electric energy absorption control module;

[0011] The motor recoil voltage absorption circuit also includes a control voltage setting module;

[0012] The input end of the control voltage setting module is electrically connected to the output end of the voltage detection module, and the output end of the control voltage setting module is electrically connected to the control end of the electric energy absorption control module. The control voltage setting module is used to generate and output a saturation zone control voltage at the output end of the control voltage setting module according to the conduction signal to control the fifth switch tube to be in the saturation zone when it is turned on.

[0013] Optionally, the control voltage setting module includes:

[0014] a first resistor, wherein a first end of the first resistor serves as an input end of the control voltage setting module;

[0015] a second resistor, a first end of the second resistor being electrically connected to a second end of the first resistor, and a second end of the second resistor being grounded;

[0016] a third resistor, a first end of the third resistor being connected to the saturation region control voltage;

[0017] a fourth resistor, wherein a first end of the fourth resistor is electrically connected to a second end of the third resistor, and a second end of the fourth resistor is grounded;

[0018] an operational amplifier, wherein a first input terminal of the operational amplifier is electrically connected to a second terminal of the first resistor, a second input terminal of the operational amplifier is electrically connected to a second terminal of the third resistor, an output terminal of the operational amplifier serves as an output terminal of the control voltage setting module, a first power supply terminal of the operational amplifier is connected to the saturation region control voltage, and a second power supply terminal of the operational amplifier is grounded;

[0019] a fifth resistor, wherein a first end of the fifth resistor is electrically connected to the first input end of the operational amplifier, and a second end of the fifth resistor is electrically connected to the output end of the operational amplifier;

[0020] A first capacitor, wherein a first end of the first capacitor is electrically connected to the first input end of the operational amplifier, and a second end of the first capacitor is electrically connected to the output end of the operational amplifier.

[0021] Optionally, the motor recoil voltage absorption circuit further includes a voltage reduction module;

[0022] The input end of the step-down module is electrically connected to the output end of the voltage detection module, and the output end of the step-down module is electrically connected to the first power supply end of the operational amplifier and the first end of the third resistor. The step-down module is used to convert the voltage output by the output end of the voltage detection module into the saturation region control voltage, wherein the saturation region control voltage is less than the voltage output by the output end of the voltage detection module.

[0023] Optionally, the voltage reduction module includes:

[0024] a sixth resistor, wherein a first end of the sixth resistor serves as an input end of the voltage-reducing module;

[0025] A first voltage regulator tube, wherein a first end of the first voltage regulator tube is electrically connected to a second end of the sixth resistor, and a second end of the first voltage regulator tube is grounded;

[0026] a seventh resistor, a first end of the seventh resistor being electrically connected to the first end of the sixth resistor;

[0027] a first switch tube, wherein a first end of the first switch tube is electrically connected to a second end of the seventh resistor, and a control end of the first switch tube is electrically connected to a second end of the sixth resistor;

[0028] an eighth resistor, a first end of the eighth resistor being electrically connected to the first end of the sixth resistor;

[0029] A second switch tube, wherein the first end of the second switch tube is electrically connected to the second end of the eighth resistor, the second end of the second switch tube serves as the output end of the buck module, and the control end of the second switch tube is electrically connected to the second end of the first switch tube.

[0030] Optionally, the motor recoil voltage absorption circuit further includes: an anti-reverse connection module;

[0031] The positive terminal of the anti-reverse connection module is electrically connected to the second end of the electric energy absorption module, and the negative terminal of the anti-reverse connection module is electrically connected to the first end of the electric energy absorption control module;

[0032] The anti-reverse connection module is used to disconnect when the positive power supply terminal is connected to a first potential and the negative power supply terminal is connected to a second potential; wherein the first potential is lower than the second potential.

[0033] Optionally, the voltage detection module includes:

[0034] a ninth resistor, wherein a first end of the ninth resistor is electrically connected to the positive power supply end;

[0035] A second voltage-stabilizing tube, wherein a first end of the second voltage-stabilizing tube is electrically connected to a second end of the ninth resistor;

[0036] a tenth resistor, wherein a first end of the tenth resistor is electrically connected to the second end of the second voltage regulator tube, and a second end of the tenth resistor is electrically connected to the negative power supply end;

[0037] a third switch tube, wherein a first end of the third switch tube is electrically connected to the positive power supply end, and a second end of the third switch tube serves as an output end of the voltage detection module;

[0038] an eleventh resistor, a first end of the eleventh resistor being electrically connected to the positive power supply end, and a second end of the eleventh resistor being electrically connected to the control end of the third switch tube;

[0039] a twelfth resistor, a first end of the twelfth resistor being electrically connected to the control end of the third switch tube;

[0040] A fourth switch tube, wherein a first end of the fourth switch tube is electrically connected to the second end of the twelfth resistor, a second end of the fourth switch tube is electrically connected to the negative power supply end, and a control end of the fourth switch tube is electrically connected to the second end of the second voltage regulator tube.

[0041] Optionally, the voltage detection module further includes a third voltage regulator tube;

[0042] The first end of the third voltage regulator tube is electrically connected to the control end of the fourth switch tube, and the second end of the third voltage regulator tube is electrically connected to the second end of the fourth switch tube.

[0043] Optionally, the electric energy absorption module includes: at least one fifteenth resistor, a first end of the fifteenth resistor serving as the first end of the electric energy absorption module, and a second end of the fifteenth resistor serving as the second end of the electric energy absorption module.

[0044] According to another aspect of the utility model, a motor control system is provided, comprising a battery module, a motor, a motor control circuit and the motor recoil voltage absorption circuit described in any one of the above items;

[0045] The positive terminal of the battery module is connected to the positive terminal of the motor control circuit, the negative terminal of the battery module is connected to the negative terminal of the motor control circuit, and the motor control circuit is connected to the motor;

[0046] The positive power supply terminal is the positive terminal of the battery module, and the negative power supply terminal is the negative terminal of the battery module, or the positive power supply terminal is the positive terminal of the motor control circuit, and the negative power supply terminal is the negative terminal of the motor control circuit.

[0047] The technical solution of the embodiment of the utility model is to obtain the voltage between the positive power supply terminal and the negative power supply terminal through the voltage detection module, and when the voltage between the positive power supply terminal and the negative power supply terminal is greater than the threshold voltage, the voltage detection module is used to control the power absorption control module to conduct, thereby forming a conductive loop between the positive power supply terminal, the power absorption module, the power absorption control module and the negative power supply terminal, and current flows through the power absorption module to consume the voltage of the positive power supply terminal and the negative power supply terminal, thereby avoiding damage to the control circuit of the motor caused by excessive recoil voltage of the motor. When the voltage between the positive power supply terminal and the negative power supply terminal is less than the threshold voltage, the power absorption control module is turned off, so that no current flows through the power absorption module, no power is consumed, and the power utilization rate is improved.

[0048] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present utility model, nor are they intended to limit the scope of the present utility model. Other features of the present utility model will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0050] Figure 1 A principle block diagram of a motor recoil voltage absorption circuit provided by an embodiment of the utility model;

[0051] Figure 2 A principle block diagram of another motor recoil voltage absorption circuit provided by an embodiment of the utility model;

[0052] Figure 3 A circuit diagram of a motor recoil voltage absorption circuit provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0053] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0054] It should be noted that the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the utility model described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0055] Figure 1 A schematic diagram of a motor recoil voltage absorption circuit provided by the present utility model, referring to Figure 1 , the circuit comprises:

[0056] A voltage detection module 1 is connected between the positive power supply terminal J11 and the negative power supply terminal J12, and the voltage detection module 1 is used to output a conduction signal when the voltage between the positive power supply terminal J11 and the negative power supply terminal J12 is greater than a threshold voltage;

[0057] An electric energy absorption control module 2, wherein the control end of the electric energy absorption control module 2 is electrically connected to the output end of the voltage detection module 1, and the electric energy absorption control module 2 is used to control the conduction of the electric energy absorption control module 2 according to the conduction signal;

[0058] The electric energy absorption module 3, the first end of the electric energy absorption module 3 is electrically connected to the positive power supply terminal J11, the second end of the electric energy absorption module 3 is electrically connected to the first end of the electric energy absorption control module 2, and the second end of the electric energy absorption control module 2 is electrically connected to the negative power supply terminal J12. The electric energy absorption module 3 is used to form a conductive path with the electric energy absorption control module 2 when the electric energy absorption control module 2 is turned on, so as to absorb the electric energy between the positive power supply terminal J11 and the negative power supply terminal J12.

[0059] The threshold voltage is the minimum voltage value set to control the electric energy absorption module 3 to absorb the voltage of the positive power supply terminal J11 and the negative power supply terminal J12. The on signal is a signal to control the electric energy absorption control module 2 to be turned on, and the off signal is a signal to control the electric energy absorption control module 2 to be turned off. The voltage detection module 1 is used to output a turn-on signal when the voltage between the positive power supply terminal J11 and the negative power supply terminal J12 is greater than the threshold voltage, and control the electric energy absorption control module 2 to be turned on through the turn-on signal, so that the branch where the electric energy absorption module 3 and the electric energy absorption control module 2 are located is turned on, so that the absorption module 3 consumes electric energy in the circuit. The voltage detection module 1 is also used to output a turn-off signal when the voltage between the positive power supply terminal J11 and the negative power supply terminal J12 is greater than the threshold voltage, and control the electric energy absorption control module 2 to be turned off, so that the branch where the electric energy absorption module 3 and the electric energy absorption control module 2 are located is turned off, and the electric energy absorption module 3 has no current and does not consume electric energy in the circuit. In an optional embodiment, the voltage detection module 1 may include a comparator that outputs a turn-on signal when the voltage between the positive power supply terminal J11 and the negative power supply terminal J12 is greater than a threshold voltage, and outputs a turn-off signal when the voltage between the positive power supply terminal J11 and the negative power supply terminal J12 is less than the threshold voltage.

[0060] The electric energy absorption control module 2 is used to turn on in response to the on signal, and is also used to turn off in response to the off signal. In an optional embodiment, the electric energy absorption control module 2 may include a switch unit, which is turned on in response to the on signal, thereby turning on the branch where the electric energy absorption module 3 is located, and is also used to turn off in response to the off signal, thereby closing the branch where the electric energy absorption module 3 is located.

[0061] The electric energy absorption module 3 and the electric energy absorption control module 2 are connected in series between the positive power supply terminal J11 and the negative power supply terminal J12. When the electric energy absorption control module 2 is turned on, a closed conductive loop is formed between the positive power supply terminal J11, the electric energy absorption module 3, the electric energy absorption control module 2 and the negative power supply terminal J12, and current flows through the electric energy absorption module 3, consuming electric energy in the circuit, thereby reducing the impact of the kickback voltage. Among them, the electric energy absorption module 3 can be a capacitor, or can also be other devices that can consume electric energy, which is not specifically limited here.

[0062] The technical solution of the embodiment of the utility model is to obtain the voltage between the positive power supply terminal and the negative power supply terminal through the voltage detection module, and when the voltage between the positive power supply terminal and the negative power supply terminal is greater than the threshold voltage, the voltage detection module is used to control the power absorption control module to conduct, thereby forming a conductive loop between the positive power supply terminal, the power absorption module, the power absorption control module and the negative power supply terminal, and current flows through the power absorption module to consume the voltage between the positive power supply terminal and the negative power supply terminal, thereby avoiding damage to the control circuit of the motor caused by excessive recoil voltage of the motor. When the voltage between the positive power supply terminal and the negative power supply terminal is less than the threshold voltage, the power absorption control module is turned off, so that no current flows through the power absorption module, no power is consumed, energy waste is avoided, and energy utilization is improved.

[0063] Figure 2 Another motor recoil voltage absorption circuit provided by the present utility model is shown in FIG. Figure 2 Optionally, the electric energy absorption control module 2 includes:

[0064] A thirteenth resistor R13, a first end of the thirteenth resistor R13 is electrically connected to the output end of the voltage detection module 1, and a second end of the thirteenth resistor R13 is grounded GND;

[0065] a fifth switch tube Q5, wherein the first end of the fifth switch tube Q5 serves as the first end of the electric energy absorption control module 2, the second end of the fifth switch tube Q5 serves as the second end of the electric energy absorption control module 2, the control end of the fifth switch tube Q5 is electrically connected to the first end of the thirteenth resistor R13, and the control end of the fifth switch tube Q5 serves as the control end of the electric energy absorption control module 2;

[0066] The motor kickback voltage absorption circuit also includes a control voltage setting module 4;

[0067] The input end of the control voltage setting module 4 is electrically connected to the output end of the voltage detection module 1, and the output end of the control voltage setting module 4 is electrically connected to the control end of the power absorption control module 2. The control voltage setting module 4 is used to generate and output a saturation region control voltage at the output end of the power absorption control module 2 according to the conduction signal to control the fifth switch tube Q5 to be in the saturation region when it is turned on. Optionally, the negative power supply terminal J12 is grounded GND.

[0068] The fifth switch tube is a MOS tube, such as an NMOS tube. The working state of the MOS tube includes a saturation region and a linear region. In the linear region, the impedance of the MOS tube is proportional to the gate-source voltage difference of the MOS tube. In the saturation region, the impedance of the MOS tube remains unchanged and can be recorded as zero. If the conduction signal output by the voltage detection module 1 is directly connected to the control end (the control end of the fifth switch tube Q5) of the electric energy absorption control module 2, the fifth switch tube Q5 may be operated in the linear region. In the linear region, the impedance of the fifth switch tube Q5 may be large, thereby greatly reducing the electric energy consumed by the electric energy absorption module 3, and the temperature of the fifth switch tube Q5 may also rise, damaging the fifth switch tube Q5. Therefore, it is necessary to connect the control voltage setting module 4 between the output end of the voltage detection module 1 and the control end of the electric energy absorption control module 2 to ensure that the saturation region control voltage output by the control voltage setting module 4 can control the fifth switch tube Q5 to operate in the saturation region. Optionally, the electric energy absorption control module 2 further includes a fourteenth resistor R14. When the motor kickback voltage absorption circuit includes a control voltage setting module 4, the first end of the thirteenth resistor R13 is electrically connected to the output end of the voltage detection module 1 through the fourteenth resistor R14 and the control voltage setting module 4 in sequence. The saturation region control voltage output by the control voltage setting module 4 is divided by the fourteenth resistor R14 and the thirteenth resistor R13, and the divided voltage value of the thirteenth resistor R13 is output to the fifth switch tube Q5. Therefore, the magnitude of the saturation region control voltage and the resistance values ​​of the fourteenth resistor R14 and the thirteenth resistor R13 are set in advance, and the divided voltage value of the thirteenth resistor R13 is limited to the voltage range for controlling the fifth switch tube Q5 to operate in the saturation region.

[0069] Continue to refer Figure 2 , Optionally, the motor recoil voltage absorption circuit further includes: an anti-reverse connection module 6;

[0070] The positive terminal of the anti-reverse connection module 6 is electrically connected to the second end of the electric energy absorption module 3, and the negative terminal of the anti-reverse connection module 6 is electrically connected to the first end of the electric energy absorption control module 2;

[0071] The anti-reverse connection module 6 is used to disconnect when the positive power supply terminal J11 is connected to a first potential and the negative power supply terminal J12 is connected to a second potential; wherein the first potential is lower than the second potential.

[0072] The positive power supply terminal J11 is used to connect to the positive voltage in the control circuit where the motor is located, and the negative power supply terminal J12 is used to connect to the negative voltage in the control circuit where the motor is located. An anti-reverse connection module 6 is provided. When the voltages of the positive power supply terminal J11 and the negative power supply terminal J12 are reversed, the branch where the power absorption module 3 and the power absorption control module 2 are located is not conductive, thereby preventing the power absorption module 3 from consuming the voltage between the positive power supply terminal J11 and the negative power supply terminal J12 when the voltages of the positive power supply terminal J11 and the negative power supply terminal J12 are reversed.

[0073] Continue to refer Figure 2 Optionally, the motor recoil voltage absorption circuit further includes: a temperature control switch QT, the temperature control switch is connected between the positive power supply terminal J11 and the voltage detection module 1, and the temperature control switch QT is used to disconnect when the temperature of the motor recoil voltage absorption circuit is greater than a preset temperature, so as to disconnect the connection between the positive power supply terminal J11 and the voltage detection module 1, and avoid the entire circuit from over-temperature operation. The temperature control switch QT is also used to close when the temperature of the motor recoil voltage absorption circuit is greater than a preset temperature, so as to connect the positive power supply terminal J11 and the first end of the voltage detection module 1.

[0074] Figure 3 A circuit diagram of a motor recoil voltage absorption circuit provided by an embodiment of the utility model, referring to Figure 3 Optionally, the voltage detection module 1 includes:

[0075] A ninth resistor R9, wherein a first end of the ninth resistor R9 is electrically connected to the positive power supply terminal J11;

[0076] A second voltage regulator tube Z2, wherein a first end of the second voltage regulator tube Z2 is electrically connected to a second end of a ninth resistor R9;

[0077] a tenth resistor R10, wherein a first end of the tenth resistor R10 is electrically connected to a second end of the second voltage regulator tube Z2, and a second end of the tenth resistor R10 is electrically connected to a negative power supply terminal J12;

[0078] A third switch tube Q3, wherein a first end of the third switch tube Q3 is electrically connected to the positive power supply terminal J11, and a second end of the third switch tube Q3 serves as an output end of the voltage detection module 1;

[0079] an eleventh resistor R11, wherein a first end of the eleventh resistor R11 is electrically connected to the positive power supply terminal J11, and a second end of the eleventh resistor R11 is electrically connected to the control end of the third switch tube Q3;

[0080] a twelfth resistor R12, wherein a first end of the twelfth resistor R12 is electrically connected to a control end of the third switch tube Q3;

[0081] The fourth switch tube Q4, the first end of the fourth switch tube is electrically connected to the second end of the twelfth resistor R12, the second end of the fourth switch tube Q4 is electrically connected to the negative power supply terminal J12, and the control end of the fourth switch tube Q4 is electrically connected to the second end of the second voltage regulator tube Z2.

[0082] The second voltage regulator tube Z2 is a Zener diode with an avalanche voltage (reverse breakdown voltage), the fourth switch tube Q4 can be an NMOS tube, and the third switch tube Q3 can be a PNP transistor. When a kickback voltage appears in the circuit and causes the voltage in the circuit to rise sharply, the voltage between the positive power supply terminal J11 and the negative power supply terminal J12 is greater than the avalanche voltage of the second voltage regulator tube Z2, and the second voltage regulator tube Z2 is turned on. The fourth switch tube Q4 is an NMOS tube. After the second voltage regulator tube Z2 is turned on, the voltage difference between the control terminal and the second terminal of the fourth switch tube Q4 is the voltage across the tenth resistor R10, which is greater than the threshold voltage of the fourth switch tube Q4, thereby turning on the fourth switch tube Q4. After the fourth switch tube Q4 is turned on, the branch where the eleventh resistor R11 and the twelfth resistor R12 are located is turned on, and current flows through the twelfth resistor R12, that is, there is current at the control end of the third switch tube Q3, and the third switch tube Q3 is turned on. After the third switch tube Q3 is turned on, the output end of the voltage detection module 1, that is, the third switch tube Q3 outputs a conduction signal, wherein the conduction signal is the potential of the positive power supply terminal J11.

[0083] Furthermore, the voltage detection module 1 also includes a third voltage regulator tube Z3;

[0084] A first end of the third voltage regulator tube Z3 is electrically connected to a control end of the fourth switch tube Q4 , and a second end of the third voltage regulator tube Z3 is electrically connected to a second end of the fourth switch tube Q4 .

[0085] The voltage difference between the control end and the second end of the fourth switch tube Q4 needs to be set within a certain voltage range. If the voltage difference is too large, the fourth switch tube Q4 will be damaged. Therefore, the third voltage regulator tube Z3 is connected between the control end and the second end of the fourth switch tube Q4, and the third voltage regulator tube Z3 is connected in parallel with the tenth resistor R10. When the voltage between the positive power supply end J11 and the negative power supply end J12 is too large, the voltage across the tenth resistor R10 increases. When the avalanche voltage of the third voltage regulator tube Z3 is reached, the third voltage regulator tube Z3 is reversely broken down. After the third voltage regulator tube Z3 is turned on, the voltage difference between the control end and the second end of the fourth switch tube Q4 is controlled to a relatively small stable value. Even if the voltage between the positive power supply end J11 and the negative power supply end J12 fluctuates, the voltage across the third voltage regulator tube Z3 remains substantially unchanged, thereby preventing the fourth switch tube Q4 from being damaged due to a relatively large voltage, thereby improving the reliability of the circuit.

[0086] The output end of the voltage detection module 1 can be connected to the control end of the electric energy absorption control module 2 through at least one resistor, but the fifth switch tube Q5 is a MOS tube, and there may be a certain voltage range that causes the fifth switch tube Q5 to work in the linear region, resulting in a decrease in the electric energy absorbed by the absorption module 3. Therefore, in this embodiment, a control voltage setting module 4 is connected between the output end of the voltage detection module 1 and the control end of the electric energy absorption control module 2.

[0087] Continue to refer Figure 3 Optionally, the control voltage setting module 4 includes:

[0088] A first resistor R1, wherein a first end of the first resistor R1 serves as an input end of the control voltage setting module 4;

[0089] A second resistor R2, a first end of the second resistor R1 is electrically connected to a second end of the first resistor R1, and a second end of the second resistor R2 is grounded to GND;

[0090] A third resistor R3, a first end of the third resistor R3 is connected to the saturation region control voltage VDD;

[0091] a fourth resistor R4, wherein a first end of the fourth resistor R4 is electrically connected to a second end of the third resistor R3, and a second end of the fourth resistor R4 is grounded to GND;

[0092] An operational amplifier U1, wherein a first input terminal of the operational amplifier U1 is electrically connected to a second terminal of the first resistor R1, a second input terminal of the operational amplifier U1 is electrically connected to a second terminal of the third resistor R3, an output terminal of the operational amplifier U1 serves as an output terminal of the control voltage setting module 4, a first power terminal of the operational amplifier U1 is connected to a saturation region control voltage VDD, and a second power terminal of the operational amplifier U1 is grounded GND;

[0093] a fifth resistor R5, wherein a first end of the fifth resistor R5 is electrically connected to the first input end of the operational amplifier U1, and a second end of the fifth resistor R5 is electrically connected to the output end of the operational amplifier U1;

[0094] The first capacitor C1 has a first end electrically connected to the first input end of the operational amplifier U1 , and a second end electrically connected to the output end of the operational amplifier U1 .

[0095] Optionally, the control voltage setting module 4 also includes a second capacitor C2, a first end of the second capacitor C2 is electrically connected to the second end of the third resistor R3, a second end of the second capacitor C2 is grounded GND, and the second capacitor C2 is used to filter the voltage input to the second input end of the operational amplifier U1.

[0096] The voltage of the positive power supply terminal J11 is divided by the first resistor R1 and the second resistor R2, and the voltage divided value on the second resistor R2 is input to the first input terminal of the operational amplifier U1. The saturation region control voltage VDD is divided by the third resistor R3 and the fourth resistor R4, and the voltage divided value on the fourth resistor R4 is input to the second input terminal of the operational amplifier U1. When the voltage divided value on the second resistor R2 is greater than the voltage divided value on the fourth resistor R4, the output terminal of the operational amplifier U1 outputs the saturation region control voltage VDD to the electric energy absorption control module 2. When the voltage divided value on the second resistor R2 is less than the voltage divided value on the fourth resistor R4, the output terminal of the operational amplifier U1 outputs the ground potential such as 0V voltage to the electric energy absorption control module 2. Because the control voltage setting module 4 only outputs OV voltage or the saturation region control voltage VDD, the control end of the fourth switch tube Q5 is stably connected to the saturation region control voltage VDD or its divided voltage. Figure 3 As shown, the saturation region control voltage VDD outputted from the output end of the operational amplifier U1 is divided by the fourteenth resistor R14 and the thirteenth resistor R13 and then inputted to the control end of the fifth switch tube Q5. Therefore, by setting the magnitude of the saturation region control voltage VDD and the resistance values ​​of the fourteenth resistor R14 and the thirteenth resistor R13, the control end of the fifth switch tube Q5 can be made to operate in the saturation region when receiving the divided voltage value of the saturation region control voltage VDD, so that the impedance of the fifth switch tube Q5 is zero, and the electric energy absorption module 3 consumes the voltage between the positive power supply terminal J11 and the negative power supply terminal J12 to the maximum extent.

[0097] Based on the above embodiments, continue to refer to Figure 3 , Optionally, the motor recoil voltage absorption circuit also includes a step-down module 5;

[0098] The input end of the step-down module 5 is electrically connected to the output end of the voltage detection module 1, and the output end of the step-down module 5 is electrically connected to the first power supply end of the operational amplifier U1 and the first end of the third resistor R3. The step-down module 5 is used to convert the voltage output by the output end of the voltage detection module 1 into a saturation region control voltage VDD, wherein the saturation region control voltage VDD is less than the voltage output by the output end of the voltage detection module 1.

[0099] The step-down module 5 can be a step-down circuit such as a buck circuit, or other circuits capable of achieving a step-down function, which is not specifically limited in this embodiment. When there is a kickback voltage in the circuit and the kickback voltage is too high, the voltage outputted by the output end of the voltage detection module 1 will be too large, and the voltage outputted by the voltage detection module 1 is reduced by the step-down module 5 and then outputted to the control voltage setting module 4, providing the control voltage setting module 4 with a saturation region control voltage.

[0100] Continue to refer Figure 3 Optionally, the step-down module 5 includes:

[0101] A sixth resistor R6, a first end of the sixth resistor R6 serves as an input end of the voltage reduction module 5 and is electrically connected to an output end of the voltage detection module 1;

[0102] A first voltage regulator tube Z1, wherein a first end of the first voltage regulator tube Z1 is electrically connected to a second end of the sixth resistor R6, and a second end of the first voltage regulator tube Z1 is grounded GND;

[0103] a seventh resistor R7, wherein a first end of the seventh resistor R7 is electrically connected to a first end of the sixth resistor R6;

[0104] A first switch tube Q1, wherein a first end of the first switch tube Q1 is electrically connected to a second end of a seventh resistor R7, and a control end of the first switch tube Q1 is electrically connected to a second end of a sixth resistor R6;

[0105] an eighth resistor R8, a first end of the eighth resistor R8 being electrically connected to a first end of the sixth resistor R6;

[0106] The second switch tube Q2, the first end of the second switch tube Q2 is electrically connected to the second end of the eighth resistor R8, the second end of the second switch tube Q2 serves as the output end of the step-down module 5, and the control end of the second switch tube Q2 is electrically connected to the second end of the first switch tube Q1. Optionally, the step-down module 5 further includes a fourth voltage regulator tube Z4 and a third capacitor C3, the first end of the fourth voltage regulator tube Z4 is electrically connected to the second end of the second switch tube Q2, the second end of the fourth voltage regulator tube Z4 is grounded GND, the first end of the third capacitor C3 is electrically connected to the second end of the second switch tube Q2, and the second end of the third capacitor C3 is grounded GND.

[0107] Optionally, the first switch tube Q1 and the second switch tube Q2 are both NPN transistors. After the voltage between the positive power supply terminal J11 and the negative power supply terminal J12 rises sharply due to the kickback voltage, causing the second voltage regulator tube Z2 to be turned on, the third switch tube Q3 is also turned on. The voltage across the first voltage regulator tube Z1 is the voltage difference between the positive power supply terminal J11 and the ground potential, which is greater than the avalanche voltage of the first voltage regulator tube Z1, so that the first voltage regulator tube Z1 is turned on. After the first voltage regulator tube Z1 is turned on, the first switch tube Q1 is turned on, and after the first switch tube Q1 is turned on, the second switch tube Q2 is turned on, and finally the voltage at the second end of the second switch tube Q2 is equal to the avalanche voltage of the first voltage regulator tube Z1 minus the conduction voltage drop of the first switch tube Q1, and then minus the conduction voltage drop of the second switch tube Q2. For example, if the avalanche voltage is 12V, the on-state voltage drop of the first switch tube Q1 and the on-state voltage drop of the second switch tube Q2 are both 0.6V, then the saturation region control voltage outputted from the output end of the buck module 5 is equal to 10.8V.

[0108] Continue to refer Figure 3Optionally, the electric energy absorption module 3 includes: at least one fifteenth resistor R15, the first end of the fifteenth resistor R15 serves as the first end of the electric energy absorption module 3, and the second end of the fifteenth resistor R15 serves as the second end of the electric energy absorption module 3.

[0109] The electric energy absorption module 3 may include only one fifteenth resistor R15 connected between the first end and the second end of the electric energy absorption module 3, and may also include at least two fifteenth resistors R15, each of which is connected in parallel, and each fifteenth resistor R15 is connected between the first end and the second end of the electric energy absorption module 3. After the electric energy absorption control module 2 is turned on, the branch connected in series between the fifteenth resistor R15 and the electric energy absorption control module 2 is turned on, and current flows through the fifteenth resistor R15 to consume electric energy.

[0110] Continue to refer Figure 3 Optionally, the anti-reverse connection module 6 includes at least one first diode D1, the positive terminal of the first diode D1 is electrically connected to the second end of the electric energy absorption module 3, and the negative terminal of the first diode D1 is electrically connected to the first end of the electric energy absorption control module 2.

[0111] The fifth switch tube Q5 is an NMOS tube, and the NMOS tube has a parasitic diode D3. If the voltages of the positive power supply terminal J11 and the negative power supply terminal J12 are reversed, the parasitic diode D3 is turned on, and the current flows from the negative power supply terminal J12, the parasitic diode D3 and the power absorption module 3 to the positive power supply terminal J11, causing the absorption module 3 to consume power and waste energy. At least one first diode D1 is connected between the second end of the power absorption module 3 and the first end of the power absorption control module 2, so that the power absorption module 3 can be prevented from consuming power when the voltages of the positive power supply terminal J11 and the negative power supply terminal J12 are reversed.

[0112] Continue to refer Figure 3 Optionally, the motor kickback voltage absorption circuit further includes a sixteenth resistor R16, a seventeenth resistor R17, an indicator device LD and a second diode D2. The second diode D2, the indicator device LD, the sixteenth resistor R16 and the seventeenth resistor R17 are sequentially connected in series between the positive power supply terminal J11 and the negative power supply terminal J12. The indicator device LD is a light emitting diode, which is used to emit light when the voltage of the positive power supply terminal J11 and the negative power supply terminal J12 is reversed or the power absorption module 3 in the circuit consumes power.

[0113] The embodiment of the utility model further provides a motor control system, including a battery module, a motor, a motor control circuit, and the motor recoil voltage absorption circuit in any of the above embodiments;

[0114] The positive terminal of the battery module is connected to the positive terminal of the motor control circuit, the negative terminal of the battery module is connected to the negative terminal of the motor control circuit, and the motor control circuit is connected to the motor;

[0115] The positive power supply terminal is the positive terminal of the battery module, and the negative power supply terminal is the negative terminal of the battery module, or the positive power supply terminal is the positive terminal of the motor control circuit, and the negative power supply terminal is the negative terminal of the motor control circuit.

[0116] The battery module is used to power the motor control circuit, and the motor control circuit is used to control the operation of the motor. When the motor generates a recoil voltage and the recoil voltage rises sharply, the motor recoil voltage absorption circuit is turned on, and the recoil voltage is consumed by the electric energy absorption module, thereby reducing the voltage in the system. When the motor is working normally and the voltage is within the normal voltage working range, there is no recoil voltage, the motor recoil voltage absorption circuit does not work, and the energy of the battery module is not consumed, thereby improving energy utilization. The motor control system also has the beneficial effects of the motor recoil voltage absorption circuit, which will not be repeated here.

[0117] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0118] The above specific implementations do not constitute a limitation on the protection scope of the present utility model. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A motor kickback voltage absorption circuit, characterized in that: include: A voltage detection module, connected between the positive power supply terminal and the negative power supply terminal, the voltage detection module is used to output a conduction signal when the voltage between the positive power supply terminal and the negative power supply terminal is greater than a threshold voltage; An electric energy absorption control module, wherein a control end of the electric energy absorption control module is electrically connected to an output end of the voltage detection module, and the electric energy absorption control module is used to control the electric energy absorption control module to be turned on according to the conduction signal; An electric energy absorption module, wherein the first end of the electric energy absorption module is electrically connected to the positive power supply end, the second end of the electric energy absorption module is electrically connected to the first end of the electric energy absorption control module, and the second end of the electric energy absorption control module is electrically connected to the negative power supply end, and the electric energy absorption module is used to form a conductive path with the electric energy absorption control module when the electric energy absorption control module is turned on.

2. The motor kickback voltage absorption circuit according to claim 1, characterized in that: The electric energy absorption control module comprises: a thirteenth resistor, a first end of the thirteenth resistor being electrically connected to the output end of the voltage detection module, and a second end of the thirteenth resistor being grounded; a fifth switch tube, wherein the first end of the fifth switch tube serves as the first end of the electric energy absorption control module, the second end of the fifth switch tube serves as the second end of the electric energy absorption control module, the control end of the fifth switch tube is electrically connected to the first end of the thirteenth resistor, and the control end of the fifth switch tube serves as the control end of the electric energy absorption control module; The motor recoil voltage absorption circuit also includes a control voltage setting module; The input end of the control voltage setting module is electrically connected to the output end of the voltage detection module, and the output end of the control voltage setting module is electrically connected to the control end of the electric energy absorption control module. The control voltage setting module is used to generate and output a saturation zone control voltage at the output end of the control voltage setting module according to the conduction signal to control the fifth switch tube to be in the saturation zone when it is turned on.

3. The motor kickback voltage absorption circuit according to claim 2, characterized in that: The control voltage setting module comprises: a first resistor, wherein a first end of the first resistor serves as an input end of the control voltage setting module; a second resistor, a first end of the second resistor being electrically connected to a second end of the first resistor, and a second end of the second resistor being grounded; a third resistor, a first end of the third resistor being connected to the saturation region control voltage; a fourth resistor, wherein a first end of the fourth resistor is electrically connected to a second end of the third resistor, and a second end of the fourth resistor is grounded; an operational amplifier, wherein a first input terminal of the operational amplifier is electrically connected to a second terminal of the first resistor, a second input terminal of the operational amplifier is electrically connected to a second terminal of the third resistor, an output terminal of the operational amplifier serves as an output terminal of the control voltage setting module, a first power supply terminal of the operational amplifier is connected to the saturation region control voltage, and a second power supply terminal of the operational amplifier is grounded; a fifth resistor, wherein a first end of the fifth resistor is electrically connected to the first input end of the operational amplifier, and a second end of the fifth resistor is electrically connected to the output end of the operational amplifier; A first capacitor, wherein a first end of the first capacitor is electrically connected to the first input end of the operational amplifier, and a second end of the first capacitor is electrically connected to the output end of the operational amplifier.

4. The motor kickback voltage absorption circuit according to claim 3, characterized in that: Also included is a step-down module; The input end of the step-down module is electrically connected to the output end of the voltage detection module, and the output end of the step-down module is electrically connected to the first power supply end of the operational amplifier and the first end of the third resistor. The step-down module is used to convert the voltage output by the output end of the voltage detection module into the saturation region control voltage, wherein the saturation region control voltage is less than the voltage output by the output end of the voltage detection module.

5. The motor kickback voltage absorption circuit according to claim 4, characterized in that: The step-down module comprises: a sixth resistor, wherein a first end of the sixth resistor serves as an input end of the voltage-reducing module; A first voltage regulator tube, wherein a first end of the first voltage regulator tube is electrically connected to a second end of the sixth resistor, and a second end of the first voltage regulator tube is grounded; a seventh resistor, a first end of the seventh resistor being electrically connected to the first end of the sixth resistor; a first switch tube, wherein a first end of the first switch tube is electrically connected to a second end of the seventh resistor, and a control end of the first switch tube is electrically connected to a second end of the sixth resistor; an eighth resistor, a first end of the eighth resistor being electrically connected to the first end of the sixth resistor; A second switch tube, wherein the first end of the second switch tube is electrically connected to the second end of the eighth resistor, the second end of the second switch tube serves as the output end of the buck module, and the control end of the second switch tube is electrically connected to the second end of the first switch tube.

6. The motor kickback voltage absorption circuit according to claim 1, characterized in that: Also includes: Anti-reverse connection module; The positive terminal of the anti-reverse connection module is electrically connected to the second end of the electric energy absorption module, and the negative terminal of the anti-reverse connection module is electrically connected to the first end of the electric energy absorption control module; The anti-reverse connection module is used to disconnect when the positive power supply terminal is connected to a first potential and the negative power supply terminal is connected to a second potential; wherein the first potential is lower than the second potential.

7. The motor kickback voltage absorption circuit according to any one of claims 1 to 6, characterized in that: The voltage detection module comprises: a ninth resistor, wherein a first end of the ninth resistor is electrically connected to the positive power supply end; A second voltage-stabilizing tube, wherein a first end of the second voltage-stabilizing tube is electrically connected to a second end of the ninth resistor; a tenth resistor, wherein a first end of the tenth resistor is electrically connected to the second end of the second voltage regulator tube, and a second end of the tenth resistor is electrically connected to the negative power supply end; a third switch tube, wherein a first end of the third switch tube is electrically connected to the positive power supply end, and a second end of the third switch tube serves as an output end of the voltage detection module; an eleventh resistor, a first end of the eleventh resistor being electrically connected to the positive power supply end, and a second end of the eleventh resistor being electrically connected to the control end of the third switch tube; a twelfth resistor, a first end of the twelfth resistor being electrically connected to the control end of the third switch tube; A fourth switch tube, wherein a first end of the fourth switch tube is electrically connected to the second end of the twelfth resistor, a second end of the fourth switch tube is electrically connected to the negative power supply end, and a control end of the fourth switch tube is electrically connected to the second end of the second voltage regulator tube.

8. The motor kickback voltage absorption circuit according to claim 7, characterized in that: The voltage detection module also includes a third voltage regulator tube; The first end of the third voltage regulator tube is electrically connected to the control end of the fourth switch tube, and the second end of the third voltage regulator tube is electrically connected to the second end of the fourth switch tube.

9. The motor kickback voltage absorption circuit according to any one of claims 1 to 6, characterized in that: The electric energy absorption module includes: at least one fifteenth resistor, a first end of the fifteenth resistor serves as a first end of the electric energy absorption module, and a second end of the fifteenth resistor serves as a second end of the electric energy absorption module.

10. A motor control system, characterized in that: It comprises a battery module, a motor, a motor control circuit and the motor recoil voltage absorption circuit according to any one of claims 1 to 9; The positive terminal of the battery module is connected to the positive terminal of the motor control circuit, the negative terminal of the battery module is connected to the negative terminal of the motor control circuit, and the motor control circuit is connected to the motor; The positive power supply terminal is the positive terminal of the battery module, and the negative power supply terminal is the negative terminal of the battery module, or the positive power supply terminal is the positive terminal of the motor control circuit, and the negative power supply terminal is the negative terminal of the motor control circuit.

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