Motor temperature compensation circuit and electronic equipment

Abstract

The invention provides a motor temperature compensation circuit and electronic equipment, and the motor temperature compensation circuit employs a micro-control unit to collect the circuit temperature values of two constant current source modules through successively conducting the two constant current source modules, and due to the compensation provided by the two constant current source modules, the temperature values of the two constant current source modules are reduced. Therefore, the influence of systematic errors of the operational amplifier circuit, the constant current source circuit and the temperature sensor in the circuit is eliminated, the motor temperature acquisition and analysis precision is improved, and the problem that the existing scheme does not consider the deviation of the resistor, the operational amplifier and the constant current source generation circuit in the circuit is solved. And the accuracy of motor temperature detection is low.

Description

Technical Field

[0001] The present application relates to the technical field of motor temperature detection, and in particular to a motor temperature compensation circuit and electronic equipment. Background Art

[0002] During the operation of electric vehicles, the motor will generate heat. If the temperature is not controlled accurately or timely, the motor will be demagnetized and its life will be shortened due to overheating, which may even cause safety problems for the electric drive system.

[0003] At present, most of them use the traditional motor temperature sampling circuit, which connects the temperature sensor in series and parallel with the resistor to form a voltage divider circuit. When the sensor resistance changes, the resistance of the series and parallel circuit changes accordingly, and the motor temperature is calculated by the voltage divider value. Furthermore, in order to improve the accuracy of the acquisition circuit, a constant current source circuit will be added. A constant current flows through the temperature sensor. When the sensor resistance changes, a changing voltage value is output, thereby calculating a more accurate motor temperature.

[0004] However, currently, commonly used temperature sensors include NTC, PT100, PT1000, etc. The above acquisition circuit is mostly suitable for situations where the corresponding changes in temperature and resistance are small. Even a small acquisition error such as PT100 will cause a large motor temperature acquisition error, so higher requirements are put forward for the acquisition accuracy of the temperature acquisition circuit. In particular, there will be deviations in the internal resistance of the circuit, operational amplifier, constant current source generation circuit, etc., which will cause a large deviation in the motor temperature analysis.

[0005] That is, the existing solution does not take into account the deviations in the internal resistance, operational amplifier, and constant current source generating circuit of the circuit, resulting in low accuracy of motor temperature detection. Summary of the invention

[0006] The main purpose of the present application is to provide a motor temperature compensation circuit and electronic device to at least solve the problem that the existing solutions do not take into account the deviations in the internal resistance, operational amplifier, and constant current source generating circuit of the circuit, resulting in low accuracy of motor temperature detection.

[0007] In order to achieve the above object, according to one aspect of the present application, a motor temperature compensation circuit is provided, and the motor temperature compensation circuit includes:

[0008] a temperature sensor, wherein a first end of the temperature sensor is electrically connected to a voltage source, the temperature sensor is located inside the motor and is used to detect the temperature of the motor,

[0009] A differential amplifier module, comprising a first input terminal, a second input terminal and an output terminal, wherein the first input terminal of the differential amplifier module is electrically connected to the first terminal of the temperature sensor, and the second input terminal of the differential amplifier module is electrically connected to the second terminal of the temperature sensor;

[0010] A voltage drop bearing module having a first end, a second end and a third end, wherein the third end of the voltage drop bearing module is electrically connected to the second end of the temperature sensor;

[0011] A voltage stabilizing module, wherein a power supply end of the voltage stabilizing module is electrically connected to the voltage source and the first end of the voltage drop bearing module respectively;

[0012] Two constant current source modules, namely a first constant current source module and a second constant current source module, the conduction end of the first constant current source module is electrically connected to the output end of the voltage stabilizing module, the second end of the voltage drop bearing module and the conduction end of the second constant current source module respectively, and the first constant current source module and the second constant current source module are used to compensate for the temperature of the motor detected by the temperature sensor;

[0013] A microcontroller unit, wherein a first control end of the microcontroller unit is electrically connected to a control end of the first constant current source module, a second control end of the microcontroller unit is electrically connected to a control end of the second constant current source module, and a voltage collection end of the microcontroller unit is electrically connected to an output end of the differential amplifier module.

[0014] Optionally, the differential amplifier module includes a first operational amplifier resistor module, a second operational amplifier resistor module, a third operational amplifier resistor module, a fourth operational amplifier resistor module and a first operational amplifier, the first end of the first operational amplifier resistor module is electrically connected to the first end of the temperature sensor, the first end of the third operational amplifier resistor module is electrically connected to the second end of the temperature sensor, the in-phase input end of the first operational amplifier is electrically connected to the second end of the first operational amplifier resistor module and the second end of the second operational amplifier resistor module, respectively, the inverting input end of the first operational amplifier is electrically connected to the second end of the third operational amplifier resistor module and the first end of the fourth operational amplifier resistor module, respectively, the output end of the first operational amplifier is electrically connected to the second end of the fourth operational amplifier resistor module and the voltage collection end of the micro control unit, and the first end of the second operational amplifier resistor module is grounded.

[0015] Optionally, the first constant current source module includes a first power switch device and a first constant current source resistor module, the second constant current source module includes a second power switch device and a second constant current source resistor module, the drain of the first power switch device is electrically connected to the second end of the first constant current source resistor module, the drain of the second power switch device is electrically connected to the second end of the second constant current source resistor module, the gate of the first power switch device is electrically connected to the first control end of the micro control unit, the gate of the second power switch device is electrically connected to the second control end of the micro control unit, the first end of the first constant current source resistor module and the first end of the second constant current source resistor module are respectively electrically connected to the output end of the voltage stabilizing module, and the input end of the voltage stabilizing module, the source of the first power switch device and the source of the second power switch device are respectively grounded.

[0016] Optionally, the micro control unit is used to perform the following steps:

[0017] Acquiring a first collection voltage when only the first power switch device is turned on;

[0018] When only the second power switch device is turned on, obtaining a second collection voltage;

[0019] according to

[0020] Determining the resistance value of the temperature sensor;

[0021] Among them, RM represents the temperature sensor, R3 is the third op amp resistor module, R4 is the fourth op amp resistor module, R5 is the first voltage divider resistor module, R6 is the second voltage divider resistor module, R7 is the third voltage divider resistor module, R8 is the first constant current source resistor module, R9 is the second constant current source resistor module, Vo1 is the first acquisition voltage, Vo2 is the second acquisition voltage, VCC is the voltage source, VU1 is the voltage between the first end of the temperature sensor and the first voltage divider resistor module when only the first power switch device is turned on, the first voltage divider resistor module is electrically connected between the voltage source and the first end of the temperature sensor, the first end of the second voltage divider resistor module is electrically connected to the first end of the temperature sensor, the second end of the second voltage divider resistor module is electrically connected to the second end of the temperature sensor, and the third voltage divider resistor module is electrically connected between the second end of the second voltage divider resistor module and the third end of the voltage drop bearing module.

[0022] Optionally, the motor temperature compensation circuit also includes an isolation voltage stabilization module, the non-phase input terminal of the isolation voltage stabilization module is electrically connected to the first end of the temperature sensor, and the inverting input terminal of the isolation voltage stabilization module is electrically connected to the output terminal of the isolation voltage stabilization module and the second input terminal of the differential amplifier module.

[0023] Optionally, the motor temperature compensation circuit further includes a fourth voltage-dividing resistor module, and the fourth voltage-dividing resistor module is electrically connected between the voltage source and a power supply terminal of the voltage stabilizing module.

[0024] Optionally, the motor temperature compensation circuit also includes a first filter capacitor module and a second filter capacitor module, the first filter capacitor module is electrically connected between the first end of the temperature sensor and the second end of the temperature sensor, the first end of the second filter capacitor module is electrically connected to the output end of the voltage stabilizing module, and the second end of the second filter capacitor module is grounded.

[0025] Optionally, the motor temperature compensation circuit also includes a third filter capacitor module and a filter resistor module, the first end of the third filter capacitor module is grounded, the second end of the third filter capacitor module is electrically connected to the second end of the filter resistor module and the voltage collection end of the micro control unit respectively, and the first end of the filter resistor module is electrically connected to the output end of the differential amplifier module.

[0026] Optionally, the voltage drop bearing module is a triode structure.

[0027] According to another aspect of the present application, an electronic device is provided, and the electronic device includes: any one of the motor temperature compensation circuits described above.

[0028] By applying the technical solution of the present application, two constant current source modules are turned on successively, and a microcontroller unit is used to collect the circuit temperature values ​​of the two constant current source modules. Due to the compensation provided by the two constant current source modules, the influence of the systematic errors of the operational amplifier circuit, the constant current source circuit, and the temperature sensor inside the circuit is eliminated, and the accuracy of motor temperature collection and analysis is improved, thereby solving the problem that the existing solution does not take into account the deviations of the internal circuit resistance, operational amplifier, and constant current source generating circuit, resulting in low accuracy of motor temperature detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings constituting part of the present application are used to provide a further understanding of the present application. The exemplary embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0030] Figure 1 A first schematic diagram of a motor temperature compensation circuit provided in an embodiment of the present application is shown;

[0031] Figure 2 A second schematic diagram of a motor temperature compensation circuit provided according to an embodiment of the present application is shown;

[0032] Figure 3A third schematic diagram of a motor temperature compensation circuit provided according to an embodiment of the present application is shown.

[0033] The above drawings include the following reference numerals:

[0034] 100, differential amplifier module; 200, first constant current source module; 300, second constant current source module; 400, micro control unit. DETAILED DESCRIPTION

[0035] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0036] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0037] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application 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 comprising 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.

[0038] As introduced in the background technology, at present, most of them use the traditional motor temperature sampling circuit, which connects the temperature sensor in series and parallel with the resistor to form a voltage divider circuit. When the sensor resistance changes, the resistance of the series and parallel circuit changes accordingly, and the motor temperature is calculated by the voltage divider value. Furthermore, in order to improve the accuracy of the acquisition circuit, a constant current source circuit will be added, and a constant current will flow through the temperature sensor. When the sensor resistance changes, a changing voltage value is output, so as to calculate a more accurate motor temperature. In order to solve the problem that the existing solution does not take into account the deviation of the internal resistance, operational amplifier, and constant current source generating circuit of the circuit, resulting in low accuracy of motor temperature detection, the embodiments of the present application provide a motor temperature compensation circuit and electronic equipment.

[0039] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0040] The present application provides a motor temperature compensation circuit, such as Figure 1 As shown, the motor temperature compensation circuit includes:

[0041] a temperature sensor RM, wherein a first end of the temperature sensor RM is electrically connected to a voltage source VCC, and the temperature sensor RM is located inside the motor and is used to detect the temperature of the motor.

[0042] The temperature sensor is a resistance temperature sensor. Depending on the installation position of the temperature sensor, the voltage at different positions of the motor can be detected. For example, the bearing temperature and the winding temperature of the motor can be detected.

[0043] The differential amplifier module 100 has a first input terminal, a second input terminal and an output terminal. The first input terminal of the differential amplifier module 100 is electrically connected to the first terminal of the temperature sensor RM, and the second input terminal of the differential amplifier module 100 is electrically connected to the second terminal of the temperature sensor RM.

[0044] The voltage drop bearing module Q3 has a first end, a second end and a third end, and the third end of the voltage drop bearing module Q3 is electrically connected to the second end of the temperature sensor RM;

[0045] A voltage stabilizing module U1, wherein the power supply end of the voltage stabilizing module U1 is electrically connected to the voltage source VCC and the first end of the voltage drop bearing module Q3 respectively;

[0046] The voltage stabilizing module may be a voltage stabilizing diode.

[0047] Two constant current source modules, namely a first constant current source module 200 and a second constant current source module 300, wherein the conduction end of the first constant current source module 200 is electrically connected to the output end of the voltage stabilizing module U1, the second end of the voltage drop bearing module Q3 and the conduction end of the second constant current source module 300, respectively, and the first constant current source module 200 and the second constant current source module 300 are used to compensate for the temperature of the motor detected by the temperature sensor RM;

[0048] A microcontrol unit 400, wherein the first control end of the microcontrol unit 400 is electrically connected to the control end of the first constant current source module 200, the second control end of the microcontrol unit 400 is electrically connected to the control end of the second constant current source module 300, and the voltage collection end of the microcontrol unit 400 is electrically connected to the output end of the differential amplifier module 100.

[0049] In the above-mentioned motor temperature compensation circuit, two constant current source modules are turned on successively, and a microcontroller unit is used to collect the circuit temperature values ​​of the two constant current source modules. Due to the compensation provided by the two constant current source modules, the influence of the systematic errors of the operational amplifier circuit, the constant current source circuit, and the temperature sensor inside the circuit is eliminated, thereby improving the accuracy of motor temperature collection and analysis, thereby solving the problem that the existing solution does not take into account the deviations of the internal circuit resistance, operational amplifier, and constant current source generating circuit, resulting in low accuracy of motor temperature detection.

[0050] In one embodiment of the present application, Figure 2 As shown, the differential amplifier module 100 includes a first operational amplifier resistor module R1, a second operational amplifier resistor module R2, a third operational amplifier resistor module R3, a fourth operational amplifier resistor module R4 and a first operational amplifier U2. The first end of the first operational amplifier resistor module R1 is electrically connected to the first end of the temperature sensor RM, the first end of the third operational amplifier resistor module R3 is electrically connected to the second end of the temperature sensor RM, the non-inverting input end of the first operational amplifier U2 is electrically connected to the second end of the first operational amplifier resistor module R1 and the second end of the second operational amplifier resistor module R2, respectively, the inverting input end of the first operational amplifier U2 is electrically connected to the second end of the third operational amplifier resistor module R3 and the first end of the fourth operational amplifier resistor module R4, respectively, the output end of the first operational amplifier U2 is electrically connected to the second end of the fourth operational amplifier resistor module R4 and the voltage collection end of the micro control unit 400, and the first end of the second operational amplifier resistor module R2 is grounded.

[0051] Specifically, by setting the first operational amplifier resistor module R1, the second operational amplifier resistor module R2, the third operational amplifier resistor module R3, the fourth operational amplifier resistor module R4 and the first operational amplifier U2, a stable circuit temperature value is provided for the micro control unit.

[0052] In one embodiment of the present application, Figure 2As shown, the first constant current source module 200 includes a first power switch device Q1 and a first constant current source resistor module R8, the second constant current source module 300 includes a second power switch device Q2 and a second constant current source resistor module R9, the drain of the first power switch device Q1 is electrically connected to the second end of the first constant current source resistor module R8, the drain of the second power switch device Q2 is electrically connected to the second end of the second constant current source resistor module R9, the gate of the first power switch device Q1 is electrically connected to the first control end of the micro control unit 400, the gate of the second power switch device Q2 is electrically connected to the second control end of the micro control unit 400, the first end of the first constant current source resistor module R8 and the first end of the second constant current source resistor module R9 are electrically connected to the output end of the voltage stabilizing module U1, respectively, and the input end of the voltage stabilizing module U1, the source of the first power switch device Q1 and the source of the second power switch device Q2 are grounded, respectively.

[0053] Specifically, the two power switching devices can be NMOS, and the two power switching devices are turned on successively to provide compensation to eliminate the influence of systematic errors of the operational amplifier circuit, constant current source circuit, and temperature sensor inside the circuit, thereby improving the accuracy of motor temperature collection and analysis. The two constant current source resistor modules are used for voltage limiting.

[0054] In one embodiment of the present application, Figure 2 As shown, the above-mentioned motor temperature compensation circuit also includes an isolation voltage stabilizing module U3, the in-phase input terminal of the above-mentioned isolation voltage stabilizing module U3 is electrically connected to the first end of the above-mentioned temperature sensor RM, and the inverting input terminal of the above-mentioned isolation voltage stabilizing module U3 is electrically connected to the output terminal of the above-mentioned isolation voltage stabilizing module U3 and the second input terminal of the above-mentioned differential amplifier module 100.

[0055] Specifically, the isolation and voltage stabilization module U3 may be a second operational amplifier, and is used for isolation and voltage stabilization.

[0056] In one embodiment of the present application, Figure 2 As shown, the motor temperature compensation circuit further includes a fourth voltage-dividing resistor module R10 , and the fourth voltage-dividing resistor module R10 is electrically connected between the voltage source VCC and the power supply terminal of the voltage stabilizing module U1 .

[0057] Specifically, the fourth voltage-dividing resistor module is used to divide the voltage of the voltage source.

[0058] In one embodiment of the present application, Figure 2As shown, the motor temperature compensation circuit also includes a first filter capacitor module C1 and a second filter capacitor module C3. The first filter capacitor module C1 is electrically connected between the first end of the temperature sensor RM and the second end of the temperature sensor RM. The first end of the second filter capacitor module C3 is electrically connected to the output end of the voltage stabilizing module U1, and the second end of the second filter capacitor module C3 is grounded.

[0059] Specifically, the voltage across the temperature sensor is filtered by the first filter capacitor module C1 and the second filter capacitor module C3.

[0060] In one embodiment of the present application, Figure 2 As shown, the motor temperature compensation circuit also includes a third filter capacitor module C2 and a filter resistor module R11. The first end of the third filter capacitor module C2 is grounded, and the second end of the third filter capacitor module C2 is electrically connected to the second end of the filter resistor module R11 and the voltage collection end of the micro control unit 400 respectively, and the first end of the filter resistor module R11 is electrically connected to the output end of the differential amplifier module 100.

[0061] Specifically, the voltage output from the output end of the differential amplifier module is filtered by the RC filter structure composed of the third filter capacitor module C2 and the filter resistor module R11.

[0062] In one embodiment of the present application, the voltage drop bearing module is a triode structure.

[0063] In one embodiment of the present application, the micro control unit is used to perform the following steps:

[0064] When only the first power switch device is turned on, obtaining a first collection voltage;

[0065] When only the second power switch device is turned on, obtaining a second collection voltage;

[0066] according to

[0067] Determine the resistance value of the temperature sensor;

[0068] Among them, RM represents the above-mentioned temperature sensor, R3 is the above-mentioned third operational amplifier resistor module, R4 is the above-mentioned fourth operational amplifier resistor module, R5 is the first voltage-dividing resistor module, R6 is the second voltage-dividing resistor module, R7 is the third voltage-dividing resistor module, R8 is the above-mentioned first constant current source resistor module, R9 is the above-mentioned second constant current source resistor module, Vo1 is the above-mentioned first acquisition voltage, Vo2 is the above-mentioned second acquisition voltage, VCC is the above-mentioned voltage source, VU1 is the voltage between the first end of the above-mentioned temperature sensor and the first voltage-dividing resistor module when only the above-mentioned first power switching device is turned on, the above-mentioned first voltage-dividing resistor module is electrically connected between the above-mentioned voltage source and the first end of the above-mentioned temperature sensor, the first end of the above-mentioned second voltage-dividing resistor module is electrically connected to the first end of the above-mentioned temperature sensor, the second end of the above-mentioned second voltage-dividing resistor module is electrically connected to the second end of the above-mentioned temperature sensor, and the above-mentioned third voltage-dividing resistor module is electrically connected between the second end of the above-mentioned second voltage-dividing resistor module and the third end of the above-mentioned voltage drop bearing module.

[0069] Specifically, after comprehensively considering the errors in the circuit, the output Vo calculation formula can be obtained as follows:

[0070]

[0071] like Figure 3 As shown, V1 is the voltage between the first end of RM and the first end of R6, and V2 is the voltage between the second end of RM and the second end of R6;

[0072] By using the output Vo calculation formula, we can know that the error is concentrated in

[0073] That is, it is caused by the voltage deviation of V1 and the operational amplifier resistance deviation of R1, R2, R3, and R4. To reduce the deviation of V1, the constant current source circuit needs to work, the resistance value of R5 needs to be as large as possible, and the operational amplifier resistance deviation of R1, R2, R3, and R4 needs to calculate this part of the error (the voltage deviation of V1 and the operational amplifier resistance deviation of R1, R2, R3, and R4) and eliminate it in the final calculation.

[0074] R8, R9, R10, U1, Q1, Q2, Q3, C3, and VCC form a constant current source circuit. When the first constant current source module is working, Q1 is turned on, Q2 is turned off, and U1 outputs a constant voltage VU1. At this time, the output current IR8 of the constant current source circuit is:

[0075] Similarly, when the second constant current source module is working, Q2 is turned on and Q1 is turned off. At this time, the output current IR9 of the constant current source circuit is:

[0076] Denoted as:

[0077] Then IR8 = NIR9;

[0078] When the microcontroller controls Q1 to turn on, that is, the first constant current source module is turned on, the output Vo1 is:

[0079]

[0080] at this time,

[0081] When the microcontroller controls Q2 to turn on, that is, the second constant current source is turned on, the output Vo2 is:

[0082]

[0083] at this time,

[0084] V11 and V21 are the voltages across RM when the first constant current source module is working, and V12 and V22 are the voltages across RM when the second constant current source module is working;

[0085] And because IR8=NIR9, V11-V21=N(V12-V22).

[0086] We can get:

[0087] in,

[0088]

[0089]

[0090] so

[0091] So we can calculate The error value is:

[0092] Taking the first constant current source as the main calculation circuit, we can get:

[0093]

[0094] Therefore, the resistance RM of the motor temperature sensor can be calculated as:

[0095]

[0096] The present application also provides an electronic device, the electronic device comprising: any one of the above-mentioned motor temperature compensation circuits. By successively conducting two constant current source modules, a microcontroller unit is used to collect the circuit temperature values ​​of the two constant current source modules. Due to the compensation provided by the two constant current source modules, the influence of the systematic errors of the operational amplifier circuit, the constant current source circuit, and the temperature sensor inside the circuit is eliminated, and the accuracy of motor temperature acquisition and analysis is improved, thereby solving the problem that the existing solution does not consider the deviation of the internal circuit resistance, operational amplifier, and constant current source generation circuit, resulting in low accuracy of motor temperature detection.

[0097] It should be noted that the above electrical connection can be a direct electrical connection or an indirect electrical connection. Direct electrical connection means that two devices are directly connected, and indirect electrical connection means that other devices such as capacitors and resistors are also connected between the connected A and B.

[0098] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0099] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0100] 1) The motor temperature compensation circuit of the present application successively turns on two constant current source modules and uses a microcontroller unit to collect the circuit temperature values ​​of the two constant current source modules. Due to the compensation provided by the two constant current source modules, the influence of the systematic errors of the operational amplifier circuit, the constant current source circuit, and the temperature sensor inside the circuit is eliminated, thereby improving the accuracy of motor temperature collection and analysis, thereby solving the problem that the existing solution does not take into account the deviations of the internal circuit resistance, operational amplifier, and constant current source generating circuit, resulting in low accuracy of motor temperature detection.

[0101] 2) The electronic device of the present application successively turns on two constant current source modules and uses a microcontroller unit to collect the circuit temperature values ​​of the two constant current source modules. Due to the compensation provided by the two constant current source modules, the influence of the systematic errors of the operational amplifier circuit, the constant current source circuit, and the temperature sensor inside the circuit is eliminated, thereby improving the accuracy of motor temperature collection and analysis, thereby solving the problem that the existing solution does not take into account the deviations of the internal circuit resistance, operational amplifier, and constant current source generating circuit, resulting in low accuracy of motor temperature detection.

[0102] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A motor temperature compensation circuit, characterized in that: include: a temperature sensor, wherein a first end of the temperature sensor is electrically connected to a voltage source, the temperature sensor is located inside the motor and is used to detect the temperature of the motor, A differential amplifier module, comprising a first input terminal, a second input terminal and an output terminal, wherein the first input terminal of the differential amplifier module is electrically connected to the first terminal of the temperature sensor, and the second input terminal of the differential amplifier module is electrically connected to the second terminal of the temperature sensor; A voltage drop bearing module having a first end, a second end and a third end, wherein the third end of the voltage drop bearing module is electrically connected to the second end of the temperature sensor; A voltage stabilizing module, wherein a power supply end of the voltage stabilizing module is electrically connected to the voltage source and the first end of the voltage drop bearing module respectively; Two constant current source modules, namely a first constant current source module and a second constant current source module, the conduction end of the first constant current source module is electrically connected to the output end of the voltage stabilizing module, the second end of the voltage drop bearing module and the conduction end of the second constant current source module respectively, and the first constant current source module and the second constant current source module are used to compensate for the temperature of the motor detected by the temperature sensor; A microcontroller unit, wherein a first control end of the microcontroller unit is electrically connected to a control end of the first constant current source module, a second control end of the microcontroller unit is electrically connected to a control end of the second constant current source module, and a voltage collection end of the microcontroller unit is electrically connected to an output end of the differential amplifier module.

2. The motor temperature compensation circuit according to claim 1, characterized in that: The differential amplifier module includes a first operational amplifier resistor module, a second operational amplifier resistor module, a third operational amplifier resistor module, a fourth operational amplifier resistor module and a first operational amplifier, wherein a first end of the first operational amplifier resistor module is electrically connected to a first end of the temperature sensor, a first end of the third operational amplifier resistor module is electrically connected to a second end of the temperature sensor, a non-inverting input end of the first operational amplifier is electrically connected to a second end of the first operational amplifier resistor module and a second end of the second operational amplifier resistor module, respectively, an inverting input end of the first operational amplifier is electrically connected to a second end of the third operational amplifier resistor module and a first end of the fourth operational amplifier resistor module, an output end of the first operational amplifier is electrically connected to a second end of the fourth operational amplifier resistor module and a voltage collection end of the micro control unit, respectively, and a first end of the second operational amplifier resistor module is grounded.

3. The motor temperature compensation circuit according to claim 2, characterized in that: The first constant current source module includes a first power switch device and a first constant current source resistor module, the second constant current source module includes a second power switch device and a second constant current source resistor module, the drain of the first power switch device is electrically connected to the second end of the first constant current source resistor module, the drain of the second power switch device is electrically connected to the second end of the second constant current source resistor module, the gate of the first power switch device is electrically connected to the first control end of the micro control unit, the gate of the second power switch device is electrically connected to the second control end of the micro control unit, the first end of the first constant current source resistor module and the first end of the second constant current source resistor module are electrically connected to the output end of the voltage stabilizing module respectively, and the input end of the voltage stabilizing module, the source of the first power switch device and the source of the second power switch device are grounded respectively.

4. The motor temperature compensation circuit according to claim 3, characterized in that: The microcontroller unit is used to perform the following steps: Acquiring a first collection voltage when only the first power switch device is turned on; When only the second power switch device is turned on, obtaining a second collection voltage; according to Determining the resistance value of the temperature sensor; Among them, RM represents the temperature sensor, R3 is the third op amp resistor module, R4 is the fourth op amp resistor module, R5 is the first voltage divider resistor module, R6 is the second voltage divider resistor module, R7 is the third voltage divider resistor module, R8 is the first constant current source resistor module, R9 is the second constant current source resistor module, Vo1 is the first acquisition voltage, Vo2 is the second acquisition voltage, VCC is the voltage source, VU1 is the voltage between the first end of the temperature sensor and the first voltage divider resistor module when only the first power switch device is turned on, the first voltage divider resistor module is electrically connected between the voltage source and the first end of the temperature sensor, the first end of the second voltage divider resistor module is electrically connected to the first end of the temperature sensor, the second end of the second voltage divider resistor module is electrically connected to the second end of the temperature sensor, and the third voltage divider resistor module is electrically connected between the second end of the second voltage divider resistor module and the third end of the voltage drop bearing module.

5. The motor temperature compensation circuit according to claim 1, characterized in that: The motor temperature compensation circuit also includes an isolation voltage stabilization module, the in-phase input end of the isolation voltage stabilization module is electrically connected to the first end of the temperature sensor, and the inverting input end of the isolation voltage stabilization module is electrically connected to the output end of the isolation voltage stabilization module and the second input end of the differential amplifier module.

6. The motor temperature compensation circuit according to claim 1, characterized in that: The motor temperature compensation circuit further includes a fourth voltage-dividing resistor module, and the fourth voltage-dividing resistor module is electrically connected between the voltage source and the power supply terminal of the voltage stabilizing module.

7. The motor temperature compensation circuit according to claim 1, characterized in that: The motor temperature compensation circuit also includes a first filter capacitor module and a second filter capacitor module, the first filter capacitor module is electrically connected between the first end of the temperature sensor and the second end of the temperature sensor, the first end of the second filter capacitor module is electrically connected to the output end of the voltage stabilizing module, and the second end of the second filter capacitor module is grounded.

8. The motor temperature compensation circuit according to claim 1, characterized in that: The motor temperature compensation circuit also includes a third filter capacitor module and a filter resistor module, the first end of the third filter capacitor module is grounded, the second end of the third filter capacitor module is electrically connected to the second end of the filter resistor module and the voltage collection end of the micro control unit respectively, and the first end of the filter resistor module is electrically connected to the output end of the differential amplifier module.

9. The motor temperature compensation circuit according to any one of claims 1 to 8, characterized in that: The voltage drop bearing module is a triode structure.

10. An electronic device, characterized in that: include: A motor temperature compensation circuit as claimed in any one of claims 1 to 9.

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