Motor, temperature regulation and control system and method thereof, medium, controller and program product

Abstract

The invention provides a motor and a temperature regulation and control system and method thereof, a medium, a controller and a program product, and the motor temperature regulation and control system comprises a temperature detection circuit which is used for detecting the internal temperature of the motor; the thermoelectric conversion circuit is used for converting heat energy into electric energy so as to reduce the internal temperature of the motor; the heating circuit is used for heating to increase the internal temperature of the motor; and the control unit is used for controlling the thermoelectric conversion circuit and / or the heating circuit according to the internal temperature of the motor detected by the temperature detection circuit so as to adjust the internal temperature of the motor. According to the scheme, the internal temperature of the motor can be dynamically adjusted, it is guaranteed that the internal temperature of the motor is within a proper temperature interval, and the reliability of the motor is improved.

Description

Technical Field

[0001] The present invention relates to the field of control, and in particular to a motor and a temperature control system, method, medium, controller and program product thereof. Background Art

[0002] The main function of the motor is to provide driving force. To ensure continuous driving force, the reliability of the motor is crucial. The motor faces challenges in different harsh working conditions. Common harsh working conditions are low-temperature starting and high-temperature operation. Under low-temperature conditions, the motor is at risk of freezing the shaft and the load is heavier. The motor is relatively difficult to start and the reliability of the motor start is reduced. Under high-temperature conditions, long-term operation of the motor is likely to cause the internal temperature to be too high, which will seriously affect the motor performance and safety. Summary of the invention

[0003] The main purpose of the present invention is to overcome the defects of the above-mentioned related technologies and provide a motor and its temperature control system, method, medium, controller and program product to solve the problem of the motor running under harsh working conditions in the related technologies.

[0004] On the one hand, the present invention provides a motor temperature control system, comprising: a temperature detection circuit for detecting the internal temperature of the motor; a thermoelectric conversion circuit for converting thermal energy into electrical energy to reduce the internal temperature of the motor; a heating circuit for generating heat to increase the internal temperature of the motor; and a control unit for obtaining the internal temperature of the motor detected by the temperature detection circuit, and controlling the thermoelectric conversion circuit and / or the heating circuit according to the internal temperature of the motor to adjust the internal temperature of the motor.

[0005] Optionally, the control unit controls the thermoelectric conversion circuit and / or the heating circuit to adjust the internal temperature of the motor according to the internal temperature of the motor detected by the temperature detection circuit, including: in the motor standby mode, when it is identified that the motor is in a high temperature condition, controlling the thermoelectric conversion circuit to convert the internal heat energy of the motor into electrical energy to reduce the internal temperature of the motor; when it is identified that the motor is in a low temperature condition, controlling the heating circuit to generate heat to increase the internal temperature of the motor; wherein, when the internal temperature of the motor detected by the temperature detection circuit is less than a preset low temperature threshold, it is identified that the motor is in a low temperature condition; when the internal temperature of the motor detected by the temperature detection circuit is greater than a preset high temperature threshold, it is identified that the motor is in a low temperature condition; in the motor working mode, controlling the thermoelectric conversion circuit to convert the internal heat energy of the motor into electrical energy to reduce the internal temperature of the motor.

[0006] Optionally, it also includes: an electric energy storage circuit for storing electric energy; the control unit is also used to: control the thermoelectric conversion circuit to convert the internal thermal energy of the motor into electric energy, and then transmit the converted electric energy to the electric energy storage circuit for storage; in the motor standby mode, when it is recognized that the motor is in a low temperature condition, power is supplied to the heating circuit through the electric energy storage circuit, thereby controlling the heating circuit to generate heat.

[0007] Optionally, it also includes: a standby charging circuit, used to provide electric energy to the electric energy storage circuit for charging in the motor standby mode; the control unit is also used to: control the standby charging circuit to provide electric energy to the electric energy storage circuit for charging in the motor standby mode.

[0008] Optionally, the control unit is also used to adjust the operating limits of the motor according to the size of the internal temperature of the motor detected by the temperature detection circuit, and the operating limits include at least one of: motor current limit, motor starting current, motor starting mode, motor speed limit and motor power limit.

[0009] Optionally, the control unit adjusts the operating restrictions of the motor according to the detected internal temperature of the motor, including: when it is identified that the motor is in a low temperature state, when the detected internal temperature of the motor is less than a second preset temperature threshold, increasing the current limit value of the motor by a first preset current value; wherein, when the detected internal temperature of the motor is less than a sixth preset temperature threshold, it is identified that the motor is in a low temperature state; when it is identified that the motor is in a high temperature state, when the detected internal temperature of the motor is greater than a third preset temperature threshold, limiting the current of the motor according to a preset current limit value; wherein, when the detected internal temperature of the motor is greater than the first preset temperature threshold, it is identified that the motor is in a high temperature state.

[0010] Optionally, the control unit is also used to: when the detected internal temperature of the motor is lower than a fourth preset temperature threshold, increase the current limiting value of the motor by a first preset current value, and increase the starting current of the motor by a second preset current value; and / or, when the detected internal temperature of the motor is lower than a fifth preset temperature threshold, increase the current limiting value of the motor by a first preset current value, and increase the starting current of the motor by a second preset current value, and switch the starting mode of the motor.

[0011] Optionally, the control unit is also used to: when the current of the motor is limited according to a preset current limiting value for a first preset time, if the internal temperature of the motor detected again is greater than a third preset temperature threshold, the speed of the motor is limited; otherwise, the current limitation of the motor is released.

[0012] Optionally, the control unit is also used to: when the time for executing the speed limit of the motor reaches a second preset time, if the internal temperature of the motor detected again is greater than a third preset temperature threshold, execute the power limitation of the motor; otherwise, release the current limitation and speed limitation of the motor.

[0013] On the other hand, the present invention provides a motor temperature control method, the motor comprising: a temperature detection circuit for detecting the internal temperature of the motor; a thermoelectric conversion circuit for converting thermal energy into electrical energy to reduce the internal temperature of the motor; a heating circuit for generating heat to increase the internal temperature of the motor; the motor temperature control method comprises: obtaining the internal temperature of the motor detected by the temperature detection circuit; controlling the thermoelectric conversion circuit and / or the heating circuit according to the internal temperature of the motor to adjust the internal temperature of the motor.

[0014] Optionally, according to the internal temperature of the motor detected by the temperature detection circuit, the thermoelectric conversion circuit and / or the heating circuit are controlled to adjust the internal temperature of the motor, including: in the motor standby mode, when it is identified that the motor is in a high temperature condition, the thermoelectric conversion circuit is controlled to convert the internal heat energy of the motor into electrical energy to reduce the internal temperature of the motor; when it is identified that the motor is in a low temperature condition, the heating circuit is controlled to generate heat to increase the internal temperature of the motor; wherein, when the internal temperature of the motor detected by the temperature detection circuit is less than a preset low temperature threshold, it is identified that the motor is in a low temperature condition; when the internal temperature of the motor detected by the temperature detection circuit is greater than a preset high temperature threshold, it is identified that the motor is in a low temperature condition; in the motor working mode, the thermoelectric conversion circuit is controlled to convert the internal heat energy of the motor into electrical energy to reduce the internal temperature of the motor.

[0015] Optionally, the motor further includes: an electric energy storage circuit for storing electric energy; the control method further includes: controlling the thermoelectric conversion circuit to convert the internal thermal energy of the motor into electric energy, and then transmitting the converted electric energy to the electric energy storage circuit for storage; in the motor standby mode, when it is recognized that the motor is in a low temperature condition, power is supplied to the heating circuit through the electric energy storage circuit, thereby controlling the heating circuit to generate heat.

[0016] Optionally, the motor further includes: a standby charging circuit for providing electric energy to the electric energy storage circuit for charging in the motor standby mode; the control method further includes: controlling the standby charging circuit to provide electric energy to the electric energy storage circuit for charging in the motor standby mode.

[0017] Optionally, it also includes: adjusting the operation limit of the motor according to the internal temperature of the motor detected by the temperature detection circuit, and the operation limit includes: at least one of motor current limit, motor starting current, motor starting mode, motor speed limit and motor power limit.

[0018] Optionally, the operating restrictions of the motor are adjusted according to the internal temperature of the motor detected by the temperature detection circuit, including: when it is identified that the motor is in a low temperature state, when the detected internal temperature of the motor is less than a second preset temperature threshold, the current limit value of the motor is increased by a first preset current value; wherein, when the detected internal temperature of the motor is less than a sixth preset temperature threshold, it is identified that the motor is in a low temperature state; when it is identified that the motor is in a high temperature state, when the detected internal temperature of the motor is greater than a third preset temperature threshold, the current of the motor is limited according to a preset current limit value; wherein, when the detected internal temperature of the motor is greater than the first preset temperature threshold, it is identified that the motor is in a high temperature state.

[0019] Optionally, it also includes: when the detected internal temperature of the motor is less than a fourth preset temperature threshold, the current limiting value of the motor is increased by a first preset current value, and the starting current of the motor is increased by a second preset current value; and / or, when the detected internal temperature of the motor is less than a fifth preset temperature threshold, the current limiting value of the motor is increased by a first preset current value, and the starting current of the motor is increased by a second preset current value, and the starting mode of the motor is switched.

[0020] Optionally, it also includes: when the current of the motor is limited according to the preset current limiting value for a first preset time, if the internal temperature of the motor detected again is greater than a third preset temperature threshold, the speed limit of the motor is executed; otherwise, the current limit of the motor is released.

[0021] Optionally, it also includes: when the time for executing the speed limit of the motor reaches a second preset time, if the internal temperature of the motor detected again is greater than a third preset temperature threshold, the power limitation of the motor is executed, otherwise, the current limitation and speed limitation of the motor are released.

[0022] Another aspect of the present invention provides a storage medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the steps of any of the aforementioned motor temperature control methods.

[0023] In another aspect, the present invention provides a controller for a motor, comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of any of the aforementioned motor temperature control methods are implemented.

[0024] In another aspect, the present invention provides a motor, comprising any of the motor temperature control systems described above.

[0025] In another aspect, the present invention provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the steps of any of the above-mentioned motor temperature control methods are implemented.

[0026] According to the technical solution of the present invention, the thermoelectric conversion circuit or the heating circuit is controlled according to the working condition of the motor, and the internal temperature of the motor is dynamically adjusted to ensure that the internal temperature of the motor is within a suitable temperature range, thereby improving the reliability of the motor.

[0027] According to the technical solution of the present invention, the motor operating conditions are distinguished according to the collected temperature data, and the protection limits of the motor are dynamically adjusted according to the different operating conditions. High temperature increases the motor limits to limit the motor performance and protect the motor safety; low temperature removes the motor limits to improve the reliability of motor starting and operation.

[0028] According to the technical solution of the present invention, triple high temperature limits and triple low temperature limits are set, and different limits are added as the temperature increases, and different limits are removed as the temperature decreases. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0030] Figure 1 A schematic diagram of the structure of a motor temperature control system according to an embodiment of the present invention is shown;

[0031] Figure 2 A control flow chart showing controlling the thermoelectric conversion circuit and / or the heating circuit to adjust the internal temperature of the motor is shown;

[0032] Figure 3 is a control flow chart for adjusting the operating limit of the motor according to the present invention;

[0033] Figure 4 is a method schematic diagram of an embodiment of a motor temperature control method provided by the present invention;

[0034] Figure 5 It is a method schematic diagram of another embodiment of the motor temperature control method provided by the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention 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 present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof 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 that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0037] Under low temperature conditions, the motor is at risk of freezing the shaft and the load is heavier. It is relatively difficult to start the motor, and the reliability of the motor start-up is reduced. At this time, the motor restrictions need to be temporarily lifted to improve the reliability of the motor start-up. Under high temperature conditions, long-term operation of the motor is prone to excessive internal temperature, which will seriously affect the motor performance and motor safety. At this time, additional motor restrictions need to be added to reduce the internal temperature of the motor to ensure motor safety. For different working conditions, the motor control strategy needs to be dynamically adjusted.

[0038] The invention provides a motor temperature control system.

[0039] Figure 1 FIG. 2 shows a schematic diagram of the structure of a motor temperature control system according to an embodiment of the present invention. Figure 1 As shown, the motor temperature control system includes: a temperature detection circuit S0, a thermoelectric conversion circuit S1, a heating circuit S4 and a control unit.

[0040] The temperature detection circuit S0 is used to detect the internal temperature of the motor. Specifically, the temperature detection unit S0 detects the internal temperature T of the motor and outputs a temperature signal T to the control unit.

[0041] Thermoelectric conversion circuit S1 is used to convert thermal energy into electrical energy to reduce the internal temperature of the motor. Specifically, when the motor is in a high temperature condition, the thermoelectric conversion circuit S1 converts thermal energy into electrical energy to reduce the internal temperature of the motor.

[0042] The heating circuit S4 is used to generate heat to increase the internal temperature of the motor. Specifically, when the motor is in a low temperature condition, the heating circuit S4 generates heat to increase the internal temperature of the motor.

[0043] The control unit is used to obtain the internal temperature of the motor detected by the temperature detection circuit, and control the thermoelectric conversion circuit and / or the heating circuit according to the internal temperature of the motor to adjust the internal temperature of the motor.

[0044] The control unit may specifically be an MCU, for example, an MCU (micro control unit) in a motor controller, which controls the thermoelectric conversion circuit S1 and / or the heating circuit S4 according to the internal temperature T of the motor detected by the temperature detection circuit S0 to adjust the internal temperature of the motor. Figure 2 The control flow chart of controlling the thermoelectric conversion circuit and / or the heating circuit to adjust the internal temperature of the motor is shown. Figure 2 As shown, after the controller MCU parameters are initialized, the MCU identifies the temperature signal of the temperature detection circuit S0, and outputs a corresponding PWM signal according to the temperature signal T of the internal temperature of the motor output by the temperature detection circuit S0, so as to control the thermoelectric conversion circuit S0 and / or the heating circuit S4 to adjust the internal temperature of the motor.

[0045] In a specific embodiment, the control unit controls the thermoelectric conversion circuit and / or the heating circuit according to the internal temperature of the motor detected by the temperature detection circuit, which may specifically include: in the motor standby mode, when it is identified that the motor is in a high temperature condition, controlling the thermoelectric conversion circuit to convert the internal heat energy of the motor into electrical energy to reduce the internal temperature of the motor; when it is identified that the motor is in a low temperature condition, controlling the heating circuit to generate heat to increase the internal temperature of the motor; wherein, when the internal temperature of the motor detected by the temperature detection circuit is less than a preset low temperature threshold, it is identified that the motor is in a low temperature condition; when the internal temperature of the motor detected by the temperature detection circuit is greater than a preset high temperature threshold, it is identified that the motor is in a low temperature condition.

[0046] Specifically, in standby mode, the motor temperature control system controls the internal temperature of the motor within an appropriate temperature range. The control unit MUC selectively outputs PWM signals 1 and 2 according to the temperature signal T. The MCU recognizes that the motor is in a high-temperature condition, and outputs PWM signal 2 to the thermoelectric conversion circuit S1, which controls the thermoelectric conversion circuit to convert the internal heat energy of the motor into electrical energy to reduce the internal temperature of the motor. The MCU recognizes that the motor is in a low-temperature condition, and outputs PWM signal 1 to the heating circuit S4, which controls the heating circuit S4 to generate heat to raise the motor temperature (see Figure 1 shown).

[0047] In a specific embodiment, the control unit controls the thermoelectric conversion circuit and / or the heating circuit according to the internal temperature of the motor detected by the temperature detection circuit, which may specifically include: in the motor working mode, controlling the thermoelectric conversion circuit S1 to convert the internal thermal energy of the motor into electrical energy to reduce the internal temperature of the motor.

[0048] Specifically, in the motor working mode, the main working circuit is the thermoelectric conversion circuit S1. The control unit MCU outputs a PWM signal 2 to the thermoelectric conversion circuit S1 to reduce the motor temperature.

[0049] Furthermore, the motor temperature control system further includes an electric energy storage circuit S2 for storing electric energy (refer to Figure 1 As shown). The electric energy storage circuit S2 is connected to the thermoelectric conversion circuit S1. The control unit is also used to: control the thermoelectric conversion circuit to convert the internal thermal energy of the motor into electrical energy, and then transfer the converted electrical energy to the electric energy storage circuit for storage. That is, in the motor standby mode (under low temperature conditions) or the motor working mode, control the thermoelectric conversion circuit S1 to convert the internal thermal energy of the motor into electrical energy, and then transfer the converted electrical energy to the electric energy storage circuit S2 for storage. For example, in the motor working mode, the MCU outputs a PWM signal 2 to the thermoelectric conversion circuit S1 to reduce the temperature of the motor, and at the same time collects energy to the electric energy storage circuit S2 to recover energy.

[0050] Optionally, the electric energy storage circuit is also used to: when the stored power exceeds the preset power storage threshold, feedback to the control unit prompt information that the stored power has exceeded the preset power storage threshold; when the control unit receives the feedback prompt information from the electric energy storage circuit that the stored power has exceeded the preset power storage threshold, control the hot spot conversion circuit to stop converting the internal heat energy of the motor into electric energy. For example, the electric energy storage circuit feeds back the stored power Q to the MCU, and when the stored power Q exceeds the power storage threshold Q1, the MCU stops outputting the PWM signal 2.

[0051] Preferably, the control unit is further used for: in the motor standby mode, when it is identified that the motor is in a low temperature condition, supplying power to the heating circuit S4 through the electric energy storage circuit S2, thereby controlling the heating circuit to generate heat. That is, the power supply of the heating circuit S4 comes from the electric energy storage circuit S2, reducing the additional power supply and improving the energy utilization rate. The electric energy storage circuit S2 is connected to the heating circuit S4 to supply power to the heating circuit. The heating circuit S4 starts to work when it receives the PWM signal 1.

[0052] Optionally, the motor temperature control system further includes: a standby charging circuit S3, which is connected to the electric energy storage circuit S2 and is used to charge the electric energy storage circuit S2 in the motor standby mode; the control unit is also used to: control the standby charging circuit to provide electric energy to the electric energy storage circuit for charging in the motor standby mode. For example, the MCU outputs a PWM signal 3 to the standby charging circuit S3 in the standby state, and the standby charging circuit runs at low power to trickle charge the electric energy storage circuit S2 (refer to Figure 1 ).

[0053] Optionally, the control unit is further used to adjust the operation limit of the motor according to the internal temperature of the motor detected by the temperature detection circuit.

[0054] The operation restriction includes at least one of: motor current restriction, motor starting current, motor starting mode, motor speed restriction and motor power restriction. Specifically, when the motor is in a low temperature state and a high temperature state, the operation restriction of the motor is adjusted according to the detected internal temperature of the motor, wherein the operation restriction of the motor is adjusted in the low temperature state and the high temperature state, respectively, in the following manners:

[0055] A. When the motor is in low temperature state:

[0056] (1) When it is identified that the motor is in a low temperature state, when the detected internal temperature of the motor is less than a second preset temperature threshold, the current limiting value of the motor is increased by a first preset current value; wherein, when the detected internal temperature of the motor is less than a sixth preset temperature threshold (i.e., the preset low temperature threshold), it is identified that the motor is in a low temperature state.

[0057] Specifically, the MCU detects the temperature signal T and the sixth preset temperature threshold T0 and the first preset temperature threshold T1. When the temperature T is less than the threshold T0, the MCU identifies that the motor is in a low temperature state. When the temperature T is greater than the threshold T1, the MCU identifies that the motor is in a high temperature state. When the motor is in a low temperature state, the temperature T is compared with the second preset temperature threshold T2, the fourth preset temperature threshold T4 and the fifth preset temperature threshold T5. The size relationship of the three temperature thresholds is: T2>T4>T5, and each temperature threshold corresponds to a restriction release. When the temperature T is less than the threshold T2, the motor current limit is released, the motor current limit is increased, and the motor can run at a larger current.

[0058] (2) when the detected internal temperature of the motor is less than a fourth preset temperature threshold, increasing the current limit value of the motor by the first preset current value and increasing the starting current of the motor by the second preset current value;

[0059] Specifically, when the temperature T is less than the threshold value T4, the temperature is relatively low. To ensure the reliability of low-temperature starting, the motor current limit is increased while also increasing the motor starting current. A larger starting current can provide a larger starting torque. For example, more than two starting currents are set. When the motor starting current needs to be increased, the motor is started with a starting current that is larger than the current starting current.

[0060] (3) When the detected internal temperature of the motor is lower than a fifth preset temperature threshold, the current limit value of the motor is increased by a first preset current value, the starting current of the motor is increased by a second preset current value, and the starting mode of the motor is switched.

[0061] Specifically, when the temperature T is less than the threshold value T5, the motor starting mode (square wave drive) is switched on the basis of increasing the motor current limit value and the motor starting current, and the motor is driven to start at low temperature with a larger starting torque. Among them, different internal temperatures of the motor correspond to different initial values ​​of the starting torque, and the initial value of the starting torque corresponding to the internal temperature of the motor when it is less than the fifth preset temperature threshold is greater than the initial value of the starting torque corresponding to the internal temperature of the motor when it is greater than or equal to the fifth preset temperature threshold, that is, when the internal temperature of the motor is less than the fifth preset temperature threshold, the motor is driven to start at low temperature with a larger starting torque.

[0062] B. When the motor is at high temperature:

[0063] (1) When it is identified that the motor is in a high temperature state, when the detected internal temperature of the motor is greater than a third preset temperature threshold, the current of the motor is limited according to a preset current limiting value; wherein, when the detected internal temperature of the motor is greater than a first preset temperature threshold (i.e., the preset high temperature threshold), it is identified that the motor is in a high temperature state.

[0064] Specifically, the MCU detects the temperature signal T and the sixth preset temperature threshold T0 and the first preset temperature threshold T1. When the temperature T is less than the threshold T0, the MCU identifies that the motor is in a low temperature state. When the temperature T is greater than the threshold T1, the MCU identifies that the motor is in a high temperature state.

[0065] When the motor is in a high temperature state, the temperature T is compared with a third preset temperature threshold T3. When the temperature T>threshold T3, the motor current is limited according to a preset current limiting value.

[0066] (2) When the current of the motor is limited according to the preset current limiting value for a first preset time t1, if the internal temperature of the motor detected again is greater than a third preset temperature threshold, the speed limitation of the motor is executed; otherwise, the current limitation of the motor is released.

[0067] Specifically, when the temperature T>threshold T3, the motor current is limited according to the preset current limiting value, and timing t is started at the same time. When the time t accumulates to the preset value t1, the relationship between the temperature T and the threshold T3 is judged again. When the temperature T≤threshold T3, it means that the motor temperature has dropped, and the motor current limit is canceled at this time. When the temperature T>threshold T3, it means that the motor temperature has not yet dropped to the set value. At this time, on the basis of limiting the motor current, the motor speed is additionally limited, that is, the speed limit of the motor is executed. For example, when the motor speed exceeds the preset speed value, the motor current is reduced. That is, when the speed value exceeds the preset speed value, the current setting value is reduced, thereby reducing the motor current and reducing the motor speed.

[0068] (3) When the time for executing the speed limit of the motor reaches the second preset time t2, if the internal temperature of the motor detected again is greater than the third preset temperature threshold T3, the power limit of the motor is executed; otherwise, the current limit and the speed limit of the motor are released.

[0069] Specifically, the timing starts while the speed limit of the motor is executed. When the time t accumulates to the preset value t2, the relationship between the temperature T and the threshold value T3 is judged again. When the temperature T≤threshold value T3, it means that the motor temperature has dropped. At this time, the motor current limit and the speed limit are cancelled. When the temperature T>threshold value T3, it means that the motor temperature has not dropped to the set value. At this time, on the basis of limiting the motor current and limiting the motor speed, the motor power is additionally limited. For example, the motor current and voltage are detected in real time, and the real-time power of the motor is calculated. When the motor power protection is triggered, the motor voltage and current are limited. That is, the set values ​​of the motor voltage and current are set to fixed values, the motor voltage and current are limited, and the power is maintained unchanged.

[0070] Figure 3 is a control flow chart for adjusting the operating limit of the motor according to the present invention. Figure 2 As shown, six temperature thresholds are pre-set, namely temperature thresholds T0-T5. The MCU detects the temperature signal T and thresholds T0 and T1. When the temperature T is less than the threshold T0, the MCU identifies that the motor is in a low temperature state. When the temperature T is greater than the threshold T1, the MCU identifies that the motor is in a high temperature state.

[0071] When the motor is in a low temperature state, when the temperature T is less than the threshold value T2, the motor current limit is released, the motor current limit is increased, and the motor can run with a larger current. When the temperature T is less than the threshold value T4, the temperature is relatively low at this time. In order to ensure the reliability of low-temperature starting, the motor current limit is increased while the motor starting current is increased. A larger starting current can provide a larger starting torque. When the temperature T is less than the threshold value T5, the motor starting mode (square wave drive) is switched on the basis of increasing the motor current limit and the starting current, and the motor is driven to start at low temperature with a larger starting torque.

[0072] When the motor is in a high temperature state, the temperature T is judged by the temperature threshold T3. When the temperature T>threshold T3, the motor current is limited and the timing starts at the same time. When the time t accumulates to the preset value t1, the relationship between the temperature T and the threshold T3 is judged again. When the temperature T≤threshold T3, it means that the motor temperature has dropped and the motor current limit is cancelled. When the temperature T>threshold T3, it means that the motor temperature has not dropped to the set value. At this time, on the basis of limiting the motor current, the motor speed is additionally limited, and the timing starts at the same time. When the time t accumulates to the preset value t1, the relationship between the temperature T and the threshold T3 is judged again. When the temperature T≤threshold T3, it means that the motor temperature has dropped. At this time, the motor current and speed limit functions are cancelled. When the temperature T>threshold T3, it means that the motor temperature has not dropped to the set value. At this time, on the basis of limiting the motor current and speed, the motor power is limited again. When the temperature T≤threshold T1, the triple limit of the motor is released.

[0073] The present invention also provides a motor temperature control method. The motor comprises: a temperature detection circuit S0, a thermoelectric conversion circuit S1 and a heating circuit S4. The motor temperature control method can be implemented in a controller of the motor, more specifically, the method can be implemented in a microcontroller unit MCU of the controller. Figure 1 A schematic structural diagram of a motor temperature control system according to an embodiment of the present invention is shown.

[0074] The temperature detection circuit S0 is used to detect the internal temperature of the motor. Specifically, the temperature detection unit S0 detects the internal temperature T of the motor and outputs a temperature signal T to the control unit.

[0075] Thermoelectric conversion circuit S1 is used to convert thermal energy into electrical energy to reduce the internal temperature of the motor. Specifically, when the motor is in a high temperature condition, the thermoelectric conversion circuit S1 converts thermal energy into electrical energy to reduce the internal temperature of the motor.

[0076] The heating circuit S4 is used to generate heat to increase the internal temperature of the motor. Specifically, when the motor is in a low temperature condition, the heating circuit S4 generates heat to increase the internal temperature of the motor.

[0077] Figure 4 It is a method schematic diagram of an embodiment of the motor temperature control method provided by the present invention.

[0078] like Figure 4 As shown, according to an embodiment of the present invention, the motor temperature control method at least includes step S110 and step S120.

[0079] Step S110, obtaining the internal temperature of the motor detected by the temperature detection circuit.

[0080] Specifically, the internal temperature signal of the motor detected by the temperature detection circuit S0 is obtained.

[0081] Step S120, controlling the thermoelectric conversion circuit and / or the heating circuit according to the internal temperature of the motor to adjust the internal temperature of the motor.

[0082] In a specific embodiment, in the motor standby mode, when it is identified that the motor is in a high temperature condition, the thermoelectric conversion circuit is controlled to convert the internal heat energy of the motor into electrical energy to reduce the internal temperature of the motor; when it is identified that the motor is in a low temperature condition, the heating circuit is controlled to generate heat to increase the internal temperature of the motor; wherein, when the internal temperature of the motor detected by the temperature detection circuit is less than a preset low temperature threshold, it is identified that the motor is in a low temperature condition; when the internal temperature of the motor detected by the temperature detection circuit is greater than a preset high temperature threshold, it is identified that the motor is in a low temperature condition. In the motor working mode, the thermoelectric conversion circuit S1 is controlled to convert the internal heat energy of the motor into electrical energy to reduce the internal temperature of the motor.

[0083] Specifically, in standby mode, the control unit MUC selectively outputs PWM signals 1 and 2 according to the temperature signal T. The MCU recognizes that the motor is in a high-temperature condition, and outputs a PWM signal 2 to the thermoelectric conversion circuit S1, and controls the thermoelectric conversion circuit to convert the internal heat energy of the motor into electrical energy to reduce the internal temperature of the motor. The MCU recognizes that the motor is in a low-temperature condition, and outputs a PWM signal 1 to the heating circuit S4, and controls the heating circuit S4 to generate heat to raise the temperature of the motor. In the motor working mode, the main working circuit is the thermoelectric conversion circuit S1. The control unit MCU outputs a PWM signal 2 to the thermoelectric conversion circuit S1 to reduce the temperature of the motor.

[0084] Furthermore, the motor further comprises an electric energy storage circuit S2 for storing electric energy. Figure 1 As shown, the electric energy storage circuit S2 is connected to the thermoelectric conversion circuit S1. The control method also includes: controlling the thermoelectric conversion circuit to convert the internal heat energy of the motor into electric energy, and then delivering the converted electric energy to the electric energy storage circuit for storage. That is, in the motor standby mode (under low temperature conditions) or the motor working mode, controlling the thermoelectric conversion circuit S1 to convert the internal heat energy of the motor into electric energy, and then delivering the converted electric energy to the electric energy storage circuit S2 for storage. For example, in the motor working mode, the MCU outputs a PWM signal 2 to the thermoelectric conversion circuit S1 to reduce the motor temperature, and at the same time collects energy to the electric energy storage circuit S2 to recover energy.

[0085] Optionally, the method further includes: receiving a prompt message from the electric energy storage circuit that the stored electricity has exceeded a preset electricity storage threshold; when receiving a prompt message from the electric energy storage circuit that the stored electricity has exceeded the preset electricity storage threshold, controlling the hot spot conversion circuit to stop converting the internal heat energy of the motor into electric energy. That is, the electric energy storage circuit is also used to: when the stored electricity has exceeded the preset electricity storage threshold, feedback a prompt message that the stored electricity has exceeded the preset electricity storage threshold; for example, the electric energy storage circuit feeds back the stored electricity Q to the MCU, and when the stored electricity Q exceeds the electricity storage threshold Q1, the MCU stops outputting the PWM signal 2.

[0086] Optionally, the method further includes: in the motor standby mode, when it is identified that the motor is in a low temperature condition, the heating circuit is powered by the electric energy storage circuit, so as to control the heating circuit to generate heat. That is, the heating circuit S4 is powered by the electric energy storage circuit S2, which reduces the additional power supply and improves the energy utilization rate. The electric energy storage circuit S2 is connected to the heating circuit S4 to power the heating circuit. The heating circuit S4 starts to work when it receives the PWM signal 1.

[0087] Optionally, the motor further includes: a standby charging circuit S3, which is connected to the electric energy storage circuit S2 and is used to provide electric energy to the electric energy storage circuit S2 for charging in the motor standby mode; the control method further includes: controlling the standby charging circuit to provide electric energy to the electric energy storage circuit for charging in the motor standby mode. For example, the MCU outputs a PWM signal 3 to the standby charging circuit S3 in the standby state, and the standby charging circuit operates at low power to trickle charge the electric energy storage circuit S2.

[0088] Figure 5 It is a method schematic diagram of another embodiment of the motor temperature control method provided by the present invention.

[0089] like Figure 5 As shown, according to another embodiment of the present invention, the motor temperature control method further includes step S130.

[0090] Step S130, adjusting the operation limit of the motor according to the internal temperature of the motor detected by the temperature detection circuit.

[0091] The operation restriction includes at least one of: motor current restriction, motor starting current, motor starting mode, motor speed restriction and motor power restriction. Specifically, when the motor is in a low temperature state and a high temperature state, the operation restriction of the motor is adjusted according to the detected internal temperature of the motor, wherein the operation restriction of the motor is adjusted in the low temperature state and the high temperature state, respectively, in the following manners:

[0092] A. When the motor is in low temperature state:

[0093] (1) When it is identified that the motor is in a low temperature state, when the detected internal temperature of the motor is less than a second preset temperature threshold, the current limiting value of the motor is increased by a first preset current value; wherein, when the detected internal temperature of the motor is less than a sixth preset temperature threshold (i.e., the preset low temperature threshold), it is identified that the motor is in a low temperature state.

[0094] Specifically, the MCU detects the temperature signal T and the sixth preset temperature threshold T0 and the first preset temperature threshold T1. When the temperature T is less than the threshold T0, the MCU identifies that the motor is in a low temperature state. When the temperature T is greater than the threshold T1, the MCU identifies that the motor is in a high temperature state. When the motor is in a low temperature state, the temperature T is compared with the second preset temperature threshold T2, the fourth preset temperature threshold T4 and the fifth preset temperature threshold T5. The size relationship of the three temperature thresholds is: T2>T4>T5, and each temperature threshold corresponds to a restriction release. When the temperature T is less than the threshold T2, the motor current limit is released, the motor current limit is increased, and the motor can run at a larger current.

[0095] (2) when the detected internal temperature of the motor is less than a fourth preset temperature threshold, increasing the current limit value of the motor by the first preset current value and increasing the starting current of the motor by the second preset current value;

[0096] Specifically, when the temperature T is less than the threshold value T4, the temperature is relatively low. To ensure the reliability of low-temperature starting, the motor current limit is increased while also increasing the motor starting current. A larger starting current can provide a larger starting torque. For example, more than two starting currents are set. When the motor starting current needs to be increased, the motor is started with a starting current that is larger than the current starting current.

[0097] (3) When the detected internal temperature of the motor is lower than a fifth preset temperature threshold, the current limit value of the motor is increased by a first preset current value, the starting current of the motor is increased by a second preset current value, and the starting mode of the motor is switched.

[0098] Specifically, when the temperature T is less than the threshold value T5, the motor starting mode (square wave drive) is switched on the basis of increasing the motor current limit value and the motor starting current, and the motor is driven to start at low temperature with a larger starting torque. Among them, different internal temperatures of the motor correspond to different initial values ​​of the starting torque, and the initial value of the starting torque corresponding to the internal temperature of the motor when it is less than the fifth preset temperature threshold is greater than the initial value of the starting torque corresponding to the internal temperature of the motor when it is greater than or equal to the fifth preset temperature threshold, that is, when the internal temperature of the motor is less than the fifth preset temperature threshold, the motor is driven to start at low temperature with a larger starting torque.

[0099] B. When the motor is at high temperature:

[0100] (1) When it is identified that the motor is in a high temperature state, when the detected internal temperature of the motor is greater than a third preset temperature threshold, the current of the motor is limited according to a preset current limiting value; wherein, when the detected internal temperature of the motor is greater than a first preset temperature threshold (i.e., the preset high temperature threshold), it is identified that the motor is in a high temperature state.

[0101] Specifically, the MCU detects the temperature signal T and the sixth preset temperature threshold T0 and the first preset temperature threshold T1. When the temperature T is less than the threshold T0, the MCU identifies that the motor is in a low temperature state. When the temperature T is greater than the threshold T1, the MCU identifies that the motor is in a high temperature state.

[0102] When the motor is in a high temperature state, the temperature T is compared with a third preset temperature threshold T3. When the temperature T>threshold T3, the motor current is limited according to a preset current limiting value.

[0103] (2) When the current of the motor is limited according to the preset current limiting value for a first preset time t1, if the internal temperature of the motor detected again is greater than a third preset temperature threshold, the speed limitation of the motor is executed; otherwise, the current limitation of the motor is released.

[0104] Specifically, when the temperature T>threshold T3, the motor current is limited according to the preset current limiting value, and timing t is started at the same time. When the time t accumulates to the preset value t1, the relationship between the temperature T and the threshold T3 is judged again. When the temperature T≤threshold T3, it means that the motor temperature has dropped, and the motor current limit is canceled at this time. When the temperature T>threshold T3, it means that the motor temperature has not yet dropped to the set value. At this time, on the basis of limiting the motor current, the motor speed is additionally limited, that is, the speed limit of the motor is executed. For example, when the motor speed exceeds the preset speed value, the motor current is reduced. That is, when the speed value exceeds the preset speed value, the current setting value is reduced, thereby reducing the motor current and reducing the motor speed.

[0105] (3) When the time for executing the speed limit of the motor reaches the second preset time t2, if the internal temperature of the motor detected again is greater than the third preset temperature threshold, the power limit of the motor is executed; otherwise, the current limit and the speed limit of the motor are released.

[0106] Specifically, the timing starts while the speed limit of the motor is executed. When the time t accumulates to the preset value t2, the relationship between the temperature T and the threshold value T3 is judged again. When the temperature T≤threshold value T3, it means that the motor temperature has dropped. At this time, the motor current limit and the speed limit are cancelled. When the temperature T>threshold value T3, it means that the motor temperature has not dropped to the set value. At this time, on the basis of limiting the motor current and limiting the motor speed, the motor power is additionally limited. For example, the motor current and voltage are detected in real time, and the real-time power of the motor is calculated. When the motor power protection is triggered, the motor voltage and current are limited. That is, the set values ​​of the motor voltage and current are set to fixed values, the motor voltage and current are limited, and the power is maintained unchanged.

[0107] The present invention also provides a storage medium corresponding to the motor temperature control method, on which a computer program is stored. When the computer program is executed by a processor, the steps of any of the above-mentioned motor temperature control methods are implemented.

[0108] The present invention also provides a motor controller corresponding to the motor temperature control method, including a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor implements any of the steps of the aforementioned motor temperature control method when executing the computer program.

[0109] The present invention also provides a motor corresponding to the motor temperature control system, comprising any of the above-mentioned motor temperature control systems.

[0110] The present invention also provides a computer program product corresponding to the motor temperature control method, comprising a computer program, and when the computer program is executed by a processor, the steps of any of the above-mentioned motor temperature control methods are implemented.

[0111] Accordingly, the solution provided by the present invention controls the thermoelectric conversion circuit or the heating circuit according to the working condition of the motor, dynamically adjusts the internal temperature of the motor, ensures that the internal temperature of the motor is within a suitable temperature range, and improves the reliability of the motor. The motor working conditions are distinguished according to the collected temperature data, and the protection limits of the motor are dynamically adjusted according to the different working conditions. High temperature increases the motor limits to limit the motor performance and protect the motor safety; low temperature removes the motor limits to improve the reliability of the motor start-up operation. Triple high temperature limits and triple low temperature limits are set, and different limits are added as the temperature increases, and different limits are removed as the temperature decreases.

[0112] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored as one or more instructions or codes on a computer-readable medium or transmitted via a computer-readable medium. Other examples and implementations are within the scope and spirit of the present invention and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these. In addition, each functional unit may be integrated into a processing unit, each unit may exist physically separately, or two or more units may be integrated into one unit.

[0113] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0114] The units described as separate components may or may not be physically separated, and the components of the control device may or may not be physical units, that is, they may be located in one place or distributed in multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0115] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the relevant technology or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk and other media that can store program codes.

[0116] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the claims of the present invention.

Claims

1. A motor temperature control system, characterized in that: include: Temperature detection circuit, used to detect the internal temperature of the motor; Thermoelectric conversion circuit, used to convert thermal energy into electrical energy to reduce the internal temperature of the motor; A heating circuit is used to generate heat to increase the internal temperature of the motor; The control unit is used to obtain the internal temperature of the motor detected by the temperature detection circuit, and control the thermoelectric conversion circuit and / or the heating circuit according to the internal temperature of the motor to adjust the internal temperature of the motor.

2. The motor temperature control system according to claim 1, characterized in that: The control unit controls the thermoelectric conversion circuit and / or the heating circuit according to the internal temperature of the motor to adjust the internal temperature of the motor, including: In the motor standby mode, when it is identified that the motor is in a high temperature condition, the thermoelectric conversion circuit is controlled to convert the internal heat energy of the motor into electrical energy to reduce the internal temperature of the motor; when it is identified that the motor is in a low temperature condition, the heating circuit is controlled to generate heat to increase the internal temperature of the motor; When the internal temperature of the motor detected by the temperature detection circuit is lower than a preset low temperature threshold, the motor is identified as being in a low temperature condition; when the internal temperature of the motor detected by the temperature detection circuit is higher than a preset high temperature threshold, the motor is identified as being in a low temperature condition; In the motor working mode, the thermoelectric conversion circuit is controlled to convert the internal thermal energy of the motor into electrical energy to reduce the internal temperature of the motor.

3. The motor temperature control system according to claim 1, characterized in that: Also includes: An electric energy storage circuit for storing electric energy; The control unit is further used to: control the thermoelectric conversion circuit to convert the internal heat energy of the motor into electrical energy, and then transmit the converted electrical energy to the electrical energy storage circuit for storage; In the motor standby mode, when it is identified that the motor is in a low temperature condition, the heating circuit is powered by the electric energy storage circuit, thereby controlling the heating circuit to generate heat.

4. The motor temperature control system according to claim 3, characterized in that: Also includes: A standby charging circuit is used to provide electric energy to the electric energy storage circuit for charging in the motor standby mode; The control unit is also used to: control the standby charging circuit to provide electric energy to the electric energy storage circuit for charging in the motor standby mode.

5. The motor temperature control system according to any one of claims 1 to 4, characterized in that: The control unit is further used for: According to the internal temperature of the motor detected by the temperature detection circuit, the operation limit of the motor is adjusted, and the operation limit includes: at least one of current limit, starting current, starting mode, speed limit and power limit.

6. The motor temperature control system according to claim 5, characterized in that: The control unit adjusts the operation limit of the motor according to the internal temperature of the motor detected by the temperature detection power, including: When it is identified that the motor is in a low temperature state, when the detected internal temperature of the motor is less than a second preset temperature threshold, the current limit value of the motor is increased by a first preset current value; wherein, when the detected internal temperature of the motor is less than a sixth preset temperature threshold, it is identified that the motor is in a low temperature state; When it is identified that the motor is in a high temperature state, when the detected internal temperature of the motor is greater than a third preset temperature threshold, the current of the motor is limited according to a preset current limiting value; wherein, when the detected internal temperature of the motor is greater than a first preset temperature threshold, it is identified that the motor is in a high temperature state.

7. The motor temperature control system according to claim 6, characterized in that: The control unit is further used for: When the detected internal temperature of the motor is less than a fourth preset temperature threshold, the current limit value of the motor is increased by the first preset current value, and the starting current of the motor is increased by the second preset current value; and / or, When the detected internal temperature of the motor is less than a fifth preset temperature threshold, the current limit value of the motor is increased by a first preset current value, the starting current of the motor is increased by a second preset current value, and the starting mode of the motor is switched.

8. The motor temperature control system according to claim 6, characterized in that: The control unit is further used for: When the current of the motor is limited according to the preset current limiting value for a first preset time, if the internal temperature of the motor detected again is greater than a third preset temperature threshold, the speed limitation of the motor is executed; otherwise, the current limitation of the motor is released.

9. The motor temperature control system according to claim 8, characterized in that: The control unit is further used for: When the time for executing the speed limit of the motor reaches a second preset time, if the internal temperature of the motor detected again is greater than a third preset temperature threshold, the power limit of the motor is executed, otherwise, the current limit and speed limit of the motor are released.

10. A method for controlling the temperature of a motor, characterized in that: The motor comprises: a temperature detection circuit for detecting the internal temperature of the motor; a thermoelectric conversion circuit for converting thermal energy into electrical energy to reduce the internal temperature of the motor; a heating circuit for generating heat to increase the internal temperature of the motor; and the motor temperature control method comprises: Acquiring the internal temperature of the motor detected by the temperature detection circuit; The thermoelectric conversion circuit and / or the heating circuit are controlled according to the internal temperature of the motor to adjust the internal temperature of the motor.

11. The method according to claim 10, characterized in that Also includes: The operation limit of the motor is adjusted according to the internal temperature of the motor detected by the temperature detection circuit, and the operation limit includes: at least one of motor current limit, motor starting current, motor starting mode, motor speed limit and motor power limit.

12. The method according to claim 11, characterized in that Adjusting the operation limit of the motor according to the internal temperature of the motor detected by the temperature detection circuit includes: When it is identified that the motor is in a low temperature state, when the detected internal temperature of the motor is less than a second preset temperature threshold, the current limit value of the motor is increased by a first preset current value; wherein, when the detected internal temperature of the motor is less than a sixth preset temperature threshold, it is identified that the motor is in a low temperature state; When it is identified that the motor is in a high temperature state, when the detected internal temperature of the motor is greater than a third preset temperature threshold, the current of the motor is limited according to a preset current limiting value; wherein, when the detected internal temperature of the motor is greater than a first preset temperature threshold, it is identified that the motor is in a high temperature state.

13. The method according to claim 12, characterized in that Also includes: When the detected internal temperature of the motor is less than a fourth preset temperature threshold, the current limit value of the motor is increased by the first preset current value, and the starting current of the motor is increased by the second preset current value; and / or, When the detected internal temperature of the motor is less than a fifth preset temperature threshold, the current limit value of the motor is increased by a first preset current value, the starting current of the motor is increased by a second preset current value, and the starting mode of the motor is switched.

14. The method according to claim 12, characterized in that Also includes: When the current of the motor is limited according to the preset current limiting value for a first preset time, if the internal temperature of the motor detected again is greater than a third preset temperature threshold, the speed limitation of the motor is executed; otherwise, the current limitation of the motor is released.

15. The method according to claim 14, characterized in that Also includes: When the time for executing the speed limit of the motor reaches the second preset time, if the internal temperature of the motor detected again is greater than the third preset temperature threshold, the power limit of the motor is executed, otherwise, the current limit and the speed limit of the motor are released.

16. A storage medium, characterized in that: A computer program is stored thereon, and when the program is executed by a processor, the steps of the method according to any one of claims 10 to 15 are implemented.

17. A controller for a motor, characterized in that: The method comprises a processor, a memory and a computer program stored in the memory and executable on the processor, wherein the steps of the method according to any one of claims 10 to 15 are implemented when the processor executes the program.

18. A motor, characterized in that: It comprises a motor temperature control system as described in any one of claims 1-9.

19. A computer program product, characterized in that The invention comprises a computer program, which implements the steps of the method according to any one of claims 10 to 15 when being executed by a processor.

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