Motor protection circuit and wind driven generator

Abstract

The application discloses a motor protection circuit and a wind driven generator, relates to the technical field of motor protection, and comprises a running control unit, a first end of the running control unit is connected with an environment signal voltage, a second end of the running control unit is connected with a running signal voltage, and the running control unit outputs a protection control voltage based on the environment signal voltage and the running signal voltage; a high-speed running protection unit, a first end of the high-speed running protection unit is connected with a third end of the running control unit, and the high-speed running protection unit is used for carrying out speed reduction protection based on the protection control voltage; and a low-speed running protection unit, a first end of the low-speed running protection unit is connected with a fourth end of the running control unit, and the low-speed running protection unit is used for carrying out speed increase protection based on the protection control voltage. The application improves the functionality of the motor protection circuit.

Description

Technical Field

[0001] This application relates to the field of motor protection technology, and in particular to a motor protection circuit and a wind turbine generator. Background Technology

[0002] With the increasing popularity of wind turbines, users have also placed higher demands on the design of motor protection circuits on wind turbines.

[0003] Traditional motor protection circuits are designed to trigger a corresponding motor protection mechanism when the wind speed exceeds a certain threshold. This design has certain drawbacks, as it relies solely on the wind speed exceeding a certain threshold as a judgment condition, resulting in a one-sided protection control and thus limited functionality of the motor protection circuit. Utility Model Content

[0004] The main purpose of this application is to provide a motor protection circuit and a wind turbine generator, aiming to solve the technical problem of low functionality of motor protection circuits.

[0005] To achieve the above objectives, this application provides a motor protection circuit, the motor protection circuit comprising: An operation control unit is provided, wherein a first terminal of the operation control unit is connected to an ambient signal voltage, a second terminal of the operation control unit is connected to an operation signal voltage, and the operation control unit outputs a protection control voltage based on the ambient signal voltage and the operation signal voltage. A high-speed operation protection unit, wherein the first end of the high-speed operation protection unit is connected to the third end of the operation control unit, and the high-speed operation protection unit is used to perform speed reduction protection based on the protection control voltage; A low-speed operation protection unit, wherein the first end of the low-speed operation protection unit is connected to the fourth end of the operation control unit, and the low-speed operation protection unit is used to perform speed-up protection based on the protection control voltage.

[0006] In one embodiment, the motor protection circuit further includes: A wind speed sensor is disposed at an external sensing position and is configured to output a high-level voltage when the wind speed is greater than a maximum threshold. A speed sensor is installed at the speed acquisition location of the motor. The speed sensor is used to acquire the actual speed of the motor and outputs a high level when the speed is greater than the maximum speed.

[0007] In one embodiment, the operation control unit includes: An AND gate device, wherein the first end of the AND gate device is connected to the wind speed sensor, and the second end of the AND gate device is connected to the speed sensor; An OR gate device is provided, wherein the first end of the OR gate device is connected to the third end of the AND gate device, the second end of the OR gate device is connected to the speed sensor, and the third end of the OR gate device is connected to the first end of the high-speed operation protection unit.

[0008] In one embodiment, the operation control unit includes: A first comparator, the first end of which is connected to a preset first value memory, the second end of which is connected to the speed sensor, and the third end of which is connected to the first end of the low-speed operation protection unit.

[0009] In one embodiment, the motor protection circuit further includes: A memory, the first end of which is connected to the speed sensor, is used to store the historical speed value of the previous moment; A subtractor, wherein the first end of the subtractor is connected to the second end of the memory, and the second end of the subtractor is connected to the speed sensor; A second comparator, the first end of which is connected to the third end of the subtractor, and the second end of which is connected to a preset second value memory; A constant speed control unit, wherein the first terminal of the constant speed control unit is connected to the third terminal of the second comparator.

[0010] In one embodiment, the speed averaging control unit includes: A power storage device is disposed at the upper end of the transmission component of the motor; A power release device, wherein the power release device is disposed at the lower end of the transmission component of the motor; A start-stop structure is provided, with one side of the start-stop structure disposed on the first side of the power storage device, the first side of the power storage device being the side near the upper end of the transmission component, and the other side of the start-stop structure disposed on the first side of the power release device, the first side of the power release device being the side near the lower end of the transmission component. The power supply terminal of the start-stop structure is connected to the third terminal of the second comparator.

[0011] In one embodiment, the high-speed operation protection unit includes: A high-level trigger, wherein the first terminal of the high-level trigger is connected to the third terminal of the operation control unit; A speed control component, wherein the control terminal of the speed control component is connected to the second terminal of the high-level trigger, and the speed control component is configured to limit the motor speed when a high level is received.

[0012] In one embodiment, the high-speed operation protection unit further includes: The first switching transistor has its third terminal connected to the third terminal of the operation control unit, and its first terminal connected to the power supply. A current limiter is installed on the line of the generator output terminal of the motor, and the control terminal of the current limiter is connected to the second terminal of the first switching transistor.

[0013] In one embodiment, the low-speed operation protection unit includes: The second switch is connected to the fourth terminal of the operation control unit, and the first terminal of the second switch is connected to the power supply. A blade drive motor, the first end of which is connected to the second end of the second switching tube, and the blade drive motor is mechanically connected to the blade of the wind turbine.

[0014] In addition, to achieve the above objectives, this application also provides a wind turbine generator, which includes the aforementioned motor protection circuit.

[0015] This application provides a motor protection circuit, including a running control unit. The first terminal of the running control unit is connected to an ambient signal voltage, and the second terminal is connected to a running signal voltage. The running control unit outputs a protection control voltage based on the ambient signal voltage and the running signal voltage. A high-speed running protection unit has its first terminal connected to the third terminal of the running control unit and is used for speed reduction protection based on the protection control voltage. A low-speed running protection unit has its first terminal connected to the fourth terminal of the running control unit and is used for speed increase protection based on the protection control voltage. This motor protection circuit outputs a protection control voltage based on the ambient signal voltage and the running signal voltage, and then provides the protection control voltage to the high-speed running protection unit or the low-speed running protection unit, thereby achieving speed increase or decrease control of the motor. This speed control extends protection for the motor at low speeds, avoiding the one-sidedness of relying solely on wind speed exceeding a certain threshold as a judgment condition. By providing the protection control voltage to the high-speed or low-speed running protection unit, speed increase or decrease control of the motor is achieved, thus improving the functionality of the motor protection circuit. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the framework of the first embodiment of the motor protection circuit of this application; Figure 2 This is a circuit diagram of the second embodiment of the motor protection circuit of this application; Figure 3 This is yet another circuit diagram of the second embodiment of the motor protection circuit of this application; Figure 4 This is a circuit diagram of the third embodiment of the motor protection circuit of this application; Figure 5 This is another circuit diagram of the third embodiment of the motor protection circuit of this application; Figure 6 This is a circuit diagram of the fourth embodiment of the motor protection circuit of this application.

[0017] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0018] Explanation of icon numbers: 10. Operation control unit; 20. High-speed operation protection unit; 30. Low-speed operation protection unit; V1. Ambient signal voltage; V2. Operation signal voltage; 41. Wind speed sensor; 42. Rotation speed sensor; 11. AND gate device; 12. OR gate device; 13. First comparator; 14. Preset first value memory; 51. Memory; 52. Subtractor; 53. Second comparator; 54. Preset second value memory; 70. Average speed control unit; 100. Transmission component; 71. Power memory; 72. Power release device; 73. Start limit structure; 74. Locking block; 21. High-level trigger; 22. Rotation speed control component; 31. First switching transistor; 32. Blade drive motor. Detailed Implementation

[0019] It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0020] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0021] The common practice in wind turbines is to protect the motor by triggering a corresponding motor protection mechanism when the wind speed exceeds a certain threshold. For example, to ensure that the motor's maximum output power is not too high, the motor speed is limited when the wind speed is high to ensure power generation. However, this method does not take into account situations where the wind speed is too low or the wind speed is uneven or sudden, resulting in a rather one-sided protection scenario for the motor.

[0022] Therefore, based on the shortcomings of the above motor protection circuits, the motor protection circuit of this application is proposed. The main solution of the embodiment of this application is: to output a protection control voltage based on the environmental signal voltage V1 and the operating signal voltage V2, and then to give the protection control voltage to the high-speed operation protection unit 20 or the low-speed operation protection unit 30, thereby realizing the speed increase or decrease control of the motor, that is, to control the speed increase or decrease from the speed aspect, so as to extend the protection of the motor at low speed, thereby avoiding the phenomenon that the protection control is relatively one-sided due to the wind speed exceeding a certain threshold as the judgment condition. That is, to give the protection control voltage to the high-speed operation protection unit 20 or the low-speed operation protection unit 30, thereby realizing the speed increase or decrease control of the motor, thereby improving the functionality of the motor protection circuit.

[0023] Based on this, the embodiments of this application provide a motor protection circuit, referring to... Figure 1 , Figure 1 This is a schematic diagram of the framework of the first embodiment of the motor protection circuit of this application.

[0024] Reference Figure 1 This application provides a motor protection circuit, which includes: The operation control unit 10 is connected to the first terminal of the operation control unit 10, the second terminal of the operation control unit 10 is connected to the operation signal voltage V2, and the operation control unit 10 outputs the protection control voltage based on the environmental signal voltage V1 and the operation signal voltage V2. High-speed operation protection unit 20, the first end of which is connected to the third end of operation control unit 10, is used for speed reduction protection based on protection control voltage; The low-speed operation protection unit 30 has its first terminal connected to the fourth terminal of the operation control unit 10. The low-speed operation protection unit 30 is used for speed-up protection based on the protection control voltage.

[0025] In this embodiment, to expand the motor protection scenarios, the environmental signal voltage V1 and the operating signal voltage V2 are combined to provide high-speed and low-speed operation protection based on these two signals. This is because it is necessary to consider not only the influence of external wind speed but also the internal rotational speed information to control the motor. The control methods include at least speed reduction protection and speed increase protection. For example, the environmental signal voltage V1 can be determined by collecting external wind speed data from relevant sensors and comparing it with a preset threshold. If the wind speed exceeds the threshold, a high level is output as the environmental signal voltage V1; otherwise, a low level is output. A comparator can be used for control, with its two inputs connected to the wind speed sensor and the set threshold output device, respectively. The output value of the threshold output device is compared with the value from the wind speed sensor, thus determining whether the environmental signal voltage V1 outputs a high or low level. For example, the operating signal voltage V2 can also be used to process the collected motor speed value in the above manner to determine whether the motor speed value exceeds a user-defined threshold. The sensor used to collect the motor speed can be a commonly used Hall sensor or other sensors, which are not limited here. After collecting the ambient signal voltage V1 and the operating signal voltage V2, they are processed in the operating control unit 10. Based on this, the operating control unit 10 can determine whether to use speed reduction protection or speed increase protection. Therefore, it can combine the ambient signal voltage V1 and the operating signal voltage V2 to control the motor in different scenarios to ensure its functionality.

[0026] In one embodiment, when the protection control voltage is applied to the high-speed operation protection unit 20, the high-speed operation protection unit 20 will know that the rotational speed is too high and will then perform speed reduction protection on the motor. This speed reduction protection can be achieved by using specific speed-reducing components to reduce the speed, thus preventing damage to the motor and its corresponding generator circuit from high-speed operation. When the protection control voltage is applied to the low-speed operation protection unit 30, the low-speed operation protection unit 30 will know that the rotational speed is too low and will then perform speed-up protection on the motor. This speed-up protection can be achieved by using specific speed-up components to reduce the speed, thus preventing damage to the motor and its corresponding generator circuit from low-speed operation. The problems with low-speed operation are generally related to power generation efficiency, and sudden changes in low speed can cause excessive changes in motor speed, affecting the motor. Therefore, the motor can be increased in speed. This can be achieved by adjusting the blade angle to increase the wind-receiving area and thus increase the motor speed. Therefore, the entire motor protection process can be based on both low-speed and high-speed scenarios, thereby expanding the functionality of the motor protection circuit.

[0027] In this embodiment, a motor protection circuit is provided, including a running control unit 10. The first terminal of the running control unit 10 is connected to an ambient signal voltage V1, and the second terminal is connected to a running signal voltage V2. The running control unit 10 outputs a protection control voltage based on the ambient signal voltage V1 and the running signal voltage V2. A high-speed running protection unit 20 is provided, with its first terminal connected to the third terminal of the running control unit 10. The high-speed running protection unit 20 is used for speed reduction protection based on the protection control voltage. A low-speed running protection unit 30 is provided, with its first terminal connected to the fourth terminal of the running control unit 10. The low-speed running protection unit 30 is used for... This motor protection circuit uses a protection control voltage to provide speed-up protection. It outputs a protection control voltage based on the ambient signal voltage V1 and the operating signal voltage V2, and then provides this voltage to the high-speed operation protection unit 20 or the low-speed operation protection unit 30. This enables speed-up or speed-down control of the motor, extending protection at low speeds. This avoids the one-sided nature of protection control caused by relying solely on wind speed exceeding a certain threshold. By providing the protection control voltage to the high-speed operation protection unit 20 or the low-speed operation protection unit 30, the circuit improves the functionality of the motor protection circuit.

[0028] Furthermore, based on the first embodiment of this application described above, a second embodiment of the motor protection circuit of this application is proposed, referring to... Figure 2 , Figure 2 This is a circuit diagram of the second embodiment of the motor protection circuit of this application. The motor protection circuit also includes: Wind speed sensor 41 is located at an external sensing position and is configured to output a high-level voltage when the wind speed is greater than the maximum threshold. The speed sensor 42 is set at the speed acquisition position of the motor. The speed sensor 42 is used to acquire the actual speed of the motor and output a high level when the speed is greater than the maximum speed.

[0029] Furthermore, the operation control unit 10 includes: AND gate device 11, the first end of AND gate device 11 is connected to wind speed sensor 41, and the second end of AND gate device 11 is connected to speed sensor 42; OR gate device 12, the first end of OR gate device 12 is connected to the third end of AND gate device 11, the second end of OR gate device 12 is connected to speed sensor 42, and the third end of OR gate device 12 is connected to the first end of high-speed operation protection unit 20.

[0030] In this embodiment, the motor protection circuit includes a wind speed sensor 41, which is located at an external sensing position, such as the location on the wind turbine's external sensing wind level, or a certain position on the casing. The wind speed sensor 41 is configured to output a high-level voltage when the wind speed exceeds a maximum threshold. This can be achieved through comparator-based output control, or by directly using a diode that conducts when the anode level is high; these methods will not be elaborated upon here. For example, the data acquisition device also includes a speed sensor 42, located at the motor speed acquisition position. The speed sensor 42 acquires the actual motor speed and outputs a high-level voltage when the speed exceeds the maximum speed, for example, outputting a high-level voltage when the speed exceeds A. Its internal circuit control can be the same as the control logic of the wind speed sensor 41, and will not be elaborated upon here.

[0031] In one embodiment, the operation control unit 10 includes a high-speed detection circuit. This circuit primarily detects whether the internal speed is greater than a set speed, mainly relying on the internal speed, but also considering the external speed. This is because excessively high internal speeds may be due to inertia, thus the judgment is made in conjunction with the internal speed. For example, the entire high-speed detection method can use an AND gate device 11. The AND gate device 11 is set to output a high level when both levels are high, meaning that both the internal and external speeds are greater than their respective preset values. The two preset values ​​can be the same or different. The result of the AND gate device 11 is then fed to an OR gate device 12, which is set to output a high level when one level is high, allowing for triggering using a higher internal rotation speed alone. Therefore, the entire operation control unit 10 outputs a high level when at least both the internal and external speeds are greater than their respective preset values, or only the internal speed is greater than its preset value. This ensures the accuracy of speed limiting control at high speeds and avoids the problem of slowing down solely based on the external environment. In such cases, if the external wind speed continues to increase, the rotation speed may be continuously reduced by a single program, resulting in poor power generation.

[0032] In one embodiment, reference is made to Figure 3 , Figure 3 This is another circuit diagram of the second embodiment of the motor protection circuit of this application. The operation control unit 10 includes: The first comparator 13 has its first terminal connected to the preset first value memory 14, its second terminal connected to the speed sensor 42, and its third terminal connected to the first terminal of the low-speed operation protection unit 30.

[0033] In this embodiment, the operation control unit 10 includes a low-speed detection circuit. This circuit mainly detects whether the internal speed is less than a set speed. For example, it uses a first comparator 13 to compare the speed collected by the speed sensor 42. The comparison is based on the value in the preset first value memory 14. If the preset first value memory 14 is set to the value S1, then when the speed collected by the speed sensor 42 is less than S1, the third terminal of the first comparator 13 will output a specific level, such as a high level, to control the low-speed operation protection unit 30 to achieve speed increase. Of course, the entire control unit can also be composed of other configurations, which are not limited here.

[0034] In one embodiment, based on the first and / or second embodiments of this application described above, a third embodiment of the motor protection circuit of this application is proposed, with reference to... Figure 4 , Figure 4 This is a circuit diagram of the third embodiment of the motor protection circuit of this application. The motor protection circuit also includes: The memory 51 has its first end connected to the speed sensor 42. The memory 51 is used to store the historical speed value of the previous moment. Subtractor 52, the first end of subtractor 52 is connected to the second end of memory 51, and the second end of subtractor 52 is connected to speed sensor 42; The second comparator 52 has its first terminal connected to the third terminal of the subtractor 52, and its second terminal connected to the preset second value memory 54. The speed control unit 70 has its first terminal connected to the third terminal of the second comparator 52.

[0035] Furthermore, refer to Figure 5 , Figure 5 This is another circuit diagram of the third embodiment of the motor protection circuit of this application. The speed control unit 70 includes: A power storage device 71 is disposed at the upper end of the transmission component 100 of the motor; The power release device 72 is located at the lower end of the transmission component 100 of the motor; The start-stop structure 73 is provided on one side of the power storage device 71, which is located near the upper end of the transmission component 100. The other side of the start-stop structure 73 is provided on the first side of the power release device 72, which is located near the lower end of the transmission component 100. The power supply terminal of the start-stop structure 73 is connected to the third terminal of the second comparator 52.

[0036] In this embodiment, the motor protection circuit also includes a memory 51, which stores the historical rotational speed value from the previous moment. Alternatively, the historical rotational speed value can be directly retrieved, and then subtracted from the current rotational speed value collected by the speed sensor 42 using a subtractor 52 to obtain the changed rotational speed value. Other hardware can also be used for control, which will not be detailed here. Furthermore, after determining the changed rotational speed value, it is compared with a defined acceptable change value, i.e., the acceptable change value is stored in the preset second numerical memory 54, thereby preventing damage to the motor caused by drastic changes. For example, when a drastic change in motor speed is detected, the speed averaging control unit 70 is activated to eliminate the drastic speed change. For instance, the speed averaging control unit 70 can be activated or put into standby mode directly based on a high-level comparison. For example, when the second comparator 52 outputs a high level, the speed averaging control unit 70 is activated. For example, when the speed control unit 70 is started, its main operating principle is as follows: a power storage device 71 is located at the upper end of the transmission component 100 of the motor; a power release device 72 is located at the lower end of the transmission component 100 of the motor; and a start-limiting structure 73 is located on one side of the power storage device 71, which is near the upper end of the transmission component 100. The other side of the start-limiting structure 73 is located on the first side of the power release device 72, which is near the lower end of the transmission component 100. The power supply terminal of the start-limiting structure 73 is connected to the third terminal of the second comparator 52. (See reference...) Figure 5 , Figure 5 As shown in the diagram, when the speed is too high, the starting limit structure 73 on the power storage device 71 side is pulled down and separated from the locking block 74. The pressure of the starting limit structure 73 on the power storage device 71 side will cause the power storage device 71 to be pressed down, that is, the power storage device 71 (assuming it is a spring) is compressed. After it ends or is pressed to the lowest point, the starting limit structure 73 on the power storage device 71 side returns upward and enters the corresponding locking block 74 to complete the limit. When the speed is too slow, the starting limit structure 73 on the power release device 72 side is pulled down and separated from the locking block 74. The pressure of the starting limit structure 73 on the power release device 72 side will release the pressure previously stored in the power storage device 71, that is, the power storage device 71 (assuming it is a spring) extends to push the component on the starting limit structure 73 on the power release device 72 side to rotate faster. Then the starting limit structure 73 on the power release device 72 side returns upward and enters the corresponding locking block 74 to complete the limit. Of course, deceleration or acceleration can also be controlled as described above. The start-up limit structure 73 can be connected to the middle recessed position of the connecting blade of the transmission component 100, or it can be any other position that can drive the blade. This is not limited here.

[0037] In one embodiment, based on the first, second, and / or third embodiments of this application described above, a fourth embodiment of the motor protection circuit of this application is proposed, referring to... Figure 6 , Figure 6 This is a circuit diagram of the fourth embodiment of the motor protection circuit of this application. The high-speed operation protection unit 20 includes: A high-level trigger 21 is provided, with its first terminal connected to the third terminal of the operation control unit 10. The speed control component 22 is connected to the second terminal of the high-level trigger 21. The speed control component 22 is configured to limit the motor speed when a high level is received.

[0038] In this embodiment, the high-speed operation protection unit 20 further includes: The first switching transistor has its third terminal connected to the third terminal of the operation control unit 10, and its first terminal connected to the power supply. The current limiter (which can be a commonly used current limiting device, such as a current limiter that directly uses a resistor voltage divider) is installed on the line at the generator output terminal of the motor, and the control terminal of the current limiter is connected to the second terminal of the first switching transistor.

[0039] In this embodiment, the high-speed operation protection unit 20 mainly reduces the motor speed. For example, the high-speed operation protection unit 20 can be composed of a high-level trigger 21 and a speed control component 22. The high-level trigger 21 can be triggered by a high level, thereby outputting a control signal to the speed control component 22. When the speed control component 22 receives a high level, it limits the motor speed. The speed control component 22 can be a component such as a pitch angle or limit control, that is, a component that only needs to limit the speed. However, the speed control component 22 needs to be triggered by the high-level trigger 21. The specific composition of the speed control component 22 is not limited here. Furthermore, in order to protect the internal current of the motor, a first switching transistor can be designed. When it receives a high level output from the third terminal of the operation control unit 10, i.e., the third terminal of the OR gate device 12, it will control the first switching transistor to conduct, thereby supplying power to the current limiter. The current limiter will limit the current output by the motor to avoid damage to the subsequent circuits caused by the sudden increase in current during a sudden increase in wind speed, thereby ensuring the accuracy of motor control and the safety of subsequent power generation control.

[0040] In yet another embodiment, the low-speed operation protection unit 30 includes: The second switch 31 has its third terminal connected to the fourth terminal of the operation control unit 10, and its first terminal connected to the power supply. The blade drive motor 32 has its first end connected to the second end of the second switch tube 31, and the blade drive motor 32 is mechanically connected to the blade of the wind turbine.

[0041] In this embodiment, the low-speed operation protection unit 30 includes a second switch 31. After receiving a high-level signal from the fourth terminal of the operation control unit 10, the second switch 31 controls the blade drive motor 32 to move. Internally, the second switch 31 can control the blade drive motor 32 to move a certain distance upon receiving a single high-level signal. The blade drive motor 32 then determines the different angles the blades form to create different wind-receiving areas, thereby continuously changing the wind-receiving area to adjust the rotational speed. For example, a timer can be set at the third terminal of the second switch 31 to avoid continuous changes in the blade angle and to ensure the rotational speed stabilizes before making a judgment, thus improving the accuracy of motor control at low speeds.

[0042] Based on the above embodiments of the motor protection circuit, a wind turbine generator is proposed, which includes the aforementioned motor protection circuit.

[0043] In this embodiment, the wind turbine generator, through a motor protection circuit, outputs a protection control voltage based on the environmental signal voltage V1 and the operating signal voltage V2. This protection control voltage is then supplied to the high-speed operation protection unit 20 or the low-speed operation protection unit 30, thereby achieving speed-up or speed-down control of the motor. This speed-up or speed-down control extends protection for the motor at low speeds, avoiding the one-sidedness of relying solely on wind speed exceeding a certain threshold. By supplying the protection control voltage to the high-speed operation protection unit 20 or the low-speed operation protection unit 30, the motor's speed-up or speed-down control is achieved, thus improving the functionality of the motor protection circuit. Furthermore, the entire motor protection circuit ensures accurate normal operation and extends the motor's lifespan, thereby reducing power generation protection costs.

[0044] The above are only some embodiments of this application and do not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. A motor protection circuit, characterized in that, The motor protection circuit includes: An operation control unit is provided, wherein a first terminal of the operation control unit is connected to an ambient signal voltage, a second terminal of the operation control unit is connected to an operation signal voltage, and the operation control unit outputs a protection control voltage based on the ambient signal voltage and the operation signal voltage. A high-speed operation protection unit, wherein the first end of the high-speed operation protection unit is connected to the third end of the operation control unit, and the high-speed operation protection unit is used to perform speed reduction protection based on the protection control voltage; A low-speed operation protection unit, wherein the first end of the low-speed operation protection unit is connected to the fourth end of the operation control unit, and the low-speed operation protection unit is used to perform speed-up protection based on the protection control voltage.

2. The motor protection circuit as described in claim 1, characterized in that, The motor protection circuit also includes: A wind speed sensor is disposed at an external sensing position and is configured to output a high-level voltage when the wind speed is greater than a maximum threshold. A speed sensor is installed at the speed acquisition location of the motor. The speed sensor is used to acquire the actual speed of the motor and outputs a high level when the speed is greater than the maximum speed.

3. The motor protection circuit as described in claim 2, characterized in that, The operation control unit includes: An AND gate device, wherein the first end of the AND gate device is connected to the wind speed sensor, and the second end of the AND gate device is connected to the speed sensor; An OR gate device is provided, wherein the first end of the OR gate device is connected to the third end of the AND gate device, the second end of the OR gate device is connected to the speed sensor, and the third end of the OR gate device is connected to the first end of the high-speed operation protection unit.

4. The motor protection circuit as described in claim 2, characterized in that, The operation control unit includes: A first comparator, the first end of which is connected to a preset first value memory, the second end of which is connected to the speed sensor, and the third end of which is connected to the first end of the low-speed operation protection unit.

5. The motor protection circuit as described in claim 2, characterized in that, The motor protection circuit also includes: A memory, the first end of which is connected to the speed sensor, is used to store the historical speed value of the previous moment; A subtractor, wherein the first end of the subtractor is connected to the second end of the memory, and the second end of the subtractor is connected to the speed sensor; A second comparator, the first end of which is connected to the third end of the subtractor, and the second end of which is connected to a preset second value memory; A constant speed control unit, wherein the first terminal of the constant speed control unit is connected to the third terminal of the second comparator.

6. The motor protection circuit as described in claim 5, characterized in that, The speed control unit includes: A power storage device is disposed at the upper end of the transmission component of the motor; A power release device, wherein the power release device is disposed at the lower end of the transmission component of the motor; A start-stop structure is provided, with one side of the start-stop structure disposed on the first side of the power storage device, the first side of the power storage device being the side near the upper end of the transmission component, and the other side of the start-stop structure disposed on the first side of the power release device, the first side of the power release device being the side near the lower end of the transmission component. The power supply terminal of the start-stop structure is connected to the third terminal of the second comparator.

7. The motor protection circuit as described in claim 1, characterized in that, The high-speed operation protection unit includes: A high-level trigger, wherein the first terminal of the high-level trigger is connected to the third terminal of the operation control unit; A speed control component, wherein the control terminal of the speed control component is connected to the second terminal of the high-level trigger, and the speed control component is configured to limit the motor speed when a high level is received.

8. The motor protection circuit as described in claim 7, characterized in that, The high-speed operation protection unit also includes: The first switching transistor has its third terminal connected to the third terminal of the operation control unit, and its first terminal connected to the power supply. A current limiter is installed on the line of the generator output terminal of the motor, and the control terminal of the current limiter is connected to the second terminal of the first switching transistor.

9. The motor protection circuit as described in claim 1, characterized in that, The low-speed operation protection unit includes: The second switch is connected to the fourth terminal of the operation control unit, and the first terminal of the second switch is connected to the power supply. A blade drive motor, the first end of which is connected to the second end of the second switching tube, and the blade drive motor is mechanically connected to the blade of the wind turbine.

10. A wind turbine generator, characterized in that, The wind turbine includes the motor protection circuit described in any one of claims 1 to 9.

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