Switched reluctance motor system and rotational speed detection method

Abstract

The application discloses a switched reluctance motor system and a rotating speed detection method, and relates to the technical field of switched reluctance motors.The system comprises a switched reluctance motor, a controller, a first magnetic ring, a first magnetic ring support, a sensor plate, and a first signal processing circuit.The first magnetic ring is fixed on the outside of the first magnetic ring support, the first magnetic ring support is connected with the motor shaft of the switched reluctance motor, the first magnetic ring rotates coaxially with the rotor in the switched reluctance motor, the sensor plate is provided with an output interface, N first Hall sensors and the first signal processing circuit, the first Hall sensors are connected with the output interface through the first signal processing circuit, and the output interface is connected with the controller.The first Hall sensors detect the rotation of the first magnetic ring, obtain a first rotor position detection signal, and send the first rotor position detection signal to the controller through the output interface.The application is suitable for calculating the rotating speed of the switched reluctance motor and performing phase output control on the switched reluctance motor.

Description

Technical Field

[0001] This application relates to the field of switched reluctance motor technology, and in particular to a switched reluctance motor system and a speed detection method. Background Technology

[0002] With the development of power electronics and control technologies, switched reluctance motor (SRM) control technology has rapidly advanced. Controlling an SRM requires measuring the rotor position. Since sensorless technology is not yet mature, most SRMs on the market currently have integrated position sensors. These integrated position sensors are typically photoelectric switch position sensors. Their working principle involves setting multiple photoelectric switch position sensors based on the number of phases of the SRM. These sensors detect the rotation of the photoelectric sensor encoder disk to obtain the corresponding rotor position detection signal. The motor's rotational speed is then calculated based on the obtained rotor position detection signal, and the phase output of the SRM is controlled accordingly.

[0003] However, the detection of rotor position signals in switched reluctance motors using photoelectric switch sensors depends on the machining accuracy of the photoelectric sensor encoder disk. When the machining accuracy of the photoelectric sensor encoder disk is not high enough, the accuracy of the obtained rotor position detection signal will be low, resulting in low accuracy of the calculated motor speed and low accuracy of phase output control. This can lead to imbalance of phase currents in the switched reluctance motor, as well as problems such as large vibration and noise in the switched reluctance motor. Summary of the Invention

[0004] The purpose of this application is to provide a switched reluctance motor system and a speed detection method. The main objective is to accurately measure the rotor position of the switched reluctance motor, thereby improving the accuracy of calculating the speed of the switched reluctance motor and improving the accuracy of phase output control of the switched reluctance motor.

[0005] To address the aforementioned technical problems, this application provides the following technical solutions:

[0006] In a first aspect, this application provides a switched reluctance motor system, the system comprising:

[0007] A switched reluctance motor, wherein the switched reluctance motor is an N-phase switched reluctance motor, and the rotor in the switched reluctance motor is an M-pole rotor, where N and M are positive integers greater than 1;

[0008] Controller;

[0009] The first magnetic ring is fixed around the outside of the first magnetic ring support member. The first magnetic ring support member is connected to the motor shaft of the switched reluctance motor. The first magnetic ring rotates coaxially with the rotor in the switched reluctance motor. The first magnetic ring includes M N poles and M S poles, and the M N poles and M S poles alternate with each other. The first magnetic ring is a radially magnetized magnetic ring.

[0010] A sensor board is provided with an output interface, N first Hall sensors and a first signal processing circuit. The first Hall sensors are connected to the output interface through the first signal processing circuit. The output interface is connected to the controller. The sensor board is fixed to the motor end cover of the switched reluctance motor.

[0011] The first Hall sensor detects the rotation of the first magnetic ring to obtain a first rotor position detection signal, and sends the first rotor position detection signal to the controller through the output interface. The controller then calculates the rotational speed of the switched reluctance motor based on the multiple first rotor position detection signals, and controls the phase output of the switched reluctance motor based on the multiple first rotor position detection signals.

[0012] Optionally, the sensor board is further provided with N second Hall sensors and a second signal processing circuit, and the second Hall sensors are connected to the output interface through the second signal processing circuit;

[0013] The second Hall sensor detects the rotation of the first magnetic ring to obtain a second rotor position detection signal, and sends the second rotor position detection signal to the controller through the output interface. The controller then calculates the rotational speed of the switched reluctance motor based on the multiple first rotor position detection signals and the multiple second rotor position detection signals, and controls the phase output of the switched reluctance motor based on the multiple first rotor position detection signals and the multiple second rotor position detection signals.

[0014] Optionally, the system further includes:

[0015] The second magnetic ring is fixed around the outside of the second magnetic ring support member. The second magnetic ring support member is connected to the motor shaft of the switched reluctance motor. The second magnetic ring rotates coaxially with the rotor in the switched reluctance motor. The second magnetic ring contains X N poles and X S poles, with the X N poles and X S poles alternating. The second magnetic ring is a radially magnetized magnetic ring, and X is an integer multiple of M.

[0016] The sensor board is also provided with Y third Hall sensors and a third signal processing circuit. The third Hall sensors are connected to the output interface through the third signal processing circuit, where Y is a positive integer greater than or equal to 1.

[0017] The third Hall sensor detects the rotation of the second magnetic ring to obtain a third rotor position detection signal, and sends the third rotor position detection signal to the controller through the output interface. The controller calculates the rotational speed of the switched reluctance motor based on at least one of the third rotor position detection signals, and controls the phase output of the switched reluctance motor based on multiple first rotor position detection signals and at least one of the third rotor position detection signals.

[0018] Optionally, the sensor plate is arc-shaped, the sensor plate surrounds the outside of the first magnetic ring, and the center of the sensor plate is at the same position as the center of the first magnetic ring;

[0019] N first Hall sensors are spaced apart on the sensor plate along the arc length direction of the sensor plate. The central angle corresponding to the arc length of the distance between two adjacent first Hall sensors on the sensor plate is K1*(360° / M)+360° / (M*N), where K1 is an integer greater than or equal to 0 and less than M.

[0020] N second Hall sensors are spaced apart on the sensor plate along the arc length direction of the sensor plate. The central angle corresponding to the arc length of the distance between two adjacent second Hall sensors on the sensor plate is K1*(360° / M)+360° / (M*N), where K1 is an integer greater than or equal to 0 and less than M.

[0021] The central angle corresponding to the arc length of the distance between each of the first Hall sensor and its corresponding second Hall sensor on the sensor plate is K2*(360° / M)+360° / (4*M), where K2 is an integer greater than or equal to 0 and less than M.

[0022] Optionally, a magnetic shielding plate is provided between the first magnetic ring and the second magnetic ring;

[0023] The sensor plate is arc-shaped and surrounds the outside of the first magnetic ring and the second magnetic ring. The center of the sensor plate is at the same position as the center of the first magnetic ring and the center of the second magnetic ring.

[0024] N first Hall sensors are spaced apart on the sensor plate along the arc length direction of the sensor plate. The central angle corresponding to the arc length of the distance between two adjacent first Hall sensors on the sensor plate is K1*(360° / M)+360° / (M*N), where K1 is an integer greater than or equal to 0 and less than M.

[0025] Y third Hall sensors are spaced apart on the sensor plate along the arc length direction of the sensor plate. The central angle corresponding to the arc length of the distance between two adjacent third Hall sensors on the sensor plate is K3*(360° / X)+360° / (Y*X), where K3 is an integer greater than or equal to 0 and less than X. N first Hall sensors and Y third Hall sensors are arranged side by side on the width direction of the sensor plate.

[0026] Secondly, this application also provides a speed detection method, which is applied to the above-mentioned switched reluctance motor system, and the method includes:

[0027] Receives first rotor position detection signals sent by multiple first Hall sensors;

[0028] A first transition edge waveform is generated based on multiple first rotor position detection signals;

[0029] Calculate the corresponding speed of the switched reluctance motor based on the waveform diagram of the first transition edge.

[0030] Optionally, one electrical angle period in the first rotor position detection signal is 360°, and the electrical angle period is specifically divided into A position count values; the calculation of the rotational speed corresponding to the switched reluctance motor based on the first transition edge waveform includes:

[0031] Based on the position count value corresponding to the first rising edge and the position count value corresponding to the first falling edge, the edge spacing value corresponding to the first transition edge waveform is determined, wherein the first rising edge and the first falling edge are any adjacent rising edge and falling edge in the first transition edge waveform.

[0032] The first timer is used to obtain the capture time corresponding to the first rising edge and the capture time corresponding to the first falling edge.

[0033] The capture period corresponding to the first transition edge waveform is determined based on the capture time corresponding to the first rising edge and the capture time corresponding to the first falling edge.

[0034] The rotational speed of the switched reluctance motor is calculated based on the edge spacing value, the capture period, and the preset rotational speed calculation constant.

[0035] Optionally, one electrical angle period in the first rotor position detection signal is 360°, and the electrical angle period is specifically divided into A position count values; after generating the first transition edge waveform based on the multiple first rotor position detection signals, the method further includes:

[0036] The system receives second rotor position detection signals sent by multiple second Hall sensors, wherein one electrical angle period of the second rotor position detection signal is 360°, and the electrical angle period is specifically divided into A position count values;

[0037] A second transition edge waveform is generated based on multiple second rotor position detection signals;

[0038] A third transition edge waveform is generated based on the first transition edge waveform and the second transition edge waveform.

[0039] The step of calculating the speed corresponding to the switched reluctance motor based on the waveform diagram of the first transition edge includes:

[0040] Based on the position count value corresponding to the second rising edge and the position count value corresponding to the second falling edge, the edge spacing value corresponding to the third transition edge waveform is determined, wherein the second rising edge and the second falling edge are any adjacent rising edge and falling edge in the third transition edge waveform.

[0041] The capture time corresponding to the second rising edge and the capture time corresponding to the second falling edge are obtained by the first timer;

[0042] The capture period corresponding to the third edge waveform is determined based on the capture time corresponding to the second rising edge and the capture time corresponding to the second falling edge.

[0043] The rotational speed of the switched reluctance motor is calculated based on the edge spacing value, the capture period, and the preset rotational speed calculation constant.

[0044] Optionally, one electrical angle period in the first rotor position detection signal is 360°, and the electrical angle period is specifically divided into A position count values; after generating the first transition edge waveform based on the multiple first rotor position detection signals, the method further includes:

[0045] Receive a third rotor position detection signal sent by at least one third Hall sensor;

[0046] A fourth transition edge waveform is generated based on at least one of the third rotor position detection signals;

[0047] The step of calculating the speed corresponding to the switched reluctance motor based on the waveform diagram of the first transition edge includes:

[0048] Based on the position count value corresponding to each rising edge and each falling edge in the first transition edge waveform diagram, determine the position count value corresponding to each rising edge and each falling edge in the fourth transition edge waveform diagram.

[0049] Based on the position count value corresponding to the third rising edge and the position count value corresponding to the third falling edge, the edge spacing value corresponding to the fourth transition edge waveform is determined, wherein the third rising edge and the third falling edge are any adjacent rising edge and falling edge in the fourth transition edge waveform.

[0050] The first timer is used to obtain the capture time corresponding to the third rising edge and the capture time corresponding to the third falling edge.

[0051] The capture period corresponding to the fourth edge waveform is determined based on the capture time corresponding to the third rising edge and the capture time corresponding to the third falling edge.

[0052] The rotational speed of the switched reluctance motor is calculated based on the edge spacing value, the capture period, and the preset rotational speed calculation constant.

[0053] Optionally, the method further includes:

[0054] Based on a preset time interval, the capture time and the current time corresponding to the first target edge are obtained by the second timer, wherein the first target edge is the rising edge or falling edge in the waveform diagram of the first transition edge that is closest to the current time.

[0055] Obtain the motor rotation direction;

[0056] The current rotor position count value is calculated based on the position count value corresponding to the first target edge, the edge spacing value corresponding to the first transition edge waveform, the capture time corresponding to the first target edge, the current time, the capture period corresponding to the first transition edge waveform, and the motor rotation direction.

[0057] The current rotor position count value is compared with the preset control parameters, and phase output control is performed based on the comparison result.

[0058] Optionally, the method further includes:

[0059] Based on a preset time interval, the capture time and the current time corresponding to the second target edge are obtained through the second timer, wherein the second target edge is the rising edge or falling edge in the waveform diagram of the third transition edge that is closest to the capture time and the current time.

[0060] Obtain the motor rotation direction;

[0061] The current rotor position count value is calculated based on the position count value corresponding to the second target edge, the edge spacing value corresponding to the third transition edge waveform, the capture time corresponding to the second target edge, the current time, the capture period corresponding to the third transition edge waveform, and the motor rotation direction.

[0062] The current rotor position count value is compared with the preset control parameters, and phase output control is performed based on the comparison result.

[0063] Optionally, the method further includes:

[0064] Based on a preset time interval, the capture time and the current time corresponding to the third target edge are obtained through the second timer. The third target edge is the rising edge or falling edge in the waveform diagram of the fourth transition edge that is closest to the capture time and the current time.

[0065] Obtain the motor rotation direction;

[0066] The current rotor position count value is calculated based on the position count value corresponding to the third target edge, the edge spacing value corresponding to the fourth transition edge waveform, the capture time corresponding to the third target edge, the current time, the capture period corresponding to the fourth transition edge waveform, and the motor rotation direction.

[0067] The current rotor position count value is compared with the preset control parameters, and phase output control is performed based on the comparison result.

[0068] By employing the above-described technical solution, the technical solution provided in this application has at least the following advantages:

[0069] This application provides a switched reluctance motor system and a speed detection method. Compared with the prior art, which obtains the rotor position detection signal of the switched reluctance motor by detecting the rotation of the photoelectric sensor code disk through multiple photoelectric switch position sensors, this application sets a first magnetic ring on the motor shaft of the switched reluctance motor. Multiple first Hall sensors mounted on a sensor plate detect the rotation of the first magnetic ring to obtain a first rotor position detection signal. The multiple first Hall sensors send the obtained first rotor position detection signal to a controller through an output interface. The controller then calculates the speed of the switched reluctance motor based on the multiple first rotor position detection signals and controls the phase output of the switched reluctance motor accordingly. Since the manufacturing process of the magnetic ring is relatively simple, the processing precision of the first magnetic ring can be ensured, thereby ensuring the high precision of the first rotor position detection signal obtained by the first Hall sensors. This improves the accuracy of calculating the switched reluctance motor speed and the accuracy of phase output control of the switched reluctance motor.

[0070] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0071] The above and other objects, features, and advantages of exemplary embodiments of this application will become readily understood by reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of this application are illustrated by way of example and not limitation, with the same or corresponding reference numerals denoteing the same or corresponding parts, wherein:

[0072] Figure 1 This paper shows a schematic diagram of a switched reluctance motor system according to an embodiment of the present application;

[0073] Figure 2 This illustration shows a structural schematic diagram of a first magnetic ring and a sensor board provided in an embodiment of this application;

[0074] Figure 3 This illustration shows a schematic diagram of another structure of the first magnetic ring and sensor board provided in an embodiment of this application;

[0075] Figure 4a This paper shows a schematic diagram of the structure of a sensor board provided in an embodiment of this application;

[0076] Figure 4b This paper shows a schematic diagram of the structure of a second magnetic ring according to an embodiment of the present application;

[0077] Figure 4c This paper shows a schematic diagram of another sensor board structure provided in an embodiment of this application;

[0078] Figure 5 A flowchart of a rotational speed detection method provided in an embodiment of this application is shown. Detailed Implementation

[0079] Exemplary embodiments of this application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of this application are shown in the drawings, it should be understood that this application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of this application and to fully convey the scope of this application to those skilled in the art.

[0080] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application shall have the ordinary meaning as understood by one of ordinary skill in the art to which this application pertains.

[0081] This application provides a switched reluctance motor system, such as... Figure 1 As shown, the system includes:

[0082] A switched reluctance motor 1, wherein the switched reluctance motor 1 is an N-phase switched reluctance motor, and the rotor of the switched reluctance motor 1 is an M-pole rotor, where N and M are positive integers greater than 1; a controller 2; a first magnetic ring 31, the first magnetic ring 31 being fixed around the outside of a first magnetic ring support 41, the first magnetic ring support 41 being connected to the motor shaft of the switched reluctance motor 1, the first magnetic ring 31 rotating coaxially with the rotor of the switched reluctance motor 1, wherein the first magnetic ring 31 contains M N poles and M S poles, the M N poles and M S poles alternating, the first magnetic ring 31 being a radially magnetized magnetic ring; a sensor board 5, the sensor board 5 being provided with an output interface 6 and N first Hall effect sensors. The sensor 71 and the first signal processing circuit 81 are connected. The first Hall sensor 71 is connected to the output interface 6 through the first signal processing circuit 81. The output interface 6 is connected to the controller 2. The sensor board 5 is fixed on the motor end cover of the switched reluctance motor 1. The first Hall sensor 71 obtains the first rotor position detection signal by detecting the rotation of the first magnetic ring 31, and sends the first rotor position detection signal to the controller 2 through the output interface 6. The controller 2 calculates the rotational speed of the switched reluctance motor 1 based on the multiple first rotor position detection signals, and controls the phase output of the switched reluctance motor 1 based on the multiple first rotor position detection signals.

[0083] The specific structure of the switched reluctance motor 1 can refer to the commonly used switched reluctance motor structure in the prior art. In this embodiment, the conventional parameters such as the number of phases, rotor poles, stator poles, volume, and power of the switched reluctance motor 1 are not specifically limited. Multiple first Hall sensors 71 are mounted on the sensor board 5. The multiple first Hall sensors 71 obtain the first rotor position detection signal by detecting the rotation of the first magnetic ring 31, and send the first rotor position detection signal to the controller 2 through the first signal processing circuit 81 and the output interface 6. The controller 2 can be a digital signal processor (DSP) or a microcontroller unit (MCU). After receiving the first rotor position detection signal sent by the multiple first Hall sensors 71, the controller 2 can, according to the multiple... The first rotor position detection signal generates a first transition edge waveform diagram. Based on the generated first transition edge waveform diagram, the rotational speed of the switched reluctance motor 1 is calculated, and the current rotor position of the switched reluctance motor 1 is determined based on the generated first transition edge waveform diagram. The phase output of the switched reluctance motor 1 is controlled according to the current rotor position of the switched reluctance motor 1. Specifically, the first signal processing circuit 81 is used to perform preset processing operations on the first rotor position detection signal acquired by the first Hall sensor 71, and then send the preset processed first rotor position detection signal to the controller 2 through the output interface 6. The preset processing operations performed by the first signal processing circuit 81 on the first rotor position detection signal may include, but are not limited to, signal filtering processing, signal amplification processing, etc.

[0084] Specifically, in this embodiment, when the switched reluctance motor 1 is a three-phase switched reluctance motor and its rotor is an 8-pole rotor, the structural diagram of the first magnetic ring 31 and the sensor board 5 can be as follows: Figure 2 As shown, the first magnetic ring 31 is fixed around the outside of the first magnetic ring support 41. The first magnetic ring 31 contains 8 N poles and 8 S poles, which alternate with each other. The sensor board 5 is provided with 3 first Hall sensors 71, a first signal processing circuit 81 and an output interface 6.

[0085] This application provides a switched reluctance motor system. Compared to existing technologies that use multiple photoelectric switch position sensors to detect the rotation of a photoelectric sensor code disk to obtain the rotor position detection signal of the switched reluctance motor, this application provides a first magnetic ring on the motor shaft of the switched reluctance motor. Multiple first Hall sensors mounted on a sensor plate detect the rotation of the first magnetic ring to obtain a first rotor position detection signal. These Hall sensors then send the obtained first rotor position detection signal to a controller via an output interface. The controller calculates the rotational speed of the switched reluctance motor based on the multiple first rotor position detection signals and controls the phase output of the switched reluctance motor accordingly. Because the manufacturing process of the magnetic ring is relatively simple, the processing precision of the first magnetic ring can be ensured, thereby ensuring the high precision of the first rotor position detection signal obtained by the first Hall sensors. This improves the accuracy of calculating the rotational speed of the switched reluctance motor and the accuracy of phase output control.

[0086] Furthermore, the sensor board 5 is also equipped with N second Hall sensors 72 and a second signal processing circuit 82. The second Hall sensors 72 are connected to the output interface 6 through the second signal processing circuit 82. The second Hall sensors 72 obtain the second rotor position detection signal by detecting the rotation of the first magnetic ring 31, and send the second rotor position detection signal to the controller 2 through the output interface 6. The controller 2 calculates the rotational speed of the switched reluctance motor 1 based on the multiple first rotor position detection signals and the multiple second rotor position detection signals, and controls the phase output of the switched reluctance motor 1 based on the multiple first rotor position detection signals and the multiple second rotor position detection signals. In this embodiment, multiple second Hall sensors 72 are mounted on the sensor board 5. These sensors detect the rotation of the first magnetic ring 31 to obtain a second rotor position detection signal, which is then sent to the controller 2 via the second signal processing circuit 82 and the output interface 6. Upon receiving the first rotor position detection signal from the multiple first Hall sensors 71 and the second rotor position detection signal from the multiple second Hall sensors 72, the controller 2 generates a first transition edge waveform based on the first rotor position detection signal and a second transition edge waveform based on the multiple second rotor position detection signals. Finally, it generates a third transition edge waveform based on the first and second transition edge waveforms. The system calculates the rotational speed of the switched reluctance motor 1 based on the generated third transition edge waveform, determines the current rotor position of the switched reluctance motor 1 based on the generated first and third transition edge waveforms, and controls the phase output of the switched reluctance motor 1 according to the current rotor position. Specifically, the second signal processing circuit 82 performs preset processing operations on the second rotor position detection signal acquired by the second Hall sensor 72, and then sends the pre-processed second rotor position detection signal to the controller 2 through the output interface 6. The preset processing operations performed by the second signal processing circuit 82 on the second rotor position detection signal may include, but are not limited to, signal filtering and signal amplification. It should be noted that in practical applications, the first signal processing circuit 81 and the second signal processing circuit 82 may be the same signal processing circuit or different signal processing circuits; this embodiment does not specifically limit this.Since the edge spacing between two adjacent rising and falling edges in the third transition edge waveform diagram is smaller than that between two adjacent rising and falling edges in the first transition edge waveform diagram, calculating the speed of the switched reluctance motor 1 based on the third transition edge waveform diagram and controlling the phase output of the switched reluctance motor 1 based on the first and third transition edge waveform diagrams—that is, calculating the speed of the switched reluctance motor 1 based on multiple first rotor position detection signals and multiple second rotor position detection signals, and controlling the phase output of the switched reluctance motor 1 based on multiple first rotor position detection signals and multiple second rotor position detection signals—can further improve the accuracy of calculating the speed of the switched reluctance motor 1 and the accuracy of controlling the phase output of the switched reluctance motor 1.

[0087] Furthermore, the sensor plate 5 is arc-shaped, surrounding the outside of the first magnetic ring 31, and the center of the sensor plate 5 is at the same position as the center of the first magnetic ring 31; wherein, N first Hall sensors 71 are spaced apart on the sensor plate 5 along the arc length direction, and the central angle corresponding to the arc length of the distance between two adjacent first Hall sensors 71 on the sensor plate 5 is K1*(360° / M)+360° / (M*N), where K1 is an integer greater than or equal to 0 and less than M; N second Hall sensors 72 The second Hall sensors 72 are spaced apart along the arc length of the sensor plate 5. The central angle corresponding to the arc length of the distance between two adjacent second Hall sensors 72 on the sensor plate 5 is K1*(360° / M)+360° / (M*N), where K1 is an integer greater than or equal to 0 and less than M. The central angle corresponding to the arc length of the distance between each first Hall sensor 71 and its corresponding second Hall sensor 72 on the sensor plate 5 is K2*(360° / M)+360° / (4*M), where K2 is an integer greater than or equal to 0 and less than M.

[0088] Specifically, in this embodiment, when the switched reluctance motor 1 is a three-phase switched reluctance motor, and its rotor is an 8-pole rotor, with K1=0 and K2=2, the structural diagram of the first magnetic ring 31 and the sensor board 5 can be as follows: Figure 3As shown, the first magnetic ring 31 is fixed around the outside of the first magnetic ring support 41. The first magnetic ring 31 contains 8 N poles and 8 S poles, which alternate. The sensor board 5 is equipped with 3 first Hall sensors 71 (first Hall sensor 71a, first Hall sensor 71b, and first Hall sensor 71c), a first signal processing circuit 81, 3 second Hall sensors 72 (second Hall sensor 72a, second Hall sensor 72b, and second Hall sensor 72c), a second signal processing circuit 82, and an output interface 6. The central angle corresponding to the arc length of the distance between two adjacent first Hall sensors 71 on the sensor board 5 is 0*(360° / 8)+360° / (3*8)=15°. The central angle corresponding to the arc length of the distance between the first Hall sensor 71a and the second Hall sensor 72a on the sensor plate 5 is 0*(360° / 8)+360° / (3*8)=15°. The central angle corresponding to the arc length of the distance between the first Hall sensor 71a and the second Hall sensor 72a on the sensor plate 5 is 2*(360° / 8)+360° / (4*8)=101.25°. The central angle corresponding to the arc length of the distance between the first Hall sensor 71b and the second Hall sensor 72b on the sensor plate 5 is 2*(360° / 8)+360° / (4*8)=101.25°. The central angle corresponding to the arc length of the distance between the first Hall sensor 71c and the second Hall sensor 72c on the sensor plate 5 is 2*(360° / 8)+360° / (4*8)=101.25°.

[0089] Furthermore, the switched reluctance motor system also includes: a second magnetic ring 32, which is fixed around the outside of the second magnetic ring support 42. The second magnetic ring support 42 is connected to the motor shaft of the switched reluctance motor 1. The second magnetic ring 32 rotates coaxially with the rotor in the switched reluctance motor 1. The second magnetic ring 32 contains X N poles and X S poles, which alternate. The second magnetic ring 32 is a radially magnetized magnetic ring, and X is an integer multiple of M. The sensor board 5 is also equipped with Y third Hall sensors 73 and a third signal processing circuit 83. Hall sensor 73 is connected to output interface 6 via third signal processing circuit 83, where Y is a positive integer greater than or equal to 1. The third Hall sensor 73 detects the rotation of the second magnetic ring 32 to obtain a third rotor position detection signal, and sends this signal to controller 2 via output interface 6. Controller 2 then calculates the rotational speed of the switched reluctance motor 1 based on at least one third rotor position detection signal, and controls the phase output of the switched reluctance motor 1 based on multiple first rotor position detection signals and at least one third rotor position detection signal. Specifically, in practical applications, the first magnetic ring 31 and the second magnetic ring 32 can be configured such that the plane containing any N / S pole junction of the first magnetic ring 31 and its corresponding N / S pole junction of the second magnetic ring 32 is parallel to the motor shaft of the switched reluctance motor 1, but this is not a limitation.

[0090] In this embodiment, at least one third Hall sensor 73 is disposed on the sensor board 5. The at least one third Hall sensor 73 obtains a third rotor position detection signal by detecting the rotation of the second magnetic ring 32, and sends the third rotor position detection signal to the controller 2 through the third signal processing circuit 83 and the output interface 6. After receiving the first rotor position detection signals sent by multiple first Hall sensors 71 and the third rotor position detection signal sent by at least one third Hall sensor 73, the controller 2 can generate a first transition edge waveform based on the multiple first rotor position detection signals and a fourth transition edge waveform based on the at least one third rotor position detection signal, and then, based on the generated fourth transition edge waveform... The rotational speed of the switched reluctance motor 1 is calculated along the waveform diagram, and the current rotor position of the switched reluctance motor 1 is determined based on the generated first and fourth transition edge waveform diagrams. The phase output of the switched reluctance motor 1 is then controlled according to the current rotor position. Specifically, the third signal processing circuit 83 performs preset processing operations on the third rotor position detection signal acquired by the third Hall sensor 73, and then sends the pre-processed third rotor position detection signal to the controller 2 through the output interface 6. The preset processing operations performed by the third signal processing circuit 83 on the third rotor position detection signal may include, but are not limited to, signal filtering and signal amplification. It should be noted that in practical applications, the first signal processing circuit 81 and the third signal processing circuit 83 may be the same signal processing circuit or different signal processing circuits; this embodiment does not specifically limit this. Since the edge spacing between two adjacent rising and falling edges in the fourth transition edge waveform diagram is smaller than that between two adjacent rising and falling edges in the first transition edge waveform diagram, calculating the speed of the switched reluctance motor 1 based on the fourth transition edge waveform diagram and controlling the phase output of the switched reluctance motor 11 based on the first and fourth transition edge waveform diagrams—that is, calculating the speed of the switched reluctance motor 1 based on at least one third rotor position detection signal and controlling the phase output of the switched reluctance motor 1 based on multiple first rotor position detection signals and at least one third rotor position detection signal—can further improve the accuracy of calculating the speed of the switched reluctance motor 1 and the accuracy of controlling the phase output of the switched reluctance motor 1.

[0091] Furthermore, a magnetic shielding plate is provided between the first magnetic ring 31 and the second magnetic ring 32; the sensor plate 5 is arc-shaped, surrounding the outside of the first magnetic ring 31 and the second magnetic ring 32, and the center of the sensor plate 5 is at the same position as the center of the first magnetic ring 31 and the center of the second magnetic ring 32; N first Hall sensors 71 are spaced apart on the sensor plate 5 along the arc length direction, and the central angle corresponding to the arc length of the distance between two adjacent first Hall sensors 71 on the sensor plate 5 is K1*(360° / M)+3 60° / (M*N), where K1 is an integer greater than or equal to 0 and less than M; Y third Hall sensors 73 are spaced apart on the sensor plate 5 along the arc length direction. The central angle corresponding to the arc length of the distance between two adjacent third Hall sensors 73 on the sensor plate 5 is = K3*(360° / X)+360° / (Y*X), where K3 is an integer greater than or equal to 0 and less than X. N first Hall sensors 71 are arranged side-by-side with the Y third Hall sensors 73 along the width direction of the sensor plate 5. Specifically, in practical applications, the straight line containing the center point of the first third Hall sensor 73 among the Y third Hall sensors 73 and the center point of the first first Hall sensor 71 among the N first Hall sensors 71 is parallel to the motor shaft of the switched reluctance motor 1, but is not limited to this.

[0092] Specifically, in the embodiments of this application, the structural schematic diagram of the sensor board 5 can be as follows: Figure 4a As shown, the sensor plate 5 includes six surfaces: an upper surface, a lower surface opposite to the upper surface, a left side surface, a right side surface opposite to the left side surface, an inner side surface, and an outer side surface opposite to the inner side surface. In practical applications, N first Hall sensors 71 can be disposed on the lower surface of the sensor plate 5, and Y third Hall sensors 73 can be disposed on the upper surface of the sensor plate 5. Alternatively, N first Hall sensors 71 and Y third Hall sensors 73 can be disposed on the inner side surface of the sensor plate 5. This application embodiment does not specifically limit this.

[0093] Specifically, in the embodiments of this application, when the switched reluctance motor 1 is a three-phase switched reluctance motor, and its rotor is an 8-pole rotor, the structural schematic diagram of the second magnetic ring 32 can be as follows: Figure 4b As shown, the second magnetic ring 32 is fixed around the outside of the second magnetic ring support 42. The second magnetic ring 32 contains 16 N poles and 16 S poles, which alternate. When three third Hall sensors 73 are installed on the sensor board 5, and K1 = 0 and K3 = 1, the structural diagram of the sensor board 5 can be shown as follows. Figure 4cAs shown, the inner side of the sensor board 5 is provided with three first Hall sensors 71 (first Hall sensor 71a, first Hall sensor 71b and first Hall sensor 71c), a first signal processing circuit 81, three third Hall sensors 73 (third Hall sensor 73a, third Hall sensor 73b and third Hall sensor 73c), a third signal processing circuit 83, and an output interface 6; wherein, the central angle corresponding to the arc length of the distance between two adjacent first Hall sensors 71 on the sensor board 5 is 0*(360° / 8)+360° / (3*8)=15°, and the central angle corresponding to the arc length of the distance between two adjacent third Hall sensors 73 on the sensor board 5 is (360° / 16)+360° / (3*16)=30°. The three first Hall sensors 71 and the three third Hall sensors 73 are arranged side by side in the width direction of the sensor board, and the straight line containing the center point of the third Hall sensor 73a and the center point of the first Hall sensor 71a is parallel to the motor shaft of the switched reluctance motor 1.

[0094] This application provides a speed detection method, which is applied to the aforementioned switched reluctance motor system, such as... Figure 5 As shown, the method includes:

[0095] 101. Receive the first rotor position detection signal sent by multiple first Hall sensors.

[0096] In this embodiment, the execution entity in each step is the controller in the switched reluctance motor system. Multiple first Hall sensors mounted on the sensor board detect the rotation of the first magnetic ring to obtain a first rotor position detection signal, and then send this signal to the controller via an output interface. At this point, the controller can receive the first rotor position detection signals sent by the multiple first Hall sensors.

[0097] 102. Generate the first transition edge waveform based on multiple first rotor position detection signals.

[0098] In this embodiment, after receiving first rotor position detection signals from multiple first Hall sensors, the controller can generate a first transition edge waveform based on the multiple first rotor position detection signals. Specifically, in this step, the controller can generate the first transition edge waveform by performing logical operations on the multiple first rotor position detection signals, but is not limited to this.

[0099] 103. Calculate the corresponding speed of the switched reluctance motor based on the waveform diagram of the first transition edge.

[0100] In this embodiment of the application, after the controller generates a first transition edge waveform based on multiple first rotor position detection signals, it can calculate the corresponding speed of the switched reluctance motor based on the generated first transition edge waveform.

[0101] Specifically, in this step, one electrical angle period in any first rotor position detection signal is 360°, and the electrical angle period is specifically divided into A position count values. The controller can calculate the speed corresponding to the switched reluctance motor based on the waveform diagram of the first transition edge in the following way: First, the controller determines the edge spacing value corresponding to the waveform diagram of the first transition edge based on the position count value corresponding to the first rising edge and the position count value corresponding to the first falling edge. That is, when the position count value corresponding to the first rising edge is greater than the position count value corresponding to the first falling edge, the position count value corresponding to the first rising edge is compared with the position count value corresponding to the first falling edge. The difference between the corresponding position count values ​​is determined as the edge spacing value corresponding to the first transition edge waveform. When the position count value corresponding to the first rising edge is less than the position count value corresponding to the first falling edge, the difference between the position count value corresponding to the first falling edge and the position count value corresponding to the first rising edge is determined as the edge spacing value corresponding to the first transition edge waveform. Here, the first rising edge and the first falling edge are any adjacent rising and falling edges in the first transition edge waveform. Then, the controller obtains the capture time corresponding to the first rising edge and the capture time corresponding to the first falling edge through the first timer. Next, the controller determines the capture period corresponding to the first transition edge waveform based on the capture time corresponding to the first rising edge and the capture time corresponding to the first falling edge. Specifically, when the capture time corresponding to the first rising edge is greater than the capture time corresponding to the first falling edge, the difference between the capture time corresponding to the first rising edge and the capture time corresponding to the first falling edge is determined as the capture period corresponding to the first transition edge waveform. When the capture time corresponding to the first rising edge is less than the capture time corresponding to the first falling edge, the difference between the capture time corresponding to the first falling edge and the capture time corresponding to the first rising edge is determined as the first transition edge waveform period. The capture period corresponding to the waveform diagram of the first transition edge; finally, the controller calculates the speed corresponding to the switched reluctance motor based on the edge spacing value corresponding to the waveform diagram of the first transition edge, the capture period corresponding to the waveform diagram of the first transition edge, and the preset speed calculation constant. That is, the edge spacing value corresponding to the waveform diagram of the first transition edge, the capture period corresponding to the waveform diagram of the first transition edge, and the preset speed calculation constant are substituted into the first preset formula to calculate the speed corresponding to the switched reluctance motor. The preset speed calculation constant is determined based on the number of motor phases N, the number of rotor poles M, and the position count value A corresponding to the switched reluctance motor. The first preset formula is as follows:

[0102] v = m * Kv / T

[0103] Where v is the rotational speed of the switched reluctance motor, m is the edge spacing value corresponding to the waveform of the first transition edge, Kv is the preset rotational speed calculation constant, and T is the capture period corresponding to the waveform of the first transition edge.

[0104] Furthermore, in this embodiment, after calculating the rotational speed of the switched reluctance motor based on the first transition edge waveform, the controller can also control the phase output of the switched reluctance motor based on the first transition edge waveform: based on a preset time interval, that is, every preset time interval, the second timer obtains the capture time and the current time corresponding to the first target edge, wherein the first target edge is the rising edge or falling edge in the first transition edge waveform where the capture time is less than the current time and the capture time is closest to the current time. The preset time interval can be, but is not limited to, 1ms, 3ms, 5ms, etc.; and obtains the motor rotation direction. Based on the position count value corresponding to the first target edge, the edge spacing value corresponding to the first transition edge waveform, the capture time corresponding to the first target edge, the current time, the capture period corresponding to the first transition edge waveform, and the motor rotation direction, the current rotor position count value is calculated. Specifically, when the motor rotation direction is positive, the position count value corresponding to the first target edge, the edge spacing value corresponding to the first transition edge waveform, the capture time corresponding to the first target edge, the current time, and the capture period corresponding to the first transition edge waveform are substituted into the second preset formula to calculate the current rotor position count value corresponding to the switched reluctance motor. The second preset formula is as follows:

[0105] Ai = An + m * (t1 - t2) / T

[0106] Where Ai is the current rotor position count value corresponding to the switched reluctance motor, An is the position count value corresponding to the first target edge, m is the edge spacing value corresponding to the first transition edge waveform, t1 is the current time, t2 is the capture time corresponding to the first target edge, and T is the capture period corresponding to the first transition edge waveform.

[0107] When the motor rotates in the opposite direction, the position count value corresponding to the first target edge, the edge spacing value corresponding to the first transition edge waveform, the capture time corresponding to the first target edge, the current time, and the capture period corresponding to the first transition edge waveform are substituted into the third preset formula to calculate the current rotor position count value corresponding to the switched reluctance motor. The third preset formula is as follows:

[0108] Ai = An - m * (t1 - t2) / T

[0109] Where Ai is the current rotor position count value corresponding to the switched reluctance motor, An is the position count value corresponding to the first target edge, m is the edge spacing value corresponding to the first transition edge waveform, t1 is the current time, t2 is the capture time corresponding to the first target edge, and T is the capture period corresponding to the first transition edge waveform. The current rotor position count value corresponding to the switched reluctance motor is compared with the preset control parameters, and phase output control is performed according to the comparison result. The preset control parameters may include, but are not limited to, the position count range corresponding to the preset turn-on angle and the position count range corresponding to the preset turn-off angle. How the controller performs phase output control on the switched reluctance motor according to the comparison result of the current rotor position count value corresponding to the switched reluctance motor and the preset control parameters can be referred to the existing related technologies, and will not be elaborated on in this embodiment.

[0110] Furthermore, in this embodiment, in addition to multiple first Hall sensors, the sensor board also has multiple second Hall sensors. The multiple first Hall sensors detect the rotation of the first magnetic ring to obtain a first rotor position detection signal, and send this signal to the controller via an output interface. Similarly, the multiple second Hall sensors detect the rotation of the first magnetic ring to obtain a second rotor position detection signal, and send this signal to the controller via an output interface. The controller can then receive both the first and second rotor position detection signals from the first and second Hall sensors. In any first rotor position detection signal, one electrical angle period is 360°, specifically divided into A position count values. Similarly, in any second rotor position detection signal, one electrical angle period is 360°, specifically divided into A position count values. After receiving both the first and second rotor position detection signals from the first and second Hall sensors, the controller can generate a first transition edge waveform based on the first rotor position detection signals and a second transition edge waveform based on the second rotor position detection signals. Then, based on the first... A third transition edge waveform is generated from a first-rising-edge waveform and a second-rising-edge waveform. Specifically, the controller can generate the first transition edge waveform by performing logical operations on multiple first rotor position detection signals, generate the second transition edge waveform by performing logical operations on multiple second rotor position detection signals, and generate the third transition edge waveform by performing logical operations on the first and second transition edge waveforms, but is not limited to these methods. After generating the third transition edge waveform, the controller can determine the time interval between the corresponding edges of the third transition edge waveform based on the position count values ​​corresponding to the second rising edge and the second falling edge. The distance value is defined as follows: when the position count value corresponding to the second rising edge is greater than the position count value corresponding to the second falling edge, the difference between the position count value corresponding to the second rising edge and the position count value corresponding to the second falling edge is determined as the edge spacing value corresponding to the third transition edge waveform. When the position count value corresponding to the second rising edge is less than the position count value corresponding to the second falling edge, the difference between the position count value corresponding to the second falling edge and the position count value corresponding to the second rising edge is determined as the edge spacing value corresponding to the third transition edge waveform. Here, the second rising edge and the second falling edge are any adjacent rising edge and falling edge in the third transition edge waveform.After determining the edge spacing value corresponding to the third transition edge waveform, the controller can obtain the capture time corresponding to the second rising edge and the second falling edge through the first timer. Based on the capture times of the second rising edge and the second falling edge, the controller determines the capture period corresponding to the third transition edge waveform. Specifically, when the capture time corresponding to the second rising edge is greater than the capture time corresponding to the second falling edge, the difference between the two capture times is determined as the capture period corresponding to the third transition edge waveform. When the capture time corresponding to the second rising edge is less than the capture time corresponding to the second falling edge, the difference between the two capture times is determined as the capture period corresponding to the third transition edge waveform. The difference between the capture time of the first rising edge and the capture time corresponding to the second rising edge is determined as the capture period corresponding to the third rising edge waveform. Finally, the controller can calculate the speed of the switched reluctance motor based on the edge spacing value, the capture period, and the preset speed calculation constant of the third rising edge waveform. That is, the edge spacing value, the capture period, and the preset speed calculation constant of the third rising edge waveform are substituted into the first preset formula to calculate the speed of the switched reluctance motor. The preset speed calculation constant is determined based on the number of motor phases N, the number of rotor poles M, and the position count value A of the switched reluctance motor. The first preset formula is as follows:

[0111] v = m * Kv / T

[0112] Where v is the rotational speed of the switched reluctance motor, m is the edge spacing value corresponding to the waveform diagram of the third transition edge, Kv is the preset rotational speed calculation constant, and T is the capture period corresponding to the waveform diagram of the third transition edge.

[0113] Furthermore, in this embodiment, after calculating the rotational speed of the switched reluctance motor based on the third transition edge waveform, the controller can also control the phase output of the switched reluctance motor based on the third transition edge waveform: based on a preset time interval, that is, every preset time interval, the second timer obtains the capture time and the current time corresponding to the second target edge, wherein the second target edge is the rising edge or falling edge in the third transition edge waveform where the capture time is less than the current time and the capture time is closest to the current time. The preset time interval can be, but is not limited to, 1ms, 3ms, 5ms, etc.; and obtains the motor rotation direction. Based on the position count value corresponding to the second target edge, the edge spacing value corresponding to the third transition edge waveform, the capture time corresponding to the second target edge, the current time, the capture period corresponding to the third transition edge waveform, and the motor rotation direction, the current rotor position count value is calculated. Specifically, when the motor rotation direction is positive, the position count value corresponding to the second target edge, the edge spacing value corresponding to the third transition edge waveform, the capture time corresponding to the second target edge, the current time, and the capture period corresponding to the third transition edge waveform are substituted into the second preset formula to calculate the current rotor position count value corresponding to the switched reluctance motor. The second preset formula is as follows:

[0114] Ai = An + m * (t1 - t2) / T

[0115] Where Ai is the current rotor position count value corresponding to the switched reluctance motor, An is the position count value corresponding to the second target edge, m is the edge spacing value corresponding to the third transition edge waveform, t1 is the current time, t2 is the capture time corresponding to the second target edge, and T is the capture period corresponding to the third transition edge waveform.

[0116] When the motor rotates in the opposite direction, the position count value corresponding to the second target edge, the edge spacing value corresponding to the third transition edge waveform, the capture time corresponding to the second target edge, the current time, and the capture period corresponding to the third transition edge waveform are substituted into the third preset formula to calculate the current rotor position count value corresponding to the switched reluctance motor. The third preset formula is as follows:

[0117] Ai = An - m * (t1 - t2) / T

[0118] Where Ai is the current rotor position count value corresponding to the switched reluctance motor, An is the position count value corresponding to the second target edge, m is the edge spacing value corresponding to the third transition edge waveform, t1 is the current time, t2 is the capture time corresponding to the second target edge, and T is the capture period corresponding to the third transition edge waveform. The current rotor position count value corresponding to the switched reluctance motor is compared with the preset control parameters, and phase output control is performed according to the comparison result. The preset control parameters may include, but are not limited to, the position count range corresponding to the preset turn-on angle and the position count range corresponding to the preset turn-off angle. How the controller performs phase output control on the switched reluctance motor according to the comparison result of the current rotor position count value corresponding to the switched reluctance motor and the preset control parameters can be referred to the existing related technologies, and will not be described in detail in this embodiment.

[0119] Furthermore, in this embodiment, in addition to multiple first Hall sensors, the sensor board also has at least one third Hall sensor. The multiple first Hall sensors detect the rotation of the first magnetic ring to obtain a first rotor position detection signal, and send this signal to the controller via an output interface. The at least one third Hall sensor detects the rotation of the second magnetic ring to obtain a third rotor position detection signal, and sends this signal to the controller via an output interface. The controller can then receive the first rotor position detection signals from the multiple first Hall sensors and the third rotor position detection signal from the at least one third Hall sensor. In any first rotor position detection signal, one electrical angle period is 360°, and the electrical angle period is specifically divided into A position count values. After receiving the first rotor position detection signals from the multiple first Hall sensors and the third rotor position detection signal from the at least one third Hall sensor, the controller can generate a first transition edge waveform based on the multiple first rotor position detection signals, and a fourth transition edge waveform based on the at least one third rotor position detection signal. Specifically, the controller can generate the first transition edge waveform by performing logical operations on the multiple first rotor position detection signals, and generate the fourth transition edge waveform based on the at least one third Hall sensor. The third rotor position detection signal is used for logical operations to generate the fourth transition edge waveform, but is not limited to this. After generating the fourth transition edge waveform, the controller can determine the position count values ​​corresponding to each rising edge and each falling edge in the fourth transition edge waveform based on the position count values ​​corresponding to each rising edge and each falling edge in the first transition edge waveform. After determining the position count values ​​corresponding to each rising edge and each falling edge in the fourth transition edge waveform, the controller can determine the fourth transition edge waveform based on the position count values ​​corresponding to the third rising edge and the third falling edge. The edge spacing value corresponding to the waveform diagram is determined as follows: when the position count value corresponding to the third rising edge is greater than the position count value corresponding to the third falling edge, the difference between the position count value corresponding to the third rising edge and the position count value corresponding to the third falling edge is determined as the edge spacing value corresponding to the waveform diagram of the fourth transition edge. When the position count value corresponding to the third rising edge is less than the position count value corresponding to the third falling edge, the difference between the position count value corresponding to the third falling edge and the position count value corresponding to the third rising edge is determined as the edge spacing value corresponding to the waveform diagram of the fourth transition edge. Here, the third rising edge and the third falling edge are any adjacent rising edge and falling edge in the waveform diagram of the fourth transition edge.After determining the edge spacing value corresponding to the fourth transition edge waveform, the controller can obtain the capture time corresponding to the third rising edge and the third falling edge through the first timer. Based on these capture times, the controller determines the capture period corresponding to the fourth transition edge waveform. Specifically, when the capture time corresponding to the third rising edge is greater than the capture time corresponding to the third falling edge, the difference between these two times is determined as the capture period corresponding to the fourth transition edge waveform. Conversely, when the capture time corresponding to the third rising edge is less than the capture time corresponding to the third falling edge, the difference between the two times is used as the capture period. The difference between the capture time of the first rising edge and the capture time corresponding to the third rising edge is determined as the capture period corresponding to the fourth rising edge waveform. Finally, the controller can calculate the speed of the switched reluctance motor based on the edge spacing value, the capture period, and the preset speed calculation constant of the fourth rising edge waveform. That is, the edge spacing value, the capture period, and the preset speed calculation constant of the fourth rising edge waveform are substituted into the first preset formula to calculate the speed of the switched reluctance motor. The preset speed calculation constant is determined based on the number of motor phases N, the number of rotor poles M, and the position count value A of the switched reluctance motor. The first preset formula is as follows:

[0120] v = m * Kv / T

[0121] Where v is the rotational speed of the switched reluctance motor, m is the edge spacing value corresponding to the fourth transition edge waveform, Kv is the preset rotational speed calculation constant, and T is the capture period corresponding to the fourth transition edge waveform.

[0122] Furthermore, in this embodiment, after calculating the rotational speed of the switched reluctance motor based on the fourth transition edge waveform, the controller can also control the phase output of the switched reluctance motor based on the fourth transition edge waveform: based on a preset time interval, that is, every time the preset time interval passes, the second timer obtains the capture time and the current time corresponding to the third target edge, wherein the third target edge is the rising edge or falling edge in the fourth transition edge waveform where the capture time is less than the current time and the capture time is closest to the current time. The preset time interval can be, but is not limited to, 1ms, 3ms, 5ms, etc.; and obtains the motor rotation direction. Based on the position count value corresponding to the third target edge, the edge spacing value corresponding to the fourth transition edge waveform, the capture time corresponding to the third target edge, the current time, the capture period corresponding to the fourth transition edge waveform, and the motor rotation direction, the current rotor position count value is calculated. Specifically, when the motor rotation direction is positive, the position count value corresponding to the third target edge, the edge spacing value corresponding to the fourth transition edge waveform, the capture time corresponding to the third target edge, the current time, and the capture period corresponding to the fourth transition edge waveform are substituted into the second preset formula to calculate the current rotor position count value corresponding to the switched reluctance motor. The second preset formula is as follows:

[0123] Ai = An + m * (t1 - t2) / T

[0124] Where Ai is the current rotor position count value corresponding to the switched reluctance motor, An is the position count value corresponding to the third target edge, m is the edge spacing value corresponding to the fourth transition edge waveform, t1 is the current time, t2 is the capture time corresponding to the third target edge, and T is the capture period corresponding to the fourth transition edge waveform.

[0125] When the motor rotates in the opposite direction, the position count value corresponding to the third target edge, the edge spacing value corresponding to the fourth transition edge waveform, the capture time corresponding to the third target edge, the current time, and the capture period corresponding to the fourth transition edge waveform are substituted into the third preset formula to calculate the current rotor position count value corresponding to the switched reluctance motor. The third preset formula is as follows:

[0126] Ai = An - m * (t1 - t2) / T

[0127] Where Ai is the current rotor position count value corresponding to the switched reluctance motor, An is the position count value corresponding to the third target edge, m is the edge spacing value corresponding to the fourth transition edge waveform, t1 is the current time, t2 is the capture time corresponding to the third target edge, and T is the capture period corresponding to the fourth transition edge waveform. The current rotor position count value corresponding to the switched reluctance motor is compared with the preset control parameters, and phase output control is performed according to the comparison result. The preset control parameters may include, but are not limited to, the position count range corresponding to the preset turn-on angle and the position count range corresponding to the preset turn-off angle. How the controller performs phase output control on the switched reluctance motor according to the comparison result of the current rotor position count value corresponding to the switched reluctance motor and the preset control parameters can be referred to the existing related technologies, and will not be elaborated on in this embodiment.

[0128] This application provides a switched reluctance motor system and a speed detection method. Compared with the prior art, which uses multiple photoelectric switch position sensors to detect the rotation of a photoelectric sensor code disk to obtain the rotor position detection signal of the switched reluctance motor, this application provides a first magnetic ring on the motor shaft of the switched reluctance motor. Multiple first Hall sensors mounted on a sensor plate detect the rotation of the first magnetic ring to obtain a first rotor position detection signal. The multiple first Hall sensors send the obtained first rotor position detection signal to a controller through an output interface. The controller then calculates the speed of the switched reluctance motor based on the multiple first rotor position detection signals and controls the phase output of the switched reluctance motor based on the multiple first rotor position detection signals. Because the manufacturing process of the magnetic ring is relatively simple, the processing precision of the first magnetic ring can be ensured to be high, thereby ensuring the high precision of the first rotor position detection signal obtained by the first Hall sensors. This improves the accuracy of calculating the switched reluctance motor speed and the accuracy of phase output control of the switched reluctance motor.

[0129] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0130] It is understood that the relevant features in the above systems and methods can be referenced interchangeably. Furthermore, the terms "first," "second," etc., in the above embodiments are used to distinguish between embodiments and do not represent the superiority or inferiority of any particular embodiment.

[0131] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the system described above can be referred to the corresponding process in the above method embodiments, and will not be repeated here.

[0132] The algorithms and displays provided herein are not inherently related to any particular computer, virtual system, or other device. Various general-purpose systems can also be used in conjunction with the teachings herein. The required structure for constructing such systems is apparent from the above description. Furthermore, this application is not directed to any particular programming language. It should be understood that the content of this application described herein can be implemented using various programming languages, and the above description of specific languages ​​is for the purpose of disclosing the best mode of implementation of this application.

[0133] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0134] Similarly, it should be understood that, in order to simplify this disclosure and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of this application, various features of this application are sometimes grouped together in a single embodiment, figure, or description thereof. However, this approach to disclosure should not be construed as reflecting an intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected in the following claims, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0135] Those skilled in the art will understand that modules in the device of the embodiments can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiments can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination can be used to combine all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device so disclosed. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0136] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0137] The various component embodiments of this application can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some or all of the components in the switched reluctance motor system and speed detection method according to the embodiments of this application. This application can also be implemented as a device or apparatus program (e.g., a computer program and computer program product) for performing part or all of the methods described herein. Such an implementation of this application can be stored on a computer-readable medium, or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0138] It should be noted that the above embodiments are illustrative of this application and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. This application can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

Claims

1. A switched reluctance motor system, characterized in that, include: An N-phase switched reluctance motor, wherein the rotor of the switched reluctance motor is an M-pole rotor, and N and M are positive integers greater than 1; Controller; The first magnetic ring is fixed around the outside of the first magnetic ring support member. The first magnetic ring support member is connected to the motor shaft of the switched reluctance motor. The first magnetic ring rotates coaxially with the rotor in the switched reluctance motor. The first magnetic ring includes M N poles and M S poles, and the M N poles and M S poles alternate with each other. The first magnetic ring is a radially magnetized magnetic ring. N first Hall sensors obtain the first rotor position detection signal by detecting the rotation of the first magnetic ring; The second magnetic ring is fixed around the outside of the second magnetic ring support member. The second magnetic ring support member is connected to the motor shaft of the switched reluctance motor. The second magnetic ring rotates coaxially with the rotor in the switched reluctance motor. The second magnetic ring contains X N poles and X S poles, with the X N poles and X S poles alternating. The second magnetic ring is a radially magnetized magnetic ring, and X is an integer multiple of M. Y third Hall sensors obtain the third rotor position detection signal by detecting the rotation of the second magnetic ring, where Y is a positive integer greater than or equal to 1; The controller is configured to generate a first transition edge waveform based on a plurality of the first rotor position detection signals; A fourth transition edge waveform is generated based on at least one of the third rotor position detection signals; Based on the position count value corresponding to each rising edge and each falling edge in the first transition edge waveform diagram, determine the position count value corresponding to each rising edge and each falling edge in the fourth transition edge waveform diagram. Based on the position count value corresponding to the third rising edge and the position count value corresponding to the third falling edge, the edge spacing value corresponding to the fourth transition edge waveform is determined, wherein the third rising edge and the third falling edge are any adjacent rising edge and falling edge in the fourth transition edge waveform. The first timer is used to obtain the capture time corresponding to the third rising edge and the capture time corresponding to the third falling edge. The capture period corresponding to the fourth edge waveform is determined based on the capture time corresponding to the third rising edge and the capture time corresponding to the third falling edge. The rotational speed of the switched reluctance motor is calculated based on the edge spacing value, the capture period, and the preset rotational speed calculation constant.

2. The system according to claim 1, characterized in that, The switched reluctance motor system also includes: A sensor board is provided with an output interface, N first Hall sensors and a first signal processing circuit. The first Hall sensors are connected to the output interface through the first signal processing circuit. The output interface is connected to the controller. The sensor board is fixed to the motor end cover of the switched reluctance motor. The sensor board is also provided with N second Hall sensors and a second signal processing circuit. The second Hall sensors are connected to the output interface through the second signal processing circuit. The sensor board is also provided with Y third Hall sensors and a third signal processing circuit. The third Hall sensors are connected to the output interface through the third signal processing circuit. The second Hall sensor detects the rotation of the first magnetic ring to obtain a second rotor position detection signal, and sends the second rotor position detection signal to the controller through the output interface. The controller then calculates the rotational speed of the switched reluctance motor based on the multiple first rotor position detection signals and the multiple second rotor position detection signals, and controls the phase output of the switched reluctance motor based on the multiple first rotor position detection signals and the multiple second rotor position detection signals.

3. The system according to claim 2, characterized in that, The sensor plate is arc-shaped and surrounds the outside of the first magnetic ring, with the center of the sensor plate at the same position as the center of the first magnetic ring. N first Hall sensors are spaced apart on the sensor plate along the arc length direction of the sensor plate. The central angle corresponding to the arc length of the distance between two adjacent first Hall sensors on the sensor plate is K1*(360° / M)+360° / (M*N), where K1 is an integer greater than or equal to 0 and less than M. N second Hall sensors are spaced apart on the sensor plate along the arc length direction of the sensor plate. The central angle corresponding to the arc length of the distance between two adjacent second Hall sensors on the sensor plate is K1*(360° / M)+360° / (M*N), where K1 is an integer greater than or equal to 0 and less than M. The central angle corresponding to the arc length of the distance between each of the first Hall sensor and its corresponding second Hall sensor on the sensor plate is K2*(360° / M)+360° / (4*M), where K2 is an integer greater than or equal to 0 and less than M.

4. The system according to claim 2, characterized in that, A magnetic shielding plate is provided between the first magnetic ring and the second magnetic ring; The sensor plate is arc-shaped and surrounds the outside of the first magnetic ring and the second magnetic ring. The center of the sensor plate is at the same position as the center of the first magnetic ring and the center of the second magnetic ring. N first Hall sensors are spaced apart on the sensor plate along the arc length direction of the sensor plate. The central angle corresponding to the arc length of the distance between two adjacent first Hall sensors on the sensor plate is K1*(360° / M)+360° / (M*N), where K1 is an integer greater than or equal to 0 and less than M. Y of the third Hall sensors are spaced apart on the sensor plate along the arc length direction of the sensor plate. The central angle corresponding to the arc length of the distance between two adjacent third Hall sensors on the sensor plate is K3*(360° / X)+360° / (Y*X), where K3 is an integer greater than or equal to 0 and less than X. N of the first Hall sensors and Y of the third Hall sensors are arranged side by side in the width direction of the sensor plate.

5. A method for detecting rotational speed, characterized in that, The method is applied to a switched reluctance motor system as described in any one of claims 1-4, and the method includes: Receives first rotor position detection signals sent by multiple first Hall sensors; A first transition edge waveform is generated based on multiple first rotor position detection signals; Calculate the speed of the switched reluctance motor based on the waveform diagram of the first transition edge. One electrical angle period in the first rotor position detection signal is 360°, and the electrical angle period is specifically divided into A position count values; after generating the first transition edge waveform based on multiple first rotor position detection signals, the method further includes: Receive a third rotor position detection signal sent by at least one third Hall sensor; A fourth transition edge waveform is generated based on at least one of the third rotor position detection signals; The step of calculating the speed corresponding to the switched reluctance motor based on the waveform diagram of the first transition edge includes: Based on the position count value corresponding to each rising edge and each falling edge in the first transition edge waveform diagram, determine the position count value corresponding to each rising edge and each falling edge in the fourth transition edge waveform diagram. Based on the position count value corresponding to the third rising edge and the position count value corresponding to the third falling edge, the edge spacing value corresponding to the fourth transition edge waveform is determined, wherein the third rising edge and the third falling edge are any adjacent rising edge and falling edge in the fourth transition edge waveform. The first timer is used to obtain the capture time corresponding to the third rising edge and the capture time corresponding to the third falling edge. The capture period corresponding to the fourth edge waveform is determined based on the capture time corresponding to the third rising edge and the capture time corresponding to the third falling edge. The rotational speed of the switched reluctance motor is calculated based on the edge spacing value, the capture period, and the preset rotational speed calculation constant.

6. The method according to claim 5, characterized in that, One electrical angle period in the first rotor position detection signal is 360°, and the electrical angle period is specifically divided into A position count values; the calculation of the rotational speed corresponding to the switched reluctance motor based on the first transition edge waveform includes: Based on the position count value corresponding to the first rising edge and the position count value corresponding to the first falling edge, the edge spacing value corresponding to the first transition edge waveform is determined, wherein the first rising edge and the first falling edge are any adjacent rising edge and falling edge in the first transition edge waveform. The first timer is used to obtain the capture time corresponding to the first rising edge and the capture time corresponding to the first falling edge. The capture period corresponding to the first edge transition waveform is determined based on the capture time corresponding to the first rising edge and the capture time corresponding to the first falling edge. The rotational speed of the switched reluctance motor is calculated based on the edge spacing value, the capture period, and the preset rotational speed calculation constant.

7. The method according to claim 5, characterized in that, One electrical angle period in the first rotor position detection signal is 360°, and the electrical angle period is specifically divided into A position count values; after generating the first transition edge waveform based on multiple first rotor position detection signals, the method further includes: The system receives second rotor position detection signals sent by multiple second Hall sensors, wherein one electrical angle period of the second rotor position detection signal is 360°, and the electrical angle period is specifically divided into A position count values; A second transition edge waveform is generated based on multiple second rotor position detection signals; A third transition edge waveform is generated based on the first transition edge waveform and the second transition edge waveform. The step of calculating the speed corresponding to the switched reluctance motor based on the waveform diagram of the first transition edge includes: Based on the position count value corresponding to the second rising edge and the position count value corresponding to the second falling edge, the edge spacing value corresponding to the third transition edge waveform is determined, wherein the second rising edge and the second falling edge are any adjacent rising edge and falling edge in the third transition edge waveform. The capture time corresponding to the second rising edge and the capture time corresponding to the second falling edge are obtained by the first timer; The capture period corresponding to the third edge waveform is determined based on the capture time corresponding to the second rising edge and the capture time corresponding to the second falling edge. The rotational speed of the switched reluctance motor is calculated based on the edge spacing value, the capture period, and the preset rotational speed calculation constant.

8. The method according to claim 6, characterized in that, The method further includes: Based on a preset time interval, the capture time and the current time corresponding to the first target edge are obtained by the second timer, wherein the first target edge is the rising edge or falling edge in the waveform diagram of the first transition edge that is closest to the current time. Obtain the motor rotation direction; The current rotor position count value is calculated based on the position count value corresponding to the first target edge, the edge spacing value corresponding to the first transition edge waveform, the capture time corresponding to the first target edge, the current time, the capture period corresponding to the first transition edge waveform, and the motor rotation direction. The current rotor position count value is compared with the preset control parameters, and phase output control is performed based on the comparison result.

9. The method according to claim 7, characterized in that, The method further includes: Based on a preset time interval, the capture time and the current time corresponding to the second target edge are obtained through the second timer, wherein the second target edge is the rising edge or falling edge in the waveform diagram of the third transition edge that is closest to the capture time and the current time. Obtain the motor rotation direction; The current rotor position count value is calculated based on the position count value corresponding to the second target edge, the edge spacing value corresponding to the third transition edge waveform, the capture time corresponding to the second target edge, the current time, the capture period corresponding to the third transition edge waveform, and the motor rotation direction. The current rotor position count value is compared with the preset control parameters, and phase output control is performed based on the comparison result.

10. The method according to claim 5, characterized in that, The method further includes: Based on a preset time interval, the capture time and the current time corresponding to the third target edge are obtained through the second timer. The third target edge is the rising edge or falling edge in the waveform diagram of the fourth transition edge that is closest to the capture time and the current time. Obtain the motor rotation direction; The current rotor position count value is calculated based on the position count value corresponding to the third target edge, the edge spacing value corresponding to the fourth transition edge waveform, the capture time corresponding to the third target edge, the current time, the capture period corresponding to the fourth transition edge waveform, and the motor rotation direction. The current rotor position count value is compared with the preset control parameters, and phase output control is performed based on the comparison result.

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