Angle detection implementation method, device and equipment based on eddy current motor

Abstract

The invention provides an eddy current motor-based angle detection implementation method, device and equipment, and the method comprises the following steps: obtaining a periodic signal of an eddy current sensor, and generating a pulse frequency signal in direct proportion to the rotating speed according to the periodic signal; acquiring the number of pulses in unit time according to the pulse frequency signal, and determining the rotating speed of the motor based on the number of pulses in unit time; obtaining the rotating speed of the motor based on measuring the pulse number in unit time; two magnetic fields generated by the motor rotor and the eddy current position sensor interact with each other to generate a voltage signal; acquiring a position parameter, obtaining a voltage signal based on the sinusoidal signal and the cosine signal, and determining the position of a motor rotor; therefore, according to the eddy current-based motor angle detection implementation method provided by the scheme, the rotating speed and the position of the motor can be accurately measured by detecting the change of the eddy current, the precision is high, and the power consumption is low; and a digital communication interface is adopted, so that the adaptive capability is relatively high.

Description

Technical Field

[0001] The present disclosure belongs to the technical field of motor angle detection, and particularly relates to a method, device and equipment for realizing motor angle detection based on eddy current. Background Art

[0002] As the main power source in the industrial field, motors are widely used in various industries. Accurately collecting the position and speed state of the motor rotor is the basis for controlling the motor. With the rapid development of modern communication technology and control technology, traditional measurement methods can no longer meet the application requirements of various industries. Currently, for motor angle and speed detection, a scheme based on a resolver or an optical encoder is generally adopted. The resolver is used to detect the motor angle position and speed. The resolver is an electromagnetic sensor, which is a small AC motor for measuring angles and is used to measure the angular displacement and angular velocity of the rotating shaft of a rotating object. It consists of a stator and a rotor. The resolver can be used to transmit the rotation angle or electrical signal in a synchronous servo system and a digital servo system.

[0003] However, although the resolver can detect the motor angle and speed, it has the following disadvantages: 1. The amplitude of the sine / cosine modulation signal for ECU demodulation is weak and cannot be compatible with the next-generation digital interface; 2. The digital signal output by the optical encoder is usually a TTL level, that is, a square wave signal with a fixed duty cycle, which is greatly affected by external factors such as the intensity of light, and has low accuracy and high cost at the same time; 3. For some industrial application scenarios, such as when a steel mill frequency converter drives a DC speed control motor, the load inertia is large, the starting impact is large, and the measurement power consumption is large. Summary of the Invention

[0004] In view of the above problems, the present disclosure proposes a method, device and equipment for realizing motor angle detection based on eddy current, which can accurately measure the speed and position of the motor by detecting the change of eddy current, with high accuracy and low power consumption; and it is a digital communication interface with strong adaptability.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for realizing motor angle detection based on eddy current includes:

[0007] Obtain the periodic signal of the eddy current sensor, and generate a pulse frequency signal proportional to the speed according to the periodic signal;

[0008] Obtain the number of pulses per unit time according to the pulse frequency signal, and determine the motor speed parameter based on the number of pulses per unit time;

[0009] Based on measuring the number of pulses per unit time, calculate the motor speed parameter α;

[0010] Obtain the voltage signal generated by the interaction of the magnetic fields of the motor rotor and the eddy current position sensor;

[0011] Based on the sine signal and cosine signal in the periodic signal, calculate the maximum value, minimum value and average value of the voltage signal, and calculate the position parameter θfb through the arctangent function to determine the position of the motor rotor.

[0012] Optionally, obtain the periodic signal output by the eddy current sensor, including:

[0013] Obtain the original signal. After the eddy current sensor generates the first alternating magnetic field, due to the rotation of the motor rotating component, eddy currents are generated in its metal conductor in the first alternating magnetic field. The eddy currents generate a second alternating magnetic field, and the second alternating magnetic field interacts with the first alternating magnetic field to generate the original signal;

[0014] Obtain the periodic signal. The distance between the motor rotating component and the eddy current sensor changes regularly, so the original signal is output as a periodic signal by the sensor.

[0015] Optionally, measure the pulse frequency signal per unit time, and calculate the motor speed parameter α according to the number of pulses per unit time in the pulse frequency signal.

[0016] Optionally, the eddy current position sensor includes a transmitting coil and a receiving coil;

[0017] The transmitting coil can generate an excitation magnetic field after the eddy current position sensor is powered on;

[0018] The excitation magnetic field acts on the new magnetic field of the eddy current generated by the rotation of the motor rotor, the induced voltage in the receiving coil changes, and is demodulated and processed by the signal processing unit.

[0019] Based on the number of pulses measured per unit time, calculate the motor speed parameter α, including:

[0020] Optionally, the voltage signal parameters p, parameter n, and parameters p1, parameter n1, including:

[0021] The calculated value of the sine signal sin needs to obtain the maximum value, minimum value and average value obtained by subtracting between parameter p and parameter n;

[0022] The calculated value of the cosine signal cos needs to obtain the maximum value, minimum value and average value obtained by subtracting between parameter p1 and parameter n1.

[0023] Optionally, the signal output by the eddy current position sensor is a four-channel differential signal.

[0024] Optionally, the position parameter θfb is calculated by using the calculated value of the sine function sin and the calculated value of the cosine signal cos in the arctangent function formula to obtain the position θfb feedback by the eddy current position sensor, thereby determining the position of the motor rotor.

[0025] An eddy current-based motor angle detection device, comprising:

[0026] A primary signal transmission and reception unit; composed of an integrated coil, a filter circuit, an internal crystal oscillator of the chip, and a demodulation circuit;

[0027] A secondary signal processing unit; processes the front-end signal through the internal chip of the device and outputs it to the decoding unit;

[0028] A tertiary ECU communication unit; the central processing unit processes the signal transmitted by the secondary signal processing unit, decodes and inversely calculates the position and speed of the motor rotor.

[0029] An electronic device, comprising: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory complete communication with each other through the communication bus;

[0030] A memory, storing a computer program;

[0031] When the processor executes the program stored in the memory, it implements the method for detecting the angle of an eddy current-based motor.

[0032] A computer-readable storage medium, storing a computer program, which when executed by a processor, implements the method for detecting the angle of an eddy current-based motor.

[0033] One or at least one of the above technical solutions in the embodiments of the present disclosure has at least the following technical effects: Compared with the prior art, the present invention provides a method for detecting the angle of an eddy current-based motor. First, a periodic signal output by an eddy current sensor is obtained, and a pulse frequency signal proportional to the speed is obtained from the periodic signal; then, based on measuring the number of pulses within a unit time, the motor speed is calculated; and through the interaction of two magnetic fields generated by the motor rotor and the eddy current position sensor, the eddy current position sensor generates a voltage signal; since the maximum value, minimum value, and average value of the voltage signal are calculated according to the sine signal and the cosine signal, and then the position parameter is calculated through the arctangent function, thereby determining the position of the motor rotor; it can be seen that the detection implementation method provided by this solution can accurately measure the speed and position of the motor by detecting the change of eddy current, with high accuracy and low power consumption; and it is a digital communication interface with strong adaptability.

[0034] Other features and advantages of the present disclosure will be set forth in the following description, and in part will be obvious from the description, or may be learned by practice of the present disclosure. The objectives and other advantages of the present disclosure may be realized and attained by the structure particularly pointed out in the specification and the drawings. Description of the Drawings

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the following briefly introduces the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0036] Figure 1 It is a schematic flowchart of a method for realizing angle detection based on an eddy current motor according to the present disclosure;

[0037] Figure 2 It is a schematic diagram of an electronic device according to the present disclosure;

[0038] Figure 3 It is a flowchart of the system architecture according to the present disclosure. Detailed Embodiments

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure clearer, the following clearly and completely describes the technical solutions in the embodiments of the present disclosure with reference to the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are some, but not all, of the embodiments of the present disclosure. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present disclosure without creative efforts fall within the scope of protection of the present disclosure.

[0040] It should be noted that the terms "first", "second", etc. in this application are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so as to describe the embodiments of the present application here. In this application, the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal", etc. is based on the orientation or positional relationship shown in the drawings.

[0041] As described in the background art, currently, the measurement of the motor angle position and speed is generally based on a resolver. A resolver is an electromagnetic sensor, also known as a synchro resolver; it is a relatively small AC motor capable of measuring angles, consisting of a stator and a rotor, and can be used to measure the shaft angular displacement and angular velocity of a rotating object; the rotor winding serves as the secondary side of the transformer, and an induced voltage is obtained through electromagnetic coupling. The working principle of the resolver is basically similar to that of an ordinary transformer. The difference is that the primary and secondary windings of an ordinary transformer are relatively fixed, so the ratio of the output voltage to the input voltage is a constant. However, the primary and secondary windings of the resolver change their relative positions with the angular displacement of the rotor. Therefore, the magnitude of its output voltage changes with the rotor angular displacement. The voltage amplitude of the output winding has a sine or cosine function relationship with the rotor rotation angle, or maintains a certain proportional relationship, or is linear with the rotation angle within a certain rotation angle range; and the resolver can be used to transmit the rotation angle or electrical signal in a synchronous servo system and a digital servo system; but there are still some problems to be solved in measuring through the resolver:

[0042] One is that the power consumption of the power supply is relatively large. For example, when the resolver is applied to a variable-frequency drive motor in a factory to measure the shaft angular displacement and angular velocity, the load inertia is relatively large, and the driving impact force is large, resulting in a large power consumption of the measurement power supply;

[0043] The second is that a sine / cosine modulation signal needs to be obtained, but the amplitude of the demodulation signal of the resolver ECU is weak and cannot be compatible with the next-generation digital interface;

[0044] The third is that the output voltage amplitude of the inverter is relatively low, so it is relatively sensitive. Since the excitation frequency is close to it and the output voltage amplitude is low, it is easily interfered;

[0045] The fourth is that the digital signal output by the optical encoder is usually a TTL level, that is, a square wave signal with a fixed duty cycle, which is greatly affected by external factors such as the intensity of light, and has low accuracy and high cost at the same time;

[0046] Therefore, to solve the above problems, the present invention proposes a method for realizing motor angle detection based on eddy current, using a motor eddy current position sensor. Based on the eddy current effect, by detecting this eddy current, the speed and position of the motor can be accurately measured, with high accuracy and low power consumption; and it is a digital communication interface with strong adaptability.

[0047] (Embodiment 1)

[0048] To address the above problems, this embodiment provides a method for realizing motor angle detection based on eddy current, see Figure 1 , including:

[0049] S100: Acquire a periodic signal of the eddy current sensor, and generate a pulse frequency signal proportional to the rotation speed according to the periodic signal;

[0050] S200: Obtaining the number of pulses per unit time according to the pulse frequency signal, and determining the motor speed parameter based on the number of pulses per unit time;

[0051] S300: Calculate the motor speed parameter α based on the number of pulses per unit time;

[0052] S400: obtaining a voltage signal generated by the interaction between the two magnetic fields of the motor rotor and the eddy current position sensor;

[0053] S500: Calculate the maximum value, minimum value and average value of the voltage signal based on the sine signal and the cosine signal in the periodic signal, calculate the position parameter θfb through the inverse tangent function, and determine the motor rotor position.

[0054] It should be noted that the eddy current sensor is a contactless sensor that works based on the principle of electromagnetic induction. Based on the eddy current effect, when the magnetic flux passing through the conductor loop changes, an induced current will be generated inside the conductor loop. This current is the eddy current. Therefore, during the operation of the motor to be measured, the coil of the eddy current sensor is close to the rotating iron core or metal parts, and the magnetic field of the sensor coil will change with the position of the rotor, thereby causing changes in the eddy current. By detecting this change in the eddy current, the speed and position of the motor can be accurately measured.

[0055] Among them, the generation of eddy current is based on Faraday's law of electromagnetic induction and Lenz's law; when a bulk metal conductor is in a changing magnetic field or when the conductor cuts the magnetic lines of force in the magnetic field, the magnetic flux inside the conductor will change. According to Faraday's law of electromagnetic induction, when the magnetic flux in a closed loop changes, an induced electromotive force will be generated in the loop. For a bulk metal conductor, it can be equivalent to a circle of closed circuits in the circumferential direction. When the magnetic flux changes, an induced electromotive force will be generated in these equivalent closed circuits.

[0056] Moreover, since the bulk metal conductor is a whole, there are a large number of freely moving electrons in it. When an induced electromotive force is generated, these free electrons move in a directed manner under the action of the electromotive force, thereby forming an induced current in the metal conductor. Since the flow path of this induced current is a closed vortex inside the conductor, just like a whirlpool in water, it is called eddy current.

[0057] Among them, S100 is to obtain the periodic signal output by the eddy current sensor. The eddy current sensor is installed beside the motor to be measured, and close to the rotating shaft of the motor or beside the rotating component with teeth or grooves. The probe of the sensor should maintain a certain distance from the metal surface to be measured to facilitate the generation of the subsequent electromagnetic field and the reception of the subsequent signal. When the rotating shaft or rotating component of the motor rotates, the metal conductor on its surface generates eddy currents in the alternating magnetic field. The eddy currents will generate a new alternating magnetic field, which interacts with the original magnetic field, causing changes in the inductance, impedance, and quality factor of the sensor coil, etc., so as to receive the original signal. And because there are teeth and grooves on the rotating component, the teeth and grooves are gear-shaped with equally spaced protrusions and depressions. Therefore, when the rotating component rotates, the distance between the eddy current sensor and the rotating component changes continuously, so that the original signal output by the eddy current sensor is a periodic signal.

[0058] S200: The periodic signal obtained from S100 is processed by the signal processing unit. After the periodic signal is amplified and rectified, the obtained signal after removing the stray current is a pulse frequency signal proportional to the rotational speed of the rotating component of the motor. Therefore, by measuring the number of pulse frequency signals per unit time, the rotational speed parameter α of the motor can be measured.

[0059] S300: To determine the position of the motor by measuring the eddy current, it is obtained by measuring the voltage signal caused by the change in the induced voltage due to the magnetic field effect. The eddy current position sensor mainly consists of two parts: a transmitting coil and a receiving coil. When the eddy current position sensor is powered on, the transmitting coil in it generates an excitation magnetic field. Since the metal component on the rotor of the motor to be measured rotates in the magnetic field, it will cut the magnetic induction line to generate eddy currents. These eddy currents will generate a new magnetic field, and the new magnetic field interacts with the original excitation magnetic field, thus causing a change in the induced voltage in the receiving coil. The voltage signal is collected, and the voltage signal is demodulated and processed by the signal processing unit. The signal processing module of the eddy current position sensor demodulates and processes the voltage signal of the receiving coil to obtain the voltage signal corresponding to the position of the motor.

[0060] Among them, S400: the signal parameters p, n, p1, and n1 output by the eddy current position sensor, and the output voltage signal is generally four-channel differential signals, namely sinp, sinn, cosp, and cosn. These voltage signals are calculated and processed by calculating the maximum value, minimum value, and average value of the sine signal sin x = sinp - sinn and calculating the maximum value, minimum value, and average value of the cosine signal cos x = cosp - cosn; finally, the several values of the sine signal sin x and the several values of the cosine signal cos x obtained by calculation are substituted through the arctangent function θ = arctan(sin x / cos x) to obtain the position θfb feedback by the eddy current position sensor, so as to determine the position of the motor rotor.

[0061] In one preferred embodiment, it further includes: S401: calculating the effective magnetic flux densities Bmax, Bmin, and B0 based on the maximum value vmax, minimum value vmin, and average value v0 of the obtained voltage; based on the area S of the eddy current position sensor and the obtained effective magnetic flux densities Bmax, Bmin, and B0.

[0062] In one preferred embodiment, S402 specifically includes: obtaining the phase relationships θmax, θmin, and θ0; obtaining the phase average value θ; obtaining the relative position θ between the eddy current position sensor and the motor rotor; calculating the position parameter θ based on the phase relationships θmax, θmin, and θ0 and the phase average value θ.

[0063] In one preferred embodiment, S403 specifically includes: taking the derivative of Sin(x) and Cos(x), and getting y = Sin(x) + Dsin(x + π / 2) = 2D * Sin(x / 2) * COS(2x + π / 2); where D is a fixed value, A is an indefinite value, x is the independent variable, and y is the dependent variable; let 2D * Sin(x / 2) * COS(2x + π / 2) = 0; get Sin(x / 2) = 0 or COS(2x + π / 2) = 0; x = 2kπ (k ∈ Z); x = -π / 2 + (2k + 1)π / 2 (k ∈ Z).

[0064] In one preferred embodiment, S404 specifically includes: taking the average value of all the obtained valid Sin(x) data: taking the average value of all the obtained valid Cos(x) data, and kmax is the number of data.

[0065] A method for detecting the angle of an eddy current motor provided by the present invention can accurately measure the rotational speed and position of the motor rotor by detecting the change of eddy current, with high precision and low power consumption; and it is a digital communication interface with strong adaptability.

[0066] Among them, the eddy current position sensor includes an excitation coil, namely the transmitting coil, which is usually a magnetic path wound with a constant current source and can be used to generate a changing magnetic field, so as to interact with the new magnetic field generated by the eddy current of the measured element. The passive measuring element, such as a metal conductor or a metal probe, etc., in which the generated eddy current can change with the position of the target object.

[0067] It should be noted that since the rotor winding of the resolver rotates with the motor, the stator winding is fixed in position and the two stators are 90 degrees to each other. In this way, the winding forms a transformer with an angle-dependent coefficient, coupling the sinusoidal carrier wave applied to the rotor winding to the stator winding, and performing amplitude modulation related to the angle of the rotor winding on the output of the stator winding. Due to the installation position, the phase difference between the modulation output signals of the two stator windings is 90 degrees. By demodulating the two signals, the angular position information of the motor can be obtained. First, a pure sine wave and a cosine wave need to be received, and then they are divided to obtain the tangent value of the angle. Finally, the angle value is obtained through the arctangent function.

[0068] Furthermore, D1D2 in this solution is the stator excitation winding, and the excitation voltage applied to the stator excitation winding is a single-phase AC voltage, and the effective value of the AC voltage is set as Uf; assume that at the analyzed moment, the direction of the single-phase AC excitation voltage is positive at the top and negative at the bottom, that is, D1 is positive and D2 is negative. Therefore, an excitation current is generated in the stator excitation winding D1D2 at this time, and the direction of the excitation current is from top to bottom. Since the excitation voltage is a single-phase AC voltage, the excitation current is a single-phase AC current, or called a pulsating current; according to the electromagnetic induction theory, the single-phase AC current will generate a single-phase AC excitation magnetic field, or called a pulsating magnetic field; assume that the winding direction of the stator excitation winding D1D2 is clockwise spiral from top to bottom. According to the right-hand screw rule, through analysis, the direction of the pulsating magnetic field is vertically downward along the axis of the excitation winding; and the axis direction of the excitation winding or the direct-axis winding D1D2 is called the direct axis, that is, the d-axis. The magnitude of the direct-axis excitation magnetic field or the pulsating magnetic field is represented by the amplitude of the magnetic flux, marked as Φd, also called the amplitude of the direct-axis pulsating magnetic flux, and the direction of the direct-axis pulsating magnetic flux is consistent with the axis direction of the excitation winding; another set of stator windings is called the stator quadrature-axis winding D3D4. The axes of the two windings are 90° apart in space, and the axis direction of the quadrature-axis winding D3D4 is called the quadrature axis, that is, the q-axis.

[0069] Furthermore, according to the electromagnetic induction theory, a changing magnetic field will generate an induced electromotive force. Since the direct-axis pulsating magnetic field is a changing magnetic field, it will generate an induced electromotive force in all windings linked with it. Among the four windings of the resolver, the axis of the quadrature-axis winding D3D4 is perpendicular to the direct-axis pulsating magnetic field, and no magnetic force lines pass through the winding, so there is no induced electromotive force. However, in the direct-axis windings D1D2, the sine output windings Z1Z2, and the cosine output windings Z3Z4 of this solution, induced electromotive forces will be generated. The induced electromotive force Ef of the direct-axis winding D1D2 is balanced with the excitation voltage Uf, that is, Ef = Uf. The induced electromotive forces of the sine output windings Z1Z2 and the cosine output windings Z3Z4 directly output voltage outward in the open-circuit case. The effective values of the output voltages are Uz and Uy, which are respectively equal to the effective values Ez and Ey of the induced electromotive forces of the sine output windings Z1Z2 and the cosine output windings Z3Z4, that is, Uz = Ez, Uy = Ey.

[0070] (Embodiment 2)

[0071] Furthermore, in a preferred embodiment, it further includes a reverse rotation geographical indication setting module; the reverse rotation geographical indication setting module is used to set the reverse rotation geographical indication after determining the initial orientation of the motor; the reverse rotation geographical indication setting module includes a geographical indication register and a reset button; the geographical indication register is used to store the phase information of the eddy current position sensor; the observer judges whether the rotation direction of the motor has changed; if it has changed, press the reset button until it is observed that the phase of the reference mark has not changed.

[0072] (Embodiment 3)

[0073] This embodiment provides an eddy current motor angle detection device. Refer to Figure 3 , the measurement system architecture of this solution is divided into three levels:

[0074] The first-level signal transmission and reception unit; it consists of an integrated coil, a filter circuit, an internal crystal oscillator of the chip, and a demodulation circuit;

[0075] The second-level signal processing unit; the front-end signal is processed by the internal chip of the device and output to the decoding unit;

[0076] The third-level ECU communication unit; the signal transmitted by the second-level signal processing unit is processed and decoded by the central processing unit to calculate the position and speed of the motor rotor.

[0077] Among them, first, the target wheel in the signal transmission and reception unit receives the limited number, and the front-end sine signal is output to the secondary signal processing unit. The signal processing unit is inside the chip, powered by a power supply, and has an oscillator, a receiving coil, and an exciting coil. It demodulates the front-end signal and analog-outputs the rear-end signal to the decoding short circle, that is, the three-level ECU communication unit, which is powered by the ECU through a wire harness. The central processing unit processes and decodes the signal transmitted by the secondary signal processing unit to calculate the position and speed of the motor rotor.

[0078] Based on the same inventive concept, another aspect of the embodiments of the present disclosure further provides an electronic device 161, see Figure 2 , including a processor 164, a communication interface 165, a memory 162, and a communication bus. Among them, the processor 164, the communication interface 165, and the memory 162 communicate with each other through the communication bus;

[0079] The memory 162 stores a computer program 163;

[0080] When the processor 164 executes the program stored in the memory 162, it implements the method for realizing the detection of the angle of the eddy current motor.

[0081] The above communication bus may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The communication bus can be divided into an address bus, a data bus, a control bus, etc.

[0082] The communication interface 165 is used for communication between the electronic device 161 and other devices.

[0083] The memory 162 may include a Random Access Memory (RAM), and may also include a non-volatile memory, such as at least one disk memory. Optionally, the memory 162 may also be at least one storage device located far from the aforementioned processor 164.

[0084] The above-mentioned processor 164 may be a general-purpose processor 164, including a central processing unit 164 (CPU for short), a network processor 164 (NP for short), etc.; it may also be a digital signal processor 164 (DSP for short), an application specific integrated circuit (ASIC for short), a field-programmable gate array (FPGA for short), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0085] Based on the same inventive concept, another aspect of the embodiments of the present disclosure further provides a computer-readable storage medium storing a computer program 163, and when the computer program 163 is executed by the processor 164, an implementation method based on eddy current motor angle detection is realized.

[0086] The computer-readable storage medium may be included in the device / apparatus described in the above embodiments; it may also exist alone without being assembled into the device / apparatus. The above computer-readable storage medium carries one or more programs, and when the one or more programs are executed, an implementation method based on eddy current motor angle detection according to the embodiments of the present disclosure is realized.

[0087] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for realizing angle detection based on eddy current motor, characterized in that: include: Acquire the periodic signal of the eddy current sensor, and generate a pulse frequency signal proportional to the rotation speed according to the periodic signal; The number of pulses per unit time is obtained according to the pulse frequency signal, and the motor speed parameter is determined based on the number of pulses per unit time; Based on the number of pulses per unit time, the motor speed parameter α is calculated; Obtaining the voltage signal generated by the interaction between the two magnetic fields of the motor rotor and the eddy current position sensor; The maximum value, minimum value and average value of the voltage signal are calculated based on the sine signal and cosine signal in the periodic signal, and the position parameter θfb is calculated by the inverse tangent function to determine the motor rotor position.

2. The method according to claim 1, characterized in that Obtain the periodic signal of the eddy current sensor, including: Acquire the original signal. After the eddy current sensor generates the first alternating magnetic field, the rotating part of the motor rotates, and its metal conductor generates eddy currents in the first alternating magnetic field. A second alternating magnetic field is generated according to the eddy currents. The second alternating magnetic field interacts with the first alternating magnetic field to generate the original signal. When the eddy current sensor generates an alternating magnetic field, the eddy current signal generated by the metal conductor in the alternating magnetic field is obtained, and an induced alternating magnetic field is generated according to the eddy current signal.

3. The method according to claim 1 or 2, characterized in that: Generate a pulse frequency signal proportional to the rotation speed according to the periodic signal, including: The periodic signal is amplified and rectified to obtain a pulse frequency signal that is proportional to the speed of the motor's rotating parts.

4. The method according to claim 1, characterized in that: Based on the measurement of the number of pulses per unit time, the motor speed parameter α is calculated, including: The pulse frequency signal per unit time is measured, and the motor speed parameter α is calculated according to the number of pulses per unit time in the pulse frequency signal.

5. The method according to claim 1, characterized in that The transmitting coil generates an excitation magnetic field after the eddy current position sensor is powered on; The excitation magnetic field interacts with the new magnetic field of eddy currents generated by the rotation of the motor rotor, and the induced voltage changes in the receiving coil, which is demodulated and processed by the signal processing unit.

6. The method according to claim 1, characterized in that The voltage signal includes parameters p, n, p1 and n1, including: The calculated value of the sine signal sin requires obtaining the maximum value, minimum value, and average value obtained by subtracting the parameter p from the parameter n; The calculated value of the cosine signal cos requires obtaining the maximum value, minimum value and average value obtained by subtracting the parameter p1 from the parameter n1.

7. The method according to claim 1, characterized in that The signals output by the eddy current position sensor are four-way differential signals.

8. The method according to claim 1, characterized in that The position parameter θfb is calculated by the calculated value of the sine function sin and the calculated value of the cosine signal cos in the inverse tangent function formula to obtain the position θfb fed back by the eddy current position sensor, and the motor rotor position is determined.

9. An eddy current motor-based angle detection device, applied to any one of claims 1 to 8 in the eddy current motor-based angle detection implementation method, characterized in that: include: The first-level signal transmission and receiving unit is composed of an integrated coil, a filter circuit, a crystal oscillator inside the chip, and a demodulation circuit; Secondary signal processing unit; The front-end signal is processed by the internal chip of the device and output to the decoding unit; Level 3 ECU communication unit: The central processing unit processes and decodes the signals transmitted by the level 2 signal processing unit and inversely calculates the motor rotor position and motor speed.

10. An electronic device, characterized in that: include: A processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus; a memory storing a computer program; The processor, when executing the program stored in the memory, implements the method for realizing angle detection based on an eddy current motor according to any one of claims 1 to 8.

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