Fault detection method of eddy current sensor, related device, equipment and medium

Abstract

The invention discloses a fault detection method of an eddy current sensor, a related device, equipment and a medium, and the method comprises the steps: sampling a first AC signal and a second AC signal outputted by the eddy current sensor, and obtaining sampling data; based on the sampling data, determining whether the eddy current sensor has a target fault; wherein the target fault comprises at least one of a DC fault and an AC fault; under the condition that the eddy current sensor has a direct current fault, at least one of the first alternating current signal and the second alternating current signal is changed into a direct current signal from an alternating current signal; when the eddy current sensor has an alternating current fault, at least one of the first alternating current signal and the second alternating current signal becomes an abnormal alternating current signal. Through the mode, the fault type of the eddy current sensor can be detected, the fault reason and the fault position of the eddy current sensor can be quickly determined during maintenance, and the maintenance efficiency of the eddy current sensor is improved.

Description

Technical Field

[0001] The present application relates to the technical field of fault detection, and in particular to a fault detection method for an eddy current sensor and related devices, equipment and media. Background Art

[0002] Eddy current sensor (eddy current angle sensor) is an important measuring device widely used in industrial automation, aerospace, automobile and other fields. It is used to accurately measure the angle information (rotation angle) of the object being measured. The basic structure of eddy current sensor includes excitation coil, target wheel and signal processing circuit. The excitation coil generates an electromagnetic field under high-frequency current excitation. When the surface of the target wheel is close to the coil, eddy current will be generated. The size and distribution of eddy current will affect the magnetic field in the induction coil, thereby changing the induced current. By measuring this change, the angle information of the object being measured can be indirectly obtained.

[0003] However, the measurement accuracy of eddy current sensors is easily affected by environmental factors (such as temperature, humidity, electromagnetic interference, etc.). In an environment with large temperature changes, the performance of the electronic components of the eddy current sensor may drift, and changes in humidity may cause short circuits or corrosion in the circuits inside the eddy current sensor. Electromagnetic interference may distort the output signal of the sensor, resulting in inaccurate measurement results. In addition, during long-term use of eddy current sensors, the gap between the coil and the object being measured may change due to mechanical wear, fatigue, etc., thereby affecting the measurement accuracy. In addition, the signal processing circuit of the eddy current sensor may also fail, such as aging and damage of electronic components, causing the eddy current sensor to fail to work properly.

[0004] When the eddy current sensor fails, the signal output by the eddy current sensor becomes abnormal, which will affect the calculation of the angle information of the object being measured. Therefore, how to detect the fault of the eddy current sensor has become a technical problem that needs to be solved urgently. Summary of the invention

[0005] The main technical problem solved by the present application is to provide a fault detection method, device, equipment and computer-readable storage medium for an eddy current sensor, which can detect the fault type of the eddy current sensor.

[0006] To solve the above technical problems, a technical solution adopted in the present application is: to provide a fault detection method for an eddy current sensor, the method comprising: sampling a first AC signal and a second AC signal output by the eddy current sensor to obtain sampling data; based on the sampling data, determining whether the eddy current sensor has a target fault; wherein the target fault includes at least one of a DC fault and an AC fault; in the event that the eddy current sensor has a DC fault, at least one of the first AC signal and the second AC signal is changed from an AC signal to a DC signal; in the event that the eddy current sensor has an AC fault, at least one of the first AC signal and the second AC signal is changed to an abnormal AC signal.

[0007] Optionally, the sampling data includes first sampling values ​​of a first AC signal and second sampling values ​​of a second AC signal corresponding to several first sampling moments respectively; based on the sampling data, determining whether there is a target fault in the eddy current sensor includes: counting a first DC fault count corresponding to the first AC signal based on whether the first sampling value at each first sampling moment is within a first preset range, and counting a second DC fault count corresponding to the second AC signal based on whether the second sampling value at each first sampling moment is within the first preset range; and determining whether there is a DC fault based on the first DC fault count and the second DC fault count.

[0008] Optionally, the first DC fault count and the second DC fault count are statistically obtained when the absolute value of the rotational speed of the object under test is greater than a rotational speed threshold; based on the first DC fault count and the second DC fault count, determining whether there is a DC fault includes: in response to at least one of the first DC fault count and the second DC fault count satisfying a DC fault count condition, determining that a DC fault exists; in response to both the first DC fault count and the second DC fault count not satisfying the DC fault count condition, determining that there is no DC fault.

[0009] Optionally, the first DC fault count and the second DC fault count are statistically obtained when the absolute value of the rotational speed of the object under test is less than or equal to a rotational speed threshold; based on the first DC fault count and the second DC fault count, determining whether there is a DC fault includes: in response to the first DC fault count and the second DC fault count both satisfying the DC fault count condition, determining that a DC fault exists; in response to at least one of the first DC fault count and the second DC fault count not satisfying the DC fault count condition, determining that there is no DC fault.

[0010] Optionally, based on whether the first sampling value at each first sampling moment is within the first preset range, a first DC fault count corresponding to the first AC signal is counted, and based on whether the second sampling value at each first sampling moment is within the first preset range, a second DC fault count corresponding to the second AC signal is counted, including: for the first target sampling value at each first sampling moment, if the first target sampling value is within the first preset range, the target DC fault count is added to the first count value, and if the first target sampling value is outside the first preset range, the target DC fault count is subtracted from the second count value; wherein, when the first target sampling value is the first sampling value, the target DC fault count is the first DC fault count; when the first target sampling value is the second sampling value, the target DC fault count is the second DC fault count.

[0011] Optionally, the sampling data includes a third sampling value of the first AC signal and a fourth sampling value of the second AC signal corresponding to several second sampling moments respectively; based on the sampling data, determining whether the eddy current sensor has a target fault, including: based on the third sampling value and the fourth sampling value of each second sampling moment, determining the verification data corresponding to the first target signal at several verification moments respectively; wherein the verification data includes at least one of a square sum verification result, a DC offset verification result, a peak-to-peak value verification result and an orthogonality verification result, the square sum verification result is used to reflect whether the square sum of the first target signal and the second target signal meets the square sum verification condition, and the DC offset verification result is used to reflect whether the square sum of the first target signal and the second target signal meets the square sum verification condition. The test result is used to reflect whether the DC offset of the first target signal meets the offset verification condition, the peak-to-peak value verification result is used to reflect whether the peak-to-peak value of the first target signal meets the peak-to-peak value verification condition, and the orthogonality verification result is used to reflect whether the first target signal and the second target signal meet the orthogonality verification condition; the first target signal is one of the first AC signal and the second AC signal, and the second target signal is the other of the first AC signal and the second AC signal; based on whether the verification data at each verification moment meets the requirements, the target AC fault count of the first target signal is counted; based on the target AC fault count, it is determined whether there is an AC fault in the eddy current sensor.

[0012] Optionally, the verification moment is the moment when an extreme value of the first target signal is detected.

[0013] Optionally, the step of detecting the extreme value of the first target signal includes: determining whether the current sampling value of the first target signal at the current sampling moment satisfies a preset boundary condition; wherein the current sampling moment is one of a number of second sampling moments, and the preset boundary condition includes: being greater than the latest updated prediction upper boundary or being less than the latest updated prediction lower boundary; if the current sampling value does not satisfy the preset boundary condition, then keeping the prediction upper boundary and the prediction lower boundary unchanged, taking the next second sampling moment of the current sampling moment as the new current sampling moment, and re-executing the determination of whether the current sampling value of the first target signal at the current sampling moment satisfies the preset boundary condition and its subsequent steps; if the current sampling value satisfies the preset boundary condition, then taking the first latch value last updated as the newly updated second latch value, and taking the first prediction direction last updated as the newly updated second latch value. As the newly updated second prediction direction, determine the newly updated first prediction direction based on the size relationship between the current sampling value and the prediction boundary, use the current sampling value as the newly updated first latch value, and determine the newly updated prediction upper boundary and the newly updated prediction lower boundary based on the newly updated first latch value; judge whether the newly updated first prediction direction is the same as the second prediction direction; if the newly updated first prediction direction is the same as the second prediction direction, take the next second sampling moment of the current sampling moment as the new current sampling moment, and re-execute the judgment whether the current sampling value of the first target signal at the current sampling moment meets the preset boundary conditions and its subsequent steps; if the newly updated first prediction direction is not the same as the newly updated second prediction direction, determine the extreme value of the first target signal based on the newly updated first latch value and the newly updated second latch value.

[0014] Optionally, based on the newly updated first latch value and the second latch value, determining the extreme value of the first target signal includes: in response to the newly updated first prediction direction being the first direction and the newly updated second prediction direction being the second direction, determining the minimum value of the first target signal based on the newly updated first latch value and the newly updated second latch value; in response to the newly updated first prediction direction being the second direction and the newly updated second prediction direction being the first direction, determining the maximum value of the first target signal based on the newly updated first latch value and the newly updated second latch value; wherein the first direction is used to characterize that the current sampling value is greater than the newly updated second latch value; and the second direction is used to characterize that the current sampling value is less than the newly updated second latch value.

[0015] Optionally, the target extreme value is the maximum value of the first target signal or the minimum value of the first target signal; based on the newly updated first latch value and the newly updated second latch value, the step of determining the target extreme value includes: using the newly updated first latch value as the target extreme value; or, using the newly updated second latch value as the target extreme value; or, using the combined value of the newly updated first latch value and the second latch value as the target extreme value.

[0016] Optionally, the newly updated first prediction direction is determined based on the size relationship between the current sampling value and the prediction boundary, including: in response to the current sampling value being greater than the latest updated prediction upper boundary, determining the newly updated first prediction direction as the first direction; in response to the current sampling value being less than the latest updated prediction upper boundary, determining the newly updated first prediction direction as the second direction.

[0017] Optionally, a newly updated prediction upper boundary and a newly updated prediction lower boundary are determined based on the newly updated first latch value, including: adding a first preset step size to the newly updated first latch value to obtain a newly updated prediction upper boundary; subtracting a second preset step size from the newly updated first latch value to obtain a newly updated prediction lower boundary.

[0018] Optionally, the verification data includes a square sum verification result, and the step of determining the square sum verification result of the first target signal at the verification moment includes: determining the square sums corresponding to multiple third sampling moments respectively; wherein the multiple third sampling moments are multiple second sampling moments between the previous verification moment of the current verification moment and the current verification moment; in response to the existence of at least one square sum among the square sums of each third sampling moment being outside a preset square sum range, determining that the square sum verification result of the current verification moment does not satisfy the square sum verification condition; in response to the square sums of each third sampling moment being within a preset square sum range, determining that the square sum verification result of the current verification moment satisfies the square sum verification condition.

[0019] Optionally, the verification data includes a target parameter verification result, and the step of determining the target parameter verification result of the first target signal at the verification time includes: obtaining a first extreme value at the current verification time and a second extreme value newly updated before the current verification time; wherein the first extreme value is one of a maximum value and a minimum value, and the second extreme value is the other of a maximum value and a minimum value; determining the target parameter based on the first extreme value and the second extreme value; in response to the target parameter being outside a second preset range, determining that the target parameter verification result at the current verification time does not meet the target parameter verification condition; in response to the target parameter being within the second preset range, determining that the target parameter verification result at the current verification time meets the target parameter verification condition; wherein the target parameter, the second preset range, the target parameter verification result and the target parameter verification condition are respectively a DC offset, a preset offset range, a DC offset verification result and an offset verification condition, or the target parameter, the second preset range, the target parameter verification result and the target parameter verification condition are respectively a peak-to-peak value, a preset peak-to-peak value range, a peak-to-peak value verification result and a peak-to-peak value verification condition.

[0020] Optionally, the verification data includes an orthogonality verification result, and the step of determining the orthogonality verification result of the first target signal at the verification moment includes: obtaining a second target sampling value of the second target signal at the current verification moment; in response to the second target sampling value being outside a third preset range, determining that the orthogonality verification result at the current verification moment does not meet the orthogonality verification condition; in response to the second target sampling value being within the third preset range, determining that the orthogonality verification result at the current verification moment meets the orthogonality verification condition.

[0021] Optionally, based on whether the verification data at each verification moment meets the requirements, the target AC fault count of the first target signal is counted, including: for each verification moment, if there is at least one verification result among the verification results at the verification moment that does not meet the corresponding verification conditions, then the target AC fault count is added with a third count value; if all the verification results at the verification moment meet the corresponding verification conditions, then the target AC fault count is subtracted from a fourth count value.

[0022] Optionally, after determining that a target fault exists, the method further includes: executing a software reset operation to re-execute fault detection; adding a preset number of times to a current reset number; determining whether the current reset number is greater than or equal to a reset number threshold; if the current reset number is less than the reset number threshold, determining whether the target fault is detected again within a preset time window; if the target fault is detected again within the preset time window, re-executing the software reset operation and its subsequent steps; if the target fault is not detected again within the preset time window, subtracting the preset number of times from the current reset number, and re-executing the determination of whether the target fault is detected again within the preset time window and its subsequent steps; if the current reset number is greater than or equal to the reset number threshold, generating a fault protection instruction, which is used to instruct the control of the object under test to stop running.

[0023] To solve the above technical problems, another technical solution adopted in the present application is: to provide a fault detection device for an eddy current sensor, the device comprising: an acquisition module, used to sample a first AC signal and a second AC signal output by the eddy current sensor to obtain sampled data; a fault detection module, used to determine whether the eddy current sensor has a target fault based on the sampled data; wherein the target fault includes at least one of a DC fault and an AC fault; in the event that the eddy current sensor has a DC fault, at least one of the first AC signal and the second AC signal is changed from an AC signal to a DC signal; in the event that the eddy current sensor has an AC fault, at least one of the first AC signal and the second AC signal is changed to an abnormal AC signal.

[0024] To solve the above technical problems, another technical solution adopted in the present application is: to provide an electronic device, comprising a memory and a processor coupled to each other, the memory storing program instructions; the processor is used to execute the program instructions stored in the memory to implement the above-mentioned eddy current sensor fault detection method.

[0025] In order to solve the above technical problems, another technical solution adopted in the present application is: providing a computer-readable storage medium, which is used to store program instructions, and the program instructions can be executed by a processor to implement the above-mentioned eddy current sensor fault detection method.

[0026] The above scheme divides the fault type of the eddy current sensor into DC fault and AC fault according to the difference in the performance characteristics of the first AC signal and the second AC signal after the eddy current sensor fails, and then detects whether the eddy current sensor has a DC fault and an AC fault according to the sampling data of the first AC signal and the second AC signal of the eddy current sensor, thereby realizing fault detection of the eddy current sensor. In this way, the fault type of the eddy current sensor can be detected, which is conducive to quickly determining the fault cause and fault location of the eddy current sensor during maintenance, and improving the maintenance efficiency of the eddy current sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of an embodiment of a fault detection system provided by the present application;

[0028] Figure 2 is a schematic diagram of a first AC signal and a second AC signal of an eddy current sensor provided by the present application;

[0029] Figure 3 It is a flow chart of an embodiment of a fault detection method of an eddy current sensor provided by the present application;

[0030] Figure 4 It is a flow chart of an embodiment of a DC fault detection method for an eddy current sensor provided by the present application;

[0031] Figure 5 It is a flow chart of another embodiment of the DC fault detection method of the eddy current sensor provided by the present application;

[0032] Figure 6 It is a flow chart of an embodiment of a DC fault reset method provided by the present application;

[0033] Figure 7 is a flow chart of another embodiment of the DC fault reset method provided by the present application;

[0034] Figure 8 It is a flow chart of an embodiment of an AC fault detection method for an eddy current sensor provided by the present application;

[0035] Fig. 9 It is a flowchart of an embodiment of an extreme value detection method of a first target signal provided by the present application;

[0036] Fig.10 It is a flow chart of another embodiment of the AC fault detection method of the eddy current sensor provided by the present application;

[0037] Fig.11 It is a flowchart of an embodiment of an AC fault resetting method provided by the present application;

[0038] Fig.12 It is a flowchart of another embodiment of the AC fault resetting method provided by the present application;

[0039] Fig.13 It is a schematic diagram of a framework of an embodiment of a fault detection device for an eddy current sensor provided by the present application;

[0040] Fig.14 It is a schematic diagram of a framework of an embodiment of an electronic device provided by the present application;

[0041] Fig.15 It is a schematic diagram of a framework of an embodiment of a computer-readable storage medium provided by the present application. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and effect of the present application clearer and more specific, the present application is further described in detail below with reference to the accompanying drawings and examples.

[0043] In the following description, for the purpose of explanation rather than limitation, specific details such as specific system structures, interfaces, and technologies are provided to facilitate a thorough understanding of the present application.

[0044] The term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, "many" in this article means two or more than two. In addition, the term "at least one" in this article means any combination of at least two of any one or more of a plurality of. For example, including at least one of A, B, and C, it can mean including any one or more elements selected from the set consisting of A, B and C. "Several" means at least one. The terms "first", "second", etc. in the specification and claims of this article and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0045] See also Figure 1 , Figure 1Schematic diagram of the structure of an embodiment of a fault detection system provided by the present application. Figure 1 As shown, the fault detection system includes an eddy current sensor, a first differential amplifier circuit, a second differential amplifier circuit and a controller. Wherein, the eddy current sensor includes a first signal output terminal, a second signal output terminal, a third signal output terminal, a fourth signal output terminal, a power supply terminal (VCC) and a ground terminal (GND). The first signal output terminal and the second signal output terminal of the eddy current sensor are connected to the differential signal input terminal of the first differential amplifier circuit, and the output terminal of the first differential amplifier circuit is connected to the first sampling terminal of the controller. The third signal output terminal and the fourth signal output terminal of the eddy current sensor are connected to the differential signal input terminal of the second differential amplifier circuit, and the output terminal of the second differential amplifier circuit is connected to the second sampling terminal of the controller. The power supply terminal of the eddy current sensor is connected to the third sampling terminal of the controller, and the ground terminal of the eddy current sensor is connected to the ground terminal of the controller.

[0046] The first signal output terminal and the second signal output terminal of the eddy current sensor are respectively used to output Sin+ (positive sine signal) and Sin- (negative sine signal), that is, sine differential signals. After Sin+ and Sin- are processed by the first differential amplifier circuit, a first AC signal is obtained. The third signal output terminal and the fourth signal output terminal of the eddy current sensor are respectively used to output Cos+ (sine and cosine signal) and Cos- (negative cosine signal), that is, cosine differential signals. After Cos+ and Cos- are processed by the second differential amplifier circuit, a second AC signal is obtained.

[0047] The controller can be an MCU (MicroController Unit), FPGA (Field Programmable Gate Array), PLC (Programmable Logic Controller), etc. The controller can obtain the first AC signal, the second AC signal and the sampling value of the power supply voltage of the eddy current sensor through DSADC (Delta-Sigma analog-to-digital converter) or VADC (programmable analog-to-digital converter), and calculate the angle information of the object to be measured using the sampling value of the first AC signal and the sampling value of the second AC signal. Furthermore, the controller is also used to perform fault detection on the eddy current sensor using the sampling value of the first AC signal and the sampling value of the second AC signal.

[0048] Figure 2 Schematic diagram of the first AC signal and the second AC signal of the eddy current sensor provided by the present application. Figure 2 As shown, when the eddy current sensor is not faulty, the first AC signal is a sine signal, the second AC signal is a cosine signal, the first AC signal and the second AC signal are orthogonal and have a phase difference of 90°.

[0049] After the eddy current sensor fails, the first AC signal and the second AC signal will change. In this embodiment, according to the difference in the performance characteristics of the first AC signal and the second AC signal after the eddy current sensor fails, the fault type of the eddy current sensor is divided into a DC fault and an AC fault, and then the eddy current sensor is detected to determine whether it has a DC fault or an AC fault, thereby realizing fault detection of the eddy current sensor.

[0050] In the case of a DC fault in the eddy current sensor, at least one of the first AC signal and the second AC signal changes from an AC signal to a DC signal. That is, in this fault situation, only the first AC signal may change to a DC signal, or only the second AC signal may change to a DC signal, or both the first AC signal and the second AC signal may change to DC signals. When the first AC signal and / or the second AC signal change to a DC signal, the amplitude of the first AC signal and / or the second AC signal is 0 or there is a certain offset.

[0051] Exemplarily, the combination of fault causes that lead to a DC fault in the eddy current sensor includes: VCC of the eddy current sensor is disconnected and other path signals (including at least one of GND, Sin+, Sin-, Cos+ and Cos- of the eddy current sensor) are disconnected; GND of the eddy current sensor is disconnected and other path signals (including at least one of VCC, Sin+, Sin-, Cos+ and Cos- of the eddy current sensor) are disconnected; Sin+ and Sin- are disconnected at the same time and other path signals (including at least one of VCC, GND, Cos+ and Cos- of the eddy current sensor) are disconnected; Cos+ and Cos- are disconnected at the same time and other path signals (including VCC, GND, at least one of Sin+ and Sin-) is disconnected, and any two signals of the eddy current sensor are short-circuited (short-circuited between Sin+ and Sin-, short-circuited between Cos+ and Cos-, short-circuited between Sin+ and Cos+, short-circuited between Sin+ and Cos-, short-circuited between Sin- and Cos+, short-circuited between Sin- and Cos-, short-circuited between Sin+ and VDD, short-circuited between Sin+ and GND, short-circuited between Sin- and VDD, short-circuited between Sin- and GND, short-circuited between Cos+ and VDD, short-circuited between Cos+ and GND, short-circuited between Cos- and VDD, or short-circuited between Cos- and GND). In other examples, other unknown trigger sources (such as electromagnetic interference, etc.) may also cause DC faults in the eddy current sensor.

[0052] Furthermore, in order to facilitate the subsequent maintenance to quickly determine the fault cause and fault location that caused the eddy current sensor to have a DC fault, the fault cause combination in the above example can be further classified, and the fault cause combination that causes only the first AC signal to become a DC signal is classified into the first category, the fault cause combination that causes only the second AC signal to become a DC signal is classified into the second category, and the fault cause combination that causes both the first AC signal and the second AC signal to become a DC signal is classified into the third category. For example, when it is detected that only the first AC signal is changed to a DC signal, it can be determined that it is caused by the first category of fault cause combination, and then the fault can be troubleshooted based on the first category of fault cause combination.

[0053] In the case of an AC fault in the eddy current sensor, at least one of the first AC signal and the second AC signal becomes an abnormal AC signal. That is, in this fault situation, only the first AC signal may become an abnormal AC signal, or only the second AC signal may become an abnormal AC signal, or both the first AC signal and the second AC signal may become abnormal AC signals. When the first AC signal and / or the second AC signal become abnormal AC signals, the first AC signal and / or the second AC signal still maintain AC characteristics, but the AC characteristic indicators such as amplitude gain, offset, or sum of squares deviate from the normal value range.

[0054] Exemplarily, the combination of fault causes that cause an AC fault in the eddy current sensor includes: only one circuit is broken between Sin+ and Sin-, and only one circuit is broken between Cos+ and Cos-. When only one circuit is broken between Sin+ and Sin-, the first AC signal still appears as a sinusoidal signal; when only one circuit is broken between Cos+ and Cos-, the second AC signal still appears as an AC signal. In other examples, other unknown trigger sources (such as electromagnetic interference, etc.) may also cause an AC fault in the eddy current sensor.

[0055] Furthermore, in order to facilitate the subsequent maintenance to quickly determine the fault cause and fault location that caused the eddy current sensor to have an AC fault, the fault cause combination in the above example can be further classified, and the fault cause combination that causes only the first AC signal to become an abnormal AC signal is classified into the fourth category, the fault cause combination that causes only the second AC signal to become an abnormal AC signal is classified into the fifth category, and the fault cause combination that causes both the first AC signal and the second AC signal to become abnormal AC signals is classified into the sixth category. For example, when it is detected that only the first AC signal has become an abnormal AC signal, it can be determined that it is caused by the fourth category of fault cause combination, and then the fault can be troubleshooted based on the fourth category of fault cause combination.

[0056] See also Figure 3 , Figure 3 is a flow chart of an embodiment of a fault detection method for an eddy current sensor provided by the present application, the method comprising: Figure 1 It should be noted that if there is substantially the same result, the method of the present application is not limited to Figure 1 The process sequence shown is limited. Figure 1 As shown, the method comprises the following steps:

[0057] S31: Sampling the first AC signal and the second AC signal output by the eddy current sensor to obtain sampling data.

[0058] S32: Determine whether the eddy current sensor has a target fault based on the sampled data, where the target fault includes at least one of a DC fault and an AC fault.

[0059] In one embodiment, only the eddy current sensor is detected to see if there is a DC fault.

[0060] In another embodiment, only the eddy current sensor is detected to see if there is an AC fault.

[0061] In another embodiment, it is possible to detect whether the eddy current sensor has a DC fault and whether it has an AC fault. Specifically, in this embodiment, it is possible to first detect whether the eddy current sensor has a DC fault, and then detect whether the eddy current sensor has an AC fault, or it is possible to first detect whether the eddy current sensor has an AC fault, and then detect whether the eddy current sensor has a DC fault. This embodiment does not specifically limit the order of fault detection.

[0062] The definitions of the first AC signal, the second AC signal, the DC fault and the AC fault refer to the above description and will not be repeated here.

[0063] In this embodiment, according to the difference in the performance characteristics of the first AC signal and the second AC signal after the eddy current sensor fails, the fault type of the eddy current sensor is divided into a DC fault and an AC fault, and then the eddy current sensor is detected based on the sampling data of the first AC signal and the second AC signal of the eddy current sensor to detect whether there is a DC fault and an AC fault, thereby realizing the fault detection of the eddy current sensor. In this way, the fault type of the eddy current sensor can be detected, which is conducive to quickly determining the fault cause and fault location of the eddy current sensor during maintenance, and improving the maintenance efficiency of the eddy current sensor.

[0064] In one embodiment, the first AC signal and the second AC signal of the eddy current sensor are sampled to obtain sampling data, and based on the sampling data, it is determined whether the eddy current sensor has a DC fault. In this embodiment, the sampling data includes a first sampling value of the first AC signal and a second sampling value of the second AC signal corresponding to a number of first sampling moments, respectively. It is possible to detect whether the first AC signal has a DC fault based on the first sampling values ​​at the first sampling moments, and detect whether the second AC signal has a DC fault based on the second sampling values ​​at the first sampling moments, thereby determining whether the eddy current sensor has a DC fault. By monitoring the number of times (or the dwell time) that the first sampling value and the second sampling value stay near the zero point to monitor whether the eddy current sensor has a DC fault, the accuracy of the eddy current sensor DC fault detection can be improved.

[0065] See also Figure 4 , Figure 4 FIG. 1 is a flow chart of an embodiment of a DC fault detection method for an eddy current sensor provided by the present application. Figure 4 As shown, the method comprises the following steps:

[0066] S41: Based on whether the first sampling value at each first sampling moment is within the first preset range, counting the first DC fault count corresponding to the first AC signal; and based on whether the second sampling value at each first sampling moment is within the first preset range, counting the second DC fault count corresponding to the second AC signal.

[0067] Wherein, the first preset range is a range near zero. Exemplarily, the first preset range is greater than or equal to zero and less than a preset sampling threshold (Adc_SincosDcLim), and the preset sampling threshold is a value close to zero. When the first sampling value or the second sampling value is within the first preset range, the first sampling value or the second sampling value is considered to be an abnormal sampling value; when the first sampling value or the second sampling value is within the first preset range, the first sampling value or the second sampling value is considered to be a normal sampling value.

[0068] In one embodiment, for the first sampling value at each first sampling moment, if the first sampling value is within the first preset range, the first DC fault count is added to the first count value; if the first sampling value is outside the first preset range, the first DC fault count is not processed. For the second sampling value at each first sampling moment, if the second sampling value is within the first preset range, the second DC fault count is added to the first count value; if the second sampling value is outside the first preset range, the second DC fault count is not processed. In this way, the first DC fault count of the first AC signal and the second DC fault count of the second AC signal are respectively obtained by statistics.

[0069] In another embodiment, for the first sampling value at each first sampling moment, if the first sampling value is within the first preset range, the first count value is added to the first DC fault count; if the first sampling value is outside the first preset range, the second count value is subtracted from the first DC fault count. For the second sampling value at each first sampling moment, if the second sampling value is within the first preset range, the first count value is added to the second DC fault count; if the second sampling value is outside the first preset range, the second count value is subtracted from the second DC fault count. In this way, the first DC fault count of the first AC signal and the second DC fault count of the second AC signal are respectively obtained by statistics.

[0070] In this embodiment, the first count value and the second count value may be the same or different, and the first count value and the second count value may be selected according to actual needs. For example, the first count value and the second count value are both 1. For another example, the first count value is 2 and the second count value is 1. For another example, the first count value is 1 and the second count value is 2.

[0071] In this implementation, when the first sampling value is outside the first preset range, the second count value is subtracted from the first DC fault count, and when the second sampling value is outside the first preset range, the second count value is subtracted from the second DC fault count. This can improve the rationality of the first DC fault count and the second DC fault count, and further improve the reliability and accuracy of DC fault detection.

[0072] S42: Determine whether there is a DC fault in the eddy current sensor based on the first DC fault count and the second DC fault count.

[0073] In step S42, whether the eddy current sensor has a DC fault is determined based on whether the first DC fault count satisfies the DC fault count condition and whether the second DC fault count satisfies the DC fault count condition. The DC fault count condition is that the DC fault count is greater than or equal to the DC fault count threshold (Cnt_DcMax), and the DC fault count threshold is set according to actual needs.

[0074] In one case, the first DC fault count and the second DC fault count are obtained by counting when the absolute value of the rotation speed of the object under test is greater than the rotation speed threshold. In this implementation, when at least one of the first DC fault count and the second DC fault count meets the DC fault count condition, it is determined that the eddy current sensor has a DC fault; when both the first DC fault count and the second DC fault count do not meet the DC fault count condition, it is determined that the eddy current sensor does not have a DC fault.

[0075] In this case, when only the first DC fault count satisfies the DC fault count condition or only the second DC fault count satisfies the DC fault count condition, it is determined that a DC fault exists in a single-channel signal of the eddy current sensor; when both the first DC fault count and the second DC fault count satisfy the DC fault count condition, it is determined that DC faults exist in both channels of the eddy current sensor.

[0076] In another case, the first DC fault count and the second DC fault count are obtained by counting when the absolute value of the rotation speed of the object under test is less than or equal to the rotation speed threshold. When both the first DC fault count and the second DC fault count meet the DC fault count condition, it is determined that the eddy current sensor has a DC fault; when at least one of the first DC fault count and the second DC fault count does not meet the DC fault count condition, it is determined that the eddy current sensor does not have a DC fault.

[0077] In this case, when both the first DC fault count and the second DC fault count satisfy the DC fault count condition, it is determined that DC faults exist in both dual-path signals of the eddy current sensor.

[0078] In the above two situations, the rotation speed of the object under test can be obtained through relevant sensors. For example, when the object under test is a wheel, the rotation speed of the wheel can be obtained through a wheel speed sensor. When the absolute value of the rotation speed of the object under test is less than or equal to the rotation speed threshold, it is considered that the rotation speed of the object under test is low, or the object under test has stopped running.

[0079] It should be noted that if the eddy current sensor is normal, at angles of 0°, 90°, 180°, and 270°, one of the first AC signal and the second AC signal is zero and the other is the maximum value. When the absolute value of the rotational speed of the object being measured is less than or equal to the rotational speed threshold, since the periods of the first AC signal and the second AC signal are lengthened, the first AC signal or the second AC signal at the above-listed angles stays near zero for a long time. In this case, the DC fault count of the detected first AC signal or the second AC signal near zero may easily meet the DC fault count condition. If only the DC fault count of a single signal is detected to meet the DC fault count condition, it is confirmed that the eddy current sensor has a DC fault, which may result in false detection. Therefore, when the absolute value of the rotational speed of the object under test is greater than the rotational speed threshold, the DC fault count of the single signal detected meets the DC fault counting condition, and it is considered that the eddy current sensor has a single signal DC fault. When the absolute value of the rotational speed of the object under test is less than or equal to the rotational speed threshold, the DC fault count of the single signal detected meets the DC fault counting condition, and it is not considered that the eddy current sensor has a single signal DC fault, which can further improve the accuracy of DC fault detection.

[0080] See also Figure 5 , Figure 5FIG. 1 is a flow chart of another embodiment of the DC fault detection method of the eddy current sensor provided by the present application. Figure 5 As shown, the method comprises the following steps:

[0081] S501: Determine whether the rotation speed identifier of the object to be measured is the first rotation speed identifier.

[0082] The rotation speed identifier is a first rotation speed identifier or a second rotation speed identifier. When the rotation speed identifier is the first rotation speed identifier, the absolute value of the rotation speed of the object being measured is greater than the rotation speed threshold; when the rotation speed identifier is the second rotation speed identifier, the absolute value of the rotation speed of the object being measured is less than or equal to the rotation speed threshold. Exemplarily, the first rotation speed identifier is 1 and the second rotation speed identifier is 0.

[0083] If the speed mark is the first speed mark, then step S502 is executed. If the speed mark is the second speed mark, then step S506 is executed.

[0084] S502: Determine whether the first target sampling value at the current sampling moment is within a first preset range.

[0085] If the first target sampling value at the current sampling moment is within the first preset range, step S503 is executed. If the first target sampling value at the current sampling moment is outside the first preset range, step S504 is executed.

[0086] S503: Add the first count value to the target DC fault count.

[0087] S504: Subtract the second count value from the target DC fault count.

[0088] In step S502 to step S504, the current sampling moment is one of the aforementioned first sampling moments. The first target sampling value at the current sampling moment is the first sampling value of the first AC signal or the second sampling value of the second AC signal at the current sampling moment. When the first target sampling value is the first sampling value, the target DC fault count is the first DC fault count; when the first target sampling value is the second sampling value, the target DC fault count is the second DC fault count.

[0089] S505: Determine whether at least one of the first DC fault count and the second DC fault count meets a DC fault count condition.

[0090] If at least one of the first DC fault count and the second DC fault count meets the DC fault count condition, step S510 is executed. If neither the first DC fault count nor the second DC fault count meets the DC fault count condition, the first sampling moment next to the current sampling moment is used as the new current sampling moment, and the aforementioned S502 is executed again.

[0091] Optionally, a first DC fault flag and a second DC fault flag may be further set, the first DC fault flag being used to characterize whether there is a DC fault in the first AC signal, and the second DC fault flag being used to characterize whether there is a DC fault in the second AC signal. In step S505, when the first DC fault count does not meet the DC fault count condition, the first DC fault flag is set to the first DC fault identifier; when the first DC fault count meets the DC fault count condition, the first DC fault flag may be set to the second DC fault identifier. When the second DC fault count does not meet the DC fault count condition, the second DC fault flag may be set to the first DC fault identifier; when the second DC fault count meets the DC fault count condition, the second DC fault flag is set to the second DC fault identifier. Exemplarily, the first DC fault identifier is 0, and the second DC fault identifier is 1. Further, when at least one of the first DC fault flag and the second DC fault flag is the second DC fault identifier, it is determined that there is a DC fault in the eddy current sensor.

[0092] S506: Determine whether the first target sampling value at the current sampling moment is within a first preset range.

[0093] If the first target sampling value at the current sampling moment is within the first preset range, step S507 is executed. If the first target sampling value at the current sampling moment is outside the first preset range, step S508 is executed.

[0094] S507: Add the first count value to the target DC fault count.

[0095] S508: Subtract the second count value from the target DC fault count.

[0096] In step S506 to step S508, the current sampling moment is one of the aforementioned first sampling moments. The first target sampling value at the current sampling moment is the first sampling value of the first AC signal or the second sampling value of the second AC signal at the current sampling moment. When the first target sampling value is the first sampling value, the target DC fault count is the first DC fault count; when the first target sampling value is the second sampling value, the target DC fault count is the second DC fault count.

[0097] S509: Determine whether the first DC fault count and the second DC fault count both meet a DC fault count condition.

[0098] If both the first DC fault count and the second DC fault count meet the DC fault count condition, step S510 is executed. If at least one of the first DC fault count and the second DC fault count does not meet the DC fault count condition, the first sampling moment next to the current sampling moment is used as the new current sampling moment, and the aforementioned S506 is re-executed.

[0099] Optionally, in step S509, when the first DC fault count does not meet the DC fault count condition, the first DC fault flag is set to the first DC fault identifier; when the first DC fault count meets the DC fault count condition, the first DC fault flag is set to the second DC fault identifier. When the second DC fault count does not meet the DC fault count condition, the second DC fault flag is set to the first DC fault identifier; when the second DC fault count meets the DC fault count condition, the second DC fault flag is set to the second DC fault identifier. Further, when both the first DC fault flag and the second DC fault flag are the second DC fault identifiers, it is determined that the eddy current sensor has a DC fault.

[0100] Optionally, in the above step S505 and step S509, to avoid overflow of the counter of the controller, when the first DC fault count or the second DC fault count is greater than the DC fault count threshold, the first DC fault count or the second DC fault count is maintained as the DC fault count threshold.

[0101] S510: Determine that the eddy current sensor has a DC fault.

[0102] Optionally, Figure 4 or Figure 5 In the illustrated embodiment, if the first DC fault count and / or the second DC fault count is greater than or equal to a preset DC count threshold, it is determined that the corresponding first AC signal and / or the second AC signal has a DC fault risk. Exemplarily, the preset DC count threshold is less than the DC fault count threshold, for example, the preset DC count threshold is 80%*DC fault count threshold.

[0103] Optionally, the controller may sample the VCC of the eddy current sensor. When a DC fault is detected in the eddy current sensor and the acquired VCC sampling value is less than a preset sampling value, it is considered that the fault cause combination causing the DC fault in the eddy current sensor includes a VCC open circuit. Fault troubleshooting may be performed based on the fault cause combination related to the VCC open circuit, further improving maintenance efficiency.

[0104] In one embodiment, after the eddy current sensor is detected to have a DC fault, it directly enters a fault protection state. Specifically, a fault protection instruction is generated, and the fault protection instruction is used to instruct the object under test to stop running.

[0105] In another embodiment, in order to prevent temporary DC faults caused by occasional interference from causing abnormal operation of the system, after detecting a DC fault in the eddy current sensor, the system does not enter the fault protection state first, but first performs a fault reset. After the fault reset fails, the system enters the fault protection state. This can effectively avoid the impact of occasional DC faults on the stable operation of the system and make the system have a certain degree of robustness.

[0106] See also Figure 6 , Figure 6 FIG. 1 is a flow chart of an embodiment of a DC fault reset method provided by the present application, which is used to be executed after a DC fault is detected in an eddy current sensor. Figure 6 As shown, the method comprises the following steps:

[0107] S61: Execute a software reset operation to re-execute DC fault detection.

[0108] In step S61, executing the software reset operation means clearing the aforementioned counts and flags related to DC fault detection (such as the first DC fault count, the second DC fault count, the first DC fault flag, and the second DC fault flag, etc.) to zero. After executing the software reset operation, re-execute steps S41 to S42, or re-execute steps S51 to S52 to re-execute DC fault detection.

[0109] S62: Add the current reset times to the preset times.

[0110] Exemplarily, the preset number is 1.

[0111] S63: Determine whether the current reset times is greater than or equal to the DC reset times threshold.

[0112] If the current reset times are less than the DC reset times threshold (Cnt_DcResetMax), step S64 is executed.

[0113] If the current reset times is greater than or equal to the DC reset times threshold, step S66 is executed.

[0114] The DC reset times threshold can be set according to actual needs.

[0115] S64: Determine whether a DC fault is detected again within a preset time window.

[0116] When the current reset number is less than or equal to the DC reset number threshold, a new preset time window is reopened, and then it is determined whether a DC fault is detected again within the new preset time window.

[0117] If the DC fault is detected again within the preset time window, step S61 is executed again.

[0118] If the DC fault is not detected again within the preset time window, step S65 is executed.

[0119] S65: Subtract the preset number of times from the current number of resets.

[0120] Further, after executing step S65, a new preset time window is reopened and S64 is executed again.

[0121] S66: Generate a fault protection instruction.

[0122] The fault protection instruction is used to instruct the object under test to stop running. When the current reset times are greater than or equal to the DC reset times threshold, it is determined that the DC fault reset fails, and the fault protection state is entered.

[0123] See also Figure 7 , Figure 7 FIG. 1 is a flow chart of another embodiment of the DC fault reset method provided by the present application, which is used to perform after a DC fault is detected in the eddy current sensor. Figure 7 As shown, the method comprises the following steps:

[0124] S701: Execute a software reset operation to re-execute DC fault detection.

[0125] S702: Add the current reset times to the preset times.

[0126] S703: Clear the DC timing count.

[0127] Reset the DC timing count to zero to reopen a new preset time window.

[0128] S704: Determine whether the current reset times is greater than or equal to the DC reset times threshold.

[0129] If the current reset times are less than the DC reset times threshold, step S705 is executed.

[0130] If the current reset times is greater than or equal to the DC reset times threshold, step S711 is executed.

[0131] S705: Determine whether a DC fault is detected.

[0132] If a DC fault is detected, step S701 is executed again.

[0133] If no DC fault is detected, step S706 is executed.

[0134] S706: Add the DC timing count to the pre-set value.

[0135] Exemplarily, the preset count value is 1.

[0136] S707: Determine whether the DC timing count is greater than the DC timing threshold.

[0137] If the DC timing count is less than or equal to the DC timing threshold (Cnt_DcLim), step S705 is executed.

[0138] If the DC timing count is greater than the DC timing threshold, step S708 is executed.

[0139] S708: Clear the DC timing count.

[0140] S709: Determine whether the current reset number is greater than the first preset reset number.

[0141] If the current reset number is less than or equal to the first preset reset number, step S705 is executed again.

[0142] If the current reset number is greater than the first preset reset number, step S710 is executed.

[0143] Exemplarily, the first preset reset number is 0.

[0144] S710: Subtract the preset number of times from the current number of resets.

[0145] Further, after executing step S710, step S705 is re-executed to detect whether a DC fault is triggered within a new preset time window.

[0146] S711: Generate a fault protection instruction.

[0147] Among them, the fault protection instruction is used to instruct the object under test to stop running.

[0148] Optionally, in the above step S63 and step S704, in order to prevent the counter of the controller from overflowing, when the current reset number is greater than the DC reset number threshold, the current reset number is maintained at the DC reset number threshold.

[0149] Optionally, Figure 6 or Figure 7 In the illustrated embodiment, during the DC fault reset process, the total number of DC resets is counted, and if the total number of DC resets is greater than a second preset number of resets, it is determined that there is a potential DC fault. Exemplarily, the second preset number of resets is less than a DC reset number threshold, for example, the second preset number of resets is 80%*the DC reset number threshold.

[0150] Further, after determining that the eddy current sensor has a DC fault risk, an early warning message is sent to the terminal device to remind relevant personnel that the eddy current sensor has a DC fault risk. For example, the terminal device can be a mobile phone, computer, vehicle-mounted terminal, etc. of the relevant personnel.

[0151] In one embodiment, the first AC signal and the second AC signal of the eddy current sensor are sampled to obtain sampling data, and whether the eddy current sensor has an AC fault is determined based on the sampling data. In this embodiment, the sampling data includes a third sampling value of the first AC signal and a fourth sampling value of the second AC signal corresponding to a plurality of second sampling moments, and whether the eddy current sensor has an AC fault can be determined based on the sampling data.

[0152] See also Figure 8 , Figure 8 FIG. 1 is a flow chart of an embodiment of an AC fault detection method for an eddy current sensor provided by the present application. Figure 8 As shown, the method comprises the following steps:

[0153] S81: Determine verification data corresponding to the first target signal at a plurality of verification moments based on the third sampling value and the fourth sampling value at each second sampling moment.

[0154] Among them, the verification data at the verification moment includes at least one of the square sum verification result, the DC offset verification result, the peak-to-peak value verification result and the orthogonality verification result at the verification moment. The square sum verification result at the verification moment is used to reflect whether the square sum of the first target signal and the second target signal at the verification moment meets the square sum verification condition. The DC offset verification result at the verification moment is used to reflect whether the DC offset of the first target signal at the verification moment meets the offset verification condition. The peak-to-peak value verification result at the verification moment is used to reflect whether the peak-to-peak value of the first target signal at the verification moment meets the peak-to-peak value verification condition. The orthogonality verification result at the verification moment is used to reflect whether the orthogonality verification condition is met between the first target signal and the second target signal at the verification moment.

[0155] The first target signal is one of the first AC signal and the second AC signal, and the second target signal is the other of the first AC signal and the second AC signal. For example, when the first target signal is the first AC signal, the second target signal is the second AC signal.

[0156] Exemplarily, the verification moment is the moment when the extreme value of the first target signal is detected. That is, each time the maximum value or minimum value of the first target signal is detected, the square sum, DC offset, peak-to-peak value and orthogonality of the first target signal are verified to obtain corresponding verification results.

[0157] See also Fig. 9 , Fig. 9 FIG. 1 is a flow chart of an embodiment of an extreme value detection method of a first target signal provided by the present application. Fig. 9 As shown, the method comprises the following steps:

[0158] S91: Determine whether a current sampling value of the first target signal at a current sampling moment satisfies a preset boundary condition.

[0159] The current sampling time is one of the plurality of second sampling times. The preset boundary conditions include: being greater than the latest updated prediction upper boundary (PreUpValue) or being less than the latest updated prediction lower boundary (PreDownValue).

[0160] If the current sampling value of the first target signal at the current sampling moment does not meet the preset boundary conditions, the predicted upper boundary and the predicted lower boundary are kept unchanged, the next second sampling moment of the current sampling moment is taken as the new current sampling moment, and step S91 is re-executed.

[0161] If the current sampling value of the first target signal at the current sampling moment meets the preset boundary condition, step S92 is executed.

[0162] S92: using the last updated first latch value as the newly updated second latch value, and using the last updated first prediction direction as the newly updated second prediction direction.

[0163] The newly updated second latch value may be represented by SpLockLast, and the newly updated second prediction direction may be represented by PreDirLast.

[0164] S93: Determine a newly updated first prediction direction based on the size relationship between the current sampling value and the prediction boundary.

[0165] If the current sampling value is greater than the latest updated prediction upper boundary, the newly updated first prediction direction is determined to be the first direction. If the current sampling value is less than the latest updated prediction upper boundary, the newly updated first prediction direction is determined to be the second direction. The first direction is used to characterize that the current sampling value is greater than the newly updated second latch value, and the second direction is used to characterize that the current sampling value is less than the newly updated second latch value. Exemplarily, the first direction and the second direction are represented by different direction identifiers, for example, the direction identifier of the first direction is 0, and the direction identifier of the second direction is 1.

[0166] S94: taking the current sampling value as a newly updated first latch value, and determining a newly updated prediction upper boundary and a newly updated prediction lower boundary based on the newly updated first latch value.

[0167] Determining a newly updated prediction upper boundary and a newly updated prediction lower boundary based on the newly updated first latch value includes: adding a first preset step size to the newly updated first latch value to obtain a newly updated prediction upper boundary; subtracting a second preset step size from the newly updated first latch value to obtain a newly updated prediction lower boundary.

[0168] The first preset step size and the second preset step size may be the same or different. The specific values ​​of the first preset step size and the second preset step size may be adaptively set according to the noise of the eddy current sensor. For example, when the noise of the eddy current sensor is large, the first preset step size and the second preset step size may be set to a larger value; when the noise of the eddy current sensor is small, the first preset step size and the second preset step size may be set to a smaller value.

[0169] Exemplarily, the first preset step size and the second preset step size are the same, and the predicted upper boundary and the preset lower boundary can be updated using the following formulas respectively:

[0170] PreUpValue=SpLock+PreStep (1)

[0171] PreDownValue=SpLock-PreStep (2)

[0172] In formula (1) and formula (2), SpLock is the newly updated first latch value.

[0173] S95: Determine whether the newly updated first prediction direction is the same as the second prediction direction.

[0174] If the newly updated first prediction direction is the same as the second prediction direction, the second sampling time next to the current sampling time is taken as the new current sampling time, and step S91 is executed again.

[0175] If the newly updated first prediction direction is different from the newly updated second prediction direction, step S96 is executed.

[0176] S96: Determine an extreme value of the first target signal based on the newly updated first latch value and the newly updated second latch value.

[0177] If the newly updated first prediction direction is the first direction and the newly updated second prediction direction is the second direction, a minimum value of the first target signal is determined based on the newly updated first latch value and the newly updated second latch value.

[0178] If the newly updated first prediction direction is the second direction and the newly updated second prediction direction is the first direction, a maximum value of the first target signal is determined based on the newly updated first latch value and the newly updated second latch value.

[0179] The maximum value and the minimum value of the first target signal are determined in the same manner. It is assumed that the target extreme value is the maximum value of the first target signal or the minimum value of the first target signal.

[0180] In one example, the newly updated first latch value (ie, SpLock) is directly used as the target extreme value.

[0181] In another example, the newly updated second latch value (ie, SpLockLast) is directly used as the target extreme value.

[0182] In another example, the integrated value of the newly updated first latch value and the second latch value is used as the target extreme value. For example, the average value, weighted value, etc. of the newly updated first latch value and the newly updated second latch value is used as the target extreme value.

[0183] Furthermore, the maximum value and minimum value of the first target signal are latched in the storage unit of the controller. When the maximum value of the first target signal is newly detected, the latched maximum value is updated to the newly detected maximum value, and the latched minimum value remains unchanged; when the minimum value of the first target signal is newly detected, the latched minimum value is updated to the newly detected minimum value, and the latched maximum value remains unchanged.

[0184] Considering that if the direct derivation method is used, the value may increase and decrease from time to time, and the extreme value of the first target signal obtained is greatly affected by noise, and the extreme value of the first target signal obtained by the time window detection method will fail due to the frequency change of the object being measured, especially in the low-frequency state, in steps S91 to S96, the new prediction direction and the new prediction upper boundary and the new prediction lower boundary are updated and iterated by detecting the size relationship between the sampling value of the first target signal at the current sampling moment and the prediction upper boundary and the prediction lower boundary, and whether the maximum value or minimum value is detected is determined by detecting whether the two adjacent prediction directions have changed. On the one hand, this method can flexibly set the iteration step size according to the actual noise situation of the eddy current sensor, has strong adaptability, and improves the accuracy of the extreme value of the first target signal obtained. On the other hand, this method is not affected by the frequency of the rotation noise of the object being measured, and is applicable under any frequency, any amplitude, and any offset conditions.

[0185] In one embodiment, the verification data includes a square sum verification result, and the step of determining the square sum verification result of the first target signal at the verification time includes: determining the square sums corresponding to a plurality of third sampling moments; when at least one square sum among the square sums of the third sampling moments is outside a preset square sum range, determining that the square sum verification result at the current verification time does not satisfy the square sum verification condition; when the square sums of the third sampling moments are all within a preset square sum range, determining that the square sum verification result at the current verification time satisfies the square sum verification condition. The plurality of third sampling moments are a plurality of second sampling moments between a previous verification moment of the current verification moment and the current verification moment.

[0186] The sum of the squares of the third sampling moments can be determined using the following formula:

[0187] SS=Sin 2 +Cos 2 (3)

[0188] In formula (3), Sin represents the third sampling value of the first AC signal at the third sampling moment, and Cos represents the fourth sampling value of the second AC signal at the third sampling moment.

[0189] Exemplarily, the preset square sum range is: greater than the first preset square sum and less than the second preset square sum. The first preset square sum is a preset square sum minimum value (SSMin), and the second preset square sum is a preset square sum maximum value (SSMax). The first preset square sum and the second preset square sum can be obtained by setting a certain margin on the basis of the actual measured signal range of the eddy current sensor.

[0190] In this embodiment, the square sum of the first target signal is obtained at each sampling moment between two adjacent verification moments, and if the square sum of at least one sampling moment exceeds the limit, it is determined that the square sum verification result at the current verification moment does not meet the square sum verification condition, which can improve the accuracy of square sum over-limit detection.

[0191] In one embodiment, the verification data includes a target parameter verification result, and determining the target parameter verification result of the first target signal at the verification time includes the following sub-steps:

[0192] Sub-step 1, obtaining the first extreme value at the current verification moment and the second extreme value newly updated before the current verification moment.

[0193] The first extreme value is one of a maximum value and a minimum value, and the second extreme value is the other of a maximum value and a minimum value.

[0194] Sub-step two: determining the target parameter based on the first extreme value and the second extreme value.

[0195] When the target parameter is the DC offset, the DC offset can be calculated using the following formula:

[0196] offSet=0.5*(Max+Min) (4)

[0197] When the target parameter is the peak-to-peak value, the peak-to-peak value can be calculated using the following formula:

[0198] PP=Max-Min (5)

[0199] In formula (4) and formula (5), when Max is the maximum value at the current verification time, Min is the minimum value newly updated before the current verification time; when Min is the minimum value at the current verification time, Max is the maximum value newly updated before the current verification time.

[0200] Sub-step three: determining whether the target parameter verification result at the current verification moment meets the target parameter verification condition based on whether the target parameter is within the second preset range.

[0201] When the target parameter is outside the second preset range, it is determined that the target parameter verification result at the current verification time does not meet the target parameter verification condition; when the target parameter is within the second preset range, it is determined that the target parameter verification result at the current verification time meets the target parameter verification condition.

[0202] In the case where the target parameter is a DC offset, the second preset range, the target parameter verification result, and the target parameter verification condition are the preset offset range, the DC offset verification result, and the offset verification condition, respectively. Exemplarily, the preset offset range is: greater than the first preset offset and less than the second preset offset. The first preset offset is a preset minimum offset value (OffsetMin), and the second preset offset is a preset maximum offset value (OffsetMin). The first preset offset and the second preset offset can be obtained by setting a certain margin on the basis of the actual measured signal range of the eddy current sensor.

[0203] In the case where the target parameter is a peak-to-peak value, the second preset range, the target parameter verification result, and the target parameter verification condition are respectively a preset peak-to-peak value range, a peak-to-peak value verification result, and a peak-to-peak value verification condition. Exemplarily, the preset peak-to-peak value range is: greater than the first preset peak-to-peak value and less than the second preset peak-to-peak value. The first preset peak-to-peak value is a preset peak-to-peak value minimum value (PPMin), and the second preset peak-to-peak value is a preset peak-to-peak value maximum value (PPMin). The first preset peak-to-peak value and the second preset peak-to-peak value can be obtained by setting a certain margin on the basis of the actual measured signal range of the eddy current sensor.

[0204] In one embodiment, the verification data includes an orthogonality verification result, and the step of determining the orthogonality verification result of the first target signal at the verification time includes: obtaining a second target sampling value of the second target signal at the current verification time; when the second target sampling value is outside a third preset range, determining that the orthogonality verification result at the current verification time does not meet the orthogonality verification condition; when the second target sampling value is within the third preset range, determining that the orthogonality verification result at the current verification time meets the orthogonality verification condition.

[0205] When the first target signal is the first AC signal, the second target sampling value of the second AC signal at the current verification moment is obtained. At this time, the third preset range is greater than the first preset cosine value and less than the second preset cosine value. When the first target signal is the second AC signal, the second target sampling value of the first AC signal at the current verification moment is obtained. At this time, the third preset range is greater than the first preset sine value and less than the second preset sine value. Exemplarily, the first preset cosine value and the first preset sine value are the same, both of which are the set orthogonality check minimum value (OrtLimMin), the second preset cosine value and the second preset sine value are the same, both are the set orthogonality check maximum value (OrtLimMax), and the orthogonality check minimum value and the orthogonality check maximum value can be obtained after setting a certain margin on the basis of the measured signal range of the eddy current sensor.

[0206] S82: Based on whether the verification data at each verification moment meets the requirements, counting the target AC fault count of the first target signal.

[0207] For each verification moment, if there is at least one verification result among the verification results at the verification moment that does not meet the corresponding verification conditions, the target AC fault count is added with the third count value; if all the verification results at the verification moment meet the corresponding verification conditions, the target AC fault count is subtracted from the fourth count value.

[0208] The third count value and the fourth count value may be the same or different. For example, the third count value and the fourth count value are both 1. For another example, the third count value is 2 and the fourth count value is 1. For another example, the third count value is 1 and the fourth count value is 2.

[0209] When the first target signal is a first AC signal, the target AC fault count is a first AC fault count corresponding to the first AC signal. When the first target signal is a second AC signal, the target AC fault count is a second AC fault count corresponding to the first AC signal. In step S82, the first AC fault count of the first AC signal and the second AC fault count of the second AC signal are counted simultaneously.

[0210] In step S82, when there is at least one verification result among the verification results at the verification time that does not meet the corresponding verification conditions, the target AC fault count is added with the third count value; when the verification results at the verification time all meet the corresponding verification conditions, the target AC fault count is subtracted from the fourth count value, which can improve the rationality of the target AC fault count and further improve the reliability and accuracy of AC fault detection.

[0211] S83: Determine whether the eddy current sensor has an AC fault based on the target AC fault count.

[0212] In step S83, it is determined whether there is an AC fault in the eddy current sensor based on whether the first AC fault count and the second AC fault count meet an AC fault count condition, wherein the AC fault count condition is that the AC fault count is greater than or equal to an AC fault count threshold, and the AC fault count threshold can be set according to actual needs.

[0213] When the first AC fault count satisfies the AC fault count condition, the first AC signal has an AC fault; when the second AC fault count satisfies the AC fault count condition, the second AC signal has an AC fault; when both the first AC fault count and the second AC fault count satisfy the AC fault count condition, both the first AC signal and the second AC signal have AC faults. That is, when at least one of the first AC fault count and the second AC fault count satisfies the AC fault count condition, it is determined that the eddy current sensor has an AC fault.

[0214] When both the first AC fault count and the second AC fault count do not satisfy the AC fault count condition, it is determined that there is no AC fault in the eddy current sensor.

[0215] See also Fig.10 , Fig.10 FIG. 1 is a flow chart of another embodiment of the AC fault detection method of the eddy current sensor provided by the present application. Fig.10 As shown, the method comprises the following steps:

[0216] S101: Based on current sampling values ​​of the first target signal and the second target signal at the current sampling moment, obtain the square sum at the current sampling moment.

[0217] The current sampling time is one of the aforementioned second sampling times.

[0218] S102: Determine whether the sum of squares at the current sampling moment is within a preset sum of squares range.

[0219] If the sum of squares at the current sampling moment is within the preset sum of squares range, step S104 is executed.

[0220] If the sum of squares at the current sampling moment is outside the preset sum of squares range, step S103 is executed.

[0221] S103: Set the square sum over-limit flag bit to an over-limit flag.

[0222] Exemplarily, the over-limit flag is 1.

[0223] Further, after executing step S103, execute step S104.

[0224] S104: Determine whether an extreme value of the first target signal is detected at the current sampling moment.

[0225] If the extreme value of the first target signal is not detected at the current sampling moment, the next second sampling moment of the current sampling moment is used as the new current sampling moment, and step S101 is executed again.

[0226] If the extreme value of the first target signal is detected at the current sampling moment, step S105 is executed.

[0227] For more information on detecting the extreme value of the first target signal, please refer to Fig. 9 The embodiments shown will not be described in detail here.

[0228] S105: Taking the extreme value at the current sampling moment as the first extreme value at the current verification moment, and determining the DC offset and peak-to-peak value at the current verification moment based on the first extreme value at the current verification moment and the second extreme value newly updated before the current verification moment.

[0229] The determination of the DC offset and the peak-to-peak value based on the first extreme value and the second extreme value can be referred to the description of the aforementioned related contents, which will not be repeated here.

[0230] S106: Obtain the square sum verification result, DC offset verification result, peak-to-peak value verification result and orthogonality verification result at the current verification moment.

[0231] To obtain the results of each verification, please refer to the description of the relevant content above, which will not be repeated here.

[0232] S107: Based on the square sum check result, the DC offset check result, the peak-to-peak value check result and the orthogonality check result at the current check time, counting the target AC fault count of the first target signal.

[0233] If at least one of the inspection results at the current verification moment does not meet the corresponding verification conditions, the target AC fault count is increased by the third count value; if all the inspection results at the current verification moment meet the corresponding verification conditions, the target AC fault count is subtracted by the fourth count value.

[0234] S108: Determine whether the target AC fault count of the first target signal satisfies an AC fault count condition.

[0235] If the target AC fault count of the first target signal does not satisfy the AC fault count condition, the second sampling moment next to the current sampling moment is used as a new current sampling moment, and step S101 is executed again.

[0236] If the target AC fault count of the first target signal meets the AC fault count condition, step S109 is executed.

[0237] Optionally, in step S108, a target AC fault flag may be further set. When the first target signal is a first AC signal, the target AC fault flag is a first AC fault flag corresponding to the first AC signal. When the first target signal is a second AC signal, the target AC fault flag is a second AC fault flag corresponding to the second AC signal. The first AC fault flag is used to characterize whether there is an AC fault in the first AC signal, and the second AC fault flag is used to characterize whether there is an AC fault in the second AC signal. In step S108, when the first AC fault count does not meet the AC fault count condition, the first AC fault flag is set to the first AC fault identifier; when the first AC fault count meets the AC fault count condition, the first AC fault flag may be set to the second AC fault identifier. When the second AC fault count does not meet the AC fault count condition, the second AC fault flag may be set to the first AC fault identifier; when the second AC fault count meets the AC fault count condition, the second AC fault flag is set to the second AC fault identifier. Exemplarily, the first AC fault identifier is 0, and the second AC fault identifier is 1. Further, when at least one of the first AC fault flag bit and the second AC fault flag bit is a second AC fault identifier, it is determined that an AC fault exists in the eddy current sensor.

[0238] Optionally, in the above step S83 and step S108, to avoid overflow of the counter of the controller, when the target AC fault count is greater than the AC fault count threshold, the target AC fault count is maintained at the AC fault count threshold.

[0239] S109: Determine that the eddy current sensor has an AC fault.

[0240] Optionally, Figure 8 or Fig.10 In the illustrated embodiment, if the target AC fault count of the first target signal (the first AC signal or the second AC signal) is greater than or equal to a preset AC count threshold, it is determined that the first target signal has an AC fault risk. Exemplarily, the preset AC count threshold is less than the AC fault count threshold, for example, the preset AC count threshold is 80%*AC fault count threshold.

[0241] In one embodiment, after detecting that an AC fault exists in the eddy current sensor, the sensor enters a fault protection state, specifically, generates a fault protection instruction, which is used to instruct the object under test to stop running.

[0242] In another embodiment, in order to prevent temporary AC faults caused by occasional interference from causing abnormal operation of the system, after detecting an AC fault in the eddy current sensor, the system does not enter the fault protection state first, but performs a fault reset first. After the fault reset fails, the system enters the fault protection state. This can effectively avoid the impact of occasional AC faults on the stable operation of the system and make the system have a certain degree of robustness.

[0243] See also Fig.11 , Fig.11 FIG. 1 is a flow chart of an embodiment of an AC fault reset method provided by the present application, which is used to be executed after an AC fault is detected in an eddy current sensor. Fig.11 As shown, the method comprises the following steps:

[0244] S111: Execute a software reset operation to re-execute AC fault detection.

[0245] In step S111, executing the software reset operation means clearing the aforementioned counts and flags related to AC fault detection (such as the first AC fault count, the second AC fault count, the first AC fault flag, and the second AC fault flag, etc.). After executing the software reset operation, re-execute steps S81 to S83, or re-execute steps S101 to S109 to re-execute AC fault detection.

[0246] S112: Add the current reset times to the preset times.

[0247] Exemplarily, the preset number is 1.

[0248] S113: Determine whether the current reset times is greater than or equal to the AC reset times threshold.

[0249] If the current reset times are less than the AC reset times threshold, step S114 is executed.

[0250] If the current reset times are greater than or equal to the AC reset times threshold, step S116 is executed.

[0251] The AC reset times threshold can be set according to actual needs.

[0252] S114: Determine whether the AC fault is detected again within the preset time window.

[0253] When the current reset number is less than or equal to the AC reset number threshold, a new preset time window is reopened, and then it is determined whether an AC fault is detected again within the new preset time window.

[0254] If the AC fault is detected again within the preset time window, step S111 is executed again.

[0255] If the AC fault is not detected again within the preset time window, step S115 is executed.

[0256] In step S114, the preset time window for resetting the AC fault can be set according to the rotation period of the object to be detected, so as to monitor whether the AC fault is triggered again within a specific number of rotation periods. The rotation period of the object to be detected has a multiple relationship with the number of extreme value points detected.

[0257] S115: Subtract the preset number of times from the current number of resets.

[0258] Further, after executing step S115, a new preset time window is reopened and S114 is executed again.

[0259] S116: Generate a fault protection instruction.

[0260] Among them, the fault protection instruction is used to instruct the object under test to stop running.

[0261] See also Fig.12 , Fig.12 FIG. 1 is a flow chart of another embodiment of the AC fault reset method provided by the present application, which is used to perform after detecting that an AC fault exists in the eddy current sensor. Fig.12 As shown, the method comprises the following steps:

[0262] S1201: Execute a software reset operation to re-execute AC fault detection.

[0263] S1202: Add the current reset times to the preset times.

[0264] S1203: Clear the extreme point count.

[0265] Restart a new specific rotation cycle by clearing the extreme point count to zero.

[0266] S1204: Determine whether the current reset times is greater than or equal to the AC reset times threshold.

[0267] If the current reset times are less than the AC reset times threshold, step S1205 is executed.

[0268] If the current reset times are greater than or equal to the AC reset times threshold, step S1212 is executed.

[0269] S1205: Determine whether an extreme value is detected.

[0270] If an extreme value is detected, step S1206 is executed.

[0271] If no extreme value is detected, step S1205 is executed again.

[0272] S1206: Determine whether an AC fault is detected.

[0273] If an AC fault is detected, step S1201 is executed again.

[0274] If no AC fault is detected, step S1207 is executed.

[0275] S1207: Add the extreme point count to a pre-designed value.

[0276] Exemplarily, the preset count value is 1.

[0277] S1208: Determine whether the extreme value point count is greater than the extreme value point count threshold.

[0278] If the extreme point count is less than or equal to the extreme point count threshold, step S1205 is executed.

[0279] If the extreme point count is greater than the extreme point count threshold, step S1209 is executed.

[0280] The extreme point counting threshold can be set according to the rotation period of the object being measured.

[0281] S1209: Clear the extreme point count.

[0282] S1210: Determine whether the current reset number is greater than a first preset reset number.

[0283] If the current reset number is less than or equal to the first preset reset number, step S1205 is executed again.

[0284] If the current reset times are greater than the first preset reset times, step S1211 is executed.

[0285] Exemplarily, the first preset reset number is 0.

[0286] S1211: Subtract the preset number of times from the current number of resets.

[0287] Further, after executing step S1211, step S1205 is re-executed to detect whether the AC fault is triggered again in a new specific rotation cycle.

[0288] S1212: Generate a fault protection instruction.

[0289] Among them, the fault protection instruction is used to instruct the object under test to stop running.

[0290] Optionally, in the above step S113 and step S1204, in order to prevent the counter of the controller from overflowing, when the current reset number is greater than the AC reset number threshold, the current reset number is maintained at the AC reset number threshold.

[0291] Optionally, Fig.11 or Fig.12 In the illustrated embodiment, during the process of resetting the AC fault, the total number of AC resets is counted, and if the total number of AC resets is greater than a third preset number of resets, it is determined that there is an AC fault hazard. Exemplarily, the third preset number of resets is less than an AC reset number threshold, for example, the third preset number of resets is 80%*AC reset number threshold.

[0292] Further, after determining that the eddy current sensor has an AC fault risk, an early warning message is sent to the terminal device to remind relevant personnel that the eddy current sensor has an AC fault risk.

[0293] In the related art, the eddy current sensor is usually removed from the equipment for fault detection separately, which is not only time-consuming and laborious, but also may cause secondary damage to the eddy current sensor during the disassembly and installation process. Fault detection relies on complex equipment and professional technicians, which increases the detection cost and difficulty. In this embodiment, according to the different performance characteristics of the first AC signal and the second AC signal after the eddy current sensor fails, the fault type of the eddy current sensor is divided into DC fault and AC fault, and then the eddy current sensor is detected based on the sampling data of the first AC signal and the second AC signal of the eddy current sensor to detect whether there is a DC fault and an AC fault, so as to realize the fault detection of the eddy current sensor. On the one hand, the eddy current sensor can be fault-detected in real time during the operation of the eddy current sensor, and potential fault hazards can be discovered in time; on the other hand, the fault type of the eddy current sensor can be detected, which is conducive to quickly determining the fault cause and fault location of the eddy current sensor during maintenance, and improving the maintenance efficiency of the eddy current sensor.

[0294] See also Fig.13 , Fig.13 It is a schematic diagram of the framework of an embodiment of a fault detection device for an eddy current sensor provided by the present application. In this embodiment, the fault detection device 130 for an eddy current sensor includes: an acquisition module 1301 and a fault detection module 1302. The acquisition module 1301 is used to sample the first AC signal and the second AC signal output by the eddy current sensor to obtain sampled data. The fault detection module 1302 is used to determine whether the eddy current sensor has a target fault based on the sampled data. Among them, the target fault includes at least one of a DC fault and an AC fault; in the case of a DC fault in the eddy current sensor, at least one of the first AC signal and the second AC signal changes from an AC signal to a DC signal; in the case of an AC fault in the eddy current sensor, at least one of the first AC signal and the second AC signal changes to an abnormal AC signal.

[0295] Optionally, the sampling data includes a first sampling value of a first AC signal and a second sampling value of a second AC signal respectively corresponding to a plurality of first sampling moments. The fault detection module 1302 is used to count a first DC fault count corresponding to the first AC signal based on whether the first sampling value at each first sampling moment is within a first preset range, and to count a second DC fault count corresponding to the second AC signal based on whether the second sampling value at each first sampling moment is within the first preset range; and to determine whether a DC fault exists based on the first DC fault count and the second DC fault count.

[0296] Optionally, the first DC fault count and the second DC fault count are obtained by counting when the absolute value of the rotation speed of the object under test is greater than the rotation speed threshold. The fault detection module 1302 is used to determine that a DC fault exists in response to at least one of the first DC fault count and the second DC fault count satisfying a DC fault count condition; and determine that a DC fault does not exist in response to both the first DC fault count and the second DC fault count not satisfying the DC fault count condition.

[0297] Optionally, the first DC fault count and the second DC fault count are obtained by counting when the absolute value of the rotation speed of the object under test is less than or equal to the rotation speed threshold. The fault detection module 1302 is used to determine that a DC fault exists in response to both the first DC fault count and the second DC fault count satisfying a DC fault count condition; and determine that a DC fault does not exist in response to at least one of the first DC fault count and the second DC fault count not satisfying the DC fault count condition.

[0298] Optionally, the fault detection module 1302 is used to add the first count value to the target DC fault count for the first target sampling value at each first sampling moment if the first target sampling value is within the first preset range; if the first target sampling value is outside the first preset range, subtract the second count value from the target DC fault count; wherein, when the first target sampling value is the first sampling value, the target DC fault count is the first DC fault count; when the first target sampling value is the second sampling value, the target DC fault count is the second DC fault count.

[0299] Optionally, the sampling data includes a third sampling value of the first AC signal and a fourth sampling value of the second AC signal corresponding to a plurality of second sampling moments. The fault detection module 1302 is used to determine the verification data corresponding to the first target signal at a plurality of verification moments based on the third sampling value and the fourth sampling value at each second sampling moment; wherein the verification data includes at least one of a square sum verification result, a DC offset verification result, a peak-to-peak value verification result, and an orthogonality verification result, the square sum verification result is used to reflect whether the square sum of the first target signal and the second target signal meets the square sum verification condition, the DC offset verification result is used to reflect whether the DC offset of the first target signal meets the offset verification condition, the peak-to-peak value verification result is used to reflect whether the peak-to-peak value of the first target signal meets the peak-to-peak value verification condition, and the orthogonality verification result is used to reflect whether the first target signal meets the orthogonality verification condition between the first target signal and the second target signal; the first target signal is one of the first AC signal and the second AC signal, and the second target signal is the other of the first AC signal and the second AC signal; based on whether the verification data at each verification moment meets the requirements, the target AC fault count of the first target signal is counted; based on the target AC fault count, it is determined whether the eddy current sensor has an AC fault.

[0300] Optionally, the verification moment is the moment when an extreme value of the first target signal is detected.

[0301] Optionally, the fault detection module 1302 is used to determine whether the current sampling value of the first target signal at the current sampling moment meets the preset boundary conditions; wherein the current sampling moment is one of a number of second sampling moments, and the preset boundary conditions include: being greater than the latest updated prediction upper boundary or being less than the latest updated prediction lower boundary; if the current sampling value does not meet the preset boundary conditions, the prediction upper boundary and the prediction lower boundary are kept unchanged, and the next second sampling moment of the current sampling moment is used as the new current sampling moment, and the determination of whether the current sampling value of the first target signal at the current sampling moment meets the preset boundary conditions and subsequent steps are re-executed; if the current sampling value meets the preset boundary conditions, the first latch value updated last time is used as the newly updated second latch value, and the first prediction direction updated last time is used as the new An updated second prediction direction is determined based on the size relationship between the current sampling value and the prediction boundary, the new updated first prediction direction is determined, the current sampling value is used as the new updated first latch value, and the new updated prediction upper boundary and the new updated prediction lower boundary are determined based on the new updated first latch value; it is judged whether the new updated first prediction direction is the same as the second prediction direction; if the new updated first prediction direction is the same as the second prediction direction, the next second sampling moment of the current sampling moment is used as the new current sampling moment, and the judgment of whether the current sampling value of the first target signal at the current sampling moment meets the preset boundary conditions and its subsequent steps are re-executed; if the new updated first prediction direction is not the same as the new updated second prediction direction, the extreme value of the first target signal is determined based on the new updated first latch value and the new updated second latch value.

[0302] Optionally, the fault detection module 1302 is used to determine the minimum value of the first target signal based on the newly updated first latch value and the newly updated second latch value in response to the newly updated first prediction direction being the first direction and the newly updated second prediction direction being the second direction; determine the maximum value of the first target signal based on the newly updated first latch value and the newly updated second latch value in response to the newly updated first prediction direction being the second direction and the newly updated second prediction direction being the first direction; wherein the first direction is used to characterize that the current sampling value is greater than the newly updated second latch value; and the second direction is used to characterize that the current sampling value is less than the newly updated second latch value.

[0303] Optionally, the target extreme value is the maximum value of the first target signal or the minimum value of the first target signal; the fault detection module 1302 is used to use the newly updated first latch value as the target extreme value; or, use the newly updated second latch value as the target extreme value; or, use the combined value of the newly updated first latch value and the second latch value as the target extreme value.

[0304] Optionally, the fault detection module 1302 is used to determine the newly updated first prediction direction as the first direction in response to the current sampling value being greater than the latest updated prediction upper boundary; in response to the current sampling value being less than the latest updated prediction upper boundary, determine the newly updated first prediction direction as the second direction.

[0305] Optionally, the fault detection module 1302 is configured to add a first preset step size to the newly updated first latch value to obtain a newly updated prediction upper boundary; and subtract a second preset step size from the newly updated first latch value to obtain a newly updated prediction lower boundary.

[0306] Optionally, the verification data includes a square sum verification result, and the fault detection module 1302 is used to determine the square sums corresponding to multiple third sampling moments respectively; wherein the multiple third sampling moments are multiple second sampling moments between the previous verification moment of the current verification moment and the current verification moment; in response to the existence of at least one square sum among the square sums of each third sampling moment being outside a preset square sum range, it is determined that the square sum verification result of the current verification moment does not meet the square sum verification condition; in response to the square sums of each third sampling moment being within a preset square sum range, it is determined that the square sum verification result of the current verification moment meets the square sum verification condition.

[0307] Optionally, the verification data includes a target parameter verification result, and the fault detection module 1302 is used to obtain a first extreme value at the current verification moment and a second extreme value newly updated before the current verification moment; wherein the first extreme value is one of a maximum value and a minimum value, and the second extreme value is the other of a maximum value and a minimum value; based on the first extreme value and the second extreme value, the target parameter is determined; in response to the target parameter being outside a second preset range, the target parameter verification result at the current verification moment is determined to not meet a target parameter verification condition; in response to the target parameter being within a second preset range, the target parameter verification result at the current verification moment is determined to meet a target parameter verification condition; wherein the target parameter, the second preset range, the target parameter verification result and the target parameter verification condition are respectively a DC offset, a preset offset range, a DC offset verification result and an offset verification condition, or the target parameter, the second preset range, the target parameter verification result and the target parameter verification condition are respectively a peak-to-peak value, a preset peak-to-peak value range, a peak-to-peak value verification result and a peak-to-peak value verification condition.

[0308] Optionally, the verification data includes an orthogonality verification result, and the fault detection module 1302 is used to obtain a second target sampling value of the second target signal at the current verification moment; in response to the second target sampling value being outside a third preset range, it is determined that the orthogonality verification result at the current verification moment does not meet the orthogonality verification condition; in response to the second target sampling value being within the third preset range, it is determined that the orthogonality verification result at the current verification moment meets the orthogonality verification condition.

[0309] Optionally, the fault detection module 1302 is used to, for each verification moment, if at least one of the verification results at the verification moment does not satisfy the corresponding verification condition, add a third count value to the target AC fault count; if all the verification results at the verification moment satisfy the corresponding verification condition, subtract a fourth count value from the target AC fault count.

[0310] Optionally, the fault detection device 130 also includes a fault reset module 1303. After the fault detection module 1302 determines that there is a target fault, the fault reset module 1303 is used to perform a software reset operation to re-execute fault detection; add a preset number of times to the current reset number; determine whether the current reset number is greater than or equal to the reset number threshold; if the current reset number is less than the reset number threshold, determine whether the target fault is detected again within the preset time window; if the target fault is detected again within the preset time window, re-execute the software reset operation and its subsequent steps; if the target fault is not detected again within the preset time window, subtract the preset number of times from the current reset number, and re-execute the determination of whether the target fault is detected again within the preset time window and its subsequent steps; if the current reset number is greater than or equal to the reset number threshold, generate a fault protection instruction, which is used to instruct the control of the object under test to stop running.

[0311] It should be noted that the device of this embodiment can execute the steps in the above method. For detailed description of the relevant content, please refer to the above method part, which will not be repeated here.

[0312] See also Fig.14 , Fig.14 140 is a schematic diagram of a framework of an electronic device according to an embodiment of the present application. In this embodiment, the electronic device 140 includes a memory 1401 and a processor 1402 .

[0313] The processor 1402 may also be referred to as a CPU (Central Processing Unit). The processor 1402 may be an integrated circuit chip having signal processing capabilities. The processor 1402 may also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. A general-purpose processor may be a microprocessor or the processor 1402 may also be any conventional processor 1402, etc.

[0314] The memory 1401 in the electronic device 140 is used to store program instructions required for the processor 1402 to run.

[0315] The processor 1402 is used to execute program instructions to implement the fault detection method of the eddy current sensor in the present application.

[0316] See also Fig.15 , Fig.15 It is a schematic diagram of a framework of an embodiment of a computer-readable storage medium provided by the present application. The computer-readable storage medium 150 of the embodiment of the present application stores a program instruction 1501, and the program instruction 1501 implements the fault detection method of the eddy current sensor provided by the present application when it is executed. Among them, the program instruction 1501 can form a program file and be stored in the above-mentioned computer-readable storage medium 150 in the form of a software product, so that a computer device (which can be a personal computer, a server, or a network device, etc.) executes all or part of the steps of each implementation method of the present application. The aforementioned computer-readable storage medium 150 includes: various media that can store program codes, such as a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a disk or an optical disk, or a terminal device such as a computer, a server, a mobile phone, and a tablet.

[0317] The above scheme divides the fault type of the eddy current sensor into DC fault and AC fault according to the difference in the performance characteristics of the first AC signal and the second AC signal after the eddy current sensor fails, and then detects whether the eddy current sensor has a DC fault and an AC fault according to the sampling data of the first AC signal and the second AC signal of the eddy current sensor, thereby realizing fault detection of the eddy current sensor. In this way, the fault type of the eddy current sensor can be detected, which is conducive to quickly determining the fault cause and fault location of the eddy current sensor during maintenance, and improving the maintenance efficiency of the eddy current sensor.

[0318] In some embodiments, the functions or modules included in the device provided by the embodiments of the present disclosure can be used to execute the method described in the above method embodiments. The specific implementation can refer to the description of the above method embodiments, and for the sake of brevity, it will not be repeated here.

[0319] The above description of various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced to each other, and for the sake of brevity, they will not be repeated herein.

[0320] In the several embodiments provided in the present application, it should be understood that the disclosed methods, devices and systems can be implemented in other ways. For example, the device implementation described above is only schematic. For example, the division of modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0321] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0322] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0323] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) or a processor (processor) to perform all or part of the steps of each implementation method of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program code.

[0324] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A fault detection method for an eddy current sensor, characterized in that: The method comprises: Sampling the first alternating current signal and the second alternating current signal output by the eddy current sensor to obtain sampling data; Based on the sampled data, determining whether the eddy current sensor has a target fault; Wherein, the target fault includes at least one of a DC fault and an AC fault; when the DC fault occurs in the eddy current sensor, at least one of the first AC signal and the second AC signal changes from an AC signal to a DC signal; when the AC fault occurs in the eddy current sensor, at least one of the first AC signal and the second AC signal changes to an abnormal AC signal.

2. The method according to claim 1, characterized in that The sampling data includes first sampling values ​​of the first AC signal and second sampling values ​​of the second AC signal corresponding to a plurality of first sampling moments respectively; and determining whether the eddy current sensor has a target fault based on the sampling data includes: Based on whether the first sampling value at each of the first sampling moments is within a first preset range, counting a first DC fault count corresponding to the first AC signal; and based on whether the second sampling value at each of the first sampling moments is within the first preset range, counting a second DC fault count corresponding to the second AC signal; Based on the first DC fault count and the second DC fault count, it is determined whether the DC fault exists.

3. The method according to claim 2, characterized in that The first DC fault count and the second DC fault count are obtained by counting when the absolute value of the rotation speed of the measured object is greater than the rotation speed threshold; and determining whether the DC fault exists based on the first DC fault count and the second DC fault count includes: In response to at least one of the first DC fault count and the second DC fault count satisfying a DC fault count condition, determining that the DC fault exists; In response to both the first DC fault count and the second DC fault count not satisfying the DC fault count condition, it is determined that the DC fault does not exist.

4. The method according to claim 2, characterized in that: The first DC fault count and the second DC fault count are obtained by counting when the absolute value of the rotation speed of the measured object is less than or equal to the rotation speed threshold; and determining whether the DC fault exists based on the first DC fault count and the second DC fault count includes: In response to both the first DC fault count and the second DC fault count satisfying a DC fault count condition, determining that the DC fault exists; In response to at least one of the first DC fault count and the second DC fault count not satisfying the DC fault count condition, it is determined that the DC fault does not exist.

5. The method according to claim 2, characterized in that: The counting of a first DC fault count corresponding to the first AC signal based on whether the first sampling value at each of the first sampling moments is within a first preset range, and the counting of a second DC fault count corresponding to the second AC signal based on whether the second sampling value at each of the first sampling moments is within the first preset range, include: For the first target sampling value at each of the first sampling moments, if the first target sampling value is within the first preset range, the first count value is added to the target DC fault count; if the first target sampling value is outside the first preset range, the second count value is subtracted from the target DC fault count; When the first target sampling value is the first sampling value, the target DC fault count is the first DC fault count; when the first target sampling value is the second sampling value, the target DC fault count is the second DC fault count.

6. The method according to claim 1, characterized in that The sampling data includes a third sampling value of the first AC signal and a fourth sampling value of the second AC signal corresponding to a plurality of second sampling moments respectively; and determining whether the eddy current sensor has a target fault based on the sampling data includes: Based on the third sampling value and the fourth sampling value at each of the second sampling moments, verification data corresponding to the first target signal at several verification moments are determined; wherein the verification data includes at least one of a square sum verification result, a DC offset verification result, a peak-to-peak value verification result and an orthogonality verification result, the square sum verification result is used to reflect whether the square sum of the first target signal and the second target signal meets the square sum verification condition, the DC offset verification result is used to reflect whether the DC offset of the first target signal meets the offset verification condition, the peak-to-peak value verification result is used to reflect whether the peak-to-peak value of the first target signal meets the peak-to-peak value verification condition, and the orthogonality verification result is used to reflect whether the first target signal and the second target signal meet the orthogonality verification condition; the first target signal is one of the first AC signal and the second AC signal, and the second target signal is the other of the first AC signal and the second AC signal; Based on whether the verification data at each verification time meets the requirements, counting the target AC fault count of the first target signal; Based on the target AC fault count, it is determined whether the eddy current sensor has the AC fault.

7. The method according to claim 6, characterized in that The verification time is the time when the extreme value of the first target signal is detected.

8. The method according to claim 7, characterized in that The step of detecting the extreme value of the first target signal comprises: Determine whether the current sampling value of the first target signal at the current sampling moment satisfies a preset boundary condition; wherein the current sampling moment is one of the plurality of second sampling moments, and the preset boundary condition includes: being greater than the latest updated prediction upper boundary or being less than the latest updated prediction lower boundary; If the current sampling value does not meet the preset boundary condition, the predicted upper boundary and the predicted lower boundary are kept unchanged, the second sampling moment next to the current sampling moment is used as the new current sampling moment, and the step of determining whether the current sampling value of the first target signal at the current sampling moment meets the preset boundary condition and subsequent steps are re-executed; If the current sampling value satisfies the preset boundary condition, the last updated first latch value is used as the newly updated second latch value, the last updated first prediction direction is used as the newly updated second prediction direction, the newly updated first prediction direction is determined based on the magnitude relationship between the current sampling value and the prediction boundary, the current sampling value is used as the newly updated first latch value, and the newly updated prediction upper boundary and the newly updated prediction lower boundary are determined based on the newly updated first latch value; Determining whether the newly updated first prediction direction is the same as the second prediction direction; If the newly updated first prediction direction is the same as the second prediction direction, taking the second sampling moment next to the current sampling moment as the new current sampling moment, and re-performing the step of determining whether the current sampling value of the first target signal at the current sampling moment satisfies the preset boundary condition and subsequent steps; If the newly updated first prediction direction is different from the newly updated second prediction direction, an extreme value of the first target signal is determined based on the newly updated first latch value and the newly updated second latch value.

9. The method according to claim 8, characterized in that The step of determining the extreme value of the first target signal based on the newly updated first latch value and the second latch value comprises: In response to the newly updated first prediction direction being a first direction and the newly updated second prediction direction being a second direction, determining a minimum value of the first target signal based on the newly updated first latch value and the newly updated second latch value; In response to the newly updated first prediction direction being the second direction and the newly updated second prediction direction being the first direction, determining a maximum value of the first target signal based on the newly updated first latch value and the newly updated second latch value; The first direction is used to indicate that the current sampling value is greater than the newly updated second latch value; the second direction is used to indicate that the current sampling value is less than the newly updated second latch value.

10. The method according to claim 9, characterized in that The target extreme value is a maximum value of the first target signal or a minimum value of the first target signal; and the step of determining the target extreme value based on the newly updated first latch value and the newly updated second latch value comprises: Using the newly updated first latch value as the target extreme value; or, Using the newly updated second latch value as the target extreme value; or, The newly updated integrated value of the first latch value and the second latch value is used as the target extreme value.

11. The method according to claim 8, characterized in that The determining the newly updated first prediction direction based on the magnitude relationship between the current sampling value and the prediction boundary includes: In response to the current sampling value being greater than the most recently updated prediction upper boundary, determining the newly updated first prediction direction as a first direction; In response to the current sampling value being smaller than the most recently updated prediction upper boundary, determining the newly updated first prediction direction as the second direction.

12. The method according to claim 8, characterized in that The determining the newly updated prediction upper boundary and the newly updated prediction lower boundary based on the newly updated first latch value comprises: Adding a first preset step length to the newly updated first latch value to obtain a newly updated prediction upper boundary; The newly updated first latch value is subtracted from the second preset step length to obtain the newly updated predicted lower boundary.

13. The method according to claim 7, characterized in that The verification data includes the square sum verification result, and the step of determining the square sum verification result of the first target signal at the verification time includes: Determine the sum of squares corresponding to a plurality of third sampling moments respectively; wherein the plurality of third sampling moments are a plurality of the second sampling moments between the last verification moment of the current verification moment and the current verification moment; In response to at least one of the square sums at the third sampling moments being outside a preset square sum range, determining that the square sum check result at the current check moment does not satisfy the square sum check condition; In response to the square sums at each of the third sampling moments being within the preset square sum range, it is determined that the square sum verification result at the current verification moment satisfies the square sum verification condition.

14. The method according to claim 7, characterized in that The verification data includes a target parameter verification result, and the step of determining the target parameter verification result of the first target signal at the verification time includes: Obtaining a first extreme value at a current verification moment and a second extreme value newly updated before the current verification moment; wherein the first extreme value is one of a maximum value and a minimum value, and the second extreme value is the other of the maximum value and the minimum value; Determining a target parameter based on the first extreme value and the second extreme value; In response to the target parameter being outside a second preset range, determining that the target parameter verification result at the current verification moment does not satisfy a target parameter verification condition; In response to the target parameter being within the second preset range, determining that the target parameter verification result at the current verification moment satisfies the target parameter verification condition; Among them, the target parameter, the second preset range, the target parameter verification result and the target parameter verification condition are respectively a DC offset, a preset offset range, the DC offset verification result and the offset verification condition, or the target parameter, the second preset range, the target parameter verification result and the target parameter verification condition are respectively a peak-to-peak value, a preset peak-to-peak value range, the peak-to-peak value verification result and the peak-to-peak value verification condition.

15. The method according to claim 7, characterized in that The verification data includes an orthogonality verification result, and the step of determining the orthogonality verification result of the first target signal at the verification time includes: Obtaining a second target sampling value of the second target signal at a current verification time; In response to the second target sampling value being outside a third preset range, determining that the orthogonality check result at the current check time does not satisfy the orthogonality check condition; In response to the second target sampling value being within the third preset range, it is determined that the orthogonality check result at the current check moment satisfies the orthogonality check condition.

16. The method according to claim 6, characterized in that The counting of the target AC fault count of the first target signal based on whether the verification data at each verification time meets the requirement includes: For each of the verification moments, if at least one of the verification results at the verification moment does not satisfy the corresponding verification conditions, the target AC fault count is added with a third count value; if all of the verification results at the verification moment satisfy the corresponding verification conditions, the target AC fault count is subtracted with a fourth count value.

17. The method according to claim 1, characterized in that After determining that the target fault exists, the method further includes: Perform a software reset to re-execute fault detection; Add the current reset times to the preset times; Determine whether the current reset number is greater than or equal to a reset number threshold; If the current reset number is less than the reset number threshold, determine whether the target fault is detected again within the preset time window; if the target fault is detected again within the preset time window, re-execute the software reset operation and its subsequent steps; if the target fault is not detected again within the preset time window, subtract the preset number from the current reset number, and re-execute the determination of whether the target fault is detected again within the preset time window and its subsequent steps; If the current number of resets is greater than or equal to the reset number threshold, a fault protection instruction is generated, and the fault protection instruction is used to instruct the object under test to stop running.

18. A fault detection device for an eddy current sensor, characterized in that: The device comprises: An acquisition module, used for sampling the first AC signal and the second AC signal output by the eddy current sensor to obtain sampled data; A fault detection module, used for determining whether the eddy current sensor has a target fault based on the sampled data; Wherein, the target fault includes at least one of a DC fault and an AC fault; when the DC fault occurs in the eddy current sensor, at least one of the first AC signal and the second AC signal changes from an AC signal to a DC signal; when the AC fault occurs in the eddy current sensor, at least one of the first AC signal and the second AC signal changes to an abnormal AC signal.

19. An electronic device, characterized in that: comprising a memory and a processor coupled to each other, The memory stores program instructions; The processor is used to execute program instructions stored in the memory to implement the method according to any one of claims 1 to 17.

20. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store program instructions, and the program instructions can be executed by a processor to implement the method according to any one of claims 1 to 17.

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