Sensor fault detection system and method, motor controller and vehicle

Abstract

The invention relates to a sensor fault detection system and method, a motor controller and a vehicle, and relates to the technical field of fault detection. The sensor fault detection system comprises a first signal conversion circuit, a second signal conversion circuit and a processor. Wherein the first signal conversion circuit performs amplitude modulation on an original differential signal output by a sensor to obtain an amplitude-modulated differential signal; a second signal conversion circuit converts the original differential signal to obtain a single-ended signal; and the processor is connected with the first signal conversion circuit and the second signal conversion circuit, and obtains a fault detection result according to the amplitude modulation differential signal and the single-ended signal. An original differential signal output by a sensor is subjected to amplitude modulation processing through a first signal conversion circuit, and meanwhile, the original differential signal is converted into a single-ended signal through a second signal conversion circuit. Thus, through two different forms of signals, namely the amplitude modulation differential signal and the single-ended signal, the processor can capture more fault features, and the accuracy of sensor fault detection is improved.

Description

Technical Field

[0001] The present application relates to the technical field of fault detection, and in particular to a sensor fault detection system, method, motor controller and vehicle. Background Art

[0002] With the development of automated control, such as in the field of vehicle manufacturing, sensors, as key data acquisition and conversion components, their stability and reliability are crucial to the overall performance of the system. Therefore, it is necessary to perform fault detection on the sensors so that appropriate measures can be taken in time when a sensor fails.

[0003] Since the working environment of sensors is complex and changeable, there are many potential interference sources, such as electromagnetic interference, temperature changes, mechanical vibration, etc., which will not only have an adverse effect on the normal operation of sensors, but also increase the difficulty of sensor fault detection. Therefore, how to improve the accuracy of sensor fault detection is an urgent problem to be solved. Summary of the invention

[0004] The embodiments of the present application provide a sensor fault detection system, method, motor controller and vehicle to improve the accuracy of sensor fault detection, so as to at least partially solve the above-mentioned technical problems.

[0005] In order to achieve the above object, according to a first aspect of the present application, a sensor fault detection system is provided, comprising:

[0006] The first signal conversion circuit performs amplitude modulation on the original differential signal output by the sensor to obtain an amplitude modulated differential signal;

[0007] A second signal conversion circuit converts the original differential signal to obtain a single-ended signal;

[0008] A processor is connected to the first signal conversion circuit and the second signal conversion circuit, and is used to obtain a fault detection result according to the amplitude modulated differential signal and the single-ended signal.

[0009] Optionally, the first signal conversion circuit includes a proportional operational amplifier;

[0010] The proportional operational amplifier includes an input terminal connected to the original differential signal and an output terminal outputting the amplitude modulated differential signal.

[0011] Optionally, the second signal conversion circuit includes a pull-up subcircuit, a bias subcircuit and a differential operational amplifier;

[0012] The pull-up subcircuit is connected to the sensor, and pulls up the original differential signal to obtain a pull-up differential signal; wherein the pull-up differential signal includes a first pull-up signal and a second pull-up signal;

[0013] The bias subcircuit is used to provide a bias voltage;

[0014] The differential operational amplifier includes a first input terminal connected to the pull-up subcircuit to receive the first pull-up signal, a second input terminal connected to the pull-up subcircuit and the bias subcircuit to receive the second pull-up signal and the bias voltage, and an output terminal connected to the processor.

[0015] Optionally, the pull-up subcircuit includes a first resistor and a second resistor;

[0016] The first resistor includes a first end connected to the sensor and the first input of the differential operational amplifier and a second end connected to the first end of the second resistor and a pull-up voltage source;

[0017] The second resistor also includes a second terminal connected to the sensor, the second input terminal of the differential operational amplifier, and the bias subcircuit.

[0018] Optionally, the bias subcircuit includes a third resistor and a first capacitor;

[0019] The third resistor includes a first end connected to the pull-up sub-circuit and the differential operational amplifier and a second end connected to a bias voltage source;

[0020] The first capacitor is arranged in parallel between the first end and the second end of the third resistor.

[0021] Optionally, the bias subcircuit further includes a fourth resistor and a second capacitor;

[0022] The fourth resistor includes a first end connected to the first input end of the differential operational amplifier and a second end connected to the output end of the differential operational amplifier;

[0023] The second capacitor is arranged in parallel between the first end and the second end of the fourth resistor.

[0024] Optionally, the second signal conversion circuit further includes a filtering subcircuit;

[0025] The filtering subcircuit is arranged between the sensor and the pull-up subcircuit, and is used for filtering the original differential signal and then outputting the filtered signal to the pull-up subcircuit.

[0026] Optionally, the filtering subcircuit includes a third capacitor, a fourth capacitor and a common-mode inductor;

[0027] The common mode inductor comprises a first input terminal connected to the third capacitor and the sensor, a first output terminal connected to the pull-up sub-circuit, a second input terminal connected to the fourth capacitor and the sensor, and a second output terminal connected to the pull-up sub-circuit;

[0028] The third capacitor comprises a first end connected to the first input end of the common mode inductor and a second end connected to the first end of the fourth capacitor and the ground;

[0029] The fourth capacitor further includes a second terminal connected to the second input terminal of the common mode inductor.

[0030] Optionally, the processor includes a first core, a second core and an analysis unit;

[0031] The first core is connected to the first signal conversion circuit and generates a first detection result according to the amplitude modulated differential signal;

[0032] The second core is connected to the second signal conversion circuit and generates a second detection result according to the single-ended signal;

[0033] The analysis unit is connected to the first core and the second core, and is used to generate the fault detection result when the first detection result is consistent with the second detection result.

[0034] According to a second aspect of the present application, a sensor fault detection method is provided, which is implemented based on the above-mentioned sensor fault detection system, and the method includes:

[0035] Creating a fault mapping table based on the amplitude modulated differential signal and the single-ended signal under each fault type of the sensor;

[0036] The fault detection result is determined from the fault mapping table based on the amplitude modulated differential signal output by the first signal conversion circuit in real time and the single-ended signal output by the second signal conversion circuit in real time.

[0037] Optionally, the fault mapping table includes a first mapping table and a second mapping table; and the creating the fault mapping table based on the amplitude modulated differential signal and the single-ended signal under each fault type of the sensor includes:

[0038] Analyze the first characteristic value of the amplitude modulated differential signal and the second characteristic value of the single-ended signal under each fault type of the sensor;

[0039] Creating the first mapping table based on the first characteristic value under each fault type;

[0040] Creating the second mapping table based on the second characteristic value under each fault type;

[0041] The first mapping table includes the corresponding relationship between the first characteristic value and the fault type under each fault type; the second mapping table includes the corresponding relationship between the second characteristic value and the fault type under each fault type.

[0042] Optionally, determining the fault detection result from the fault mapping table based on the amplitude modulated differential signal output by the first signal conversion circuit in real time and the single-ended signal output by the second signal conversion circuit in real time includes:

[0043] Analyze the third characteristic value of the amplitude modulated differential signal output by the first signal conversion circuit in real time and the fourth characteristic value of the single-ended signal output by the second signal conversion circuit in real time;

[0044] Based on the third characteristic value, determining a first fault type from the first mapping table;

[0045] Based on the fourth characteristic value, determining a second fault type from the second mapping table;

[0046] When the first fault type and the second fault type are consistent, the fault detection result is generated.

[0047] Optionally, the first eigenvalue, the second eigenvalue, the third eigenvalue, and the fourth eigenvalue include at least two of a maximum value, a minimum value, a reference value, and an amplitude.

[0048] Optionally, the fault types include one or more combinations of open circuit / short circuit of power line, open circuit / short circuit of ground line, open circuit / short circuit of positive sine line, open circuit / short circuit of negative sine line, open circuit / short circuit of positive cosine line, open circuit / short circuit of negative cosine line, open circuit / short circuit between positive sine line and negative sine line, open circuit / short circuit between positive cosine line and negative cosine line, open circuit / short circuit between positive sine line and positive cosine line, open circuit / short circuit between positive sine line and negative cosine line, open circuit / short circuit between negative sine line and positive cosine line, open circuit / short circuit between negative sine line and positive cosine line, open circuit / short circuit between positive sine line and ground, open circuit / short circuit between negative sine line and ground, open circuit / short circuit between positive cosine line and ground, and open circuit / short circuit between negative cosine line and ground.

[0049] According to a third aspect of the present application, a motor controller is provided, comprising:

[0050] Memory;

[0051] processor;

[0052] The processor has stored thereon a computer program executed by the motor controller;

[0053] When the computer program is executed by the processor, the processor executes the sensor fault detection method as described above.

[0054] According to a fourth aspect of the present application, a vehicle is provided, comprising the sensor fault detection system as described above, or comprising the motor controller as described above.

[0055] In the sensor fault detection system of the embodiment of the present application, first, the original differential signal output by the sensor is amplitude modulated by the first signal conversion circuit to improve the stability of the original differential signal. At the same time, the second signal conversion circuit converts the original differential signal into a single-ended signal, which not only simplifies the complexity of subsequent processing, but also retains the effective information of the original signal through different signal forms. Finally, by using two different forms of signals, the amplitude modulated differential signal and the single-ended signal, the processor can capture more fault features, thereby improving the accuracy of sensor fault detection.

[0056] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0058] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same figure numbers represent the same parts in the following description.

[0059] Figure 1 is a block diagram of a sensor fault detection system provided in an exemplary embodiment of the present disclosure;

[0060] Figure 2 is a signal connection diagram of a sensor fault detection system provided in an exemplary embodiment of the present disclosure;

[0061] Figure 3 is a circuit connection diagram of a sensor fault detection system provided in an exemplary embodiment of the present disclosure;

[0062] Figure 4 is a flow chart of a sensor fault detection method provided in an exemplary embodiment of the present disclosure;

[0063] Figure 5 is a flowchart of a method for creating a fault mapping table provided in an exemplary embodiment of the present disclosure;

[0064] Figure 6 is a flow chart of a method for outputting a fault detection result provided in an exemplary embodiment of the present disclosure.

[0065] Explanation of the reference numerals: 1. first signal conversion circuit; 2. second signal conversion circuit; 21. pull-up sub-circuit; 22. bias sub-circuit; 23. filter sub-circuit; 3. processor; 31. first core; 32. second core; 33. analysis unit. DETAILED DESCRIPTION

[0066] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0067] According to the first aspect of the present application, referring to Figures 1 to 3 The present disclosure provides a sensor fault detection system, including a first signal conversion circuit 1, a second signal conversion circuit 2 and a processor 3; wherein the first signal conversion circuit 1 modulates the original differential signal output by the sensor to obtain an amplitude modulated differential signal; the second signal conversion circuit 2 converts the original differential signal to obtain a single-ended signal; the processor 3 is connected to the first signal conversion circuit 1 and the second signal conversion circuit 2, and obtains a fault detection result according to the amplitude modulated differential signal and the single-ended signal.

[0068] The sensor may be a position sensor, an eddy current sensor, a rotary transformer sensor, a linear Hall sensor or other sensor that outputs sine and cosine signals.

[0069] As an example, combining Figure 2 The original differential signal may include an original cosine differential signal and / or an original sine differential signal, the original cosine differential signal includes an original positive cosine signal and an original negative cosine signal with a phase difference of 180 degrees, and the original sine differential signal includes an original positive sine signal and an original negative sine signal with a phase difference of 180 degrees, Figure 2Where sin+ represents the original positive sine signal, sin- represents the original negative sine signal, cos+ represents the original positive cosine signal, and cos- represents the original negative cosine signal. The first signal conversion circuit modulates the original cosine differential signal and / or the original sine differential signal to generate an amplitude modulated differential signal. The amplitude modulated differential signal corresponds to the original differential signal one by one. The amplitude modulated differential signal may include an amplitude modulated positive cosine signal cos1+, an amplitude modulated negative cosine signal cos1-, an amplitude modulated positive sine signal sin1+, and an amplitude modulated negative sine signal sin1-. The second signal conversion circuit 2 converts the original differential signal to obtain a single-ended signal. The single-ended signal may include a single-ended sine signal SINOUT and a single-ended cosine signal COSOUT, that is, converting the original cosine differential signal into a single-ended cosine signal COSOUT, and converting the original sine differential signal into a single-ended sine signal SINOUT.

[0070] In the above implementation, first, the original differential signal output by the sensor is amplitude modulated by the first signal conversion circuit 1 to improve the stability of the original differential signal. At the same time, the second signal conversion circuit 2 converts the original differential signal into a single-ended signal, which not only simplifies the complexity of subsequent processing, but also retains the effective information of the original signal through different signal forms. Finally, by using two different forms of signals, the amplitude modulated differential signal and the single-ended signal, the processor 3 can capture more fault features, thereby improving the accuracy of sensor fault detection.

[0071] In some embodiments, the first signal conversion circuit 1 includes a proportional operational amplifier; the proportional operational amplifier includes an input terminal connected to the original differential signal and an output terminal outputting the amplitude modulated differential signal.

[0072] As an example, the proportional operational amplifier may include a plurality of input terminals and a plurality of output terminals corresponding one-to-one to the input terminals, so as to process the multiple original differential signals respectively.

[0073] Reference Figure 3 In some embodiments, the second signal conversion circuit 2 includes a pull-up subcircuit 21, a bias subcircuit 22 and a differential operational amplifier U1; the pull-up subcircuit 21 is connected to the sensor to pull up the original differential signal to obtain a pull-up differential signal; wherein the pull-up differential signal includes a first pull-up signal and a second pull-up signal; the bias subcircuit 22 is used to provide a bias voltage; the differential operational amplifier U1 includes a first input terminal connected to the pull-up subcircuit 21 to receive the first pull-up signal, a second input terminal connected to the pull-up subcircuit 21 and the bias subcircuit 22 to receive the second pull-up signal and the bias voltage, and an output terminal connected to the processor 3.

[0074] In the above implementation, first, the pull-up subcircuit 21 performs pull-up processing on the original differential signal to generate a first pull-up signal and a second pull-up signal, thereby enhancing the stability of the signal. Then, the bias subcircuit 22 provides a bias voltage, and the bias voltage and the second pull-up signal act together on the second input terminal of the differential operational amplifier U1, providing a reference level for the differential operational amplifier U1, so as to adjust the gain of the differential operational amplifier U1. Finally, the first input terminal of the differential operational amplifier U1 is used to receive the first pull-up signal, and the second input terminal simultaneously receives the second pull-up signal after bias adjustment, and outputs it from the output terminal of the differential operational amplifier U1 in the form of a single-ended signal, thereby realizing the conversion of the original differential signal to the single-ended signal, and the adjustment of the amplitude of the single-ended signal is also realized through the pull-up subcircuit 21 and the bias subcircuit 22.

[0075] Reference Figure 3 In some embodiments, the pull-up subcircuit 21 includes a first resistor R1 and a second resistor R2; the first resistor R1 includes a first end connected to the sensor and the first input end of the differential operational amplifier U1 and a second end connected to the first end of the second resistor R2 and the pull-up voltage source; the second resistor R2 also includes a second end connected to the sensor, the second input end of the differential operational amplifier U1 and the bias subcircuit 22.

[0076] Reference Figure 3 In some embodiments, the bias sub-circuit 22 includes a third resistor R3 and a first capacitor C1; the third resistor R3 includes a first end connected to the pull-up sub-circuit 21 and the differential operational amplifier U1 and a second end connected to the bias voltage source; the first capacitor C1 is arranged in parallel between the first end and the second end of the third resistor R3.

[0077] As an example, Figure 3 V1 in the figure represents the pull-up voltage output by the pull-up voltage source, and V2 represents the bias voltage output by the bias voltage source. The pull-up voltage and the bias voltage can be set according to the rated voltage of the processor 3. For example, when the rated voltage N of the processor 3 is greater than the preset value, the pull-up voltage V1 and the bias voltage V2 can be set to be equal to the rated voltage of the processor 3; when the rated voltage N of the processor 3 is less than the preset value, the pull-up voltage V1 and the bias voltage V2 can be set to half of the rated voltage of the processor 3. For example, the preset value can be 4V. If a processor 3 with a rated voltage of 3.3V is used, its voltage sampling range is 0-3.3V. At this time, the rated voltage of the processor 3 is less than 4V, then the pull-up voltage V1 and the bias voltage V2 are both set to 1.65V. In this way, the amplitude of the pull-up voltage V1 and the bias voltage V2 can be set according to the rated voltage of the processor 3, so as to keep the differential operational amplifier U1 in a suitable working range.

[0078] In some embodiments, the bias subcircuit 22 also includes a fourth resistor R4 and a second capacitor C2; the fourth resistor R4 includes a first end connected to the first input end of the differential operational amplifier U1 and a second end connected to the output end of the differential operational amplifier U1; the second capacitor C2 is arranged in parallel between the first end and the second end of the fourth resistor R4.

[0079] In the above implementation, the fourth resistor R4 forms a negative feedback loop to stabilize the working state of the differential operational amplifier U1 and reduce the output fluctuation of the differential operational amplifier U1. And by adjusting the resistance value of the fourth resistor R4, the feedback strength can be controlled to optimize the gain stability and linearity of the differential operational amplifier U1.

[0080] The second capacitor C2 is connected in parallel at both ends of the fourth resistor R4 to form a low-pass filter to filter out interference signals, thereby improving the working stability of the differential operational amplifier U1.

[0081] As an example, a fifth capacitor C5, a sixth capacitor C6 and a seventh capacitor C7 may also be included between the differential operational amplifier U1 and the pull-up sub-circuit 21, wherein the fifth capacitor C5 and the sixth capacitor C6 are connected in series and then arranged in parallel between the first input terminal and the second input terminal of the differential operational amplifier U1, and the series connection point of the fifth capacitor C5 and the sixth capacitor C6 is grounded to form a Y capacitor structure to suppress common mode interference. The seventh capacitor C7 is arranged in parallel between the first input terminal and the second input terminal of the differential operational amplifier U1 to form an X capacitor structure to filter out differential mode interference.

[0082] As an example, a bidirectional switch diode D1 is further provided at the output end of the differential operational amplifier U1 , and the bidirectional switch diode D1 clamps the single-ended signal output by the differential operational amplifier U1 .

[0083] In some embodiments, the second signal conversion circuit 2 further includes a filtering subcircuit 23 ; the filtering subcircuit 23 is disposed between the sensor and the pull-up subcircuit 21 , and is used for filtering the original differential signal and outputting the filtered signal to the pull-up subcircuit 21 .

[0084] As an example, the filtering subcircuit 23 includes a third capacitor C3, a fourth capacitor C4 and a common-mode inductor T1; the common-mode inductor T1 includes a first input terminal connected to the third capacitor C3 and the sensor, a first output terminal connected to the pull-up subcircuit 21, a second input terminal connected to the fourth capacitor C4 and the sensor, and a second output terminal connected to the pull-up subcircuit 21; the third capacitor C3 includes a first terminal connected to the first input terminal of the common-mode inductor T1 and a second terminal connected to the first terminal of the fourth capacitor C4 and the ground; the fourth capacitor C4 also includes a second terminal connected to the second input terminal of the common-mode inductor T1.

[0085] As an example, the filtering subcircuit 23 further includes a fifth resistor R5 and a sixth resistor R6, wherein both ends of the fifth resistor R5 are respectively connected to the first input end and the first output end of the common mode inductor T1, and both ends of the sixth inductor are respectively connected to the second input end and the second output end of the common mode inductor T1.

[0086] In the above implementation, the filter subcircuit 23 adopts a symmetrical structure to filter out the common-mode and differential-mode interference in the original differential current signal. The common-mode inductor T1 reduces the common-mode noise through the mutual cancellation mechanism of the magnetic field inside it, and the third capacitor C3 and the fourth capacitor C4 are filter capacitors, which are respectively connected in parallel between the two input terminals of the common-mode inductor T1 and the ground, forming two low-pass filter paths to filter out the differential-mode noise.

[0087] In some embodiments, the processor 3 includes a first core 31, a second core 32 and an analysis unit 33; the first core 31 is connected to the first signal conversion circuit 1, and generates a first detection result according to the amplitude modulated differential signal; the second core 32 is connected to the second signal conversion circuit 2, and generates a second detection result according to the single-ended signal; the analysis unit 33 is connected to the first core 31 and the second core 32, and is used to generate a fault detection result when the first detection result and the second detection result are consistent.

[0088] As an example, the first core 31 and the second core 32 may be the same core in the processor 3 , or may be different cores in the processor 3 , which is not specifically limited here.

[0089] As an example, when the first detection result and the second detection result are consistent, a fault detection result is generated. When the first detection result and the second detection result are inconsistent, the original differential signal is converted again by the first signal conversion circuit 1 and the second signal conversion circuit 2 to regenerate the first detection result and the second detection result.

[0090] Reference Figure 4 According to the second aspect of the present application, a sensor fault detection method is provided, which is implemented based on the above-mentioned sensor fault detection system. The method includes steps S101-S102, which are described in detail below.

[0091] Step S101: creating a fault mapping table based on the amplitude modulated differential signal and the single-ended signal under each fault type of the sensor;

[0092] The fault mapping table includes a first mapping table and a second mapping table.

[0093] Step S102: determining the fault detection result from the fault mapping table based on the amplitude modulated differential signal output by the first signal conversion circuit 1 in real time and the single-ended signal output by the second signal conversion circuit 2 in real time.

[0094] In the above implementation, by pre-analyzing and recording the characteristics of the amplitude modulated differential signal and the single-ended signal of the sensor under different fault types, a fault mapping table is constructed to record the signal change patterns under various fault types of the sensor. When the sensor is in real-time operation, the first signal conversion circuit 1 outputs the amplitude modulated differential signal in real time, and the second signal conversion circuit 2 outputs the single-ended signal in real time. By comparing and matching these two real-time signals with the data in the fault mapping table, the current sensor state can be quickly and accurately identified, including whether a fault occurs and the specific fault type.

[0095] Reference Figure 5 In some embodiments, step S101 may include steps S1011 to S1013, which are described in detail below.

[0096] Step S1011: analyzing the first characteristic value of the amplitude modulated differential signal and the second characteristic value of the single-ended signal under various fault types of the sensor;

[0097] Step S1012: creating a first mapping table based on the first characteristic value of each fault type;

[0098] Step S1013: creating a second mapping table based on the second characteristic value of each fault type;

[0099] The first eigenvalue, the second eigenvalue, the third eigenvalue, and the fourth eigenvalue include at least two of a maximum value, a minimum value, a reference value, and an amplitude. The fault types include one or more combinations of open circuit / short circuit of the power line, open circuit / short circuit of the ground line, open circuit / short circuit of the positive sine line, open circuit / short circuit of the negative sine line, open circuit / short circuit of the positive cosine line, open circuit / short circuit of the negative cosine line, open circuit / short circuit between the positive sine line and the negative sine line, open circuit / short circuit between the positive cosine line and the negative cosine line, open circuit / short circuit between the positive sine line and the positive cosine line, open circuit / short circuit between the positive sine line and the negative cosine line, open circuit / short circuit between the negative sine line and the positive cosine line, open circuit / short circuit between the negative sine line and the positive cosine line, open circuit / short circuit between the positive sine line and the ground, open circuit / short circuit between the negative sine line and the ground, open circuit / short circuit between the positive cosine line and the ground, and open circuit / short circuit between the negative cosine line and the ground.

[0100] The first mapping table includes the correspondence between the first characteristic value and the fault type under each fault type; the second mapping table includes the correspondence between the second characteristic value and the fault type under each fault type. As an example, Table 1 is an example of the second mapping table, wherein the single-ended signal includes a single-ended sine signal SINOUT and a single-ended cosine signal COSOUT, and the second characteristic value includes a SINOUT maximum value, a SINOUT minimum value, a SINOUT reference value, a SINOUT amplitude, a COSOUT maximum value, a COSOUT minimum value, a COSOUT reference value, and a COSOUT amplitude. "XX" in Table 1 represents the second characteristic value under each fault type, which can be measured by experiment.

[0101] Table 1

[0102]

[0103] As an example, taking the sample data in Table 1 as an example, the minimum value of the second characteristic value when the sensor is operating normally is 0.13V, the maximum value is 2.89V, the reference value is 1.51V, and the amplitude is 2.76V; when the sensor has a power line open circuit fault, the minimum value of the second characteristic value becomes 1.43V, the maximum value becomes 1.57V, the reference value becomes 1.5V, and the amplitude becomes 0.14V. When the processor 3 reads the first characteristic value of this group, it is determined that the sensor has a power line disconnection fault.

[0104] Reference Figure 6 In some embodiments, step S102 may include steps S1021 to S1024, which are described in detail below.

[0105] Step S1021: analyzing the third characteristic value of the amplitude modulated differential signal output by the first signal conversion circuit 1 in real time and the fourth characteristic value of the single-ended signal output by the second signal conversion circuit 2 in real time;

[0106] Step S1022: determining a first fault type from the first mapping table based on the third characteristic value;

[0107] Step S1023: determining a second fault type from the second mapping table based on the fourth characteristic value;

[0108] Step S1024: When the first fault type and the second fault type are consistent, generating the fault detection result.

[0109] In the above implementation, the third characteristic value of the amplitude modulated differential signal output in real time by the first signal conversion circuit 1 and the fourth characteristic value of the single-ended signal output in real time by the second signal conversion circuit 2 are first extracted to reflect the output of the current sensor. Based on the third characteristic value and the fourth characteristic value, the corresponding fault type is searched from the pre-constructed first mapping table and the second mapping table, respectively. When the first fault type determined by the third characteristic value of the amplitude modulated differential signal is consistent with the second fault type determined by the fourth characteristic value of the single-ended signal, the fault detection result is finally generated, and the reliability of the sensor fault detection is greatly improved by the double confirmation method. Even if one of the signal paths is affected by interference or error, the verification of the other signal path can effectively avoid misjudgment.

[0110] According to a third aspect of the present application, there is provided a motor controller, comprising: a memory and a processor;

[0111] The processor stores a computer program to be executed by the motor controller; when the computer program is executed by the processor, the processor executes the sensor fault detection method as described above.

[0112] According to a fourth aspect of the present application, a vehicle is provided, comprising the sensor fault detection system as described above, or comprising the motor controller as described above.

[0113] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0114] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0115] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0116] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A sensor fault detection system, characterized in that: include: The first signal conversion circuit performs amplitude modulation on the original differential signal output by the sensor to obtain an amplitude modulated differential signal; A second signal conversion circuit converts the original differential signal to obtain a single-ended signal; A processor is connected to the first signal conversion circuit and the second signal conversion circuit, and is used to obtain a fault detection result according to the amplitude modulated differential signal and the single-ended signal.

2. The sensor fault detection system according to claim 1, characterized in that: The first signal conversion circuit includes a proportional operational amplifier; The proportional operational amplifier comprises an input terminal connected to the original differential signal and an output terminal outputting the amplitude modulated differential signal.

3. The sensor fault detection system according to claim 1, characterized in that: The second signal conversion circuit includes a pull-up subcircuit, a bias subcircuit and a differential operational amplifier; The pull-up subcircuit is connected to the sensor, and pulls up the original differential signal to obtain a pull-up differential signal; wherein the pull-up differential signal includes a first pull-up signal and a second pull-up signal; The bias subcircuit is used to provide a bias voltage; The differential operational amplifier includes a first input terminal connected to the pull-up subcircuit to receive the first pull-up signal, a second input terminal connected to the pull-up subcircuit and the bias subcircuit to receive the second pull-up signal and the bias voltage, and an output terminal connected to the processor.

4. The sensor fault detection system according to claim 3, characterized in that: The pull-up subcircuit includes a first resistor and a second resistor; The first resistor includes a first end connected to the sensor and the first input of the differential operational amplifier and a second end connected to the first end of the second resistor and a pull-up voltage source; The second resistor also includes a second terminal connected to the sensor, the second input terminal of the differential operational amplifier, and the bias subcircuit.

5. The sensor fault detection system according to claim 3, characterized in that: The bias subcircuit includes a third resistor and a first capacitor; The third resistor includes a first end connected to the pull-up sub-circuit and the differential operational amplifier and a second end connected to a bias voltage source; The first capacitor is arranged in parallel between the first end and the second end of the third resistor.

6. The sensor fault detection system according to claim 5, characterized in that: The bias subcircuit also includes a fourth resistor and a second capacitor; The fourth resistor includes a first end connected to the first input end of the differential operational amplifier and a second end connected to the output end of the differential operational amplifier; The second capacitor is arranged in parallel between the first end and the second end of the fourth resistor.

7. The sensor fault detection system according to claim 3, characterized in that: The second signal conversion circuit also includes a filtering subcircuit; The filtering subcircuit is arranged between the sensor and the pull-up subcircuit, and is used for filtering the original differential signal and then outputting the filtered signal to the pull-up subcircuit.

8. The sensor fault detection system according to claim 7, characterized in that: The filtering subcircuit includes a third capacitor, a fourth capacitor and a common mode inductor; The common mode inductor comprises a first input terminal connected to the third capacitor and the sensor, a first output terminal connected to the pull-up sub-circuit, a second input terminal connected to the fourth capacitor and the sensor, and a second output terminal connected to the pull-up sub-circuit; The third capacitor comprises a first end connected to the first input end of the common mode inductor and a second end connected to the first end of the fourth capacitor and the ground; The fourth capacitor further includes a second terminal connected to the second input terminal of the common mode inductor.

9. The sensor fault detection system according to any one of claims 1 to 8, characterized in that: The processor includes a first core, a second core and an analysis unit; The first core is connected to the first signal conversion circuit and generates a first detection result according to the amplitude modulated differential signal; The second core is connected to the second signal conversion circuit and generates a second detection result according to the single-ended signal; The analysis unit is connected to the first core and the second core, and is used to generate the fault detection result when the first detection result is consistent with the second detection result.

10. A sensor fault detection method, implemented based on the sensor fault detection system according to any one of claims 1 to 9, characterized in that: The method comprises: Creating a fault mapping table based on the amplitude modulated differential signal and the single-ended signal under each fault type of the sensor; The fault detection result is determined from the fault mapping table based on the amplitude modulated differential signal output by the first signal conversion circuit in real time and the single-ended signal output by the second signal conversion circuit in real time.

11. The sensor fault detection method according to claim 10, characterized in that: The fault mapping table includes a first mapping table and a second mapping table; the fault mapping table is created based on the amplitude modulated differential signal and the single-ended signal under each fault type of the sensor, including: Analyze the first characteristic value of the amplitude modulated differential signal and the second characteristic value of the single-ended signal under each fault type of the sensor; Creating the first mapping table based on the first characteristic value under each fault type; Creating the second mapping table based on the second characteristic value under each fault type; The first mapping table includes the corresponding relationship between the first characteristic value and the fault type under each fault type; the second mapping table includes the corresponding relationship between the second characteristic value and the fault type under each fault type.

12. The sensor fault detection method according to claim 11, characterized in that: include: The determining the fault detection result from the fault mapping table based on the amplitude modulated differential signal output by the first signal conversion circuit in real time and the single-ended signal output by the second signal conversion circuit in real time includes: Analyze the third characteristic value of the amplitude modulated differential signal output by the first signal conversion circuit in real time and the fourth characteristic value of the single-ended signal output by the second signal conversion circuit in real time; Based on the third characteristic value, determining a first fault type from the first mapping table; Based on the fourth characteristic value, determining a second fault type from the second mapping table; When the first fault type and the second fault type are consistent, the fault detection result is generated.

13. The sensor fault detection method according to any one of claims 11 to 12, characterized in that: The first eigenvalue, the second eigenvalue, the third eigenvalue, and the fourth eigenvalue include at least two of a maximum value, a minimum value, a reference value, and an amplitude.

14. The sensor fault detection method according to any one of claims 11 to 12, characterized in that: The fault types include one or more combinations of open circuit / short circuit of power line, open circuit / short circuit of ground line, open circuit / short circuit of positive sine line, open circuit / short circuit of negative sine line, open circuit / short circuit of positive cosine line, open circuit / short circuit of negative cosine line, open circuit / short circuit between positive sine line and negative sine line, open circuit / short circuit between positive cosine line and negative cosine line, open circuit / short circuit between positive sine line and positive cosine line, open circuit / short circuit between positive sine line and negative cosine line, open circuit / short circuit between negative sine line and positive cosine line, open circuit / short circuit between negative sine line and negative cosine line, open circuit / short circuit between positive sine line and ground, open circuit / short circuit between negative sine line and ground, open circuit / short circuit between positive cosine line and ground, and open circuit / short circuit between negative cosine line and ground.

15. A motor controller, characterized in that: include: Memory; processor; The processor has stored thereon a computer program executed by the motor controller; When the computer program is executed by the processor, the processor is caused to perform the sensor fault detection method according to any one of claims 10 to 14.

16. A vehicle, characterized in that: Includes the sensor fault detection system as described in any one of claims 1 to 9, or includes the motor controller as described in claim 15.

Images