Magnetoresistive sensor acquisition system and detection method

Abstract

The invention relates to the field of industrial control, in particular to a magnetoresistive sensor acquisition system and a detection method.The acquisition system is used for measuring the rotating speed of a gear in the industrial control field where the rotating speed needs to be acquired and comprises a terminal board, a first resistor, a first acquisition card, a second acquisition card, a bottom board and an upper computer; the first resistor is electrically connected with the terminal plate, the terminal plate is electrically connected with the bottom plate, and the first acquisition card and the second acquisition card are fixed on the bottom plate through slots of the bottom plate and are electrically connected with the bottom plate respectively; the first acquisition card is electrically connected with the second acquisition card through a serial port; the upper computer is electrically connected with the first acquisition card and the second acquisition card; the first acquisition card and the second acquisition card are the same acquisition card. The technical problems that in the prior art, when the magnetoresistive sensor is detected, external faults cannot be comprehensively detected, and the accuracy is low are solved.

Description

Technical Field

[0001] The present invention relates to the field of industrial control, and in particular to a magnetoresistive sensor acquisition system and a detection method. Background Art

[0002] At present, magnetoresistive sensors are widely used in gear speed measurement systems. When the gear rotates, the magnetoresistive sensor will induce an AC voltage signal, and the frequency and amplitude of the signal are proportional to the gear speed.

[0003] In the field of industrial control where rotation speed needs to be collected, such as in power generation systems such as DEH systems and gas turbine control systems, the system cannot be shut down easily. If it is shut down, it will cause losses to customers. Therefore, in order to ensure the stability and reliability of the speed measurement module, it is necessary to effectively detect the connection status of the magnetic sensor to prevent the adverse effects caused by disconnection, short circuit, aging and other problems of the magnetic resistance sensor.

[0004] The magnetoresistive sensor fault detection in the prior art only has a disconnection detection function and cannot cover all fault conditions of the magnetoresistive sensor. At the same time, the accuracy of the magnetoresistive sensor fault detection in the prior art is low.

[0005] Therefore, there is an urgent need for a magnetoresistive sensor acquisition system and detection method that can cover all external faults and has high accuracy. Summary of the invention

[0006] 1. Technical issues to be resolved

[0007] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a magnetoresistive sensor acquisition system and detection method, which solves the technical problems in the prior art that when detecting magnetoresistive sensors, external faults cannot be fully detected and the accuracy is low.

[0008] (II) Technical solution

[0009] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0010] In a first aspect, an embodiment of the present invention provides a magnetoresistive sensor acquisition system for detecting a magnetoresistive sensor in gear speed measurement in an industrial control field where speed acquisition is required. The acquisition system includes:

[0011] Terminal board, first resistor, first acquisition card, second acquisition card, bottom board and host computer;

[0012] The first resistor is electrically connected to the terminal board, the terminal board is electrically connected to the bottom board, the first acquisition card and the second acquisition card are fixed on the bottom board through the slots of the bottom board, and are electrically connected to the bottom board respectively; the first acquisition card and the second acquisition card are electrically connected through the serial port;

[0013] The host computer is electrically connected to the first acquisition card and the second acquisition card;

[0014] The first acquisition card and the second acquisition card are the same acquisition card.

[0015] Optionally, the first acquisition card and the second acquisition card respectively include:

[0016] External fault detection module, signal conditioning module, frequency acquisition detection module, median module and MCU;

[0017] The output end of the external fault detection module is electrically connected to the MCU;

[0018] The input end of the signal conditioning module is electrically connected to the output end of the external fault detection module, and the output end is electrically connected to the input end of the median module;

[0019] The input end of the frequency acquisition detection module is electrically connected to the output end of the median circuit, and the output end is electrically connected to the MCU;

[0020] The MCU is electrically connected to the host computer.

[0021] Optionally, the system further comprises:

[0022] The external fault detection module output end of the first acquisition card is also electrically connected to the external fault detection module input end of the second acquisition card, and the MCU output end of the first acquisition card is also electrically connected to the MCU input end of the second acquisition card.

[0023] Optionally, the external fault detection module includes:

[0024] A constant current source circuit, a first operational amplifier, a switch, a filter, and an analog-to-digital converter;

[0025] The constant current source circuit is electrically connected to the switch, the switch is electrically connected to the first operational amplifier, the first operational amplifier is electrically connected to the filter, the filter is electrically connected to the analog-to-digital converter, and the analog-to-digital converter is electrically connected to the MCU.

[0026] Optionally, the frequency acquisition and detection module includes:

[0027] a second operational amplifier, a third operational amplifier, a fourth operational amplifier, a second resistor, a third resistor, a fourth resistor, and a power supply;

[0028] The second operational amplifier input terminal and the third operational amplifier input terminal are electrically connected to the signal conditioning module output terminal, the second operational amplifier output terminal and the third operational amplifier output terminal are electrically connected to the median module input terminal, the median circuit output terminal is electrically connected to the fourth operational amplifier input terminal; the fourth operational amplifier output terminal is electrically connected to the MCU input terminal;

[0029] The second resistor is connected in parallel to both ends of the fourth operational amplifier, and the third resistor, the fourth resistor and the power supply are connected in series between the output end of the fourth operational amplifier and the input end of the MCU.

[0030] In a second aspect, an embodiment of the present invention provides a magnetoresistive sensor detection method, wherein the magnetoresistive sensor to be tested is electrically connected to a first resistor in a magnetoresistive sensor acquisition system to perform magnetoresistive sensor detection, wherein the magnetoresistive sensor acquisition system is the magnetoresistive sensor acquisition system according to any one of the claims; the detection method comprises:

[0031] S10, obtaining the real-time voltage value of the magnetoresistive sensor to be tested in the magnetoresistive sensor acquisition system, and determining whether the voltage value is zero;

[0032] S20, when the voltage value is zero, the host computer issues a first instruction to close the switch of the first acquisition card, and obtains the first real-time voltage value and the second real-time voltage value respectively acquired by the first acquisition card and the second acquisition card at this time;

[0033] S30, acquiring a first magnetoresistive sensor resistance and a second magnetoresistive sensor resistance according to the first real-time voltage value, the second real-time voltage value and the current value of the constant current source circuit;

[0034] S40 , comparing the resistance of the first magnetoresistance sensor with the resistance of the second magnetoresistance sensor to obtain an error between the resistance of the first magnetoresistance sensor and the resistance of the second magnetoresistance sensor, and generating an alarm if the error is greater than 0.1%.

[0035] Optionally, the S40 further includes:

[0036] If the error is less than or equal to 0.1%, comparing the resistance of the first magnetoresistive sensor with the actual resistance of the magnetoresistive sensor to be measured;

[0037] When the resistance of the first magnetoresistive sensor is different from the actual resistance of the magnetoresistive sensor to be measured, an alarm is issued.

[0038] Optionally, the S40 further includes:

[0039] When the resistance of the first magnetoresistive sensor is different from the actual resistance of the magnetoresistive sensor to be measured, obtaining a ratio of the resistance of the first magnetoresistive sensor to the actual resistance;

[0040] When the ratio of the resistance of the first magnetoresistive sensor to the real resistance is 2, it is a disconnection fault;

[0041] When the ratio of the resistance of the first magnetoresistive sensor to the real resistance is 0.5, it is a short circuit fault;

[0042] When the ratio of the resistance of the first magnetoresistive sensor to the actual resistance is 0.5-2 and is not equal to 1, it is an aging fault.

[0043] Optionally, the S30 includes:

[0044] S31, obtaining a third magnetoresistance sensor resistance and a fourth magnetoresistance sensor resistance according to the first real-time voltage value, the second real-time voltage value and the current value of the constant current source circuit;

[0045] S32, inputting the third magnetoresistance sensor resistance and the fourth magnetoresistance sensor resistance into the following formulas respectively to obtain the first magnetoresistance sensor resistance and the second magnetoresistance sensor resistance:

[0046]

[0047] Among them, R 磁阻 is the first magnetoresistive sensor resistor or the second magnetoresistive sensor resistor, R1 is the resistance value of the first resistor, R 测 is the third magnetoresistive sensor resistor or the fourth magnetoresistive sensor resistor.

[0048] Optionally, the S40 further includes:

[0049] When the resistance of the first magnetoresistive sensor is the same as the actual resistance of the magnetoresistive sensor to be measured, the resistance of the first magnetoresistive sensor is stored in the first acquisition card.

[0050] (III) Beneficial effects

[0051] The beneficial effects of the present invention are as follows: the acquisition system and detection method of a magnetoresistive sensor of the present invention, due to the provision of an acquisition card, can detect external faults such as disconnection, short circuit and aging of the magnetoresistive sensor compared to the prior art. At the same time, by providing a first acquisition card and a second acquisition card, it can increase the accuracy of magnetoresistive sensor diagnosis. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is a structural block diagram of a magnetoresistive sensor acquisition system according to Embodiment 1 of the present invention;

[0053] Figure 2 This is a specific circuit block diagram of a magnetoresistive sensor acquisition system in Embodiment 1 of the present invention;

[0054] Figure 3 is a circuit diagram of a median circuit in Embodiment 1 of the present invention;

[0055] Figure 4 Schematic diagram of a flow chart of a detection method of a magnetoresistive sensor in Embodiment 2 of the present invention;

[0056] Figure 5 This is an output effect diagram of the median circuit in Example 1 of the present invention. DETAILED DESCRIPTION

[0057] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0058] An acquisition system and a detection method for a magnetoresistive sensor proposed in an embodiment of the present invention are provided to solve the technical problem that the magnetoresistive sensor cannot be fully detected and the detection accuracy is low in the prior art. The present invention provides a first acquisition card and a second acquisition card, which can detect external faults such as disconnection, short circuit and aging of the magnetoresistive sensor, and at the same time increase the accuracy of magnetoresistive sensor diagnosis.

[0059] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0060] Example 1

[0061] See also Figure 1 A magnetoresistive sensor acquisition system according to an embodiment of the present invention is used to detect a magnetoresistive sensor in the gear speed measurement in the industrial control field where the speed needs to be acquired. The acquisition system includes:

[0062] Terminal board, first resistor, first acquisition card, second acquisition card, bottom board and host computer;

[0063] The first resistor is electrically connected to the terminal board via a DB37 line, the terminal board is electrically connected to the base board, the first acquisition card and the second acquisition card are fixed on the base board via slots on the base board, and are electrically connected to the base board respectively; the first acquisition card and the second acquisition card are electrically connected via a serial port;

[0064] The host computer is electrically connected to the first acquisition card and the second acquisition card;

[0065] The first acquisition card and the second acquisition card are the same acquisition card.

[0066] In a specific implementation process, the first resistor is welded on the terminal board;

[0067] The slots of the baseboard are combined through different pull-up and pull-down resistors, that is, each slot is set with a unique combination of resistance values, so that the acquisition card can determine which slot it belongs to by detecting these resistors when it starts.

[0068] For example, suppose there is an available GPIO pin, slot 1 connects a specific resistor between the GPIO pin and ground as a pull-down resistor; slot 2 connects another resistor of different resistance between the GPIO pin and power as a pull-up resistor; and there is also an unconnected GPIO pin at the corresponding position on the acquisition card;

[0069] When the capture card is inserted into the slot, the status of the GPIO pin is automatically read. If the pin reads a low level, it means that the capture card is in slot 1. If the pin reads a high level, it means that the capture card is in slot 2.

[0070] In this embodiment, the first acquisition card and the second acquisition card respectively include:

[0071] External fault detection module, signal conditioning module, frequency acquisition detection module, median module and MCU;

[0072] The output end of the external fault detection module is electrically connected to the MCU;

[0073] The input end of the signal conditioning module is electrically connected to the output end of the external fault detection module, and the output end is electrically connected to the input end of the median module;

[0074] The input end of the frequency acquisition detection module is electrically connected to the output end of the median circuit, and the output end is electrically connected to the MCU;

[0075] The MCU is electrically connected to the host computer.

[0076] like Figure 1 As shown, the first acquisition card is the main card, the second acquisition card is the standby card, and the circuits of the main card and the standby card are the same.

[0077] The signal conditioning module is a low-pass filter that filters out waveforms greater than the sampling frequency.

[0078] In a specific implementation process, the system further includes:

[0079] The external fault detection module output end of the first acquisition card is also electrically connected to the external fault detection module input end of the second acquisition card, and the MCU output end of the first acquisition card is also electrically connected to the MCU input end of the second acquisition card.

[0080] In this embodiment, the external fault detection module includes:

[0081] A constant current source circuit, a first operational amplifier, a switch, a filter, and an analog-to-digital converter;

[0082] The constant current source circuit is electrically connected to the switch, the switch is electrically connected to the first operational amplifier, the first operational amplifier is electrically connected to the filter, the filter is electrically connected to the analog-to-digital converter, and the analog-to-digital converter is electrically connected to the MCU.

[0083] See also Figure 2 , the frequency acquisition detection module includes:

[0084] a second operational amplifier, a third operational amplifier, a fourth operational amplifier, a second resistor, a third resistor, a fourth resistor, and a power supply;

[0085] The second operational amplifier input terminal and the third operational amplifier input terminal are electrically connected to the signal conditioning module output terminal, the second operational amplifier output terminal and the third operational amplifier output terminal are electrically connected to the median module input terminal, the median circuit output terminal is electrically connected to the fourth operational amplifier input terminal; the fourth operational amplifier output terminal is electrically connected to the MCU input terminal;

[0086] The second resistor is connected in parallel to both ends of the fourth operational amplifier, and the third resistor, the fourth resistor and the power supply are connected in series between the output end of the fourth operational amplifier and the input end of the MCU.

[0087] like Figure 3 As shown, the median circuit specifically includes:

[0088] A forward diode, a reverse diode, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a fifth operational amplifier, and a sixth operational amplifier;

[0089] The positive signal of the AC voltage signal sensed by the magnetoresistive sensor passes through the forward diode, and the negative signal is cut off by the reverse diode. The positive voltage signal passes through the third capacitor and then the sixth operational amplifier, and then is filtered into a positive DC voltage by the seventh resistor and the first capacitor.

[0090] The negative voltage signal of the AC voltage signal sensed by the magnetoresistive sensor passes through the reverse diode, and the positive signal is cut off by the reverse diode. The negative voltage signal passes through the fifth operational amplifier after filtering by the fourth capacitor, and then is filtered into a negative DC voltage by the fifth resistor and the second capacitor.

[0091] The positive DC voltage and the negative DC voltage are divided by the sixth resistor and the eighth resistor to output the median DC voltage of the voltage signal, such as Figure 5 shown.

[0092] In a specific implementation process, the first acquisition card and the second acquisition card further include: an isolation module;

[0093] The isolation module is arranged between the MCU and the external fault detection module, and is electrically connected to the MCU and the external fault detection module respectively;

[0094] Furthermore, the isolation module is arranged between the MCU and the frequency acquisition and detection module, and is electrically connected to the MCU and the frequency acquisition and detection module respectively.

[0095] In this embodiment, taking the first acquisition card as an example, the specific circuit principle is as follows:

[0096] A constant current is generated by the constant current source circuit, which is connected in parallel to GND (the reference ground plane on the circuit) through the magnetoresistive sensor and the first resistor. At this time, a DC component is introduced into the AC voltage signal on the magnetoresistive sensor and the first resistor. The DC component passes through the first operational amplifier and the filter. While ensuring that the normal sampling signal is not affected, the DC component is filtered out, collected by the analog-to-digital converter, and then input into the MCU through the isolation module.

[0097] Furthermore, the AC voltage signal on the magnetoresistive sensor and the first resistor passes through the signal conditioning module and is input into the positive end of the frequency acquisition circuit in the frequency acquisition detection module. At the same time, the circuit in the median module is input into the negative end of the circuit in the frequency acquisition detection module, and the median DC voltage of the voltage signal is output and input into the frequency acquisition detection module.

[0098] In the frequency acquisition and detection module, when the AC voltage signal is greater than the median DC voltage of the AC voltage signal, the fourth operational amplifier outputs a low level.

[0099] The low level output by the fourth operational amplifier passes through the fourth resistor and the isolation module and reaches the MCU.

[0100] In this embodiment, when the magnetoresistive sensor is disconnected, the first resistor is required to provide a path to GND for the constant current source circuit of the first acquisition card, so that the constant current source circuit of the first acquisition card can work normally, and the analog digital sensor can clearly collect an accurate voltage. The normal magnetoresistive sensor resistance is about 400-1000 ohms, so the first resistor needs to be of the same order of magnitude as the magnetoresistive sensor.

[0101] A magnetoresistive sensor acquisition system in this embodiment is installed inside an industrial control cabinet where gear speed measurement is required, and is close to a specific area of ​​the gear, thereby ensuring that the magnetoresistive sensor can accurately capture the magnetic field signal generated by the gear rotation.

[0102] A magnetoresistive sensor acquisition system of the present embodiment is provided with a first acquisition card and a second acquisition card, and at the same time improves the sampling circuit, enhances the anti-interference capability when sampling the magnetoresistive sensor, and can detect external faults such as disconnection, short circuit and aging of the magnetoresistive sensor.

[0103] Example 2

[0104] See also Figure 4A magnetoresistive sensor detection method according to an embodiment of the present invention includes electrically connecting the magnetoresistive sensor to be detected to a first resistor in a magnetoresistive sensor acquisition system to perform magnetoresistive sensor detection. The magnetoresistive sensor acquisition system is any of the magnetoresistive sensor acquisition systems described in Embodiment 1. The detection method includes:

[0105] Step S10, obtaining the real-time voltage value of the magnetoresistive sensor to be tested in the magnetoresistive sensor acquisition system, and determining whether the voltage value is zero;

[0106] Step S20: When the voltage value is zero, the host computer issues a first instruction to close the switch of the first acquisition card, and obtains the first real-time voltage value and the second real-time voltage value respectively acquired by the first acquisition card and the second acquisition card;

[0107] When the voltage value is not 0, an alarm is issued.

[0108] Step S30, obtaining the first magnetoresistance sensor resistance and the second magnetoresistance sensor resistance according to the first real-time voltage value, the second real-time voltage value and the current value of the constant current source circuit;

[0109] Step S40: Compare the resistance of the first magnetoresistance sensor with the resistance of the second magnetoresistance sensor to obtain an error between the resistance of the first magnetoresistance sensor and the resistance of the second magnetoresistance sensor. If the error is greater than 0.1%, an alarm is generated.

[0110] In a specific implementation process, before step S10, the following steps are also included:

[0111] S00, start the magnetoresistive sensor acquisition system and ensure that all hardware in the system are connected correctly and are in a stable operating state.

[0112] In this embodiment, step S40 further includes:

[0113] If the error is less than or equal to 0.1%, comparing the resistance of the first magnetoresistive sensor with the actual resistance of the magnetoresistive sensor to be measured;

[0114] When the resistance of the first magnetoresistive sensor is different from the actual resistance of the magnetoresistive sensor to be measured, an alarm is issued.

[0115] When the resistance of the first magnetoresistive sensor is different from the actual resistance of the magnetoresistive sensor to be measured, obtaining a ratio of the resistance of the first magnetoresistive sensor to the actual resistance;

[0116] When the ratio of the resistance of the first magnetoresistive sensor to the real resistance is 2, it is a disconnection fault;

[0117] When the ratio of the resistance of the first magnetoresistive sensor to the real resistance is 0.5, it is a short circuit fault;

[0118] When the ratio of the resistance of the first magnetoresistive sensor to the actual resistance is 0.5-2 and is not equal to 1, it is an aging fault.

[0119] Furthermore, different alarm modes are set, including:

[0120] In step S10, the real-time voltage value of the magnetoresistive sensor to be tested in the magnetoresistive sensor acquisition system is obtained, and it is determined whether the voltage value is zero; when the voltage value is 0, a Class A alarm is issued;

[0121] In step S40, the resistance of the first magnetoresistance sensor is compared with the resistance of the second magnetoresistance sensor to obtain an error between the resistance of the first magnetoresistance sensor and the resistance of the second magnetoresistance sensor. If the error is greater than 0.1%, a Class B alarm is issued.

[0122] When the resistance of the first magnetoresistive sensor is different from the actual resistance of the magnetoresistive sensor to be measured, an alarm is issued.

[0123] When the resistance of the first magnetoresistive sensor is different from the actual resistance of the magnetoresistive sensor to be measured, obtaining a ratio of the resistance of the first magnetoresistive sensor to the actual resistance;

[0124] When the ratio of the resistance of the first magnetoresistive sensor to the actual resistance is 2, a Class C alarm is issued;

[0125] When the ratio of the resistance of the first magnetoresistive sensor to the actual resistance is 0.5, a level D alarm is issued;

[0126] When the ratio of the resistance of the first magnetoresistive sensor to the actual resistance is 0.5-2 and is not equal to 1, a Class E alarm is issued.

[0127] Among them, the specific manifestations of each level of alarm are:

[0128] A-level alarm: "Voltage value is 0-A-level alarm" appears on the display screen of the host computer, and the red light turns on and flashes at intervals of 0.5s;

[0129] Class B alarm: "Acquisition card abnormality - Class B alarm" appears on the display screen of the host computer, and a yellow light turns on and flashes at intervals of 0.5s;

[0130] C-level alarm: "Disconnection fault-C-level alarm" appears on the display screen of the host computer, and the blue light turns on and flashes at intervals of 0.5s;

[0131] D-level alarm: "Short circuit fault-D-level alarm" appears on the display screen of the host computer, and the green light turns on and flashes at intervals of 0.5s;

[0132] E-level alarm: "Aging fault - E-level alarm" appears on the display screen of the host computer.

[0133] In this embodiment, step S30 includes:

[0134] Step S31, obtaining the third magnetoresistance sensor resistance and the fourth magnetoresistance sensor resistance according to the first real-time voltage value, the second real-time voltage value and the current value of the constant current source circuit;

[0135] Specifically, the third magnetoresistive sensor resistance and the fourth magnetoresistive sensor resistance are obtained according to Ohm's law (R=V / I).

[0136] Step S32: Input the third magnetoresistance sensor resistance and the fourth magnetoresistance sensor resistance into the following formulas to obtain the first magnetoresistance sensor resistance and the second magnetoresistance sensor resistance:

[0137]

[0138] Among them, R 磁阻 is the first magnetoresistive sensor resistor or the second magnetoresistive sensor resistor, R1 is the resistance value of the first resistor, R 测 is the third magnetoresistive sensor resistor or the fourth magnetoresistive sensor resistor.

[0139] In this embodiment, step S40 further includes:

[0140] When the resistance of the first magnetoresistive sensor is the same as the actual resistance of the magnetoresistive sensor to be measured, the resistance of the first magnetoresistive sensor is stored in the first acquisition card.

[0141] Specifically, when the resistance of the first magnetoresistive sensor is the same as the actual resistance of the magnetoresistive sensor to be measured, the host computer records the resistance of the current magnetoresistive sensor and sends the resistance value to the flash (non-volatile sensor) of the MCU. The resistance value supports power-off preservation.

[0142] In this embodiment, step S20 further includes:

[0143] When one of the first acquisition card and the second acquisition card is abnormal, the mode is switched to single card mode, a real-time voltage value is obtained, and the resistance of the magnetoresistive sensor to be measured is obtained according to the real-time voltage value, and compared with the actual resistance. When the resistance of the first magnetoresistive sensor is different from the actual resistance of the magnetoresistive sensor to be measured, an alarm is issued.

[0144] When both the first acquisition card and the second acquisition card are normal, it is a dual-card mode, that is, the above steps S10 to S40 are executed, and the first acquisition card is the main card and the second acquisition card is the standby card; that is, in step S10, the real-time voltage value of the magnetoresistive sensor to be tested in the magnetoresistive sensor acquisition system is obtained through the first acquisition card, and sent to the host computer, the host computer receives the real-time voltage value of the magnetoresistive sensor to be tested in the magnetoresistive sensor acquisition system, and performs subsequent operations.

[0145] In this embodiment, by setting different alarm modes, different external fault conditions can be detected to make the detection more comprehensive. Setting the first acquisition card and the second acquisition card at the same time can not only improve the accuracy of detection, but also provide redundant equipment. When an acquisition card has an abnormality, it can be quickly replaced to ensure that the gear speed system does not stop.

[0146] In the description of the present invention, it should be understood that 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 of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0147] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0148] In the present invention, unless otherwise clearly specified and limited, when a first feature is “on” or “below” a second feature, it may be that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, when a first feature is “above”, “above” or “above” a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it may simply mean that the first feature is higher in level than the second feature. When a first feature is “below”, “below” or “below” a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it may simply mean that the first feature is lower in level than the second feature.

[0149] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0150] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A magnetoresistive sensor acquisition system, characterized in that: Used for detecting the magnetoresistive sensor in the gear speed measurement in the industrial control field where the speed needs to be collected, the collection system includes: Terminal board, first resistor, first acquisition card, second acquisition card, bottom board and host computer; The first resistor is electrically connected to the terminal board, the terminal board is electrically connected to the bottom board, the first acquisition card and the second acquisition card are fixed on the bottom board through the slots of the bottom board, and are electrically connected to the bottom board respectively; the first acquisition card and the second acquisition card are electrically connected through the serial port; The host computer is electrically connected to the first acquisition card and the second acquisition card; The first acquisition card and the second acquisition card are the same acquisition card.

2. The magnetoresistive sensor acquisition system according to claim 1, characterized in that: The first acquisition card and the second acquisition card respectively include: External fault detection module, signal conditioning module, frequency acquisition detection module, median module and MCU; The output end of the external fault detection module is electrically connected to the MCU; The input end of the signal conditioning module is electrically connected to the output end of the external fault detection module, and the output end is electrically connected to the input end of the median module; The input end of the frequency acquisition detection module is electrically connected to the output end of the median circuit, and the output end is electrically connected to the MCU; The MCU is electrically connected to the host computer.

3. The magnetoresistive sensor acquisition system according to claim 2, characterized in that: The system further comprises: The external fault detection module output end of the first acquisition card is also electrically connected to the external fault detection module input end of the second acquisition card, and the MCU output end of the first acquisition card is also electrically connected to the MCU input end of the second acquisition card.

4. The magnetoresistive sensor acquisition system according to claim 2, characterized in that: The external fault detection module comprises: A constant current source circuit, a first operational amplifier, a switch, a filter, and an analog-to-digital converter; The constant current source circuit is electrically connected to the switch, the switch is electrically connected to the first operational amplifier, the first operational amplifier is electrically connected to the filter, the filter is electrically connected to the analog-to-digital converter, and the analog-to-digital converter is electrically connected to the MCU.

5. The magnetoresistive sensor acquisition system according to claim 2, characterized in that: The frequency acquisition detection module includes: a second operational amplifier, a third operational amplifier, a fourth operational amplifier, a second resistor, a third resistor, a fourth resistor, and a power supply; The second operational amplifier input terminal and the third operational amplifier input terminal are electrically connected to the signal conditioning module output terminal, the second operational amplifier output terminal and the third operational amplifier output terminal are electrically connected to the median module input terminal, the median circuit output terminal is electrically connected to the fourth operational amplifier input terminal; the fourth operational amplifier output terminal is electrically connected to the MCU input terminal; The second resistor is connected in parallel to both ends of the fourth operational amplifier, and the third resistor, the fourth resistor and the power supply are connected in series between the output end of the fourth operational amplifier and the input end of the MCU.

6. A magnetoresistive sensor detection method, characterized in that: The magnetoresistive sensor to be tested is electrically connected to a first resistor in a magnetoresistive sensor acquisition system to perform magnetoresistive sensor detection, wherein the magnetoresistive sensor acquisition system is the magnetoresistive sensor acquisition system according to any one of claims 1 to 5; The detection method comprises: S10, obtaining the real-time voltage value of the magnetoresistive sensor to be tested in the magnetoresistive sensor acquisition system, and determining whether the voltage value is zero; S20, when the voltage value is zero, the host computer issues a first instruction to close the switch of the first acquisition card, and obtains the first real-time voltage value and the second real-time voltage value respectively acquired by the first acquisition card and the second acquisition card at this time; S30, acquiring a first magnetoresistive sensor resistance and a second magnetoresistive sensor resistance according to the first real-time voltage value, the second real-time voltage value and the current value of the constant current source circuit; S40 , comparing the resistance of the first magnetoresistance sensor with the resistance of the second magnetoresistance sensor to obtain an error between the resistance of the first magnetoresistance sensor and the resistance of the second magnetoresistance sensor, and generating an alarm if the error is greater than 0.1%.

7. The magnetoresistive sensor detection method according to claim 6, characterized in that: The S40 further includes: If the error is less than or equal to 0.1%, comparing the resistance of the first magnetoresistive sensor with the actual resistance of the magnetoresistive sensor to be measured; When the resistance of the first magnetoresistive sensor is different from the actual resistance of the magnetoresistive sensor to be measured, an alarm is issued.

8. The magnetoresistive sensor detection method according to claim 7, characterized in that: The S40 further includes: When the resistance of the first magnetoresistive sensor is different from the actual resistance of the magnetoresistive sensor to be measured, obtaining a ratio of the resistance of the first magnetoresistive sensor to the actual resistance; When the ratio of the resistance of the first magnetoresistive sensor to the real resistance is 2, it is a disconnection fault; When the ratio of the resistance of the first magnetoresistive sensor to the real resistance is 0.5, it is a short circuit fault; When the ratio of the resistance of the first magnetoresistive sensor to the actual resistance is 0.5-2 and is not equal to 1, it is an aging fault.

9. The magnetoresistive sensor detection method according to claim 6, characterized in that: The S30 includes: S31, obtaining a third magnetoresistance sensor resistance and a fourth magnetoresistance sensor resistance according to the first real-time voltage value, the second real-time voltage value and the current value of the constant current source circuit; S32, inputting the third magnetoresistance sensor resistance and the fourth magnetoresistance sensor resistance into the following formulas respectively to obtain the first magnetoresistance sensor resistance and the second magnetoresistance sensor resistance: Among them, R 磁阻 is the first magnetoresistive sensor resistor or the second magnetoresistive sensor resistor, R1 is the resistance value of the first resistor, R 测 is the third magnetoresistive sensor resistor or the fourth magnetoresistive sensor resistor.

10. The magnetoresistive sensor detection method according to claim 7, characterized in that: The S40 further includes: When the resistance of the first magnetoresistive sensor is the same as the actual resistance of the magnetoresistive sensor to be measured, the resistance of the first magnetoresistive sensor is stored in the first acquisition card.

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