CN114019432A - Method and system for acquiring magnetic resistance type rotating speed signal with open circuit detection - Google Patents
Method and system for acquiring magnetic resistance type rotating speed signal with open circuit detection Download PDFInfo
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- CN114019432A CN114019432A CN202111298384.6A CN202111298384A CN114019432A CN 114019432 A CN114019432 A CN 114019432A CN 202111298384 A CN202111298384 A CN 202111298384A CN 114019432 A CN114019432 A CN 114019432A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
- G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
- G01R33/09—Magnetoresistive devices
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
- G05B19/0423—Input/output
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/20—Pc systems
- G05B2219/24—Pc safety
- G05B2219/24215—Scada supervisory control and data acquisition
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Abstract
The invention discloses a method and a system for acquiring a magnetic resistance type rotating speed signal with open circuit detection, wherein the method comprises the following steps: filtering the alternating current sinusoidal signals with positive correlation between the amplitude and the frequency from the magnetoresistive sensor, and then dividing the signals into two paths; one path is subjected to direct current voltage lifting processing and then is compared with a set comparison level through a voltage comparator, and a comparison result is transmitted to the MCU for open circuit detection after being isolated by the optical coupler; and the other path is subjected to program control amplification and shaping and then is transmitted to the MCU for rotating speed signal acquisition through optical coupling isolation. The system comprises a filter circuit, a rotating speed signal acquisition circuit, an open circuit detection circuit and an MCU circuit; the rotating speed signal acquisition circuit comprises a program control amplification circuit, a comparison circuit, a triode switch circuit and an isolation circuit; the input end of the filter circuit is connected with the output end of the magnetic resistance sensor, and the output end of the filter circuit is simultaneously connected with the input end of the rotating speed signal acquisition circuit and the input end of the open circuit detection circuit. The detection of the connection state of the system and the magnetic resistance sensor is realized.
Description
Technical Field
The invention belongs to the technical field of signal acquisition and processing, and particularly relates to a method and a system for acquiring a magnetic resistance type rotating speed signal with open circuit detection.
Background
At present, large rotating equipment is widely applied, and plays an irreplaceable role particularly in the industrial field. In the application field of large industrial rotating equipment, rotating speed measurement is always a very important technology. Accurate and reliable rotating speed measurement plays a crucial role in monitoring and controlling the working condition of industrial equipment. During the operation of large industrial rotating equipment, any failure of the equipment can have very serious consequences, seriously affect the production safety and even harm the life safety of workers. Most of conventional rotating speed detection technologies only sample rotating speed signals, and do not judge transmission line faults, so that hidden risks exist, and therefore the invention provides a rotating speed signal acquisition technology capable of simultaneously detecting input transmission line faults, which is very necessary and has very important practical significance.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a method and a system for acquiring a reluctance type rotational speed signal with open circuit detection, aiming at the defects of the prior art.
In order to achieve the technical purpose, the technical scheme adopted by the invention is as follows:
a method of acquiring a magnetoresistive tachometer signal with open circuit detection, the method comprising:
filtering the alternating current sinusoidal signals with positive correlation between the amplitude and the frequency from the magnetoresistive sensor, and then dividing the signals into two paths; one path is subjected to direct current voltage lifting processing and then is compared with a set comparison level through a voltage comparator, and a comparison result is transmitted to the MCU for open circuit detection after being isolated by the optical coupler; and the other path is subjected to program control amplification and shaping and then is transmitted to the MCU for rotating speed signal acquisition through optical coupling isolation.
A magnetic resistance type rotating speed signal acquisition system with open circuit detection comprises a filter circuit, a rotating speed signal acquisition circuit, an open circuit detection circuit and an MCU circuit;
the rotating speed signal acquisition circuit comprises a program control amplification circuit, a comparison circuit, a triode switch circuit and an isolation circuit;
the input end of the filter circuit is connected with the output end of the magnetic resistance sensor, the output end of the filter circuit is simultaneously connected with the input end of the rotating speed signal acquisition circuit and the input end of the open circuit detection circuit, the output end of the rotating speed signal acquisition circuit and the output end of the open circuit detection circuit are both connected with the MCU circuit, and the MCU circuit controls the amplification factor of the program control amplification circuit of the rotating speed signal acquisition circuit.
Preferably, the program-controlled amplifying circuit input end of the rotational speed signal collecting circuit is connected with the filtering circuit output end, the output end of the program-controlled amplifying circuit is connected with the comparison circuit input end, the comparison circuit output end is connected with the triode switch input end, the triode switch output end is connected with the isolation circuit input end, and the isolation circuit output end is connected with the MCU circuit input end.
Preferably, the open circuit detection circuit comprises a direct current level boost circuit, a voltage comparator and an optical coupler;
the input end of the voltage comparator is provided with a preset comparison level;
the input end of the direct current level lifting circuit is connected with the output end of the filter circuit; the output end of the direct current level lifting circuit is connected with the input end of the voltage comparator; and the output end of the voltage comparator is connected to the MCU circuit after being isolated by the optical coupler.
Preferably, the preset comparison level is obtained by dividing the voltage of the anode of the external power supply through two voltage dividing resistors, the setting of the voltage value of the divided resistor is determined according to the output signal characteristics of the magnetoresistive sensor and the voltage value behind the direct current level lifting circuit, and when the system works normally, the output voltage value of the direct current level lifting circuit is higher than the voltage value of the divided resistor, and the voltage comparator outputs a high level; when the system and the magnetic resistance sensor are in an open circuit, the output voltage value of the direct current level lifting circuit is lower than the resistance voltage dividing value, and the voltage comparator outputs a low level.
Preferably, the filter circuit includes a common mode choke coil and an RC band-pass filter circuit, and the common mode choke coil filters the common mode interference signal and then outputs the common mode interference signal to the outside after being filtered by the RC band-pass filter circuit.
The invention has the following beneficial effects:
after the method and the system for acquiring the reluctance type rotating speed signal with the open-circuit detection are adopted, the system and the reluctance sensor are monitored in a connection state, so that the real-time monitoring of the open circuit of the system is realized, the method has an important effect on the aspect of the open circuit detection of large industrial rotating equipment, and the function of monitoring the rotating speed of the large industrial rotating equipment in real time is realized. Compared with the prior art, the method can more reliably acquire and process the reluctance type rotating speed signal, better monitor the working condition of the equipment and has important significance for maintaining large-scale rotating equipment and production safety.
Drawings
FIG. 1 is a schematic diagram of a system of a magnetic resistance type rotational speed signal acquisition system with open circuit detection according to the present invention;
FIG. 2 is a schematic diagram of an open circuit detection circuit of the magnetoresistive rotational speed signal acquisition system with open circuit detection according to the present invention;
fig. 3 is a schematic circuit diagram of a magnetic resistance type rotational speed signal acquisition system with open circuit detection according to an embodiment of the present invention.
Detailed Description
Embodiments of the present invention are described in further detail below with reference to the accompanying drawings.
A method of acquiring a magnetoresistive tachometer signal with open circuit detection, the method comprising:
filtering the alternating current sinusoidal signals with positive correlation between the amplitude and the frequency from the magnetoresistive sensor, and then dividing the signals into two paths; one path is subjected to direct current voltage lifting processing and then is compared with a set comparison level through a voltage comparator, and a comparison result is transmitted to the MCU for open circuit detection after being isolated by the optical coupler; and the other path is subjected to program control amplification and shaping and then is transmitted to the MCU for rotating speed signal acquisition through optical coupling isolation.
Referring to fig. 1, a magnetoresistive rotational speed signal acquisition system with open circuit detection includes a filter circuit, a rotational speed signal acquisition circuit, an open circuit detection circuit, and an MCU circuit;
the rotating speed signal acquisition circuit comprises a program control amplification circuit, a comparison circuit, a triode switch circuit and an isolation circuit;
the input end of the filter circuit is connected with the output end of the magnetic resistance sensor, the output end of the filter circuit is simultaneously connected with the input end of the rotating speed signal acquisition circuit and the input end of the open circuit detection circuit, the output end of the rotating speed signal acquisition circuit and the output end of the open circuit detection circuit are both connected with the MCU circuit, and the MCU circuit controls the amplification factor of the program control amplification circuit of the rotating speed signal acquisition circuit.
When the device is specifically implemented, the input end of a program-controlled amplifying circuit of the rotating speed signal acquisition circuit is connected with the output end of a filter circuit, the output end of the program-controlled amplifying circuit is connected with the input end of a comparison circuit, the output end of the comparison circuit is connected with the input end of a triode switch, the output end of the triode switch is connected with the input end of an isolation circuit, and the output end of the isolation circuit is connected with the input end of an MCU circuit.
Referring to fig. 2, in specific implementation, the open circuit detection circuit includes a dc level boost circuit, a voltage comparator, and an optical coupler;
the input end of the voltage comparator is provided with a preset comparison level;
the input end of the direct current level lifting circuit is connected with the output end of the filter circuit; the output end of the direct current level lifting circuit is connected with the input end of the voltage comparator; and the output end of the voltage comparator is connected to the MCU circuit after being isolated by the optical coupler.
In specific implementation, the preset comparison level is obtained by dividing the voltage of the anode of the external power supply through two voltage dividing resistors, the setting of the voltage value of the divided resistor is determined according to the output signal characteristics of the magnetoresistive sensor and the voltage value behind the direct current level lifting circuit, and the conditions that when a system works normally, the output voltage value of the direct current level lifting circuit is higher than the voltage value of the divided resistor are met, and the voltage comparator outputs a high level; when the system and the magnetic resistance sensor are in an open circuit, the output voltage value of the direct current level lifting circuit is lower than the resistance voltage dividing value, and the voltage comparator outputs a low level.
Referring to fig. 3, in a specific implementation, the filter circuit includes a common mode choke coil and an RC band-pass filter circuit, and the common mode choke coil filters a common mode interference signal and then outputs the common mode interference signal to the outside after being filtered by the RC band-pass filter circuit. When an external reluctance type rotating speed signal is sent to the input end of the filter circuit, the signal is filtered through the common mode choke coil and the RC band-pass filter circuit, and at the moment, the signal is a sine alternating current signal with interference filtered.
For the rotating speed signal acquisition circuit, the signal filtered by the filter circuit is input into a program control amplifying circuit consisting of an operational amplifier and an analog multi-path gating switch. Since the amplitude of the magnetic resistance signal increases along with the increase of the frequency, the GAIN of the part of the circuit is controlled by a program, the MCU selects different amplification factors through the rotation speed, and the GAIN is controlled through pins GAIN1 and GAIN 2. The amplified rotation speed signal is input to the negative terminal of the voltage comparator, and the voltage comparator part forms a shaping circuit to convert sine wave into pulse signal. The output of the voltage comparator is connected to the triode, the pulse signal controls the conduction and the disconnection of a signal loop formed by the triode and the optocoupler, and finally the 3.3V standard pulse waveform is formed and input into the MCU.
For the open circuit detection circuit, as shown in fig. 2, which is a schematic block diagram of the open circuit detection circuit, the filtered reluctance type rotation speed signal is first subjected to dc component lifting and then input to the positive input end of the voltage comparator. The output of the voltage division circuit is connected to the negative end of the voltage comparator, the output of the voltage comparator is further output to the optical coupler, and the open-circuit detection signal is transmitted to the MCU for open-circuit diagnosis after the optical coupler is isolated.
The open circuit detection circuit shown in fig. 3 includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a first capacitor C1, a first comparator D1, a first voltage regulator tube Z1, a first choke coil L1, and a first optical coupler E1.
For the direct current level raising circuit part, the first choke coil L1 inputs the reluctance type rotating speed signals M + and M-, the first choke coil L1 outputs A point and is connected with one end of a first resistor R1, one end of a third resistor R3 and one end of a fourth resistor R4 and is connected with the reluctance signal acquisition processing module. The output B of the first choke coil L1 is connected to one end of a second resistor R2 and the cathode of a first regulator tube Z1. The other end of the first resistor R1 is connected with VSS, the other end of the second resistor R2 is connected with VCC, the anode of the first voltage regulator tube Z1 is connected with GND, and the other end of the third resistor R3 is connected with GND.
For the voltage comparator circuit part, the other end of the fourth resistor R4 is connected with one end of the first capacitor C1 and input to the positive end C point of the first comparator D1, and the other end of the first capacitor C1 is connected with GND. One end of a fifth resistor R5 and one end of a sixth resistor R6 are connected and input to the negative terminal D point of the first comparator D1, the other end of the fifth resistor R5 is connected with VCC, and the other end of the sixth resistor R6 is connected with GND. The first comparator D1 has VCC connected to the upper terminal and VSS connected to the lower terminal. One end of the seventh resistor R7 is connected to VCC, and the other end is connected to the output E point of the first comparator D1.
For the optical coupler isolation circuit part, the output E point of the first comparator D1 is connected with a first optical coupler E1.
In this embodiment, VCC is selected to be +15V, VSS is selected to be-15V, Z1 is selected to be a 4.7V voltage regulator, and the first comparator Z1 is selected to be LM 393. The first resistor R1 is selected to be 300k ohms, the third resistor R3 is selected to be 100k ohms, the fifth resistor R5 is selected to be 300k ohms and the sixth resistor R6 is selected to be 5.1k ohms. The first optical coupler E1 selects HCPL-181-00A.
As in the open circuit detection circuit shown in fig. 3, the first choke coil L1 suppresses input common mode interference. The first resistor R1 and the third resistor R3 divide VSS at open circuit. The second resistor R2 plays a protective role. The fifth resistor R5 and the sixth resistor R6 divide the voltage VCC, and input the voltage at the negative terminal of the first comparator D1. The first zener tube Z1 normally pulls up the dc component. The fourth resistor R4 and the first capacitor C1 function as an RC low pass filter. The first comparator D1 compares the preset value with the input value to determine whether there is an open circuit. The seventh resistor R7 pulls the first comparator D1 output high. The first optical coupler E1 isolates interference and transmits an open circuit detection signal through self opening.
Under normal conditions, the first voltage regulator tube Z1 raises the voltage at the point B to 4.7V and is coupled to the point A, and the signal passes through an RC low-pass filter circuit consisting of a fourth resistor R4 and a first capacitor C1 to filter high-frequency interference. Then the voltage is input to the negative end of the first comparator, the first comparator D1 compares the positive end 4.7V with the negative end preset voltage value 0.251V, the positive end voltage of the first comparator D1 is higher than the negative end preset voltage, the output of the first comparator D1 is positive, the first optical coupler E1 is turned on, and a normal signal is output to the MCU.
When the open circuit occurs, the voltage at the point B cannot be coupled to the point a, and the voltage at the point a is a negative voltage divided by the first resistor R1 and the third resistor R3. The signal passes through an RC low-pass filter circuit consisting of a fourth resistor R4 and a first capacitor C1, and high-frequency interference is filtered. The positive end of the first comparator D1 is negative voltage, the preset voltage value of the negative end is 0.251V, the output of the first comparator D1 is negative after comparison, the first optocoupler E1 is disconnected, and an open-circuit signal is output to the MCU, so that the detection of the open circuit of the input signal path is completed.
According to the method and the system for acquiring the reluctance type rotating speed signal with the open circuit detection, disclosed by the invention, the real-time monitoring of the open circuit of the system is realized by monitoring the connection state of the system and the reluctance sensor, so that the method and the system have an important effect on the open circuit detection of large industrial rotating equipment and realize the function of monitoring the rotating speed of the large industrial rotating equipment in real time. Compared with the prior art, the method can more reliably acquire and process the reluctance type rotating speed signal, better monitor the working condition of the equipment and has important significance for maintaining large-scale rotating equipment and production safety.
Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.
Claims (6)
1. A magnetic resistance type rotating speed signal acquisition method with open circuit detection is characterized in that: the method comprises the following steps:
filtering the alternating current sinusoidal signals with positive correlation between the amplitude and the frequency from the magnetoresistive sensor, and then dividing the signals into two paths; one path is subjected to direct current voltage lifting processing and then is compared with a set comparison level through a voltage comparator, and a comparison result is transmitted to the MCU for open circuit detection after being isolated by the optical coupler; and the other path is subjected to program control amplification and shaping and then is transmitted to the MCU for rotating speed signal acquisition through optical coupling isolation.
2. The utility model provides a take magnetic resistance type rotational speed signal acquisition system of open circuit detection which characterized in that: the system comprises a filter circuit, a rotating speed signal acquisition circuit, an open circuit detection circuit and an MCU circuit;
the rotating speed signal acquisition circuit comprises a program control amplification circuit, a comparison circuit, a triode switch circuit and an isolation circuit;
the input end of the filter circuit is connected with the output end of the magnetic resistance sensor, the output end of the filter circuit is simultaneously connected with the input end of the rotating speed signal acquisition circuit and the input end of the open circuit detection circuit, the output end of the rotating speed signal acquisition circuit and the output end of the open circuit detection circuit are both connected with the MCU circuit, and the MCU circuit controls the amplification factor of the program control amplification circuit of the rotating speed signal acquisition circuit.
3. A system according to claim 2, wherein the system comprises: the input end of a program-controlled amplifying circuit of the rotating speed signal acquisition circuit is connected with the output end of a filter circuit, the output end of the program-controlled amplifying circuit is connected with the input end of a comparison circuit, the output end of the comparison circuit is connected with the input end of a triode switch, the output end of the triode switch is connected with the input end of an isolation circuit, and the output end of the isolation circuit is connected with the input end of an MCU circuit.
4. A system according to claim 2, wherein the system comprises: the open circuit detection circuit comprises a direct current level lifting circuit, a voltage comparator and an optical coupler;
the input end of the voltage comparator is provided with a preset comparison level;
the input end of the direct current level lifting circuit is connected with the output end of the filter circuit; the output end of the direct current level lifting circuit is connected with the input end of the voltage comparator; and the output end of the voltage comparator is connected to the MCU circuit after being isolated by the optical coupler.
5. A magnetoresistive tachometer signal generator system with open circuit detection as claimed in claim 4, in which: the preset comparison level is obtained by dividing the voltage of the anode of the external power supply through two voltage dividing resistors, the setting of the voltage value of the divided resistor is determined according to the output signal characteristics of the magnetoresistive sensor and the voltage value behind the direct current level lifting circuit, and the conditions that when the system works normally, the output voltage value of the direct current level lifting circuit is higher than the voltage value of the divided resistor and the voltage comparator outputs high level are met; when the system and the magnetic resistance sensor are in an open circuit, the output voltage value of the direct current level lifting circuit is lower than the resistance voltage dividing value, and the voltage comparator outputs a low level.
6. A system according to claim 2, wherein the system comprises: the filter circuit comprises a common mode choke coil and an RC band-pass filter circuit, and the common mode choke coil filters common mode interference signals and then outputs the signals after filtering through the RC band-pass filter circuit.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111298384.6A CN114019432A (en) | 2021-11-04 | 2021-11-04 | Method and system for acquiring magnetic resistance type rotating speed signal with open circuit detection |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111298384.6A CN114019432A (en) | 2021-11-04 | 2021-11-04 | Method and system for acquiring magnetic resistance type rotating speed signal with open circuit detection |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103308704A (en) * | 2013-05-24 | 2013-09-18 | 江阴市江凌科技有限公司 | Inverse speed measuring circuit |
| CN206601620U (en) * | 2017-02-08 | 2017-10-31 | 中国第一汽车股份有限公司 | A kind of wheel speed processing being used in automobile anti-lock braking controller and diagnostic circuit |
| CN109839511A (en) * | 2017-11-27 | 2019-06-04 | 中国航空工业集团公司西安航空计算技术研究所 | A kind of tach signal Acquisition Circuit |
| CN211979167U (en) * | 2020-02-28 | 2020-11-20 | 合肥同智机电控制技术有限公司 | High-efficient cable open circuit detection circuitry of rectifying certainly |
| CN113419082A (en) * | 2021-06-21 | 2021-09-21 | 湖南行必达网联科技有限公司 | Input signal processing circuit with detection and diagnosis functions |
-
2021
- 2021-11-04 CN CN202111298384.6A patent/CN114019432A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103308704A (en) * | 2013-05-24 | 2013-09-18 | 江阴市江凌科技有限公司 | Inverse speed measuring circuit |
| CN206601620U (en) * | 2017-02-08 | 2017-10-31 | 中国第一汽车股份有限公司 | A kind of wheel speed processing being used in automobile anti-lock braking controller and diagnostic circuit |
| CN109839511A (en) * | 2017-11-27 | 2019-06-04 | 中国航空工业集团公司西安航空计算技术研究所 | A kind of tach signal Acquisition Circuit |
| CN211979167U (en) * | 2020-02-28 | 2020-11-20 | 合肥同智机电控制技术有限公司 | High-efficient cable open circuit detection circuitry of rectifying certainly |
| CN113419082A (en) * | 2021-06-21 | 2021-09-21 | 湖南行必达网联科技有限公司 | Input signal processing circuit with detection and diagnosis functions |
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