CN110687856A - Dual-redundancy discrete inductive position sensor signal intelligent acquisition and processing device - Google Patents
Dual-redundancy discrete inductive position sensor signal intelligent acquisition and processing device Download PDFInfo
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- CN110687856A CN110687856A CN201911088023.1A CN201911088023A CN110687856A CN 110687856 A CN110687856 A CN 110687856A CN 201911088023 A CN201911088023 A CN 201911088023A CN 110687856 A CN110687856 A CN 110687856A
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Abstract
The invention discloses a dual-redundancy discrete inductive position sensor signal intelligent acquisition and processing device, which comprises a terminal board, a first detection module and a second detection module; and the terminal board is provided with a high-impedance differential amplification circuit, an excitation power supply redundant output circuit, a power supply redundant circuit and a switching value position signal redundant output circuit. The invention realizes double redundancy by arranging the first module and the second module which have the same structure, namely, the main detection board outputs a normal excitation power supply and performs complete logic operation and position output functions on received signals under the normal working state. At the moment, the slave detection board is in a standby state, whether the main detection board breaks down or not is continuously detected through the fault input pin, when the main detection board breaks down, the main detection board automatically breaks off the output signal, and the slave detection board immediately starts to work. Therefore, system redundancy is realized, and the reliability of the system is improved. Under a further normal working state, plugging and maintenance of any detection board can be carried out in a charged mode, and maintenance time of the system is remarkably shortened.
Description
Technical Field
The invention relates to the technical field of signal acquisition and processing, in particular to a dual-redundancy discrete inductive position sensor signal intelligent acquisition and processing device.
Background
At present, an electromagnetic inductive position sensor refers to a sensor which can sense the position of an object to be measured and convert the position into an output electric signal. The electromagnetic inductive position sensor is non-contact measurement, has no abrasion, good precision retentivity, simple structure, reliable operation, long service life, high sensitivity, simple protection and the like. Especially, the environment adaptability is strong, and the high humidity, high temperature and thermal deformation resistance are realized. Therefore, the method is widely applied to the fields of nuclear power, military industry, automobiles, industrial robots and the like which need to acquire position signals.
The traditional signal acquisition and processor of the electromagnetic induction position sensor adopts an operational amplifier circuit and a comparison circuit, and compares an acquired voltage value with a set value so as to judge whether an object reaches a position and output a switching value signal. In addition, due to the limitation of circuit design, effective redundancy design cannot be carried out, and the reliability is low.
In the face of the new requirements of high precision and high reliability of the signal acquisition and processor of the electromagnetic position sensor at present, the existing measuring circuit can not meet the requirements. A signal acquisition and processor with high measurement precision and high reliability is required to meet the requirement of position measurement in special fields.
Disclosure of Invention
The invention aims to provide a dual-redundancy discrete type induction position sensor signal intelligent acquisition and processing device which can realize high precision and high reliability of position sensor measurement.
The technical scheme adopted by the invention is as follows:
the dual-redundancy discrete inductive position sensor signal intelligent acquisition and processing device comprises a terminal board, a first detection module and a second detection module; the terminal board is provided with a high-impedance differential amplifying circuit, an excitation power supply redundant output circuit, a power supply redundant circuit and a switching value position signal redundant output circuit;
the first detection module is provided with a signal processing circuit, an excitation power circuit, a power conversion circuit, a central processing unit and a relay output end circuit; the input end of the high-resistance state differential amplifying circuit is connected with the signal output end of the position sensor, the output end of the high-resistance state differential amplifying circuit is connected with the input end of the signal processing circuit, the output end of the central processing unit is connected with the input end of the excitation power supply redundant output circuit through the excitation power supply circuit, and the output end of the excitation power supply redundant output circuit is connected with the input end of the position sensor;
the control output end of the central processing unit is connected with the input end of the switching value redundancy circuit through the relay output circuit, and the switching value redundancy circuit is used for outputting a switching value position signal;
the input end of the power supply redundant circuit is connected with the power supply inlet wire, and the output end of the power supply redundant circuit is connected with the input end of the central processing unit through the power supply conversion circuit;
the second detection module and the first detection module have the same structure, and the connection relationship between the second detection module and the terminal board is the same as that between the first detection module and the terminal board.
The relay output circuit comprises seven switching value control circuits, namely one path of control excitation power output, one path of control power input, one path of control fault output and four paths of position signal switching value output.
The central processing unit is the DSP28335 and its auxiliary peripheral circuits.
The signal processing circuit is used for converting the alternating voltage signal into a voltage signal of 0 ~ 3V, transmitting the voltage signal to the DSP analog-to-digital conversion module and converting the analog voltage signal into a digital signal.
The first detection module and the second detection module are respectively and fixedly arranged on the first detection plate and the second detection plate with the interface terminals.
The interface terminal is an anti-error plugging interface terminal.
The output signal of the position sensor is converted into a corresponding voltage signal through a high internal resistance differential circuit, and the analog voltage signal is converted into a digital signal through a DSP analog-to-digital conversion module for processing.
The invention realizes double redundancy by arranging the first module and the second module which have the same structure, namely, the main detection board outputs a normal excitation power supply and performs complete logic operation and position output functions on received signals under the normal working state. At the moment, the slave detection board is in a standby state, whether the main detection board breaks down or not is continuously detected through the fault input pin, when the main detection board breaks down, the power supply of the main detection board is automatically disconnected, and the slave detection board immediately starts to work. Therefore, system redundancy is realized, and the reliability of the system is improved. Under a further normal working state, plugging and maintenance of any detection board can be carried out in a charged mode, and maintenance time of the system is remarkably shortened.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a functional block diagram of the present invention;
FIG. 2 is a schematic diagram of the state of the relay output circuit when the main detection board works according to the present invention;
fig. 3 is a schematic diagram of the state of the relay output circuit when the slave detection board works according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive effort based on the embodiments of the present invention, are within the scope of the present invention.
As shown in fig. 1, 2 and 3, the present invention includes a terminal block, a first detection module and a second detection module; the terminal board is provided with a high-impedance differential amplifying circuit, an excitation power supply redundant output circuit, a power supply redundant circuit and a switching value position signal redundant output circuit; in practical application, the first detection module and the second detection module are respectively and fixedly arranged on the first detection plate and the second detection plate with the interface terminals. The interface terminal is an anti-error plugging interface terminal, so that the connection is convenient, the error plugging is avoided, and the dual redundancy can be conveniently realized. When the first detection module and the second detection module are used, one detection board is a main detection board, and the other detection board is a standby detection board.
The first detection board is provided with a signal processing circuit, an excitation power circuit, a power conversion circuit, a central processing unit and a relay output circuit; the input end of the high-resistance state differential amplifying circuit is connected with the signal output end of the position sensor, the output end of the high-resistance state differential amplifying circuit is connected with the input end of the signal processing circuit, the output end of the central processing unit is connected with the input end of the excitation power supply redundant output circuit through the excitation power supply circuit, and the output end of the excitation power supply redundant output circuit is connected with the input end of the position sensor.
The control output end of the central processing unit is connected with the input end of the switching value redundancy circuit through the relay output circuit, and the switching value redundancy circuit is used for outputting a switching value position signal;
the input end of the power supply redundant circuit is connected with the power supply inlet wire, and the output end of the power supply redundant circuit is connected with the input end of the central processing unit through the power supply conversion circuit;
the second detection plate is the same as the first detection plate in structure, and the connection relation between the second detection plate and the terminal board is the same as that between the first detection plate and the terminal board.
The relay output circuit comprises seven switching value control circuits, namely one path of control excitation power output, one path of control power input, one path of control fault output and four paths of position signal switching value output. The central processing unit adopts DSP 28335.
The second detection board and the first detection board are arranged by adopting circuit boards in actual use, and are respectively marked with a 1# detection board and a 2# detection board which are two board cards with completely same software and hardware design. The device consists of a sensor excitation power supply circuit, a position signal processing circuit, a digital signal processing chip (DSP 28335), a processor peripheral auxiliary circuit and a relay output circuit. The system is responsible for signal acquisition, position judgment and logic control of the whole system (the position judgment is the prior art and is not the invention point of the invention, so the description is not repeated here), the two board cards are redundant with each other, and the reliability of the real system is improved.
The position sensor comprises a position sensor, a position sensor sensing coil, a position signal processing circuit, a DSP (digital signal processor), a sensor excitation power circuit, a position sensor sensing coil, a high-resistance differential amplifying circuit, a signal processing module, a DSP (digital signal processor), a signal processing module and a relay position signal output circuit, wherein the sensor excitation power circuit on the sensing board outputs an excitation power needed by the position sensor under the control of the DSP, the excitation power is output to a position sensor excitation coil on a terminal board through an excitation power redundancy output circuit, the position sensor sensing coil outputs a corresponding current signal, the current signal is converted into a voltage signal which can be directly processed by the sensing board on the terminal board and is respectively sent to a 1# sensing board and a 2# sensing board through a plug-in terminal 1 and a plug-in terminal 2, the voltage signal is converted into a 0 ~ 3V voltage signal by the position signal processing circuit and is sent to the DSP analog-to-digital conversion module, whether a measured object reaches the.
Different levels are set on the terminal board aiming at the master-slave selection pins corresponding to the two connectors of the first plug terminal and the second plug terminal, wherein the master-slave selection pin of the first plug terminal is connected with a logic low level, and the master-slave selection pin of the second plug terminal is suspended. The detection board inserted to the first dock terminal is selected as a master detection board, and the detection board inserted to the second dock terminal is selected as a slave detection board.
And the main detection board outputs a normal excitation power supply and performs complete logic operation and position output functions on the received signals under a normal working state. At the moment, the slave detection board is in a standby state, and whether the main detection board has faults or not is continuously detected through the fault input pin, wherein each detection period is 100 us. As shown in FIG. two; when the main detection board fails, the power supply of the main detection board is automatically disconnected (only the working power supply of the processor is reserved), and the slave detection board immediately starts to work. The position sensor excitation power supply is output from the detection board under the control of the DSP, the position sensor induction coil outputs corresponding current signals, and the corresponding current signals are converted into corresponding voltage signals on the port board through a high internal resistance differential circuit and are respectively sent to a 1# detection board and a 2# detection board; convert analog voltage signal to digital signal through DSP analog-to-digital conversion module, judge through computational analysis whether the measured object reachs this position to the actuation of control relay, output position signal, it is specific:
different circuits are arranged on the terminal board aiming at the plug-in terminal of the No. 1 board card and the plug-in terminal of the No. 2 board card, the master-slave selection pins corresponding to the two connectors are connected with a logic low level, and the master-slave selection pins of the plug-in terminal of the No. 1 board card are suspended. The 1# integrated circuit board is the mainboard, and the 2# integrated circuit board is the slave plate. When the self-checking has no fault after the mainboard is electrified, K1.3 is attracted, and the slave board is kept in a standby state.
Under normal working condition, a sensor excitation power supply circuit on a detection plate outputs an alternating current excitation power supply required by a position sensor under the control of a DSP, the excitation power supply passes through an excitation power supply redundant output circuit on a terminal board and is output to a position sensor excitation coil, a position sensor induction coil outputs a corresponding current signal, the current signal is converted into a voltage signal on a port board through a high-resistance state differential amplification circuit and is respectively sent to a 1# detection plate and a 2# detection plate through a plug-in terminal, the detection plate converts the alternating current voltage signal into a direct current voltage signal of 0 ~ 3V through a position signal processing circuit and transmits the signal to DSP analog-to-digital conversion modules of two plate cards, the analog voltage signal is converted into a digital signal, whether a measured object reaches the position is judged through calculation and analysis, so that the pull-in of a relay is controlled through a relay output circuit to convert the position signal into a switching value signal, and relay contacts of the 1# detection plate (K1.4-K1.7) and the 2# detection plate (K2.4-K2.7) are respectively connected in parallel through a switching.
And the main detection board outputs a normal excitation power supply and performs complete logic operation and position output functions on the received signals under a normal working state. At the moment, the slave detection board is in a standby state, whether the main detection board breaks down or not is continuously detected by detecting whether K1.3 is sucked or not, and each detection period is 100us as shown in a second drawing; when the main detection board is in fault, the actuation K1.3 outputs an alarm signal, and the actuation K1.1 disconnects the main board excitation power circuit; and the slave board starts to work immediately after the detection board detects that the K1.3 is disconnected, and the attraction K2.1 is connected with the slave board excitation power circuit to ensure the normal working state.
The invention has wide trial range: the direct-current resistance of the coil of the electromagnetic position sensor is different at different temperatures, and the DSP calculates the ambient temperature of the position sensor through the relation between the voltage and the current applied to the exciting coil, so that the position sensor can be reliably used in a wider temperature range through temperature correction.
The invention has wide trial range: the direct-current resistance of the coil of the electromagnetic position sensor is different at different temperatures, and the DSP calculates the ambient temperature of the position sensor through the relation between the voltage and the current applied to the exciting coil, so that the position sensor can be reliably used in a wider temperature range through temperature correction.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (7)
1. Double redundancy discrete type induction position sensor signal intelligent acquisition and processing apparatus, its characterized in that: the detection device comprises a terminal board, a first detection module and a second detection module; the terminal board is provided with a high-impedance differential amplifying circuit, an excitation power supply redundant output circuit, a power supply redundant circuit and a switching value position signal redundant output circuit;
the first detection module is provided with a signal processing circuit, an excitation power circuit, a power conversion circuit, a central processing unit and a relay output end circuit; the input end of the high-resistance state differential amplifying circuit is connected with the signal output end of the position sensor, the output end of the high-resistance state differential amplifying circuit is connected with the input end of the signal processing circuit, the output end of the central processing unit is connected with the input end of the excitation power supply redundant output circuit through the excitation power supply circuit, and the output end of the excitation power supply redundant output circuit is connected with the input end of the position sensor;
the control output end of the central processing unit is connected with the input end of the switching value redundancy circuit through the relay output circuit, and the switching value redundancy circuit is used for outputting a switching value position signal;
the input end of the power supply redundant circuit is connected with the power supply inlet wire, and the output end of the power supply redundant circuit is connected with the input end of the central processing unit through the power supply conversion circuit;
the second detection module and the first detection module have the same structure, and the connection relationship between the second detection module and the terminal board is the same as that between the first detection module and the terminal board.
2. The dual redundant discrete inductive position sensor signal intelligent acquisition and processing device of claim 1, wherein: the relay output circuit comprises seven switching value control circuits, namely one path of control excitation power output, one path of control power input, one path of control fault output and four paths of position signal switching value output.
3. The dual redundant discrete inductive position sensor signal intelligent acquisition and processing device of claim 1, wherein: the central processing unit is the DSP28335 and its auxiliary peripheral circuits.
4. The dual-redundancy discrete inductive position sensor signal intelligent acquisition and processing device as claimed in claim 1, wherein the signal processing circuit is used for converting the alternating voltage signal into a voltage signal of 0 ~ 3V and transmitting the voltage signal to the DSP analog-to-digital conversion module to convert the analog voltage signal into a digital signal.
5. The dual redundant discrete inductive position sensor signal intelligent acquisition and processing device of claim 1, wherein: the first detection module and the second detection module are respectively and fixedly arranged on the first detection plate and the second detection plate with the interface terminals.
6. The dual redundant discrete inductive position sensor signal intelligent acquisition and processing device of claim 1, wherein: the interface terminal is an anti-error plugging interface terminal.
7. The dual redundant discrete inductive position sensor signal intelligent acquisition and processing device of claim 1, wherein: the output signal of the position sensor is converted into a corresponding voltage signal through a high internal resistance differential circuit, and the analog voltage signal is converted into a digital signal through a DSP analog-to-digital conversion module for processing.
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| CN201911088023.1A CN110687856B (en) | 2019-11-08 | 2019-11-08 | Dual-redundancy discrete type sensing position sensor signal intelligent acquisition and processing device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111739669A (en) * | 2020-07-24 | 2020-10-02 | 中国核动力研究设计院 | Redundant excitation structure, system and method suitable for rod position detector of nuclear power station |
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| CN106444354A (en) * | 2015-08-11 | 2017-02-22 | 南京理工大学 | Double-CPU redundant controller |
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| CN210924245U (en) * | 2019-11-08 | 2020-07-03 | 卧龙电气南阳防爆集团股份有限公司 | Dual-redundancy discrete inductive position sensor signal intelligent acquisition and processing device |
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2019
- 2019-11-08 CN CN201911088023.1A patent/CN110687856B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4528458A (en) * | 1984-01-06 | 1985-07-09 | Ncr Corporation | Self-diagnostic redundant modular power supply |
| CN106321819A (en) * | 2015-06-25 | 2017-01-11 | 泰科电子(上海)有限公司 | Position sensor and position sensing system |
| CN106444354A (en) * | 2015-08-11 | 2017-02-22 | 南京理工大学 | Double-CPU redundant controller |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111739669A (en) * | 2020-07-24 | 2020-10-02 | 中国核动力研究设计院 | Redundant excitation structure, system and method suitable for rod position detector of nuclear power station |
| CN111739669B (en) * | 2020-07-24 | 2022-02-01 | 中国核动力研究设计院 | Redundant excitation structure, system and method suitable for rod position detector of nuclear power station |
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