CN1164705A - On-Line Condition Monitoring and Fault Diagnosis System for Large Rotating Units - Google Patents

Abstract

On-line status monitoring and fault diagnosis system for large rotating units, including a preprocessing board connected to key phase signals and fast-changing signals; an intelligent key phase board controlling the sampling of the entire cycle and a high-speed data acquisition board for collecting vibration signals; The low-speed data acquisition board and the acquisition board for monitoring the switch signal are connected with the lower computer. The lower computer is responsible for real-time data collection and monitoring of the operating status of the unit through the high-speed and intelligent monitoring system, and the upper computer is responsible for online signal processing and fault diagnosis, and the network card is used to realize high-speed communication between them. It can collect, monitor and troubleshoot the vibration, displacement and temperature of the unit, process parameters and switch signals.

Description

On-Line Condition Monitoring and Fault Diagnosis System for Large Rotating Units

The invention relates to an on-line state monitoring and fault diagnosis system of a large rotating unit.

With the rapid development of modern science and technology, various types of rotating units (such as steam turbines, generators, blowers, compressors, etc.) are becoming larger, faster and more complex, and the mechanical efficiency and automation level of the units have been greatly improved. . If an accident occurs during the operation of these equipment, not only the expensive equipment itself will cause losses, but also the continuous mass production will be interrupted, which will bring huge economic losses and bad social impact. If the vibration, temperature, pressure and other operating conditions of large rotating units are monitored and diagnosed online, such serious consequences will be avoided or reduced.

For large rotating units, traditional secondary instrument monitoring can no longer meet the needs of reality. From the end of the 1960s, foreign countries began to use computers to study the condition monitoring and fault diagnosis of large-scale units, and developed such as the DDM system and ADRE system of the US BN company; the TEM system of the British Central Power Generation Department: the MHMS system of Japan's Mitsubishi Corporation And the MDC system of Westinghouse Corporation of the United States. my country also began to develop and research in the 1980s. Harbin Institute of Technology proposed fuzzy mathematics theory to implement unit vibration analysis and fault diagnosis, and developed the MMMD system; Xi'an Jiaotong University developed the RMMDS system. However, in the monitoring system for a single unit, most of them use a single computer plus some data acquisition function blocks, front-end signal conditioning function blocks, digital input function blocks, and analog output function blocks, etc., and then cooperate with the monitoring software. To complete tasks such as data collection, data processing, data display and storage, data analysis and fault diagnosis of the operating status of the unit, the burden is already very heavy. Because for precision fault technology, a large amount of analysis and calculation is required to obtain a diagnosis result with a relatively high degree of confidence. Obviously, it is not appropriate to use a computer to complete such a heavy task. Under normal circumstances, only a preliminary analysis of the signal can be achieved, but for the situation where a large number of signals are required to be collected, the signal collection density can only be reduced, and the unit cannot be continuously monitored, and some important information may be lost. For online systems, its real-time performance is also reduced.

The purpose of the present invention is to design an upper and lower industrial control microcomputer system, in which high-speed communication is realized through a network card. Use the lower industrial control microcomputer to undertake the real-time data collection and monitoring of the operating status of the unit through the high-speed and intelligent monitoring system; use the upper industrial control microcomputer to be responsible for the online status monitoring and fault diagnosis system of the large rotating unit for online signal processing and fault diagnosis. 1. The system with parallel structure can solve the problems existing in the background technology.

The technical solution adopted by the present invention is that it includes a signal preprocessing board connected with 1 key-phase signal and 12 (expandable as required) fast-changing signals; the signal pre-processing board is respectively connected to the intelligent key phase Level data acquisition board; the intelligent key phase board is connected to the lower industrial control microcomputer and the first industrial level data acquisition board; Industrial-grade data acquisition board; 1-channel self-test signal connected to the first, second and third industrial-grade data acquisition board; switch signal acquisition board connected to 24-channel (expandable as required) switch signal ; The first, second, and third industrial-grade data acquisition boards and switch signal acquisition boards are respectively connected to the lower industrial control microcomputer; one end of the lower industrial control microcomputer is connected to the upper industrial control microcomputer through the first network card and the second network card, The other end is connected with the input and output device consisting of the first display, the first keyboard and the first mouse; one end of the upper industrial control microcomputer is connected with the digital signal processing and analysis system (DSP hardware), and the other end is connected with the second display, the second keyboard, A second mouse and printer constitute the input-output device connection.

Signal preprocessing board, which includes amplification and shaping circuit, AC and DC separation circuit, tracking filter circuit and amplification circuit, in which: the key phase signal on the rotating shaft passes through the adjustment circuit, DC blocking, comparison, amplification circuit, photoelectric isolation circuit and shaping circuit After the circuit is connected with the intelligent key phase plate; the vibration and displacement fast-changing signals generated by the eddy current sensors at each measuring point installed on the rotating unit, one way passes through the DC in the AC and DC separation circuit, the subtraction circuit, and the other through the AC After the subtraction circuit in the DC separation circuit, it is connected to the tracking filter circuit, and after the amplifying circuit is connected to the first industrial-grade data acquisition board; the pulse input terminal of the tracking filter circuit is connected to the programmable counter output terminal of the smart key phase board ;

Intelligent key-phase board, which includes parallel interface, single-chip microcomputer, program memory, first programmable counter, second programmable counter, wherein: the key-phase signal is connected to the single-chip microcomputer through the amplification and shaping circuit of the signal preprocessing board; The industrial computer is connected to the single-chip microcomputer through the parallel interface; the single-chip microcomputer is respectively connected to the program memory, the first programmable counter, and the second programmable counter, and the output of the first programmable counter is connected to the first industrial-grade data acquisition board, the second The output of the two programmable counters is connected to the tracking filter in the signal preprocessing board;

Digital signal acquisition board, which includes photoelectric isolation circuit, shaping circuit, peripheral circuit, single-chip microcomputer, parallel communication interface, in which: the switching signal passes through the photoelectric isolation circuit, then the shaping circuit, peripheral circuit, single-chip microcomputer, parallel communication port to connect with the lower industrial computer.

The entire monitoring and diagnosis system is composed of upper and lower industrial control microcomputers. The lower computer is responsible for real-time data collection and monitoring of the unit's operating status through the high-speed and intelligent monitoring system. The system also has a self-test function. The upper computer is responsible for the digital signal processing (DSP hardware) analysis system, online signal processing and fault diagnosis. The upper and lower industrial control microcomputers are responsible for division of labor and work in parallel. They realize high-speed communication through the network card. In order to obtain higher amplitude and phase accuracy in signal spectrum analysis, an intelligent detection and control system composed of single-chip microcomputers is designed for the state data acquisition front-end device of the lower computer to realize frequency conversion and full-cycle sampling. In order to improve the real-time performance of the system, a hardware digital signal processing DSP analysis system is established on the upper computer. The entire monitoring and diagnosis system can provide real, real-time on-site status data, online reliable analysis and comprehensive fault diagnosis results for monitoring the operation of the unit.

Compared with the background technology, the present invention has the beneficial effects that:

1. It solves the contradiction that a single machine is too heavy in multi-channel signal acquisition and analysis, and is more suitable for comprehensive online data acquisition and real-time status monitoring of the unit;

2. Realized the relatively independent and parallel work of data acquisition and real-time status monitoring, online dynamic signal analysis and fault diagnosis;

3. With the cooperation of the high-speed data acquisition board and the intelligent key phase board, 12 channels (or more channels) of vibration and displacement signals can be accurately collected at high speed and high speed data transmission with variable frequency and full cycle;

4. The conditioning of vibration and displacement signals adopts low-pass tracking filtering composed of advanced switched capacitor filters, which avoids the phenomenon of spectrum aliasing;

5. The system can automatically switch various collection methods, and has the function of "black box";

6. The system adopts IPC and industrial grade data acquisition board, which effectively guarantees the reliability of the system and greatly improves the performance of the system;

7. Modular design is adopted, and the system software and hardware functions can be easily expanded.

Therefore, it is very suitable for all kinds of large-scale rotating units such as steam turbines, generators, blowers, compressors and other equipment, to realize the acquisition of vibration, displacement fast-changing signals and temperature, pressure and process parameters and other slow-changing signals and switching signals. Monitoring and comprehensive fault diagnosis.

Description of drawings:

Fig. 1, overall circuit structure block diagram of the present invention;

Fig. 2. Circuit structure diagram of the signal preprocessing board;

Figure 3, the block diagram of the circuit structure of the smart key phase board;

Figure 4. Circuit structure diagram of switch signal acquisition board;

Fig. 5, the key phase signal conditioning circuit diagram in the signal preprocessing board circuit;

Fig. 6, the vibration signal conditioning circuit diagram in the signal preprocessing board circuit;

Figure 7. Schematic diagram of the circuit structure of the smart key phase board;

Figure 8. Schematic diagram of the circuit structure of the switch signal acquisition board.

The details of the present invention are given below by describing the embodiments in conjunction with the accompanying drawings.

As shown in Fig. 1 and Fig. 2, the one-way key phase signal 1 on the rotating shaft passes through the adjustment circuit 2a ₁ in the signal preprocessing board 2, the DC blocking, comparison, and amplification circuit 2a ₂ , the photoelectric isolation circuit 2a ₃ , and the shaping circuit After 2a ₄ , it is input to the intelligent key phase board 3; the 12-way vibration and displacement fast-changing signals generated by the eddy current sensors installed at each measuring point on the rotating unit pass through the DC circuit 2b ₁ and the AC, AC, and subtraction circuits 2b ₂ DC separation circuit 2b, tracking filter circuit 2c, and amplifier circuit 2d are input to PCL-1800 industrial grade data acquisition board 8, and tracking filter circuit 2c is also connected with programmable counter 3e of smart key phase board 3. As shown in Figure 2 and Figure 3, the key phase signal 1 is connected to the 8098 single-chip microcomputer 3b through the amplification and shaping circuit 2a of the signal preprocessing board 2; The counter 3e is connected, the output of the 8253 programmable counter 3d is connected to the PCL-1800 industrial grade data acquisition board 8, and the output of the programmable counter 3e is connected to the tracking filter circuit 2c in the signal preprocessing board 2. As shown in Figure 1, the slowly changing signal 5 (12 channels for vibration peak value, 17 channels for bearing temperature, and 17 channels for process parameters) is connected to PCL-813 industrial data acquisition board 9 and PCL-813 industrial data acquisition board 10; 1 channel for self-inspection Signal 6 is connected with data acquisition boards 8, 9, 10 respectively. As shown in Fig. 1 and Fig. 4, 24 switching signal acquisition boards 11 composed of a photoelectric isolation circuit 11a, a shaping circuit 11b, a peripheral circuit 11c, an 8098 single-chip microcomputer 11d, and a parallel communication interface 11e are connected to the lower The industrial computer 20 is connected. As shown in Figure 1, the data acquisition boards 8, 9, 10 and the switching signal acquisition board 11 are respectively connected to the lower industrial computer 20 through the network card 19 (NE2000), and the network card 20 (NE2000) is connected to the upper industrial computer 13 (486D × 166 memory : 8MB HDD: 540MB) is connected, and the other end is connected with the input and output equipment that is made up of display 21, keyboard 22 and mouse 23; One end of host industrial computer 13 is connected with hardware digital signal processing DSP analysis system 12, and the other end is connected with display 14, The input and output devices composed of keyboard 15, mouse 16 and printer 17 are connected.

As shown in Figure 5, an integrated operational amplifier U4: LF347 is used in the processing of the key-phase signal. One key phase signal 1 on the rotating shaft is input from pin 3 of the integrated operational amplifier U4:A of LF347, and output from pin 1 of U4:A after being buffered by U4:A, and after DC blocking and filtering by capacitor C4 and resistor R25, Input from pin 5 of U4:B in the amplifying circuit composed of U4:B and resistors R26 and R27, and output from pin 7 of U4:B after amplification, and then from U4:C and resistors R28, R29 and potentiometer U4 in the comparison circuit composed of W4: C’s 9-pin input and 8-pin output, at this time the signal is processed into a square wave, then amplified by the triode T1 and output by the resistor R30, from the photoelectric isolation chip TIP127 and resistors R31, R32 The 3-pin input of the photoelectric isolation chip in the formed photoelectric isolation circuit is output by the 5-pin, and then connected with the smart key phase board 3 after being shaped by two 74LS14 inverters U5:A. As shown in Figure 6, the signal preprocessing board preprocesses 12 channels of vibration and displacement signals. During the processing, three pieces of LF347 operational amplifiers U1, U3 and one piece of MF10 low-pass tracking filter U2 are used. Installed on the rotating unit, the 12 channels of vibration and displacement fast-changing signals 4 generated by eddy current sensors at each measuring point (take one channel as an example) are input from LF347 integrated operational amplifier U1: pin 3 of A is buffered and output from pin 1, and then divided into two channels , all the way through the resistor R2 into the DC composed of capacitors C1, C2, resistors R5, R3, R4 and U1: B through the circuit and output from pin 7 of U1: B, the output DC component is divided into two channels, one of which is connected to U1: A The other output signal of one foot of U1 enters the subtraction circuit composed of resistors R1, R10, R8, R9 and U1: C, and is output from U1: C foot 8; the other output signal of U1: B's 7 foot output passes through Resistor R7 enters the amplifying circuit composed of U1: D, U3: A, resistors R6, R16, R17, R15 and potentiometers W1, W2, and outputs from U3: pin 1 of the circuit; U1: pin 8 of C The output AC component is input from pin 5 of U2 of the low-pass tracking filter circuit composed of a low-pass tracking filter U2, resistors R11, R12, R13, and R14, and the clock pulse of the filter is input from pins 10 and 11 of U2. Input, the signal is filtered and output from pin 20 of U2, and then input from pin 5 of U3:B in the amplification circuit composed of U3: B, resistors R19, R18, and potentiometer W3. This AC signal is amplified and communicated with U3 : The DC components output by pin 1 of A are superimposed by resistors R21 and R20 as AC and DC components respectively, and then amplified from the amplifying circuit composed of U3:C, U3:D and resistors R23 and R22, and then from U3:C The 9-pin input is amplified and output from the 14-pin of U3:D. At this time, the vibration and displacement signals have been processed and sent to the PCL-1800 industrial-grade data acquisition board 8.

As shown in Figure 7, the HSIO port of the 8098 single-chip microcomputer 3b is connected to the key phase signal 1 after being amplified and shaped by the shaping circuit 2a, and the 8-bit data bus DB of the single-chip microcomputer 3b is connected to the data line of the EPROM2764 program memory 3c, and the 8253 programmable counter 3d, The A port of the data line of the 8253 programmable counter 3e is connected to the data bus of the 8255-1 programmable parallel interface chip. The AD0～AD7 data/address lines of the single-chip microcomputer 3b are connected with the low 8-bit address lines of the program memory 3c after passing through the 74LS373 latch, and the address lines A8～A12 of the single-chip microcomputer 3b are directly connected with the address lines A8～A12 of the program memory 3c, Form 13-bit address line, A13～A15 of MCU 3b are respectively connected to A, B, C terminals of 74LS138-1 decoder to form address decoding, its output Y1 is connected to CE terminal of program memory 3C (address is 2000H), Y2 is connected to CS terminal of programmable counter 3d (address is 4000H), Y3 is connected to CS terminal of programmable counter 3e (address is 6000H), Y4 is connected to CS terminal of 8255-1 programmable parallel interface chip (address is 800 0H), Y5 is connected to The E terminal of the 74LS2458 bus transceiver (address is A000H), the A, B, and C ports of 8255-1 and 8255-2 are connected to each other, and the data lines of 8255-2 and 8255-3 are connected with the data lines of the lower computer 20 AJ bus , Port A of 8255-3 is connected to Port B of the eight-bus transceiver, and PC7 of 8255-3 is connected to HI2/04 of the single-chip microcomputer 3b, which is used to transmit the command word to send an interrupt request to the single-chip microcomputer 3b. After the lower computer 20 AJ bus address line is decoded by the decoding circuit composed of 74LS138-2, NAND gate 74LS08 and 74LS14 NOT gate, the Y4 terminal of 74LS138-2 is connected to the CS terminal of 8255-3 (I/O address is 360H) , Y5 is connected to the CS end of 8255-2 (the I/O address is 368H).

The work of intelligent key-phase board 3 is carried out under the control of the supervisory program that is stored in the program memory 3C, key-phase signal 1 is introduced from the HSIO port of single-chip microcomputer 3b, whenever key-phase signal pulse rising edge arrives, to single-chip microcomputer 3b Send an interrupt request, and record the current value of the on-chip timer after responding to the interrupt. When the next key phase pulse arrives, record the overflow times of the timer, and calculate the current speed of the rotor through software calculation. The rotation speed value is then multiplied by a coefficient and written into two programmable counters 3d and 3e. The two programmable counters 3d and 3e control the frequency of pulses according to the written values, and they respectively generate PCL-1800 The external trigger pulse of the industrial-grade data acquisition board and the clock pulse of the low-pass tracking filter 2c. Simultaneously, the single-chip microcomputer 3b writes the rotating speed and the status word of mechanical operation together into the 8255-1 programmable parallel interface chip. After buffering by the 8255-2, the lower computer 20 can issue commands to the smart key phase board through the 8255-3 to control the smart key. The way the phase plate works is controlled. The 74LS138-1 decoder is used for address decoding in the smart key phase board, and the 74LS138-2 is used for port address decoding of the lower computer 20 . The smart key phase board is intelligently controlled by a single-chip microcomputer, with functions such as speed measurement control, full-cycle sampling control, trigger tracking filter, intelligent control acquisition mode, etc. Its function enhances the monitoring function, greatly reduces the workload of the lower computer, and improves the system's response speed.

As shown in Figure 8, the switching signal 7 is photoelectrically isolated by the photoelectric isolation circuit 11a composed of the TLP521 photoelectric isolation chip, and after being shaped by a 74LS14 non-gate circuit 11b, 24 channels are simultaneously connected to the 8255-1 programmable parallel interface chip. A, B, C port, the 8-bit data bus of 8098 single-chip microcomputer 11d is connected with the data line of EPROM2764 program memory, the data line of 8255-1, 8255-2 programmable parallel interface chips, and the data/address bus AD0 of single-chip microcomputer 11d ～AD7 is locked by 74LS373 latch, and connected with the low 8-bit address line of EPROM2764, A8～A12 of EPROM2764 is connected with A8～A12 of the 11d address line of the single-chip microcomputer, forming the 13-bit address line of EPROM2764, the address of the single-chip microcomputer 11d Lines A13-A15 are respectively connected to terminals A, B and C of the 74LS138-1 decoder. After decoding, Y1 is connected to the CE terminal of EPROM2764 (the address is 2000H), and Y2 is connected to the CS terminal of 8255-1 ( The address is 4000H), Y3 is connected to the CS terminal of 8255-2 (address is 6000H); A, B, and C ports of 8255-2 and 8355-3 are respectively connected to form a data buffer, and the data line of 8255-3 is connected to the lower computer 20AJ The data line connection of the bus is used for the parallel communication between the lower computer 20 and the switch signal monitoring board. After the address of the lower computer 20 AJ bus is decoded by the decoding circuit composed of 74LS138-2 and 74LS08 programmable parallel interface, the Y4 terminal of 74LS138-2 is connected to the CS terminal of 8255-3 (I/O address is 2E0H).

The switching value signal acquisition board is composed of an 8098 single-chip microcomputer system, which monitors the relay contacts. If any switch signal jumps, it will send an interrupt to the 8098. The 8098 records the status of each relay and transmits it to the main control microcomputer through the parallel interface. The main control microcomputer sends an interrupt, so that the system enters the "black box" high-speed acquisition state.

The upper computer 13 and the lower computer 20 are connected through two Novell Netware Lite 2000 network cards to carry out point-to-point data communication. Since the RAMDRIVE technology is used in the lower computer to map the memory into a file system, the shared file service provided by Novell Netware and MS can be used. -The support for shared files provided by DOS is designed to use the extended memory function. Add the virtual disk to the network as a network disk, and map it to a logical partition of the hard disk of the data processing computer, and the two computers can realize data communication. Using this method for communication not only has high speed and good reliability, but also reduces software programming work Quantity, installation and use are very convenient.

Claims (3)

1. An online condition monitoring and fault diagnosis system for a large rotating unit, characterized in that it includes: 1) A signal preprocessing board [2] connected to 1 key-phase signal [1] and 12 fast-changing signals [4]; 2) The signal preprocessing board [2] is respectively connected to the smart key phase board [3] and the first industrial-grade data acquisition board [8]; 3) The smart key phase board [3] is respectively connected to the lower industrial control microcomputer [20] and the first industrial grade data acquisition board [8]; 4) The second industrial-grade data acquisition board [9] and the third industrial-grade data acquisition board [10] connected to the 46-way slowly changing signal [5]; 5) One channel of self-test signal [6] is respectively connected with the first block [8], the second block [9] and the third block [10] of industrial grade data acquisition board; 6) A switch signal acquisition board [11] connected with 24 switch signals [7]; 7) The first block [8], the second block [9], the third block [10] industrial-grade data acquisition board and switch signal acquisition board [11] are respectively connected with the lower industrial control microcomputer [20]; 8) One end of the lower industrial control microcomputer [20] is connected with the upper industrial control microcomputer [13] through the first network card [19] and the second network card [18], and the other end is connected with the first display [21], the first keyboard [22] ] and the input-output device that the first mouse [23] is formed is connected; 9) One end of the upper industrial control microcomputer [13] is connected with the hardware digital signal processing and analysis system (DSP) [12], and the other end is connected with the second display [14], the second keyboard [15], the second mouse [16] and the printer [17] Composed of input and output device connections. 2. The online condition monitoring and fault diagnosis system for large rotating units according to claim 1, characterized in that: 1). Signal preprocessing board [2], which includes amplification and shaping circuit [2a], AC and DC separation circuit [2b], tracking filter circuit [2c] and amplification circuit [2d], wherein: a. The key phase signal [1] on the rotating shaft passes through the adjustment circuit [2a ₁ ], the DC blocking, comparison, and amplification circuit [2a ₂ ], the photoelectric isolation circuit [2a ₃ ] and the shaping circuit [2a ₄ ], and then connects with the smart key Phase plate [3] connection; b. The vibration and displacement fast-changing signals [4] generated by the eddy current sensors at each measuring point installed on the rotating unit pass through the DC circuit [2b ₁ ] in the AC and DC separation circuit [2b], and the subtraction circuit [2b ₂ ], the other way passes through the subtraction circuit [2b ₂ ] in the AC-DC separation circuit [2b], and then connects to the tracking filter circuit [2c], and after the amplification circuit [2d], it is connected to the first industrial-grade data acquisition board [8 ] connection, the pulse input terminal of the tracking filter circuit [2c] is connected with the programmable counter [3e] output terminal of the smart key phase board [3]; 2) intelligent key phase plate [3], it comprises parallel interface [3a], single-chip microcomputer [3b], program memory [3c], the first programmable counter [3d], the second programmable counter [3e], wherein : a. The key phase signal [1] is connected with the single-chip microcomputer [3b] through the amplification and shaping circuit [2a] of the signal preprocessing board [2]; b. The lower industrial computer [20] is connected with the single-chip microcomputer [3b] through the parallel interface [3a]; c. The single-chip microcomputer [3b] is respectively connected with the program memory [3c], the first programmable counter [3d], and the second programmable counter [3e], and the output of the first programmable counter is connected with the first industrial grade data acquisition Plate [8], the tracking filter circuit [2c] in the output connection signal preprocessing board [2] of the second programmable device counter [3e]; 3) switch signal acquisition board [11], which includes photoelectric isolation circuit [11a], shaping circuit [11b], peripheral circuit [11c], single-chip microcomputer [11d], parallel communication interface [11e], wherein: switch value Signal [7] passes through photoelectric isolation circuit [11a], then through shaping circuit [11b], peripheral circuit [11c], single-chip microcomputer [11d], parallel communication interface [11e], is connected with lower industrial computer [20]. 3. The online condition monitoring and fault diagnosis system for large rotating units according to claim 2, characterized in that: 1) Signal preprocessing board [2]: a. The 1-way key-phase signal on the rotating shaft [1] is input from the 3-pin of the LF347 integrated operational amplifier U4:A, and output from the 1-pin of U4:A after buffering, and is directly blocked by the capacitor C4 and the resistor R25, and then from U4 U4 in the amplifying circuit composed of B and resistors R26, R27: input from pin 5 of B, after amplified, output from pin 7 of U4: B, and then from U4: C, resistors R28, R29 and potentiometer W4 U4 in the comparison circuit: C’s 9-pin input and 8-pin output. At this time, the signal is processed into a square wave, and then amplified by the triode T1 and then output by the resistor R30. The 3-pin input of the photoelectric isolation chip in isolation is output by 5-pin, and then connected to the smart key phase board [3] after being shaped by two 74LS14 inverters U5:A and U5:B; b. Installed at each measuring point on the rotating unit, 12 channels of vibration and displacement fast-changing signals [4] (taking one channel as an example) generated by the eddy current sensor are introduced from the resistor R24, and the high-frequency signals are filtered out after passing through the capacitor C3 , input from pin 3 of LF347 integrated operational amplifier U1: A, output from pin 1 after being buffered, and then divide into two channels, one through resistor R2, and enter the DC passing circuit composed of capacitors C1, C2, resistors R5, R3, R4 and U1: B , output from pin 7 of U1:B, the output DC component is divided into two paths, one of which enters the subtraction composed of resistors R1, R10, R8, R9 and U1:C together with the other output signal of pin 1 of U1:A The circuit is output from U1: pin 8 of C, another output signal of pin 7 of U1: B enters through resistor R7, and is composed of U1: D, U3: A, resistors R6, R16, R17, R15 and potentiometers W1, W2 The amplifying circuit composed of U3: the 1-pin output of A of the circuit, and the AC component output from U1: the 8-pin output of C are from the low-pass tracking composed of a low-pass tracking filter U2, resistors R11, R12, R13, and R14. The 5-pin input of the filter circuit, and the clock pulse of the filter is input by the 10-pin and 11-pin of U2, and the signal is filtered by the 20-pin output of U2, and then composed of U3: B, resistors R19, R18, and potentiometer W3 In the amplification circuit of U3: B’s 5-pin input, this AC signal is amplified and U3: A’s 1-pin’s output DC component, respectively through the resistors R21 and R20 with AC and DC components superimposed, together from U3: C, U3:D and resistors R23, R22 are amplified by the amplification circuit, input from pin 9 of U3:C, and output from pin 14 of U3:D to PCL-1800 industrial grade data acquisition board 8 after amplification; 2) Smart key phase board [3]: The HSIO port of the 8098 single-chip microcomputer [3b] is connected to the key-phase signal [1] after being amplified and shaped by the shaping circuit [2a]. The A port of the data line of the programming counter [3d], 8253 programmable counter [3e], the data bus connection of the 8255-1 programmable parallel interface chip, the AD0~AD7 data/address line of the single chip microcomputer [3b] through the 74LS373 latch Afterwards, it is connected with the low 8-bit address lines of the program memory [3c], and the address lines A8～A12 of the single-chip microcomputer [3b] are directly connected with the address lines A8～A12 of the program memory [3c] to form 13 address lines, and the single-chip microcomputer [3b] ]’s A13~A15 are respectively connected to the A, B, and C terminals of the 74LS138-1 decoder to form address decoding, and its output Y1 is connected to the CE terminal of the program memory [3C], and Y2 is connected to the CS terminal of the programmable counter [3d]. Y3 is connected to the CS terminal of the programmable counter [3e], Y4 is connected to the CS terminal of the 8255-1 programmable parallel interface chip, Y5 is connected to the E terminal of the 74LS245 eight-bus transceiver, and A, B, and C of the 8255-1 and 8255-2 The ports of 8255-2 and 8255-3 are connected to each other, the data lines of 8255-2 and 8255-3 are connected to the data lines of the AJ bus of the lower computer [20], the A port of 8255-3 is connected to the B port of the eight-bus transceiver, and the PC7 of 8255-3 is connected to the single-chip microcomputer The H12/04 connection of [3b], after the address line of the lower computer [20] AJ bus is decoded by the decoding circuit composed of 74LS138-2, NAND gate 74LS08 and 74LS14 NOT gate, Y4 terminal of 74LS138-2 is connected to 8255- 3's CS terminal, Y5 is connected to the CS terminal of 8255-2; 3) Switch signal acquisition board [11]: The switching signal [7] is photoelectrically isolated by the photoelectric isolation circuit [11a] composed of the TLP521 photoelectric isolation chip, and after being shaped by a 74LS14 NOT gate circuit [11b], 24 channels are connected to the 8255-1 programmable parallel interface chip at the same time. Ports A, B, and C, the 8-bit data bus of the 8098 single-chip microcomputer [11d] are connected with the data lines of the EPROM2764 program memory, the data lines of the 8255-1, 8255-2 programmable parallel interface chips, and the data of the single-chip microcomputer [11d] /Address bus AD0～AD7 is connected with the low 8-bit address line of EPROM2764 after being latched by the 74LS373 latch, and A8～A12 of EPROM2764 is connected with A8～A12 of the single-chip microcomputer [11d] address line to form a 13-bit address line of EPROM2764 , single-chip microcomputer [11d] address lines A13 ~ A15 are respectively connected to the A, B, C terminals of the 74LS138-1 decoder, after decoding, its Y1 is connected to the CE terminal of the EPROM2764, and Y2 is connected to the CS terminal of the 8255-1 Terminal connection, Y3 is connected with the CS terminal of 8255-2, A, B, and C ports of 8255-2 and 8355-3 are respectively connected to form a data buffer, and the data line of 8255-3 is connected with the data line of the AJ bus of the lower computer [20] Connection, used for the parallel communication between the lower computer [20] and the switch signal monitoring board. After the address of the lower computer [20] AJ bus is decoded by the decoding circuit composed of 74LS138-2 and 74LS08 programmable parallel interface, the Y4 terminal of 74LS138-2 is connected to the CS terminal of 8255-3.

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