Microelectronics paper on the application of microcomputer monitoring technology in railway equipment failure analysis
1. Current situation and development of railways:
Railways Due to the innate comprehensive advantages of all-weather, small land occupation, large transportation volume, low energy consumption, fast speed, good safety and high cost performance, it will inevitably become the backbone of the country's comprehensive transportation system. Since 2008, China's railways have entered the era of high-speed railways. Communication signals are an important part of the four core technologies of high-speed railways and are directly related to the construction and safe operation of high-speed railways. With the rise of high-speed railways, new and higher requirements have been put forward in terms of safety and functionality of railway communication signals.
2. Introduction to microcomputer monitoring:
The railway signal microcomputer monitoring system is a dedicated railway signal microcomputer monitoring equipment and an important tool for electrical maintenance and management. The signal microcomputer monitoring system utilizes the high-speed information processing capabilities of computers to achieve uninterrupted, comprehensive and automatic real-time monitoring of signal equipment. It can obtain complete and continuous real-time data, avoid interference and influence of human factors, improve the quality of signal equipment management, and prevent hidden accidents. At the same time, the large amount of on-site data recorded by this equipment is of great help in analyzing the causes of accidents and understanding the status of the equipment.
3. Basic functions of microcomputer monitoring:
3.1 Information collection
Main monitoring objects of the microcomputer monitoring system:
3.1.1 External power grid Monitoring;
External power grid input phase voltage, line voltage, current, frequency, phase angle, and power.
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3.1.2 Power supply screen output monitoring:
Power supply screen output voltage, current, frequency, power; 25Hz power supply output voltage phase angle; intelligent power supply The screen is connected through the interface.
Monitoring accuracy: power supply voltage: ±1%; current: ±2%; frequency: ±0.5Hz; phase angle ±1%; power: ±1%
3.1. 3 Track circuit monitoring: n
AC continuous track circuit monitoring; track relay AC voltage, DC voltage; 25Hz phase-sensitive track circuit monitoring; track receiving end AC voltage, phase angle; hump 2.3 track circuit monitoring; Hump ??JWXC-2.3 track relay operating current;
Monitoring accuracy: voltage: ±1%; current: ±3%; phase angle: ±1%
3.1.4 Switch machine Monitoring:
DC switch machine monitoring; switch machine operating current, fault current, and operating time during the switch conversion process; AC switch machine monitoring; switch machine operating current, power, and operating time during the switch conversion process. Camelback ZD7 type DC fast switch machine; switch machine operating current, fault current and operating time during the switch switching process.
3.1.5 Turnout indicates voltage monitoring:
Turnout indicates AC and DC voltage;
Monitoring accuracy: current: ±2%, time ≤0.1S; Voltage: ±1%; Power: ±2%
3.1.6 Signal monitoring:
Monitoring of train signal lighting circuit current; train signal filament relay (DJ, 2DJ) working AC current. n
Monitoring accuracy: voltage ±1%; current: ±2%
3.1.7 Insulation leakage current monitoring
3.1.8 Cable insulation monitoring: < /p>
The core wire of the cable is insulated from the ground throughout; the leakage current of the power supply to the ground is monitored; the leakage current of the output power supply to the ground is monitored.
Monitoring accuracy: insulation, leakage current: ±10%
3.1.9 In-station coded monitoring: In-station sending box power output voltage, sending current, carrier frequency and low frequency.
3.1.10 Centralized insulated frequency shift automatic blocking monitoring:
Transmitting end output voltage, transmitting current, carrier frequency and low frequency frequency; receiving end limiting input voltage, frequency shifting frequency and low frequency.
Monitoring accuracy: voltage ±1%; current: ±2%, frequency: ±0.1Hz.
3.1.11 Centralized non-insulated frequency shift automatic blockage monitoring: n
The interval frequency shift transmitter sends voltage, current, carrier frequency and low frequency. Interval frequency shifting receiver rail-in, rail-out 1 (main rail), rail-out 2 (small rail) voltage, carrier frequency, and low frequency. Interval frequency-shifted cables simulate network cable side voltages.
Monitoring accuracy: voltage ±1%; current: ±2%, frequency: ±0.1Hz.
3.1.12 Semi-automatic blocked line voltage and current monitoring:
Monitoring accuracy: voltage ±1%; current: ±2%
3.1.13 Environmental status Analog quantity monitoring:
Ambient temperature in the signal machinery room, power screen room, computer room and TDCS vehicle terminal cabinet; civil air conditioner voltage, current, and power monitoring; key equipment Surface temperature monitoring:
Monitoring accuracy: temperature: ±1℃, humidity: ±3%RH, voltage: ±1%, current: ±2%, power: ±2%
3.1.14 Switch quantity monitoring function:
Button status, console display status, key relay status, etc.; monitor the broken filament status of the train signal main filament and alarm; n
Pair combination The main and auxiliary fuse switching devices on the zero floor, combination side and console are used to monitor, record and alarm; the switch machine display gap status is monitored, recorded and alarmed through the communication interface.
3.2 Station computer
The station computer is the core of the station microcomputer monitoring system. Its main functions are:
3.2.1 Display and storage:
Display and playback of station application status diagram. Station diagram can be enlarged, reduced and displayed in full screen.
Real-time status display of switch value and historical record query.
Real-time test forms, daily reports, daily curves, monthly curves, and annual trend lines of analog quantities.
Switch machine operating current curve.
Console button operation records, including train shunting, seal breaking button, fault notification button, etc.
The number of operations and timetable of key equipment, including the number of switch machine operations; the number of times the break button is used; the number of section occupancies; the number of times trains and shunting buttons are used; the number of fault notification buttons, trains, and shunting The number of times the bus signal is opened, etc.
Test tables and variation curves of cable insulation and power supply ground leakage current.
Track circuit shunt residual voltage report record.
3.2.2 Data processing and control
Import/export of configuration files and historical data.
Select multi-channel insulation for combined testing.
Management and export of playback files.
Print management and export of curves and various reports.
Authorized to modify baseline parameters and upper and lower alarm limits.
Transmit various real-time data to the upper network (server, terminal), including switching values, analog values, alarms, early warnings and various status and system information.
Receive and execute upper-layer commands, and transmit response data to the upper-layer network as needed.
3.2.3 Alarm and event management
Based on pre-defined logic, real-time alarms and early warnings at the first, second and third levels are realized.
Voice and sound and light alarm.
Query of alarm and early warning historical information.
Manual confirmation of important alarms.
Summary, statistics and analysis of equipment failures and alarms.
Records and historical queries of system operation events, user operation events, etc.
TDCS/CTC system working status record and fault alarm.
Train control center system working status records and fault alarms.
Computer interlocking working status records and fault alarms.
4. Analysis of specific fault conditions:
4.1 The switch cannot operate normally:
When it is judged that the switch should move but does not move or does not move in place ( Taking the action of the total setting button or the total reverse button as the entry point
), according to the working principle of the switch action circuit, determine the reason why the switch does not operate:
The switch section is locked Status; (according to red and white light strips and guide master lock conditions); 1DQJ does not pick up; 2DQJ does not rotate pole; switch action power supply failure; start fuse is broken; switch action circuit is open
4.2 Switch Break representation:
According to the measurement of the voltage indicated by the distribution board, the AC and DC components of the switch representation voltage can be obtained. When the switch is in the position or reverse position, and the switch indicates that the relay cannot be energized, it can be analyzed that the switch indicates the fault point in the circuit, such as indoor disconnection, outdoor disconnection, outdoor mixed wire, diode short circuit, relay disconnection, Capacitor disconnection, capacitor short circuit, indicating fuse blowout and other faults, guide the signal workers to deal with the fault.
4.3 The train signal cannot be opened normally:
If the white light strip does not appear, for the 6502 electrical centralized equipment, collect information based on the button indicator light and the arrangement entry indicator light, etc., and record the circuit The action program provides the judgment range of circuit faults through logical analysis. Mainly check whether the switch indicators on the approach are normal and whether the track circuit sections passed by the approach are occupied or locked (including inspection of over-limit insulation sections). If any abnormality is found in the above conditions, a report will be given. hint.
If the white light band has appeared but the signal cannot be opened, you need to check the following conditions:
For the pick-up signal and the main line departure signal, check to determine whether the signal machine is at a red light and has a broken wire. Status;
Use the start button indicator light and signal repeater light status to determine whether the train signal relay is excited or not self-closing. Provide fault diagnosis tips.
For departure signals, the light information can be expressed according to different blocking modes in the departure area (automatic blocking, semi-automatic blocking, inter-station contact, inter-field contact), check and determine whether the opening conditions of the signal are met, and give Judgment prompts.
4.4 Abnormal closure of train signal:
After the train signal is opened, it will be closed normally in the following three situations, and it will be closed abnormally in other situations.
The trains sequentially occupy the inner and outer sections of the signal; the signal is canceled; the signal is manually unlocked;
The monitoring system can check whether the switch indicators on the approach are normal and the tracks passed on the approach Check whether the circuit section is occupied or flashes a red light band momentarily (including inspection of over-limit insulation). If any abnormality in the above conditions is found, a prompt will be given. Check whether the signal is turned off due to allowing the light filament to be turned off twice; for the departure signal, you can also continuously monitor the interval occlusion status, interval contact, inspection and other conditions to determine whether the signal is abnormally shut down due to changes in these conditions.
4.5 Real-time analysis of track circuits:
Through automatic tracking of incoming trains, faulty track circuit shunts can be judged and alarmed when passing trains; at the same time, the track can be judged Whether the red light band of the circuit section is abnormal (normal occupancy or section failure). And by comparing and analyzing the AC and DC voltages at the receiving end of the track relay, the fault scope is determined.
For interval track circuits, create a summary report to centrally display the analog values ??at each point of the system test from the sending to the receiving loop. Use the test values ??at each intermediate point to point out the location of possible faults to facilitate maintenance. Personnel handles failures. The interface with other systems can obtain information from microcomputer interlocking, TDCS, train control, intelligent power screen, intelligent filament and other systems according to standard protocols. Information can also be provided to other systems according to standard protocols.
Reference books:
"Introduction to New Railway Signaling Technologies (Revised Edition)"/Lin Yujun/China Railway Press
"TJWX-2000 Signal Microcomputer Monitoring System"/Zhao Xiangrong/China Railway Press;