Fault finding of the hottest dispatching automatio

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Fault finding of dispatching automation

Abstract: dispatching automation is a complex system engineering involving multiple professional technologies, and it is a combination of high-tech equipment. In addition to the continuity and safety requirements of the power system, once the automation system fails, it must be eliminated in time and quickly, so that it can resume the normal operation of constant deformation control as soon as possible

key words: dispatching automation power system fault finding 1 foreword dispatching automation is a complex system engineering involving many professional technologies, and it is a combination of high-tech equipment. In addition to the continuity and security requirements of the power system, once the failure of the automation system occurs, it must be eliminated in time and quickly to make it resume normal operation as soon as possible. 2. Fault analysis and inspection methods (1) system analysis method: first of all, you should have a clear understanding of the automation system: what subsystems are composed of, what is the working principle of each subsystem, what is the main equipment of each subsystem, and what is the function of each equipment, etc. The system analysis method is to analyze and judge the fault of automation system by using the correlation and comprehensive principle of system engineering. System analysis is actually a logical inference method. If you know the function of the equipment, you will know the consequences after the equipment loses its function. From this, you can know what kind of faults occur in the system and what equipment causes them. For example, the information of a substation in the main station of an automation system is sluggish, and the telemetry data that should have been changed once in a few seconds according to Mitsubishi material is no longer changed (or all are zero). At this time, the experimental force of other substations is large tension FM, and the information of the substation is normal. After checking that the RTU of the substation is normal, it can be judged that the fault is in the channel. Next, we need to analyze that in addition to the communication equipment, the signal channel also includes the modem at both ends of the dispatching station and the substation, and the terminal of the distribution line frame of the communication equipment. (2) Exclusion method: simply speaking, it is the judgment method of "either this or that". Because the automation system is more complex, and it is also related to the primary and secondary equipment of the substation, the elimination method should be used to determine whether it is the automation equipment or related other equipment faults. For example: ① the position signal does not change when the circuit breaker is operated remotely. If the operator of the master station remotely operates a circuit breaker in the substation, the display at the dispatching end is correct, but it does not reflect the displacement of the circuit breaker. In this case, the system analysis method can be used, such as judging that the main station and channel are normal, then the problem lies in the substation. First, check whether the position contact of the circuit breaker of the substation is correct when it is opened and closed locally. If the position contact state of the circuit breaker remains unchanged no matter whether it is closed or opened, it proves that the problem lies in the position contact. If the status of the position contact is correct and the relevant cables are in good condition, it can be considered that the problem lies in remote signaling, and other problems can be eliminated. ② Bus grounding signal. When the dispatcher reflects that there is a single-phase grounding signal in a substation, first of all, the system analysis method should be used to judge whether the breaking of the high-voltage warning line that challenges the national policy is a correct signal or a wrong signal. If it belongs to the correct signal, it must be that the bus or feeder of a substation really has single-phase grounding. If it belongs to the wrong signal, it is necessary to distinguish whether it is the problem of the automation system or the related primary and secondary equipment. In this case, if the dispatching terminal can timely reflect the "yes" and "no" signals of single-phase grounding when the xjj contact is short circuited or disconnected, the automation system is in good condition. The fault is not here and can be eliminated. Only the part above the xjj contact (i.e. do not doubt the bus grounding), and the fuse on the primary and secondary sides of TV is fused), the fault must be in the remote signaling part. The exclusion method is not absolute, which requires telecontrol personnel to accumulate more work experience. (3) Power supply inspection method: Generally speaking, after a period of operation, the automation system enters the stable period, and the equipment itself has relatively few failures, but it often has equipment failures. In this case, check whether the power supply voltage is normal. Poor contact of fuse circuit board will lead to abnormal working power supply and equipment failure. Moreover, whether it is microcomputer, RTU, carrier machine and other equipment, there are several DC working voltages. If one of them is abnormal, it may lead to equipment failure. It should be carefully checked. This method is applicable to the equipment that has determined the fault through system analysis and troubleshooting. (4) Signal tracking method: the automatic system completes its function with the help of data communication, and the signal is invisible and untouchable, but it can be detected with the help of oscilloscope and millivoltmeter. Tracking whether the signal is normal through oscilloscope and millivoltmeter is also an effective method to judge the fault point. If the master station system works normally and the signal amplitude measured by oscilloscope or millivoltmeter at the transceiver end of the modem of the RTU is very small or the signal can not be received at all, it can be inferred that the signal sent by the master station to the RTU is abnormal. The communication cable and communication equipment of the wiring rack terminal of the cable communication equipment can be checked from the transmitter end of the modem of the master station. In this way, the fault can be found. (5) Replacement method: if the faulty equipment has been found through the above methods, and these equipment are very complex and difficult to repair at the moment, spare parts can be used for replacement. First restore the normal operation of the system, and then repair the faulty equipment. The RTU using STD bus technology is generally equipped with a spare template. If a function fails and it is determined that a function module fails, the RTU can be restored to normal by replacing the template. 3 conclusion the above is only a general method to find the fault of the automation system. From the perspective of some county dispatching, the reason that hinders telecontrol personnel and on duty operators from quickly troubleshooting is that they are not familiar with the working principle of each component of the automation system and are not rich in experience. Only by strengthening the continuous improvement of the knowledge and practice quality of the above personnel, sending them out for study or on-the-job training, and improving their business knowledge, can we achieve the goal of "knowing the disease" and "eliminating the disease" in the maintenance and overhaul of the equipment

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