ELECTRIC, WITH AN EDGE
pad mounted transformer is a relatively common equipment in the power system, its application process is prone to failure, should be used in a regular maintenance way, the implementation of common failure analysis operation, in order to ensure that pad mounted transformer in the use of the process will not have problems. It is formed by the combination of coil and core, in which the core material is mainly silicon steel sheet, and the coil is mainly epoxy resin, which is non-flammable and insulating. Therefore, the pad-mounted transformer will not leak in the process of use, but even so, if the pad mounted transformer is not maintained for a long time, it will also break down because of the problems of the internal parts, so that the power system can not run smoothly, so it is necessary to carry out overhaul and maintenance of the pad mounted transformer. So there is a need to overhaul and maintain the pad mounted transformer, and reasonably apply the pad mounted transformer troubleshooting techniques.
If the pad-mounted transformer in the process of operation, the mechanical components of the uniform ringing is normal, but if the sound shows uneven changes, or there are abnormal ringing problems, you need to check it. The reason for this may be that the actual load of the pad mounted transformer increases, so that the load capacity of the pad mounted transformer presents an unstable change, triggering a fault.
The common fault of pad mounted transformer is tripping. The reason is the incorrect operation of the employees or the internal failure of the pad mounted transformer, which leads to the tripping problem of the pad mounted transformer.
If the pad mounted transformer has been in use for a long time, oil leakage may occur in the iron plate area and at the sealing points. If the staff does not find this problem in time, it will increase the impact on the pad mounted transformer, so that the location of the leakage will change, leading to leakage of electricity or other failure problems.
Under normal circumstances, the oil temperature inside the pad mounted transformer needs to be controlled at about 95℃, and the probability of oil temperature increase needs to be controlled at less than 55℃. However, if the padmounted transformer fails, its oil temperature will show a continuous increase, exacerbating the impact of temperature anomalies.
Usually, the discharge problem of the pad-mounted transformer is mainly caused by the following reasons: (1) Because of the error of the pull plate in the pad mounted transformer in the process of placing, so the distance between its position and the coil is too close, which will cause interference with the pad mounted transformer’s operation and the discharge problem. interference and discharge problems occur.
(2) Because the pad mounted transformer is easily affected by external disturbances during the transformer period, causing the pad mounted transformer inside the pad to have the problem of creepage, and if the low-voltage power needs to be transformed into high-voltage power, it will lead to the instantaneous voltage increase, even exceeding 35kV, which is also prone to cause the problem of discharging.
(3) due to the pad-mounted transformer in the application process needs to be set in the cable dense area, need to be placed in the high place, if there is a false connection problem nearby, will cause the distribution of components such as split tube, corner connection tube and other components of the distribution of uneven, resulting in the pad mounted transformer is too dense phenomenon occurs, which will also improve the probability of discharge. This will also increase the probability of discharge.
(4) Because of casing flashover, the temperature of the casing inside the pad mounted transformer is relatively high, and the casing will be aging in the process of continuous heating, so it will increase the probability of short circuit.
Intelligent fault identification methods are applied to realize the retrieval of pad mounted transformer.
First of all, experienced experts should be set up to analyze the faults of the pad mounted transformer with their own experience, gradually create a fault diagnostic system for the pad mounted transformer, create a database to understand the symbolic data content that exists in it, and measure the state of occurrence of the data in order to resolve the faults that exist in the current period of the pad mounted transformer.
Secondly, in the process of applying the expert system, it is possible to evaluate the fault identification model and clarify the interactive characteristics of the fault content, so that the staff can grasp the fault information and complete the corresponding identification work in a short time. However, this mode of operation, which relies too much on the expert system, is not applicable to the variable and complex pad mounted transformer detection work, and there may be inferred failure information, so that the expert system identification of faults still needs to be improved.
The neural network identification method is mainly applicable to the blocks with high diagnostic difficulty, to master the nonlinear problems existing in them, and to create the diagnostic model of the faults in order to increase the adaptability of the neural network identification.
First, the neuron network can be formed so that the fault can be self-organized and self-adaptive, and the generalization ability of the neural network can be strengthened to assist the pad mounted transformer in the identification work.
Secondly, artificial neurons are used to match the power pad mounted transformer with the network, and hybrid diagnosis is applied to recognize the faults in the pad mounted transformer, and then the neurons are trained to shorten the time of the diagnosis work, and to retrieve the fault problems of the pad mounted transformer.
According to the fault state of pad mounted transformer to analyze, grasp the uncertainty value, using conventional operation, apply fuzzy algorithms, and then facilitate the staff to retrieve the data information in a short period of time, the use of fuzzy reasoning, to complete the pad mounted transformer’s intelligent fault diagnosis work. Firstly, the fault prototype as well as the type of the pad mounted transformer can be analyzed based on the fuzzy reasoning, so that the fault identification work can be carried out smoothly. Secondly, the fuzzy processing of boundary value, fuzzy clustering and fuzzy relationship should be adopted so that the intelligent recognition algorithm can be reasonably applied to retrieve the fault information of pad mounted transformer, and the faults can be categorized by adopting the accurate recognition method.
In response to the sound abnormal ringing problem within the pad mounted transformer, the main source of the sound should be analyzed to confirm which area has a problem. For example, the pad mounted transformer's operation sound change is suddenly high and low, in the pad mounted transformer's change stage does not have obvious regularity, the probability is caused by the increase of transformer charge. This means that there is a problem in the large components within the pad mounted transformer, and maintenance workers can analyze it in relation to the state of the charge to accurately grasp the cause of the fault in order to rationally apply a solution. If, after testing, the charge is within a reasonable range, there is no need to treat the pad mounted transformer.
At the same time, it is also possible to observe the state of the pad mounted transformer and confirm whether there is a problem with the pad mounted transformer by means of sensing the temperature change of the housing of the pad mounted transformer and monitoring the amount of oil in the pad mounted transformer. However, during the implementation of the above work, insulation must be properly handled to prevent the maintenance personnel's own safety from being affected.
For example, in the padmounted transformer operation link there is a bursting sound, at this time, the internal pad mounted transformer can be closely examined, the use of targeted detection methods, to confirm the source of the sound, to confirm whether there is a pad mounted transformer overloading problem, and timely and Communicate with the higher management in a timely manner, so that the power supply circuit can operate normally and reduce the probability of overloading.
In addition, if the load stops during the maintenance of the pad mounted transformer, a no-load problem occurs, causing abnormal noises to occur inside the pad mounted transformer. If the sound is persistent, it indicates that the cause of the problem is not internal, but external. In this case, the maintenance personnel can search for the location of the sound so that the equipment can be stopped and the problem can be determined and dealt with appropriately using the dismantling method.
In order to avoid the problem of tripping of the pad-mounted transformer, the staff can carry out the work in accordance with the standards to prevent the human factor and external interference factors from affecting the operation of the pad mounted transformer. First of all, the inspection work can be carried out in a timely manner, so that the staff can monitor the status of the electric switch to confirm whether it can supply power normally. If it is not caused by human beings, then we can check its internal state and further check the causes of the problems. For example, the condition of the radiator can be checked to see if it is faulty, and if it is faulty, it can also cause the temperature of the pad mounted transformer to change, causing it to continue to rise, which can easily lead to problems such as fires.
In this regard, firstly, the maintenance personnel can be asked to take insulation measures and disconnect the circuit breaker inside the pad mounted transformer to prevent the tripping problem from occurring. Secondly, the troubleshooting method can be used to restart the pad mounted transformer to ensure that the maintenance personnel can successfully complete the overhaul work, and do not force the power supply to prevent the pad mounted transformer from causing a greater impact.
Finally, regardless of which aspect of the cause of the problem, maintenance personnel need to report the problem to the relevant departments to prevent the pad mounted transformer tripping problem on it. And the staff must check the status of the equipment in real time and carry out inspection operations to avoid exacerbating the impact of the tripping problem. In this way, if the pad mounted transformer tripping problem occurs, it is necessary to give a response in the first time, and restore power supply in a short period of time to avoid the disturbance of people's electricity consumption.
If the oil level inside the pad mounted transformer is deviated, problems such as oil leakage and oil spraying may occur, so that the pad mounted transformer no longer operates normally. In this case, after the oil condensation, the top oil temperature should be checked, and its status should be detected in real time, so as to understand the loads in the pad mounted transformer and confirm the position of the cooler, so as to ensure that the pad mounted transformer can be restored to normal.
Firstly, check the condition of the pad mounted transformer seals to eliminate the problem of oil leakage due to aging, confirm whether the sealant is qualified and replace it regularly.
Secondly, strengthen the attention to the sealing point, to ensure that in the sealing work before the implementation of the staff can do a good job of cleaning the site operation, the use of reinforcement treatment, so that the oil can be uniformly radiated, so that the application of sealant can be extended, to assist in the operation of the pad mounted transformer. Finally, if the valve is not closed tightly, it will also cause the problem of oil leakage occurs, so, according to the state of the valve, to determine whether it needs to be replaced. In addition, if the welding work inside the pad mounted transformer is not up to standard, welding with oil can be used so that the welding effect can be improved to avoid the risk of oil leakage.
In the pad mounted transformer if the metal components of the temperature rise problem, will lead to the pad mount transformer temperature of the overall increase in the problem, once the heat dissipation device is not opened in time, will increase the temperature of the oil.
Then, the maintenance personnel need to grasp the status of the flow meter in time, retrieve the measurement data and make a reasonable judgment. If the valve inside the pad mounted transformer is not open, open it in time. If the internal design of the pad mounted transformer is not reasonable, it will also cause the internal oil temperature to rise.
If the oil temperature rises due to magnetic leakage, in serious conditions, it will cause the pad mounted transformer to explode. At this time, the maintenance personnel can reasonably use the magnetic insulation material to assist the operation of the pad mounted transformer, so that the pad mounted transformer in the operation process will not occur in the heat dissipation problem. The replacement of the cooling device can also be used to prevent the problem of abnormal oil temperature.
For the maintenance of pad mounted transformer, regular monitoring should be adopted to deal with the problem of pad mounted transformer discharge. First of all, let the staff analyze the status of the temperature control and temperature display instrument, record the display value, ensure that the staff can carry out regular site surveys, confirm the value in the instrument and increase the frequency of meter reading, in order to analyze the rated current in the electric power pad mounted transformer in real time.
Alternatively, remote monitoring can be used to check the current, voltage and winding temperature on a regular basis to confirm the maximum winding temperature of the pad mounted transformer during operation and prevent the pad mounted transformer from discharging. Secondly, if the surface of the pad mounted transformer exists in the case of debris piled up, it will have a direct impact on its electrical conductivity, so that its humidity presents a higher state, which can not ensure its smooth operation and increases the probability of the occurrence of discharge problems. At this time, managers can let the pad mounted transformer stop working, the surrounding debris to deal with, to prevent external interference factors on the operation of the pad mounted transformer.
At the same time, the inside of the casing can be painted with relatively high performance paint, so that the leads and the casing can be tightly connected, so that the contact surface inside the pad mounted transformer will not occur oxidation problems, so that its surface looks shiny. At the same time, employees can regularly check the condition of the casing to prevent the casing and leads from deteriorating or malfunctioning. In the event of such problems, sleeves and related components can be replaced in a timely manner.
Finally, if the pad mounted transformer has the problem of excessive internal voltage, it will also lead to the emergence of the discharge problem, so the maintenance personnel can use tools to assist them in picking up the debris in the field, so as to reasonably deal with the discharge problem of the pad mounted transformer.
As in the pad mount transformer, the winding is its circuit component. Therefore, in the process of operation, in order to prevent the generation of winding faults, the state between phases as well as turns should be understood to prevent the occurrence of short-circuit problems therein. If there is a short-circuit phenomenon, the winding current can be more than 10 times of the rated current, so that the winding continues to heat up, which not only accelerates the probability of aging of the pad mounted transformer, but also increases the impact on people's safety.
Therefore, in order to realize the treatment of winding failure, we can grasp the deformation condition and the loosening of the winding, confirm the existence of defects and carry out reinforcement treatment. In this way, the maintenance personnel can replace the windings and spacers to prevent the pad mounted transformer in the application process of winding failure. Solve the short circuit of the winding, short circuit between the turns, to promote the successful completion of the winding repair work, do a good job of the winding replacement operation.
As the iron core as the magnetic circuit part within the pad-mount transformer, its failure occurs mostly in poor grounding, core multi-point grounding, short circuit between iron chips. On this basis, once a kind of closed circuit is formed between the contacts in the multi-point grounding link of the iron core, loop current will be generated, resulting in the local occurrence of overheating problems. Core failure, on the other hand, is triggered by damage to components such as the threading screw.
Therefore, when dealing with this part of the problem, the inspection method of lifting the core can be used to understand the winding status of each phase, check the DC resistance and check the appearance of the core, so that the current will not be shocked in a short period of time, preventing the core from appearing to burn out information, which will enable the remaining core to be grounded smoothly, preventing the generation of core failure.
In order to ensure the smooth operation of the pad mounted transformer, attention should be paid to its insulation performance to prevent the occurrence of insulation damage, dielectric loss exceeding the standard and other problems. Firstly, the running time of the insulating components in the pad-mount transformer can be detected so that the oil channel will not be blocked, and regular inspection methods should be adopted to clean up the surrounding debris to reduce the impact on the pad mounted transformer. Secondly, the state of oil level and oil quality should be checked, and if it has a big change after a long period of operation, it can be replaced in time to prevent oil seepage and oil leakage, and do a good job of checking for moisture to realize the handling of pad mounted transformer insulation faults.
In summary, as the pad-mounted transformer as a key equipment in the power system, so, in order to ensure that it can run stably, it is necessary to adopt a regular patrol, so that maintenance and installation personnel to monitor its oil level, sound, oil temperature and other status, adhere to the principle of early discovery, early treatment, so that the pad mounted transformer can run smoothly!
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