China Powerbookmark0 found SF% electrical equipment failure through the detection of SO Zhang Zhongqi, Lian Hongsong Fujian Electric Power Research Institute, Fuzhou, Fujian, higher content. There are many methods for detecting SO%, and the detection tube is simple and convenient, and has sufficient sensitivity. Early detection of SF electrical equipment failures, improving the reliability of power supply and judging whether SF electrical equipment needs to be repaired are important issues of concern to the power sector. At present, the traditional electrical test methods sometimes seem to be inadequate for how to diagnose SF electrical equipment faults early. Through the fault measurement analysis and test comparison, it is indicated that the electrical equipment can be judged to be faulty by detecting the SO% content in the SF electrical equipment. In order to diagnose electrical equipment failure, it is a future development direction with huge market potential and application value. 1 Method proposed SF gas has excellent insulation properties and arc extinguishing characteristics, and has been widely used in electrical equipment such as fully enclosed combined electrical appliances (GIS) and high voltage circuit breakers. The quality of SF new gas and operating gas will directly affect the safe operation of SF electrical equipment, so it is important to strengthen the quality supervision and management of SF gas. The industry standard DL/T596-1996 "Procedure Test Procedures for Power Equipment" puts forward specific requirements for the test items and cycles of SF gas in operation. When a device fails, SF gas decomposes and reacts extremely intensively with insulating media or metals near the point of failure, producing different types of reaction products. At present, some departments at home and abroad have paid attention to the research on the decomposition mechanism of SF gas and the detection of decomposition products. It is hoped that through the daily monitoring of the operating gas or the gas analysis when the equipment fails, it can also be used to judge whether the SF electrical equipment is faulty or faulty, just like the diagnosis and diagnosis of the transformer operating state by using the dissolved gas component and content in the transformer oil. Type and degree of failure. In 1998 and 1999, Fujian Electric Power Test Institute conducted some tests on the decomposition products of SF gas in operation. In March 1999, it was found that a 500kV current transformer had a discharge fault inside by detecting SO%. In October, it was found that %% was found. In 034 GIS, the isolation of the knife gate caused overheating and discharge failure, thus realizing the importance of analyzing the decomposition products of SF gas in the operation, and also confirming that the detection of SO% content can detect whether the SF electrical equipment is faulty. 2 Specific examples Quanzhou 500kVSF*TA discharge failure Quanzhou 500kV substation was put into operation in March 1998. When I visited the scene on the night of 1st of October, 1998, I found that the 5023B phase TA of Quanzhou Substation China Powerbook6 had a puff like boiling water. At that time, the load was 390,000 kVA. After the load was reduced, there was no sound for a while. Then there is a sound. When the operator turns the 5023TA into a hot spare, the sound has not been eliminated, and there is no sound until it is turned into a cold standby. At the same time, it is found that there is induction electricity generated on the support column ground line. When the device was removed, it also smelled a strong pungent smell. After analysis, it is considered that there is a discharge fault inside the equipment, and the equipment is sent to the manufacturer for dismantling. It is found that the internal fault of the 5023TA is that the screw on the support of the fixed secondary coil is not tightened during installation, and loosening occurs to form a discharge phenomenon. 2.2 Shunyu Power Plant 220kVGIS Short-Circuit Fault The Shuyu Power Plant booster station GIS has 8 intervals, and the equipment model is B95/4, which is the product of Alstom Company of France. On December 6, 1998, the electrical test found that the B phase of the 2213 circuit breaker at the B09 interval was short-circuited to ground, and the casing between the circuit breaker air chamber B09G0-B and the TA air chamber B09G3-B had a burnt mark during the air pressure check. I also smelled a strong pungent smell, and after disintegration inspection, it was found that the insulation cone between the G0-B and G3-B chambers at B09 interval had been burnt, and the phase B casing was static to the G0-B chamber. The contacts and the conductive rods are severely overheated, and many white powders are deposited in the gas chamber. Through the above two faults, it is believed that the strong pungent smell is likely to be the sulfide produced by the decomposition of SF6. Therefore, it is turned to detect the S2 content of the SF6 electrical equipment to see if the SF6 electrical equipment malfunction can be found. 2.3 Xiamen 500kVSF6TA discharge fault mother-over-current over-current protection action, 5021 switch trip, the main transformer is out of service. Through the comprehensive analysis of the data of the main transformer oil sample chromatographic analysis, the main transformer oil temperature is normal, the main transformer busbar protection is not active, etc., it can basically indicate that there is no problem with the main transformer body. From the analysis of fault recording data, it can be preliminarily judged that C is relatively short-circuit fault, the short-circuit current peak is 6 000A, and the fault point can be delimited between the main transformer 500kV bushing and the circuit breaker. But this includes a large piece of equipment for two incoming loops, including casing, lightning arrester, capacitive TV, SF6 filled TA, SF6 circuit breaker, porcelain bottle, etc. After a series of electrical tests such as comprehensive external flashover trace inspection and insulation resistance, DC resistance, dielectric loss, and AC withstand voltage on these devices, no problems were found. After testing the SF6 gas decomposition products on the SF6-filled equipment, it was found that the S2 content of the 5021 current transformer C phase reached 200! L/L, SF6 gas purity is 99.29V/Y), and adjacent SF6 current transformers such as phase A of 5021, phase C of 5023 can not detect S2 component, and the purity of SF6 gas component is above 99.79. Therefore, it is found that there is a serious discharge fault inside the 5021 TAC phase. 5021 current transformer C phase disintegration inspection, found that one of the four solid insulators supporting the secondary coil due to quality problems, poor insulation performance, severe burnt by current, resulting in 500kVTA high voltage to ground short circuit. 2.4 Fuzhou Hongshan Substation 220kVGIS Overheating Discharge Fault 220kVGIS of Fuzhou Hongshan Substation is a product of Pingdingshan Switch Factory, which was put into operation in 1995. At noon on October 26, 1999, the main transformer of the No. 2 main transformer moved, causing the GIS22B circuit breaker to trip. On the morning of the 27th, the SF6 gas decomposition product was detected, and the gas in more than 10 gas chambers was measured. As a result, an abnormality was detected in the 22B1 air chamber: the S2 content inside the gas chamber reached 700! L/L, SF6 purity is 98.99V/V), SF6 gas humidity is 330! L/L, while the results detected by other air chambers are normal. Therefore, it is considered that the air chamber is malfunctioning, causing the circuit breaker to trip. After disintegration inspection, it was found that about 1/4 of the static contacts of the isolating knife gate were burned and melted, and some of the moving contacts were also melted, and the melted slurry splashed upward along the direction of the conductive rod, and the basin on the moving contact side was sprayed. The insulator is blackened upwards. The burning and testing conditions are as shown in 4; Volume 34: Detecting S02 by S02, electrical equipment failure 2001, the first phase of 2.5, 1998 and 1999, S2 gas detection, other equipment kV current transformer 18 phase; Xiamen Tongan substation 500kV current transformer 24 phase, switch 24 phase; Xiamen Tongan Substation 220kV circuit breaker 2 sets; Fuzhou Nanjiao Substation 220kV circuit breaker 10 phase, 110kV circuit breaker 8 sets; Fuzhou Nanmen Substation 220kVGIS; Fuzhou Hongshan Substation 220kV GIS224 interval, 222 compartment air chamber and circuit breaker; Dehua Power Company 3 sets of 110 kV SF-breakers; 3 sets of 110kV SF-breakers of Nan'an Power Company; 4 sets of circuit breakers manufactured by ABB of Shaxikou Hydropower Plant; 16 phases of 0110kV circuit breakers of Zhangping Power Plant; 220kVGIS of Huaneng Fuzhou Power Plant Air chamber, etc. These devices were operating normally and none of the S2 components were detected. Two examples in Sections 2.3 and 2.4 demonstrate that SF-electrical equipment failure can be detected by detecting the SF-electrical equipment S2 content. The data in Section 2.5 indicates that a properly functioning device cannot detect SO:. 3 Mechanism Under normal conditions, the arc generated by the operation of the circuit breaker, due to the special structure of the arc extinguishing chamber, the SF-gas is decomposed by the arc to form an ionic group and a radical group), and then rapidly recombined into a very short time. SF-, the recombination rate is above 99.9%, and only produces very few low fluorine cracking products. When the equipment fails, the fault current causes the SF-gas to undergo a cracking reaction, and the cracked product is further chemically reacted with the insulator, the metal, etc., and the final decomposition product is quite different from the normal time. A lot of research shows that SOF2 is the main decomposition product in arc discharge; in spark discharge, SOF2 is also the main decomposition product, but the ratio of SO2F2/SOF2 is increased, S2F10 and S2F10O can also be measured; in corona discharge, SOF2 It is still the main decomposition product, but the SO2F2/SOF2 ratio is higher than the spark discharge. Thermal decomposition of SF-gas may also occur, and the thermal decomposition products may detect the presence of SOF2, SO2F2, and SO2. In the arc and thermal decomposition process, SOF2 is the main decomposition product, if the SOF2 content is detected as 1! L/L indicates that there is an arc discharge in the gas chamber. SF- is decomposed into SF4 and F2 under the action of electric arc. SOF2 is formed by the action of SF4 and water molecules in the gas chamber. The reaction formula is: SF-=SF4+F2SF4+H2O-! SOF2+2HF SF-The composition and content of the product under the action of the arc is related to the arc energy, and also related to whether there is solid insulation material. For example, the experience of the French power company shows that the insulator in the GIS flashes. SO2 is more than gas breakdown. The SO2 gas can be produced by the reaction of SF-decomposition with the decomposition of the insulating material, mainly by the hydrolysis of SOF2: SOF2+H2O SO2+2HF thermal decomposition test can simultaneously detect SO2 and SOF2. SOF2 is SF-main decomposition And SO: is the final product of hydrolysis. 4S2 detection method SF-decomposes under the action of high energy factors such as arc, and the generated decomposition products are stable in SOF2, SO2F2, S2, 10O, SO2, HF, etc., and are prone to exist in SF-gas for a long time. The analytical results show that the SO2, HF, SOF2, and SO2F2 components in the sample are generally high in content. In order to detect the cleavage products of SF-gas, gas chromatography, chromatography/mass spectrometry, visible spectrophotometry, ultraviolet spectrophotometry, infrared spectrophotometry and nuclear magnetic resonance can be used. Gas chromatography with thermal conductivity and flame photometric 2 detector can detect more than 10 kinds of SF-decomposition products such as SOF2, SF4, SO2, etc.; all the decomposition products can be detected by chromatography/mass spectrometry, and the sensitivity is high and detectable. Out of 1! L/L SOF2; infrared spectrophotometry can measure SOF2, CF4, SO2 and moisture. This time, SO was measured: a gas detection tube was used. In the early 1980s, Mitsubishi Corporation of Japan proposed the use of gas detection tubes to determine the change in the operating state of SF-electrical equipment by measuring the HF content, which serves the purpose of early diagnosis. The detection tube can be used to determine various impurity components in SF-gas, such as O2, CF4, SO2, CO, COS, HF, SOF2, SO2F2, etc. Currently, there are practical values ​​of HF detection tube and SO2 detection tube. The detection limit of the HF detector tube is 1.5! L/L, SO2 detection tube detection lower limit SO2 detection tube is made according to the principle of redox reaction. It is coated with iodine-containing starch on a carrier, then filled into a glass tube, and engraved with a scale on the tube wall. When the sf6 gas passes through the glass tube, the so2 in the gas reacts with 12: the starch reaction turns the original blue color into white, and according to the length change of the glass tube, the volume mass of S2 in the SF gas can be measured. Still another S2 test tube is filled with an alumina carrier in a glass tube coated with cesium chloride and a +H indicator. At the time of measurement, S2 reacts with B-C12, and the generated HC1 reacts with the +H indicator to become yellow. 5 points of view by detecting SF decomposition products, diagnosis of electrical equipment failure, is a very meaningful work, the domestic pace should be accelerated. The fault characteristic components are S0F2, S2F2, CF*, S2, HF and hydrolyzable fluoride. An example of determining the failure of a solid insulating material by measuring CF* has been reported in the country. At present, the measurement method requires more precision instruments, and the samples are often brought back to the laboratory. Our hospital is transforming instruments such as portable chromatographs to facilitate on-site testing. The use of gas detection tube, the instrument is small in size, easy to operate, especially suitable for field use. For example, if there is only qualitative or non-SO: gas, it can be combined with trace moisture test, and the exhaust gas can be used to pass the gas through the detection tube, which is quite convenient and sensitive enough. At present, only two types of detection tubes, S2 and HF, are available in China. It is recommended to develop other component detection tubes as soon as possible. The examples given in this paper confirm that SF electrical equipment failure can be found by measuring SO:. This method is particularly suitable for failure types involving solid insulating materials. Since there are very few reports of such detections that can be seen at present, the work done by our hospital is quite limited, so the sensitivity cannot be evaluated. I hope to summarize the experience through extensive adoption. One thing is certain. Any one of the determinations of SF decomposition ▲ Xi'an Xijiao Thermal Power Plant ion exchange resin pollution recovery project has been a complete success. The Xi'an Xijiao Thermal Power Plant ion exchange resin pollution recovery project undertaken by the Northwest Electric Power Research Institute Environmental Protection Office has passed the acceptance test. . Xijiao Thermal Power Plant was put into operation in 1993. Since 1999, due to various reasons, the chemical demineralization system ion exchange resin has been seriously polluted. The double-bed cycle water production is only about 10h, which is less than half of the normal value; the mixed bed operation cycle is reduced from one month to one week. The effluent conductivity is as high as 0.5 or more (standard specification <0.2 cm), which has a great impact on production. The plant commissioned the Northwest Electric Power Test Institute to conduct an analytical test to confirm that the pollutants were mainly iron and suspended matter impurities. The recovery method was to scrub the suspended solids with compressed air, separate the broken tree, and use the self-developed resin to recover. Remove iron. In addition, replace the 001x7 strong acid cation resin that has reached the scrapping standard and adjust the ratio of the mixed bed resin. The recovery and debugging work lasted for 451. After the resuscitation of the resin, the acid was faster than the method of diagnosing the failure of the 2.87 object, and the data must be observed sharply. The method of determining S2 is no exception. A considerable amount of adsorbent is placed inside the SF electrical equipment, mainly including molecular sieves, activated alumina, activated carbon and the like. These adsorbents are effective in adsorbing moisture and SF gas decomposing substances, which is absolutely necessary to ensure the safe operation of the equipment, but it also brings great difficulties in trying to diagnose the operating conditions of the equipment by detecting the decomposed substances. Therefore, when an abnormal signal appears in the device, the action must be fast to reduce the influence of the decomposition product being adsorbed. Routine analysis and testing, the test should be accurate, and the changes in the concentration of the decomposition products should be observed sharply. Do not let go of the suspicious "where, compare with the data of the surrounding equipment, find special", should pay attention, follow Do not let go. 6 Conclusions The S2 content analysis method was applied in the SF electrical equipment fault finding, and the results proved to be effective. Compared with other methods, the S2 content analysis method is simple, low in test cost, and can be monitored on site or online, and the requirements for personnel are not high, which are beneficial to the actual needs of the project. The method for detecting the content of SF decomposition products has the same development prospects as the method for analyzing the faults of electrical equipment in the analysis of dissolved gases in oil. More trials and improvements will be made in the future to make this approach more mature. Polar Fleece Fabric,Custom Dyed Fleece Fabric,Polyester Printed Fleece Fabric,Anti-Pilling Printed Fleece SHAOXING XIANCHENG TRADING CO.,LTD , https://www.xcxssfabric.com