Lutsenko Roman;

Figure 3 — Schematic diagram of the oil cooler in the cooling system of DC.

The cooling system is a broker at present me main cooling system, increasing the trans shaper and powerful electro autotransformer stations. The system provides a forced circulation of oil through the cooler by means of special pumps and differential intensive air cooling air cooling using fans (Figure 3).

The cooling system is designed for DC transformer with a rated load at room temperature calculationambient +40 ° C (average daily temperature no more than +30 ° C) and consists of several structurally complete cooling 2W. ~ Devices. Each cooling unit includes a chiller, an adsorption filter, blower, electric pump to circulate the oil.

Continuous treatment and recovery of oil occursried out at the adsorption filter connected to the count ¬ lecturers each cooler. Oil circulation pro ¬ exhaust oneself be wasps and l b s Cove or E-type pumps ETST-100/15, ETSTE-160/100, ETSTE-100 / 15, or ETST-63/10 ETST-100 / 8 (first time used Cantilever pumps 6K-12a).

To block or main control displays alarm of fault in the cooling system (engine shutdown cooling system, the disappearance venii stress on the engines, achieving the effective temperature limit upper layers of oil, stopping the circulation of oil, power system operation ABP cooling, etc.) If a faulty alarm, expluatirovat transformers with DC system is not just solved.

Before the commissioning of each cooling device schee have filled transformer oil of vector with a temperature of +50- s-| -60 ° C under pressure leniem 2 kg/cm2 for 1 h, after which the industr vayut dry oil.

Fill coolers oil produced iodine vakuumom from the transformer tank in accordance with the Institute of struction for installation. After filling the oil must tstoyatsya for 5 hours then examines the lack ozduha lriotkrytiem vozduhovgpusknyh plugs and switched to white oil circulation. After 12 h of sludge Aslan transformer can be put into operation. It should be noted that all operations for the inclusion of powerful transformers are all macharge and must be conducted in respective dance with the factory instructions and trebovaniyam I PTE. I transformers with cooling DC distribution itany for continuous operation, only three included Eastholme cooling since heat transfer by convection 'radiation from the surface of the tank in the absence of cir-modulation does not exceed 10% of total losses transformation of the torus. Therefore, before turning on the transformer turns under Egruzku at least 2 / 3 working coolers, oil pumps redusmotreno switch. fan cooling circuit breakers at turn chairman of the HV transformer, and if the transformer mer in block with the turbogenerator, also when you turn on the generator AGW. When you manually turn first engines include oil pumps and then the fans blowing.

After a set of rated load on transformers mer or raise the temperature of the upper layers wla above +55 ° C must be the work of all workers coolers. When the automation as the temperature decreases to +45 ° C or lower the load of the working coolant is automatically disabled. It is saved in cooler re ¬ injected © work automatically when you turn off any worker in the cooler when the summer time, even during all the working coolant temperature of the upper-sloel oil exceeds the maximum allowed: 75, or n-80 ° C, depending on the slime of the transformer. With decreasing oil temperature to +65 ° C cooler reserve should be disabled.

With the disappearance or decrease in voltage which work power supply cooling devices, up to 85% provided a second source of ABP.

Transformers and auto-cooling system with DC and C in case of emergency termination of pabots or fans circulating the oil can work thief with a rated load do'teh long as the tempeture of the upper layers of oil does not reach the maximum permissible values for transformers up to 250 MB- A + 80 ° C, more than 250 MV-A + 75 ° C, but not more than 1 h, as in this mode greatly increases the temperature difference in height of the transformer tank and can be dangerous mechanical stresses in the active part. During this time must be taken to restore the cooling and unloading the transformer in accordance with local instruction. If the transformer is already working with the marginal rate of perature at the time of exit from the cooling device, the duration of his work with disabled circulating oil or blowing should not be more than 10 minutes.

The work of the transformer in the modes. bounded off in the cooling system and temperature of the upper layers of oil, equal to 75 or +80 ° C, no more than 30 minutes without exceeding these temperatures.

In order to avoid overheating in all transformers with cooling DC and C, plants re ¬ recommends to plant protection, triggered by high oil temperature or 4-75 GHS 8, and 10 minutes to shut down the existing block or the transformer.

If the load is lower than the nominal transformer, full or partial shutdown of fans in the presence of oil circulation in the winter or partial noah off. Chillers in the summer, is permitted only when the temperature of the upper layers of oil is less than-f-45 ° C.

Experience in operating transformers with external cooling systems at low temperatures (showed that the oil circulation pumps must include chat at the oil does not lower than -10 ° C. This is due to the fact that at a lower temperature increase creases viscosity and considerably worsen the condition of the pumps Vija of overload. BoE elektronaso raw in such cases to improve circulation to • include at the same time. "fans blowing in the warm up transformer after the in minus helium temperatures should be included only when the temperature is lowered achievement the upper layers of oil +45 ° C.

To avoid failure of the apparatus of control cooling system with decreasing temperature 'ambient to -20 ° C should be included in grevatelnye elements of the control cabinet. Operation of transformer cooling system of DC free signal to stop the circulation of oil, cooling water or the fans to stop permitted. Due to the fact that when you install there are significant vibrations tank often rimenyayut removal coolers on individual foundations poison to the transformer. This leads to what extent bschaya pipe connecting the coolers v tank reaches 200 m. The use of real carbon steel tubes and pipes cooling creates a great danger of contamination of the transformer mass W cuttings. Except where dirt can accumulate small metal, rust, paint, handed down from the in the tank with oil. To avoid contamination of oil lately connecting pipes is to use stainless steel. 241 .516-871

When operating the cooling system DC need to pay attention to dimo ensure safe operations of oil pumps and fans blowing.

3 Cooling System maslovodyanogo (C)

ensures a high performance cooling vaeth transformers. Plants are very compact maslovodyanogo cooling, take up little space and 'Economical,> but it takes place them in warm rooms and increased friction ments to the level of exploitation.

Figure 4 — Scheme maslovodyanogo cooling of the transformer-type C

1 - transformer tank, 2 - with an engine oil pump, 3 - oil coolers, 4 - air tanks, 5 - manometer, 6 - differential pressure gauge, 7 - adsorber, 8 - filter.

In the scheme maslovodyanogo cooling (Figure 4) on a heated oil taken from the transformer tank mass lonasooom and, after coolers, which circulates cooling water is returned back to the bottom of the transformer tank. Oil pumps are installed in front of oil cooler necessarily, since if they are installed after masloohladi teley latter will operate in vacuum, which creates the possibility of leaks of water in oil in the presence of the smallest leaks, (Oil coolers pre furnisha, heat exchangers, tube type, work melting by counter Oil coolers races read so that they lowered the tempera round of oil on the 10-15RS.

Air collectors prevents the weight from the scrap transformer tank in the air, which appeared as a result of suction in all elements of Euclidean May qn but of cooling. The system provides for typically two or three oil pump and oil cooler two. Well established in the operation of electric pumps ETST-63/10 ETST-100/15 and used in the system cooling IU DC. When installing them almost completely. "Excluded suction air and increases the reliability of the entire cooling system.

On the power transformers installed three oil pump, two of which are constantly in the work of, and the third the automatic standby. Reserve maslonaoos automatically or at off chenii operating electric or inadmissibility under IOM increasing oil temperature.

The inclusion of equipment maslovodyanogo. Cooling must be done in a strictly defined spectral sequence, taking into account the temperature of the upper layers of the transformer oil. In any case, you include oil pumps and circulates through the oil coolers, Aslan, and then turns leading Howl-pump or opening of the electrified engine cooling water.

If the oil temperature is positive, the powerful ansformatorah working in alliance with the generators, aslonaeosy-engaged automatically when the excitation of the generator to I'I 0,85 f / HOM before turning on the network, and other transformers inclusion maslonaso os performed after inclusion to work. gtritsatelnyh When oil pumps including oil temperatures chayutsya to work after the oil temperature 5 ° C included in the transformer, and the water temperature reaches Doda oil +15 ° C. The operation should be maintained (regular oil pressure over evyshenie water pressure not less 0.2 kg / cm *. After turning the system maslovodyanom, cooling must be adjusted to set tnosheniya pressure water and oil, and 2-3 hours to achieve steady-le temperature reregime executed more control sistems .

Commissioning of the oil cooler after running repairs to the transformer to produce a preliminary translation of the trip element for the gasshields the signal. Be sure to let the air out of oil cooler after filling it with oil.

Turn off the cooling system maslovodyanoy proexhaust oneself in normal conditions after some time off after me transformer from the network. In this first closed cooling water access, but for those after some oil cooling oil pumps are disabled. .

Particular attention should be paid for exploitation tion system maslovodyanogo cooling in areas with low temperatures in winter. BoE equipment tion masloohladitelnyh plants should be time mescheno in warm rooms. After disconnecting the trans ¬ formators should be lowered from the water-masloohladi teley and avoid peremerzaniya petcock "past should be left open.

Due to a small area of smooth cooling tanks, all the devices of the cooling system must always be in regardless of the load transformer ¬ monochromator.

Cooling System maslovodyanogo C compared to the system mist cooling DC is more efficient, has a smaller size and weight, lower cost and operating costs of the unit power. Temperature of the upper layers of oil power transformers during the summer at the maximum for gruzkah not exceed 50-55 C, so there substantially reduces wear on the winding insulation.

List of results is not over, because the master work is being developed, the final version available from the author in January 2012.

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REFERENCES

1.Голунов Алексей Михайлович. Охлаждающие устройства масляных трансформаторов, М.— Л., издательство «Энергия», 1964. – 152 с.

2.Рожкова Л. Д., Козулин В. С. Электрооборудование станций и подстанций. — 2-е изд. — М.: Энергия, 1980.—600 с.

3.Инструкция по эксплуатации трансформаторов. — СПО ОРГРЭС, 1976.—107 с.

4.Голунов А. М., Мазур А. Л. Вспомогательное оборудование трансформаторов. — М.: Энергия, 1978.—143 с.

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