孟加拉国 50MVA 132kV 电力变压器英文招标书Word格式文档下载.docx

1、Ghorashal Power Station.a. 132/33/11KV, ONAN rating 25/25/18MVA, ONAF rating 50/50/35MVA, out door mounting, 3 phase. 50 Hz, uniform insulation. 132 4x2 % KV （HV taps on-load operating 9 Nos. of taps）, mineral oil immersed equipped with BCT. The supply of transformer will also include suitable size

2、（size will be confirmed during detail Engineering） of MS rail for placing of transformer on foundation. During submission of the bid the technical data requirement of BPDB shall be fully complied by the bidder. In case of any deviation observed in bidders technical data from Users technical data, th

3、e bidders bid will be declared non-responsive. The bidder will provide 1（one） engineer for expert service during installation, testing and commissioning of the transformer for 15 days. The following specification are prepared based on the existing one with a view to procure an identical one because

4、both will run in Parallel. Successful Bidder may visit Ghorasal power station for taking necessary data form existing one externally by measurement for detail engineering.b. The insulation value of HV /MV/ LV sides are:（i） Highest system voltage : 145 / 36/ 12kV（ii） Basic insulation Level （BIL） : 65

5、0 / 170/ 75 kV（iii） Power frequency with stand Voltage （1min） : 275/70/28 kV.The Insulation level of HV & MV Neutral Bushing shall be same as Phase Bushings.c. The HV bushing and bushing for the neutral shall be capacitor type, porcelain being brown glazed. The BCT fitted in the neck of each bushing

6、 shall have 2 core & 4 tapping of each core. The ratio, accuracy class and burden of BCT are as follows:HV BCT:（i） 1st core:No of tapping: 4 1st tap: 400/1A,3P20, 20VA.2nd tap: 600/1A, 3P30,30VA.3rd tap : 750/1A, 3P30, 75VA.4th tap : 1000/1A, 1P30, 30VA.（ii） 2nd core: 4 400/1A, class 0.2, 20VA.2nd t

7、ap : 600/1A, class 0.2, 30VA. 750/1A, class 0.2, 75VA. 1000/1A, class 0.2, 30VA.Bushing for the neutral of HV side:（1） 1st core: 200/5A, 10P15, 15VA. 300/5A, 3P10,10VA. 400/5A, 3P20, 20VA. 600/5A, 3P30, 30VA.（ii）2nd core:Same as 1st core:d. The MV bushing and bushing for the neutral may be of capaci

8、tor type or porcelain type with outside glazed of brown porcelain. The BCT fitted in the neck of each bushing shall have 2 core &MV BCT: 600/5A, 3P30,30VA. 750/5A, 3P30, 75VA. 1000/5A, 1P30, 30VA.Same as 1st core.（I） 1st core: 1st tap:e. The LV bushing may be of capacitor type or porcelain type with

9、 outside glazed of brown porcelain. No CT required for the bushing.f. Values of resistance reactance of the transformer shall not be deviated by more than 2% （two percent） of the BPDBS requirements and the core & copper loss of transformer shall not exceed 5% （five percent） of BPDBS requirements. Th

10、e above-mentioned values are the tolerance values to be maintained during factory testing if exceeds the transformer will be rejected.The impedance voltage, core loss and copper loss of the transformer shall be: Impedance voltage at HV-132-kV, MV 33, kv at 50 MVA and at 750C:Between HV and MV windin

11、g = 11.568%Between HV and LV winding = 19.443%Between MV and LV winding = 6.051%Core loss at nominal voltage, normal ratio and at rated frequency = 37.914 kW.Total excitation current = 0.251%Full load copper loss at nominal voltage （HV=132kV, MV=33kV） normal ratio at rated frequency and at 750C:50MV

12、A HV and MV winding = 271.712 KW35MVA HV and LV winding = 170.854 KW35MVA MV and LV winding = 130.092 KWg. The winding shall be capable of withstanding:14.3 times base current for 5 seconds.16.6 times base current for 4 seconds.20.0 times base current for 3 seconds.25.0 times base current for 2 seco

13、nds.The winding shall be of electrolytic copper, free from burs and splinter. Paper shall be used for conductor insulation.h. The insulating oil shall meet all requirements as defined by NEMA standard/ B.S. shall be chemically stable, free from acidity and other corrosive ingredients and shall posse

14、s high dielectric strength. Oil for first filling shall be shipped in non-returnable drums. 10% of the quantity required for a transformer is to be supplied in addition due to usual losses during installation centrifuging etc.i. The transformer tank shall be of welded construction fabricated from hi

15、gh tensile steel plate and shall be designed to withstand full vacuum.j. The transformer shall have air seal cell type oil conservator tank （the oil surface is completely isolated from the atmosphere by installing an oil resistant rubber cell in the interior of the conservator） at the top. Transform

16、er will be provided with 2 separate conservators （1for main tank and another for On load Tap Changer）, which will be having provision for mounting separate MOLG. One part to be connected with transformer main tank through Buchholtz Relay （with cocks on both side） and the other part with OLTC tank th

17、rough another gas Relay （with cock either side）. Both will have oil level indicate （visual） with contacts for medicating “LOW OIL LEVEL” in the control panel.k. Pressure Release Devices for both Main Tank and OLTC Tank shall be providedl. Silica gel Breather with glass window shall be provided for b

18、oth halves of the conservator lank.m. The On-load Tap Changer operating device shall be equipped with local （manual and electrical） and remote electrical operating device with appropriate interlocking. The OLTC motor shall be 3-phase 400 V operating type. The mechanical position indication shall be

19、there both at the tap changer as well as on the operating device. Contacts Arrangements shall be there for remote position indicator （by digital display system） of the tap. Appropriate glands for the entry of control cable shall be provided.n. Sufficient Cooling Fans （3-phase, 400V, 50 HZ） of adequa

20、te capacity shall be fitted on the body of the transformer for cooling purpose to achieve the ONAF rating over the average ambient temperature of 400C. There shall be a control device in weather proof housing fitted on the body of the transformer and equipped with control relay operated by sensing d

21、evice of oil temperature inside the transformer and operate requisite No. of fans. Beside there shall be manual switching device of cooling fans.o. The Radiators shall be in banks, which can be filled with or removed from the beds of transformer tank. Sufficient radiators shall be provided to achiev

22、e the ONAN rating at average ambient temperature of 400C. Each bank of radiator must have two stop valve one of which should be fixed at the top and the other at the bottom.p. Beside the main components of the transformer the other features and accessories to be associated which are as follows:（i） I

23、nspection hole with cover.（ii） Manhole.（iii） Nameplate with complete diagrams and main speculations.（iv） Upper and lower oil valves oil sampling valve and drain valve.（v） Ladder to climb up to top with barrier at the bottom.（vi） Thermometer for sending oil and winding temperature and display: WTI sh

24、all have two contacts among them one will be used for alarm circuit and other will be suitable for intercropping of HV and MV/LV Circuit Breaker.（vii） All HV （132 KV） terminals shall be provided with appropriate connecting clamps to be connected with 636 MCM ACSR conductors. The LV （33 KV） terminals

25、 shall have also connecting clamps appropriate for being connected with one 636 MCM ACSR conductor. The neutral terminal shall have connecting clamps to be connected with 2/0 HDBS wire. The size of conductors may be changed during approval stage. （viii） There shall be four wheels （flange type） suita

26、ble for mounting on rails and to carry the transformer as a whole.（ix） The transformer shall have at least two grounding terminals on its body.All ferrous parts of the transformer shall be galvanized or painted with appropriate paints of MUNSELL NO-5 Y7/1. Transformer with maximum shipping height （n

27、ot exceeding 11 feet） will be preferred.q. One set of extra gaskets and one set bushing of each type is to be supplied with the transformer lot without extra cost.r. The loss capitalization of power transformer will be done by the following formula for evaluation.C = A + 25650 X FL.Where:C = Capital

28、ized cost in Taka.A = Quoted C&F cost in Take.FL = Total consumption of cooling fans in KW.s. Make and Model of Tap Changer: The transformer will be fitted with MR, Germany make On Load Tap Changer （M111 500 Y Model）t. Color of Finish Paint: All the existing transformers at Ghorashal are having exte

29、rnal Aluminum finish Paint, The same will be provided for the new transformer.u. Termination of tertiary: Tertiary （11KV） winding will be brought out side to tank top after closing delta winding inside through 3 external bushings. （Bushings will be supplied extra）v. Control scheme of Tap Changer: On Load Tap Changer control scheme of new transformer will be suitable for individual operation of transformer from Control room. Master Follower, Individual operation facility will be provided in this unit.w. Terminal connector: Transformer will be supplied with terminal connector