220kV power transformer

Specifications

220kV power transformer
1) CTQC,ISO9001,ISO14001,CE. KEMA, ECSI
2) Apply for IEC,GB,ANSI
3) Up to 230kV,240MVA

220KV power transformer detailed information 

Manufacture:

Core: effectively upgrade transformer’s no-load performance by below methods:

1)    The core is made of high-permeable grain-orientated top quality cold-rolled silicon sheet and the material is cut with advanced Germany Geoge GmbH automatic shear line with the cut burs controlled within 0.02mm.

2)    The silicon sheet fabrication adopts “no-upper yoke lapped’ technology and all lapped joints of the silicon sheet are 45 full-miters. The laminated  core sheets are integrally pressed and adhered with epoxy resin to make the three –leg two-yoke core a strong and flat integral one with good verticality precision, this effectively improves no-load performance and reduces noises.

3)    Bracing plates are used as support between coil leg and inner coil. The iron yoke is tied with epoxy resin-impregnated glass fiber band, and the lower section of oil tank is tightened with counter-pressure bolts. The upper iron and the upper section of oil tank are fixed at three locations. Hence the body inside the oil tank can withstand the vibration during transportation without any shift.

 Winding:

1)    The high-voltage (HV) coil adopts an interleaved-continuous structure to improve the voltage characteristics under impact voltage and make voltage evenly distributed. All stays and pads are chamfered to keep highly reliable insulation.

2)    In the transformer winding there is a zigzag oil guide structure so as to fully cool all areas inside the winding, lower the temperature rise of the winding and the hot points of the winding and prolong the service life of insulation. The HV and MV regulation system are independently provided with voltage-regulating winding to balance the ampere turn of each winding,  effectively lower the axial electrodynamic force generated at short-circuit of transformer and improve abrupt short-circuit withstanding capacity.

3)    The winding adopts radial “0” margin designed, between the core and the paper sleeve of LV winding, and between the LV, HV, voltage-regulating windings, as well as before insertion of stays and shroud plate they are fully dried and tightly matched to ensure extremely good compactness and concentricity of the entire winding.

Oil tank and accessories

1)  The tank wall adopts wide steel sheet, which will be folded into corrugated structure without splicing, in this way welds are decreased and mechanical strength is enhanced, meanwhile, the corrugated wall has diverging effect, and thus plays a role in decrease of noise. The routing troughs and control cabinets of the secondary circuit are all made of stainless steel, so the entire transformer has a simple and good looking.

2)  All sealing surface use quality sealing material and are precision-machined.

3)  On the edge of the tank there are double sealing grooves, and the outer sealing material is used to shade the atmosphere and ultra-ray to protect the inner sealing being damaged, thus at utmost prolonging service life and enhancing reliability of the seal.

Main technical parameters for three-phase two winding on-load-tap-changing power transformer

Rated power (kVA)	High Voltage (kV)	H.V Tap range	Low Voltage (kV)	Connection Symbol	Short-Circuit Impedance (%)	No-load Loss (kW)			On-Load Loss (kW)			No-load Current (%)
						9 Type	10 Type	11 Type	9 Type	10 Type	11 Type
31500	220 242	±8×1.25% ±8×1.5%	6.3,6.6, 10.5,11, 20,34.5, 35,37, 38.5,66, 69	YNd11	12~14	38	34	30	135	128	128	0.7
40000						45	41	36	157	149	149	0.63
50000						54	49	43	189	180	180	0.56
63000						63	57	50	220	209	209	0.56
90000						80	72	64	288	274	274	0.49
120000						99	89	79	346	329	329	0.49
150000						116	104	93	405	385	385	0.42
180000						135	122	108	468	445	445	0.42

Main technical parameters for three-phase two winding non-excitation-tap-changing power transformer

Rated power (kVA)	High Voltage (kV)	H.V Tap range	Low Voltage (kV)	Connection Symbol	Short-Circuit Impedance (%)	No-load Loss (kW)			On-Load Loss (kW)			No-load Current (%)
						9 Type	10 Type	11 Type	9 Type	10 Type	11 Type
31500	220 242	±8×1.25% ±8×1.5%	6.3,6.6, 10.5,11, 13.8,15.75 20,35, 38.5,	YNd11	12~14	35	135	32	128	28	128	0.7
40000						41	157	37	149	33	149	0.7
50000						49	189	44	180	39	180	0.65
63000						58	220	52	209	46	209	0.65
75000						67	250	60	238	54	238	0.6
90000						77	288	69	274	62	274	0.55
120000						94	345	85	328	75	328	0.55
150000						112	405	101	385	90	385	0.5
160000						117	425	105	404	94	404	0.49
180000						128	459	115	436	102	436	0.46
240000						160	567	144	539	128	539	0.42

plant and test lab

packing and delivery