66/110/220/330kV Transformer

★★★★★ Engineered for reliable performance

High efficiency and low operating loss
Reliable insulation and temperature control
Low noise and long service life
Designed to IEC / IEEE requirements

Customization:Voltage, capacity and accessories

Quality:Factory tested before shipment

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110kV Transformers

Concepts: 110kV transformers are high-voltage (HV) step-down units typically operating in regional transmission and sub-transmission networks. They bridge the gap between high-voltage bulk power grids and lower-voltage industrial or urban distribution systems (such as 35kV or 10kV).
Applications: Widely used as step-down substations to supply power to medium-to-large industrial facilities, urban substations, and regional load centers. They also serve as interconnection transformers in moderately sized generation plants.
Applicable Scope: Urban and suburban power grids, large manufacturing plants, chemical processing facilities, heavy commercial complexes, and regional sub-transmission substations.

220kV Transformers

Concepts: 220kV transformers function as primary backbone components in regional and inter-provincial power transmission grids. They feature high insulation levels, large capacity ratings, and advanced cooling systems designed to handle substantial bulk power transfers over medium to long distances.
Applications: Utilized in major regional step-down substations to convert ultra-high or high-voltage power down to 110kV or 66kV levels. They are crucial for stabilizing grid voltage, managing heavy industrial loads, and integrating conventional power plants (thermal, hydro, or large wind/solar farms).
Applicable Scope: Provincial backbone power grids, metropolitan ring transmission networks, large-scale renewable energy collection stations, and heavy industrial economic development zones.

330kV Transformers

Concepts: 330kV transformers are specialized extra-high-voltage (EHV) units engineered primarily for transmission networks characterized by high altitudes, long-distance power conveyance, and specific geographic topologies.
Applications: Deployed to transmit bulk electrical energy efficiently over vast geographic expanses with minimal line losses. They handle heavy interchange between major regional grids and step down EHV power to lower transmission tiers (such as 220kV or 110kV).
Applicable Scope: Predominantly utilized in specific regional power grids—notably in Northwest regions and high-altitude areas with extensive transmission distances—as well as major inter-regional tie-lines and ultra-large-scale generation integration hubs.

330kV Oil-Immersed Three-Phase Double-Winding Off-Circuit Tap-Changing Power Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Short-circuit impedance (%)	No load losses (kW)	On load losses (kW)
90000	345/363	±2×2.5	10.5	YNd11	0.35	14~15	37	247
120000			10.5		0.35		47	306
150000			10.5		0.33		56	362
180000			13.8		0.30		64	415
240000			15.75		0.27		80	515
360000			18		0.27		109	722
370000			20		0.24		111	736
400000			20		0.24		118	780
720000			20		0.16		183	1212

330kV Oil-Immersed Three-Phase Three-Winding Off-Circuit Tap-Changing Power Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Medium Voltage (MV)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Short-circuit impedance (%)	No load losses (kW)	On load losses (kW)
90000	330/345	±2×2.5	121	10.5/13.8/15.75	YNyn0d11	0.37	HV~MV: 24~26 HV~LV: 14~15 MV~LV: 8~9	42	302
120000	330/345	±2×2.5	121	10.5/13.8/15.75	YNyn0d11	0.37		53	374
150000	330/345	±2×2.5	121	10.5/13.8/15.75	YNyn0d11	0.34		63	442
180000	330/345	±2×2.5	121	10.5/13.8/15.75	YNyn0d11	0.34		72	507
240000	330/345	±2×2.5	121	10.5/13.8/15.75	YNyn0d11	0.32		89	629

220kV Oil-Immersed Three-Phase Double-Winding Off-Circuit Tap-Changing Power Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Short-circuit impedance (%)	No load losses (kW)	On load losses (kW)
31500	220/242	±2×2.5	6.3/6.6/10.5	YNd11	0.45	12~14	15	115
40000		±2×2.5		YNd11	0.45	12~14	18	134
50000		±2×2.5		YNd11	0.42	12~14	21	161
63000		±2×2.5		YNd11	0.42	12~14	25	188
75000		±2×2.5	10.5/13.8	YNd11	0.38	12~14	29	213
90000		±2×2.5	10.5/13.8	YNd11	0.35	12~14	34	246
120000		±2×2.5	10.5/13.8	YNd11	0.35	12~14	41	304
150000		±2×2.5	10.5/13.8/15.75/18/20	YNd11	0.32	12~14	49	360
160000		±2×2.5		YNd11	0.31	12~14	51	378
180000		±2×2.5		YNd11	0.29	12~14	56	413
240000		±2×2.5		YNd11	0.26	12~14	70	484

220kV Oil-Immersed Three-Phase Three-Winding Off-Circuit Tap-Changing Power Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Medium Voltage (MV)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Short-circuit impedance (%) - Boost	Short-circuit impedance (%) - Decompression	No load losses (kW)	On load losses (kW)
31500	220/230/242	±2×2.5		6.3/6.6/10.5/213	YNyn0d11	0.45	HV~MV: 22~24 HV~LV: 12~14 MV~LV: 7~9	HV~MV: 12~14 HV~LV: 22~24 MV~LV: 7~9	18	138
40000				6/37/38.5		0.40			21	165
50000				6/37/38.5		0.35			24	194
63000				6/37/38.5		0.35			29	231
90000			69/115/121	10.5/13.8/21/36 37/38.5		0.31			37	300
120000			69/115/121	10.5/13.8/21/36 37/38.5		0.31			46	369
150000				10.5/13.8/15.75 21/36/37/38.5		0.26			55	438
180000						0.26			62	500
240000						0.22			72	616
300000						0.19			91	726

220kV Oil-Immersed Three-Phase Double-Winding On-Load Voltage Regulating Power Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Short-circuit impedance (%)	No load losses (kW)	On load losses (kW)
31500	220/230	±4×1.25 ±6×1.25 ±8×1.25	6.3/6.6/10.5/21/36/37/38.5	YNd11	0.46	12~14	17	115
40000			6.3/6.6/10.5/21/36/37/38.5		0.46	12~14	20	134
50000			6.3/6.6/10.5/21/36/37/38.5		0.42	12~14	24	161
63000			6.3/6.6/10.5/21/36/37/38.5		0.42	12~14	28	188
90000			10.5/21/36/37/38.5		0.36	12~14	35	246
120000			10.5/21/36/37/38.5		0.36	12~14	43	304
150000			10.5/21/36/37/38.5		0.33	12~14	51	360
180000			10.5/21/36/37/38.5		0.30	12~14	59	413
120000			66/69		0.36	12~14	45	303
150000			66/69		0.33	12~14	53	355
180000			66/69		0.30	12~14	62	406
240000			66/69		0.24	12~14	77	504

220kV Oil-Immersed Three-Phase Three-Winding On-Load Voltage Regulating Power Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Medium Voltage (MV)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Impedance voltage (%)	No load losses (kW)	On load losses (kW)
31500	220/230	±4×1.25 ±6×1.25 ±8×1.25		6.3/6.6/10.5/21/36/37/38.5	YNyn0d11	0.50	HV~MV: 12~14 HV~LV: 22~24 MV~LV: 7~9	19	138
40000						0.48		23	165
50000			69			0.48		26	194
63000			69			0.44		31	231
90000			69/115/121	(Taps / N/A)		0.35		40	300
120000				10.5/21/36/37/38.5		0.35		51	369
150000						0.31		59	438
180000						0.31		68	538
240000						0.28		85	667

110kV Oil-Immersed Three-Phase Double-Winding Unexcited Voltage Regulating Power Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Impedance voltage (%)	No load losses (kW)	On load losses (kW)
6300	110/151/121	±2×2.5	6.3/6.6/10.5	YNd11	0.50	10.5	4.1	32
8000					0.50	10.5	4.9	38
10000					0.46	10.5	5.8	45
12500					0.46	10.5	6.8	53
16000					0.43	10.5	8.3	65.7
20000					0.43	10.5	9.7	79
25000					0.40	10.5	11.4	94
31500					0.38	10.5	13.5	111
40000					0.36	10.5	16.2	133
50000					0.34	10.5	19.4	158
63000					0.30	10.5	22.9	187
75000			13.8/15.75/18/21		0.26	12~14	26.0	212
90000			13.8/15.75/18/21		0.24	12~14	29.9	245
120000			13.8/15.75/18/21		0.22	12~14	37.3	303
150000			13.8/15.75/18/21		0.19	12~14	44.1	359
180000			13.8/15.75/18/21		0.16	12~14	49.5	411

110kV Oil-Immersed Three-Phase Three-Winding Unexcited Voltage Regulating Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Medium Voltage (MV)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Short-circuit impedance (%) - Boost	Short-circuit impedance (%) - Decompression	No load losses (kW)	On load losses (kW)
6300	110/115/121	±2×2.5	36/37/38.5	6.3/6.6/10.5/21	YNyn0d11	0.53	HV~MV: 17.5~18.5 HV~LV: 10.5 MV~LV: 6.5	HV~MV: 10.5 HV~LV: 17.5~19 MV~LV: 6.5	4.9	40
8000						0.50			5.8	48
10000						0.47			6.9	56
12500						0.45			8.1	67
16000						0.42			9.8	81
20000						0.42			11.6	95
25000						0.38			13.5	113
31500						0.38			16.2	134
40000						0.35			19.1	161
50000						0.35			22.9	192
63000						0.32			27.1	230

110kV Oil-Immersed Three-Phase Double-Winding On-Load Voltage Regulating Power Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Impedance voltage (%)	No load losses (kW)	On load losses (kW)
6300	110	±4×1.25 ±6×1.25 ±8×1.25	6.3/6.6/10.5/21	YNd11	0.51	10.5	4.4	32
8000	110				0.51	10.5	5.3	38
10000	110				0.47	10.5	6.2	45
12500	110				0.47	10.5	7.4	53
16000	110				0.44	10.5	8.9	66
20000	110				0.44	10.5	10.6	79
25000	110				0.41	10.5	12.5	94
31500	110				0.41	10.5	14.9	111
40000	110				0.37	10.5	17.8	140
50000	110				0.37	10.5~18	21.0	175
63000	110				0.34	10.5~18	25.0	209

110kV Oil-Immersed Three-Phase Three-Winding On-Load Voltage Regulating Power Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Medium Voltage (MV)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Impedance voltage (%)	No load losses (kW)	On load losses (kW)
6300	110	±4×2.5 ±6×2.5 ±8×2.5	36/37/38.5	6.3/6.6/10.5/21	YNyn0d11	0.61	HV~MV: 10.5 HV~LV: 17.5~19 MV~LV: 6.5	5.3	40
8000	110					0.61		6.3	48
10000	110					0.57		7.5	56
12500	110					0.57		8.9	67
16000	110					0.54		10.6	81
20000	110					0.54		12.5	95
25000	110					0.50		14.9	113
31500	110					0.50		17.7	134
40000	110					0.46		21.2	161
50000	110					0.46		25.0	192
63000	110					0.42		29.8	230

66kV Oil-Immersed Three-Phase Double-Winding Unexcited Voltage Regulating Power Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Impedance voltage (%)	No load losses (kW)	On load losses (kW)
3150	63/66/69	±5	6.3/6.6/10.5	YNd11	0.70	8	2.2	20.7
4000					0.64	8	2.6	24.6
5000					0.54	8	3.1	27.6
6300		±2×2.5			0.48	8	4.0	30.8
8000					0.48	8	4.9	36.5
10000					0.45	8	5.8	43.0
12500					0.45	8	6.8	51.1
16000					0.42	8	8.3	62.8
20000					0.42	9	9.7	76.1
25000					0.38	9	11.4	90.0
31500					0.35	9	13.5	108.0
40000					0.35	9	16.2	126.9
50000					0.32	9	19.4	150.3
63000					0.29	9	22.9	178.2

66kV Oil-Immersed Three-Phase Double-Winding Unexcited Voltage Regulating Power Transformer

Rated capacity(kVA)	Rated voltage - High Voltage (HV)	Tapping range (%)	Rated voltage - Low Voltage (LV)	Vector group	No load current (%)	Impedance voltage (%)	No load losses (kW)	On load losses (kW)
3150	63/66/69	±5	6.3/6.6/10.5	YNd11	0.70	8	2.2	20.7
4000					0.64	8	2.6	24.6
5000					0.54	8	3.1	27.6
6300		±2×2.5			0.48	8	4.0	30.8
8000					0.48	8	4.9	36.5
10000					0.45	8	5.8	43.0
12500					0.45	8	6.8	51.1
16000					0.42	8	8.3	62.8
20000					0.42	9	9.7	76.1
25000					0.38	9	11.4	90.0
31500					0.35	9	13.5	108.0
40000					0.35	9	16.2	126.9
50000					0.32	9	19.4	150.3
63000					0.29	9	22.9	178.2

High Efficiency

Optimized electromagnetic design reduces operating losses.

Low Noise

Controlled core construction and structural vibration.

Long Life

Reliable insulation and thermal performance.

Quality Assured

Complete inspection and factory testing.

66/110/220/330kV Transformer

110kV Transformers

220kV Transformers

330kV Transformers

High Efficiency

Low Noise

Long Life

Quality Assured

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