{"id":1872,"date":"2026-09-01T15:37:21","date_gmt":"2026-09-01T07:37:21","guid":{"rendered":"https:\/\/www.zishengelectric.com\/?post_type=product&p=1872"},"modified":"2026-11-06T18:22:57","modified_gmt":"2026-11-06T10:22:57","slug":"132kv-138kv-power-transformer","status":"publish","type":"product","link":"https:\/\/www.zishengelectric.com\/ru\/product\/132kv-138kv-power-transformer","title":{"rendered":"138kV \/ 140kV \/ 150kV Three-Phase Oil-Immersed Power Transformer"},"content":{"rendered":"

The 138kV \/ 140kV \/ 150kV Three-Phase Oil-Immersed Power Transformer is a high-voltage oil-immersed transformer designed for utility substations, power generation plants, industrial power networks, renewable energy projects, and large-scale transmission and distribution systems.<\/p>\n

\"Oil-immersed<\/figure>\n

It is engineered to provide reliable voltage transformation between high-voltage transmission networks and medium- or low-voltage distribution systems. Depending on the project, the transformer can be configured as a step-up or step-down transformer with customized capacity, voltage ratio, vector group, impedance, cooling system, tap changer and protection system.<\/p>\n

Voltage Configuration and Grid Interface<\/h3>\n

The HV winding is specified for 138kV, 140kV or 150kV. Select the MV\/LV winding voltage from the project bus arrangement, with 11kV, 13.8kV, 33kV, 34.5kV or a customized voltage as applicable. Confirm the complete winding-voltage schedule in the approved datasheet.<\/p>\n

Rated capacity can be designed from several MVA to tens or hundreds of MVA, depending on the application and grid requirements.<\/p>\n

\n

Technical Specifications<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Parameter<\/th>\nTypical Specification<\/th>\n<\/tr>\n<\/thead>\n
Product Type<\/td>\nHigh Voltage Oil-Immersed Power Transformer<\/td>\n<\/tr>\n
Rated Capacity<\/td>\nCustomized, typically 10\u2013200+ MVA<\/td>\n<\/tr>\n
Primary Voltage<\/td>\n138kV \/ 140kV \/ 150kV<\/td>\n<\/tr>\n
Secondary Voltage<\/td>\n11kV \/ 13.8kV \/ 33kV \/ 34.5kV \/ Customized<\/td>\n<\/tr>\n
Frequency<\/td>\n50Hz \/ 60Hz<\/td>\n<\/tr>\n
Phase<\/td>\nThree Phase<\/td>\n<\/tr>\n
Cooling Method<\/td>\nONAN \/ ONAF \/ OFAF \/ OFWF<\/td>\n<\/tr>\n
Winding Material<\/td>\nCopper \/ Aluminum<\/td>\n<\/tr>\n
Tap Changer<\/td>\nOLTC \/ Off-Circuit Tap Changer<\/td>\n<\/tr>\n
Vector Group<\/td>\nDyn11 \/ YNd11 \/ YNyn0 \/ Customized<\/td>\n<\/tr>\n
Neutral<\/td>\nSolid \/ Resistance \/ Reactance Grounded, as required<\/td>\n<\/tr>\n
Insulation Medium<\/td>\nMineral Oil \/ Ester Fluid<\/td>\n<\/tr>\n
Oil Preservation<\/td>\nConservator \/ Sealed Type<\/td>\n<\/tr>\n
Core Material<\/td>\nHigh-Grade Grain-Oriented Electrical Steel<\/td>\n<\/tr>\n
Frequency<\/td>\n50 \/ 60Hz<\/td>\n<\/tr>\n
Installation<\/td>\nOutdoor \/ Indoor<\/td>\n<\/tr>\n
Insulation Level<\/td>\nAccording to system voltage and applicable standard<\/td>\n<\/tr>\n
Standards<\/td>\nIEC 60076 Series \/ IEEE \/ ANSI or Customized<\/td>\n<\/tr>\n
Accessories<\/td>\nBuchholz Relay, PRD, OTI, WTI, MOG, etc.<\/td>\n<\/tr>\n
Monitoring<\/td>\nOptional Online Monitoring System<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Note: Final electrical parameters must be determined from the customer’s technical specification, grid code, utility requirements and transformer design.<\/p>\n

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Main Features<\/h2>\n

High-Voltage Transmission Capability<\/h3>\n

Designed for 138kV, 140kV and 150kV transmission and sub-transmission networks, with insulation systems engineered for high electrical stress and long-term reliability.<\/p>\n

High Efficiency<\/h3>\n

Optimized magnetic core and winding design reduces:<\/p>\n

    \n
  • No-load losses<\/li>\n
  • Load losses<\/li>\n
  • Operating costs<\/li>\n
  • Temperature rise<\/li>\n<\/ul>\n

    Strong Short-Circuit Capability<\/h3>\n

    The winding structure is mechanically reinforced to withstand the electromagnetic forces generated during short-circuit conditions.<\/p>\n

    Reliable Insulation System<\/h3>\n

    The insulation system is designed around:<\/p>\n

    Oil + Paper \/ Pressboard + Insulation Components + Controlled Electric Field Distribution<\/p>\n

    High-quality insulation materials and optimized field grading improve dielectric reliability.<\/p>\n

    Flexible Cooling<\/h3>\n

    Different cooling configurations can be selected according to transformer capacity and operating conditions:<\/p>\n

    ONAN \u2192 ONAF \u2192 OFAF \/ OFWF<\/p>\n

    OLTC Voltage Regulation<\/h3>\n

    An On-Load Tap Changer (OLTC) can be installed to regulate the output voltage while the transformer remains energized.<\/p>\n

    This is particularly useful for utility substations where grid voltage fluctuates during operation.<\/p>\n

    \n

    Transformer Construction<\/h2>\n

    1. Magnetic Core<\/h2>\n

    The core is manufactured from high-quality grain-oriented electrical steel.<\/p>\n

    Typical design features include:<\/p>\n

      \n
    • Step-lap core construction<\/li>\n
    • Low magnetic flux density<\/li>\n
    • Reduced no-load losses<\/li>\n
    • Low excitation current<\/li>\n
    • Reduced operating noise<\/li>\n
    • High mechanical stability<\/li>\n<\/ul>\n

      The core is carefully clamped to maintain mechanical integrity during transportation and operation.<\/p>\n

      \n

      2. High-Voltage Winding<\/h2>\n

      The HV winding is designed specifically for high-voltage electrical stress.<\/p>\n

      The design considers:<\/p>\n

        \n
      • Voltage distribution<\/li>\n
      • Inter-turn insulation<\/li>\n
      • Inter-layer insulation<\/li>\n
      • Axial and radial forces<\/li>\n
      • Short-circuit withstand capability<\/li>\n
      • Impulse voltage distribution<\/li>\n<\/ul>\n

        Depending on the capacity and voltage class, different winding structures can be selected.<\/p>\n

        \n

        3. Low-Voltage \/ Medium-Voltage Winding<\/h2>\n

        The secondary winding can be configured for common substation voltages such as:<\/p>\n

        11kV \u2022 13.8kV \u2022 33kV \u2022 34.5kV<\/p>\n

        Customized voltage ratios are also available.<\/p>\n

        \n

        4. Transformer Tank<\/h2>\n

        The transformer tank is manufactured from high-strength steel and designed to withstand:<\/p>\n

          \n
        • Vacuum conditions<\/li>\n
        • Pressure variations<\/li>\n
        • Transportation vibration<\/li>\n
        • Thermal expansion<\/li>\n
        • Electromagnetic forces<\/li>\n<\/ul>\n

          The tank can be subjected to leakage and pressure testing before shipment.<\/p>\n

          \n

          Tap Changer<\/h2>\n

          For 138kV \/ 140kV \/ 150kV power transformers, an OLTC can be provided for automatic voltage regulation.<\/p>\n

          Typical options include:<\/p>\n

            \n
          • \u00b110%<\/li>\n
          • \u00b112.5%<\/li>\n
          • \u00b115%<\/li>\n<\/ul>\n

            The actual tap range and number of positions are customized according to the grid specification.<\/p>\n

            The OLTC can be integrated with:<\/p>\n