| Brand | Rockwell |
| Model NO. | 11kV Three-Phase Oil-Immersed Grounding Transformer |
| Rated frequency | 50/60Hz |
| Rated capacity | 500kVA |
| Series | JDS |
Description
Earthing transformers are classified as standard reactors. An earthing transformer (neutral coupler) is a three-phase transformer connected to the power system to provide a neutral connection for earthing, either directly or via impedance. The earthing transformers may, in addition, supply a local auxiliary load.
During single-phase faults, the reactor limits the fault current in the neutral, and the restoration of the power line is improved. According to the IEC 60076-6 standard, the neutral-earthing reactor is connected between the neutral of a power system and the earth to limit the line to earth current under system earth fault conditions to the desired value.
The earthing transformer creates a neutral point for a network. ZN connection is usually applied. Z connection provides linear and specified zero sequence impedance. YN + d can also be applied.
Features
Functional Uniqueness:
Constructing an Artificial Neutral Point: Provides a reliable neutral point connection for systems with ungrounded or high-impedance grounded neutrals (such as IT systems and resonant grounded systems).
Grounding Path Management: The neutral point can be directly grounded or grounded via a reactor/resistor, precisely limiting single-phase ground fault current (in line with IEC 60076-6).
Fault Current Control:
Suppressing Fault Current: Limits the ground fault current to a safe valuev by connecting a neutral reactor in series, preventing equipment damage.
Accelerating System Recovery: Reducing the magnitude of the fault current helps the arc self-extinguish, shortens power outage duration, and improves power supply continuity.
Winding Connection Methods:
ZN Type (Zigzag Connection): A mainstream design that provides linear zero-sequence impedance, with strong magnetic circuit balance and anti-saturation capability.
YN+d (Star + Delta): The secondary delta winding can supply auxiliary loads (doubling as a station service transformer function).
Controllable Zero-Sequence Impedance: Impedance values can be customized to ensure precise matching with the system protection strategy.Safety and Standard Compliance:
Following IEC 60076-6: Regulates the temperature rise, insulation, and short-circuit withstand capability of neutral reactors.
Overvoltage Suppression: Limits transient overvoltages caused by ground faults, protecting equipment insulation.
Main Technical Parameters
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22kV Oil-Immersed High-Voltage Side-Mounted Grounding Transformer
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Grounding/earthing TransformerUp to 36kV
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66kV Three Phase Oil-Immersed Earthing Transformer
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6/10kV Three - phase dry - type grounding/earthing transformer
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Three - phase 11kV 22kV grounding/earthing transformers
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20kV Three Phase Oil-Immersed Earthing Transformer
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35kV Dry Type Grounding Transformer Cast Resin 3 Phase
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