| Brand | ROCKWILL |
| Model NO. | 35kV Dry Type Grounding Transformer Cast Resin 3 Phase |
| Rated capacity | 400kVA |
| Phases | 三相 |
| Series | DKSC |
Overview
Rockwill Zigzag (Z-Type) Grounding Transformers provide a reliable artificial neutral grounding solution for power systems where the neutral point is unavailable, such as delta-connected or ungrounded star systems. These specialized transformers create a stable neutral point for connecting arc suppression coils (Petersen coils) or neutral grounding resistors, ensuring safe and effective system grounding.
Additionally, Rockwill grounding transformers can be equipped with a secondary winding to supply auxiliary power, offering a cost-effective alternative to separate station transformers.
Key attributes
Key Applications
Substations and distribution networks (35kV and below)
Industrial power systems requiring a neutral grounding point
Renewable energy plants (wind/solar farms) with ungrounded sources
Main Technical Specifications
Rated Capacity: 100kVA to 5500kVA
Rated Voltage: Up to 35kV
Insulation Class: Class F (compliant with IEC 60076)
Connection Type: Zigzag (Z-Type) for optimal zero-sequence performance
Zero-Sequence Impedance: Low impedance (~10Ω) for efficient fault current handling
Key Features & Benefits
Advanced Zigzag Winding Design – Unlike conventional transformers, Rockwill’s Z-Type configuration ensures zero-sequence flux circulates within the core, minimizing impedance and enhancing grounding performance.
Full-Capacity Arc Suppression Support – Compatible with 90-100% rated capacity arc suppression coils, far exceeding the 20% limit of standard transformers.
Dual-Purpose Functionality – Optional secondary winding allows the transformer to supply station power, reducing the need for additional equipment.
Dry-Type, Cast Resin Construction – Maintenance-free, flame-resistant, and suitable for harsh environments.
High Efficiency & Reliability – Engineered for stable operation under fault conditions, preventing magnetic saturation.
IEC 60076 Compliant – Manufactured to international standards for global reliability.
Why Choose Rockwill?
Rockwill grounding transformers deliver superior performance, safety, and cost savings by combining neutral grounding and auxiliary power supply in a single unit. Their optimized design ensures enhanced system protection, reduced downtime, and lower installation costs—making them the ideal choice for modern power systems.
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