Energy Storage Specialized Oil-Immersed Transformers

Energy Storage Specialized Oil-Immersed Transformers

Structural Advantages:

1. The transformer core adopts a quasi-circular cross-section, which results in a more compact structure and significantly improved short-circuit withstand capability compared to traditional elongated designs. It successfully passed the short-circuit withstand test at the Shenbei Substation.

2. High-density electrical grade laminated wood is used for transformer core clamping components, creating a more compact overall structure and providing some suppression of stray losses caused by leakage magnetic fields.

3. By altering the internal body positioning and switch installation method, the high-voltage raising platform has been redesigned to have a structure without hand holes, reducing the risk of oil leakage.

Quality Control Advantages:

1. The transformers consider the losses caused by harmonic currents, avoiding exceeding the temperature rise limits of the transformer oil and windings. Additionally, it takes into account the increased capacity demand resulting from harmonic currents to ensure the transformer’s service life.

2. For products of the same model and batch, 10% (>1 unit) are selected for lightning impulse tests and temperature rise tests to further ensure the product’s electrical and mechanical performance.

3. While the national standard GB/T 1094.3 does not specify partial discharge tests for 35kV oil-immersed power transformers, from a product quality perspective, the assessment has been intensified. According to the testing method specified in GB/T 7354, partial discharge tests are conducted on each new energy transformer to ensure that the partial discharge level is <50pC at 1.2Ur and ≤100pC at 1.4Ur (Ur is the rated voltage of the transformer).

Standards Compliance:

GB/T 1094.1 Power Transformers – Part 1: General

GB/T 1094.3 Power Transformers – Part 3: Insulation Levels, Insulation Tests, and External Clearances in Air

GB/T 1094.5 Power Transformers – Part 5: Ability to Withstand Short-Circuit

GB/T 1094.14 Power Transformers – Part 16: Transformers for Wind Turbine Generators

GB/T 6451 Technical Parameters and Requirements for Oil-Immersed Power Transformers

GB20052 Limits and Grades for Energy Efficiency of Power Transformers

IEC60076-20 Power Transformers – Part 20: Energy Efficiency.

Production scene diagram of transformer workshop