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Dynamic behavior of power-frequency arc in transformer oil
Zeyuan Mu1, Chenglong Wang1, Yang Meng1
1State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049, China.
The Review of Scientific Instruments
|May 19, 2025
Summary
Internal arcing faults in transformers generate shock waves and arc plasma dynamics. This leads to significant pressure rise and potential tank explosions due to increased gas generation.
Area of Science:
- Electrical Engineering
- Plasma Physics
- Materials Science
Background:
- Transformer tank explosions from internal arcing faults are a significant concern.
- Existing research primarily focuses on arc-induced gas generation and bubble dynamics, neglecting arc plasma behavior.
Purpose of the Study:
- To analyze the dynamic behavior of arc plasma during formation and evolution.
- To investigate the multi-feature electrical-optical-mechanical characteristics of power-frequency arcs.
Main Methods:
- Established a synchronized observation platform for multi-feature analysis of power-frequency arcs.
- Analyzed arc formation, shock wave generation, and arc-induced bubble dynamics.
Main Results:
- Arc formation generates high-amplitude, narrow-width shock waves.
- Shock wave reflection and bubble fluctuation dictate oil pressure.
- Arc evolution involves gas heating, arc elongation, and increased arc voltage.
- Bubble deformation drives increased gas velocity, further elongating the arc and voltage.
- Arc elongation amplifies energy and gas generation per unit energy, escalating pressure.
Conclusions:
- The study elucidates the critical role of arc plasma dynamics in transformer internal arcing faults.
- Understanding shock waves and bubble fluctuations is key to predicting pressure rise.
- The dual effect of arc elongation on energy and gas generation drives significant pressure increases, highlighting explosion risks.
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