Construction
Operation & Maintenance
Substation
TEPCO have 1577 substations in 2005. We have built a variety of substations
depending on their purpose, supplying voltage, installing cost, and its supplying
area. 500kV large-scale underground type substation has been built for stable
and efficient supply for Tokyo metropolitan area.
Even though we operate a variety of substations and machineries, We have
achieved very low annual average electricity interrupting time. For stable
supply, we have introduced many up-to-date techniques. And we have organized
quality management system for substation design and construction (e.g. Guidelines
for installation of SF6 Gas Insulated Switchgears.). And we have developed
effective diagnostic/maintenance techniques for every machinery (e.g. dissolved
gas analysis and circuit breaker operation monitoring are employed).
We can offer the best solutions for substation construction/operation from
our technical experience.
Dissolved Gas Analysis for Transformer
Analysis of dissolved gases in insulation oil enables identification of electrical
fault (partial discharge, core overheating, or arcing) in transformers.
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An Example of the Partial Discharge in a Transformer
The air and effects of DGA
- To be applied for early detection of incipient fault in transformers.
- DGA result history produces useful information RCM program.
- No outage and complex procedures are required.
- Effective for reliability management of equipment & total cost suppression.
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