Electrical substations are a part of an electricity generation, transmission and distribution system where voltage is transformed from high to low or in reverse using transformers. The general functions of a substation may include:
- Voltage transformation
- Connection point for transmission lines
- Switchyard for network configuration
- Monitoring point for control center
- Protection of power lines and apparatus
There are various kinds of substations namely: Transmission substations, distribution substations, collector substations, switching substations and other. Their design can vary vastly though all use similar components, all of which are prone to corona and arcing activity, that include:
- Supporting structures
- Disconnect elements primary and secondary, such as open-air fused switches, circuit switchers or, circuit breakers, reclosers
- Capacitor banks
The integrity of conductors’ conditions, buswork and hardware conditions, porcelain post, pin as well as bell insulators conditions, polymer insulators’ conditions, switch gears, transformers etc., can be checked with Ofil’s corona cameras. In fact, Ofil’s corona cameras can efficiently identify many of the most common failure modes of those components without outages.
Inspection for corona sources is important throughout the life time of substations, and in particular during commissioning.
Ofil’s daytime corona cameras enable pinpointing sources of corona partial discharge and designate thereby faulty components and components in deteriorating stages.
Using Ofil’s systems in substations can prevent outages and flashovers and reduces significantly the maintenance costs.
Corona cameras can denote
- Degradation of Polymer insulators
- Contamination – coastal salt; industrial vapors and dusts; cement dust; highway road-salt; tire dust and car emissions; agricultural dusts and fertilizers
- Cracked porcelain insulators
- Rusted cement and metal caps & pins on porcelain insulators.
- RFI, TVI and audio noise sources lead to customer complaints
- Wrong design and improper installation, that may lead to mechanical and electrical failure, of: hardware such as corona ring, conductors ADSS etc…
- Shorted bells
- Loose hardware such as: spacers, slices, clamps etc.
- Corona on capacitors
- Crowded inspection objects
- Dangerous location
- Inspection of nearby objects