Medium Voltage Substations
Medium Voltage Substations
The electrical power supply of a customer is provided by ΔΕΔΔΗΕ’s grid. The maximum low voltage power for a consumer is 250kVA (Type 7 ΔΕΔΔΗΕ). Often (and mainly inside residential areas) the maximum low voltage power for a customer is only 135kVA (Type 6). When bigger demands occur, a Medium Voltage Substation is needed so the customer can be supplied by the Medium Voltage grid. In many cases, powering from the medium voltage grid is needed even for smaller demands, depending on the low voltage grid and its charging capability.
A Medium Voltage Substation consists of:
- Medium Voltage Fields: The instruments needed for link and protection. The substation’s arrivals and departures of cables are installed inside metallic cabinets with appropriate layouts called Medium Voltage Fields.
- Medium Voltage Power Transformer: The power transformer is the layout that converts the grid’s 20kV medium voltage to 400V low voltage , in order to supply the consumer. Depending on the cooling type it can be categorized to Dry cooled and Oil cooled transformers.
- Main Low Voltage Electrical Panel: Like the medium voltage fields, the main low voltage electrical panel has the necessary electric switching & circuit breaker layouts and also hosts the departures and arrivals of the low voltage cables.
The equipment described above can be installed either indoors or outdoors, inside an outdoor substation kiosk.
Anysma can take on every task needed for a Medium Voltage Substation:
- Study and plan of the MV Substation according the Power supply provider (ΔΕΔΔΗΕ & ΔΕΗ) standards, the regulations and standards of safety and the installation requirements.
- Installation of the MV Substation from our certified engineers using products of the main European manufacturers .
- Maintenance of the MV Substation. The services that we provide include:
- Visual and acoustic check
- Detailed Cleaning of the area, fields, insulators, terminals and cables.
- Insulation check using our specialized instrument for measuring insulation resistance (Megger)
- Check of the protection circuit operation
- Oil sampling (for oil cooling transformers) and testing at a certified laboratory
- Silica gel replacement
- Checking of the tightness of screws at copper bars in Medium Voltage Fields and Low Voltage Electrical Panels
- Lubrication of mechanical parts of the Medium Voltage Field
