What Are You Looking For?
A prefabricated substation (also called a "box-type substation") integrates high-voltage switchgear, transformers, and low-voltage distribution equipment in a compact enclosure. It offers several advantages such as a compact structure, easy installation, reliable performance, and aesthetic design. These substations are factory-assembled and pre-tested, ensuring rapid installation on-site and shorter construction timelines. They are widely used in urban distribution networks, commercial centers, residential areas, and industrial parks to provide safe and reliable power.
1.Lightweight and Easy Maintenance: Prefabricated substations are lightweight and convenient for installation and maintenance, making them suitable for various environments such as industrial plants, urban distribution grids, parks, and residential areas.
2.Integrated Units: These substations consist of multiple electrical units like multi-circuit high-voltage switchgear, armored busbars, integrated automation systems, communication and remote-control equipment, metering, capacitor compensation, and DC power supply systems. These units are housed in a moisture-proof, rust-proof, dust-proof, rodent-proof, fireproof, theft-proof, heat-insulated, fully enclosed, and movable steel structure.
4.Advanced Technology:
The enclosure is usually made from aluminum-zinc-plated steel with a fire-resistant insulation layer inside, ensuring durability and corrosion resistance for up to 20 years.
Internal equipment includes fully enclosed high-voltage switchgear (e.g., XGN type), dry-type transformers, vacuum switches, and spring-operated mechanisms, ensuring zero exposure of live parts and a high level of safety.
The secondary system uses a microcomputer-based integrated automation system, enabling unmanned operation.
5.High Degree of Automation:
These substations are designed for full intelligent control with a protection system using microcomputer-based automation. The system supports remote monitoring of operation parameters, temperature, humidity, and even smoke detection for enhanced safety.
With a decentralized installation of equipment, they can support "Four Remote" functions—remote measurement, remote signaling, remote control, and remote adjustment.
6.Factory Prefabrication:
All equipment is pre-assembled and tested in the factory, allowing rapid installation on-site. Construction time from installation to commissioning is typically 5–8 days, significantly reducing project timelines.
7.Flexible Configuration:
Each compartment of the substation is an independent system, allowing flexibility in design and configuration according to specific operational requirements.
8.Cost-Effective:
Prefabricated substations can reduce overall investment costs by 40%–50% compared to traditional substations, especially with the use of oil-free equipment, which minimizes leakage and reduces maintenance efforts.
9.Small Footprint:
The footprint of prefabricated substations is about 1/10th of traditional substations, making them ideal for urban environments where space is limited.
10.Aesthetic Design:
With a modern, attractive appearance and customizable exterior colors, prefabricated substations can blend easily with their surroundings, making them suitable for residential complexes, stations, parks, and other urban settings.
1.Assembled Type:
This type houses high- and low-voltage equipment in metal enclosures with operating corridors. It is bulkier and less commonly used today.
2.Combined Device Type:
Here, the high- and low-voltage control and protection equipment are directly installed within the enclosure. This design minimizes maintenance, eliminates operating corridors, and is more compact. Also known as "European-style" or standard type substations.
3.Integrated Type:
In this design, the transformer and high- and low-voltage equipment are integrated into one oil tank, reducing the size further. This design is called "American-style" or compact-type substations.
1.European-Style Substations:
They are typically arranged in an “H” or “T” shape with three separate compartments for high-voltage, transformer, and low-voltage systems.
The high-voltage compartment includes load switches, ring main units, and fuses, with protective mechanisms like spring-operated switches and electrical isolation features to prevent single-phase faults.
The transformer can be oil-immersed or dry-type, with natural or forced ventilation.
The low-voltage compartment includes metering and reactive power compensation equipment.
2.American-Style Substations:
These have high-voltage switches and transformers integrated within the same oil tank, reducing the overall size.
Protection is provided through backup fuses and bay-o-net fuse for high-voltage systems.
The hv cable is connected to HV bushing with good insulation performance, and the bushing is connected to the elbow connector to seal the live parts.
1.Placement:
Substations should be placed on raised platforms to avoid flooding during rain. Ensure enough space for cable entries and exits on both the high- and low-voltage sides.
2.Grounding:
The substation uses a shared grounding network, typically created by driving grounding rods at the four corners and connecting them to form an integrated network.
3.Cooling:
Natural air circulation is typically used for cooling. Ensure that no debris blocks the ventilation around the transformer compartment.
4.Low-Voltage Circuit Breakers:
In the event of a trip, identify the cause before re-energizing to prevent accidents.
5.High-Voltage Surge Arresters:
Surge arresters should be installed for overvoltage protection, and their installation must allow for easy testing and replacement.
6.Maintenance:
Regular inspections should be conducted on high-voltage components, transformers, and surge arresters to detect and address any defects promptly.
For substations that have been out of service for over three months, comprehensive preventive tests should be performed before re-commissioning.
7.Fusing:
When replacing high-voltage fuses without breaking capability, ensure the transformer is de-energized, and follow proper mechanical interlock procedures.
8.Safety:
All cable entry and exit points should be sealed to prevent animals from entering the substation and causing accidents.
High-voltage danger signs and equipment nameplates must be clearly displayed for safety.
Through proper installation, maintenance, and operation, prefabricated substations ensure safe, efficient, and reliable power supply in urban and industrial environments.
