Product Overview
A Compact Substation Transformer, also known as a Packaged Substation or Mini Substation, is a prefabricated electrical unit that combines a distribution transformer, medium-voltage switchgear, and low-voltage distribution board into one integrated enclosure. Designed for outdoor or indoor installation, it is widely used in urban networks, industrial parks, commercial complexes, and renewable energy systems where space, safety, and rapid deployment are key considerations.
These substations are typically rated up to 36 kV on the primary side and up to 2500 kVA in transformer capacity.
General Features
- Fully enclosed, weatherproof, and tamper-proof design
- Compact and modular construction for quick installation
- Factory-assembled and pre-tested before delivery
- Suitable for both radial and ring-type network configurations
- Designed for safe public use with internal arc protection
Typical Technical Specifications
| Parameter | Specification |
|---|---|
| Transformer Type | Oil-immersed (ONAN) or Dry-type |
| Rated Capacity | 100 kVA to 2500 kVA |
| Primary Voltage | 11 kV / 22 kV / 33 kV |
| Secondary Voltage | 400 V / 230 V |
| Frequency | 50 Hz or 60 Hz |
| Cooling Type | ONAN (Oil Natural Air Natural) |
| Vector Group | Dyn11 / Yyn0 / other per requirement |
| Impedance Voltage | 4% – 6.5% (as per IEC/ANSI) |
| Insulation Class | Class A / B / F |
| Enclosure Protection | IP54 / IP55 / IP65 (outdoor applications) |
| Ambient Temperature | -25°C to +50°C |
| Altitude | ≤ 1000 m above sea level (standard) |
| Standards | IEC 60076, IEC 62271-202, ANSI, BS |
| Protection Devices | MV fuse or SF6 breaker, LV MCCB/ACB, relays |
Main Components of a Compact Substation Transformer
1. Medium Voltage Compartment (MV Side)
- Incoming MV cable termination (11/22/33 kV)
- MV switchgear (fuse-switch combination, VCB, or SF6 RMU)
- Surge arresters
- CTs and protection relays
- Earth busbar and safety interlock
2. Transformer Compartment
- Oil-immersed or dry-type transformer
- Hermetically sealed or conservator type
- Temperature indicators, pressure relief valve, breather
- HV and LV bushings with metallic partitions
- Optional: Anti-vibration pads, fire-resistant cable entry
3. Low Voltage Compartment (LV Side)
- Outgoing MCCBs, MCBs, or ACB
- Cable terminals and distribution busbars
- Energy meter, voltage/current indicators
- Protection: Overload, short-circuit, earth fault
Structure and Enclosure Options
- Material: Mild steel, galvanized steel, or stainless steel
- Surface Finish: Powder-coated or hot-dip galvanized for corrosion protection
- Ventilation: Natural ventilation louvers or forced cooling with exhaust fans
- Mounting: Skid-mounted, pad-mounted, or pole-mounted
- Access: Independent lockable doors for each compartment
- Design Compliance: Internal arc-tested design available upon request
Applications
- Residential townships and apartment buildings
- Commercial complexes and shopping malls
- Light and heavy industrial areas
- Oil & gas fields and mining operations
- Solar power generation plants
- Construction sites and mobile substations
- Rural electrification and government projects
Advantages
Space Saving – Compact layout suitable for limited areas
Plug & Play – Quick installation, minimal civil work
Pre-Tested – Fully assembled and tested before dispatch
Safety – Tamper-proof design with interlocks and protection
Customizable – Tailored for specific network configurations
Compliance – Meets IEC, ANSI, and national standards (SIRIM, BIS, etc.)
Customization Options
- Remote monitoring via SCADA or IoT sensors
- Dry-type transformer for indoor/fire-sensitive environments
- Dual LV outputs or dual voltage transformers
- Solar + battery hybrid-ready interfaces
- Special enclosure for coastal/corrosive environments
- Anti-condensation heaters and thermostats
The Compact Substation Transformer is a modern and practical solution for efficient power distribution, especially in space-constrained and fast-deployment scenarios. Its integrated design not only reduces installation time and cost but also ensures safety, reliability, and ease of maintenance. With capacities ranging from 100 kVA to 2500 kVA, and voltage levels up to 36 kV, it is an essential part of modern urban and industrial power infrastructure.