Photovoltaic Prefabricated Transformer Substation (YB-35/0.4-1250)

Integrated 35kV/0.4kV Substation for Utility-Scale Solar Power Systems

The YB-35/0.4-1250 Photovoltaic Prefabricated Substation is an all-in-one outdoor unit designed for solar energy collection and grid connection. It integrates a 35kV HV ring main unit, an oil-immersed transformer, and a low-voltage AC distribution cabinet within a weatherproof, factory-assembled enclosure.

Engineered for rapid deployment and minimal on-site work, this box-type substation is widely used in utility-scale PV farms, distributed inverter systems, and hybrid solar-storage installations. It complies with IEC 62271-202 and GB/T 17467, ensuring safe and reliable power delivery.

🔧 Key Features

Voltage Level: 35kV HV input / 400V LV output
Rated Capacity: 1250kVA (range: 630kVA – 3150kVA)
Transformer Type: Oil-immersed (ONAN) standard, dry-type optional
Structure: Three-part layout: HV switchgear, transformer, LV cabinet
Protection Grade: IP54 standard (IP65 optional)
Standards: IEC 62271-202, GB/T 17467, ISO 9001, ISO 14001
PV Application Focus: Optimized for grid-tied photovoltaic systems

🌞 Application Scenarios

AC side grid connection for solar photovoltaic farms
Transformer substation between PV inverters and transmission grid
Hybrid energy systems integrating solar + BESS
Temporary or remote renewable power supply
Suitable for rooftop, ground-mounted, and containerized PV stations

This solution has been successfully applied in projects across Asia, Europe, Africa, and South America where rapid commissioning, grid compliance, and solar-ready design are essential.

📊 Technical Specifications

Specification	Value
HV Rated Voltage	35kV ±2×2.5%
LV Output Voltage	0.4kV ±5%
Rated Capacity	1250kVA (other sizes available)
Frequency	50Hz / 60Hz
Cooling Type	ONAN (oil-immersed), ANAN (dry optional)
Short-Circuit Withstand	25kA/4s (HV), 50kA peak
Insulation Level	40.5kV / 95kV BIL
Ambient Temperature	–40°C to +45°C
Altitude	≤3000m
Enclosure Protection	IP54 / IP65
Communication Support	Optional RS485 / Modbus / IEC 61850

🧱 Modular Design Layout

High-Voltage Compartment

Load break switch or vacuum circuit breaker
Surge arresters and voltage transformer
Cable terminals and grounding
Transformer Compartment

Oil-immersed transformer with full sealing
Over-temperature alarm and pressure relief
Optional dry-type transformer for safety zones
Low-Voltage Compartment

AC circuit breakers (MCCB/ACB)
Surge protection device (SPD)
Energy meters and monitoring interface

❓ Frequently Asked Questions

• Can this substation connect directly to solar inverters?
Yes. It's designed to step up the 400V inverter output to 35kV for grid injection.

• How long does it take to install on-site?
Usually 4–8 hours. It arrives fully assembled and factory-tested.

• Is 1250kVA the only capacity available?
No. We offer 630, 800, 1600, 2500, and 3150kVA variants based on your design.

• Can it integrate with SCADA or remote monitoring?
Yes. We support Modbus, IEC 61850, and customized communication interfaces.

• What protection functions are included?
Standard surge arresters, over-temperature alarms, short-circuit trip units, and optional remote fault detection.