# Hitachi Energy 315 MVA 765 kV Single-Phase GSU Transformer

> 765 kV single-phase GSU family for high-voltage generation interconnection.

> SKU: VF-HE-GSU-315M-765K | Brand: ABB / Hitachi Energy | Category: Power & Energy Equipment / Transformers / High-Voltage & Transmission Power Transformers / Generator Step-Up Transformers (GSU)

**Voltformer canonical:** https://voltformer.com/product/hitachi-energy-315-mva-765-kv-gsu-transformer - markdown version: https://voltformer.com/product/hitachi-energy-315-mva-765-kv-gsu-transformer.md

## Overview

Hitachi Energy 315 MVA 765 kV Single-Phase GSU Transformer is intended for 500 kV Grid Connection Points for Large Power Plants. Configured electrical data: 315 MVA, 765/24 kV primary/secondary voltage, 50 Hz, 1-phase, vector group YNd11 and short-circuit impedance 16%. Construction: Copper (Cu-Cu); cooling: ONAF; loss class: JEC / IEC SOTA GSU. These values support preliminary engineering selection; verify insulation levels, thermal limits, short-circuit duty, installation conditions and applicable standards against the manufacturer datasheet and the site study.

- **Application:** 500 kV Grid Connection Points for Large Power Plants
- **Target industries:** Nuclear Power Plants, Combined-Cycle Gas Turbine (CCGT) Power Plants, Mega Hydroelectric Power Plants (HPP)
- **Brand:** [ABB / Hitachi Energy](https://voltformer.com/brand/abb-hitachi-energy.md) - Global leader in high-voltage power grids and critical industrial infrastructure; Hitachi Energy delivers Resibloc® glass-fibre reinforced dry-type, TrafoStar™ large power transformers and EcoDry seri
- **Category:** [Power & Energy Equipment](https://voltformer.com/catalog.md) / **Transformers** / [High-Voltage & Transmission Power Transformers](https://voltformer.com/category/power-transmission-transformers.md): 5 MVA–1000 MVA 110 kV, 154 kV, 380 kV, 500 kV and 1000 kV UHV AC/DC transmission and interconnection power transformers. / [Generator Step-Up Transformers (GSU)](https://voltformer.com/category/power-transmission-transformers/generator-step-up-transformers.md)

## Technical Specifications

| Property | Value |
|---|---|
| Rated power | 315 MVA |
| Primary / secondary voltage | 765 kV / 24 kV (OLTC/DETC - project configured) |
| Frequency / phases | 50 Hz / 1-phase - YNd11 |
| Short-circuit impedance (Uk) | 16% |
| No-load loss P0 | 69.30 kW |
| Load loss Pk | 535.5 kW |
| Calculated efficiency (power factor = 1) | 99.8084% at 100% load; 99.8712% at 50% load |
| Loss class | JEC / IEC SOTA GSU |
| Windings | Copper (Cu-Cu) - cooling: ONAF - insulation: Class A (105°C) |
| Temperature rise | 65 K - sound pressure: 70 dB(A) |
| Mass and dimensions | 320000 kg - 11200×6400×8200 mm |
| Enclosure | IP55 outdoor - wheel gauge: 2000 mm |
| LI / AC withstand | 1913 kV peak / 918 kV rms - partial discharge: 30 pC |
| Environment | -25°C / +45°C; altitude ≤ 1000 m |
| Core steel | CRGO Laser-Treated Grain-Oriented Silicon Steel (23ZDMH85 / Baosteel B23R085) |
| Bushings / terminals | 500 kV RIP Kondenser Bushing |

## Standards

- IEC 60076
- IEEE C57
- JEC

## Accessories

**Included:** Configuration-specific technical value, Configuration-specific technical value, Configuration-specific technical value
**Optional:** Configuration-specific technical value

## Official sources

- https://www.hitachienergy.com/products-and-solutions/transformers/power-transformers/generator-step-up-transformers-gsu
- https://www.hitachienergy.com/ca/en/news-and-events/blogs/2025/06/765-kv-power-the-efficient-and-high-capacity-backbone-to-advance-north-america-industrial-electrification
- https://www.hitachienergy.com/products-and-solutions/transformers

- **Source scope:** manufacturer-family
- **Last reviewed:** 2026-09-13

Manufacturer family/application source. Hitachi Energy documents a 315 MVA, 765 kV single-phase GSU test reference. The linked public reference does not disclose every LV/nameplate value, so the generator-side voltage and order-code details require project confirmation. Exact order code, guaranteed losses, dimensions, insulation level, cooling stage, winding material and project options must be confirmed with the OEM before procurement or an SLD study.

## Pricing & Logistics

- Pricing type: RFQ (On Request) - Indicative range: $3,600,000 – $4,200,000 USD
- Delivery time: 2–8 weeks (may vary depending on technical configuration, factory capacity and destination) - Warranty: 60 months
- Compliance candidates: IEC 60076, IEEE C57, JEC. Verify applicability and conformity against the exact offered model and project jurisdiction.

## RFQ

Request a formal factory quotation via Voltformer RFQ:

```json
POST https://voltformer.com/api/v1/rfq
{"companyName":"Example Energy","email":"procurement@example.com","items":[{"skuOrId":"VF-HE-GSU-315M-765K","quantity":1}]}
```

Full catalog JSON: https://voltformer.com/agent-catalog.json - OpenAPI: https://voltformer.com/openapi.json