Auto-transformer 2*27.5kv

Changzhou Pacific Electric Power Equipment Group’s autotransformers feature compact structure, low loss, and high efficiency. With advanced design, high mechanical strength, and strong short-circuit resistance, they ensure stable and reliable operation. They have excellent voltage regulation performance, low noise, and long service life. Widely used in power transmission and distribution systems, our autotransformers save space and cost, providing safe, economical, and efficient power solutions for various projects.

Product Parameters

Rated Capacity (kV·A)	Rated Voltage (kV)		Connection Group Symbol	No-load Loss (kW)	Load Loss (kW)	No-load Current (%)
Rated Capacity (kV·A)	High Voltage	Low Voltage	Connection Group Symbol	No-load Loss (kW)	Load Loss (kW)	No-load Current (%)
6300	2×27.5	27.5	Ia0	2.9	15.4	0.55
8000				3.3	18.5	0.5
10000				3.8	21.8	0.45
12600				4.5	25.8	0.4
16000				5.4	31.5	0.4
20000				6.4	34	0.35
25000				7.5	43	0.35
32000				9	51	0.3
40000				10.5	60	0.3

Product Introduction

1. Core and Winding Configuration
The autotransformer adopts a single-frame core structure with two parallel windings for optimized performance.

2. Key Technical Features
(1) Superior Short-Circuit Withstand Capability
Autotransformers are subjected to extreme short-circuit currents. Per TB/T 2888-2010, the design must endure:

25× rated current for 2 seconds without thermal damage.
Peak transient short-circuit current for 0.25 seconds without mechanical deformation.

Enhanced Design Measures

High-strength semi-rigid self-bonding transposed conductors for all windings, which solidify during curing to form a monolithic structure, drastically improving short-circuit resistance.
Windings wound on 5mm rigid paper cylinders with external spacers to counteract radial forces during faults.
Molded insulation components provide axial support for each winding disk.
High-strength plate-type clamping frames integrate the core, yoke, and structural parts (e.g., pull plates, pressure plates, lower yoke supports), with rigorous strength validation.
Precision ampere-turn balancing ensures theoretical equilibrium, supported by tight tolerances in insulation dimensions and leveled clamping supports.
Electromagnetic-mechanical force simulations verify structural integrity, including winding stability, conductor strength, and safety margins for critical components.
Certified by the National Transformer Quality Supervision and Inspection Center through short-circuit tests, proving reliability in traction power systems with frequent faults.

(2)High Overload Tolerance
Designed for dynamic load variations, the winding hotspot temperature never exceeds 140°C under any condition.

Optimization Strategies

CFD-thermal simulations refine oil flow paths and winding temperature distribution by adjusting coil and baffle designs.
Leakage magnetic field analysis mitigates localized heating in structural parts to prevent insulation degradation.
Compliance with GB/T 1094.7-2008 (Loading Guide for Power Transformers) ensures thermal performance under cyclic short-term overloads via custom computational models.

Tested by the National Transformer Quality Supervision and Inspection Center, with all parameters surpassing technical and regulatory standards.