Transformers & Grid

From power generation facilities to substations at different voltage levels, power transmission and transformation systems are responsible for high-voltage power delivery, voltage conversion, and grid interconnection. These applications place stringent requirements on the electrical strength, thermal class, partial discharge performance, mechanical strength, and long-term operating reliability of magnet wires. We provide stable and reliable solutions in wrapped conductors, enameled rectangular wires, and continuously transposed conductors for manufacturers of power transformers, reactors, converter equipment, and other high-voltage electrical apparatus.

Applications Overview

Power transmission and distribution equipment typically operates under high-voltage, high-current, and continuous-load conditions:

Medium- and high-voltage equipment must withstand power-frequency and impulse voltages, requiring strict control of partial discharge and dielectric withstand consistency.
Continuous operation makes winding temperature rise a critical factor affecting equipment service life.
Short-circuit events expose windings to severe mechanical and thermal stresses caused by high fault currents.
Humidity, salt spray, and temperature variations place demanding requirements on insulation durability.
Increasingly stringent grid-efficiency requirements demand lower additional losses.
Typical design lifetimes of 20–40 years require excellent long-term aging performance of conductor and insulation materials.

Customer Challenges

Excessive partial discharge or failed dielectric tests
Excessive winding temperature and accelerated aging
Short-circuit deformation and insulation damage
High losses in large-capacity transformers
Poor compatibility with oil-immersed systems
Batch variation affecting winding processes
Long lead times and incomplete certifications

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Key Requirements

Uniform insulation with strict control of voids and impurities
Proper thermal class selection (155/180/200/220)
Improved mechanical strength and thermal shock resistance
Higher space factor and reduced circulating-current and additional losses
Oil resistance, low gas evolution, and long-term material stability
Tight dimensional tolerances and batch-to-batch consistency
Comprehensive quality systems and stable production capacity

Yuheng Solution

Customized insulation structures

Mica tape wrapping, paper covering, fiberglass covering, enameling, and combined insulation structures

Thermal class matching

Partial discharge and dielectric optimization

Low-loss solutions

Oil compatibility verification

Process adaptation

Batch consistency

Applicable Equipment

Oil-immersed power transformers
Dry-type transformers
Distribution transformers
Reactors
Converter transformers
Traction transformers
Instrument transformers and bushings
GIS/switchgear
Energy storage power conversion equipment
Wind/solar step-up transformers

Capability Evidence

Withstand & PD Testing

Automated voltage tester verifies withstand and PD levels reel by reel.
Surface & Dimension Inspection

Vision measuring for OD tolerance and batch consistency control.
Dielectric Loss Testing

Low tanδ verified for long-term insulation reliability.
Full-Process Laboratory

Mechanical, resistance and thermal testing with full traceability

Tell Us About Your Application

Share your winding specifications and loss requirements — our engineers will confirm the transposition and insulation design and reply within one day.