Product Overview

The HET 30kVA exciter transformer is designed for precision testing across a wide frequency range (20-300Hz), delivering dual voltage outputs (1kV/0.5kV). With ONAN cooling and A-grade insulation, it supports continuous 60-minute operation at full rated capacity.

Electrical Specifications

Thermal Performance

• Continuous operation: 60 minutes at 100% load

• Winding temperature rise: ≤65K

• Oil temperature rise: ≤55K

• Cooling method: ONAN (Oil Natural Air Natural)

• Insulation class: A-grade (25# transformer oil)

Protection Systems

1. Overvoltage Protection

• Piezoresistors on all HV outputs

• Zinc oxide arresters (IEC 60099-4 compliant)

• Ground-connected via 10kA surge arresters

2. Corona & Insulation Control

• 1kV corona-free HV bushings

• Electrostatic shield layer between windings

• Isovolumetric capacitance cores

Mechanical Design

Enclosure Features

• Steel housing with epoxy coating

• Wheel-mounted (4× industrial casters)

• Shell-type oil tank with conservator

Terminal Configuration

• LV terminals: Porcelain bushings

• HV terminals: Fiberglass-reinforced bushings

• Corona rings on all HV bushings

Winding Technology

• Cylinder-type winding with balanced capacitance

• Electrostatic compensation shields

• Inter-turn insulation (1mm Nomex® layers)

• Compound insulation tube skeleton

Installation & Maintenance

Commissioning Requirements

• Minimum 800mm clearance from grounded surfaces

• Oil dielectric strength ≥40kV before use

• Initial insulation resistance ≥5000MΩ

Service Schedule

• Monthly: Visual inspection of bushings

• Quarterly: Oil testing (BDV, moisture)

• Annual: Winding resistance measurement

Typical Applications

• Variable frequency resonance testing

• Power cable withstand testing

• Rotating machine insulation diagnostics

• Transformer factory acceptance tests