High Voltage Transformer Winding Deformation Detection Technical Specifications

JZP Transformer Solutions​

1. Introduction​

Winding deformation in high-Voltage Transformers is a critical safety concern, often caused by mechanical stress, thermal cycling, or short-circuit impacts. As a leader in transformer manufacturing, JZP​ adheres to the DL/T 1093-2018 Standard for Reactance Method in Winding Deformation Detection​ and integrates advanced technologies to ensure compliance and reliability. This document outlines JZP’s technical specifications for winding deformation detection, covering methodologies, equipment requirements, and operational procedures.

2. Scope​

This specification applies to:

Voltage range: 35 kV and above.

Transformer types: Three-phase and single-phase Power Transformers with concentric winding configurations.

Detection scenarios: Factory acceptance, post-transportation inspections, and post-short-circuit event assessments .

3. Key Detection Methods​

3.1 Reactance Method (DL/T 1093-2018 Compliance)​

Principle: Measures changes in winding reactance (impedance) under AC voltage to detect mechanical distortions.

Key parameters:

Frequency range: 10 Hz – 1 MHz.

Accuracy: ±0.5% for impedance values.

Test voltage: ≤2 kV (AC).

Advantages: High sensitivity to minor deformations (e.g., 0.1% impedance deviation indicates potential issues) .

3.2 Frequency Response Analysis (FRA)​

Methodology: Sweeps frequencies from 10 Hz to 20 MHz to capture winding resonance characteristics.

JZP’s enhancements:

High-resolution sampling: 50,000 data points for precise waveform analysis.

Anti-interference design: Optical isolation and shielding to mitigate electromagnetic noise .

Output: Comparative analysis of historical vs. current frequency spectra to identify shifts in resonance peaks (e.g., >3 dB variation triggers alerts).

4. Technical Requirements​
5. Testing Procedure​

   5.1 Pre-Test Preparation​

    

   Equipment check: Verify sensor calibration (e.g., Rogowski coils for high-frequency signals).

    

   Transformer state: Ensure the transformer is de-energized and grounded.

    

   5.2 Test Execution​

    

   Wiring configuration:

    

   Primary winding: Apply test signal (e.g., voltage transient from circuit breaker opening).

    

   Secondary winding: Connect sensors to measure induced signals .

    

   Parameter settings:

    

   Frequency scan steps: Logarithmic distribution for comprehensive coverage.

    

   Trigger thresholds: Auto-adjust based on transformer capacity (e.g., 110 kV transformers require 100× sensitivity).

    

   Data acquisition:

    

   Capture 200+ samples per frequency point.

    

   Real-time display of impedance magnitude/phase angle.

    

   5.3 Post-Test Analysis​

    

   Automated diagnostics:

    

   Compare against factory baseline (e.g., impedance deviation >2% indicates deformation).

    

   3D mapping of winding stress distribution.

    

   Reporting: Generate compliance reports with graphs and actionable recommendations.

    

   6. Case Study: Wind Farm Transformer​

    

   Scenario: A 33 kV wind farm transformer exhibited 15% impedance deviation post-storm.

    

   JZP’s solution:

    

   Conducted FRA testing, revealing a 4 kHz resonance peak shift.

    

   Identified partial winding displacement via 3D thermal imaging.

    

   Recommending rewinding, preventing a potential catastrophic failure.

    

   7. Compliance & Certification​

    

   International standards: IEC 60076-18, IEEE C57.152.

    

   Certifications: CE, UL, ISO 9001.

    

   Third-party validation: Annual audits by TÜV Rheinland.

    

   8. Conclusion​

    

   JZP’s winding deformation detection system combines precision measurement, AI-driven analytics, and full compliance​ with DL/T 1093-2018. By integrating cutting-edge technologies like high-frequency FRA and automated reporting, we ensure transformers operate safely and efficiently across global projects.