Overview
IEC TS 62758:2012 - "Calibration of space charge measuring equipment based on the pulsed electro-acoustic (PEA) measurement principle" - defines a standard procedure to evaluate and calibrate PEA systems used to measure space charge distribution in dielectric materials. Published by the IEC (Technical Committee 112), this Technical Specification gives a systematic method to determine whether a PEA measurement system is performing correctly and to convert measured voltage waveforms into reliable charge- and field-distribution data.
Key topics
- Scope and purpose: a standardized calibration method to estimate PEA system performance and verify correct operation.
- PEA measurement fundamentals: description of how pulsed electro-acoustic signals are generated, detected by a piezo-electric transducer, and related to induced charge density (see Annex A for theory).
- Calibration procedure:
- Sample preparation and placement for reproducible calibration measurements.
- Data acquisition best practices including pulse-voltage tests, averaging strategies, and recording of short-circuit reference signals.
- Data processing steps such as deconvolution to recover true voltage/pressure waveforms from distorted signals and calibration of the horizontal axis (time→depth) for spatial mapping.
- Conversion of processed signals into electric field and charge density distributions and confirmation of measurement linearity.
- Validation and typical results: guidance on expected calibration outputs and example results from research groups to help users benchmark performance.
- Practical checks: tests to confirm absence of unwanted space charge accumulation during calibration and assessment of measurement resolution.
Applications
- Quality assurance and performance verification of laboratory PEA measurement systems used in research and industry.
- Characterization and R&D of solid dielectric materials (insulating polymers, cables, transformers) where space charge affects long‑term reliability.
- Equipment manufacturers and test laboratories establishing traceable procedures to validate PEA instruments and signal‑processing chains.
- Material scientists and electrical engineers needing reproducible methods to compare space charge measurements across systems and labs.
Who should use this standard
- Test laboratories and R&D groups performing space charge measurements.
- Manufacturers of PEA systems and piezoelectric transducers.
- Standards committees, material qualification teams, and quality control engineers in electrical insulation industries.
Related information
- Prepared by IEC TC 112 (Evaluation and qualification of electrical insulating materials and systems).
- Annex A provides the theoretical basis of the PEA method; the document contains practical figures and test examples to aid implementation.
Keywords: IEC TS 62758:2012, PEA, pulsed electro-acoustic, space charge measurement, calibration, deconvolution, piezo-electric transducer, dielectric materials.