Noise mitigation and noise evaluation diagnostics of solar material partial discharge test equipment in a NIST audited emissions and immunity compliant testing chamber

Partial Discharge is one of a number of tests defined in IEC61730-2, which specifies properties of photovoltaic modules and components. 3M has used commercially available test equipment from Phenix Technologies to complete a detailed evaluation of noise mitigation techniques for effectively implementing the IEC test standard 60664-1 for Partial Discharge Testing. The PD2U partial discharge detector was designed for quality assurance and quality control tests of high, medium and low voltage insulation in a test laboratory environment. This instrument can be adapted to measure partial discharge inception and extinction voltages per IEC Standard IEC 60664-1 by use of various preamplifier and couplers. The standard set configuration of the PD2U consists of a coupling unit CIL4L, a preamplifier RPA1 and the instrument. The acquisition unit controls the power supply and the Preamplifier unit (RPA1) through a standard coaxial cable which also transmits the partial discharge signal. Compliance with IEC 60664-1 requires background noise levels to remain under 1 pC. Using noise mitigation and noise evaluation diagnostics in a NAVLP certified IEC emissions and immunity compliant testing chamber resulted in continually sustained background noise levels of less than a few hundred fC. The noise mitigation hardware we have evaluated includes noise filters, designated power synthesizers and isolation transformers, and NAVLP certified and FCC approved shielded enclosures. Given our evaluations and insights gained as a result of this study, our 3M laboratory has been able to routinely carry out partial discharge testing for the purpose of advanced materials research and development.