280 / 2022-03-15 00:32:04

Technical features characterization of PD measuring systems operating with HVDC using an analog signals generator

Partial discharges in HVDC,PD instrument qualification,transfer impedance,Electrical noise,PD sensitivity,PD clustering,Insulation defects,PD pulse trains,PD patterns in HVDC

The IEC 60270 standard establishes different tests to check the functionalities of a PD measurement system that operates at frequencies of no more than 1 MHz, however no specific tests are defined for the PD measurements in higher frequencies. The functionalities of digital PD measuring systems widely used for conventional PD measurements according to IEC 60270 (at measuring frequencies ≤1 MHz) and for non-conventional ones according to TS IEC 62478 (at measuring frequencies >1 MHz) must be defined and verified, especially when they operate with HVDC. A set of PD pulse trains has been designed to be generated using an arbitrary waveform generator (AWG). This set of PD pulse trains are used to determine the perfPD patterns in HVDCormance of measuring instruments working in HVDC facilities: charge reading error, q_IEC versus pulse repetition frequency N, linearity error, minimum detected charge value q_min, pulse resolution time T_r, PD pulse timing error t_i, PD polarity error, … . Other quantities such as accumulated charge, q_a, PD pulse count, m, PD pulse current can also be verified using the AWG. Considering the lower and upper limit frequencies f₁ and f₂ of the measuring instrument, an intrinsic error occurs in the measurement of the charge. A new PD parameter, TPD: "Reference PD pulse time", expressed in nanoseconds, is introduced to identify the most appropriate current pulse for testing, either for measuring instruments according to IEC 60270 or for measuring instruments according to TS IEC 62478. This paper presents the results obtained when the proposed verification procedure is applied to a commercial PD measurement system.

fgarnacho@ffii.es

The IEC 60270 standard establishes different tests to check the functionalities of a PD measurement system that operates at frequencies of no more than 1 MHz, however no specific tests are defined for the PD measurements in higher frequencies. The functionalities of digital PD measuring systems widely used for conventional PD measurements according to IEC 60270 (at measuring frequencies ≤1 MHz) and for non-conventional ones according to TS IEC 62478 (at measuring frequencies >1 MHz) must be defined and verified, especially when they operate with HVDC. A set of PD pulse trains has been designed to be generated using an arbitrary waveform generator (AWG). This set of PD pulse trains are used to determine the performance of measuring instruments working in HVDC facilities: charge reading error, q_IEC versus pulse repetition frequency N, linearity error, minimum detected charge value q_min, pulse resolution time T_r, PD pulse timing error t_i, PD polarity error, … . Other quantities such as accumulated charge, q_a, PD pulse count, m, PD pulse current can also be verified using the AWG. Considering the lower and upper limit frequencies f₁ and f₂ of the measuring instrument, an intrinsic error occurs in the measurement of the charge. A new PD parameter, TPD: "Reference PD pulse time", expressed in nanoseconds, is introduced to identify the most appropriate current pulse for testing, either for measuring instruments according to IEC 60270 or for measuring instruments according to TS IEC 62478. This paper presents the results obtained when the proposed verification procedure is applied to a commercial PD measurement system.