Khamlichi Abderrahim, Garnacho Fernando, Simón Pascual
Fundación para el Fomento de la Innovación Industrial, FFII-LCOE, Eric Kandel Street 1, 28906 Madrid, Spain.
Departamento de Ingeniería Eléctrica, Electrónica, Automática y Física Aplicada, ETSIDI, Universidad Politécnica de Madrid, 28006 Madrid, Spain.
Sensors (Basel). 2023 Jun 27;23(13):5955. doi: 10.3390/s23135955.
A synthetic partial discharge (PD) calibrator has been developed to qualify PD analyzers used for insulation diagnosis of HVAC and HVDC grids including cable systems, AIS, GIS, GIL, power transformers, and HVDC converters. PD analyzers that use high-frequency current transformers (HFCT) can be qualified by means of the metrological and diagnosis tests arranged in this calibrator. This synthetic PD calibrator can reproduce PD pulse trains of the same sequence as actual representative defects (cavity, surface, floating potential, corona, SF protrusion, SF jumping particles, bubbles in oil, etc.) acquired in HV equipment in service or by means of measurements made in HV laboratory test cells. The diagnostic capabilities and PD measurement errors of the PD analyzers using HFCT sensors can be determined. A new time parameter, "PD Time", associated with any arbitrary PD current pulse is introduced for calibration purposes. It is defined as the equivalent width of a rectangular PD pulse with the same charge value and amplitude as the actual PD current pulse. The synthetic PD calibrator consists of a pulse generator that operates on a current loop matched to 50 Ω impedance to avoid unwanted reflections. The injected current is measured by a reference measurement system built into the PD calibrator that uses two HFCT sensors to ensure that the current signal is the same at the input and output of the calibration cage where the HFCT of the PD analyzer is being calibrated. Signal reconstruction of the HFCT output signal to achieve the input signal is achieved by applying state variable theory using the transfer impedance of the HFCT sensor in the frequency domain.
已开发出一种合成局部放电（PD）校准器，用于对用于暖通空调（HVAC）和高压直流（HVDC）电网绝缘诊断的PD分析仪进行鉴定，这些电网包括电缆系统、空气绝缘开关设备（AIS）、气体绝缘开关设备（GIS）、气体绝缘输电线路（GIL）、电力变压器和HVDC换流器。使用高频电流互感器（HFCT）的PD分析仪可通过该校准器中安排的计量和诊断测试进行鉴定。这种合成PD校准器能够重现与实际典型缺陷（如运行中的高压设备中出现的空腔、表面、浮动电位、电晕、SF突出物、SF跳跃颗粒、油中气泡等）相同序列的PD脉冲序列，或者通过在高压实验室测试单元中进行的测量来重现。使用HFCT传感器的PD分析仪的诊断能力和PD测量误差可以确定。为了校准目的，引入了一个与任意PD电流脉冲相关的新时间参数“PD时间”。它被定义为与实际PD电流脉冲具有相同电荷量和幅度的矩形PD脉冲的等效宽度。合成PD校准器由一个脉冲发生器组成，该脉冲发生器在与50Ω阻抗匹配的电流环上运行，以避免不必要的反射。注入电流由内置在PD校准器中的参考测量系统测量，该系统使用两个HFCT传感器，以确保在校准笼的输入和输出处电流信号相同，PD分析仪的HFCT在校准笼中进行校准。通过在频域中使用HFCT传感器的转移阻抗应用状态变量理论，实现HFCT输出信号到输入信号的信号重构。
