Investigating the inception mechanism of pulsed x-ray triggered partial discharges by time resolved measurements

Numerical modeling of partial discharges in a solid dielectric-bounded cavity: A review

“…Its value of 1.49 kV, corresponding to a mean field of 7.97 kV/mm in the cavity, approximately equals to the value of PDEV, but is obviously lower than the PDIV and the voltage obtained by Equation (1), as shown in Figure 1. The higher value of PDIV may be attributed to the effect of discharge time lag [27].…”

X-ray triggered PD measurements in small sized spherical voids at the detection limit

“…The time resolved signal is obtained electrically and confirmed by an optical PD signal. The shape of the time resolved signal is qualitatively equal to the signal recorded for larger voids [10].…”

“…Also the circuit has to be adjusted to the time resolved measurements: In order to achieve high bandwidth, a low stray inductance and capacitance is necessary. This is achieved by designing the ground and highvoltage electrode in a way that they can be used directly as coupling capacitor with Ck=61pF [10]. The PD current transformed into a voltage signal with Rm=50Ω is transmitted by a 50Ω transmission line.…”

“…The PD current transformed into a voltage signal with Rm=50Ω is transmitted by a 50Ω transmission line. The optical signal is detected by a PMT module (Hamamatsu H10721-110) with built-in power supply and spectral response from 230nm to 700nm [10]. Alternatively, the electrical signal can be measured phaseresolved and can be presented in the standard diagrams [3], where charge magnitude is shown as a function of the phase of the applied voltage.…”

“…Pulses are applied at maximum AC voltage but due to their duration of only some nanoseconds they do not disturb the phase resolved PD pattern of the void [9]. In order to show that the Pulsed X-ray Induced Partial Discharge (PXIPD) technique leads to the same PD mechanism than naturally incepted discharges, time-resolved current and light emission measurements were made which showed that naturally and Xray triggered pulses have identical shapes [10]. In this paper we address the question of the minimal void size which can be detected with PXIPD.…”