The Effect of Voltage Waveform on Phase-Resolved Electroluminescence Measurements

Abstract

Space charge plays a significant role in long term electrical degradation of polymeric insulation in high voltage cables and consequently there is growing interest in the measurement of the energy dissipation of mobile and trapped charges in dielectric molecules. The dissipation process is associated with the emission of visible photons, a process known as electroluminescence (EL) and can be used, potentially, as an indicator for the initiation of electrical ageing of insulation. This paper presents the experimental work undertaken to examine EL from different ac applied voltages. Using a charge coupled device (CCD) detection system, the setup allows the determination of the light emission occurrence respect to the applied field. Phaseresolved EL measurements have been obtained using sinusoidal, triangular and square voltages.978-1-4244-2549-5/$25.00

Modelling Electroluminescence Emission in Polymeric Material Using Dimensional Analysis Method

“…Meanwhile, the uniform field configuration utilizes plane parallel electrodes and thin polymer films in the experimental setting. Many kinds of research [8,[13][14][15][16][17][18][19][20][21] opted for this configuration because it can be used for many types of samples, as the former configuration only applies to polymers that can be made with embedded electrodes [2].…”

“…Another electroluminescence study was conducted on a thin LDPE sheet subjected to a uniform field configuration under AC stresses at room temperature [14]. Three types of voltage waveforms were applied to this material; sinusoidal AC, periodic square and triangular waveforms.…”

“…Three types of voltage waveforms were applied to this material; sinusoidal AC, periodic square and triangular waveforms. The ∆EL in [14] represented the difference in intensity levels between the maximum and lowest for each waveform as shown in Figure 6. The square applied voltage has a greater EL intensity than the sinusoidal and triangular waveforms.…”

Electroluminescence as pre-breakdown phenomenon in polymers used for underground cable insulation

“…The mechanism of EL is therefore associated with the accumulation of space charge within the dielectric material. Since the existence of space charge has been widely regarded as one of the major causes for failure of solid dielectrics, it can be said that EL measurements may provide a way to investigate electrical ageing and degradation of polymer [9].…”