Abstract—Worldwide, most PILC MV underground cables in use are approaching the end of their design life; hence, failures are likely to increase. This paper studies the electric field and potential distributions within the PILC insulted cable containing common void-defect. The finite element model of the performance of the belted PILC MV underground cable is presented. The variation of the elect...

In order to analyze the cracking and aging reason of the silicone rubber current transformer (CT) insulation bushing used for 8 years from a 500 kV alternating current substation, characteristics including Fourier transform infrared (FTIR) spectroscopy, mechanical properties analysis, hardness, and thermo gravimetric analysis have been carried out. The FTIR results indicated that the external s...

The need for economic, reliable and effective delivery of electric power has lead to the search for new, efficient and effective methods for diagnosing the insulation of the HV equipments in the industries all over the world. One of the methods currently being investigated as a potential nondestructive diagnostic tool for condition monitoring of the oilpaper insulation of power transformers is ...

SiO2 hollow spheres and low relative permittivity insulation paper handsheets composed of these SiO2 hollow spheres with different weight percentages were successfully prepared. Low-content SiO2 hollow spheres were uniformly dispersed in the insulation paper handsheets. The relative permittivity of the immersed oil Kraft-SiO2 hollow sphere handsheets (K-SiO2) initially decreased and then increa...

A voltage transformer, as voltage signal detection equipment, plays an important role in a power system. Presently, more and more electric power systems are adopting potential transformer and capacitance voltage transformers. Transformers are often large in volume and heavyweight, their insulation design is difficult, and an iron core or multi-grade capacitance voltage division structure is gen...

Monitoring on underground power cables in a close-fitting manner using mobile robot can acquire more actual information about insulation status of cables. Focusing on a water tree detection module in the monitoring system, this paper proposes fringing electric field (FEF) method to detect probably formed water tree in the insulation layer. An arch substrate based interdigital FEF sensor is desi...

Abstract — The assessment of partial discharges (PDs) gives important information pertaining to the reliability of the high voltage power equipment. PDs occur in weaker regions like voids, cracks, and imperfections present inside the insulation. The PD is generally accepted as the predominant cause of long term degradation and failure of electrical insulation. Simulation environment is a signif...

Partial discharge (PD) behaviors of oil-paper insulation is distinctive in AC and DC combined electric fields in converter transformers from PD behaviors in pure AC or DC electric fields. The present study focuses on the PD developing processes and characteristics of oil-paper insulation systems with needle-plane defects under different AC/DC proportions. The degradation of oil-paper insulation...

The electric current is omnipresent and indispensable in our life. But there are always threatening dangers connected with it. One of them is the electric short circuit and we have to protect people and facilities from its effects. This protection is often provided by power circuit breakers or motor protective circuit breakers. These devices are able to detect the short circuit, limit the curre...

Power transformers use Kraft paper as insulation in the electrical windings present in the core, which is immersed in oil. In service, the temperature of the windings of core will go to 75C to 85C. If the transformer is over loaded, then the temperature can exceed upto 100°C causing the cellulose chains in the paper to cleave at an accelerated rate, which results in the degradation of mechanica...