Experimental Investigation of the Corona Discharge in Electrical Transmission due to AC/DC Electric Fields

Abstract

Nowadays, using of High Voltage Direct Current (HVDC) transmission to maximize the transmission efficiency, bulk power transmission, connection of renewable power source from wind farm to the grid is of prime concern for the utility. However, due to the high electric field stress from Direct Current (DC) line, the corona discharge can easily be occurred at the conductor surface leading to transmission loss. Therefore, the polarity effect of DC lines on corona inception and breakdown voltage should be investigated. In this work, the effect of DC polarity and Alternating Current (AC) field stress on corona inception voltage and corona discharge is investigated on various test objects, such as High Voltage (HV) needle, needle at ground plane, internal defect, surface discharge, underground cable without cable termination, cable termination with simulated defect and bare overhead conductor. The corona discharge is measured by partial discharge measurement device with high-frequency current transformer. Finally, the relationship between supply voltage and discharge intensity on each DC polarity and AC field stress can be successfully determined. 4 4 This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits distribution, and reproduction in any medium, provided the original work is properly cited.

Comparative Study of AC and Positive and Negative DC Visual Corona for Sphere-Plane Gaps in Atmospheric Air

“…Although there are many works analyzing dc coronas, the influence of voltage on corona development is still unclear, since both, the discharge mechanisms in non-uniform electric fields and the space charge formation processes during discharges are quite complex [19]. It is a recognized fact that in most dc applications, when increasing the amplitude of the applied voltage, negative corona occurs first, at lower voltage, as proved in the experimental work of Fuangpian et al [23]. With the same atmospheric conditions, electrode and gap geometry, the spark breakdown condition under negative dc supply occurs at higher voltage than under positive dc supply, as proved in the experimental works of Pihera et al [30] and Maglaras et al [33].…”

“…However, positive corona streamers are more energy efficient in producing ozone [38]. Discharges associated to positive corona have greater amplitude and lower repetition rate than those under negative polarity [23]. Therefore, positive corona discharges present more severity.…”

“…In the literature it is reported that in several geometries such as needle-plane [19,23] or sphere-plane [20], among others, negative corona presents lower inception voltage than positive corona. However, the breakdown voltage of positive geometries often occurs at lower voltage as proved in the works of Liu et al for needle-plane gaps [19] and Wais et al dealing with sphere-plane geometries [20].…”

Electric field and force characteristic of dust aerosol particles on the surface of high-voltage transmission line

“…It can be seen that the majority of existing studies primarily focus on the ground total field strength, [28,29] the electromagnetic environment characteristics surround-ing high-voltage AC and DC conductors without adhering particles, [30][31][32][33] and analysis of insulator electric field. [34][35][36] However, there are fewer studies on the electromagnetic environment characteristics on the surface of high-voltage DC conductors with varying degrees of particles adhering.…”