Lightning Impulse Corona Characteristic of 1000-kV UHV Transmission Lines and Its Influences on Lightning Overvoltage Analysis Results

Attenuation and deformation characteristics of lightning impulse corona traveling along bundled transmission lines

“…Based on the experimental results, it is summarized in our previous paper [17] that the negative lightning impulse corona Q-V curve fits the power function well after the voltage exceeds the corona inception value:…”

“…It first appeared in the test results of paper [18] that the knee points of the same conductors under different amplitudes of positive lightning impulse are different, and the corona inception delay time is proposed to indicate this phenomenon in our previous paper [17]. The inception voltage, knee point voltages and corona onset delay times on ten types of bundle conductors measured under different magnitudes of positive lightning impulse are presented in Table 1.…”

“…The experimental setup of the UHV corona cage is previously introduced in our paper [17], as shown in Fig. 5 mesh cage is composed of a 25 m long measuring section in the center, and two 5 m long shielding sections at each end.…”

“…C cond is the capacitance between the bundled conductors to the ground considering impulse corona effects. k is the power coefficient of the empirical formula, which is derived from the regression analysis to the curves of different bundled conductors, the value of which can be referred in [17].…”

Corona lightning overvoltage analysis for a 500 kV hybrid line

“…Among the effects produced by overvoltage surges that have been attracting the attention of researchers on the OHTLs is the corona phenomenon or corona discharge [18–23]. When an overvoltage transient occurs on a transmission line due to a lightning strike or switching operation, it propagates in both directions and can become harmful to line and station equipment [20].…”