Calculation method of corona loss in EHV/UHV system based on distributed parameter characteristic

Abstract

For the calculation of corona loss of extra-/ultra-high voltage (EHV/UHV) transmission lines, especially the estimation of realtime corona loss, there exists no accurate method. In this paper, a calculation method of corona loss in the EHV/UHV system based on a distributed parameter characteristic is proposed. Based on the π -shaped equivalent circuit of the long-line distributed parameter characteristic, and considering the voltage distribution along the line, a formula for calculating the corona loss under a variety of weather and annual average conditions is derived and the power equation for the corona loss of EHV/UHV system is established by the method. The example results show that the method is quite accurate. The calculation method of this paper can consider different weather conditions of the line sections to calculate the corona loss. It is more in line with the actual weather conditions on the surface of the EHV/UHV transmission lines. And the method can analyze the corona loss and its proportion to the total loss of the system under the annual average and different weather conditions. It is of great significance to the design and operation of an EHV/UHV system.

Determination Method of Cascaded Number for Lumped Parameter Models Oriented to Transmission Lines

“…Even though real-time digital simulation technology is widely used [5], physical simulation technology still holds an important position because it can intuitively reflect changes in electricity, especially under high voltage conditions. Generally, π-type and T-type circuits, or occasionally Г-type circuits are applied to physically simulate the transmission line [6][7][8][9]. These three lumped parameter models (LPMs) have high analog accuracy in systems with low frequency and short lines.…”

A new method to calculate corona losses for active conductors considering real transmission line unbalance

“…The occurrence and intensity of corona discharges, and hence their losses, is affected by the following factors: The electric field gradient on the conductor surface [16,17], the conductor surface condition [6,18], weather conditions [19][20][21], the relative air density [22,23], the effect of water on the conductor surface [20,22], the average operating voltage of the line [19,24,25], the size of phase conductors [18,26], bundled conductor lines [5,12,16,17], the existence or not of shield conductors [27], the sag value of the phase and shield conductors [28], the line unbalance and the type of structure.…”

“…In reference of the first issue, there are numerous research that analyse corona losses taking into account different approaches and different weather conditions; fog [42], frost [43,44], rain [22,45], ice [15], snow [22,46], and sand [5], to give some examples reported in literature.…”

“…Peek's formula has been used by several authors for the analysis of corona losses [30][31][32]. It has also been used as a basis for the development of new calculation methods [22,33,34].…”