Application of A Line Ampacity Model and Its Use in Transmission Lines Operations

Abstract

A conductor thermal model related to CIGRE and IEEE solutions was developed and compared with measurements. Two pylons of a single line were equipped with weather monitoring stations and conductor temperature sensors based on Surface Acoustic Wave (SAW) principle. Also a fiber optic distributed temperature sensing system was installed to provide additional data. Over 2.5 million data points were evaluated. Developed model deviation for more than 99 % of values proved to be ±1 • C for SAW sensor and ±3.5 • C for the fiber optic measurement. Several ampacity determination methods were described from a transmission grid operator's point of view. Their features were compared in order to show at which planning period they could be useful. A new method for dynamic line rating determination was proposed. Although it reduces maximum ampacity gain, its advantage lies in minimizing measurement systems while retaining relatively stable value and low risk of temperature limit exceeding.

Handling large power steps in real-time microgrid control via explicit power setpoints

“…Consequently, the dynamic current limit I max l decreases, forcing the actual flowing current magnitude to decrease as well. When the current magnitude goes below (1− I )I, i J decreases exponentially letting the battery to increase the power back 6 . …”

“…Then, we emulate the power step by producing 15kW with it. 6 We take I = 0.1. This 30kW power step causes a violation of β = 4% of the nominal voltage.…”

“…For the first, we rely on the fact that the operational limit of a conductor is its maximum temperature, which will be reached at different speed depending on the magnitude of the transferred current. We consider the energy balance equation of a conductor [6],…”

Identification of the Heat Equation Parameters for Estimation of a Bare Overhead Conductor’s Temperature by the Differential Evolution Algorithm

“…Several studies deal with analytical numerical methods for assessing the temperature of overhead power line conductors [1][2][3][4][5][6][7][8][9][10], where environmental conditions and heat-balance equations have been applied [11,12].…”

Notice of Removal Dynamic optimal power flow in transmission networks with high penetration of intermittent renewable energy sources

“…For a high penetration of intermittent RESs, the transmission line current also fluctuates; therefore, it is possible that the line current may exceed the transmission line capacity. In general, the transmission capacity constraints are essentially the linetemperature constraints and not the rated current constraints because the rated current of the transmission lines is determined by the temperature limit under steadystate conditions for the line current and the ambient meteorological conditions [1]- [3]. Thus, the transmission capacity constraints must be treated as line conductor temperature constraints for a high penetration of intermittent RESs.…”