Experiment-Based Study of Heat Dissipation from the Power Cable in a Casing Pipe

Abstract

The paper deals with the important challenges in terms of electricity transmission by means of underground cable lines. The power cable’s performance is characterized by an ampacity that represents its maximum electric current-carrying capacity. The ampacity of power cables depends on their ability to diffuse the heat generated by the current flow into the environment. In the performed research, the analysis of the efficiency of heat dissipation from the cable is based on the measurement of temperatures at selected points in individual sections of the cable. As a consequence, the proposed test stand and applied research methodology are vital for the experimental evaluation of the analyzed thermal phenomena in the investigated underground cable lines. The research program covers an in-depth analysis based on the results related to the vital parameters of the investigated cable. The experimental methodology was used to analyze the influence of the properties of the medium surrounding the cable on its temperature, and thus on the ampacity of the cable. A novelty of this paper concerns the carrying out of the experimental laboratory research with actual measurements of the temperature distribution in specific points of the casing pipe based on the original test stand. The paper presents the novel concept of the developed stand for testing heat dissipation from the cable in a casing pipe with pipe sections filled with various media, equipped with a power supply system ensuring easy control of the power dissipated in the cable. The preliminary results of the comparative tests, in which the temperature distribution in the sections of the casing pipes was recorded, indicate that the findings are satisfactorily consistent with the assumptions related to the purpose of the research. The use of appropriate materials surrounding the cable contributes to more effective heat dissipation, and as it has been shown for the examined case in originally planned and conducted tests, it can lower the cable temperature by more than 20 °C, contributing to a significant increase in the ampacity of the cable. For example, it was recorded that for different media filling the pipes, the cable reached 30 °C with different currents flowing through cable of 60 A and 120 A, respectively.

Mathematical modeling of road heating system with underground distribution line based on nonlinear ODE model

“…As far as the authors of this paper could examine the temperature variation of power transmission and distribution cables from the [5,7] and etc., the time scales of the variation are on the order of 30 minutes to 1 hour before setting a steady state value. In addition, the considered time scales on thermal diffusion in the underground are from 5 minutes to 1 hour when considering boundary surfaces such as the ground surface and pipe wall from the [15][16][17] and etc. Although a slight difference can be observed with the thermal diffusion of power distribution cables, considering the problems in these references and the differences of the actuators for controlling the temperature, we can conclude to be comparable to the thermal diffusion in the underground distribution cables.…”

The Effect of the Vertical Layout on Underground Cable Current Carrying Capacity

“…Numerous studies in the literature investigate the changes in the current carrying capacity of cables in the case of directly buried or thermally filled materials using either flat or trefoil placement methods [2]. Previous research studies [3][4][5] have focused on examining the impact of different factors on the ampacity of cables in varying thermal conditions. These factors include cable placement near heat sources, like steam pipes, using different backfill materials for underground cables, and air temperature for free-air cables.…”

Multi-Channel Virtual Instrument for Measuring Temperature—A Case Study

“…The aim of the research related to the content of this paper was to develop, calibrate and test the properties of a multi-channel temperature measurement system dedicated to research on energy dissipation from power cables in casing pipes with various fillers running in underground ducts [2]. Comparative temperature measurements were used to assess the efficiency of heat removal from the cable to surrounding media with different thermal properties.…”

“…Comparative temperature measurements were used to assess the efficiency of heat removal from the cable to surrounding media with different thermal properties. Predicted temperatures under these conditions usually range from Electronics 2023, 12, 2188 2 of 17 10 to 70 • C. In the form of a laboratory model simulating underground power lines, a test stand was developed for the experimental assessment of temperature distribution in casing pipes filled with various media surrounding the power cable [2]. A multi-channel temperature measurement system was required to perform the assessment as intended.…”