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Introduction
Published in Anjan K. Deb, Power Line Ampacity System, 2017
Aluminum Conductor Steel Reinforced (ACSR) is the most widely used type of current-carrying conductor. All Aluminum Conductors (AAC) are used in coastal regions for high corrosion resistance and also for applications requiring lower resistance, where the high strength of a steel core is not required. More recently, All Aluminum Alloy conductors have been used for their light weight and high strength-to-weight ratio, which enables longer spans with less sag. Other hybrid conductors having various proportions of aluminum, aluminum alloy, and steel wires are also used for special applications. The popular type of hybrid conductors are Aluminum Conductor Alloy Reinforced (ACAR) and Aluminum Alloy Conductor Steel Reinforced (AACSR). Some examples of commonly used powerline conductors according to various standards are given in Appendix A (Thrash, 1999; Koch, 1999; Hitachi, 1999).
Short-Circuit Calculations according to ANSI Standards
Published in J.C. Das, Power System Analysis, 2017
Overhead line conductors. Calculations of short-circuit withstand ratings for overhead line conductors must also receive similar considerations as cables, i.e., these should be sized not only for load current and voltage drop consideration, but also from short-circuit considerations. For ACSR (aluminum conductor steel reinforced) conductors, a temperature of 100°C (60°C rise over 40°C ambient) is frequently used for normal loading conditions, as the strands retain approximately 90% of rated strength after 10,000 h of operation. Under short circuit, 340°C may be selected as the maximum temperature for all aluminum conductors and 645°C for ACSR, with a sizable steel content. An expression for safe time duration based on this criterion and no heat loss during short circuit for ACSR is given in [24]:
Power Distribution Fundamentals
Published in Stephen W. Fardo, Dale R. Patrick, Electrical Power Systems Technology, 2020
Stephen W. Fardo, Dale R. Patrick
Almost all conductors are made of either copper or aluminum. Both of these metals possess the necessary flexibility, current-carrying ability, and economical cost to act as efficient and practical conductors. Copper is a better conductor; however, aluminum is 30 percent lighter in weight. Therefore, aluminum conductors are used when weight is a factor in conductor selection. One specialized overhead power line conductor is the aluminum-conductor, steel-reinforced (ACSR) type used for long-distance power transmission. This type of conductor has stranded aluminum wires.
Sequential Estimation of the Radial Temperature Variation in Overhead Power Cables
Published in Heat Transfer Engineering, 2022
Farith M. Absi Salas, Helcio R. B. Orlande, Luis A. M. C. Domingues, Carlos R. N. Barbosa
Design and analysis of overhead power cables for electric energy transmission require multidisciplinary approaches, which aim at increasing the current transport capacity (ampacity) and at reducing energy losses. Overhead power cables used in transmission lines are mainly composed of two materials, such as the quite common Aluminum Conductor Steel Reinforced (ACSR) cable. In this cable, the inner core is made of steel wires in order to provide the required mechanical resistance to reduce the number of transmission towers. Over this core, layers of aluminum wires are wound to form the conductor, which carries approximately 98% of the electric current [1]. The cross section of an ACSR cable (model TERN, with 45 aluminum and 7 steel wires) is presented in Figure 1.
Current Tolerance Capability Calculation Model of Transmission Lines and its Application in Overload Protection
Published in Electric Power Components and Systems, 2018
Jian Hu, Xiaofu Xiong, Jian Wang
At present, the most commonly used conductor in transmission lines is the aluminum conductor steel-reinforced (ACSR) cable [32], which consists of multiple layers of steel core and aluminum layers twisted together, as shown in Figure 1. When current passes through conductor, a temperature rise in the layers caused by the power loss occurs. When the cooling conditions of the entire conductor are the same, the study about heat transfer characteristics of the conductor are mainly to solve the heat conduction problem between the cross-section layers.