ATC improvement and losses estimation considering dynamic transmission line ratings

In the last few years, Reconstruction in electrical industry has led to optimal using of existing transmission lines capacity in order to reach to maximum economic efficiency. Improvements in communication technologies and sensors make possible real time calculation of transmission lines thermal capacity, which is called dynamic rating. On the other hand, in energy markets, system conditions and transmission capacities for future operations are the essential keys. Operators would like to know the amount of the system losses and also Available Transfer Capability (ATC) which effect on the market players´ activities. Improvement in losses estimation and ATC calculation, considering dynamic transmission lines rating, instead of static rating, is discussed in this paper. Losses estimation is performed by using repetitive calculation of lines resistance based on weather conditions. It is shown that using of dynamic rating has a very important effect in ATC calculations. A program is developed for calculation of dynamic rating in MATLAB software, but system modeling and calculation is performed by DigSILENT package. Data transfer between two software is possible through a link which is created by using DigSILENT Programming Language (DPL). IEEE 6-bus and 30-bus test systems have been used and modified as test systems.