Developing More Accurate Load Flow Studies for Extreme Winter Peaks

Load flow studies are essential for planning and operating electric power systems. However, the accuracy of these studies can be affected by a number of factors, including the ambient conductor temperature. During extreme winter peaks, the ambient conductor temperature can drop significantly below 25°C, the default value used in many load flow software programs. This can lead to inaccurate results, particularly regarding voltage drop. This paper presents a case study investigating the accuracy of load flow studies during extreme winter peaks modeling various ambient conductor temperatures. The case study uses real-time meter demand and voltage data to compare actual recorded meter voltages to WindMil calculated voltages. The results of the case study show that using an ambient conductor temperature of 25°C during extreme winter peaks can lead to the model-calculated voltage drop being higher than the actual. However, using a lower ambient conductor temperature can significantly improve the accuracy of the load flow results thus potentially reducing the necessary capital expenditure from recommended system improvement projects.