A modified Clarke´s transform and fuzzy systems applied to differential protection of power transformers

The power transformer is an electrical equipment that needs continuous monitoring and fast protection as it is very expensive and an essential element for a power system. The most common protection technique used is the percentage differential logic, which provides discrimination between an internal fault and different operating conditions. Unfortunately, there are some operating conditions of power transformers that can affect the protection behavior. This paper proposes the development of a new algorithm to improve the differential protection performance by using fuzzy logic and Clarke´s transform. An Electrical Power System was modeled using ATP (Alternative Transients Program) software to obtain the conditions needed to test the algorithm developed. The results obtained showing the advantages of the new method.