Error comparsion and analysis of three interpolation methods for data synchronization of electronic transformer

In power system, the data synchronization of electronic transformer is the precondition and guarantee for protection´s correct operation. In this paper, the origin of electronic transformer data asynchronization is introduced first, and the common interpolation methods to solve the problem are given. Considering the most general form of the sampled signal, the interpolation error expressions of linear, quadratic and cubic spline interpolation methods are deduced and the influencing factors are discussed. Besides, the changing relationships between interpolation errors of the three methods and the influencing factors are calculated by simulation, and the interpolation accuracy of the three methods are compared and analyzed. The research results provide theoretical references for selection of interpolation methods to achieve electronic transformer data synchronization.