Study on Triangular Excitations for Accelerated SFRA of Power Transformers

The Sweep frequency response analysis, a noninvasive condition monitoring technique, is widely used as a diagnostic tool to assess the mechanical integrity of power transformers. Industrial frequency response analysers utilize a variable frequency sinusoidal signal to determine the frequency response of power transformers at present. This work investigates the use of triangular waveforms to determine the frequency response of power transformers with reduced measurement time. Initially, the practicality of using triangular waveforms of different shapes are discussed using harmonic analysis. The simulation study on the lumped parameter circuit model of a power transformer shows the feasibility of using triangular waveforms to reduce the measurement time of sweep frequency response analysis. Usage of second and third harmonics along with the fundamental of triangular waveforms bring down the measurement time significantly in addition to the reduction of overall power analyser cost.