In this paper, a new fault detection method based on signal normalization using a simple trigonometric function is presented and applied to a five phase converter for fault tolerant application under nonsinusoidal unbalanced current waveforms. Generality, simplicity, ability to localize faulty switch, multiple switch fault detection and robustness are achieved using this approach. Once theory is explained,simulation results with Matlab/Simulink and experimental waveforms are described to show the effectiveness of the proposed detection method. Experimenal results corroborate these simulation results.