This paper presents online components calculation techniques for stator and rotor of the induction machine. Four techniques have been developed for online components calculation; the first one starts the calculation of the negative component of stator current space vector using the Discrete Fourier Transform (DFT) in order to detect the stator fault. The second technique is dealing with the detection of rotor fault by the Recursive Fourier Transform (RFT), This technique improves the signal acquisition and enhanced detection of components near the fundamental. The third technique allows improving of the rotor fault detection by the spectrum of analytical signal. The fourth and the last technique is the frequency analysis of the instantaneous power, which allows obtaining a singular signature of faults. These techniques have shown better detection, where each fault is characterized by a singular signature and therefore they improve the detection and diagnosis of faults. Experimental results applied on an asynchronous machine 5.5 kW, approve and validate these calculation techniques
