Open and Short Circuit Fault detection in Alternators using the rectified DC output voltage

The alternator in automotive systems with built-in rectifier can be subjected to various open circuit and short circuit faults. These faults result in harmonics in the rectified output voltage from the alternator. Most of the methods for fault diagnosis in AC machines and its power electronics require measurements using expensive sensors for current, temperature, torque etc., other methods have high computational requirements and therefore are not suitable for real time applications. The paper discusses an approach to detect the electrical faults by identifying the fault harmonics in the rectified output voltage of the alternator. In the paper, the effectiveness of this technique is demonstrated in fault detection and its severity in both simulation and practical measurements.