Fault Detection and Diagnosis in Duals Converters Applied in DC Drives

Although nowadays ac drives are more frequently used, dc drives continue being used, mainly in industrial plants, as in Açominas. Normally, duals converters compose these drives, were faults related with them are important in relation with available time of equipments. Besides, speed sensors, as taco generator and pulse generator, are important factor to become these systems weaker. Then, in this work presents a fault diagnostic and detection system to commutation, short circuit and circuit open fault. Speed sensors faults are detected too, with automatic feedback reconfiguration. The fault diagnostic and detection system is based in fuzzy theory to generate inputs to a neural network responsible for fault classification, and states observer to detect sensor speed fault. All results were obtained from digital simulations. This system showed simple and efficient in the detection of the proposed fault. Other advantage is the control system reconfiguration based in states observers. It is permit the drive system operation when a speed sensor faults. So, the result encourage the practical implementation of this proposed detection fault system in a dc drives.