Induction Motor Voltage Variation and Fault Adaptation in Submarines

Induction motors are critical components in submarine systems, powering propulsion and auxiliary machinery under challenging operational conditions. These motors, however, are susceptible to faults such as voltage disturbances and mechanical anomalies that can compromise performance and operational safety. This research investigates the fault adaptation mechanisms for induction motors in submarine scenarios by integrating wavelet decomposition for fault detection and undervoltage relays for fault adaptation and mitigation. Wavelet transform analysis is employed to detect transient faults, specifically voltage disturbances occurring between 0.3 and 0.7 seconds. The system identifies fault characteristics in real-time using the high-resolution capabilities of discrete wavelet transforms, allowing precise localization and classification of anomalies. An undervoltage relay, integrated into the system, adapts to the fault condition by tripping the motor at 0.54 seconds to prevent prolonged exposure to damaging voltage dips. The study utilizes MATLAB/Simulink to model and analyze a 7.5 kW, 400 V, 1440 RPM induction motor operating under realistic submarine conditions. For fault identifications, twelve different scenarios are examined: Three phase to ground fault, three phase fault, double line to ground fault (AB-G), double line to ground fault (AC-G), double line to ground fault (BC-G), line to line fault (A-B), line to line fault (A-C), line to line (B-B) fault, single line to ground fault (A-G), single line to ground fault (B-G), single line to ground fault (C-G), and no faults. Also, for fault adaptation using under-voltage relay, two different scenarios are simulated for reference purpose: single line to ground and three phase to ground. Simulation results demonstrate the effectiveness of the wavelet-based detection in identifying faults early and the relay's timely intervention to protect the motor. These findings highlight the viability of integrating wavelet decomposition and adaptive relay mechanisms to enhance the resilience of induction motors in submarines.