Fault tolerant behavior of advanced control schemes of induction machine drives

Abstract

Power electronics based variable-speed drives offer energy saving solutions, providing precise control and quick response time. They are required for sensitive process control in industrial applications and other emerging technologies such as electric vehicles. This thesis examines two popular advanced control schemes of variable-speed induction machine drive applications. The two advanced control schemes, Indirect Field oriented control (IFOC) and Direct torque control (DTC), are compared by examining their implementation complexity, parameter sensitivity, dynamic responses, steady state performance and, most importantly, under power line fault scenarios. MATLAB-Simulink package is used to develop system models for both control schemes. System studies are done under normal and abnormal operating conditions. In the end, conclusions are drawn based on their behavior and comparison of performance characteristics under dynamic and AC fault (single-line to ground, phase to phase and triple-line to ground) conditions, highlighting the fault tolerant characteristics of the two drive schemes.