Thermal Impacts of Voltage Unbalance on Three-Phase Induction Motors

Three-phase induction motors are foundational to industrial applications, widely favored for their reliability and efficiency. However, their performance and lifespan can be severely impacted by supply voltage unbalance—a common occurrence that can be exacerbated by cyberattacks targeting control systems. This paper investigates the thermal effects of unbalanced voltages on induction motors, specifically analyzing temperature variations across key components such as windings, the rotor core, stator iron, and motor casing. Through simulations conducted in MATLAB Simulink, we model the impact of varying degrees of voltage unbalance (5%, 10%, and 20% Voltage Unbalance Factors) on motor temperature profiles. The results indicate that even minor unbalances significantly elevate temperatures, accelerating insulation breakdown and reducing operational life. Our findings highlight the critical need for advanced monitoring and mitigation strategies to counteract the thermal and mechanical stresses induced by voltage unbalances, thereby extending motor durability in industrial settings.