Development of a novel electro-mechanical brake motor thermal management system for nonuniform heating under extreme thermal conditions

Abstract

A challenge currently faced by automotive brake systems industry is the development of electromechanical brakes that need to overcome the impact of frictional heat on the motor performance. However, previous studies that examined motor cooling performance have been conducted in surrounding air temperatures below 80°C while considering uniform coil heat generation. These assumptions are not valid for EMB systems. This study conducted experiments that considered extreme surrounding temperature conditions and nonuniform coil heat generation. Based on the results of these experiments, a hybrid cooling system that can withstand extreme thermal conditions is proposed through simulation. The Hybrid cooling method that uses heat sinks, insulation, and phase change materials is the most effective with a reduction in the maximum coil temperature of 23 K. Moreover, Hybrid cooling attained maximum temperature of 137.1°C even in the most extreme 1-phase motor control strategy, which is 22.8 K lower than the Baseline. When tested for pad friction coefficient ranges from 0.3 to 0.5, the system operated below the target temperature reaching up to 139.9°C under the most extreme 0.31 conditions. This study shows that effective thermal management of electromechanical brake systems that ensures system durability and reliability of driver safety is achievable.