<p>The power loop layout design of SiC motor controllers plays a crucial role in enhancing overall controller performance. In order to investigate the more complex multiphysics coupling effects introduced by high-temperature, high-voltage, and high-switching-frequency SiC power modules, it is essential to explore high-performance power loop layouts. However, existing motor controllers lack effective analysis methods for evaluating the electrical performance of different power loop configurations, which has become a key technical bottleneck restricting the development of SiC motor controllers. This paper adopts circuit equivalence and parameter separation methods to analyze the influence of different components and busbar angles on the stray inductance of the motor controller. Based on annular film capacitors, three types of power loop layouts with varying power module angles are proposed. A multiphysics simulation system for the controller power loop is constructed using finite element and boundary element methods. The effectiveness and feasibility of the simulation system are validated through comparison with experimental results using a parallel layout. The simulation analyzes the performance of the three annular power loop layouts and compares the electrical characteristics of different physical fields under various module angle configurations. The 90° layout is identified as the optimal design, achieving an 11.5% reduction in total stray inductance and a 7.1% reduction in thermal resistance. This study provides a novel design approach and practical reference for the integrated power loop layout of SiC motor controllers used in high-temperature, high-voltage, and high-switching-frequency applications for new energy vehicles.</p>