Flywheel energy storage technology, as an electromechanical energy conversion system utilizing high-speed rotating flywheels, exhibits significant technical advantages including high energy density, excellent efficiency, and unrestricted charge-discharge cycles, demonstrating considerable application value in renewable energy generation, aerospace, and intelligent transportation fields. As the core energy conversion component of flywheel energy storage systems, the performance of electric machines directly determines the overall system efficiency. With the continuous expansion of application scenarios, the development of high-power-density, compact electric machines has become a key research focus in this domain. This study proposes an innovative loaf-type permanent magnet topology. By optimizing the geometric configuration of permanent magnets, this structure achieves precise matching of air-gap magnetic field distribution, thereby significantly enhancing air-gap flux density and system efficiency. A mathematical model of this structure was established, and its electromagnetic performance and loss characteristics were systematically investigated through comparative analysis with segment permanent magnet structures. The findings provide valuable theoretical guidance for the optimal design of high-power-density flywheel energy storage motors.