Design and Analysis of a Double-Layer Magnetic Circuit Structure for High-Force Density Hybrid Fuel Injector

This paper proposes the design and analysis of a double-layer magnetic circuit structure for a high-force density hybrid fuel injector. In general, fuel injector models have disadvantages such as a significant leakage flux and magnetic saturation; therefore, a finite-element method is used to detail the model design and reduce the leakage flux from the electromagnet pole to the lead pipe. This change can help improve the fuel injector performance. In addition, a permanent magnet (PM) is inserted to increase the force density. Moreover, the no-load performance and demagnetization characteristic of the injector are analyzed according to the injector's working environment. The optimized hybrid fuel injector model with a PM shows substantially improved performance compared to a conventional design.