Optimization of Dynamic Performance of a Solenoid Actuator in a CNG Injector Based on the Effects of Key Design Parameters

A model-based study is conducted to optimize the dynamic performance of a solenoid actuator in a compressed natural gas (CNG) injector. A mechanical model, an electromagnetic model, and an optimum model using particle swarm optimization (PSO) algorithm are built to depict operation and optimize the dynamic response times of the injector solenoid actuator. Effects of the number of coil turns ( N ), spring stiffness ( k ), and gap between plunger and cylinder wall ( g ), on the dynamic characteristics of the injector solenoid actuator are investigated. Simulation results show that, when k increases from 560 to 2560 N/m, and g increases from 0.1 to 0.5 mm, the opening response time increases 35.41% and 48.03%, respectively; however, the closing response time of the injector solenoid actuator reduces 27.27% and 45.25%, respectively. When N is increased from 342 to 552, the opening response time reduces 35.48%; nevertheless, the closing response time increases considerably with a 195.45% increment. Using PSO algorithm, it is found that the optimum version of the injector solenoid actuator has improvements for both opening and closing response times, in which the opening response time reduces 11.41% when compared with the original version.