发动机电磁气门驱动动态仿真与分析

Dynamic Simulation and Analysis of Electromagnetic Valve Actuation for Engines

用有限元法和集总参数法对一试验用电磁气门驱动(EVA)系统进行了动态仿真。在集总参数法中,根据牛顿第二定律和基尔霍夫电压定律分别建立EVA系统的动力学模型和电路模型,而把电磁力随气隙、电流的变化和电流随气隙、磁链的变化分别做成数据表。用集总参数法进行动态仿真,分析了EVA中电磁铁内涡流、励磁线圈电阻和电磁力对EVA动态工作特性的影响。两种仿真都与实验结果吻合较好,但集总参数法计算效率更高,且可仿真EVA的闭环控制过程。

Dynamic simulation of electromagnetic valve actuation （EVA） was conducted on a prototype EVA by using both finite element method （FEM） and lumped parameters method （LPM）. In the LPM model for EVA, the mechanical sub--model and the circuit sub--model were based on the Newton＇s Second Law and the Kirchhoff＇s Voltage Law, respectively. And coil current map was made as a function of the gap and the flux, and so was the electromagnetic force map as a function of the gap and the coil current. The influence of eddy current in electromagnet of EVA, resistant of coil and the electromagnetic force on EVA dynamic characteristics were analyzed with LPM. It shows that simulation with two methods of FEM and LPM both agrees with the measurements well, however, LPM is more efficient, and is able to simulate EVA with closed--loop control.