动铁式电磁调速执行器动态特性影响因素分析

Analysis of Influencing Factors on Dynamic Characteristics of Moving Iron Electromagnetic Governor Actuator

为提高柴油机电磁式调速器的性能,揭示调速执行器动态特性参数的影响规律,采用数值模拟与试验相结合的方法,建立了动铁式电磁调速执行器的数值仿真模型,并通过试验验证了模型的精度,其最大误差为7%。通过数值模拟研究分析了电磁调速执行器的动态工作特性及脉冲宽度调制(pulse width modulation,PWM)频率、弹簧预紧力、弹簧刚度、负载大小、线圈匝数及导磁材料等参数对执行器动态特性的影响。结果表明:初始阶段适宜采用大占空比或满占空比来加快执行器的动态输出速度,以较小的占空比来维持满行程的输出以提高执行器的动态回位速度;提升执行器的位移力的水平特性有助于提高执行器行程输出的线性度;此外,发现PWM频率、弹簧预紧力、弹簧刚度、负载大小、线圈匝数及导磁材料等参数对执行器动态特性均具有重要影响。

In order to improve the performance of diesel electromagnetic governor and reveal the influence rules of dynamic characteristic parameters for electromagnetic governor,the method of combining numerical simulation with experiment was applied.The numerical simulation model of moving iron electromagnetic governor was established,and the accuracy of model was verified with the maximum error 7%by experiment.Dynamic operating characteristics and the influence of parameters such as pulse width modulation(PWM)frequency,spring preload,spring stiffness,load,coil turns and magnetic materials of magnetic circuit on the dynamic characteristics of actuator were analyzed by numerical simulation.The results show that high duty ratio or full duty ratio is suitable to be applied to speed up the dynamic output speed of actuator in the initial stage,while low duty ratio is suitable to be used to maintain the output of full stroke for improving the dynamic return speed of actuator.Then enhancing the horizontal characteristic of displacement-force helps to improve the linearity of stroke output for actuator.Besides,it is found that parameters such as PWM frequency,spring preload,spring stiffness,load,coil turns and magnetic materials of magnetic circuit have an important impact on the dynamic characteristics of actuator.