摘要:
For the electric load simulator, the torque transfer system has an important influence on the stability, loading accuracy and speed-of-response.In order to understand its dynamic characteristics, the finite element model of the system and mathematical model was established, and the natural frequency and mode shape of the system were obtained by modal analysis.The relationship between the stiffness of the spring rod, the natural frequency and the system were got through changing the stiffness of the spring rod.The results show that the mode shape is mainly the torsional and oscillating mode around the Zaxis, and the largest part of the amplitude is two couplings and spring rod in the first 6 modes of the system.With the increasing of stiffness of the elastic rod, the natural frequency, bandwidth and speedof-response are improved, but it will cause mechanical resonance of system and the excess torque, which will affect the stability of system, so it is necessary to consider the system stability, speed-of-response and excess torque when designing the stiffness of the spring rod.%加载系统对电动负载模拟器的稳定性、加载精度、响应速度等特性具有重要的影响, 为了解其动态特性, 建立了系统的有限元模型和数学模型, 通过模态分析得到系统的固有频率及振型;改变系统中弹簧杆的刚度, 得到弹簧杆刚度与固有频率和系统的关系.结果表明:在系统的前6阶模态中, 其振型主要是绕Z轴的扭转和摆动振型, 且幅值最大部分主要是两个联轴器和弹簧杆;弹簧杆刚度越大, 系统固有频率越大, 系统的频宽越宽, 响应速度越快, 但会造成系统机械谐振, 多余力矩增加, 影响系统的稳定性, 设计弹簧杆刚度的时候需要综合考虑系统稳定性、响应速度和多余力矩影响.