Human Simulated Intelligent Control Of Magnetically Controllable Stiffness Damping And Inertia Torsional Vibration Of Powertrain System

The powertrain system,as the output and delivery link of power,is an important excitated vibration source and noise of ships,construction machinery,special vehicles,tanks and submarines,which has significant impact on the safety and ride comfort.With the development of high power density for power plants,the requirement for torsional vibration control of powertrain system has become urgent.The powertrain system has multi-order modes,and the main harmonic order of each mode is not the same,and the demand for stiffness,damping and moment of inertia are distinct under diverse operating conditions,for example,the system is desired to have large damping,small stiffness and small moment of inertia at start-up,which can suppress excessive oscillations and make the start-up rapidly.Obviously,the passive torsional vibration suppression technology cannot satisfy such requirements,and the adaptive control of damping,stiffness and moment of inertia is an effective approach to resolve the current torsional vibration issues in powertrain systems.Magnetorheological(MR)fluid is the most striking intelligent material currently.The MR torsion actuator developed based on MR technology can achieve the adaptive regulation of stiffness,damping and moment of inertia,which has the advantages of low energy consumption,rapid response speed and absence of mechanical wear,offering an approach to implement the semi-active control of torsional vibration in powertrain systems.Accordingly,the dissertation takes the automotive powertrain system as the objective,investigates the principle of variable stiffness damping and moment of inertia based on MR technology,explores the design method of torsional vibration absorber with variable stiffness damping and moment of inertia,establishes the dynamic model for torsional vibration of automotive powertrain system with variable stiffness damping and moment of inertia,researches the human simulated intelligent control(HSIC)algorithm for torsional vibration,and ultimately verifies the effectiveness of torsional vibration absorber with variable stiffness damping and moment of inertia as well as the control algorithm through simulation and test.The major contributions of the dissertation are presented below.1)A novel structure scheme of MR torsional vibration absorber with variable stiffness damping and moment of inertia is proposed,and the working principle of MR torsional vibration absorber with variable stiffness damping and moment of inertia is investigated.Firstly,the rheological properties of MR fluid and MR nonwoven foam,are tested and evaluated.Subsequently,the operating characteristics of the MR torsional vibration absorber are tested.The working characteristics for variable stiffness,variable damping and variable inertia of the MR torsional vibration absorber are tested respectively,which disclose the output characteristics of the variable stiffness element,variable damping element and variable inertia element under various operating conditions such as different currents and excitation sources,as well as the impact characteristics on the total output characteristics of the MR torsional vibration absorber.The high-precision mechanical control models for each element module of the magnetorheological torsional vibration absorber are established based on the test results.2)The dynamics model of automotive powertrain system is established,and the impact law of parameters such as torsional stiffness,torsional damping and moment of inertia on the torsional vibration output response of the system is uncovered through the theoretical analysis of torsional vibration suppression.A MR dynamic control model with variable stiffness,variable damping and variable inertia is established,and the hybrid Taguchi genetic algorithm(HTGA)is adopted to dynamically calibrate and optimize the stiffness,damping and moment of inertia of the powertrain system respectively.3)On the basis of the powertrain system control model,a human simulated intelligent control(HSIC)is proposed for the torsional vibration control,and the HSIC controller with partitioned cooperation and multimode multicontrollers is developed.Numerical experiments of semi-active control of powertrain system with MR variable stiffness and damping torsional vibration absorber(MRI-VSDTVB)are simulated under sinusoidal and random excitations.The simulation results show that the three control strategies can effectively suppress the torsional vibration of the powertrain system,in which HSIC achieves the optimal comprehensive effect.For the powertrain system with MRII-VIF,HSIC controller is also effective in optimizing the torsional vibration of the powertrain system with MR variable inertia flywheel(MRII-VIF)compared to passive system under random excitation.Imposing HSIC controller on the powertrain system with MR variable stiffness variable damping and variable inertia can significantly improve the output behavior of the system in the broadband.4)Taking advantage of d SPACE control algorithm rapid prototype technology,a general research platform for real-time control of MR semi-active powertrain system is constructed based on d SPACE,and a real-time control platform for the powertrain system with MRI-VSDTVB and the powertrain system with MRII-VIF are built respectively by replacing the system hardware framework.A series of open-loop control tests and closed-loop semi-active control tests are carried out,including(1)The open-loop control tests of MR variable damping element with constant current,MR variable stiffness element with constant current,and MR variable inertia element with constant current and constant moment of inertia are carried out.The test results show that the output fluctuation of MR powertrain control system with MRI-VSDTVB tends to decrease with the increase of damping in a certain frequency range,and gradually shows a frequency shift with the increase of stiffness;the output fluctuation of MR powertrain control system with MRII-VIF tends to increase with the increase of moment of inertia in the range less than the cut-off frequency.The above test results indicate that continuous control of the output characteristics of the MR powertrain control system can be achieved by adjusting the damping,stiffness and moment of inertia continuously,which verifies that the proposed novel idea of employing variable stiffness damping and moment of inertia to implement effective control of the output characteristics of the powertrain system is feasible.(2)The semi-active real-time control tests of powertrain system with MRIVSDTVB and powertrain system with MRII-VIF are carried out.The test results show that HSIC has a significant suppression effect on the torsional vibration of powertrain system with MRI-VSDTVB in the whole test frequency scope,which is significantly better than the passive system and skyhook control system.HSIC controller is also effective in suppressing torsional vibrations of powertrain system with MRII-VIF under random excitation.The entire test results demonstrate that HSIC proposed in this dissertation can significantly improve the output characteristics of the MR semi-active powertrain system in the broadband,which lays the foundation for the subsequent tests of the continuous rotation powertrain system.