An improved quasi-zero stiffness vibration isolation system utilizing dry friction damping

2020-07-01
Quasi-zero stiffness (QZS) isolators, a nonlinear vibration isolation technique, enhance the isolation performance, by lowering the natural frequencies of an isolation system while providing higher static load bearing capacity compared to similarly performing linear isolators. Despite its performance improvement, the challenge of implementing QZS isolation systems is due to their highly nonlinear stiffness characteristics as a result of cubic like behavior of stiffness elements used. Although increasing linear damping in the isolation alleviates the input dependency of the QZS isolation systems by reducing the resonance amplitudes, it results in increased transmissibility in the isolation region, which is an adverse effect. Therefore, in this study, in order to overcome this, dry friction damping is implemented on the QZS isolation system. Hysteresis loop for the new QZS dry friction element is obtained and a mathematical model is introduced. For the nonlinear isolation system, harmonic balance method is used to transform the nonlinear differential equations into a set of nonlinear algebraic equations. For single harmonic motion, analytical expressions of Fourier coefficients are obtained in terms of elliptic integrals. Numerical solution of the resulting set of nonlinear algebraic equations is obtained via Newton's method with arc-length continuation. Performance of the isolation system under periodic base excitation is studied for different base excitation levels and the stability of the periodic steady-state solutions is investigated.
NONLINEAR DYNAMICS

Suggestions

A new modal superposition method for nonlinear vibration analysis of structures using hybrid mode shapes
Ferhatoglu, Erhan; Ciğeroğlu, Ender; Özgüven, Hasan Nevzat (Elsevier BV, 2018-07-01)
In this paper, a new modal superposition method based on a hybrid mode shape concept is developed for the determination of steady state vibration response of nonlinear structures. The method is developed specifically for systems having nonlinearities where the stiffness of the system may take different limiting values. Stiffness variation of these nonlinear systems enables one to define different linear systems corresponding to each value of the limiting equivalent stiffness. Moreover, the response of the n...
A current source converter based statcom for reactive power compensation at low voltage
Biçer, Nazan; Ermiş, Muammer; Department of Electrical and Electronics Engineering (2010)
This research work is devoted to the analysis, design and development of the Current-Source Converter (CSC) based distribution-type Static Synchronous Compensator (D-STATCOM) for low-voltage applications in reactive-power control in order to achieve i) faster transient response in reactive-power control, ii) lower current harmonic distortion, iii) lower power losses and iv) minimum storage elements in comparison with conventional solutions. The developed CSC-D-STATCOM includes a low-pass input filter and a ...
An Automatically Mode-Matched MEMS Gyroscope With Wide and Tunable Bandwidth
Sonmezoglu, Soner; Alper, Said Emre; Akın, Tayfun (Institute of Electrical and Electronics Engineers (IEEE), 2014-04-01)
This paper presents the architecture and experimental verification of the automatic mode-matching system that uses the phase relationship between the residual quadrature and drive signals in a gyroscope to achieve and maintain matched resonance mode frequencies. The system also allows adjusting the system bandwidth with the aid of the proportional-integral controller parameters of the sense-mode force-feedback controller, independently from the mechanical sensor bandwidth. This paper experimentally examines...
A Generalized Scalar PWM Approach With Easy Implementation Features for Three-Phase, Three-Wire Voltage-Source Inverters
Hava, Ahmet Masum (Institute of Electrical and Electronics Engineers (IEEE), 2011-05-01)
The generalized scalar pulse width modulation (PWM) approach, which unites the conventional PWM methods and most recently developed reduced common mode voltage PWM methods under one umbrella, is established. Through a detailed example, the procedure to generate the pulse patterns of these PWM methods via the generalized scalar PWM approach is illustrated. With this approach, it becomes an easy task to program the pulse patterns of various high performance PWM methods and benefit from their performance in mo...
A novel two-step pseudo-response based adaptive harmonic balance method for dynamic analysis of nonlinear structures
Sert, Onur; Ciğeroğlu, Ender (Elsevier BV, 2019-09-01)
Harmonic balance method (HBM) is one of the most popular and powerful methods, which is used to obtain response of nonlinear vibratory systems in frequency domain. The main idea of the method is to express the response of the system in Fourier series and converting the nonlinear differential equations of motion into a set of nonlinear algebraic equations. System response can be obtained by solving this nonlinear equation set in terms of the unknown Fourier coefficients. The accuracy of the solution is great...
Citation Formats
A. Donmez, E. Ciğeroğlu, and G. O. Özgen, “An improved quasi-zero stiffness vibration isolation system utilizing dry friction damping,” NONLINEAR DYNAMICS, pp. 107–121, 2020, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46641.