Arrangement Method of Vibration Dampers Considering Frequency Response Physical Characteristics and Stiffness of Conductor

In order to study the calculation method of installation distance of vibration dampers with higher precision, so as to maximize its anti-vibration performance on the conductor. The arrangement method of dampers based on the frequency response characteristics of conductors is proposed, the dynamic model of conductor considering stiffness is established. The model is solved by finite difference method, the natural frequency and vibration mode of conductor in case of Aeolian vibration are obtained, and the wavelength of conductor vibration is obtained according to its mode, so as to calculate the installation distance of vibration dampers. The calculation results of the new method are compared with those of the traditional method, which proves the advantage of the new method in calculation accuracy. The new method has a good effect on improving the calculation accuracy of the installation distance of the vibration dampers on the conductors, which is greatly influenced by its stiffness. At the same time, the frequency response of the conductor should be considered as much as possible in the calculation of the installation distance of the damper.

Dynamic analysis of electrical vibration absorbers for suspended cables

The present research proposes two vibration control techniques for attenuating vibration of laboratory-scale suspended cables. The technique is applied to resolve the problems of such high-frequency vibrations as the aeolian vibration. The vibration control device involves an absorber driven by a motor, and the dynamics of the controlled system is investigated numerically considering practical problems. Particular attention is paid to backlash at the driving that influences the effectiveness of control significantly, and to the time response of the controlled system that indicates how quickly the vibration decays after a change in the excitation. One of the proposed controllers involves the implementation of PID technique that enables the significant reduction in the value of cable displacement and acceleration during aeolian vibration, compared to the conventional vibration absorber. An extensive controller has also been proposed based on estimation of cable vibration frequency. The dynamic performance of the controllers is simulated using Simulink. Results also reveals the limitations in the control due to a practical problem like backlash. The main practical benefit from the study is that it provides information about the advantages and disadvantages of the control methodologies, and recommendation may be done for their application without building the controlled system.

Finite element analysis of a single conductor with a Stockbridge damper under Aeolian vibration

A finite element model is developed to predict the vibrational response of a single conductor with a Stockbride damper. The mathematical model accounts for the two-way coupling between the conductor and the damper. A two-part numerical analysis using MATLAB is presented to simulate the response of the system. The first part deals with the vibration of the conductor without a damper. The results indicate that longer span conductors without dampers are susceptible to fatigue failure. In the second part, a damper is attached to the conductor and the effects of the excitation frequency, the damper mass, and the damper location are investigated. This investigation shows that the presence of a properly positioned damper on the conductor significantly reduces fatigue failure.

Finite element analysis of a single conductor with a Stockbridge damper under Aeolian vibration

A finite element model is developed to predict the vibrational response of a single conductor with a Stockbride damper. The mathematical model accounts for the two-way coupling between the conductor and the damper. A two-part numerical analysis using MATLAB is presented to simulate the response of the system. The first part deals with the vibration of the conductor without a damper. The results indicate that longer span conductors without dampers are susceptible to fatigue failure. In the second part, a damper is attached to the conductor and the effects of the excitation frequency, the damper mass, and the damper location are investigated. This investigation shows that the presence of a properly positioned damper on the conductor significantly reduces fatigue failure.

Characteristics of the asymmetric Stockbridge damper

The Stockbridge damper (tuned mass absorber) is used on overhead transmission power lines to suppress wind-induced vibrations. These power lines get exposed to various types of wind motions that cause them to vibrate and this causes fatigue failure at the suspension clamp where the maximum stress occurs. Aeolian vibration is the most common wind motion that causes fatigue and eventually, failure to transmission lines. This paper presents the study of an asymmetric Stockbridge damper. A set of experiments were conducted on the damper according to the Institute of Electrical and Electronics Engineers (IEEE) 664 standards to evaluate the characteristics of the asymmetric Stockbridge damper. The results obtained revealed that the asymmetric damper is four degrees of freedom. The results also revealed a relationship between the mass and the magnitude of the resonance frequency.

Aeolian Vibration Control of Power Transmission Line Using Stockbridge Type Dampers — A Review

Due to its inherent low damping, a power transmission line is prone to wind induced vibration. Vibration control is needed to suppress the aeolian vibration of the transmission-line to reduce the fatigue and to extend its service life. Though patented in 1928, more than 90 years ago, the Stockbridge damper or its variants are still commonly used for vibration suppression of conductors in modern day power transmission systems because of their advantages of simple structure, low cost, reliable operation and effective vibration suppression. This paper offers a comprehensive review of the development, modeling, analysis, and design of the Stockbridge-type dampers and their applications in Aeolian vibration control of power transmission lines. A Stock bridge-type damper is a dumbbell-shaped device that consists of a short messenger cable with two masses at the ends and a clamp at the middle to attach to a conductor. The friction among the strands in the messenger cable dissipations energy. A Stock bridge-type damper is essentially a tuned mass damper. For the modeling of a Stockbridge damper alone, the classis linear mechanics analysis, the nonlinear analysis, and finite element method (FEM) are reviewed. For the modeling of the combined damper and conductor system, this paper mainly reviews the Energy Balance Principle (EBP) that is relatively easy to use and can obtain the energy dissipated by the damper. Two important design issues, the damper parameter sensitivity analysis and damper location optimization, are discussed in this paper. This paper also briefly reviews the experimentation and fatigue related to a Stockbridge damper. In addition, this paper provides an outlook of future development, analysis, and application of Stockbridge-type dampers for conductor vibration control.