Papers by Keyword: Structure Control

Abstract: The wind power is increasingly developed, and the tropical weather condition is a challenge for flexible wind turbine structure. It is essential to get the structure response of wind turbine under typhoon conditions, and then solutions to reduce the load should be found. This article firstly discusses characteristics of typhoon suitable for wind turbine loads calculation, and then a simplified model with two degrees of freedom is got in two directions separately, according to the experiences of high-rise structure to mitigate vibration and theory of vibration absorber, passive TMD systems are put to the wind turbine structures in longitudinal and lateral direction. After that a medium complicated aero-elastic software FAST-SC is used to simulate transient and also fatigue conditions, the tower top displacement and tower base bending moment are evaluated, TMD systems can help reduce the transient load and fatigue loads of flexible wind turbine structures.

Abstract: In this paper a new one-dimensional continuous model was proposed for Shape Memory Alloys (SMAs), which can be applied in the continuous dynamic loading system. After a literature review over the constitutive modeling of SMAs, an improved continuous model considering the influences of the various strain rates of SMAs was developed, which based on a series of experiments. The results of the experiments were used to validate the effectiveness of the proposed model. The constant factors in the model were determined according to the measured experimental data. The parameters in the model were also numerically analyzed and the numerical results matched well with experimental results. The results of the simulation showed that the developed model can effectively represented the relationship between the strain and stress of SMAs under dynamic loading and can be better applied in structure control.

Abstract: The equation of motion for the coupled system of structure—MR-TLCD is formulated by Lagrange equations in this paper. Wind load response of a single-degree-of-freedom structure with MR-TLCD is obtained by time domain method. From the point of view energy dissipation force of MR-TLCD, the Simple Bi-State (SBS) control algorithm control algorithm is developed based on energy dissipation. By applying semi-active and passive control strategies, the controlled wind load response of the coupled system excited by wind load are numerically simulated. The peak value and root mean square value of the displacement and acceleration are obtained and the control effects of the system using the SBS algorithms. The results showed that the wind load responses of the coupled systems could be controlled effectively by applying the MR-TLCD.

Abstract: According to the poor performance about conductivity and cycle properties of conductive polyaniline (PANI) electrode material. The structure control techniques were used and the C/PANI compound electrod materials and fibrous PANI electrod materials were prepared.The electrochemical performance of PANI with different structure was examined .The examination results indicated: The structure control methods have obvious influnce on the electrochemical performance of PANI. The improvement of PANI structure may enhance the penetration of electrolyte and the intercalation of electrolyte ion. At the 2mA discharge current , the max capacitance of PANI-C and PANC-S is 435F/g and 387F/g, respectively .The capacitance retention rate of PANI-C and PANC-S after 500th cycle is 77% and 96%. The ion diffusion impedance of PANI-S material was lowest and show best capacitance and cycle performance.