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As a new actuator driven by Ampere force, Electro Magnetic Force driving Actuator (EMFA) is applicable to medium-high-voltage system with powerful output force, long stoke, simple structure and high reliability. In the paper, a new type of EMFA for 126kV VCB with single break is proposed on the basis of the mature manufacturing technology of 126kV vacuum interrupter. The model of EMFA is established...
This paper focused on a fast mechanical switch applied in 2kV hybrid DC contactor. An integrated design of vacuum switch based on Permanent Magnetic Actuator (PMA) is proposed. The stainless steel bellows is removed to avoid vacuum failure caused by air leakage and eliminate restriction of bellows' fatigue life compared to conventional vacuum switch. Both monostable structure and compact springs'...
Based on theoretical analysis and experimental research short-circuit electromagnetic forces of three-phase medium voltage (MV) earthing switches (ES) with different motion forms and different structural arrangements of ground loop have been studied. And the influence of electromagnetic force under correspondent various conditions on short-circuit making performance is discussed in detail as well...
A coupled fluid-mechanical dynamics analysis method is presented in this paper. A commercial simulation package is used for mechanical dynamics calculation, which employs user-developed dynamic-link library files as routine interface to enable data exchange with gas pressure calculation. This part is responsible for the calculation of mechanical motion, including the tripping of trip trigger, releasing...
Manufacturing process performances become a key issue for reliability improvement. In order to decreasing loss of production due to machine stopping, to achieve this goal to maintain the equipments in operational condition, make products quickly, economically and with high quality. This requirement can be satisfied by implementing appropriate maintenance strategies, Condition based maintenance (CBM)...
ICs bonding reliability at High Temperature (HT) application is considered. Namely results of investigations of bond ball lift failure mode category at post HT stresses Wire Bond Pull (WBP) tests for AlAu intermetallic interface at Tamb>150degC are presented in submitted paper. Simplified model of reliability risk assessment on the base of impact of such input factors as application temperature,...
To satisfy the requirement of controlling and protection of modern power grid, it is necessary to develop the fast switchgear switching quickly as the executive device. The advances of repulsion and permanent magnetic mechanism are combined fully, the hybrid fast operating mechanism constructed with electromagnetic repulsion and permanent magnetic mechanism was designed in the paper. The switching...
The objective of this paper is to improve the fatigue life of a contact spring pin in a 126 kV vacuum circuit breaker (VCB). Firstly, the fatigue life of the contact spring pin during the opening or closing operation of the 126kV VCB is analyzed. Secondly, an orthogonal experimental method is used for the improvement of the fatigue life of the contact spring pin, in which three impact factors are...
SF6 is a potent greenhouse gas and one of the promising alternatives is CO2. So this paper took CO2 rotating arc chamber as research object. The influence of the breaking angle and the magnetic field on the chamber was analyzed theoretically. Ansoft Maxwell software was used to simulate the magnetic field distribution in order to analyze the influence of the factors. Those factors are the number of...
As the worldwide demand for cybersecurity-trained professionals continues to grow, the need to understand and define what cybersecurity education really means at the college or university level. Given the relative infancy of these efforts to define undergraduate cybersecurity programs, the panelists will present different perspectives on how such programs can be structured. They will then engage with...
This work compares the control performance of two embedded control systems for controlling the angular position of a DC servomotor with nonlinear load: an arm with variable mass. The first control system uses an IO PID (Integer order Proportional Integral Derivative) controller, while the second employs a FO (Fractional Order) PID controller. Those control systems are embedded via a cRIO (compact...
The need of designing tactile sensors for machines and robotic systems has become crucial with the increase of the tasks related to human. This work proposes a silicone embedded, low profile piezoelectric sensor array that is suitable for applications where tactile sensing and force localization is needed. The developed sensor has 3 piezoelectric ceramics (PZT) placed in 1×3 array and consists of...
There are BBots (BristleBots) consist of a single and double vibration motor design. A single-actuated robot agent is more preferable due to its lower cost and energy consumption. Some studies reporting and modeling the linear motion single-actuated BBots are present in the literature. On the other hand, few of them included an explanation on its rotational motion. In this study, the planar motion...
We proposed a hybrid powered ankle exoskeleton. It can be able to supply positive mechanical power to the user during the swing phase of gait. The hybrid powered ankle exoskeleton was composed of a pair of compressed springs and a cable-driven actuator fasted to the shin. It was lightweight, and permitted the cable-driven actuator to provide the forces at the biological level to the ankle joint. Meanwhile...
The purpose of this study was to explore the relationship between grip strength and inter-muscular coordination of the forearms and hands. Twenty-four healthy young volunteers participated in the experiment. The subjects were instructed to grip hydraulic hand dynamometer with five force levels-maximal voluntary contraction (MVC), 70% MVC, 50% MVC, 30% MVC and without any contraction. Muscle activity...
In this paper, we proposed a sensor structure that can be used to measure the tactile force of robot fingertip. The structure of the sensor was composed of a cylinder-shaped finger and a circular base. First, we analyzed the relationship between the contact position and the stress with elastic mechanics theory. Then the corresponding spline curve algorithm was designed to calculate the contact position...
A method utilizing one Phase-shifted Fiber Bragg Grating (PS-FBG) and adaptive particle swarm optimization (APSO) algorithm has been proposed to simultaneously measure the spatial multiple axial stresses, including axial stress and transversal stress. The swarm success rate based dynamic adaptive strategy for the adjusting of inertia weight has been introduced to balance the exploration and exploitation...
The thumb and index finger are important digits to performed dexterous and complex manipulation of objects. However, the local muscle fatigue will induce the capacity of force production and impair the precision motor control of the thumb and index finger. This study focused on the exercise-induced local muscle fatigue influencing the COP (center of pressure) area, the SD and the PA (projection angle)...
The postural instability was observed in patients following-stroke during standing, showing an altered center of mass acceleration (COMacc). This study aimed to investigate the effects of stroke on fluctuation and complexity of COMacc during quiet standing. Eleven stroke survivals and eleven gender- and age-matched healthy subjects participated in this experiment. The COMacc series in anteroposterior...
In this paper, one fiber Bragg grating (FBG) vibration sensor is proposed and the application of weak signal processing based on Duffing oscillator model in optical fiber vibration sensors is studied. Frequency response and amplitude sensitivity experiments are all carried out to verify the characteristics of this FBG vibration sensor. By calculating the maximum Lyapunov exponent, these experiment...
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