SUMMARY This Report describes work undertaken in an attempt to establish the feasibility of using models to investigate the performance of gravel arresters for aircraft. The experiments were designed using the techniques of physical similarity and dimensional analysis, Tests were carried out with 1:9.3 scale models of Lightning and Canberra aircraft in two types of sand, and the results compare...

This paper consist of two sections: control and stabilizing approach for chaotic behaviour of converter is introduced in first section of this paper for the removal of harmonic caused by the chaotic behaviour in current converter. For this work, a Time- Delayed Feedback Controller (TDFC) control method for stability chaotic behaviour of buck converter for switching courses in current control mo...

This article proposes a new method for the optimal design of zinc oxide arresters based on electric field distribution column using smart algorithms and finite element analysis. prevents premature aging tablets, especially initial final tablets column, which have higher voltage gradient than other parts arrester, subsequently increases sustainability network. The spacer height, fiberglass layer...

conclusions in this study, some characteristics that had a positive impact on the success of a manager in a hospital surge situation were identified. these characteristics ought to be taken into account when appointing hospital administrators and designing training programs for hospital administrators with the aim of being better prepared to face disasters. background hospital administrators pl...

In this paper, the effectiveness of lightning overvoltage protection cables in high voltage overhead cable lines has been analyzed. Because level, are protected by surge arresters and metallic sheath earthing. However, practice, quite a lot cases electricity-evoked damage to outer sheaths observed, proving that used is insufficient. As result, exposed environmental factors, especially moisture ...

This paper introduces the indicators for surge arrester condition assessment based on the leakage current analysis. Maximum amplitude of fundamental harmonic of the resistive leakage current, maximum amplitude of third harmonic of the resistive leakage current and maximum amplitude of fundamental harmonic of the capacitive leakage current were used as indicators for surge arrester condition mon...

The high amplitude and steep overvoltage generated by the breaking of vacuum circuit breaker in wind farm damages inter-turn insulation transformer. There is a certain difference between simulation results traditional reignition model measured overvoltage. It necessary to improve simulate condition transformer more accurately then select appropriate protection measures. In this paper, based on ...

Computer modeling with the EMTP code has been applied to several configurations and earthing practices in use in various countries to show the effect of any differences in the dispersion (sharing) of a lightning stroke current among the available paths for the earth-seeking lightning current. Simplifying assumptions have been made to some details of the configurations to focus on the main diffe...

In a hydroelectric power plant or in a pumping station in order to avoid sudden large increase of pressure due to instantaneous valve closure sometimes a surge tank is installed. The height of surge tank is designed by the highest possible water level during the operation. The theoretical treatment of oscillation in a surge tank is difficult because of the non-linearity of friction term in the ...