International Journal of Electronics and Electrical Engineering ISSN : 2277-7040 Volume 2 Issue 8 (August 2012) http://www.ijecee.com/ https://sites.google.com/site/ijeceejournal/ 1 Life time enhancement of a Vacuum Interrupter for AC Smart Grid Applications Asaad Shemshadi 1,1 , Seyed Mohammad Tagi Bathaee 1 , Sima Jalali Kashani 1 , 1 Khaje Nasir Toosi University of Technology, Electrical & computer Department,Tehran, Iran Asaad Shemshadi, a.shemshadi@dena.kntu.ac.ir Abstract. A smart grid is a modern system combined from power system and a network of computers which communicate and process the data achieved from measuring centers located in the power system network. They achieve specific local goals such as: enhancement the reliability, fast and easy control of power network and on-line monitoring. To control the blocks of a smart grid (entrance or outage), HV, MV and LV switching actions frequently are needed. Nowadays Vacuum interrupters (VI) are the most widespread switching devices especially in LV and MV voltage levels (up to 38 kV), through their reliability, heavy duty and maintenance free characteristics. In this article, the important lifetime factors of a VI for smart grid applications will be discussed. Further more the closing and opening speed of a proposed circuit breaker mechanism, as the most important lifetime factor, will be so planned that an important enhancement in the total lifetime of the VI is achieved. Keywords: smart grid; vacuum interrupter; lifetime; power system; measuring center. 1 The corresponding author.