%0 Journal Article
	%A R. K. Singh and  P.K.Jain
	%D 2008
	%J International Journal of Electrical and Computer Engineering
	%B World Academy of Science, Engineering and Technology
	%I Open Science Index 17, 2008
	%T Ohmic Quality Factor and Efficiency Estimation for a Gyrotron Cavity
	%U https://publications.waset.org/pdf/15492
	%V 17
	%X Operating a device at high power and high frequency
is a major problem because wall losses greatly reduce the efficiency
of the device. In the present communication, authors analytically
analyzed the dependence of ohmic/RF efficiency, the fraction of
output power with respect to the total power generated, of gyrotron
cavity structure on the conductivity of copper for the second
harmonic TE0,6 mode. This study shows a rapid fall in the RF
efficiency as the quality (conductivity) of copper degrades. Starting
with an RF efficiency near 40% at the conductivity of ideal copper
(5.8 x 107 S/m), the RF efficiency decreases (upto 8%) as the copper
quality degrades. Assuming conductivity half that of ideal copper the
RF efficiency as a function of diffractive quality factor, Qdiff, has
been studied. Here the RF efficiency decreases rapidly with
increasing diffractive Q. Ohmic wall losses as a function of
frequency for 460 GHz gyrotron cavity excited in TE0,6 mode has
also been analyzed. For 460 GHz cavity, the extracted power is
reduced to 32% of the generated power due to ohmic losses in the
walls of the cavity.
	%P 869 - 872