ENHANCEMENT OF MAXIMUM PERMISSIBLE CONDUCTOR TEMPERATURE OF 400 KV TRANSMISSION LINES

摘要

The quantum of power that a given EHV AC transmission line can safely carry depends on its thermal and stability limit. With the growth of the Indian 400 kV network and adoption of new technologies like FACTs, series compensation etc., the stability limits are being enhanced and made close to thermal limits of transmission lines. Under such a scenario, enhancement of thermal limits of existing and future transmission lines is considered desirable so as to increase the line loadability. Increasing the thermal limit of the transmission lines by enhancement of maximum allowable conductor temperature is also considered to offer advantage under emergency situations where the transmission lines may be loaded more due to absence of adequate alternate paths. This also would facilitate reduction in number of new lines to be constructed offering some relief for ever increasing right of way problems. The paper presents the studies conducted by POWERGRID for enhancement of maximum permissible temperature of 400 kV lines. Salient observations and results of techno-economic evaluation of increasing the maximum permissible temperature of the conductor for 400 kV transmission lines and possible solutions thereof have been presented in the paper.