English title

Natural gas is transmitted at high pressure levels. For industrial and domestic consumptions, this pressure should be reduced. Usually, mechanical valves accomplish this process. Turbo-expanders can replace these equipments and reduce gas pressure at city gate gas pressure reduction stations as well. Besides, they can recover the huge amount of high pressure gas energy and drive electrical generators. But, because of instantaneous varying of domestic consumptions, environment temperature and other effective parameters, turbo-expander inlet gas pressure and mass flow-rate vary with time and consequently, the extracted power has time variant specification. These variations are transferred by coupled generator to the power distribution network and cause voltage flicker at the point of common coupling (PCC). In this paper, we represent a proper model for flicker study of turbo-expander driven synchronous generator in the power distribution network. Also, we assess the amount of voltage flicker at the PCC and show the produced flicker rate is dependent on the inlet gas specification and the power distribution network parameters.