GB188330A - Improvements in tidal-water-power plants - Google Patents

Abstract

188,330. Huguenin, A. Nov. 1, 1921, [Convention date]. Addition to 171,346. Tidal energy, utilizing.-In the tidal-power plant described in the parent Specification the asynchronous generator of each unit is synchronized during continuous running and is only asynchronous during the periods in which an alteration of speed is effected. In order to obtain a current of constant voltage and periodicity in spite of variation in speed due to variation of the head such variation may be counteracted during working either by an alteration of the electric connections, for example by changing the connection of the poles, or the variation in effective head may be counteracted by mechanical gearing. In order to avoid the use of synchronous condensers the asynchronous generator is synchronized for the continuous working by means of a known device. Fig. 3 shows diagrammatically such an arrangement having a direct current exciter p, the generator comprising a stator g<1> and rotor g<2> provided with a switch o for changing from asynchronous to synchronous working; polechanging switches n of known type for altering the number of poles are included in order to maintain the frequency at lower speeds. The turbines a, b, Fig. 1, for driving the generator g through gearing c, c<1>, d, d<1>, are provided with guide-vanes e, f hinged on vertical pins so that they may be used as upward-flow, or downwardflow turbines, or may be put out of action.