Increase of the energy efficiency of the reversible bulb unit of a tidal power station by regulating the rotational speed

Conclusions

• 1. A synchronous induction motor-generator provides reliable regulation of the rotational speed of the unit in wide limits; in this case regulation of the reactive power is also provided within permissible limits and the operating conditions of the unit improve simultaneously with the system.

• 2. For conditions of the Kislaya Guga tidal power station, regulation of the rotational speed within ±30%n_n makes it possible to increase the efficiency of the unit in a forward turbine regime (double regulation) by 4.5% and in a reversed turbine regime (single regulation) by 11.2%. In addition to an increase of the efficiency of the unit, regulation of the rotational speed increases the maximum power at heads less than the design.

• 3. During operation of the SIMG of the Kislaya Guba station the power effect of using rotational speed regulation for the unit as a whole decreases somewhat in connection with a decrease of the efficiency of the SIMG at low speeds.

• 4. Regulation of the rotational speed makes it possible to use units with single regulation at plants with a wide variation of the head and also provides a reduction of the level of unsteady loads in the water passageway.

• 5. It is necessary to continue works on the creation and detailed investigation of more powerful SIMGs.