Evaluation of possible variants of backup methods of starting reversible pump-turbine motor-generator sets at the zagorsk pumped-storage station in a pump mode

Conclusions

• 1. As a rule, a backup starting device differing fundamentally from the primary one is provided for at multiple-set PSSs with high-power reversible sets (single capacity of 100 MW and more) regardless of the type and number of the primary starting devices.

• 2. The use as a backup method of asynchronous connection of high-power reversible sets to the total line voltage cannot be recommended, since such connection has a negative effect on the stability of the power pool and, furthermore, requires taking special design measures which lead to a considerable increase of cost of the motor-generator with a simultaneous decrease of its reliability.

• 3. Under conditions of an operating station, when selecting the backup starting method it is necessary to take into account the impossibility of a major rearrangement of the electrical equipment and expansion of its composition.

• 4. The results of tests at the Zagorsk PSS and calculations at the Moscow Power Institute confirm the prospects of using as a backup theasynchronous-synchronous method of starting from an adjacent reversible set, which provides simplicity and reliability of asynchronous starting and minimum current loads at the stage of synchronous frequency acceleration.