Оценка технической возможности и целесообразности использования паровой турбины ПГУ-450 для регулирования частоты в энергосистеме

Abstract

A binary combined cycle plant (CCP) with the twin power unit configuration includes two active load control components: a gas turbine and a steam turbine. At present, CCPs are actively involved in frequency control in the power system. High load pickup and decreasing rates in combination with a low inertia impart high maneuverability indicators to the gas turbine, due to which it plays the leading role in the CCP power output control system. On the other hand, owing to a low dependence of the steam turbine efficiency on the current load and its high maneuverability due to using the storage capacity of the heat-recovery steam generator drums, the steam turbine can also be used in controlling the power system frequency. The article presents the results from modeling the PGU-450 power unit participation processes in controlling the power system frequency on the power unit’s computerized training simulator model with active involvement of the CCP steam turbine in adjustment of the CCP power output in the initial (most complex) load variation stage in accordance with the power system requirements through using the heat stored in the drums of heat- recovery steam generators. As a result of the accomplished studies, the technical feasibility and advisability of the proposed technology are shown. The technical advisability of actively involving the CCP steam turbine in control of frequency by using feed-forward control of the steam turbine is stemming from its high maneuverability due to a significant storage capacity of the steam generator drums, and the economic feasibility is due to the fact that both the steam turbine and gas turbine efficiencies change only slightly in changing the load within the required CCP power output variation limits.