Abstract:

In recent years, the wind and PV power curtailment is becoming more and more serious, and the demand for deep peaking capacity of coal-fired power plants is also increasing. In this paper, the flexibility transformation of 350MW super-critical cogeneration units was studied combined with the relevant policies of thermal power unit's deep peak shaving compensation in North China. The optimal scheme suitable for our factory was obtained through analyzing several mainstream flexibility transformation technologies, comparing the advantages and disadvantages, investment costs and operating costs of various technologies, evaluating the effect of unit flexibility on later operation combined with the compensation for peak adjustment in the region. The results show that the low-pressure cylinder zero output heating technology is the lowest cost scheme coping thermoelectric decoupling. When the unit price of standard coal is below 700 yuan per ton, the unit is not suitable for peak adjustment and should be loaded with more load; and when the price of the standard coal is above 700 yuan per ton, it is possible to reduce unit load to reduce loss through peak regulation.

Key words: cogeneration unit, flexibility transformation, deep peak regulation, wind power curtailment, photovoltaic energy curtailment