Study on economics of depth peak-shaving for 1000MW ultra supercritical unit

Abstract

With the increase of the demand for deep peak regulation of power grid, large-capacity units have the advantages of strong peak regulation capacity. 1000MW units have been widely involved in deep peak regulation. In the process of deep peak regulation, the actual working condition of the unit deviates greatly from the designed working condition, and the unit efficiency decreases significantly, making the unit economy deteriorate seriously, especially in the 1000MW grade unit. In this paper, a 1000MW unit depth peak adjustment is experimentally studied and its economic indexes are calculated. Then, by analyzing the test data, the optimization Suggestions for the operation of the unit during the depth peak adjustment are put forward:(1)Improve the opening of the high pressure switch of the unit to reduce throttling loss and improve the unit efficiency; (2)Increase the reheat steam temperature to ensure the stable operation of the reheat steam temperature at 620 °C of the full load section; (3) Keep a circulating pump running at a low speed during deep peak adjustment to reduce power consumption.