| According to the recent energy structure of our country, it's long-term task that large capacity thermal power units have to be used in peak regulation. To two-shift operation units, accelerating the speed of startup or shutdown is the objective demand of electric network peak regulation and the reasonable requirement of decreasing thermal loss when startup or shutdown, increase operation economical efficiency, but it can also increase the unit's life loss and become the dangerous factor of two-shift operation units. Therefore we can improve the peak regulation through two methods: the first is improving the equipment mostly in order to adapt the acceleration and startup or shutdown frequently; the second is choosing reasonable startup or shutdown style, control every target in safe range at the same time of acceleration through improving operational procedure.This paper studied the appraisement of steam turbine optimized startup or shutdown, the choice of optimal temperature rising rate and the research of life management system of 300MW steam turbine rotor based on the actual requirement of in site rotor life management, it also illustrated the possibility of optimizing to startup or shutdown and the methods of strengthen local life management. Mainly:1. This paper analyzed the background of rotor life research, and studied the problem in life management recently (including nestification of low-cycle and high-cycle fatigue loss, interaction of high temperature creep and low-cycle fatigue, reliability analysis and design of low-cycle fatigue), and analyzed the develop direction of life management in order to illustrate the importance of this topic.2. This paper studied the life management from rotor life calculation and optimum criterion by analyzing the calculation of rotor temperature field, stress, rotor life and rest life.3. Aimed at the cold start and the hot start with initial temperature 300 C in 11 operation modes, this paper studied the optimal temperature rising rate and calculate respectively, and analyzed the temperature rising rate impact on the startup or shutdown time, the stress margin and the life loss rate. It also analyzed the impact of the temperature rising rate on the stress value and life loss rate.4. This paper analyzed the structure (especially the rotors and the gland sealing system) of a 300MW unit in YangLuo power plant. Based on the #2 unit startup curve in this plant, the construction of the rotors and the parameters off-design condition, this paper calculated the stress of the gland sealing part of the high pressure rotor, studied the life distribution and management, and analyzed AGC varying duty impact to rotor safety. At last, this paper illustrated the measures of increasing rotor life loss. |
