Abstract: In order to achieve the goal of “double carbon”, alleviate the peak shaving pressure after the high proportion of new energy is incorporated into the power grid, and improve the flexibility of coal-fired units, the implementation scheme of the flexibility technology of circulating fluidized bed cogeneration units is discussed.Taking the 2×300 MW subcritical circulating fluidized bed unit of a power plant in Shanxi as an example, the research on the flexible operation of coal power is carried out from the perspective of heating period, non-heating period and full period. The flexibility transformation carried out in the heating period adopts the joint implementation and comprehensive transformation technical route of various peak shaving technologies such as low pressure cylinder micro output, high and low bypass combined heating and electric boiler, which improves the flexibility operation ability of circulating fluidized bed coal-fired power unit in the heating period. Aiming at the defect of insufficient peak regulation of cogeneration coal-fired power units in non-heating period, the peak regulation technology of furnace pressure fire with high parameter heat storage mode is adopted, and the near-zero depth peak regulation test and discussion of furnace pressure fire are carried out. At the same time, combined with the indirect peak shaving technology of the industrial park that can be applied throughout the year, a comprehensive transformation technical route for improving the flexibility of 300 MW subcritical circulating fluidized bed coal-fired power units is proposed. In short, the circulating fluidized bed cogeneration unit can improve the operation flexibility of the unit through the low-pressure cylinder micro-output operation heating transformation technology, high and low pressure bypass combined heating technology and electric boiler technology during the heating period. The technology of pressurized fire peak shaving provides a reference path for improving the flexibility of circulating fluidized bed cogeneration units in non-heating period. At the same time, the implementation of this technology is closely related to the equipment status, auxiliary equipment configuration and equipment controllability automation level of the unit. Improving the operation level and controllability of coal-fired power units is the basic requirement for realizing the flexibility of unit operation. The inter-industrial park steam supply can indirectly achieve peak regulation throughout the year. The combined heating period and non-heating period peak regulation technology further improves the comprehensive transformation route of CFB coal-fired power units, and provides technical reference for circulating fluidized bed cogeneration coal-fired power units that need to improve operational flexibility.