Superheated steam temperature is crucial for safety and economy of coal-fired power units. However

the large inertia and strong uncertainty of superheated steam temperature system make it difficult to control. To solve these difficulties

a cascade control structure based on modified active disturbance rejection control is proposed. The inner loop uses a conventional PI controller and the outer loop uses a modified active disturbance rejection controller. An engineering tuning method for modified active disturbance rejection control is provided

and a response curve to optimize the compensation time constant is designed to address the difficulty of obtaining the compensation time constant. Finally

the advantages of the proposed control strategy in tracking and disturbance rejection performance under large-scale variable loads are verified through comparative simulations and practical engineering applications. The operational data of engineering applications shows that the proposed method can ensure smaller maximum positive and negative deviations

average absolute deviation

and deviation standard deviation

which has significant advantages and potential for engineering applications.