Since the steam temperature control of direct steam generation(DSG) trough solar collector exhibits large time delay

non-linearity

uncertainty

and difficult accurate modeling

the conventional PID control scheme is difficult to achieve ideal control effect. To solve this problem

based on the idea of active disturbance rejection control(ADRC)

the virtual control variable is introduced. Firstly

the ADRC scheme is designed for the remaining part of the DSG trough solar collector steam temperature object after removing the pure time delay link

and the corresponding virtual control variable is obtained. Subsequently

the actual control variable is predicted by using the virtual control variable with the tracking differentiator(TD). Finally

the spraying water flow is controlled to regulate the steam temperature. The simulation results show that

the proposed ADRC scheme can overcome the changes of dynamic property and large time delay under different pressure conditions

and track the steam temperature rapidly and accurately without overshoot during the whole process. The control quality of the proposed ADRC scheme is significantly better than that of the conventional PID control scheme.