Abstract

Solar direct steam generation (DSG) systems are well suited for process steam applications and are able to provide steam at the pressure required by common industrial processes. Nevertheless, reliable control has always been a challenge for solar DSG system hindering its wider adoption. In this paper, a control strategy for solar DSG systems is presented. The control strategy is based on proportional-integral-derivative (PID) control theory combined with model-based feedforward control. Experimental data demonstrate that the control strategy provides good performance in terms of stability and setpoint tracking. The error in setpoint tracking for the load pressure controller is shown to be as low as ±0.005 MPa under real life conditions. The said strategy is currently implemented in two commercially operating plants providing solar steam for industrial processes.

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