Temperature Control of Line-Focus Solar Collectors

Solar thermal electric power and industrial process heat systems may require a constant outlet temperature from the collector. This temperature may be efficiently maintained by adjusting the circulating fluid flow rate. Using frequency response techniques, simple relations are developed which relate controller tuning constants to collector construction and field layout. Successful controller tuning is shown to be a compromise between good response at high flow rates and stability at low flow rates. The rules of thumb are then tested by performing dynamic numerical simulations of a collector row with flow rate control.