US 12,281,802 B2
Method and control unit for controlling a control valve controlling a flow of heat transfer fluid into a thermal energy extraction unit
Per Rosén, Lund (SE); Jacob Skogström, Lomma (SE); Fredrik Rosenqvist, Helsingborg (SE); Bengt Lindoff, Bjarred (SE); and Helen Carlstrom, Bjarred (SE)
Assigned to E.ON SVERIGE AB, Malmo (SE)
Appl. No. 17/755,743
Filed by E.ON SVERIGE AB, Malmo (SE)
PCT Filed Oct. 27, 2020, PCT No. PCT/EP2020/080188
§ 371(c)(1), (2) Date May 6, 2022,
PCT Pub. No. WO2021/089370, PCT Pub. Date May 14, 2021.
Claims priority of application No. 19207690 (EP), filed on Nov. 7, 2019.
Prior Publication US 2022/0381449 A1, Dec. 1, 2022
Int. Cl. F24D 10/00 (2022.01)
CPC F24D 10/003 (2013.01) 14 Claims
OG exemplary drawing
 
1. A method for controlling a control valve, wherein the control valve is configured to control a flow of heat transfer fluid to a thermal energy extraction unit, wherein the control valve has a predetermined lower flow limit below which the control valve is experiencing hysteresis, the method comprising:
receiving and reviewing a demand signal for the control valve;
checking if the demand signal for the control valve is indicative of setting the control valve in a hysteresis interval for the control valve; and
upon the demand signal is indicative of setting the control valve in the hysteresis interval, alternatingly setting the control valve in an open state above the hysteresis interval or setting the control valve in a closed state.