Processing

Please wait...

Settings

Settings

Goto Application

1. WO2020114668 - DEVICE AND METHOD FOR CONTROLLING AN ORIFICE OF A VALVE IN AN HVAC SYSTEM

Note: Text based on automatic Optical Character Recognition processes. Please use the PDF version for legal matters

[ EN ]

Claims

1 . A method of controlling an orifice of a valve ( 1 0) in an HVAC system ( 1 00) to regulate the flow (F) of a fluid through a thermal energy exchanger (2) of the

HVAC system ( 1 00) and adjust the energy transfer rate (0 of the thermal energy exchanger (2) in response to a demand value (d ), the method comprising:

controlling the orifice of the valve ( 1 0) in a first mode of operation (M 1 ) where the flow (F) of the fluid through the thermal energy exchanger ( 2 ) is regulated within efficiency constraints on the energy transfer rate (0 with respect to a first efficiency threshold value ( Tj ) , the efficiency constraints being determined by comparing a temperature difference AT = Tin - Tmt , between a supply temperature

Tin of the fluid entering the thermal energy exchanger ( 2) and a return

temperature Tout of the fluid exiting the thermal energy exchanger (2 ), to the first efficiency threshold value (F7j ) ; and

upon receiving an override signal (OS), controlling the orifice of the valve ( 1 0) in a second mode of operation (M2) where the flow (F) of the fluid through the thermal energy exchanger ( 2 ) is not regulated with respect to the first efficiency threshold value (FTX ) .

2. The method of claim 1 , wherein controlling the orifice of the valve ( 1 0) in the second mode of operation ( M2) comprises regulating the flow (F) of the fluid through the thermal energy exchanger ( 2) within the efficiency constraints on the energy transfer rate (0 with respect to a second efficiency threshold value (FT2) , the second efficiency threshold value (FT2) being lower than the first efficiency threshold value ( Jj) .

3. The method of one of claims 1 or 2, wherein the method further comprises adjusting efficiency threshold values ( 7j, 2)for the efficiency constraint, using at least one of: a flow rate (F) of a fluid flowing on a primary side (101) of the thermal energy exchanger (2), a flow speed of the fluid on the primary side (101) of the thermal energy exchanger (2), a flow rate of a fluid flowing on a secondary side (23) of the thermal energy exchanger (2), a flow speed of the fluid on the secondary side (23) of the thermal energy exchanger (2), a temperature of the fluid on the secondary side (23) of the thermal energy exchanger (2), a humidity of the fluid on the secondary side (23) of the thermal energy exchanger (2), and an entropy of the fluid on the secondary side (23) of the thermal energy exchanger (2).

4. The method of one of claims 1 to 3, wherein the method comprises generating (S100) the override signal (OS), if controlling the orifice of the valve (10) in the first mode of operation (M1) does not attain the demand value (d) within a determined first duration of time.

5. The method of one of claims 1 to 4, wherein the method comprises cancelling (S200) the override signal (OS), if controlling the orifice of the valve (10) in the second mode of operation (M2) has attained the demand value (d) for a determined second duration of time.

6. The method of one of claims 1 to 5, wherein the override signal (OS) is generated by an electronic circuit ( 1 4) of a thermostat ( 5) unit comparing a current temperature to a target temperature defined by the demand value (d).

7. The method of one of claims 1 to 6, wherein regulating the flow (F) of the fluid through the thermal energy exchanger ( 2) within the efficiency constraints on the energy transfer rate ( Q ) comprises adjusting the orifice of the valve ( 1 0) in order to attain the demand value (d), if the temperature difference AT = Tjlt— Tout is at or above the efficiency threshold value {FT FT2) , and adjusting the orifice of the valve ( 1 0) in order to maintain a current flow (F) of the fluid through the thermal energy exchanger ( 2), if the temperature difference AT Tjn - Toul is below the efficiency threshold value ( FTX , FT2 ) .

8. The method of claim 1 , wherein the override signal (OS) is indicative of a current flow (F) of the fluid through the thermal energy exchanger ( 2 ) below a minimum flow rate threshold, said minimum flow rate threshold being dependent on a temperature of the fluid; and controlling the orifice of the valve ( 1 0) in the second mode of operation (M2 ) comprises adjusting the orifice of the valve ( 1 0) to increase the flow ( f ) of the fluid through the thermal energy exchanger ( 2).

9. The method of one of claims 1 to 8, wherein the demand value (d) comprises at least one of: a target temperature, a target orifice of the valve ( 1 0), a control value for the valve ( 1 0), a target flow rate (F) , a target energy transfer rate (Q) , and a control value for an actuator ( 1 1 ) actuating the valve ( 1 0).

10. A control system (1) for controlling an orifice of a valve (10) in an HVAC system (100) to regulate the flow (F) of a fluid through a thermal energy exchanger (2) of the HVAC system (100) and adjust the energy transfer rate ( Q ) of the thermal energy exchanger (2) in response to a demand value (d), the control system (1) comprising an electronic circuit ( 14) configured to:

control the orifice of the valve (10) in a first mode of operation (M1 ) where the flow (F) of the fluid through the thermal energy exchanger (2) is regulated within efficiency constraints on the energy transfer rate (Q) with respect to a first efficiency threshold value ( 7j), the efficiency constraints being determined by comparing a temperature difference AT = Tin -Toni, between a supply temperature

Tjn of the fluid entering the thermal energy exchanger (2) and a return

temperature Tout of the fluid exiting the thermal energy exchanger (2), to the first efficiency threshold value ( 7J) ; and

upon receiving an override signal (OS), control the orifice of the valve (10) in a second mode of operation (M2) where the flow (F) of the fluid through the thermal energy exchanger (2) is not regulated with respect to the first efficiency threshold value ( 7J) .

1. The control system ( 1 ) of claim 10, wherein the electronic circuit ( 14) is configured to control the orifice of the valve (10) in the second mode of operation (M2) by regulating the flow (F) of the fluid through the thermal energy exchanger (2) within the efficiency constraints on the energy transfer rate (Q) with respect to a second efficiency threshold value (FT2) , the second efficiency threshold value (FT2) being lower than the first efficiency threshold value ( 7j).

12. The control system (1) of one of claims 10 or 11 , wherein the electronic circuit (14) is configured to adjust efficiency threshold values (FT FT2) for the efficiency constraint, using at least one of: a flow rate (F) of a fluid flowing on a primary side

(101) of the thermal energy exchanger (2), a flow speed of the fluid on the primary side (101) of the thermal energy exchanger (2), a flow rate of a fluid flowing on a secondary side (23) of the thermal energy exchanger (2), a flow speed of the fluid on the secondary side (23) of the thermal energy exchanger (2), a temperature of the fluid on the secondary side (23) of the thermal energy exchanger (2), a humidity of the fluid on the secondary side (23) of the thermal energy exchanger (2), and an entropy of the fluid on the secondary side (23) of the thermal energy exchanger (2).

13. The control system (1) of one of claims 10 to 12, wherein the electronic circuit (14) is configured to generate the override signal (OS), if controlling the orifice of the valve (10) in the first mode of operation (M1 ) does not attain the demand value (d) within a determined first duration of time.

14. The control system (1 ) of one of claims 10 to 13, wherein the electronic circuit ( 14) is configured to cancel the override signal (OS), if controlling the orifice of the valve (10) in the second mode of operation (M2) has attained the demand value

(d) for a determined second duration of time.

15. The control system (1) of one of claims 10 to 14, wherein the electronic circuit (14) is implemented in a thermostat unit and configured to generate the override

signal (OS) by comparing a current temperature to a target temperature defined by the demand value (d).

16. The control system (1) of one of claims 10 to 15, wherein the electronic circuit ( 14) is configured to regulate the flow (F) of the fluid through the thermal energy exchanger (2) within the efficiency constraints on the energy transfer rate (0) by adjusting the orifice of the valve ( 10) in order to attain the demand value (d), if the temperature difference AT = Tin -Toul is at or above the efficiency threshold value

(FT FT2) , and adjust the orifice of the valve (10) in order to maintain a current flow (F) of the fluid through the thermal energy exchanger (2), if the temperature difference AT = Tm-Tota is below the efficiency threshold value ( FTX,FT2 ).

17. The control system ( 1 ) of claim 10, wherein the electronic circuit (14) is configured to generate the override signal (OS), if a current flow (F) of the fluid through the thermal energy exchanger (2) is below a minimum flow rate threshold, said minimum flow rate threshold being dependent on a temperature of the fluid; and control the orifice of the valve (10) in the second mode of operation (M2) by adjusting the orifice of the valve ( 10) to increase the flow (F) of the fluid through the thermal energy exchanger (2).

18. The control system (1) of one of claims 10 to 17, wherein the electronic circuit (14) is configured to process a demand value (d) comprising at least one of: a target temperature, a target orifice of the valve (10), a control value for the valve

(10), a target flow rate (F) , a target energy transfer rate ( Q ) , and a control value for an actuator (11) actuating the valve (10).

19. A computer program product comprising a non-transient computer readable- medium having stored thereon computer program code configured to control a processor (14) of a control system ( 1 ), for controlling an orifice of a valve (10) in an HVAC system (100) to regulate the flow (F) of a fluid through a thermal energy exchanger (2) of the HVAC system (100) and adjust the energy transfer rate ( Q ) of the thermal energy exchanger (2), in response to a demand value (d), such that the processor ( 14) executes the steps of:

controlling the orifice of the valve (10) in a first mode of operation (M1 ) where the flow (F) of the fluid through the thermal energy exchanger (2) is regulated within efficiency constraints on the energy transfer rate ( Q ) with respect to a first efficiency threshold value ( 7j), the efficiency constraints being determined by comparing a temperature difference AT = Tjn -Tout, between a supply temperature Tin of the fluid entering the thermal energy exchanger (2) and a return

temperature Tmt of the fluid exiting the thermal energy exchanger (2), to the first efficiency threshold value ( 7J) ; and

upon receiving an override signal (OS), controlling the orifice of the valve (10) in a second mode of operation (M2) where the flow (F) of the fluid through the thermal energy exchanger (2) is not regulated with respect to the first efficiency threshold value (F7j) .