ACTUATOR FOR HVAC SYSTEMS AND METHOD FOR OPERATING THE ACTUATOR

• US 20110153089A1
• Filed: 07/03/2008
• Published: 06/23/2011
• Est. Priority Date: 07/03/2008
• Status: Active Grant

• Current Assignee: Belimo Holding AG
• Original Assignee: Belimo Holding AG
• Inventors: Tiemann, Dirk, Gort, Urs
• Granted Patent: US 8,521,332 B2
• Time in Patent Office: Days
• US Class Current: 700/276
• CPC Class Codes: F24F 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/54 using one central controller connected to several sub-controllers
• CPC Class Codes: F24F 11/58 using Internet communication
• CPC Class Codes: G05B 19/056 Programming the PLC
• CPC Class Codes: G05B 2219/13063 Synchronization between modules
• CPC Class Codes: G05B 2219/13076 Interprete in pc a ladder diagram, use of sequence engine
• CPC Class Codes: G05B 2219/13148 Object oriented programming

Abstract

An actuator for an HVAC system comprises a stored model definition defining an HVAC control application, and an element library including a variety of stored model elements and controller modules (D, E) having instructions for controlling a processor of the actuator. The controller modules (D, E) include model elements and are configured to control the sequential order of their execution. The controller modules (D, E) are further configured to propagate any external data input (S66′, S68′) to their model elements prior to executing their first model element, and to propagate any data output (S63, S65, S67, S69) to external components after executing their last model element. The controller modules (D, E) are instantiated in different threads of execution, so that data is interchanged asynchronously between instantiated controller modules (D, E) and neither temporal dependencies nor change of value links are imposed on components of the control application.

Claims

1. An actuator (10) for HVAC systems (1), the actuator (10) comprising a network interface (20) for connecting the actuator (10) to a communication network (2), a bus interface (30) for connecting the actuator (10) to a sensor/actuator bus (3), a data store (12), and a processor (11) connected to the data store (12);

wherein the actuator (10) further comprises;

a loader (102) configured to receive via the communication network (2) and store in the data store a model definition (15) defining an HVAC control application;

an element library (16) including a variety of stored model elements (4011, 4021) comprising instructions for controlling the processor (11), and controller modules (401, 402, 403) configured in each case to control the sequential order of execution for associated model elements (4011, 4021) referenced by the respective controller module (401, 402, 403), to propagate external data input to its associated model elements (4011, 4021) prior to beginning the execution of the model element defined first in the sequential order, and to propagate data output from its associated model elements (4011, 4021) to the outside of the respective controller module (401, 402, 403) at completion of the execution of the model element defined last in the sequential order; and

a model interpreter (17) configured to implement based on the model definition (15) the control application for execution on the processor (11), by instantiating controller modules (D₁ F) and their associated model elements (A, B, C) as referenced by the model definition (15), assigning at least one instantiated model element to a device (4) attached to the sensor/actuator bus (3), and instantiating the controller modules (D, E) in each case as a different thread of execution, so that data is interchanged asynchronously between instantiated controller modules (D, E).

2. The actuator (10) of claim 1, wherein the model elements (4011, 4021) are in each case configured to read input data from one or more defined data input buffers (i) associated with the respective model element, and to write output data to one or more defined data output buffers (o) associated with the respective model element;

the model interpreter (17) is further configured to link, based on linking information included in the model definition (15), output buffers of instantiated model elements (A, B, C) to input buffers of instantiated model elements (A₁ B, C); and

the controller modules (401, 402, 403) are configured to propagate in each case, upon completion of the execution of model elements (4011, 4021) referenced by the respective controller module, data values from the model element'"'"'s output buffer (o) to a linked input buffer (i) of a model element referenced by the respective controller.

3. The actuator (10) of claim 1, wherein the model definition (15) includes identifiers of model elements (4011, 4021) and parameter values applicable in each case to the respective model element;

the model interpreter (17) is configured to instantiate in each case the model element from the element library (16) based on the identifier and parameter values; and

the controller modules are configured to execute in individual processing intervals assigned in each case to the respective controller module.

4. The actuator (10) of claim 1, wherein the model definition (15) includes graphical user interface data associated with model elements (4011, 4021) referenced by the model definition (15), the graphical user interface data including at least position information for positioning on a display a graphical representation (400) of the respective model element.

5. The actuator (10) of claim 1, wherein at least some of the stored model elements are configured to be operable in different modes, the modes being selectable through setting at run-time of a state associated with an instantiation of the respective model element.

6. The actuator (10) of claim 1, further comprising a server module (19) configured to transmit to a web browser a graphical representation (400) of the control application via the communication network (2) based on the model definition (15), to transmit to the web browser for display in the graphical representation (400) input/output values associated in each case with a mode! element referenced by the model definition (15), to receive from the web browser parameter values associated in each case with a model element referenced by the model definition (15), and to store in the actuator (10) the parameter values assigned to an instantiation of the respective model element (A₁ B, C).

7. The actuator (10) of claim 1, wherein the stored model elements (4011, 4021) include elements representative of at least one of controller, PID controller, two point controller, limiter, tinier, Boolean logic module, time period management module, heating curve module, filter module, floating average calculation module, flip flop module, input selector module, constant value module, comparator, mathematical operation module, state checking module, error catching module, and error trigger module.

8. The actuator (10) of claim 1, wherein the network interface (20) is configured for communication according to the Internet Protocol over an Ethernet communication network;

the sensor/actuator bus (3) includes one of MP-Bus and BACnet-bus;

the model definition (15) is defined in a mark-up language;

the stored model elements (4011, 4021) are defined in Java byte code;

the processor (11) is a Java processor configured to execute Java byte code; and

the loader (102) is further configured to store in the actuator (10) at least one HTML version of the model definition (15).

9. A method for operating an actuator (10) of an HVAC system (1), the method comprising:

storing in the actuator (10) a model definition (15) defining an HVAC control application;

storing in the actuator (10) an element library (16) which includes a variety of model elements (4011, 4021) and controller modules (401, 402, 403), the model elements (4011, 4021) and controller modules (401, 402, 403) comprising instructions for controlling a processor (11) of the actuator (10);

implementing in the actuator (10), based on the model definition (15), the control application for execution on the processor (11), by instantiating from the element library (16) controller modules (D, E) and associated model elements (A, B, C) as referenced by the model definition (15), assigning at least one instantiated model element (A, B, C) to a device (4) attached to a sensor/actuator bus (3), and instantiating the controller modules (D, E) in each case as a different thread of execution; and

executing the control application by the respective controller modules (D, E) in each case controlling the sequential order of execution for associated model elements (A, B, C) referenced by the respective controller module (D, E), propagating external data input to its associated model elements (A, B, C) prior to beginning the execution of the model element defined first in the sequential order, and propagating data output from its associated model elements (A, B₁ C) to the outside of the respective controller module (D, E) at completion of the execution of the model element defined last in the sequential order, so that data is interchanged asynchronously between instantiated controller modules (D, E).

10. The method of claim 9, wherein the model elements (A, B, C) read input data from one or more defined data input buffers associated with the respective model element (A, B, C), and write output data to one or more defined data output buffers associated with the respective model element (A, B, C);

output buffers of model elements (A, B₁ C) are linked to input buffers of model elements (A, B, C), based on linking information included in the model definition (15); and

, upon completion of the execution of model elements (A, B, C) referenced by a respective controller module (D, E), data values are propagated in each case from the model element'"'"'s output buffer to a linked input buffer of a model element (A, B, C) referenced by the respective controller (D, E).

11. The method of claim 9, wherein the model elements (A, B₁ C) are instantiated from the element library (16) in each case based on an identifier and respective parameter values included in the model definition (15);

and instantiated controller modules execute in individual processing intervals assigned in each case to the respective controller module.

12. The method of claim 9, wherein the model definition (15) includes graphical user interface data associated with model elements (4011, 4021) referenced by the model definition (15), and a graphical representation (400) of a respective model element is positioned on a display based on position information included in the graphical user interface data.

13. The method of claim 9, wherein selected at run-time is a state associated with an instantiation of a model element (A, B₁ C), the state setting the respective model element (A₁ B₁ C) to operate in one of at least two different modes.

14. The method of claim 9, wherein, based on the model definition (15), a graphical representation (400) of the control application is transmitted from the actuator (10) via the communication network (2) to a web browser;

input/data output values, associated in each case with a model element (4011, 4021) referenced by the model definition (15), are transmitted from the actuator (10) to the web browser for display in the graphical representation (400);

parameter values, associated in each case with a model element (4011, 4021) referenced by the model definition (15), are received in the actuator (10) from the web browser; and

the parameter values are stored in the actuator (10) assigned to an instantiation of the respective model element (A₁ B₁ C).

17. The method of claim 10, wherein the model elements (A, B₁ C) are instantiated from the element library (16) in each case based on an identifier and respective parameter values included in the model definition (15);

and instantiated controller modules execute in individual processing intervals assigned in each case to the respective controller module.

18. The method of claim 10, wherein the model definition (15) includes graphical user interface data associated with model elements (4011, 4021) referenced by the model definition (15), and a graphical representation (400) of a respective model element is positioned on a display based on position information included in the graphical user interface data

19. The method of claim 10, wherein selected at run-time is a state associated with an instantiation of a model element (A, B₁ C), the state setting the respective model element (A₁ B₁ C) to operate in one of at least two different modes.

20. The method of claim 10, wherein, based on the model definition (15), a graphical representation (400) of the control application is transmitted from the actuator (10) via the communication network (2) to a web browser;

input/data output values, associated in each case with a model element (4011, 4021) referenced by the model definition (15), are transmitted from the actuator (10) to the web browser for display in the graphical representation (400);

parameter values, associated in each case with a model element (4011, 4021) referenced by the model definition (15), are received in the actuator (10) from the web browser; and

the parameter values are stored in the actuator (10) assigned to an instantiation of the respective model element (A₁ B₁ C).

15. A computer program product comprising computer program code means for controlling a processor (11) of an actuator (10) of an HVAC system (1) such that the actuator (10) receives via a communication network (2) a model definition (15) defining an HVAC control application;

stores the model definition (15) in a data store (12) of the actuator (10);

implements based on the model definition (15) the control application for execution on the processor (11) of the actuator (10), by instantiating from a stored element library (16) controller modules (D, E) and associated model elements (A, B, C) as referenced by the model definition (15), assigning at least one instantiated model element (A₁ B₁ C) to a device (4) attached to a sensor/actuators bus (3), and instantiating the controller modules (D₁ E) in each case as a different thread of execution, and executes the control application by controlling the sequential order of execution for associated model elements (A, B, C) referenced by the respective controller module (D, E), by propagating external data input for the respective controller module (D₁ E) to its associated model elements (A, B, C) prior to beginning the execution of the model dement defined first in the sequential order, and by propagating data output from the associated model elements (A, B, C) to the outside of the respective controller module (D, E) at completion of the execution of the model element defined last in the sequential order, so that data is interchanged as between instantiated Controller modules (D, E).

16. The computer program product of claim 15, comprising a computer-readable medium containing the computer program code means therein.