Patent Application
20100262265
The subject matter disclosed herein relates to control systems, and, more specifically, to designing and executing logic on programmable controllers.
Control systems for processes, plants, and equipment, may include a wide variety of logic to configure how the control system monitors and controls the processes, plants and equipment. A control system may include one or more programmable controllers. To enable design of the logic for a controller and to provide easier configuration, the control system logic may be displayed in various forms on a graphical user interface (GUI).
The graphical user interface (GUI) may be accessible to a user, and the user may design the logic and configure the controller from the GUI. The GUI may present design of the control logic by presenting the logic in a standard format and/or programming language. Sequential Function Charts (SFC) is a programming language defined according to the International Electrotechnical Commission (IEC) 61131-3 standard. Such SFC control logic may not be executable or understood by certain programmable control systems of a controller.
Certain embodiments commensurate in scope with the originally claimed invention are summarized below. These embodiments are not intended to limit the scope of the claimed invention, but rather these embodiments are intended only to provide a brief summary of possible forms of the invention. Indeed, the invention may encompass a variety of forms that may be similar to or different from the embodiments set forth below.
In a first embodiment, a method includes receiving SFC logic on a physical computing device wherein the SFC logic includes Steps and Transitions and converting the Steps and Transitions to function blocks on the physical computing device. The method also includes uploading the function block logic from the physical computing device to a controller.
In a second embodiment, a physical computing device comprises a tangible machine-readable medium comprising code adapted to provide an SFC editor to a user, receiving first application code comprising an SFC model, convert the first application code to second application code comprising blockware, and output the second application code.
In a third embodiment, a system includes a programmable logic controller that includes function blocks executable to perform one or more control functions, wherein the function blocks are translated from a Sequential Function Chart model via a block library.
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
When introducing elements of various embodiments of the present invention, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
Embodiments of the present invention include techniques for executing Sequential Function Chart (SFC) as blockware (e.g., function blocks) in a programmable controller. Embodiments include receiving Sequential Function Chart (SFC) logic comprising Steps and Transitions, converting the Steps and Transitions of the Sequential Function Chart (SFC) logic to function block logic, and uploading the function block logic from a physical computing device to a controller. These Steps and Transitions may be designed according to the SFC Specification (IEC 61131-3). Function blocks of the function block logic generally include inputs (such as input variables), outputs (such as output variables), and logic operators (e.g., Boolean operators, numerical operators, etc.). In some embodiments, a block library may be provided that includes specific function blocks that provide mechanisms to convert Steps and Transitions of the SFC logic.
The illustrated process 14, turbine 16, and power generation component 18 may include any number of sensors 20 and actuators/motors 22. The sensors 20 may comprise any number of devices adapted to provide information regarding process conditions. For example, the sensors 20 may monitor temperature, pressure, speed, fluid flow rate, vibration, noise, exhaust emissions, power output, clearance, or any other suitable parameter. The actuators 22 may similarly include any number of devices adapted to perform a mechanical action in response to an input signal. For example, the actuators 22 may control a fuel injection rate, a diluent or water injection rate, a coolant rate, a power output level, a speed, a flow rate, a clearance, and so forth.
As illustrated, these sensors 20 and actuators 22 are in communication with the control system 12, such as through interfaces 24. The control system 12 may include one, two, three, or more controllers 26 (e.g., programmable logic controllers) that may operate in any manner suitable for monitoring and controlling the system 10. For example, such systems may be referred to as simplex (one controller), duplex (two controllers), triple module redundant (three controllers and referred to as “TMR”) and may provide any suitable redundancy model. The sensors 20 and actuators 22 may be in direct communication with any or all of the controllers 26. These devices may be utilized to operate process equipment. Indeed, they may be utilized within process loops that are monitored and controlled by the control system 12 and the controllers 26. In certain embodiments, the controllers 26 may be separate and/or integral with the process 14, the turbine 16, and/or the power generation component 18.
The computer 34 may be any suitable computer, such as a laptop, desktop, server, etc. In other embodiments, the computer 34 may be any portable electronic device capable of executing the design application 36. The computer 34 may include a display 35 to display various portions or screens of the design application 36 to the user 32. The display 35 may include a CRT display, an LCD display, an OLED display, an LED display, or any suitable display or combination thereof. Further, the computer 34 may include one or more processors 37 that may communicate with the memory 31 and execute the design application 36 and any other applications on the computer 34.
The computer 34 may be coupled to the controller 26 via a network 38. The network 38 may include any wired network, wireless network, or combination thereof, such as Ethernet, wireless Ethernet, etc. The controller 26 may include firmware 39 generally responsible for interpreting, compiling, and/or executing any control logic downloaded to the controller 26 from the computer 34 via the network 38.
To create control logic for the controller 26, the user 32 may start a new logic design or load an existing logic design in the design application 36. In one embodiment, the design application 36 may provide the user 32 with a Sequential Function Chart (SFC) diagram editor 40 for designing logic using the IEC 61131-3 standard (referred to as “SFC”). As described further below, the SFC logic created by the user 32, (which may be referred to as an SFC “data model”) may include a variety of “Steps” and “Transitions” to define logic that monitors and controls the system 10.
In such an embodiment, the firmware 39 of the controller 26 may be incapable of interpreting, compiling, and/or executing SFC logic application code generated by the SFC design editor 40 of the design application 36. For example, the controller 26 may be capable of only interpreting, compiling, and/or and executing “blockware” application code, e.g., logic defined according to function blocks and not the SFC logic (SFC data model) created by the user 32 using the SFC design application 40.
As described above, the user 32 may design and edit an SFC data model 47 (SFC logic) on the SFC design editor 40. When the user 32 has completed the desired SFC data model 47, the complier 42 may automatically execute. In some embodiments, the complier 42 may execute after any change to the SFC model 47. In other embodiments, the complier 42 may execute after completion of an entire new SFC model 47. In yet other embodiments, the complier 42 may execute upon initiation by the user 32. Upon initiation of the upload, the SFC data model 47 may be provided to the complier 42 (as shown by arrow 48). The complier 42 compiles the SFC data model 47 (SFC logic) to function blocks 44 (i.e., blockware), such as by using the block library 46. As described below, the compiler 42 may convert each Step and Transition of the SFC data model 47 to a function block 44. These function blocks 44 describe the logic of the SFC data model 47 in a format interpretable, compliable, and executable by the firmware 39 of the controller 26. As shown by arrow 49, the complier 42 outputs blockware 50 (comprising function block logic 44) from the design application 36. The blockware 46 may be uploaded to the controller 26 over the network 38.
As shown in
As described above, after the user 32 creates the SFC logic diagram 52, the SFC logic diagram 52 may be selected for upload to the controller 46. The complier 42 complies the SFC data model (SFC logic) depicted in SFC logic diagram 52 to function blocks 56, as illustrated by the blockware diagram 54.
As shown in
Additionally, the conversion of the various Steps and Transitions of the SFC model 47 may include the use of the block library 46. The block library 46 may include any number of specific function blocks that provide mechanisms for the blockware 50 in view of the converted SFC logic of the SFC model 47. For example, each block of the block library 46 may implement one or more SFC functions and define corresponding inputs and outputs for execution of these one or more functions. An embodiment of the block library 46 is provided below in Table 1:
It should be appreciated that some embodiments may use any or all of the block library 46 described above. Additionally, in some embodiments, additional blocks may be added to the block library 46 to facilitate compilation of the SFC data model 47 to the blockware 50. In other embodiments, the inputs and/or outputs of the blocks of the block library 46 described above may be modified for a specific implementation of a SFC.
The SFC data model 47 is provided to the compiler 42. As described above, the compiler 42 may access and use the block library 46 to compile the SFC data model 47 to blockware application code, such as by converting the Steps and Transitions of the SFC data model 47 to function blocks 56 as shown in
The blockware application code 82 includes the SFC blockware task application code 84 complied from the SFC Data Model 74. Additionally, in some embodiments, the blockware application code 82 may include traditional blockware application code 86, e.g., code not compiled from the SFC Data model 47. For example, the traditional blockware application code 86 may be created from a traditional blockware diagram editor 88, e.g., a blockware logic interface, executing on the computer 34. Finally, the downloaded blockware 82 is executed as a part of the controller runtime 88, e.g., after interpretation, compilation, and/or execution by the controller firmware 48. Advantageously, the firmware 39 of the controller 26 does not need to be modified to use the SFC data model 47.
Technical effects of the invention include converting IEC 61131-3 SFC logic to function block logic for use by a controller. Other technical effects include use of a block library defining specific function block mechanisms for converting the SFC logic to the function block logic.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
