ONE-LINE DIAGRAM PROGRAM
The TRANSMISSION 2000® One-Line Diagram (OL) program provides a graphical input and output interface to power system application programs such as power flow and short circuit. OL provides for the computerized construction, modification, and display of one-line diagrams of electrical power systems. You may draw, inspect, and change diagrams using a suitable graphics display on any computer running Microsoft Windows (Version 3.1) and obtain hard copies on any hard-copy device supported by Windows. Once you have constructed a system diagram, you may use it to initiate action in and present numeric results from the TRANSMISSION 2000® Power Flow (PFLOW) or Short Circuit (SC) programs in a clear visual format. You may use PFLOW, SC, or other programs with the same system one-line diagram.
We designed the One-Line Diagram program specifically for electric power systems. It is not a general-purpose drafting package. Instead, it is designed to make maximum use of the information already available in the power flow and short circuit data. You may also display network data on the diagram. The basis for a diagram is the system description given in the network data. The network data define the buses, lines, generators, transformers, loads, inductors, and capacitors in the system and their interconnections. Normally, the results from a solved PFLOW case, or from SC for a particular fault application or applications, are requested from OL or saved for display on the one-line diagram. Although numerical results from a particular PFLOW solution or SC fault are sometimes used to create a drawing, the drawing layout is based on the network data. Therefore, the results from other solutions for the same or a similar system configuration may be presented on the drawing.
OL is a fully conforming Windows program. If you are familiar with Windows, then you should be immediately comfortable with its commands and conventions. Even if you are not familiar with Windows, we are confident that you will like the ease-of-use provided by the pull-down menus and graphical user interface. If you prefer a command line interface, you will find that we have also included this option. One of the primary benefits of Windows is that each program readily interfaces with all the other programs. For example, it is easy to take a graphic from OL and include it in a report or document. That's how we added the figure above to this document. The figure below used OL's ability to copy any portion of the diagram to the clipboard. We pasted it from there into this document.
Two major advantages to Windows are its printer support and the help system. The help system allows us to have a completely cross-referenced version of the manuals on line and available at all times. Windows printer and plotter support means that if your printer or plotter has a Windows driver available, then you will be able to print diagrams on it. We sometimes see good drawings rendered on devices that we didn't even know existed. If you are lucky enough to have a high-quality color output device, you can produce color diagrams.
Graphics Features
Interactive commands specify the positions of the buses on a drawing of the entire system. After this, OL will select default positions for the branches, symbols, and text. In some cases, the resulting picture will be acceptable, but usually altering crossed lines and overlapping buses, repositioning lines and text, and so on are necessary to make the drawing neater. Using OL's menus, making these changes is easy. When you finish the diagram, you can save it in a "graphics file" for future use. If you solve a modified case with PFLOW or SC, the new results may be integrated into the original drawing, either temporarily or permanently. While we have greatly improved these functions over the years, they have been available in OL since we introduced this type of program to the personal computer environment in 1984. The following functions are newer additions:
- All objects (buses, lines, transformers, loads, etc.) can be placed at any orientation. They are not restricted to all horizontal or all vertical positioning. However, if you want to impose this restriction, you can do so.
- The program allows for simultaneous display of up to four different fonts and size combinations on a single diagram. You could display the text for buses in a bold times roman font and the text for lines as italic courier. You may select the fonts from the list of all fonts available to Windows.
- You can display objects in any color that you like. You may also select from a virtually unlimited list of line styles.
- You can scale symbols to any size desired. If you really dislike our symbols, you can create your own (or have us do it for you) and substitute them for the ones we provide.
- You can modify the individual attributes of any object or text item. If you would like to show something different for a particular item, you can.
Interface to Power System Network Applications
We explicitly designed OL to be an interface for other power system network applications. The idea is that users can readily identify operations and functions that they would like to perform from OL. Results are then displayed on the one-line diagram. You can point to a line with the mouse and outage it, then point to a bus and apply a fault. The results of these actions can be displayed immediately without user intervention. Thus both the input and output for applications such as power flow and short circuit can be through the diagram.
Unlike other one-line diagram interfaces in which you are restricted to a list of commands predefined by the program's designer, you can define both the results to be displayed and the commands to be issued to the applications.
It is also possible to connect OL to your own application. This might be your own power flow or short circuit program or some other network program that can be easily represented on a one-line diagram. To connect OL to an analytical program three conditions must be met:
- The program needs to be able to read a series of commands from a file.
- The program needs to be able to generate a set of ASCII tables with the results to be displayed on the diagram. The contents of these tables are user defined. Any program that has a simple report generation capability should be able to produce these tables.
- If OL is to display data automatically without any user interaction with the program, then your program must continuously look for a file with commands that it is to execute. If your program has a command file capability and a report generation capability, then this is the only feature that needs to be added to complete the interface to OL.
Unique Features
In addition to the array of features listed above, TRANSMISSION 2000® One-Line Diagram has several important features that are unique to the CAI program. These features were inspired by experience with previous versions of the program. Just as this experience cannot be matched, these features cannot be matched.
Text Cells By now you have probably used a spread sheet program. In these programs you specify a formula and the program displays the value computed from the specified formula. OL has a similar capability. Each object (bus, line, transformer, etc.) has a specified number of Text Fields or Cells associated with it. You specify the contents of each field by specifying the fields or functions of fields in the results data base file that you want to display. When OL loads the data to be displayed, the results of the desired computations are displayed on the diagram.
Style Sheets The ability to specify exactly what you want on the diagram is great. However, if you had to re-specify it every time you wanted to display a different set of results, it could become tedious. Fortunately, you can create a "style sheet" to store your desired displays. Like a style or a template in a word processor, these store all of the specifications for each type object. All you need to do is to select the desired style sheet. Of course we provide a set of standard style sheets with the program. If you like the way we have specified the results for display, you might never create your own style sheet.
Language Underlying OL is a language processor. This processor provides the functions you use when you specify items you wish to display on the diagram. It also supplies much more since it is a complete AC-like language. You can use it to write programs to process the information on the diagram. For instance, assume that you are interested in finding all the locations at which the voltage is out-of-range. You can write a little program to display each of the buses in a startling color (say hot pink). Of course a command language goes with a command line to allow you to input or store your programs. While you probably won't write a power flow using the language underlying OL, you do have the possibility of doing many creative things.
Operating Requirements
OL runs on Intel-based Personal Computers running Microsoft Windows. Two megabytes (Mb) of conventional and extended random access memory and a hard disk are required. A numeric coprocessor is not required but will increase the execution speed if present.
Either the CAI TRANSMISSION 2000® Power Flow program or Short Circuit program may be required for interactive use of or to generate results for display by the One-Line Diagram program. Other programs may be used with OL as outlined above.
Pricing Information
The single-copy price of the TRANSMISSION 2000® One-Line Diagram program includes one year of warranty, maintenance, and upgrade service. Multiple copy discounts, corporate licenses, rentals, and follow-on maintenance contracts are available. The program is supplied under an irrevocable, restricted license; copies of the license agreement are available for review. A demonstration package is available. It includes a sample copy of the program and instructions. The manual is available on the demonstration diskettes. A printed copy of the User's Reference Manual and the User's Tutorial are available. Please call us for up-to-date prices.
Training
Training on the operation and use of this program is available at either our location or yours. CAI will also provide consulting services related to the program. For example, you may find it desirable to have CAI personnel construct your initial diagrams, since this is a one-time investment of labor. Please call us for more information and pricing.
Other Programs in the TRANSMISSION 2000® Series
The TRANSMISSION 2000® One-Line Diagram Program is only one of the programs CAI offers for personal computer use. Power Flow, Power Flow Reduction & Data Conversion, Constrained Economic Dispatch, Short Circuit, Short Circuit Reduction, Protection Analysis, Line Constants, and Transient Stability programs are also available. If you are interested in platforms other than personal computers, you should consider CAI's CAPE series.
Ordering and Additional Information
To place an order or obtain additional information, please contact:
- Stephen S. Miller, P.E.
- Commonwealth Associates, Inc.
- P.O. Box 1124
Jackson, MI 49204-1124 - Tel.: (517) 788-3676
Fax: (517) 788-3003 - E-mail: Stephen S. Miller