An interactive load flow program

Abstract

An interactive load flow program (ILF) differs from a conventional load flow program in its interface with the user. By means of a display device the user specifies his input and the program presents its output. Such a program could serve a number of important uses in the power industry. A step in this direction is presented in this paper. The program described combines an AC load flow program with a display program. The results of the load flow are entered into a one-line diagram of the network which is displayed on a CRT screen. The change case input is handled at the CRT through use of two keyboards and a light pen. The operator can elect to display any section of the network diagram to analyze the case. In this he is also helped by limit violation reports, which can be displayed. The operator modifies the case by changing the structure of the network or the values of the load flow parameters. After he has made all changes, a new load flow is run and its results are again displayed. This cycle can be repeated as often as desired. The rapid response and the versatility of the CRT input devices make this program an ideal study tool. The paper describes the main structure of the program and discusses user interaction. A visual example of how the program performs is given. Copyright © 1972 by The Institute of Electrical and Electronics Engineers, Inc.