Modern electric power systems are a combination of complex objects with various factors of mutual influence, and therefore, to solve any issues relating to the design and subsequent operation of these objects, the development and use of specialized software is relevant. This paper contains information about the functional capabilities of the Excel application “Selecting Switches” developed by the authors, aimed at automating calculations made by students of electric power specialties while completing term papers and dissertations, as well as specialists from design institutes.
Keywords: switch, electric power systems, automation, application.
The algorithm of the application and its implementation. The application is based on the algorithm shown in Figure 1, for the implementation of which the standard functions of logical conditions “IF” are used, which have the corresponding values “TRUE” and “FALSE”.
Work with the application. The process of automated selection of a switch is divided into several stages. At the first stage, in the columns "
" and "
", Figure 2, it is necessary to set the minimum values of voltage and current, respectively. To do this, left-clicking on the icon 
, of all the options presented in the database, it is necessary to leave “checkmarks” only near those that are not lower than the values 
and 
, accordingly. After selecting the required values, the application using the filter function will leave for consideration by the User only those switches whose voltages and currents correspond to the initial data. An indicator of data filtering is the icon 
. To remove filtering from one or another column, click on the icon and select the «Remove Filter»... command.
Fig. 1. Block diagram of the application algorithm
The next step in the selection is to enter the calculated data. For this, the User needs to move to the right side of the application using the “slider”. The input fields are cells with a gradient green fill. Note that when entering data, the user needs to be especially careful. However, if for some reason incorrect data has been entered, the application will notify you of this, Figure 3, and further calculation will not be carried out until the User corrects the entered data.
Fig. 2. General view of the application
In the event that all the data has been entered correctly, the User can familiarize himself with both the subtotal for each of the conditions of the test and the final result of the test of the switches. For the final consideration, it is necessary to take only those switches (in accordance with their numbers) that pass through all the test conditions, Figure 4.
At the time of release, the application contained a database of catalog data on 382 switches.
Fig. 3. Example of incorrect data entry
Fig. 4. An example of the formation of a list of switches that passed under all conditions
Hardware requirements. The following minimum hardware and software are required for this application to work: a) any IBM-compatible computer with a standard hardware configuration; b) the operating system MS Windows XP and higher; c) the installed package of Microsoft Office 2007 and higher.
