Voltage Drop and Flicker Tool

The voltage Drop and Flicker Analysis (V-Drop) tool began as a DSTAR Engineering Toolbox program to calculate voltage drop and flicker for three-phase services where each customer or load is served radially by a separate service cable from the transformer. In addition, V-Drop can calculate the impact of large motor starting or other flicker loads elsewhere on the feeder.

VDFT main screen

The user clicks on the graphic objects to enter data in V-Drop. Transformer and cable data can be selected from data set up by the Administrator, or the user can input data directly.

V-Drop also allows the user to model the primary radial system back to the substation to determine the primary side flicker seen by other loads on the same feeder. Primary modeling is not mandatory, however, and the user can opt to define the primary impedance at the distribution transformer in terms of the short circuit strength, or choose to ignore the primary system altogether.

Built-In Data

The V-Drop tool has several lists of data which are customized for each utility using the program. These are:

  • Secondary cable impedances for various sizes and installation configurations.
  • Transformer data
  • Primary overhead construction data
  • Primary underground cable data
  • Motor data

The pull-down lists used in the tool are based on these customized parameters. like ther toolbox programs, the custom data lists are password protected so that they can only be updated by a designated program administrator.

V-Drop was created, modified, enhanced in the following projects: P7-1, P8-4

An Office 2007 compatible version is available in: 11-0