PowerWorld Viewer is a freeware program designed to make it easy to exchange power flow cases. You can view a solved power flow case graphically using animated one-lines.
With Viewer, you can view data, pan and zoom on one-line diagrams, contour data, and distribute your power system cases to others. Viewer does not, however, allow you to make any modifications to the viewed system, re-solve the flows in the network, or modify the graphical representation of the system. PowerWorld Simulator allows you to accomplish these tasks.
Some example one-lines are available in Texas A&M’s Electric Grid Test Case Repository.