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Results

The calculated optimal values are listed in a table. The table is shown after having

selected the menu option "Analysis Optimal Separation Points - Results Tables Elements". A summary is shown with menu option "Analysis OptimalSeparation Points - Results Tables Summary".

If the calculation parameter "Set optimal values" is active the original data of thenetwork is modified according to the results.

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Theory

The goal of the implemented procedure is to eliminate all network meshes by

changing the network topology. Usually, there are a huge number of possibletopology states. This procedure chooses the one topology that minimizes networklosses, considering all activated constraints and without creating isolated sub-systems.

To the beginning of the procedure all switchable elements of the consideredvoltage level are switched on. After that, an iterative process follows, that containsthe following core:

1. Load flow calculation

2. Determination of the element with the lowest apparent power from thequantity of switchable and not yet worked off elements.

3. The found element is switched off.

4. If the system contains an isolated part or any constraint is violated, theelement is switched on again and is marked as worked off.

The iteration continues, until the quantity of switchable and not yet worked offelements is empty. Usually the resulting system contains no mashes. If this is notdesired, one must deactivate the field "switchable" of the elements that must notbe switched off. The field "switchable" exists only for lines and cables.

If the option Prevent overloaded elements is activated, the procedure containsan additional check. An element is switched off only if the number of overloaded

elements isnt increasing. If the option Prevent limit violations of node voltages isactivated, elements are switched off, only if the number of voltage violations isntincreasing.

If the procedure is not able to eliminate all meshes, there may be too manyconstraints. The optimization problem contains the following constraints:

Maximum element loadings

Node voltage limits

Set of not switchable elements

The user can activate or deactivate the constraints using the options in thecalculation parameter dialog. Maximum element loadings and node voltage limitsare set by the Load Flow parameter dialog (Analysis Load Flow Parameters).

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