How can I performe a load scaling?
PowerFactory provides a built-in functionality to adapt the power of selected loads to result in the measured values at the beginning of a feeder. Using the attached example, the following steps explain the usual approach to perform the load scaling:
The initial load flow results in a value of 4.02 MW at the feeder; the measurement however shows a value of 3.5 MW.
1. Definition of the feeders: Right-click on the line (in general the branch element) close to the
up-stream cubicle (the element is then half selected) and click on Define/Feeder. Check the option Feeder is supposed to be operated radially.
2. Select the desired type of scaling (e.g. active power) in the Load Flow tab and enter the measured value which should be the result of the scaling (e.g. 3.5 MW).
3. All loads, which should be adapted, must be marked. Check in the according load elements the option Adjusted by Load Scaling in the Load Flow tab. In the attached example, the loads NS1 and NS2 will be scaled, NS3 is fixed to keep its nominal value (e.g. because of known/measured values).
4. To perform the load scaling, check the option Feeder Load Scaling in the Basic Options tab of the Load Flow Calculation command (ComLdf) and execute the calculation. The results of the feeder now should be as defined. To get the scaling factor, open the Relevant Objects for Calculation filter for feeder (ElmFeeder) and switch to the Flexible Data page. The calculation parameter c:scale shows the value, with which the selected loads are scaled.
5. To take over the scaling factor for each of the selected loads, press the Update Database button in the main icon bar.