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impedance_dump -- Dump impedance and line equation data from powerflow link objects. This is useful for debugging parameters or tracking down issues in the model.


object impedance_dump {
	char256 filename "";
	char32 group "";
	timestamp runtime 'INIT';
	int32 runcount 0;


The impedance_dump object produces a dump of the impedances and line equation information at link objects in powerflow.

The output format of the impedance dump fits the line equation format of William Kersting's "Distribution System Modeling and Analysis" book. I.e., the impedance_dump outputs the [math]\displaystyle{}a, b, c, d, A, B[/math] matrices of the equations:

[math]\displaystyle{} \begin{bmatrix} VLG_{in} \\ I_{in} \end{bmatrix} = \begin{bmatrix} a & b\\ c & d\end{bmatrix}\cdot{}\begin{bmatrix}VLG_{out} \\ I_{out}\end{bmatrix}[/math]

[math]\displaystyle{}VLG_{out} = A\cdot{}VLG_{in}-B\cdot{}I_{in}[/math]

with the [math]\displaystyle{}b[/math] matrix typically representing the traditional impedance of a line.


Property name Type Description
filename char256 XML output file to save the impedance information.
group char32 Search criteria for objects of interest. See Finding Object for syntax. Defaults to "all link objects".
runtime timestamp Time to run the impedance dump. By default, this is after the first successful time interval has completed (e.g., commit of the first timestep).
runcount int32 Number of times the impedance dump has executed (see Remarks).


Currently, the impedance_dump object will only execute once, at the selected `runtime`. If multiple dumps are desired, a player or some other interface would need to update the `runtime` and reset the `runcount` values. Also note that the file in `filename` will be overwritten, so if this route is used, something must externally rename or copy the XML prior to running the next impedance dump.

See also

Powerflow module

Powerflow User's Guide