Timestamps of output measurements in dynamic calculations


#1

Hi. I have used some “Dynamic Calculator” adapters to calculate some derived variables from the original phasors that I receive from the PMUs. For example, specific angular differences between PMUs. I store the calculated measurements in the historian (PPA) for further use. It seems that the openPDC uses the local clock to timestamp the calculated measurements.

Is it possible the use the timestamps of the input measurements in the adapter instead of the local clock? Is there a parameter that I can use in the connection string to do that?

Here is an example of connection string I’ve used to calculate am angular difference between PPA:1378 and PPA:1369, with a wrapping in the range [-180;+180], storing the result in the PPA:2342:

VariableList={x=PPA:1378;y=PPA:1369}; OutputMeasurements=PPA:2342; ExpressionText=if((x-y)<-180.0,(x-y+360.0),if((x-y)>180.0,(x-y-360.0),x-y)); FramesPerSecond=60; LagTime=1; LeadTime=5; allowPreemptivePublishing=false; useLocalClockAsRealTime=false

Thanks.


#2

Hi Marcelo,

I just added a timestampSource parameter to the DynamicCalculator yesterday.

The default value for the new parameter is Frame so all you should need to do is install the latest nightly build version of the openPDC.
http://www.gridprotectionalliance.org/NightlyBuilds/openPDC/Beta-VS2012/Synchrophasor.Installs.zip
http://www.gridprotectionalliance.org/NightlyBuilds/openPDC/Beta-VS2012/Synchrophasor.Binaries.zip

Thanks,
Stephen


#3

Hi Stephen. Great! I’ll try it and let you know.

Thanks.