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Model Issues: Documenation of LoadResponseCharacteristic exponents

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Documenation of LoadResponseCharacteristic exponents 


Suggest improvement to documenation of LoadResponseCharacteristic.pVoltageExpoent on its intended usage and mathematical equation.

Voltage exponents are only used if the LoadResponseCharacteristic.exponentModel is "true".   If so, then the voltage exponents are specified and used to compute load as  cim:SvFlow.p = Pnominal * (cim:SvVoltage.v/cim:BaseVoltage.nominalVoltage)**cim:LoadResponseCharacteristic.voltageExponent


* is "multiply"
/ is divide
** is "raised to power of"
cim:SvFlow object is the flow at the terminal of the EnergyConsumer (See CIM definition)
cim:LoadResponseCharacterisitic is from EnergyConsumer.LoadResponseCharacteristic
cim:SvVoltage is from the connected TopologicicalNode

I think that Pnominal should correspond to an EnergyConsumer attribute, but I don't know which one, possible pFixed?  Note UCTE profile does not exchange the nominal value, just the solved value.

Simlar description needed for qVoltageExponent, pFrequencyExponent, and qFrequencyExponent

SvFlow.p = pNominal * (frequency/(nominal frequency))**pFrequencyExponent

Note that both voltage and frequency exponents could be used together so the full equation would be:

SvFlow.p = Pnominal * (voltage/(base voltage))**pVoltageExponent * (frequency/(base frequency))**pFrequencyExponent

I think all these calculations flow from the basic definitions, but documenting how they work together make is much clearer.   We could even do this in a diagram instead of as documentation on the attributes themselves.

Proposed Resolution


Issue Status





(2) Normal 

Assigned To


Due Date



Kurt.HunterNo presence information (3/8/2009 1:26 PM): Added to CIM issues list as issue # 1211.

Related Issues


Date Created

Version: 2.0 
Created at 3/5/2009 5:53 PM  by kendall.demaree 
Last modified at 3/8/2009 1:26 PM  by Kurt.Hunter