Hi,
recently,i'm doing some experiment to convert from 3 phase balanced input to dq components to calculate the active power.
As you can see from the attached diagram,i've included the wattmeter to measure the active power drawn by the load(R=20 ohms) which shows 605Watts at steady state. But when i use the dq transformation and calculate the active power based on the formula P=VdId +VqIq
which is shown on the first graph ,P=V23*V21+V24*V22 ,it gives a value of 400W at steady state.Is there anything wrong with my assumptions or diagram?
Another question. for dq transformation, why the direct and quadrature component remain at a constant value despite of change in theta with time (theta=wt) Another question. for dq transformation, why the direct and quadrature component remain at a constant value despite of change in theta with time (theta=wt) .Thanks
Regards
alvin
recently,i'm doing some experiment to convert from 3 phase balanced input to dq components to calculate the active power.
As you can see from the attached diagram,i've included the wattmeter to measure the active power drawn by the load(R=20 ohms) which shows 605Watts at steady state. But when i use the dq transformation and calculate the active power based on the formula P=VdId +VqIq
which is shown on the first graph ,P=V23*V21+V24*V22 ,it gives a value of 400W at steady state.Is there anything wrong with my assumptions or diagram?
Another question. for dq transformation, why the direct and quadrature component remain at a constant value despite of change in theta with time (theta=wt) Another question. for dq transformation, why the direct and quadrature component remain at a constant value despite of change in theta with time (theta=wt) .Thanks
Regards
alvin
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