Negative Power Output

[Bal_M]

I have defined an Inverter from CEC database using the parameter values directly. However, I am getting negative power output. The defined values are listed below

cec_inverter.Paco=3606980

cec_inverter.Pdco=3708310

cec_inverter.Pso=7573.76

cec_inverter.Vac='630'

cec_inverter.Vdco=1100

cec_inverter.C0=-0.00000000473641

cec_inverter.C1=0.00000304621

cec_inverter.C2=0.000146486

cec_inverter.C3=-0.0000950682

cec_inverter.Pnt=264.05

cec_inverter.Vdcmax=1300

cec_inverter.Idcmax=3371.19

cec_inverter.Mppt_low=915

cec_inverter.Mppt_high=1300

[cwh...@sandia.gov]

The model can produce negative AC power if the DC input power is less than Pnt, which represents the inverter's self-consumption. In this case I would expect the negative AC power would be perhaps -100W. If the negative AC power is much less than -100 W, I would look upstream at the DC calculations.

Best regards,

Cliff

[Bal_M]

Thank you for the response. I have updated to exact configuration and now getting positive power. I just wanted to confirm using a module and Inverter directly CEC database should be okay?

[cwh...@sandia.gov]

Should be OK, yes, but it's good practice to always check the results. There's a few physical relationships you should see: DC power is roughly linear with irradiance, DC voltage is roughly linear with cell temperature, AC power is roughly linear with DC power.

Best regards,

Cliff