HV transformer loss > MV transformer loss

[Daksha B]

Could someone help me with why my simulation results look like this? I have never seen the HV xfmr loss > MV xfmr loss. My inputs are - 

MV xfmr loss = 0.87% + 0.13%

HV xfmr loss = 0.45% + 0.05%

 

Could it have something to do with weather file/weather at the site location? 

[André Mermoud]

IIn PVsyst, the transformer losses are defined as a sum of

- the ohmic losses, proportional to the square of the current or power, calculated at each hour of the simulation. The annual ohmic loss value  is not identical to the specified loss fraction, which is specific to a reference power. See the help "Project design > Array and system losses > AC ohmic loss from inverter to injection point".

- the iron loss, a fixed constant loss, permanent as soon as the transformer is connected to the grid. This may give a high contribution  as it is permanent and doesn't depend on the PV production. See the help "Project design > Array and system losses > External transformer losses"

 

[dtarin]

In PVsyst, the inputs for HV transformer are in MVA. Ensure that the percentages shown match what you have there. PVsyst should then calculate correctly. Your MV waterfall loss looks appropriate for the inputs.