Energy Management > Inverter temperature

[julmou]

Good morning,

I have two questions about the "Inverter temperature" section, when we go to Energy Management.

1. When is an inverter considered indoor? What about the containerised solutions such as provided by SMA? See photos below. Indoor? Outdoor?
2. Also I don't understand the last parameter "Increase Acc to Glob Inc, $011" .... seems a bit obscure to me and I didn't find any info in the Helpfile.

Thanks for your help in advance.

Edited April 26, 2022 by julmou

[Michele Oliosi]

Hi,

The $01 is due to a bug, the correct text should indicate something along the lines of: "increase according to global irradiance on the plane of array".
Basically, it means that the temperature will increase according (proportionally to) to the irradiance on your field, i.e. the power generated. The value to be inserted is the increase in degrees per 1000 W/m^2 of irradiance.

The question of outdoors or indoors is really a question of temperature control. In this case the inverters are probably subject to the ambient temperature, so ambient temperature / ambient temperature with shift are both reasonable choices.

[julmou]

Thank you so much Michele, this is clear for me now.

Just one last question to be sure to understand how it works, regarding the "Increase Acc to Glob Inc, $01" parameter (Temperature increase according to incident global irradiation)

It seems the standard value by default from the software is 25°C. So just to make sure, if I leave the "Base temperature" value at 25°C (i.e. it is 25°C in the room) and the increase also at 25°C, does this mean if I have 1000 W/m2 irradiance outside, the room temperature will be at 50°C?

I mean, is it 25°C base temperature when I have zero irradiance and it only goes up from there? (that could make sense, that would mean 25°C when the inverter is not working basically, and then it goes only up from there with every added irradiance).

Thank you in advance for enlightening me.

What if the inverter room is cooled and the temperature always stays at a constant value, do I just put the increase at 0 and the "Base temp." as the controlled temp?

[Michele Oliosi]

Yes and yes.

If you leave 25° & 25°/1000W you will get 50° at 1000W : 25° is the base temperature.

If the inverter is cooled efficiently then yes you can put 0°/1000W as the proportional increase.

[Omama Zaheen]

@Michele Oliosi

Your above responses are very much helpful. However, I need further clarification on "External ambient temperature with Shift". What does this shift means?

For instance if my external "Maximum" ambient is 40degree centigrade in Summers, what should be the Shift?

[Michele Oliosi]

The option "external ambient temperature with shift", allows to define that the inverter temperature will follow the ambient temperature, plus or minus a constant value in degrees that is defined as the "Temperature increase".

For example if you define a temperature increase of 5°C, and at a given time the ambient temperature is 38°C, then at that time in the simulation the inverter temperature will be 43°C.

[Omama Zaheen]

@Michele Oliosi Which means in the highlighted box I just have to enter the temp increase i.e., 5°C? and PV syst will add this 5°C while running simulations? 
Can you please explain the significance of using this feature in the simulation, for my better understanding. 

Edited May 2, 2023 by Omama Zaheen

[Michele Oliosi]

Yes that is correct. For example if your inverter tends to heat up, you can set a few degrees to indicate that it is warmer than the ambient temperature.

[mohaned]

Hello, regarding the temperature shift, what bases should i consider for this, does it depend on inverter installation method (ex. directly in field, under canopy, in Skid, etc.), do I get this value from the manufacturers, and does PVsyst have any recommendations for values or methodology to consider?

[Linda Thoren]

Hello,

PVsyst does not have any default numbers or recommendations and regarding the temperature shift. The temperature shift can depend on various factors such as characteristics of the inverter, your installation method and site.