Hello Victron Team,
Can you explain me what exactly is the "BoostFactor"?
Thank you
Kind regards
Pablo
asked
Multiplus BoostFactor
Hi Botnic, please use the help function in VEConfigure. Its the go to place for all these kind of questions.
Hi, so a quick case study question.
We have a system with Quattro 8k/230V with input current limit set on 60A and Power Assist Boost ratio is set to 2.0.
How let's assume we have an abrupt load request - Quattro assumes 2.0*60A current (according to the manual). And at that moment what does it exactly do?
1. Would it prepare those 120A from the batteries? If such, does it ease the input for a few cycles and inverts power from the battery?
2. Would it keep 60A from the input and add 60A from the batteries?
The below chart shows currents active and reactive and THD (sorry for LQ graph, hope it's readable) on the input of Quattro (actually output from grid inverter). It looks like when power assist kicks in, it eases the input for a "second", adds power from DC and brings input current to a previous state.
It's worth mentioning it's not happening always, but at times, which is strange.
Hi, I have some questions extra. The help in VE Configure dosen´t seem to be very clear for me.
When Multi switches to sassist mode, will the inverter provide always current = AC IN current limit * boost factor ?
Than, this provided current is still the same and Multi will drive AC IN current according to the need? Or the current provided by inverter wil be regulated after some time according to need to keep AC IN current on maximal limit?
If AC IN current limit * boost factor is higher than a maximal power of inverter, than Multi trimms maximal provided power or it falls to allarm and mistake?
I can use assistant "input current limit control" to drive AC IN limit by AUX. Than Multi counts the assist current from AC IN limit set on a "General" card of a VE Config, or from limit driven by AUX?
Thank you for your reply.
Martin
After some tests I´m able to reply myself. I did not measured exactly, only watched what Multi is doing...
When Multi switches to sassist mode, will the inverter provide always current = AC IN current limit * boost factor ?
Yes, but often it is not possible, so it just gives maximal possible current.
Than, this provided current is still the same and Multi will drive AC IN current according to the need?
No.
Or the current provided by inverter wil be regulated after some time according to need to keep AC IN current on maximal limit?
Yes, after cca 0,5s inverter regulates it´s power to normal power assist function.
If AC IN current limit * boost factor is higher than a maximal power of inverter, than Multi trimms maximal provided power or it falls to allarm and mistake?
I still don´t know, but moment using boost factor is so short, so i thing inverter never falls to mistake. If needed power is too big, it probably falls to mistake later anyway...
I can use assistant "input current limit control" to drive AC IN limit by AUX. Than Multi counts the assist current from AC IN limit set on a "General" card of a VE Config, or from limit driven by AUX?
From currently set limit - given by assistant at this case.
Thank you for your reply.
Oh, that´s a pleasure!
Martin
I think this is related to your other question.
However, it is normally recommended to be at 2.0. It is the peak power that the inverter will provide when shore current is no enough.
So, for normal operation, it is recommended to be set to 2.0. Does this mean that if my AC current limit is set to 9 amps that it would provide up to 18 amps?
Also, What scenarios could arise where this value would be better set to another value either higher or lower?
Boost Power Ratio to be expected, if the inverter has to assist. WKirby was faster. :o)
If you set this factor too high, you will have Overvoltage Peaks, when Power Assist kicks in.
If you set this factor too low, Power Assist might not work properly.
Thanks, Marcus. I am trying to learn, and this is the most helpful statement yet, but ...
What are the consequences of the over-voltage peaks? Is this a power quality problem or will it lead to shut down, or dropping the AC input? And what exactly is low? Less than 1.0? How will we recognise that it is not working properly? I am ready to learn if anyone can help me here.
Nowhere is this clearly explained and in some places we are told we cannot understand it so leave it alone, which is fine by me except I am curious. If it is set at 2.0 does that mean it will come in with twice the input current limit? Or it will add the same current again, to double the combined current (which seems more likely to be appropriate)? And why would we want to set it to 1.0 for example? And would it still work if set to lower or higher values, and what is the downside?
Thanks.
