dawiddebinski avatar image
dawiddebinski asked

Microgrid / 9x Quattro II 48/15000

I kindly ask for your help. My question is about the possibility and behavior of a potential three-phase microgrid based on Victron. I mean 9x Quattro II 48 V / 15 kVA (3 for each of the 3 phases) First I will briefly describe the layout:

  • AC IN1: generator set with S=150 kVA
  • AC IN2: a power grid with a contract limit of consumption of a maximum of 100 kW and sending to the grid of a maximum of 50 kW
  • AC OUT1: load group I (power supply to the building, about 15 kW); load group II (power supply to vehicle chargers 6x 11 kW).
  • AC OUT2: vehicle chargers 6x 11 kW.
  • There are 48 kWp of photovoltaic installations available, with an option to expand on the AC-output inverter for an additional 50 kWp (I plan as AC-Coupling).
  • The microgrid also have energy storage for 48 V, about 200-250 kWh.


  1. You can't give more than 50 kW to the electricity grid. I would like to give away only surplus from photovoltaic installations. To the grid can not give the energy storage or genset (AC IN1). If the power grid (AC IN2) fails, does Victron have an anti-islanding protection and will not allow voltage to be applied to the broken grid?
  2. Will it be advantageous in terms of maximizing sources to connect PV installations (between 50 kW and 100 kW) to AC OUT1 to supply critical loads (80 kW, AC Coupling), or is it better to use PV in Parallel with the input of the power grid (AC IN2). It seems to me that by connecting the PV to AC IN2 I am limiting my sources (max 100 A on AC IN), and yes I can use the grid and source on AC OUT1 (direct demand supply).
  3. What can be the maximum power of attached sources to AC OUT1 with a three-phase system (3x 3x Quattro II 48/15000)? What if the PV connected to AC OUT1 will generate 90 kWp, the loads in AC OUT1 will consume 20 kW, and the loads in AC OUT2 will consume 10 kW (assuming charged energy storage). This will leave 60 kWp to be used. This will be routed from AC OUT1 as surplus to the power grid (taking into account that we can send up to 50 kW, so 10 kWp would be unused).
  4. What is the maximum power of loads connected in such a system 9x Quattro II in AC OUT2? I am currently thinking of using 66 kW.
  5. Does the Quattro II have double power conversion?
  6. What if the energy storage is discharged, too low voltage on the batteries starts the generator, the loads from AC OUT1 and OUT2 are 130 kW, from the power grid the system draws 100 kW, the genset is switched on additionally. Will it generate as much power as is missing from the balance? It is not permissible to send back energy from the genset to the power grid.

ac out 2ac couplingfeed-in limitQuattro-II
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1 Answer
Alexandra avatar image
Alexandra answered ·

I am going to start with - this is a design question and technically breaks the community guidlines.

So start advice is - this is not a toy system go and speak to a distributor. They are equipped to answer your questions and you will need their back up support. You are asking base questions so i am going to assume you have no experience, which means you will likely be largely unsupported if you dont work with a distributor.

That being said....

Q1. Yes you can limit feedback and control when it happens. Yes there is anti islanding see the product page and certificates. (Related resources page)

Q2. Sizing of PV depends and installation position depends on if you are intending to go above the AC couling rule 1:1. And if you need the use of the microgrid in case of power faliure, since AC PV needs AC to produce.

Q3. Will depend on how good your parallel set up actually is and temperature derating. In theory you are 3x 15kva x PF. inverting at 25°C. AC2 since it is switched is lower.

Big question also maybe brek it down a bit. Feels like i am ina board meeting.

Look at victrons ESS manual.

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Related Resources

Quattro II Product page

Quattro II Online Manual

Pre-RMA bench test instructions.

Additional resources still need to be added for this topic

AC-coupling and the Factor 1.0 rule

AC-coupled PV with Fronius PV Inverters

Additional resources still need to be added for this topic

Additional resources still need to be added for this topic