An open-source - community built micro-inverter

Manifesto 

The project goal are : 

  • Having the first open source PV micro-inverter
  • Finally a design easy to repair that is no longer a black box
  • Redeem your data sovereignty, you will no longer depend on a proprietary cloud to follow your solar production and consumption. 

Open, for everyone, forever

  • This project is propulsed by its community. 
  • The collective work generated is meant to remain open. 
  • Design files are made with open source software - Namely kiCAD.
  • Mechanical interfaces and components are modeled using FreeCAD.
  • Simulation files use ngSpice.

In that sense, the owntech foundation aims at protecting this technical common.

Specifications

This section is inspired from OpenMi.

Comparison of micro-inverters with rated output power between 350VA and 400VA is given in the project github repository.


uVerter Target specifications

CategoryRequirementNotes
Grid230VAC - 50HzDesigned for EU style grids
Grid complianceGrid-code compliantExact certification scope depends on country/standard
Rated apparent power450VASoftware-limited power cap supported
Input DC operation range16V - 58VPV module operating window
Recommended PV input power350W - 550WDepends on module and thermal conditions
Efficiency>95%Target nominal conditions
Power factor≈ 1Near-unity PF at rated power
THD<5%Total harmonic distortion at rated conditions
IsolationGalvanic isolationElectrical isolation between PV and grid
Operating temperature-40 °C to +60 °CDerating may apply
RepairabilityNo invasive pottingDesigned to be serviceable and inspectable
ConnectivityWi-FiLocal-first monitoring (no proprietary cloud required)

Standards and directives

  • IEC 62109: Safety requirements for photovoltaic inverters.
  • IEC 61727: Requirements for photovoltaic (PV) systems to interface with the utility grid.
  • IEC 62116: Test procedure for islanding prevention measures for utility-interconnected photovoltaic inverters.
  • EN 50438: Requirements for the connection of micro-generators in parallel with public low-voltage distribution networks.
  • EN 50549: Requirements for generating plants to be connected in parallel with distribution networks (superseeds DIN VDE 0126)

Licence 

This project is licenced under **CERN-OHL-V2-S** open source hardware licence. Licence file can be found under `License/cern-ohl-v2-s`.