Filter and sort
What is a three-phase grid-tied inverter?
A three-phase grid-tied inverter converts the DC energy from photovoltaic panels into 400 V AC distributed across three phases and synchronized with the grid. It is the foundation of three-phase self-consumption in residences with 3 phases, businesses, SMEs, and industrial buildings, allowing real-time consumption and (according to regulations) exporting surplus or limiting export.
When to choose three-phase
- When your supply is 3 × 230/400 V and you need balanced load distribution.
- Projects with higher power (from ~3–100+ kW) or with multiple roofs/strings.
- Installations requiring export control, granular monitoring, and robust communications.
Key selection aspects
- Nominal power (kW): match to PV peak power, contract, and consumption curve.
- Number of MPPT: 2–10+ trackers to optimize different orientations and string lengths.
- Electrical ranges: check Voc/Vmp/Isc per MPPT and current per input.
- Functions: export limitation with meter/CT, anti-islanding protection, SPD DC/AC, integrated disconnection.
- Communications: RS485/CAN, Ethernet/Wi-Fi, portal/app for monitoring and O&M.
- IP rating: many models are IP65 for outdoor use.
Diagram and compatibilities
| PV input | Strings in series/parallel within the range of each MPPT |
| AC output | Three-phase 400 V (3 phases + N), anti-islanding according to standard |
| Export management | Bidirectional meter or CT for zero export/limitation |
| Protections | DC/AC, SPD type II, disconnection and relays |
| Monitoring | Portal/app, event log, APIs (depending on manufacturer) |
Three-phase string or microinverters?
- Three-phase string: better €/kW ratio and centralized management; ideal for uniform roofs.
- Microinverters: module-level optimization for partial shading or highly varied orientations; facilitate panel-by-panel expansion.
Do you need storage?
To add batteries and three-phase backup, consider three-phase hybrid inverters with HV or LV 48 V batteries according to compatibility.
Good design practices
- Calculate Voc at minimum temperature to avoid exceeding the limit per MPPT.
- Balance strings by modules and orientation; use SPD and disconnectors in DC and AC.
- Configure and test the export limiter with meter/CT before commissioning.
- Plan a ventilated, accessible location with optimized cable runs.
With the right three-phase grid-tied inverter you will achieve efficiency, reliability, and control of self-consumption in higher power installations. If your supply is single-phase, see single-phase; if you need batteries and back-up, consider three-phase hybrids.
