PV Inverters

DERSim emulates single-phase, split-phase, and three-phase photovoltaic inverters with full SunSpec 700-series compliance. The DC-side I-V curve is sampled each tick from the array's irradiance and cell temperature, so MPPT-tracking inverters exercise the curve realistically — including partial-shading scenarios where the curve develops a secondary maximum.

Starting a PV inverter

Three phase variants are bundled. Pick the matching one with -d / --device_type:

./sim --device_type PV-3Phase     # three-phase, alias 'PV'
./sim --device_type PV-2Phase     # split-phase (residential US)
./sim --device_type PV-1Phase     # single-phase (residential EU / RoW)

The default sizing is a 10 kW array; nameplate ratings come from the bundled profile and can be overridden via a JSON nameplate file (-f). See Simulation Inputs — JSON nameplate format for the full point-by-point reference.

DC-side physics

The DC-side model is irradiance-driven:

  • I-V curve — EN50530-style curve parameterised by 714.Prt[0].DCW (Pmp at standard conditions) and 714.Prt[0].DCV (Vmp). The curve is sampled each tick from the active irradiance + cell temperature.
  • MPP tracking — the simulator's internal inverter walks the curve to find Pmp; external MPPT-aware test harnesses see a realistic operating point that responds to irradiance changes on the DC IV curve view.
  • Cell temperature — first-order thermal model. Rises above ambient with sustained MPP operation, reduces open-circuit voltage at high temperature.
  • Irradiance — driven from the bundled irradiance.csv or any custom CSV via --dc_profile (see Simulation Inputs — DC source profile).

Profile variants

The bundled 10kW-3Phase.json profile sets a residential array. A 500kW-3Phase.json profile is also bundled for commercial / utility-scale tests. Either can be selected via -f:

./sim -f profiles/10kW-3Phase.json
./sim -f profiles/500kW-3Phase.json

For custom nameplates (different rated kW, different SunSpec register set, different initial energy registers), copy a bundled profile and modify it — see Simulation Inputs — JSON nameplate format.

SunSpec model exposure

PV inverters populate the same general DER SunSpec model set every other device type uses:

Model Purpose Notes
1 Common Manufacturer, model, serial number
701 Nameplate + live AC measurements W, Var, VA, V, A, Hz, PF, plus energy registers
702 Settings + ratings WMax, VAMax, VAR limits
703 Enter Service Service state, voltage / frequency thresholds
704 Fixed Power Factor PF setpoint when fixed-PF mode is active
705 Volt-Var Curve points
706 Volt-Watt Curve points
711 Frequency-Droop Deadband + slope
712 Watt-Var Curve points
714 DC-side input One port with PrtTyp = 0 (PV) — DC voltage, current, power, energy

The DC-side I-V curve is available as JSON via /api/dersim/dc-iv for programmatic MPPT-validation harnesses; see DC I-V curve.

Grid-support modes

Every grid-support mode that applies to a generic DER applies to the PV inverter without modification — see the Power Simulation chapters for the individual mode references:

Dashboard view

The dashboard's overview page renders the live AC delivery, PV operating point, and IV curve all on one page. The Analytics view adds time-series plotting across a configurable window — useful for replaying an irradiance event and seeing how the inverter responded.

Cross-references