Step 3 Maximum MPPT Voltage

Concept

VPmax STC Voltage at maximum power of PV module at STC/Maximum power voltage / Voltage at Pmax, VPmax STC/Vmpp/Vmp/Vm (V)

VPmax max Maximum voltage at maximum power of PV module (V)

βVpmax Temperature coefficient for voltage at maximum power (% °C⁻¹ or % K⁻¹). 

• In most cases, if βVpmax is not given, then assume βVpmax = temperature coefficient of Pmax, γPmax.

Tmod min Lowest module temperature (°C)

• Assume 20 °C if not given

TSTC Module temperature at STC (°C), 25 °C

3.2 Calculate Ns max mppt

Ns max mppt Maximum number of PV modules in series based on maximum voltage at maximum power (units)

Vmax mppt inv Maximum MPPT input voltage of the inverter (V). 

• Maximum power point of the PV array can't be tracked if inverter input voltage more than this value.

• Select "MPP voltage range" for Vmax mppt inv value

Ns max mppt = round down [ 500/30.916 ] = round down [16.17] = 16 units of PV modules