Harmonic currents generated by photovoltaic inverters

Does a PV inverter have a harmonic impact on distribution systems?

This paper proposes an analytical harmonic model of PV inverters to assess its harmonic impacts on the distribution systems. The model is also verified by both simulation and laboratory experimental results. The proposed model indicates that the PV inverter has both harmonic source characteristic and harmonic impedance characteristic.

Do photovoltaic inverters cause harmonic distortion?

The increasing penetration of photovoltaic (PV) systems, consisting of PV panel and PV inverter, may introduce power quality issues to the distribution power system. One critical concern is the harmonic distortion. This paper proposes an analytical harmonic model of PV inverters to assess its harmonic impacts on the distribution systems.

Does a PV inverter have a harmonic source and impedance characteristic?

The proposed model indicates that the PV inverter has both harmonic source characteristic and harmonic impedance characteristic. Furthermore, the harmonic emission of PV inverters is affected by two grid operating conditions, namely the grid impedance and background harmonic voltage.

Why does PV inverter output voltage contain high order harmonics?

According to the previous analysis, the increase of the PV inverter output power may cause PV output voltage to contain high order harmonics under the weak grid, which are mainly distributed near the resonance peak of output filter LCL of PV inverter.

How a PV Grid connected inverter generates output harmonics?

The output harmonics of the PV grid-connected inverter are generated under the action of grid voltage harmonics, resulting in corresponding harmonics of its output current. The fundamental reason is that the output harmonics of the inverter are generated by the excitation of harmonic voltage source.

How a harmonic current is produced by a PV or wind plant?

Harmonic currents produced by the PV or Wind plants depends on the type of inverter/converter technology used for DC/AC or AC/DC conversion and its control strategy. The output current is also linked to the harmonics of the voltage at the POC, which depends on the contribution of all the generations and loads connected to the network.