Photovoltaic Impedance Measurement based on Interleaved Boost Converter

This paper describes a photovoltaic (PV) impedance measurement method based on input ripple current interleaved boost converter (IBC). The IBC is used to boost the voltage output while controlling the PV to operate in the maximum power point tracking (MPPT). The input ripple current is adjusted based on the level of interleaved in IBC for the PV impedance measurement. The response of the PV terminal voltage is measured, and the PV internal impedance is obtained based on the input ripple current and the measured voltage at the PV terminal. At the same time, the IBC is used to boost the voltage output, operate in MPPT, and substantially reduce the losses. PSIM simulation is used for the simulation and three series PV modules are utilized for the experiment to validate the proposed impedance measurement.