Solar Cell Impedance Measurement: Leveraging Test Equipment Modernization to Obtain Equivalent Circuit Model of Multijunction Solar Cells

Designing a solar array regulator requires in-depth knowledge of the solar array itself. Whilst the static response tends to be at the core of the design, its dynamic response also has to be taken into account. In order to do so, the capacitance, and more broadly speaking the impedance, of the solar array must be measured, or evaluated. The measurement of a solar cell impedance is a complex endeavor as the factors influencing the dynamic behavior of a solar cell are varied. Extracting the impedance of a given solar cell requires a specific and non trivial test bench. Leveraging the recent advances in test equipment, the objective of the test setup described herein is to provide a direct method of impedance measured for solar cells under varied conditions to extract the electrical equivalent circuit and parameters. Varied methods will be presented and discussed as well as the rationale behind the chosen test setup.