P-V characteristic curve

The P-V characteristic curve plots the output power of a PV module or string against its operating voltage. One manufacturer FAQ describes the PV curve as the output power of a PV module under different light intensities. It describes the I-V curve as the relationship between output current and output voltage. To get the curve, the string is run at a series of voltages and the current is measured at each one. The result is shown as an I-V curve, and the matching power curve is often drawn with it. Inverters that perform maximum power point tracking look for the voltage operating point that gives the most energy, and they can use this same capability to measure the curve during operation. Some inverters have a diagnostic function that can show the measured data either as an I-V curve or as a P-V curve. Comparing a measured curve with the ideal curve, or with earlier measurements taken in similar conditions, shows deviations that point to array problems at an early stage. This diagnosis suits commissioning, periodic maintenance checks and fault finding.

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• sentence 1: support check: partial - P-V is called a power/voltage curve, but the passages don't explicitly say it plots power against operating voltage of a module or string; u8 describes power under different light intensities. -->