Solar - Photovoltaic array analysis

Array Performance in the Field

There is no better method of predicting photovoltaic (PV) array performance than exposing it to real-life conditions in the field. Although laboratory tests can accurately determine PV cell characteristics, real-time monitoring of a photovoltaic array in the field can boost confidence in product reliability and overall performance.

The many effects of a real-world environment, such as change in irradiance, temperature, and other external factors, can make monitoring and analysis of PV installations a daunting task for those accustomed to a controlled environment.

A fast, accurate, and carefully synchronized test approach is required to obtain meaningful data in ever-changing conditions like those described above. By obtaining Voltage (V) and Current (I) readings at different PV loading levels, a separate I-V curve can be generated for each the array, the string (series of panels), and the individual panel, required for adequate characterization in the field.

Measurements collected from I-V data can also be used to calculate the array’s Maximum Power Point (MPP) at different instances throughout the day, providing a key indicator of the installation’s performance.

A proposed test/monitoring system for field applications is described and can be read by clicking the link below.

Testing Array Performance

Software

New I-V Characterization software

The Chroma I-V Characterization soft panel provides users with valuable information about their photovoltaic cells or panels. The application can generate I-V curves and report key elements such as Isc, Voc, Pmp, Vmp, Imp, Fill Factor, Efficiency, Rs, and Rsh. Tab delimited text reports for both summary and I-V data points are made available and can be used by other applications for post-processing. Various hardware and software configuration options allow users to adapt and customize the soft panel to best fit their PV cell/panel. This soft panel makes use of the internal measurement and current range capabilities of Chroma’s 63600 series DC Loads, ensuring fast and accurate PV characterizing. These softpanels are now available.