Facility - PV Test
The PV test unit consists of 4 stands; a fixed stand (Stand 1) that is oriented toward South and with variable tilt angle (25° to 75°). The structure has two frames that can be tilted separately so that different inclinations can be tested simultaneously primarily when the sun is at midday. The stand can host up to six PV modules and is fully instrumented with an in-plane pyranometer, reference cells for mono, poly and amorphous silicon technologies, PT100 sensors for modules temperature measurements, ambient temperature sensor and sonic anemometer.
The second stand is a sun tracker (Stand 2) that can host up to two PV modules of large size. Also the sun tracker is equipped with sonic anemometer, in-plane pyranometer, reference cells and PT100 for PV modules temperature measurements.
The Stand 3 is shaped as a big box on top of which flexible thin film modules can be arranged in horizontal position or in curved position with various curvatures. This stand has been conceived to evaluate performances of PV modules integrated in buldings or roofings with particular shapes.
The last acquisition is Stand 4 expecially designed to make comparative tests of PV modules in vertical and horizontal position also varying the stand orientation.
The PV modules are continuously monitored using an electronic unit that can keep each device at its Maximum Power Point (MPP). In this way the device is stressed as if it operates in real production conditions. The instrument is called MPPT3000 and is developed and provided by ISAAC-SUPSI of Lugano. Maximum current and voltage are measured every minute together with all the environmental parameters; every 10 minutes a complete I-V curve is retrieved for each PV module. Data are collected by a Campbell Scientific CR1000 data logger via RS485. All the ESTER units are connected to the web and data are downloaded every 30 minutes in a database of a dedicated server.