Developing a New Field Test System for Solar Panels

Abstract

The Photovoltaic Materials and Devices group at the Technical University of Delft requires a system to measure the outdoor characteristics of photovoltaic modules of different sizes. To perform this task, the Open-Source Photovoltaic Electrical Tool is a viable baseline solution. The device struggles to dissipate enough power to make measurements for the high-power photovoltaic modules. In this paper, a method for dissipating eight hundred watts of power is proposed that can be implemented without altering the Open-Source Photovoltaic Electrical Tool. This is done using a scalable, parallel linear Metal-Oxide-Semiconductor Field-effect transistor load extension. A printed circuit board has been designed using active components to match a reference signal with a shunt voltage to maintain a steady current and prevent thermal runaway. On each board, an I2C-based temperature monitoring system is used to shut down power when a thermal limit is reached. After testing, the matching boards prevented thermal runaway and kept the current steady across all parallel load devices, even under artificially heated conditions. Due to cumulative voltage drops across the shared ground path of the daisy-chain connector, slight differences in the currents were observed. This will make the first board carry more current than the last, a potential solution for this is proposed. Additionally, thermal testing demonstrated that using an all-in-one cooler, a single load device could safely dissipate one hundred and twenty watts continuously. Placing it all together, the Open-source Photovoltaic Electrical Tool, together with the active matching boards and an All-In-One cooler, is able to measure the characteristics of a large range of Photovoltaic modules that the Photovoltaic Materials and Devices group and students aim to test.