On the Reliability of Transformerless Photovoltaic DC/AC Converters Based on Mission Profile

Photovoltaic systems are a technology for the generation of electrical energy that is constantly increasing thanks to current technological advances and that contributes to sustainable development. The main stages of photovoltaic systems are the conversion stage, using an inverter, and filtering. These systems may be considered as a mature and growing technology; however, regarding its reliability, there exists some uncertainties, and they are related to the operation, incidents, and its potential failures, due to the number of elements, the environment, and the operating nominal values. For this reason, this article presents a comparative analysis of the reliability of single-phase transformerless photovoltaic inverters used to inject active power into the grid. This evaluation is carried out under the same design specifications for all the inverters analyzed; the study is made using a mission profile considering the IEC TR 62380 standard, where the events and environmental operating conditions are defined, and numerical simulations. This work is aimed at providing suggestions to improve the quality of the photovoltaic system also considering reliability.