Recent Challenges Regarding the Verification of Photovoltaic Inverters Properties and their Compliance with Technical Requirements

Distributed generation by renewable energy sources, is a new phenomenon in recent years and it brings several challenges for electric power system operations. Given that, distributed generators shall be strictly in compliance with relevant standards and technical requirements, to preserve current level of quality and reliability of electric power supply. Therefore, this research is aimed at compliance verification of non-synchronous power generating modules, with any relevant requirements. At the beginning, it provides comprehensive review on this issue including historical development, the current situation in the Czech Republic and relationships between legislation and standards, currently in force. The main contribution of the paper lies in the experiments performed on photovoltaic inverters, which represent the key components of photovoltaic systems and are responsible for fulfilling the imposed operational requirements. The results provide a real-world picture of the current state, in this field. We found that none of the tested inverters fulfilled the requirements to the full extent and therefore, we recommend careful verification of the power generating modules, units or component's ability in this regard, before commissioning.