Testing and Validation of LV MPPT Center Unit (MCU) (Sono LV MCU)

This report presents the main findings of the tests to which the MPPT Control Unit (in short MCU) was subjected. The specific tests were conducted in the frame of ERIGrid 2.0 under the Transnational Access activity project no. 159-“Sono LV-MCU”. During the project selected units were subjected to a number of tests including electrical, thermal and MPPT accuracy ones. This report presents the key findings for each performed test alongside with specific information regarding the preparation of some tests. The complete set of tests is intended as a prestandardization validation of the MCU in order to provide useful information to the manufacturer towards streamlining the design and meeting the required standards. All in all, the MCU proved to be a very robust and reliable unit that endures a significant amount of stress tests with minimum potential issues to be considered for future improvements. 

In this context, the first part of this report presents some general information regarding this project including the scope and objectives. The main motivation presented in the specific section is the testing of the MCU according to standardized procedures in order to investigate the readiness level of the unit not only for certification but also for mass production.  

The second part focuses on the state-of-the-art information related to this project, which is in line with the relevant application text for this project. Based on that, the said MCU shows some advantages compared to other off-the-shelf MPPT solutions, including better performance under dynamic conditions and conformance with automotive regulations and standards. 

The third part presents an overview of the conducted tests, the procedures and standards on which these tests were based and some key results. The tests conducted during the project include electrical and thermal evaluation and are mostly based on the ISO16750-2, and ISO16750-4 standards as well as specific testing protocols by Sono Motors GmbH.  

Some more detailed results are presented in the fourth part of this document together with some discussion and conclusions. One particular part of the results regards the lifetime test and the fact that the MCU presents at least 5 years of lifetime based on the conducted experiments.

Finally, the fifth part focuses on some suggestions for future work on the subject, including the potential extension of the lifetime tests to 10 years for a number of MCUs.