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The Nuna 6 is a solar racing vehicle that solely relies on solar energy from the sun. Every year, the team seeks ways to improve the performance of their car. One way to improve the performance is to maximize the power output of the solar panels on top of the car. Maximizing the power output can be done with a 'Maximum Power Point Tracker'. The aim of this thesis was to develop an improved, distributed 'Maximum Power Point Tracking'-system which optimizes the power efficiency of the solar panel array of the Nuna 6 solar racing vehicle. To prove that the proposed distributed topology is more power effificient when compared to a central tracking topology, simulations of the total Nuna 6 electrical system were performed. Based on the simulation results, together with Nuna 6 specifications, a DC-DC boost converter was designed. Validation of the design was done by simulation with the Nuna 6 model. After validation, a breadboard proof-of-concept was built. The proof-of-concept was successfully tested and compared with earlier simulations. The system design process was evaluated and recommendations for further study and future real-life implementations were formulated. The simulation results prove that the proposed distributed tracking system is as much as 40% more efficient in large insolation differences and 10% in small insolation differences. The system excels when insolation differs, however it is slightly less efficient when used with equal insolation on every panel. The developed proof of concept demonstrates a functioning maximum power point tracker and DC-DC boost converter. The power efficiency of the boost converter was found to be between 95:8% and 98:5%, with an efficiency of 97:1% for the rated input power of 200W.

Currently, the Nuon Solar Team is building their new solar car, which makes use of solar panels. Solar panels have a Maximum Power Point (MPP), which, when operated at that point, ensures the maximum available power is obtained from them. In this thesis, different options were explored to solve the problem of tracking the MPP of a solar panel. The focus of this thesis was the software part of tracking the MPP and the goal of this thesis was to implement the most efficient algorithm that works in fast changing levels of irradiance and when thesolar panels are partially shaded. In order to realize this goal, we first did a literature survey to learn about the available algorithms and their respective advantages and disadvantages. Subsequently, we chose the algorithms which had potential and we could realistically implement. Those algorithms were P&O, In ond and their adaptive variants. We simulated those algorithms for their efficiencies in Simulink and implemented them onto a microcontroller. Lastly, we made an experimental setup and measured the algorithms for their efficiencies. The results showed that based on the simulations, the adaptive InCond algorithm is the most efficient algorithm, also in fast changing levels of irradiance. As the simulation did not simulate partially shaded solar panels, we can not make any conclusions about the performance of the different algorithms in that case. In the experimental setup, we verified that the controller and all implemented algorithms worked correctly. However, we were not able to verify all the simulation results, as we could only only test the sudden shading condition. The MPPT was able to reliably track the MPP of a solar panel, depending on what algorithm was used. Some algorithms were more susceptible to noise than others, and eventually we concluded that the adaptive P&O algorithm performed best in the experimental setup, because it is least susceptible to noise and has the advantages of an adaptive algorithm. We did not measure the efficiency of the MPPT. However, based on the simulations and the measured efficiencies of the other subsystems of the MPPT, we are confident that we succeeded in designing and implementing an MPPT algorithm with an efficiency of at least 95%.

The world is rapidly moving towards a greener future, a mainstay of which is solar energy. Hence, maximum power point trackers, or MPPTs for short, are an indispensable component, since these devices provide one with the capability to fully maximize the achievable power from solar cells in a system. A symbol of the greener world that is evolving around us is the biannual World Solar Challenge, where state-of-the-art solar powered cars race against one another through the deserts of Australia. This thesis forms the link between these two elements: to design an MPPT optimally suited towards the requirements of the Nuna Solar Car. Commercially available MPPTs are not particularly well suited for the specific demands of such a bleeding edge race. They are mostly designed for high power or low voltage systems. The MPPT designed during this thesis is optimized for high efficiency and other requests stated by the Nuon Solar Team members. The design of the MPPT has been split into several parts. This thesis is focused on the converter within the MPPT. It presents the result of research, design exploration, simulation and testing. The results obtained with the prototype that has been built show the designs correctness and conformance to the requirements, with an efficiency of up to 98,5%.