Working with the PCB's
The TU Delft Solar Boat Team designs and builds a boat that sails on hydrofoils, powered by solar energy. Our goal is to win the Solar Sport One competition and to show the maritime industry that a lot can be achieved with solar energy. However, as a student team, we also have the goal of learning and pushing the limits to reach maximum efficiency, since we have a lot to win and almost nothing to lose. Therefore, we try to design most of the components ourselves, to optimize them to our use and gain that extra impulse in efficiency that will make the difference to win the race. In the electronics department, we focus on building a reliable system that can deliver the energy from the solar panels to where it is needed in the boat in the most efficient way.
We design our PCBs and they are manufactured by our sponsor Eurocircuits. Later, we
receive the boards and the components and in most of the cases we solder them ourselves. These PCBs are placed in different boxes in the boat, connected through the cable tree in a smart way so that they can always be directly replaced if needed during the competition. The whole system is composed by the following PCBs:
- The 24V converter is placed in the energy box and connected to the battery. It is a buck converter that lowers the battery voltage to 24V to feed most of the systems in the boat.
- The Energy Management System (EMS) is placed in the energy box, and it is one of the most complex systems in the boat. It receives the energy from the battery and 24V and it is connected to almost all other subsystems. The function of the EMS is to deliver the energy to where it is needed.
- The Battery Management System (BMS) is directly connected to the EMS and the battery. It is a passive system that dissipates energy from the battery in resistors to adjust the voltage so all battery cells are at the same level.
- The Maximum Power Point Trackers (MPPTs) are for the first time this year designed by our team instead of bought from an external company. They have been manufactured and also assembled by Eurocircuits, due to their complexity. They are converters that adjust the working voltage of the solar panels to ensure maximum output. They are placed in an apart box between the solar deck and the battery, and there is one MPPT per array of solar panels, making a total of 11 PCBs.
- The Dashboard is placed next to the pilot and serves as the interface between him and the boat. Through the dashboard, the pilot can start the boat, activate the solar deck and start the bilge pump and the cooling.
- There are also two Height Control PCBs, one per strut. They receive the information from the pilot when the flying is activated, and they contain the program that states the angle the wings have to rotate to maintain the flying height desired.
- The Steering system also contains one PCB, placed directly in the steer, which translates the input of the pilot and sends it to the CAN bus. It is also connected to an angle sensor to analyze if the performance of the boat corresponds to the theoretical model.
- The Logger is an apart system that is in charge of storing all the information from the CAN bus into a SD card during testing, for further analysis of the data in order to improve performance.
This makes a total of 8 different PCB designs in the boat and 19 boards divided in the different boxes. Every year, we try to make more systems ourselves instead of buying the commercial option available, which increases our efficiency since the systems are specifically designed for our application. The next system we would consider building could be the motor controller, quite big and complex, so certainly a challenge!