Racing car Power Distribution Module

FESB Racing is a group of enthusiastic students dedicated to designing and building Formula Student race cars and MotoStudent race bikes. Goal of our association is to enrich students' knowledge through teamwork and professional work. 

As majority of our vehicles' components are designed in house, it is necessary to ensure that all our systems are properly supplied, monitored and safe from any unusual activities . This is why we decided to design our own Power Distribution Module. Power Distribution Module or PDM is a complex PCB board that replaces both fuses and relays and supplies all our devices in racing car with power. It is, so far, our biggest embedded hardware project.

As already mentioned, PDM supplies voltage to all devices found in racing car. Not all devices operate at same voltage levels, therefore it was necessary to provide different voltage levels that will be needed in vehicle. There are several voltage regulators - buck converters, boost converters and linear converters for each loaded device to ensure required voltage is supplied to the device. With proper application of each we have 24V, 12V, 7V and 5V outputs. This covers all voltage ranges for other devices.

Instead of using numerous fuses and relays, PDM is designed to control all systems with the use of smart switches that act as a replacement for all these fuses and relays. Smart switches measure current in every moment and based on default parameters turns the load ON/OFF. Along with current, PDM also has voltage and temperature monitoring. Biggest advantage of having smart switches is not having to change relays and fuses, but to simply detect problem and to rectify the fault. Major advantage is also self repair during driving. Instead of blown up fuses which would disqulify the car from the competition, PDM simply restarts and allows car to continue racing if the load is still undamaged.

PDM is based around STM32 series of microconntrollers. Default parameters are programmed based on the load's specs and are important part of PDM functioning system. Measured values are compared to these parameters and if fault is present, channel turns OFF. Some of the faults are overcurrent, short circuit, short to VCC, overtemperature, overvoltage, undervoltage. All data is shown on our custom made display with a warning if FLT is present. 

The entire PCB is designed so that it complies with automotive power supply protection. To send and receive data, PDM has integrated CAN and connects to network to communicate with other devices in same network.