Hi everyone, I’m Owen from the York Formula Student team. We are a relatively new team competing in the FSUK competition under the EV category. Last year, AISLER very kindly gave us a sponsorship for PCB manufacturing. One of the first boards we ordered through the sponsorship was our precharge board, of which you can find the project files on our GitHub.
The precharge board is one of the most important boards in the car as it has the critical function of charging the inverter’s large capacitance in a slow and controlled manner, as well as controlling the main accumulator isolation relays (AIRs) of the car. The circuit achieves this using a dedicated pulse-rated precharge resistor and relay combination. To ensure proper operation, a microcontroller, through the help of two AMC1351 isolated amplifier ICs, measures the voltage at both sides of the precharge resistor (effectively the voltage at the battery and inverter) and compares it to the expected voltage at regular intervals. The board also features CAN communication for start control and telemetry.
The boards received from AISLER are very high quality. We designed them in KiCad, which works great with AISLER’s push plugin and makes it very easy to upload new layouts, as well as modify existing ones seamlessly.
