A high power density inverter, the size of the control board also plays an important role. Designing a small, full-featured, high-performance and reliable main control board is extremely important in high-power density permanent magnet synchronous motor inverter. The hardware platform is simple in design but excellent in performance. The high power density main control board is 85mm long and 60mm wide, and all chips are 125 degrees working temperature. The board has a high-power experiment on a 83kW controller. The results show that the control performance of the main control board is good and reliability.