In order to achieve the stability of the internal combustion bolt wrench controller, this paper found that there was a surge between the gasoline generator and the controller. And in practical applications, the circuit surge interference will lead to frequent access control device into the protection state, which seriously affected the use of internal combustion bolt wrench. In view of the above problems, this paper designs two kinds of power surge soft start suppression circuits by using nonlinear components such as diodes, power resistors and TVS tubes. The simulation results show that the circuit can effectively suppress the surge and provide a stable working power for the internal combustion bolt wrench by circuit simulation and the combination of the internal combustion bolt wrench.