Optimization of an Electronic-Throttle-Control Actuator for Gasoline-Direct-Injection Engines

An electronic throttle actuator with a faster response time and reduced peak current was aimed for the DI-G engine. An qualitative analysis of the drivetrain of the throttle actuator is performed. It was found that to obtain faster response, inertia, motor inductance, and motor resistance need to be reduced, while the reduction gear ratio has an optimal value. On the other hand, to reduce the peak current, motor inductance, motor resistance and the reduction gear ratio must be increased. Based on this analysis, a more detailed numerical calculation is done and design parameters are optimized. An actuator with optimized parameters is prototyped and showed 20% faster response time and 50% lower peak current.