Throttle-control algorithm for improving engine response based on air-intake model and throttle-response model

An electric-throttle-control actuator (ETC) is a device for control of the air mass flow to an engine cylinder. As adaptive-cruise-control and direct-fuel-injection systems become popular, the market of ETC has become larger. The ETC is controlled so that the engine torque follows the target value. Between the change of the control signal to the ETC and the engine-torque response, two delays exist-the delay in the throttle response and manifold filling. These delays must be compensated to improve the engine response. In this paper, a throttle-control algorithm for improving engine response is proposed. This algorithm compensates these two delays based on the response model. The response of the manifold pressure was experimented in two cases, when the ETC was controlled by a step input and when the throttle was controlled by the developed algorithm. The experimental results show that the rise time of the manifold pressure response decreased to one-tenth by the developed algorithm. Because the engine torque is proportional to the manifold pressure, it can be concluded that the torque response improved by compensating the two delay factors.