【摘要】 分析了影响汽油发动机怠速稳定性的因素，设计了一个以发动机转速作为反馈信号的怠速控制系统。该系统以ＭＣＳ８０９８ 单片机作为中央控制器，通过步进电机带动旁通气道中的阀门旋转来调节缸内混合气量，以达到稳定怠速转速的目的。台架对比实验验证了所设计的怠速控制系统的有效性。更多还原

【Abstract】 Improvement of idle stability of SI engines is the key factor to raise the idle running quality. In this paper, the disadvantages affecting the stability of idle speed have been analyzed and investigated. Because of the complexity of engine idle process, a closed loop control system for the idle speed has been proposed. In the system, a MCS8098 single chip computer is taken as the controller, engine speed as the feedback signal and a stepper motor as the actuator. The hardware and software of the system, the method to control the stepper motor and the control algorithm of idle speed have been discussed in detail in this paper. To prove the effectiveness of the control system, a comparison of idle speed control processes respectively by the closed loop system and a carburator to control a CA488Q engine was carried out. The results show that with the closed system to control the engine idle speed, the idle running quality is greatly improved and the engine speed fluctuation is remarkably reduced. It proved that the control system is useful and effective for raising engine idle stability.更多还原