The Fuel Control System and Performance Optimization of a Spark-Ignition LPG Engine

This paper presents an approach to control air fuel ratio of a Liquefied Petroleum Gas (LPG) automotive engine. The optimization of compression ratio is also described in this paper. HC, CO & NOx emissions of LPG engines can be reduced after the application of airfuel ratio control. The control strategy presented in this paper is proved to be appropriate. H infinity control method is used in this engine system because of the robust advantages. The control precision of air fuel ratio is distinctly improved. The software and hardware designs of control system are also described in this paper. H infinity air fuel ratio control and the performance optimization have been developed on a 1.46-liter 4-cylinde spark-ignition LPG engine. The experimental results show that this system can achieve satisfactory control effect. This helps LPG automotive engine to have desirable power output and fuel consumption.