米勒循环技术与高压缩比技术是目前国内外混合动力发动机中的先进关键技术。采用仿真模拟的方法，在一款1.2 L涡轮增压缸内直喷3缸汽油发动机工作过程仿真模型上搭载米勒循环技术与高压缩比技术，对米勒循环、高压缩比在燃油经济性方面的影响规律以及二者间的相关性进行了研究。研究结果表明：单独采用米勒循环技术时，无法有效提高发动机燃油经济性；单独采用高压缩比技术时，会产生严重的爆震现象，仅在一定条件下可以提高发动机燃油经济性；米勒循环技术与高压缩比技术在抑制爆震方面有较强的相关性，因此提高发动机几何压缩比来改善燃油经济性的同时，有必要采用米勒循环技术抑制爆震现象的发生。

Miller cycle and high compression ratio technology are the advanced technologies of spark ignition engine in hybrid vehicle at home and abroad. The influences of Miller cycle and high compression ratio on fuel economy and their correlation were studied with the model of simulating working process for a 1.2L 3-cylinder turbocharged GDI engine. The results showed that the single use of Miller cycle technology cannot improve fuel economy and the single use of high compression ratio can improve fuel economy under certain conditions but will cause severe knock. Miller cycle and high compression ratio technology have a strong correlation in suppressing knock, therefore, it is necessary to adopt Miller cycle to suppress knock while improving fuel economy by increasing geometric compression ratio.