Method and apparatus for controlling combustion of engine having mixed combustion mode

A method of controlling combustion of an engine having a mixture combustion mode where a mixture combustion of diesel and gasoline is carried out and a gasoline combustion mode where only gasoline is burnt, the method comprising:

• determining a combustion mode according to a current driving state of the engine from the mixture combustion mode and the gasoline combustion mode;
• determining a compression ratio corresponding to the combustion mode according to the current driving state of the engine;
• controlling a variable compression ratio device to control a compression ratio of a cylinder to the determined compression ratio;
• determining whether the combustion state of the engine obtained during the combustion after the control to the compression ratio satisfies a set condition for securing a combustion stability;
• and
• performing a compression ratio compensation performed by the variable compression ratio device such that the combustion state of the engine satisfies the set condition with taking a combustion pressure sensor signal as a feedback signal when the set condition is not satisfied.