| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide the EGR gas flow rate estimation device of an internal combustion engine capable of further enhancing estimation accuracy of an EGR gas flow rate by performing arithmetic operation considering pulsation of the EGR gas. <P>SOLUTION: The upstream side pressure PEX and the downstream side pressure PBA of an EGR valve 23 in an EGR passage 22 are acquired and variation of a pressure ratio PEGRR in a prescribed period is converted to a sine wave SW. A pressure function ΦSW for computing the flow rate GEGR of the EGR gas and having the pressure ratio PEGRR as a variable is computed on the basis of the sine wave SW and the flow rate GEGR of the EGR gas passing through the EGR valve 23 in the EGR passage 22 in the prescribed period is computed on the basis of the pressure function ΦSW. <P>COPYRIGHT: (C)2012,JPO&INPIT |
