Engine control device

Abstract

The invention discloses an engine control device capable of reducing rewriting time of a non-volatile memory and provided with the non-volatile memory (11) and a control unit (10). The control unit (10) corrects a basic fuel emitted dose Ti and calculates a fuel emitted dose T according to a correction coefficient K, a feedback correction dose Kfb, an air-fuel ratio study correction coefficient Kaf and a voltage correction amount Tb, and outputs a driving signal corresponding to the calculated fuel emitted dose to a fuel emitting component (27). In the engine control device, the control unit (10) calculates an alcohol concentration estimate value Klrn according to the feedback correction dose Kfb when an air-fuel ratio study mode is formed, and stores the calculated alcohol concentration estimate value Klrn into the non-volatile memory (11) when the absolute value of the difference between the calculated alcohol concentration estimate value Klrn and the alcohol concentration estimate value Keep stored in the non-volatile memory (11) is over a preset value and an actual rotate speed Ne of the engine is in a preset range.

Description

technical field [0001] The present invention relates to an engine control device that uses a biological material containing plants as raw materials in a vehicle that cannot use a backup RAM such as a two-wheeled vehicle using a small-capacity battery or a vehicle that does not use a battery. Even when fueled with alcohol such as ethanol, the engine can be operated efficiently. Background technique [0002] In recent years, a flexible fuel vehicle (FFV: Flexible Fuel Vehicle) capable of running on fuel containing alcohol or only alcohol in addition to gasoline fuel has been put into practical use. In this FFV, in order to maintain the actual rotational speed of the engine with various fuels, it is necessary to correct the fuel injection amount. [0003] A method has been proposed in which the alcohol concentration is estimated based on an air-fuel ratio feedback correction coefficient calculated based on the exhaust air-fuel ratio, and the fuel injection amount is corrected ...

AI Technical Summary

Problems solved by technology

[0005] However, in the conventional method of correcting the fuel injection amount as described above, in a vehicle that cannot use a backup RAM such as a two-wheeled vehicle using a small-capacity battery or a vehicle that does not use a battery, the estimated alcohol cannot be calculated. The concentration is stored in the backup RAM, so it is necessary to write the estimated value of the alcohol concentration to the non-volatile memory

However, there is an upper limit to the number of rewriting times of the non-volatile memory, and if the storage process is performed every time the alcohol concentration is estimated, the upper limit of the number of rewriting times of the non-volatile memory may be exceeded

If the upper limit of the number of rewriting times of the nonvolatile memory is exceeded, the estimated value of the alcohol concentration cannot be stored, and there is a problem that the fuel injection amount cannot be corrected, and the phenomenon of too rich / too lean occurs

[0006] In addition, since the feedback correction coefficient is not initialized when the alcohol concentration is estimated, there is a problem that the fuel injection amount is double-corrected using the estimated alcohol concentration and the feedback correction coefficient, resulting in a phenomenon of too rich / too lean

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