| 摘要 |
In an initial predetermined period of time for supplying electric power to the electrically heated catalyst mounted on the vehicle, a maximum of electric power is supplied from the power source to simplify the complex heat control operation. Simultaneously with starting of the engine, the electrically heated catalyst is connected to the power source to start supplying the electric power, and a maximum electric power permitted by the power source is supplied for a first predetermined period of time after which the electrically heated catalyst is just about to be activated. After the first predetermined period of time has passed, the electric resistance of the electrically heated catalyst is measured until a second predetermined period of time elapses. Depending upon the thus measured electric resistance, the amount of electric power supplied from the power source to the electrically heated catalyst is controlled by feedback so that the electric resistance of the electrically heated catalyst is maintained at a predetermined target electric resistance. The power source for the electrically heated catalyst may be the alternator driven by the drive source of the vehicle. Furthermore, the power source may be the alternator from starting the engine until the first predetermined period of time elapses, and may, then, be the battery from the elapse of the first predetermined period of time until the second predetermined period of time elapses. Being controlled as described above, the electric power is supplied to the electrically heated catalyst, immediately after starting the engine, easily and reliably.
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