초록 ▼

In the power supply control system, an electrically heated catalytic converter (EHC) is connected to an alternator output terminal via a switch SW1, and a battery is connected to the alternator via a switch SW2 in parallel with the EHC. A control unit (ECU) for controlling the operation of the switc

In the power supply control system, an electrically heated catalytic converter (EHC) is connected to an alternator output terminal via a switch SW1, and a battery is connected to the alternator via a switch SW2 in parallel with the EHC. A control unit (ECU) for controlling the operation of the switches SW1 and SW2 is provided. When the engine has started, the ECU turns on the SW1 and turns off the SW2 to supply electric power to the EHC directly from the alternator. After the EHC is heated to the activating temperature and starts its catalytic action, the ECU turns on both the switches SW1 and SW2 to supply electric power to the EHC from the battery to maintain the temperature of the EHC. Since the electric power for raising the temperature of the EHC is supplied in the condition where the battery is disconnected from the alternator, the output voltage can be increased to a value higher than a normal output voltage for charging the battery. Therefore, a relatively large electric power can be supplied to the EHC without imposing an excessive load on the battery.

대표청구항 ▼

[ We claim:] [1.] A power supply control system for an electrically heated catalytic converter comprising:an electric generator driven by an internal combustion engine;a battery;an electric heater for heating a catalytic converter disposed in an exhaust gas passage of the engine;a battery charging c

[ We claim:] [1.] A power supply control system for an electrically heated catalytic converter comprising:an electric generator driven by an internal combustion engine;a battery;an electric heater for heating a catalytic converter disposed in an exhaust gas passage of the engine;a battery charging circuit which connects the battery with the generator and supplies an electric current for charging the battery;a catalyst heating circuit which directly connects the heater with the generator and supplies an electric current from the generator to the heater in order to raise the temperature of the catalytic converter to an activating temperature of catalysts in the catalytic converter;a temperature maintaining circuit which connects the heater with the battery and supplies an electric current from the battery to the heater in order to maintain the catalytic converter at the temperature higher than the activating temperature;first power supply control means for cutting off the battery charging circuit and the temperature maintaining circuit and closing the catalyst heating circuit when the engine has started, thereby heating the catalytic converter to the activating temperature; andsecond power supply control means for cutting off the catalyst heating circuit and closing the battery charging circuit and the temperature maintaining circuit when the temperature of the catalysts has reached the activating temperature, thereby charging the battery and, simultaneously, maintaining the catalytic converter at the temperature higher than the activating temperature.