Patent ID: 8756924
Filing Date: 2014-06-24
Classification: F01N,F02D,F02N,Y02T

Abstract:
1. A catalyst heating system comprising: a first electronic circuit configured to monitor at least one of (i) a first temperature of a non-electrically heated catalyst (EHC) of a catalyst assembly in an exhaust system of an engine and (ii) an active catalyst volume of the catalyst assembly; a second electronic circuit configured to select an EHC heating mode and generate a mode signal based on the at least one of the first temperature and the active catalyst volume; a third electronic circuit configured to control current to an EHC of the catalyst assembly based on the mode signal; a fourth electronic circuit configured to monitor a second temperature of the EHC; and a fifth electronic circuit configured to compare the second temperature to an EHC convection temperature and generate a first comparison signal, wherein the EHC convection temperature is a predetermined amount greater than a predetermined non-EHC convection temperature, wherein the second electronic circuit is configured to, while current is supplied to the EHC, select an air pumping mode to prevent the first temperature from exceeding the predetermined non-EHC convection temperature, and wherein the air pumping mode includes at least one of (i) rotating a crankshaft of the engine while the engine is deactivated, and (ii) activating an air pump.