ELECTRIC GRID UTILIZATION FOR CONTROLLING CANISTER TEMPERATURE TO IMPROVE PURGE EFFICIENCY IN PHEV’S
Publication Date: 2014-Feb-04
The IP.com Prior Art Database
Page 01 of 1
ELECTRIC GRID UTILIZATION FOR CONTROLLING CANISTER TEMPERATURE TO IMPROVE PURGE EFFICIENCY IN PHEV'S
Vehicles sold in North America and other markets contain a carbon canister that adsorbs refueling (North America only), diurnal and running loss vapors. When the engine is running, by duty cycling the canister purge valve, the manifold vacuum draws clean air from the fresh side of the canister. The air flows through the carbon canister and removes hydrocarbons embedded in the activated carbons. This is commonly known as "purging". The desorbed hydrocarbons are mixed into the fuel vapor and combusted in engine. With limited engine purge time in a PHEV vehicle, it's very challenging for the carbon canister to be cleaned out all the time. In order to pass emission testing, the canister must be purged out thoroughly. It is well known phenomenon that a heated canister will result in better desorption of hydrocarbons from the activated carbon. However, during refueling event, the canister is desired to be cool in order to maximize vapor adsorption. A method to heat/cool the canister to optimize the refueling and purging functions is desirable.
The idea of the invention is to enclose the carbon canister with a piezo-electric material and power the heaters off the electric grid when the PHEV vehicle is being charged. This provides a heat storage bank for the canister which will be released when purging occurs. Wrapping the canister with alternating cool/hot surfac...