System and method for extracting an intake system hydrocarbon trap

Abstract

The invention provides a system and a method for extracting an intake system hydrocarbon trap. Methods and systems are provided for deep extraction of fuel vapors from an intake system hydrocarbon trap. The purging may include supplying heated air to an intake system hydrocarbon trap via a carbon-filled fuel vapor storage canister including an integrated heater. The heated air operates to release heavier hydrocarbons from the intake system hydrocarbon trap.

Description

Technical Field

[0001] The present description generally relates to methods and systems for purging hydrocarbons from an intake system hydrocarbon trap of a hybrid vehicle. Background Art

[0002] A hybrid vehicle may include an internal combustion engine and an electric motor operating as a propulsion source. The hybrid vehicle may include a traction battery that allows the electric motor to propel the hybrid vehicle for an extended distance (e.g., greater than 60 kilometers). The traction battery may allow the internal combustion engine of the hybrid vehicle to be started less frequently for a long period of time. Additionally, if the engine is started, it may be started for a shorter period of time because a control goal of the hybrid vehicle may be to conserve hydrocarbon-based fuel.

[0003] A hybrid vehicle may also include an air intake system (AIS) hydrocarbon trap in the engine's air intake system. The AIS hydrocarbon trap may reduce the amount of hydrocarbons that may escape from the engine and the engine intake when the engine is stopped (e.g., not rotating and not burning fuel). However, the AIS has a limited hydrocarbon storage capacity, and it may be difficult to extract all or most of the hydrocarbons from the AIS hydrocarbon trap because the engine may be stopped shortly after starting to save fuel. Therefore, if the hydrocarbons are not completely extracted from the AIS hydrocarbon trap before the engine is stopped, there may not be sufficient hydrocarbon storage capacity in the AIS hydrocarbon trap to prevent hydrocarbons from escaping the engine and the AIS. Therefore, it may be desirable to provide a way to extract trapped fuel vapors from the AIS hydrocarbon trap in a short period of time. Summary of the invention

[0004] The inventors herein have recognized the previously mentioned problems and have developed a method for an engine that includes: anticipating a start of the engine; and activating a heater of a carbon-filled fuel vapor storage canister in response to the anticipated start of the engine.

[0005] By anticipating an engine start, a heater integrated with the carbon-filled fuel vapor storage canister may be activated to heat the air prior to the engine start so that a larger amount of fuel vapor may be combusted via the engine even if the engine is operated for a short period of time. For example, if a hybrid vehicle is traveling 100 kilometers to a destination that a vehicle occupant has requested, and the hybrid vehicle's traction battery has only enough charge to travel 50 kilometers, the electric heater may be activated to heat the air that will eventually pass through or through the intake system hydrocarbon trap so that hydrocarbons may be extracted from the intake system hydrocarbon trap.

[0006] The method provides several advantages. Specifically, the method utilizes an existing heater to deeply extract the intake system hydrocarbon trap, so that the available capacity of the intake system hydrocarbon trap to store hydrocarbons can be increased, thereby reducing the financial cost of the system. In addition, the method can reduce the emission of hydrocarbons to the atmosphere. Furthermore, the method can be applied to different evaporative emission systems.

[0007] It will be appreciated that the above summary is provided to introduce in simplified form a series of concepts further described in the detailed description. This is not meant to identify key or essential features of the claimed subject matter, the scope of which is uniquely defined by the claims following the detailed description. Furthermore, the claimed subject matter is not limited to embodiments that address any disadvantages mentioned above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 A high-level block diagram illustrating an exemplary vehicle system is shown.

[0009] Figure 2 and Figure 3 shows that it can be included in Figure 1 Schematic diagram of a fuel system and evaporative emissions control (EVAP) system in an exemplary vehicle system.

[0010] Figure 4 Shown according to Figures 1 to 3 systems and Figure 5 An exemplary sequence of operations for the method.

[0011] Figure 5 A flow chart is shown of an exemplary method for operating a vehicle and its evaporative emissions system. DETAILED DESCRIPTION

[0012] The following description relates to systems and methods for deep extraction of hydrocarbons from an intake system hydrocarbon trap. The intake system may be such as Figure 1 A portion of a hybrid vehicle is shown. A hybrid vehicle may include Figure 2 or Figure 3 Evaporative emissions system as shown. Figure 5 The method can be as follows Figure 4 The sequence shown in FIG. 1 deeply extracts hydrocarbons from the intake system.

[0013] Figure 1An exemplary vehicle propulsion system 100 is shown. The vehicle propulsion system 100 includes an internal combustion engine 110 and a motor 120 (e.g., an electric machine). The motor 120 may be configured to utilize or consume a different energy source than the engine 110. For example, the engine 110 may consume a liquid fuel (e.g., gasoline) to produce an engine output, while the motor 120 may consume electrical energy to produce a motor output. Therefore, a vehicle having the propulsion system 100 may be referred to as a hybrid electric vehicle (HEV).

[0014] The vehicle propulsion system 100 can utilize a variety of different operating modes depending on the operating conditions encountered by the vehicle propulsion system. Some of these modes can enable the engine 110 to be maintained in an off state, in other words, set to a deactivated state, wherein combustion of fuel via the engine is stopped. For example, under selected operating conditions, the motor 120 can propel the vehicle via the drive wheels 130 as indicated by arrow 122, while the engine 110 is deactivated.

[0015] During other operating conditions, the engine 110 may be set to a deactivated state (as described above), while the motor 120 may be operated to charge the energy storage device 150. For example, as indicated by arrow 122, the motor 120 may receive wheel torque from the drive wheel 130, wherein the motor may convert the kinetic energy of the vehicle into electrical energy to be stored at the energy storage device 150 as indicated by arrow 124. This operation may be referred to as regenerative braking of the vehicle. Thus, in some embodiments, the motor 120 may provide a generator function. However, in other embodiments, the generator 160 may alternatively receive wheel torque from the drive wheel 130, wherein the generator may convert the kinetic energy of the vehicle into electrical energy to be stored at the energy storage device 150 as indicated by arrow 162.

[0016] During still other operating conditions, the engine 110 may be operated by combusting fuel received from the fuel system 140 as indicated by arrow 142. For example, when the motor 120 is deactivated, the engine 110 may be operated to propel the vehicle via the drive wheels 130 as indicated by arrow 112. During other operating conditions, both the engine 110 and the motor 120 may each be operated to propel the vehicle via the drive wheels 130 as indicated by arrows 112 and 122, respectively. A configuration in which both the engine and the motor may selectively propel the vehicle may be referred to as a parallel vehicle propulsion system. It should be noted that in some embodiments, the motor 120 may propel the vehicle via a first set of drive wheels, while the engine 110 may propel the vehicle via a second set of drive wheels.

[0017] In other embodiments, the vehicle propulsion system 100 may be configured as a series-type vehicle propulsion system, in which the engine does not directly propel the drive wheels. Instead, the engine 110 may be operated to power the motor 120, which in turn may propel the vehicle via the drive wheels 130, as indicated by arrow 122. For example, during selected operating conditions, the engine 110 may drive the generator 160 as indicated by arrow 116, which in turn may supply electrical energy to one or more of the following: the motor 120 as indicated by arrow 114 or the energy storage device 150 as indicated by arrow 162. As another example, the engine 110 may be operated to drive the motor 120, which in turn may provide a generator function to convert the engine output into electrical energy, where the electrical energy may be stored at the energy storage device 150 for subsequent use by the motor.

[0018] The fuel system 140 may include one or more fuel storage tanks 144 for storing fuel on the vehicle, such as a sealed non-pressure non-integrated fuel supply canister dedicated system (NIRCOS) fuel tank. For example, the fuel tank 144 can store one or more liquid fuels, including but not limited to: gasoline, diesel and alcohol fuels. In some examples, the fuel can be stored on the vehicle as a blend of two or more different fuels. For example, the fuel tank 144 can be configured to store a blend of gasoline and ethanol (e.g., E10, E85, etc.) or a blend of gasoline and methanol (e.g., M10, M85, etc.), whereby these fuels or fuel blends can be delivered to the engine 110, as indicated by arrow 142. Some other suitable fuels or fuel blends can be supplied to the engine 110, where they can be burned at the engine to produce an engine output. The engine output can be used to propel the vehicle as indicated by arrow 112 or to recharge the energy storage device 150 via a motor 120 or a generator 160.

[0019] In some embodiments, energy storage device 150 may be configured to store electrical energy that may be supplied to other electrical loads resident on the vehicle (in addition to the motor), including cabin heating and air conditioning, engine starting, headlights, cabin audio and video systems, etc. As a non-limiting example, energy storage device 150 may include one or more batteries and / or capacitors.

[0020] The control system 190 may communicate with one or more of the engine 110, the motor 120, the fuel system 140, the energy storage device 150, and the generator 160. The control system 190 may receive sensory feedback information from one or more of the engine 110, the motor 120, the fuel system 140, the energy storage device 150, and the generator 160. In addition, the control system 190 may send control signals to one or more of the engine 110, the motor 120, the fuel system 140, the energy storage device 150, and the generator 160 in response to this sensory feedback. The control system 190 may receive an indication of an operator-requested output of the vehicle propulsion system from the vehicle operator 102. For example, the control system 190 may receive sensory feedback from a pedal position sensor 194 in communication with a pedal 192. The pedal 192 may schematically refer to a brake pedal, or alternatively, to a driver demand pedal.

[0021] As indicated by arrow 184, energy storage device 150 may periodically receive electrical energy from a power source 180 that resides external to the vehicle (e.g., not part of the vehicle). As a non-limiting example, vehicle propulsion system 100 may be configured as a plug-in hybrid electric vehicle (HEV), whereby electrical energy may be supplied to energy storage device 150 from power source 180 via power transmission cable 182. During operation of recharging energy storage device 150 from power source 180, power transmission cable 182 may electrically couple energy storage device 150 and power source 180. When operating the vehicle propulsion system to propel the vehicle, power transmission cable 182 may be disconnected between power source 180 and energy storage device 150. Control system 190 may identify and / or control the amount of electrical energy stored at the energy storage device, which amount of electrical energy may be referred to as a state of charge (SOC).

[0022] In other embodiments, the power transmission cable 182 may be omitted, where power may be received wirelessly at the energy storage device 150 from the power source 180. For example, the energy storage device 150 may receive power from the power source 180 via one or more of electromagnetic induction, radio waves, and electromagnetic resonance. Thus, it will be appreciated that any suitable method may be used to recharge the energy storage device 150 from a power source that does not form part of the vehicle, such as from solar or wind power. In this way, the motor 120 may propel the vehicle by utilizing an energy source different from the fuel utilized by the engine 110.

[0023] The fuel system 140 may periodically receive fuel from a fuel source residing outside the vehicle. As a non-limiting example, the vehicle propulsion system 100 may be refueled by receiving fuel via the fuel dispensing device 170, as indicated by arrow 172. In some embodiments, the fuel tank 144 may be configured to store the fuel received from the fuel dispensing device 170 until it is supplied to the engine 110 for combustion. In some embodiments, the control system 190 may receive an indication of the level of fuel stored at the fuel tank 144 via a fuel level sensor. The fuel level stored at the fuel tank 144 (e.g., as identified by the fuel level sensor) may be communicated to the vehicle operator, for example, via a fuel gauge or an indication in the vehicle instrument panel 196.

[0024] The vehicle propulsion system 100 may also include an ambient temperature / humidity sensor 198 and a roll stability control sensor, such as a lateral and / or longitudinal and / or yaw rate sensor 199. The vehicle dashboard 196 may include indicator lights and / or a text-based display in which messages are displayed to the operator. The vehicle dashboard 196 (e.g., a human-machine interface) may also include various input portions for receiving operator input, such as buttons, a touch screen, voice input / recognition, etc. For example, the vehicle dashboard 196 may include a refueling button 197 that the vehicle operator may manually actuate or press to initiate refueling. For example, as described in more detail below, in response to the vehicle operator actuating the refueling button 197, the fuel tank 144 in the vehicle may be depressurized so that refueling may be performed.

[0025] Reference now Figure 2 , a schematic diagram 200 depicting a first vehicle system 206 is shown. In some examples, the vehicle system 206 may be a HEV system, such as a PHEV system. For example, the vehicle system 206 may be connected to Figure 1 However, in other examples, vehicle system 206 may be implemented in a non-hybrid vehicle (eg, equipped with an engine but without a motor operable to at least partially propel the vehicle).

[0026] Vehicle system 206 may include engine system 208 coupled to each of evaporative emission control system 251 (EVAP) and fuel system 140. Engine system 208 may include engine 110 having a plurality of cylinders 230. Engine 110 may include engine intake system 223 and engine exhaust system 225.

[0027] Fresh air may flow into the engine 110 as indicated by arrow 272. Each cylinder may include an intake poppet valve 260 and an intake poppet valve actuator 261. The intake poppet valve actuator 261 may be electrically, mechanically, or hydraulically operated, and if desired, it may maintain the intake valve in an open or closed position throughout the cycle of the engine. Similarly, each cylinder may include an exhaust poppet valve 264 and an exhaust poppet valve actuator 265. The exhaust poppet valve actuator 265 may be electrically, mechanically, or hydraulically operated, and if desired, it may maintain the exhaust valve in an open or closed position throughout the cycle of the engine.

[0028] The engine air intake system 223 may include a throttle 262 in fluid communication with the engine intake manifold 244 via an intake passage 242. In addition, the engine air intake system 223 may include an air box and filter (not shown) positioned upstream of the throttle 262. The engine exhaust system 225 may include an exhaust manifold 248 leading to an exhaust passage 235 that directs exhaust gas to the atmosphere. The evaporative emission control system 251 may supply a mixture of air and fuel to the engine air intake system, or alternatively, fresh air, as indicated by arrow 273. The engine air intake system 223 may include an intake system hydrocarbon trap 210 for trapping hydrocarbons to reduce evaporative emissions when the engine 110 is not burning fuel and air. The intake system hydrocarbon trap 210 is shown as being positioned downstream of the throttle 262, but in other examples, the intake system hydrocarbon trap 210 may be positioned upstream of the throttle 262. The evaporative emission control system may be positioned to supply fresh air or a mixture of air and fuel to the engine intake system 223 upstream of the intake system hydrocarbon trap 210, regardless of whether the intake system hydrocarbon trap 210 is positioned upstream or downstream of the throttle 262. Thus, the evaporative emission system may supply fresh air or a mixture of air and fuel to the engine intake system 223 upstream of the intake system hydrocarbon trap 210.

[0029] The engine exhaust system 225 may include an emission control device 270, which may include one or more exhaust catalysts. For example, the emission control device 270 may include a three-way catalyst, a lean nitrogen oxide (NO x ) one or more of a trap, a particulate filter, an oxidation catalyst, etc. In some examples, flow through emission control device 270 may be sensed via differential pressure sensor 282 .

[0030] It should be understood that other components such as various valves and sensors may be included in the engine system 208. For example, a barometric pressure sensor 213 may be included in the engine intake system 223. In one example, the barometric pressure sensor 213 may be a manifold air pressure (MAP) sensor and may be coupled to the engine intake manifold 244 downstream of the throttle 262. The barometric pressure sensor 213 may rely on a part throttle or a wide open or wide open throttle condition, for example, when the opening of the throttle 262 is greater than a threshold value, in order to accurately determine the barometric pressure. In addition, the engine system may also include an ambient temperature sensor (not shown).

[0031] Fuel system 140 may include a fuel tank 144 coupled to a fuel pump system 221. Fuel pump system 221 may include one or more pumps for supplying fuel to cylinder 230 via fuel injector 266 (although in Figure 2 Only a single fuel injector 266 is shown, but additional fuel injectors may be provided for each cylinder 230) to pressurize the fuel delivered to the cylinder 230. The distribution or relative amounts of the delivered fuel, injection timing, etc. may vary with operating conditions such as engine load, engine knock, exhaust temperature, etc. in response to different operating or degradation states of the fuel system 140, the engine 110, etc. The pressure in the fuel system may be estimated via a fuel tank pressure transducer (FTPT) 156. In one example, the FTPT 156 may be included in the fuel tank 144.

[0032] Fuel system 140 can be any one of non-return fuel system, return fuel system or various other types of fuel systems. Fuel tank 144 can store fuel 224, and the fuel includes multiple fuel blends (for example, fuel with a certain range of alcohol mixing zone), such as gasoline, various gasoline-ethanol blends (including E10, E85) etc. The fuel level sensor 234 arranged in fuel tank 144 can provide the indication (" fuel level input ") to the fuel level to the controller 212 included in control system 190. As depicted, fuel level sensor 234 can include a float connected to a variable resistor. Alternatively, other types of fuel level sensors can be used.

[0033] Vapors generated in the fuel system 140 may be directed to the EVAP system 251 via a first conduit 271 extending between the fuel tank 144 and the charcoal-filled fuel vapor storage canister 222. Air and / or fuel vapors stored in the charcoal-filled fuel vapor storage canister 222 may be directed to the intake manifold 244 via a second conduit 228 (e.g., a passage). A third conduit 227 (e.g., a passage) extends between the charcoal-filled fuel vapor storage canister 222 and an atmospheric port 239.

[0034] A fuel tank isolation valve (FTIV) 252 for isolating the fuel tank during certain conditions is shown positioned along first conduit 271. For example, during engine operation, FTIV 252 may remain closed to reduce the amount of diurnal vapor or "running loss" vapor directed from fuel tank 144 to charcoal-filled fuel vapor storage canister 222. During refueling operations and selected purging conditions, FTIV 252 may be temporarily opened, such as for a certain duration, to direct fuel vapor from fuel tank 144 to charcoal-filled fuel vapor storage canister 222. Additionally, FTIV 252 may also be temporarily opened when fuel tank pressure is above a threshold (e.g., above the mechanical pressure limit of the fuel tank) so that fuel vapor may be released into charcoal-filled fuel vapor storage canister 222 and maintain the fuel tank pressure below the threshold.

[0035] like Figure 2 , FTIV 252 is shown external to the fuel tank, but it is understood that in other examples, FTIV 252 and a section of first conduit 271 may be completely contained within fuel tank 144 without departing from the scope of the present disclosure.

[0036] In some examples, refueling system 219 may include a fuel tank cap 205 for sealing the refueling system from the atmosphere. Refueling system 219 may be coupled to fuel tank 144 via fuel filler pipe 211. During refueling, fuel tank cap 205 may be opened manually, or may be opened automatically in response to a refueling request received at controller 212. A fuel dispensing device (e.g., Figure 1 170) may be received by and thereafter fluidly coupled to the refueling system 219, whereby fuel may be supplied to the fuel tank 144 via the fuel filler pipe 211. Refueling may continue until the fuel dispensing device is manually shut off or until the fuel tank 144 is filled to a threshold fuel level (e.g., until feedback from the fuel level sensor 234 indicates that the threshold fuel level has been reached), at which point a mechanical or otherwise automatic stop of the fuel dispensing device may be triggered.

[0037] The EVAP system 251 may include one or more emission control devices, such as a carbon-filled fuel vapor storage canister 222 filled with a suitable adsorbent, which is configured to temporarily trap fuel vapor (including evaporated hydrocarbons) during a refueling operation. In one example, the adsorbent used may be activated carbon. The EVAP system 251 may also include a canister vent path or third conduit 227 that can direct gases out of the carbon-filled fuel vapor storage canister 222 to the atmosphere when storing or trapping fuel vapors from the fuel system 140. The carbon-filled fuel vapor storage canister may also include an integral heater 245 (e.g., an electric heater) that may be activated to deep purge the carbon-filled fuel vapor storage canister 222 and / or the intake system hydrocarbon trap 210. The integral heater 245 may help release longer chain hydrocarbons from the carbon-filled fuel vapor storage canister 222. The integrated heater 245 may include an electrical heating element, such as an electrically heatable conductive metal, ceramic or carbon element, such as a thermistor. In some embodiments, the integrated heater 245 may include a microwave energy source, or may include a canister jacket coupled to a hot air source or a hot water source. The integrated heater 245 may be coupled to one or more heat exchangers that may facilitate the transfer of heat (e.g., from hot exhaust) to the carbon-filled fuel vapor storage canister 222. The integrated heater 245 may be configured to heat the air within the carbon-filled fuel vapor storage canister 222 and / or directly heat the adsorbent within the carbon-filled fuel vapor storage canister 222. In some embodiments, the integrated heater 245 may be included in a heater compartment coupled to the interior or exterior of the carbon-filled fuel vapor storage canister 222. In some embodiments, the carbon-filled fuel vapor storage canister 222 may be coupled to one or more cooling circuits and / or cooling fans. In this way, the carbon-filled fuel vapor storage canister 222 may be selectively cooled to increase the adsorption of fuel vapor (e.g., before a refueling event). In some examples, integrated heater 245 may include one or more Peltier elements that may be configured to selectively heat or cool carbon-filled fuel vapor storage canister 222 .

[0038] The carbon-filled fuel vapor storage canister 222 may include a buffer zone 222a (or buffer region), each of the carbon-filled fuel vapor storage canister and the buffer zone including an adsorbent. As shown, the volume of the buffer zone 222a may be less than the volume of the carbon-filled fuel vapor storage canister 222 (e.g., be a portion thereof). The adsorbent in the buffer zone 222a may be the same as or different from the adsorbent in the carbon-filled fuel vapor storage canister 222 (e.g., both may include charcoal). The buffer zone 222a may be located within the carbon-filled fuel vapor storage canister 222 such that during canister loading, fuel tank vapors may first be adsorbed within the buffer zone, and then when the buffer zone is saturated, additional fuel tank vapors may be adsorbed in the remaining volume of the carbon-filled fuel vapor storage canister. In contrast, during purging of the carbon-filled fuel vapor storage canister 222, fuel vapor may first be desorbed from the carbon-filled fuel vapor storage canister (e.g., to a threshold amount) before desorbing from the buffer zone 222a. In other words, the loading and unloading of buffer zone 222a may not coincide with the loading and unloading of carbon-filled fuel vapor storage canister 222. Thus, one effect of buffer zone 222a is to inhibit any fuel vapor peaks from flowing from fuel tank 144 to carbon-filled fuel vapor storage canister 222, thereby reducing the likelihood of any fuel vapor peaks traveling to engine 110. After deep purging of hydrocarbons from carbon-filled fuel vapor storage canister 222, air may flow from the atmosphere to engine intake manifold 244.

[0039] In some examples, one or more temperature sensors 232 may be coupled to and / or within the carbon-filled fuel vapor storage canister 222. When the adsorbent in the carbon-filled fuel vapor storage canister 222 adsorbs fuel vapor, heat (adsorption heat) may be generated. Similarly, when the adsorbent in the carbon-filled fuel vapor storage canister 222 desorbs fuel vapor, heat may be consumed. In this way, the adsorption and desorption of fuel vapor by the carbon-filled fuel vapor storage canister 222 may be monitored and estimated based on temperature changes within the carbon-filled fuel vapor storage canister. Additionally, a temperature sensor 209 may be included in or near the intake system hydrocarbon trap 210 to sense the temperature of the intake system hydrocarbon trap and be used to estimate the amount of hydrocarbons stored in the intake system hydrocarbon trap 210.

[0040] The third conduit 227 may also allow fresh air to be drawn into the charcoal filled fuel vapor storage canister 222 while the stored fuel vapors are purged from the fuel system 140 to the engine intake system 223 via the second conduit 228 and the canister purge valve (CPV) 291. For example, the CPV 291 may be a valve that is normally closed, but may be opened during certain conditions so that vacuum from the engine intake manifold 244 may be provided to the charcoal filled fuel vapor storage canister 222 for purging. In some examples, the third conduit 227 may also include an air filter 259 disposed therein downstream of the charcoal filled fuel vapor storage canister 222.

[0041] In some examples, the EVAP system 251 may also include an evaporative level check monitor (ELCM) 295. The ELCM 295 may be disposed in the third conduit 227, between the carbon-filled fuel vapor storage canister 222 and the air filter 259, and may be configured to control ventilation and / or assist in the detection of undesirable evaporative emissions. As an example, the ELCM 295 may include a vacuum pump 297 for applying negative pressure to the fuel system when testing for undesirable evaporative emissions. In some embodiments, the vacuum pump may be configured to be reversible. In other words, the vacuum pump may be configured to apply negative or positive pressure to the EVAP system 251 and the fuel system 140. The ELCM 295 may also include a switching valve (COV) 296 to selectively allow or prevent flow through the ELCM 295. For example, when carbon filled fuel vapor storage canister 222 is being purged of fuel vapors or when intake system hydrocarbon trap 210 is being purged of hydrocarbons, COV 296 may be opened to allow fresh air to flow to the trap and storage canister. COV 296 may be closed when FTIV 252 is closed and fuel vapors are stored in fuel tank 144 .

[0042] The routine for detecting undesirable evaporative emissions may be intermittently performed by the controller 212 on the fuel system 140 to confirm that the fuel system has not degraded. Thus, the undesirable evaporative emissions detection routine may be performed when the engine is off (engine off degradation test) using the engine off natural vacuum (EONV) generated due to changes in temperature and pressure at the fuel tank after the engine is shut down and / or the vacuum supplemented from the vacuum pump. Alternatively, the undesirable evaporative emissions detection routine may be performed while the engine is running by operating the vacuum pump and / or using the engine intake manifold vacuum. The undesirable evaporative emissions test may be performed by the ELCM 295 communicatively coupled to the controller 212.

[0043] The fuel system 140 may be a non-integrated refueling canister dedicated system (NIRCOS) because the fuel tank 144 may be substantially isolable from the carbon-filled fuel vapor storage canister 222, such that the fuel vapor in the fuel tank 144 and the carbon-filled fuel vapor storage canister 222 may be independently controlled as desired (e.g., during refueling). During the period when the fuel tank 144 is fluidly separated from the carbon-filled fuel vapor storage canister 222, fuel vapor pressure may build up within the fuel tank. Therefore, ventilation and decompression control procedures are typically implemented for the NIRCOS fuel tank and its structural reinforcements. For example, a given NIRCOS may include a plurality of valves and vent lines coupled to one or more fuel tanks included therein to ensure that any excess fuel vapor pressure is properly vented or redistributed. In addition, the NIRCOS fuel tank may be constructed of a high tensile strength material (such as heavy steel) and configured with a plurality of supports extending between opposing walls of a given NIRCOS fuel tank so that a greater fuel vapor pressure may be withstood without fuel tank degradation.

[0044] Fuel system 140 may be operated in a plurality of modes by controller 212 by selectively adjusting various valves (e.g., in response to various sensors). For example, fuel system 140 may be operated in a refueling mode (e.g., when a vehicle operator requests a refueling), wherein controller 212 may close FTIV 252. Additionally, fuel system 140 may be operated in a ventilation mode. In the ventilation mode, controller 212 may open FTIV 252 and canister ventilation valve 229 while maintaining CPV 291 closed to direct refueling vapors into carbon-filled fuel vapor storage canister 222 while preventing fuel vapors from being directed into engine intake manifold 244 (and thereby providing a ventilation path for fuel vapors). Thus, opening FTIV 252 may allow refueling vapors to be stored in carbon-filled fuel vapor storage canister 222. After refueling is complete, at least FTIV 252 may be closed again.

[0045] As another example, the fuel system may be operated in a canister purge mode (e.g., after a given emission control device light-off temperature has been reached and while the engine 110 is running), wherein the controller 212 may open the CPV 291 and the canister vent valve 229 while closing the FTIV 252. Herein, the vacuum generated by the engine intake manifold 244 of the (operating) engine 110 may be used to draw fresh air through the third conduit 227 and through the carbon-filled fuel vapor storage canister 222 and the intake system hydrocarbon trap to purge stored fuel vapor into the engine intake manifold 244. Thus, in the canister purge mode, fuel vapor purged from the carbon-filled fuel vapor storage canister 222 may be combusted in the engine 110. The canister purge mode may be continued until the amount or level of fuel vapor stored in the carbon-filled fuel vapor storage canister 222 is below a threshold amount or level.

[0046] In yet another example, the fuel system may be operated in an intake system hydrocarbon trap purging mode. In some examples, a carbon-filled fuel vapor storage canister may be used exclusively to store fuel vapor during fuel tank refills. Since the vehicle is a hybrid vehicle with a relatively large traction battery charge storage capacity, the fuel tank may not be refilled often. Therefore, fuel vapor may be purged from the carbon-filled fuel vapor storage canister, but the engine may be stopped and restarted multiple times between fuel tank refills. The intake system hydrocarbon trap may store fuel vapor each time the engine is stopped due to residual fuel that may be in the engine's intake manifold and other fuel vapor sources in the engine. However, the intake system hydrocarbon trap may lack the capacity to store hydrocarbons generated during two or more engine stop periods (e.g., where the engine is not rotating and not burning fuel). Therefore, it may be desirable to deeply purge the trapped hydrocarbons from the intake system hydrocarbon trap by directing warm fresh air to the intake system hydrocarbon trap via the carbon-filled fuel vapor storage canister and the atmosphere. When the engine 110 is running, warm fresh air may be supplied to the intake system hydrocarbon trap 210 and the engine 110 by opening the CPV 291 , closing the FTIV 252 , and opening the COV 296 .

[0047] Control system 190 including controller 212 is shown receiving information from a plurality of sensors 216 (various examples of which are described herein) and sending control signals to a plurality of actuators 281 (various examples of which are described herein). Controller 212 may be configured as a powertrain control module (PCM). As an example, sensors 216 may include one or more of exhaust gas sensor 237 located in exhaust passage 235 upstream of emission control device 270, temperature sensor 233 located in exhaust passage 235 downstream of emission control device 270, fuel level sensor 234 located in fuel tank 144, temperature sensor 232 located in carbon-filled fuel vapor storage canister 222, temperature sensor 209, and FTPT 156. Other sensors, such as pressure, temperature, air-fuel ratio, and composition sensors, may be coupled to various locations in vehicle system 206. As additional or alternative examples, actuators 281 may include fuel injectors 266, throttle 262, FTIV 252, CPV 291, COV 296, and integrated heater 245. Controller 212 may receive input data from sensors 216, process the input data, and trigger actuators 281 in response to the processed input data based on instructions or code programmed in non-transitory memory therein, the instructions or code corresponding to one or more control routines.

[0048] Reference now Figure 3 , a schematic diagram 300 depicting a second vehicle system 306 is shown. Figure 3 The second vehicle system 306 shown includes a number of Figure 2 The same components as those of the first vehicle system 206 are shown. Unless otherwise indicated, Figure 3 of Figure 2 Components that are identical to the components shown are labeled with the same reference numerals and these components operate as previously described. Therefore, for the sake of brevity, the description of each of these components is omitted. Figure 3 of Figure 2 The parts are different parts.

[0049] The second system 306 includes a canister ventilation valve (CVV) 302 instead of the ELCM 295. The CVV 302 may be opened along with the CPV 291 when purging hydrocarbons from the carbon filled fuel vapor storage canister 222 and / or the intake system hydrocarbon trap 210. Additionally, when the fuel tank 144 is filled with fuel, the CVV 302 may be opened and the CPV 291 may be closed so that fuel vapors may be stored in the carbon filled fuel vapor storage canister 222.

[0050] therefore, Figure 1 and Figure 2A system for a vehicle is provided, the system comprising: an internal combustion engine, the internal combustion engine comprising an intake system; a carbon-filled fuel vapor storage canister, the carbon-filled fuel vapor storage canister comprising a heater; an intake system hydrocarbon trap, the intake system hydrocarbon trap being positioned within the intake system; and a controller, the controller comprising executable instructions stored in a non-transitory memory, the executable instructions causing the controller to activate the heater to heat air flowing through the carbon-filled fuel vapor storage canister to the intake system hydrocarbon trap. In a first example, the system comprises: wherein the heater is activated in response to an expected start of the internal combustion engine. In a second example, which may include the first example, the system further comprises additional instructions for opening a canister purge valve and a canister vent valve. In a third example, which may include one or both of the first and second examples, the system further comprises additional instructions for opening a canister purge valve and a switching valve. In a fourth example, which may include one or more of the first to third examples, the system further includes additional instructions for purging the carbon-filled fuel vapor storage canister so that hydrocarbons are purged from the carbon-filled fuel vapor before activating the heater. In a fifth example, which may include one or more of the first to fourth examples, the system further includes an electric motor configured to propel the vehicle. In a sixth example, which may include one or more of the first to fifth examples, the system further includes additional executable instructions that cause the controller to activate the heater while the electric motor propels the vehicle. In a seventh example, which may include one or more of the first to sixth examples, the system further includes a conduit extending from the carbon-filled fuel vapor storage canister to a location in the intake system upstream of the hydrocarbon trap.

[0051] Now go to Figure 4 , showing that according to Figures 1 to 3 systems and Figure 4 An exemplary engine operating sequence for the method of FIG. Figure 4 The sequence of operations can be Figures 1 to 3 system and Figure 4 The vertical lines at times t0-t4 represent times of interest during the sequence of operations. The graphs are aligned in time.

[0052] since Figure 4The first graph from the top is a graph of engine operating state versus time. The vertical axis represents the engine operating state, and when the trace 402 is at a higher level near the vertical axis arrow, the engine operating state indicates that the engine is on (e.g., spinning and burning fuel). When the trace 402 is at a lower level near the horizontal axis, the engine operating state indicates that the engine is off (e.g., not spinning and not burning fuel). The horizontal axis represents time, and time increases from the left side of the graph to the right side of the graph. The trace 402 represents the engine operating state.

[0053] since Figure 4 The second graph from the top of is a graph of the carbon filled fuel vapor storage canister heater state versus time. The vertical axis represents the operating state of the carbon filled fuel vapor storage canister heater state, and when trace 404 is at a higher level near the vertical axis arrow, the carbon filled fuel vapor storage canister heater is activated. When trace 404 is near the horizontal axis, the carbon filled fuel vapor storage canister heater is not activated. The horizontal axis represents time, and time increases from the left side of the graph to the right side of the graph. Trace 404 represents the carbon filled fuel vapor storage canister heater state.

[0054] since Figure 4 The third graph from the top is a graph of COV or CVV status versus time. The vertical axis represents the COV / CVV status, and when the trace 406 is horizontal near the vertical axis arrow, the COV / CVV is on. When the trace 406 is near the level of the horizontal axis, the COV / CVV is completely off. The horizontal axis represents time, and time increases from the left side of the graph to the right side of the graph. The trace 406 represents the COV / CVV status.

[0055] since Figure 5 The fourth graph from the top of is a graph of CPB status versus time. The vertical axis represents CPV, and when trace 408 is near the horizontal axis, the CPV status indicates that the CPV is closed. When trace 408 is near the vertical axis arrow, the CPV is open. The horizontal axis represents time, and time increases from the left side of the graph to the right side of the graph. Trace 408 represents the CPV status.

[0056] since Figure 4The fifth graph from the top of is a graph of the amount of hydrocarbons (HC) stored in the carbon filled fuel vapor storage canister versus time. The vertical axis represents the amount of HC stored in the carbon filled fuel vapor storage canister, and the amount of hydrocarbons increases in the direction of the vertical axis arrow. The horizontal axis represents time, and time increases from the left side of the graph to the right side of the graph. Trace 410 represents the amount of hydrocarbons stored in the carbon filled fuel vapor storage canister.

[0057] since Figure 4 The sixth graph from the top of FIG. 4 is a graph of the amount of hydrocarbons (HC) stored in an air intake system (AIS) HC trap versus time. The vertical axis represents the amount of HC stored in the air intake system HC trap, and the amount of hydrocarbons increases in the direction of the vertical axis arrow. The horizontal axis represents time, and time increases from the left side of the graph to the right side of the graph. Trace 412 represents the amount of hydrocarbons stored in the air intake system HC trap.

[0058] At time t0, the engine is operating and the carbon filled fuel vapor storage canister heater is activated to deep purge the carbon filled fuel vapor storage canister. Fuel vapors from the canister are combusted in the engine. The COV / CVV is fully closed and the CPV is open to allow fuel vapors from the carbon filled fuel vapor storage canister to enter the engine. The amount of hydrocarbons stored in the carbon filled fuel vapor storage canister is reduced. The amount of hydrocarbons stored in the intake system hydrocarbon trap is low.

[0059] At time t1, the engine continues to operate and because the amount of hydrocarbons stored in the carbon filled fuel vapor storage canister is low, the carbon filled fuel vapor storage canister heater is deactivated to save energy. Shortly after deactivating the carbon filled fuel vapor storage canister heater, the COV / CVV remains closed and the CPV is closed. The amount of hydrocarbons stored in the intake system hydrocarbon trap remains low.

[0060] At time t2, the engine is stopped in response to vehicle operating conditions, and the carbon-filled fuel vapor storage canister heater remains deactivated. The COV / CVV remains fully closed, and shortly thereafter, the CPV is fully closed. The amount of hydrocarbons stored in the carbon-filled fuel vapor storage canister approaches zero, and the amount of hydrocarbons stored in the intake system hydrocarbon trap approaches zero.

[0061] Between time t2 and time t3, the engine remains off and the carbon filled fuel vapor storage canister heater remains off. The COV / CVV remains fully closed and the CPV remains fully closed. As fuel from the intake manifold and cylinders of the engine is stored in the hydrocarbon trap, the amount of hydrocarbons stored in the intake system hydrocarbon trap begins to increase.

[0062] At time t3, the carbon filled fuel vapor storage canister heater is activated in response to an anticipated engine start. The engine start may be anticipated based on the state of charge (SOC) of the battery and the distance to the destination. By activating the carbon filled fuel vapor storage canister heater, the air in the carbon filled fuel vapor storage canister may be heated to deep purge the intake system hydrocarbon trap. The COV / CVV and CPV remain fully closed. The amount of carbon stored in the carbon filled fuel vapor storage canister remains low, and the amount of hydrocarbons stored in the intake system hydrocarbon trap continues to increase.

[0063] At time t4, the engine is started and the carbon-filled fuel vapor storage canister heater remains activated. Shortly after the engine is started, the COV / CVV and CPV open to allow heated air from the carbon-filled fuel vapor storage canister to pass through and / or through the intake system hydrocarbon trap, which causes hydrocarbons to be released from the trap and combusted in the engine. Therefore, the amount of hydrocarbons stored in the intake system hydrocarbon trap is reduced, and because the air passing through or through the intake hydrocarbon trap is warm, hydrocarbons are released from the intake system hydrocarbon trap at a higher rate than if the air was not heated.

[0064] In this way, the heater in the carbon filled fuel vapor storage canister can be activated to deeply purge fuel vapors from the intake system hydrocarbon trap. The heated air can cause the hydrocarbon trap to release hydrocarbons at a faster rate and in greater amounts than if the air passing through the hydrocarbon trap was not heated.

[0065] Reference now Figure 5 , a high-level flowchart of an exemplary method 500 for operating an EVAP system is shown. The method 500 may be implemented at least in part as a program stored in a computer such as a computer program product. Figures 1 to 3 The executable instructions in the non-transitory memory of the controller in the system shown. In addition, Figure 5 Methods may include actions taken in the physical world to transform the system (such as Figures 1 to 3 Furthermore, the method 500 may be used in conjunction with Figures 1 to 3 The systems shown in are executed cooperatively. Figure 5The method can also provide Figure 4 At least some portion of the sequence of operations shown in .

[0066] At 502, it is determined whether there is a request to refill the fuel tank and whether the pressure in the fuel tank is greater than a threshold pressure. If so, the answer is yes and method 500 proceeds to 520. Otherwise, the answer is no and method 500 proceeds to 504. In one example, a user may press a button to indicate that a refuel is requested and open the fuel access door and reduce the pressure in the fuel tank. Pressure may build up in the fuel tank due to diurnal heating of the fuel.

[0067] At 520 , method 500 closes the CPV and opens the COV / CVV. Additionally, if the vehicle includes a FTIV, the FTIV is opened. This allows fuel vapor to flow from the fuel tank to a carbon-filled fuel vapor storage canister that can store fuel vapor. Method 500 proceeds to 522 .

[0068] At 522 , method 500 stores hydrocarbons generated from filling the fuel tank in a carbon filled fuel vapor storage canister. Once refueling is complete, the COV / CVV, CPV, and FTIV are fully closed. Method 500 proceeds to exit.

[0069] At 504 , method 500 judges whether the engine is running (eg, spinning and burning fuel). If so, the answer is yes and method 500 proceeds to 506 . Otherwise, the answer is no and method 500 proceeds to 530 .

[0070] At 530, method 500 determines whether an engine start is expected to occur within a threshold amount of time (e.g., within 15 minutes). In one example, method 500 may anticipate that the engine will start or anticipate an engine start based on the distance to the vehicle's destination and the traction battery state of charge. If the amount of charge stored in the traction battery is less than the amount of charge that the vehicle is expected to consume to reach the vehicle's destination, method 500 may anticipate that the vehicle's engine will start during the vehicle's current trip. Method 500 may estimate when the engine will start based on attributes of the route the vehicle is traveling (e.g., road grade, etc.) and the charge consumption of traveling the route. Method 500 may predict an engine start within a predetermined time period in the future (e.g., 15 minutes). If method 500 determines that the engine is expected to start within a predetermined amount of time, the answer is yes and method 500 proceeds to 532. Otherwise, the answer is no and method 500 proceeds to 506.

[0071] At 532 , method 500 activates a heater in the carbon filled fuel vapor storage canister. The heater is activated to heat air entering and passing through the carbon filled fuel vapor storage canister. Thus, method 500 may preheat the air in the carbon filled fuel vapor storage canister so that when the engine is started, warm air may be delivered to the engine without an additional waiting period so that the hydrocarbon trap may be purged more quickly, which may be desirable for engines that are not started frequently so that the trap may be fully emptied more quickly. Method 500 proceeds to 506 .

[0072] At 506, method 500 judges whether there is fuel vapor stored in the charcoal filled fuel vapor storage canister. Fuel vapor from a previous charge of the fuel tank may be stored in the charcoal filled fuel vapor storage canister. If method 500 judges that there is fuel vapor stored in the charcoal filled fuel vapor storage canister, the answer is yes and method 500 proceeds to 508. Otherwise, the answer is no and method 500 proceeds to 540.

[0073] At 508 , method 500 activates a heater in the char-filled fuel vapor storage canister to facilitate release of fuel vapor from the char. Method 500 proceeds to 510 .

[0074] At 510 , method 500 opens the CPV from a fully closed state, closes the COV / CVV, and opens the FTIV (if present). By opening the CPV, FTIV, and closing the COV / CVV, fuel vapors from the carbon filled fuel vapor storage canister and the fuel tank may be drawn into the engine. Method 500 proceeds to 512 .

[0075] At 512 , method 500 combusts fuel vapor drawn from the carbon filled fuel vapor storage canister to the engine. Method 500 proceeds to exit.

[0076] At 540, method 500 judges whether more than a threshold amount of fuel vapor is stored in the intake system hydrocarbon trap. In one example, method 500 may estimate the amount of fuel vapor stored in the intake system hydrocarbon trap based on engine temperature, ambient air temperature, engine fuel pool model output, and other engine operating conditions. If method 500 judges that more than a threshold amount of fuel vapor is stored in the intake system hydrocarbon trap, the answer is yes and method 500 proceeds to 542. Otherwise, the answer is no and method 500 proceeds to 548.

[0077] At 542 , method 500 activates a heater in the char-filled fuel vapor storage canister to facilitate release of fuel vapor from the char. Method 500 proceeds to 544 .

[0078] At 544, method 500 opens the CPV and opens the COV / CVV. The FTIV is fully closed (if present). By opening the CPV and COV / CVV, air may be drawn from the atmosphere, heated, and sent to the intake system hydrocarbon trap to promote release of fuel vapors from the intake system hydrocarbon trap, such that a heater need not be provided in the engine intake system. Since the engine intake manifold pressure may be lower than atmospheric pressure, air may be drawn into the engine intake manifold. Method 500 proceeds to 546.

[0079] At 546 , method 500 combusts fuel vapors released from the intake system hydrocarbon trap. Method 500 proceeds to 548 .

[0080] At 548, method 500 closes the CPV, closes the COV / CVV, and deactivates the heater in the carbon-filled fuel vapor storage canister when the amount of hydrocarbons stored in the intake system hydrocarbon trap is less than a threshold amount or when the flow of hydrocarbons from the trap is less than a threshold amount. The amount of hydrocarbons flowing out of the trap may be determined via a hydrocarbon sensor, and the amount of hydrocarbons stored in the hydrocarbon trap may be estimated via a model and vehicle operating conditions. Method 500 proceeds to exit.

[0081] therefore, Figure 5 A method for an engine is provided, the method comprising: anticipating a start of the engine; and activating a heater of a carbon-filled fuel vapor storage canister in response to the expected start of the engine. In a first example, the method further comprises propelling the vehicle via the electric machine while anticipating the start of the engine. In a second example, which may include the first example, the method further comprises estimating that an amount of hydrocarbons stored in an intake system hydrocarbon trap exceeds a first threshold amount of hydrocarbons. In a third example, which may include one or both of the first and second examples, the method further comprises: purging hydrocarbons stored in the carbon-filled fuel vapor storage canister before activating the heater so that less than a second threshold amount of hydrocarbons are stored in the carbon-filled fuel vapor storage canister. In a fourth example, which may include one or more of the first to third examples, the method further comprises supplying heated air to the intake system hydrocarbon trap via flowing air through the carbon-filled fuel vapor storage canister. In a fifth example, which may include one or more of the first to fourth examples, the method comprises: wherein the heated air is supplied upstream of the intake system hydrocarbon trap. In a sixth example, which may include one or more of the first to fifth examples, the method further includes opening a canister purge valve to flow air through the carbon filled fuel vapor storage canister and through an intake system hydrocarbon trap.

[0082] Figure 5 The method also provides a method for an engine, the method comprising: causing heated air to flow from a carbon-filled fuel vapor storage canister to an intake system hydrocarbon trap, wherein the air is heated via a heater installed in the carbon-filled fuel vapor storage canister. In a first example, the method also includes opening a canister purge valve and a canister vent valve to cause heated air to flow out of the carbon-filled fuel vapor storage canister. In a second example that may include the first example, the method also includes causing heated air to flow out of the carbon-filled fuel vapor storage canister in response to engine start. In a third example that may include one or both of the first and second examples, the method includes: wherein the heater is activated before the engine is started when the engine is not rotating. In a fourth example that may include one or more of the first to third examples, the method also includes burning hydrocarbons released from the intake system hydrocarbon trap while causing heated air to flow out of the carbon-filled fuel vapor storage canister.

[0083] It should be noted that the exemplary control and estimation procedures included herein can be used with various engine and / or vehicle system configurations. The control methods and procedures disclosed herein can be stored as executable instructions in a non-transitory memory and can be executed by a control system including a controller in combination with various sensors, actuators and other engine hardware. The specific procedures described herein may represent one or more of any number of processing strategies (such as event-driven, interrupt-driven, multi-tasking, multi-threading, etc.). To this end, the various actions, operations and / or functions shown may be executed in the sequence described, executed in parallel, or omitted in some cases. Similarly, the processing order is not necessarily required to achieve the features and advantages of the example embodiments described herein, but is provided for ease of illustration and description. One or more of the actions, operations and / or functions shown may be repeatedly performed according to the specific strategy used. In addition, the described actions, operations and / or functions may graphically represent the code in the non-transitory memory of a computer-readable storage medium that will be programmed into the engine control system, wherein the described actions are implemented by executing instructions in a system including various engine hardware components in conjunction with an electronic controller.

[0084] It should be understood that the configurations and procedures disclosed herein are exemplary in nature, and these specific embodiments should not be considered to be limiting, as many variations are possible. For example, the above technology can be applied to V-6 cylinders, inline 4 cylinders, inline 6 cylinders, V-12 cylinders, opposed 4 cylinders, and other engine types. In addition, unless explicitly stated to the contrary, the terms "first", "second", "third", etc. are not intended to represent any order, position, quantity, or importance, but are only used as marks to distinguish one element from another. The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and configurations and other features, functions, and / or properties disclosed herein.

[0085] As used herein, unless otherwise specified, the term "about" is interpreted to mean ±5% of the stated range.

[0086] The appended claims particularly point out certain combinations and subcombinations regarded as novel and non-obvious. These claims may refer to "an" element or "a first" element or the equivalent thereof. Such claims may be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties may be claimed by amendment of the present claims or by presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, are also deemed to be included in the subject matter of the present disclosure.

[0087] According to the present invention, a method for an engine includes: anticipating a start of the engine; and activating a heater of a carbon-filled fuel vapor storage canister in response to the anticipated start of the engine.

[0088] In one aspect of the invention, the method includes propelling the vehicle via the electric machine while anticipating starting of the engine.

[0089] In one aspect of the present invention, the method includes estimating that an amount of hydrocarbons stored in an intake system hydrocarbon trap exceeds a first threshold amount of hydrocarbons.

[0090] In one aspect of the present invention, the method includes purging hydrocarbons stored in the charcoal filled fuel vapor storage canister prior to activating the heater such that less than a second threshold amount of hydrocarbons are stored in the charcoal filled fuel vapor storage canister.

[0091] In one aspect of the present invention, the method includes supplying heated air to an intake system hydrocarbon trap via flowing the air through a carbon-filled fuel vapor storage canister.

[0092] In one aspect of the present invention, heated air is supplied upstream of an intake system hydrocarbon trap.

[0093] In one aspect of the present invention, the method includes opening a canister purge valve to flow air through a carbon filled fuel vapor storage canister and through an intake system hydrocarbon trap.

[0094] According to the present invention, a system for a vehicle is provided, the system comprising: an internal combustion engine, the internal combustion engine comprising an intake system; a carbon-filled fuel vapor storage canister, the carbon-filled fuel vapor storage canister comprising a heater; an intake system hydrocarbon trap, the intake system hydrocarbon trap being positioned within the intake system; and a controller, the controller comprising executable instructions stored in a non-transitory memory, the executable instructions causing the controller to activate the heater to heat air flowing through the carbon-filled fuel vapor storage canister to reach the intake system hydrocarbon trap.

[0095] According to one embodiment, the heater is activated in response to an expected start of the internal combustion engine.

[0096] According to one embodiment, the invention also features additional instructions for opening the canister purge valve and the canister vent valve.

[0097] According to one embodiment, the invention also features additional instructions for opening the canister purge valve and the switching valve.

[0098] According to one embodiment, the present invention also features additional instructions for purging the charcoal filled fuel vapor storage canister such that hydrocarbons are purged from the charcoal filled fuel vapor storage canister prior to activating the heater.

[0099] According to one embodiment, the invention also features an electric machine configured to propel the vehicle.

[0100] According to one embodiment, the invention also features additional executable instructions that cause the controller to activate the heater while the motor is propelling the vehicle.

[0101] According to one embodiment, the invention also features a conduit extending from the carbon-filled fuel vapor storage canister to a location in the intake system upstream of an intake system hydrocarbon trap.

[0102] According to the present invention, a method for an engine includes flowing heated air from a carbon-filled fuel vapor storage canister to an intake system hydrocarbon trap, wherein the heated air is heated via a heater mounted in the carbon-filled fuel vapor storage canister.

[0103] In one aspect of the present invention, the method includes opening a canister purge valve and a canister vent valve to allow heated air to flow from a charcoal filled fuel vapor storage canister.

[0104] In one aspect of the present invention, the method includes flowing heated air from a charcoal filled fuel vapor storage canister in response to engine starting.

[0105] In one aspect of the present invention, the heater is activated before the engine is started when the engine is not rotating.

[0106] In one aspect of the present invention, the method includes burning hydrocarbons released from an intake system hydrocarbon trap while flowing heated air from a carbon-filled fuel vapor storage canister.

Claims

1. A method for an engine, comprising: anticipating starting of said engine; as well as A heater of a charcoal-filled fuel vapor storage canister is activated in response to an anticipated start of the engine. 2 . The method of claim 1 , further comprising propelling the vehicle via the electric machine while anticipating the starting of the engine. 3 . The method of claim 2 further comprising estimating that an amount of hydrocarbons stored in an intake system hydrocarbon trap exceeds a first threshold amount of hydrocarbons.

4. The method of claim 3, further comprising: Prior to activating the heater, hydrocarbons stored in the charcoal-filled fuel vapor storage canister are purged such that less than a second threshold amount of hydrocarbons are stored in the charcoal-filled fuel vapor storage canister. 5 . The method of claim 4 , further comprising supplying heated air to the intake system hydrocarbon trap via flowing air through the carbon filled fuel vapor storage canister.

6. The method of claim 5, wherein the heated air is supplied upstream of the intake system hydrocarbon trap. 7 . The method of claim 6 , further comprising opening a canister purge valve to allow air to flow through the carbon filled fuel vapor storage canister and through the intake system hydrocarbon trap.

8. A system for a vehicle, comprising: An internal combustion engine, the internal combustion engine comprising an intake system; a carbon filled fuel vapor storage canister including a heater; an intake system hydrocarbon trap, the intake system hydrocarbon trap being positioned within the intake system; as well as A controller including executable instructions stored in non-transitory memory causes the controller to activate the heater to heat air flowing through the carbon-filled fuel vapor storage canister to the intake system hydrocarbon trap.

9. The system of claim 8, wherein the heater is activated in response to an anticipated start of the internal combustion engine.

10. The system of claim 9 further comprising additional instructions for opening a canister purge valve and a canister vent valve.

11. The system of claim 9 further comprising additional instructions for opening a canister purge valve and a switching valve.

12. The system of claim 8 further comprising additional instructions for purging said charcoal filled fuel vapor storage canister such that hydrocarbons are purged from said charcoal filled fuel vapor storage canister prior to activating said heater.

13. The system of claim 8, further comprising a motor configured to propel the vehicle.

14. The system of claim 13 further comprising additional executable instructions that cause the controller to activate the heater while the motor is propelling the vehicle.

15. The system of claim 14 further comprising a conduit extending from the carbon-filled fuel vapor storage canister to the air intake system at a location upstream of the air intake system hydrocarbon trap.

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