Method and system for recovering waste heat from a turbocharged system

Abstract

The present disclosure provides "Methods and systems for recovering waste heat from turbocharged systems with thermoelectric generators." Methods and systems are provided for recovering waste heat from turbocharged systems with thermoelectric generators and diagnosing turbocharged systems. In one example, a method can include adjusting one or more engine operating parameters based on an amount of electrical current generated from one or more thermoelectric generators coupled to a turbocharger.

Description

Technical Field

[0001] This specification relates generally to methods and systems for energy generation in vehicles, and more specifically to methods and systems for recovering waste heat using thermoelectric generators and for diagnosing turbocharged systems. Background Technology

[0002] To reduce engine fuel consumption and emissions, vehicles are constantly being adapted for more efficient operation. One mechanism for improving vehicle efficiency involves electrically operating certain accessory components of the vehicle (such as the air conditioning compressor) instead of mechanically operating them via the vehicle's engine. However, additional electrical loads on the vehicle often need to be generated via the vehicle's alternator, which can exacerbate fuel consumption and emissions.

[0003] Various methods for generating electricity in vehicles have been proposed. In one example shown in U.S. Patent Publication No. 2017 / 0074157 to Mitkari et al., a thermoelectric generator is coupled to the exhaust valve housing of a turbocharger turbine. The thermoelectric generator generates electricity via a heat flux from a high-temperature zone (exhaust valve housing) to a low-temperature zone (coolant supply), and the electricity can be used by accessory components or stored in a battery.

[0004] However, the inventors have recognized some problems with the above-described method. Due to the location of the exhaust valve housing, an additional coolant supply is required to generate a sufficient temperature difference across the thermoelectric generator. Providing an additional coolant supply may increase the cost and complexity of such a system. Furthermore, only a portion of the exhaust gas from the engine can flow through the exhaust valve, and only under certain operating conditions (such as high load conditions), thus Mitkari's system fails to utilize other waste heat sources in the exhaust system. Moreover, Mitkari failed to recognize that because the current generated by the thermoelectric generator is proportional to the temperature difference across it, the presence of thermoelectric generators in certain locations within the vehicle presents an opportunity to utilize them as sensors for monitoring the performance of a vehicle or engine component. Summary of the Invention

[0005] Therefore, the inventors of this paper provide a method that at least partially solves the aforementioned problems. In one example, a method includes adjusting one or more engine operating parameters based on the amount of current generated from one or more thermoelectric generators coupled to a turbocharger. In this way, the amount of current generated by the one or more thermoelectric generators can be monitored to determine whether a temperature difference across the thermoelectric generators corresponds to an expected temperature difference. In one example, because the thermoelectric generators are coupled to the turbocharger, the expected temperature difference can reflect the expected temperature of the turbocharger's turbine. If the amount of current generated by the one or more thermoelectric generators is greater than expected, a temperature reflecting a higher turbine temperature can be indicated, indicating a temperature difference greater than expected. In response to the higher turbine temperature, the exhaust valve position can be adjusted to direct hot exhaust gas away from the turbine and / or engine torque can be limited to reduce exhaust mass flow rate and temperature.

[0006] It should be understood that the above-described invention is presented in a simplified form as a selection of concepts further described in the detailed embodiments. This does not imply identification of the key or essential features of the claimed subject matter, the scope of which is uniquely defined by the claims following the detailed embodiments. Furthermore, the claimed subject matter is not limited to solutions to any of the shortcomings mentioned above or in any part of this disclosure. Attached Figure Description

[0007] Figure 1 An exemplary vehicle and vehicle engine system are schematically shown.

[0008] Figure 2 An exemplary thermoelectric generator (TEG) is schematically shown.

[0009] Figure 3 A first exemplary turbocharging system is schematically shown, in which the TEG is mounted on the exhaust turbine.

[0010] Figure 4 A second exemplary turbocharging system is schematically shown, in which the TEG is mounted on the exhaust turbine.

[0011] Figure 5 A third exemplary turbocharging system is schematically shown, in which the TEG is mounted on the exhaust turbine.

[0012] Figure 6 A fourth exemplary turbocharging system is schematically shown, in which the TEG is mounted on the entire exhaust turbine.

[0013] Figures 7A to 7B A flowchart illustrating a method for using a TEG to monitor the temperature of the exhaust turbine and / or compressor and to perform diagnostics on the turbine, compressor, electric supercharger, and / or exhaust valve.

[0014] Figure 8 This indicates that during execution Figures 7A to 7B The timing diagram shows the operating parameters that can be observed during the method shown. Detailed Implementation

[0015] The following description relates to systems and methods for thermoelectrically recovering waste heat from an exhaust turbine in a turbocharger system in a vehicle. The description also relates to systems and methods for monitoring and diagnosing the performance of an exhaust turbine, wastegate, compressor, and / or electric supercharger-assisted mechanical supercharger system using a thermoelectric generator mounted on the exhaust turbine. The use of a thermoelectric generator mounted on the exhaust turbine housing of a turbocharger system can be applied to vehicle systems (such as...) Figure 1 Implemented in the vehicle system shown in the figure. Figure 2 The image shows a thermoelectric generator (TEG). Figure 3 The image shows a first configuration of TEGs mounted on the exhaust turbine housing, with some TEGs in direct contact with the compressor and others in contact with ambient air. Figure 4 The image shows a second configuration of the TEG partially mounted around the exhaust turbine housing. Figure 5 The third configuration of the TEG is shown, with it mounted entirely around the exhaust turbine housing. Figure 6 The fourth configuration of the TEG, with additional heat-conducting fins, is shown, completely surrounding the exhaust turbine. Figures 7A to 7B The diagram illustrates methods for using TEG to monitor and diagnose exhaust turbines and wastegates, as well as methods for using TEG to monitor and diagnose compressors and electric superchargers. Figure 8 The timing diagram shows the execution Figures 7A to 7B The operating parameters that can be observed during the method.

[0016] Turn now Figure 1 An example of a cylinder 14 of an internal combustion engine 10 that may be included in a vehicle 5 is shown. The engine 10 may be controlled at least in part by a control system including a controller 12 and by input from a vehicle operator 130 via an input device 132. In this example, the input device 132 includes an accelerator pedal and a pedal position sensor 134 for generating a proportional pedal position signal PP. The cylinder 14 of the engine 10 (also referred to herein as a “combustion chamber”) may include a combustion chamber wall 136 in which a piston 138 is positioned. The piston 138 may be coupled to a crankshaft 140 such that the reciprocating motion of the piston is converted into rotational motion of the crankshaft. The crankshaft 140 may be coupled to at least one drive wheel 55 of the passenger vehicle via a transmission 54, as further described below. Additionally, a starter motor (not shown) may be coupled to the crankshaft 140 via a flywheel to enable starting operation of the engine 10.

[0017] In some examples, vehicle 5 may be a hybrid vehicle with multiple torque sources available to one or more wheels 55. In other examples, vehicle 5 is a conventional vehicle with only an internal combustion engine. In the example shown, vehicle 5 includes an engine 10 and an electric motor 52. The electric motor 52 may be a motor or a motor / generator. When one or more clutches 56 are engaged, the crankshaft 140 of engine 10 and the electric motor 52 are connected to the wheels 55 via a transmission 54. In the depicted example, a first clutch 56 is disposed between the crankshaft 140 and the electric motor 52, and a second clutch 56 is disposed between the electric motor 52 and the transmission 54. Controller 12 may send signals to the actuators of each clutch 56 to engage or disengage the clutch, thereby connecting or disconnecting the crankshaft 140 from the electric motor 52 and its connected components, and / or connecting or disconnecting the electric motor 52 from the transmission 54 and its connected components. The transmission 54 may be a gearbox, a planetary gear system, or another type of transmission. The powertrain may be configured in various ways, including as a parallel, series, or series-parallel hybrid vehicle.

[0018] Motor 52 receives power from traction battery 58 to provide torque to wheel 55. Motor 52 can also operate as a generator to provide power, for example, during braking operations, to charge battery 58.

[0019] Cylinder 14 of engine 10 receives intake air via a series of intake passages 142, 144, and 146. In addition to cylinder 14, intake passage 146 may also communicate with other cylinders of engine 10. In some examples, one or more of the intake passages may include a supercharging device, such as a turbocharger or a supercharger. For example, Figure 1 An engine 10 equipped with a turbocharger is shown, the turbocharger including a compressor 174 disposed between intake passages 142 and 144 and an exhaust turbine 176 disposed along an exhaust passage 148. When the supercharging device is configured as a turbocharger, the compressor 174 may be at least partially powered by the exhaust turbine 176 via a shaft 180. However, in other examples, such as when the engine 10 is equipped with a supercharger, the compressor 174 may be powered by mechanical input from a motor or engine, and the exhaust turbine 176 may optionally be omitted.

[0020] In another example, engine 10 may include a wastegate 175 that allows exhaust gas from the engine to bypass the exhaust turbine 176 and proceed to the emission control unit 178. The wastegate allows control of the maximum exhaust turbine speed, which mitigates the maximum boost pressure generated within the intake passage 144 by the compressor 174. The wastegate also protects the turbocharging system and the vehicle engine from unwanted wear because it allows for reduced temperature and turbine speed by bypassing engine exhaust gas.

[0021] In some examples, engine 10 includes an electric compressor 160, which defines a mechanical supercharger, or "electric supercharger," staged upstream of compressor 174. While other configurations are possible, the mechanical supercharger herein is an auxiliary supercharging device, and the turbocharger is the primary supercharging device. For example, in an alternative embodiment, the turbocharger may be an electric turbocharger having an electric motor coupled to the compressor, turbine, or turbocharger shaft, while the mechanical supercharger is configured as either an electric or mechanical supercharger. In other examples, both supercharging devices may be either an electric mechanical supercharger or an electric turbocharger.

[0022] The electric compressor 160 is driven by an electric motor 161 along the compressor shaft of the supercharger. The electric motor may be powered by an onboard energy storage device, such as battery 58. Alternatively, the electric motor 161 may be powered directly from one or more thermoelectric generators coupled to turbine 176, as will be described in more detail below. The electrical force delivered to the electric motor 161 can be varied to adjust the duty cycle of the supercharger. In one example, the electrical force delivered to the electric motor 161 can be increased to increase the rotational speed of the electric compressor 160. Thus, due to electric assistance, the supercharger can rapidly accelerate its rotation, providing rapid action or high-frequency boost actuation. During certain conditions (such as when the accelerator pedal is depressed), the electric motor 161 can be operated to rotate the electric compressor 160 in the forward direction to provide boost assistance.

[0023] A throttle valve 162, including a throttle plate 164, may be disposed in the engine intake passage to change the flow rate and / or pressure of the intake air supplied to the engine cylinders. For example, the throttle valve 162 may be located downstream of the compressor 174, such as... Figure 1 As shown; or alternatively, it can be located upstream of compressor 174.

[0024] In addition to cylinder 14, exhaust passage 148 may also receive exhaust gas from other cylinders of engine 10. Exhaust sensor 128 is shown coupled upstream of emission control device 178 to exhaust passage 148. Exhaust sensor 128 may be selected from various sensors suitable for providing exhaust air-fuel ratio (AFR) indication, such as, for example, a linear oxygen sensor or UEGO (universal or wide-range exhaust oxygen sensor), a dual-state exhaust oxygen sensor or EGO (as depicted), HEGO (heated EGO), NOx, HC, or CO sensors. Emission control device 178 may be a three-way catalytic converter, a NOx trap, various other emission control devices, or combinations thereof.

[0025] Each cylinder of engine 10 may include one or more intake valves and one or more exhaust valves. For example, cylinder 14 is shown as including at least one intake lift valve 150 and at least one exhaust lift valve 156 located in the upper region of cylinder 14. In some examples, each cylinder of engine 10 (including cylinder 14) may include at least two intake lift valves and at least two exhaust lift valves located in the upper region of the cylinder. Intake valve 150 may be controlled by controller 12 via actuator 152. Similarly, exhaust valve 156 may be controlled by controller 12 via actuator 154. The positions of intake valve 150 and exhaust valve 156 may be determined by corresponding valve position sensors (not shown).

[0026] In some cases, controller 12 may modify the signals provided to actuators 152 and 154 to control the opening and closing of the corresponding intake and exhaust valves. The valve actuators may be electrically actuated, cam-actuated, or a combination thereof. Intake and exhaust valve timing may be controlled via variable intake cam timing, variable exhaust cam timing, dual independent variable cam timing, or fixed cam timing. Each cam-actuated system may include one or more cams and may utilize one or more of a cam profile change (CPS), variable cam timing (VCT), variable valve timing (VVT), and / or variable valve lift (VVL) system operable by controller 12 to change valve operation. For example, cylinder 14 may alternatively include an intake valve controlled via electrically actuated control and an exhaust valve controlled via cam actuation (including CPS and / or VCT). In other examples, the intake and exhaust valves may be controlled by a common valve actuator (or actuation system) or a variable valve timing actuator (or actuation system).

[0027] Cylinder 14 may have a compression ratio, which is the ratio of the volume of piston 138 at bottom dead center (BDC) to the volume at top dead center (TDC). In one example, the compression ratio is in the range of 9:1 to 10:1. However, in some examples using different fuels, the compression ratio may be increased. This may occur, for example, when using fuels with higher octane ratings or fuels with higher possible enthalpy of vaporization. The compression ratio may also be increased if direct injection is used due to its effect on engine knock.

[0028] In some examples, each cylinder of engine 10 may include a spark plug 192 for initiating combustion. In a selected operating mode, ignition system 190 may provide an ignition spark to combustion chamber 14 via spark plug 192 in response to a spark advance signal SA from controller 12. The timing of signal SA may be adjusted based on engine operating conditions and driver torque demands. For example, a spark may be provided at maximum brake torque (MBT) timing to maximize engine power and efficiency. Controller 12 may input engine operating conditions (including engine speed, engine load, and exhaust AFR) into a lookup table and output the corresponding MBT timing for the input engine operating conditions. In other examples, the engine may ignite the charge via compression, as in a diesel engine.

[0029] In some examples, each cylinder of engine 10 may be configured with one or more fuel injectors for supplying fuel thereto. As a non-limiting example, cylinder 14 is shown including a fuel injector 166. Fuel injector 166 may be configured to deliver fuel received from fuel system 8. Fuel system 8 may include one or more fuel tanks, fuel pumps, and fuel rails. Fuel injector 166 is shown directly coupled to cylinder 14 to inject fuel directly into it in proportion to the pulse width of the signal FPW-1 received from controller 12 via electronic actuator 168. In this manner, fuel injector 166 provides so-called direct fuel injection into cylinder 14 (hereinafter also referred to as "DI"). Although Figure 1 A fuel injector 166 is shown positioned on one side of cylinder 14, but alternatively, the fuel injector 166 may be located on top of the piston, such as near spark plug 192. This location enhances mixing and combustion when the engine is operated with alcohol-based fuels due to the lower volatility of some alcohol-based fuels. Alternatively, the injector may be located on top of and near the intake valve to enhance mixing. Fuel may be delivered from the fuel tank of fuel system 8 to the fuel injector 166 via a high-pressure fuel pump and fuel rail. Additionally, the fuel tank may have a pressure transducer that provides a signal to controller 12.

[0030] In a configuration providing so-called port fuel injection (hereinafter referred to as "PFI") into the intake manifold upstream of cylinder 14, fuel injector 170 is shown arranged in intake passage 146 rather than in cylinder 14. Fuel injector 170 can inject fuel received from fuel system 8 in proportion to the pulse width of signal FPW-2 received from controller 12 via electronic actuator 171. It should be noted that a single actuator 168 or 171 may be used for both fuel injection systems, or multiple actuators may be used, such as the exemplary actuator 168 for fuel injector 166 and actuator 171 for fuel injector 170, as depicted.

[0031] In an alternative example, each of fuel injectors 166 and 170 may be configured as a direct fuel injector for injecting fuel directly into cylinder 14. In yet another example, each of fuel injectors 166 and 170 may be configured as a port fuel injector for injecting fuel upstream of intake valve 150. In still some examples, cylinder 14 may include only a single fuel injector configured to receive different fuels as a fuel mixture from the fuel system in different relative amounts, and further configured to either inject this fuel mixture directly into the cylinder as a direct fuel injector or inject this fuel mixture upstream of the intake valve as a port fuel injector.

[0032] During a single cycle of a cylinder, fuel may be delivered to the cylinder by two injectors. For example, each injector may deliver a portion of the total fuel injected for combustion in cylinder 14. Furthermore, the distribution and / or relative amount of fuel delivered from each injector may vary with operating conditions such as engine load, knock, and exhaust temperature, as described herein. Intake port injection fuel may be delivered during intake valve opening events, intake valve closing events (e.g., substantially before the intake stroke), and during both intake valve opening and closing operations. Similarly, for example, direct injection fuel may be delivered during the intake stroke, or partly during the preceding exhaust stroke, during the intake stroke, and partly during the compression stroke. Thus, even for a single combustion event, the injected fuel may be injected from the intake port injector and the direct injector at different timings. Additionally, for a single combustion event, multiple injections of the delivered fuel may be performed in each cycle. Multiple injections may be performed during the compression stroke, the intake stroke, or any suitable combination thereof.

[0033] Fuel injectors 166 and 170 may have different characteristics. These different characteristics include size differences; for example, one injector may have a larger injection orifice compared to the other. Other differences include, but are not limited to, different spray angles, different operating temperatures, different orientations, different injection timings, different spray characteristics, different positions, etc. Furthermore, different effects can be achieved depending on the fuel distribution ratio between injectors 170 and 166.

[0034] The fuel tank in fuel system 8 can hold fuels of different types, such as fuels with different fuel qualities and different fuel compositions. Differences may include different alcohol contents, different water contents, different octane numbers, different heats of vaporization, different fuel mixtures, and / or combinations thereof. One example of fuels with different heats of vaporization could be gasoline with a lower heat of vaporization as the primary fuel type and ethanol with a higher heat of vaporization as the secondary fuel type. In another example, the engine could use gasoline as the primary fuel type and an alcohol-containing fuel mixture (such as E85 (which is approximately 85% ethanol and 15% gasoline) or M85 (which is approximately 85% methanol and 15% gasoline)) as the secondary fuel type. Other feasible substances include water, methanol, mixtures of alcohol and water, mixtures of water and methanol, mixtures of alcohols, etc.

[0035] Controller 12 in Figure 1 The computer, shown as a microcomputer, includes: a microprocessor unit 106, an input / output port 108, an electronic storage medium for executable programs (e.g., executable instructions) and calibration values ​​(shown in this specific example as a non-transitory read-only memory chip 110), a random access memory 112, a keep-alive memory 114, and a data bus. The controller 12 can receive various signals from sensors coupled to the engine 10, including those previously discussed, and additionally including: the measured mass airflow (MAF) from the mass airflow sensor 122; the engine coolant temperature (ECT) from the temperature sensor 116 coupled to the cooling sleeve 118; the exhaust temperature from the temperature sensor 158 coupled to the exhaust passage 148; the surface ignition sensing signal (PIP) from the Hall effect sensor 120 (or other type of sensor) coupled to the crankshaft 140; the throttle position (TP) from the throttle position sensor; the signal EGO from the exhaust sensor 128, which can be used by the controller 12 to determine the exhaust airflow rate (AFR); and the absolute manifold pressure signal (MAP) from the MAP sensor 124. The engine speed signal RPM can be generated by the controller 12 based on the signal PIP. The manifold pressure signal MAP from the MAP sensor 124 can be used to provide an indication of vacuum or pressure in the intake manifold. The controller 12 can infer the engine temperature based on the engine coolant temperature and infer the temperature of the catalyst 178 based on the signal received from the temperature sensor 158.

[0036] Controller 12 from Figure 1 Various sensors receive signals, and based on the received signals and instructions stored in the controller's memory, employ... Figure 1Various actuators are used to adjust engine operation. For example, once the engine controller receives signals from various sensors, it can send control signals to the actuators to adjust the position of the exhaust valve 175, activate the electric supercharger 160, or perform other appropriate actions.

[0037] As described above, Figure 1 Only one cylinder of a multi-cylinder engine is shown. Thus, each cylinder can similarly include its own set of intake / exhaust valves, one or more fuel injectors, spark plugs, etc. It should be understood that engine 10 can include any suitable number of cylinders (including 2, 3, 4, 5, 6, 8, 10, 12, or more cylinders). Furthermore, each of these cylinders can include... Figure 1 Some or all of the various components described and depicted with reference to cylinder 14.

[0038] Now for reference Figure 2 The diagram illustrates a schematic of a thermoelectric generator (TEG) 200. The TEG utilizes the Seebeck effect (a form of thermoelectric effect) to generate electrical energy from a temperature difference. The TEG may include a hot-side insulation layer 216 and a cold-side insulation layer 218, with the hot-side insulation layer 216 acting as a hot-side heat exchanger and the cold-side insulation layer 218 acting as a cold-side heat exchanger. Thermoelectric materials such as n-doped semiconductors 202 and p-doped semiconductors 204 may be sandwiched between the hot-side 216 and the cold-side 218. In one example, the TEG 200 may also include a compression assembly system that holds the TEG 200 together. The temperature difference between the hot-side 216 and the cold-side 218 generates a potential (e.g., a voltage) in the thermoelectric material. The amount of voltage generated by the TEG corresponds to the temperature difference between the hot-side 216 and the cold-side 218; a relatively large temperature difference between the hot-side 216 and the cold-side 218 results in the generation of a relatively large amount of electrical energy. In this example, the thermoelectric material comprises alternating series-connected n-doped semiconductors 202 and p-doped semiconductors 204, such that a voltage across the thermoelectric material is added to generate a larger voltage between the negative terminal 210 and the positive terminal 212 of the TEG. One or more components, sensors, and / or batteries 214 can then be connected across terminals 210, 212 to power one or more components and / or charge the battery 214. In one example, the electric motor 161 of the electric compressor 160 of the upstream supercharger can be partially or fully powered by the TEG based on electricity generated from waste heat recovered from the TEG on the exhaust casing. In this example, a switch may be provided at the junction between the conduit coupling one or more TEGs to the battery and the conduit coupling to the electric motor, or at another suitable location. The switch can be adjusted to allow all current from the TEG to flow to the battery, or to allow some or all of the current from the TEG to flow to the electric motor. It should be understood that a switch not provided in the TEG may be available. Figure 2 Other circuits shown in the diagram.

[0039] A current sensor 220 may be included in the TEG circuit to monitor the current generated by the TEG. The engine controller 12 can use the current sensor measurement to determine the power generated by the TEG and calculate the temperature difference across the TEG. In one example, doped lead telluride (PbTe) can be used as a p-type semiconductor 204, and bismuth telluride (Bi2Te3) can be used as an n-type semiconductor 202. In other examples, other thermoelectric materials, such as Bi2Se3Sb2Te3 or other bismuth chalcogenides, inorganic inclusion compounds (Ba8Ga), can be used. 16 Ge 30 Ba8Ga 16 Si 30 Magnesium Group IV compounds (Mg2Si, Mg2Ge, Mg2Sn), silicides, cobaltite thermoelectric materials, oxide thermoelectric materials, semi-Hassler alloys, silicon germanium, sodium cobaltate, tin selenide, and others.

[0040] In addition to being a generator, the TEG 200 can also be used as a temperature sensor. Because the voltage and current generated by the TEG correspond to the temperature difference between the hot side 216 and the cold side 218, the current measured by the current sensor 220 can be correlated with the temperature difference across the TEG, and in some examples, if the temperature of other components is known or estimated (e.g., by using other temperature sensors associated with the engine 10, such as exhaust manifold sensor 158), it can be correlated with the temperature of one of the components coupled to the TEG (e.g., the compressor or turbine). This allows the TEG to be used for temperature monitoring and diagnostics in turbocharger and electric supercharger systems, in addition to its use for waste heat recovery.

[0041] Now go to Figure 3 The illustration shows an exemplary turbocharger system 300 having a compressor 174, an intake passage 142, a connecting shaft 180, an exhaust turbine 176, an exhaust turbine heat shield 302, a turbine impeller 308, and multiple TEGs 304 mounted to the heat shield. After combustion, exhaust gas enters the exhaust turbine 176 from the exhaust passage 148 and rotates the turbine impeller 308, which in turn rotates the shaft 180 and the compressor impeller 306 to power the compressor 174. Fresh air (and EGR, fuel vapor, or other gases, depending on the engine configuration) enters the compressor 174 from the intake passage 142 before being compressed via the impeller 306 and is directed to the intake passage 146 and cylinder 14 for fuel combustion. The heat shield 302 may be constructed of a suitable insulating material, such as metal, silica, ceramic, or other materials. The heat shield 302 may extend around the turbine 176 as shown, or may have another suitable shape, such as conforming to the shape of the turbine housing. In addition, in some examples, the heat shield 302 can be omitted, and multiple TEGs can be directly coupled to the turbine housing.

[0042] The TEG 304 can be installed between the compressor 174 and the exhaust turbine 176, with the hot side 216 of the TEG contacting the heat shield 302. The cold side 218 of the TEG can contact the compressor 174 or ambient air (e.g., engine hood air). Figure 3 In the configuration shown, each TEG is coupled to the inner wall of the heat shield 302 facing the compressor. The inner wall of the heat shield can represent the portion of the heat shield closest to the compressor. The remaining portions of the heat shield away from the heat shield (such as the top wall, bottom wall, etc.) may not include any TEGs.

[0043] Figure 3 Each TEG shown can be Figure 2 The TEG 200 is a non-limiting example. Therefore, each TEG 304 may include at least one n-doped and p-doped semiconductor pair that is series-coupled and electrically coupled to a component such as a battery. Furthermore, each TEG 304 may be coupled to a separate current sensor, a subset of the TEGs may be coupled to a common current sensor, or all TEGs may be coupled to a single current sensor. As shown, a subset of the TEGs is directly coupled (e.g., in face-sharing contact) to both the turbine (e.g., heat shield) and the compressor (e.g., compressor housing), and the remaining TEGs are directly coupled to the turbine on the hot side and open to the environment on the cold side. However, other configurations are also possible, such as all TEGs being directly coupled to both the turbine and the compressor, or all TEGs being coupled only to the turbine.

[0044] Figure 3 Nine individual TEG modules are shown. However, Figure 3 The TEG modules shown are exemplary, and other configurations are possible. For example, other numbers of TEG modules (such as four, six, or other suitable numbers) may be coupled to the heat shield. In other examples, only one TEG module may be coupled to the heat shield, but the TEG modules may extend across a larger area of ​​the heat shield's surface (e.g., Figure 3 Two or more of the individual modules shown can be combined into a larger single module. It should be understood that the TEG is shown in cross-section and the TEG can be along... Figure 3 Other axial extensions not shown. The TEG can be of a suitable size based on turbine size, packaging constraints, etc. The TEG can be mounted as a separate structure on the heat shield. In other examples, the TEG can be integrally formed with the heat shield.

[0045] During vehicle operation, the exhaust turbine housing can reach temperatures between 750°C and 800°C, while the engine hood air and compressor can reach temperatures around 100°C. Additionally, during vehicle operation, the compressor 174 receives cooler fresh air, which helps maintain a lower temperature relative to the exhaust turbine 176. The TEG (Transmission Electro-Governing Unit) positioned between the compressor and exhaust turbine during vehicle operation, allowing for a minimum temperature difference of 650°C, maximizes the recovery of waste heat as electrical energy and allows for the measurement of the temperature difference between the compressor and exhaust turbine for monitoring and diagnostics of turbocharger and electric supercharger systems.

[0046] Now go to Figure 4 Another illustration shows an exemplary turbocharging system 400 having a compressor 174, an intake passage 142, a connecting shaft 180, an exhaust turbine 176, a heat shield 302, a turbine rotor 308, a compressor impeller 306, and multiple TEGs 402 mounted to the heat shield. Figure 3 Compared to the turbocharger system in this configuration, the cold side 218 of each TEG mounted on the heat shield 302 is in contact with ambient air (e.g., engine hood air). Furthermore, the TEG is arranged on the heat shield such that it partially extends along the turbine housing. For example, as shown, a first portion of the TEG is positioned on the inner wall of the heat shield between the turbine and the compressor, a second portion of the TEG is positioned along the top wall of the heat shield, and a third portion of the TEG is positioned along the bottom wall of the heat shield. The TEG positioned on the top and bottom walls of the heat shield may only cover a portion of the top and bottom walls. For example, only 50% of the length of the top wall of the heat shield may include the TEG. The portion of the heat shield extending along the turbine inlet 404 and turbine outlet 406 may not include... Figure 4 The TEG shown in the example. Additionally, one or more TEGs may be arranged along the turbine housing around shaft 180.

[0047] Figure 5 Another illustration shows an exemplary turbocharging system 500 having a compressor 174, an intake passage 142, a connecting shaft 180, an exhaust turbine 176, a heat shield 302, a compressor impeller 306, a turbine rotor 308, and multiple TEGs 502 mounted on the heat shield. Figures 3 to 4 Compared to the turbocharger system, the TEG extends across the entire heat shield 302 (including the portion of the heat shield that extends above / around the turbine inlet and outlet).

[0048] Figure 6Additional illustrations show an exemplary turbocharging system 600 having a compressor 174, an intake passage 142, a connecting shaft 180, an exhaust turbine 176, a heat shield 302, a compressor impeller 306, a turbine rotor 308, and multiple TEGs 602 mounted on the heat shield, wherein each TEG includes one or more heat sinks 604. Figures 3 to 5 Compared to the turbocharged system, the TEG cold side 218 has a fixed heat-conducting fin 604, which acts as a radiator by transferring heat to the lower-temperature engine hood air through an increased surface area. Using the heat-conducting fin as an additional passive cooling mechanism for the TEG cold side ensures that the maximum temperature difference between the TEG hot side 216 and the TEG cold side 218 is maintained.

[0049] In addition to or in place of the heat-conducting fins 604, an additional cooling mechanism may be used with the TEG cold side 218 to maintain a maximum temperature difference in order to extract waste heat and generate electrical energy. In one example, a water cooling system (not shown) may circulate coolant between the TEG cold side 218 and the radiator (not shown). The water cooling system for the TEG may be a dedicated system or part of the main coolant system for the vehicle engine 10.

[0050] therefore, Figures 3 to 6 Various examples of turbochargers including one or more TEGs coupled thereto are shown. In the examples shown, one or more TEGs may be coupled to a heat shield surrounding the turbine. However, in other examples, one or more TEGs may be coupled to the turbine housing or other suitable components. Based on the turbocharger configuration and current power generation needs (e.g., the amount of current the TEGs will generate), one or more TEGs may be positioned appropriately on the turbine. For example, the region of the turbocharger between the turbine and the compressor housing (e.g., around the turbocharger shaft) may experience the highest temperature difference of any region of the turbocharger. Therefore, as Figure 3 As shown, one or more TEGs may be positioned on the inner wall of the heat shield, wherein the inner wall faces the compressor and is adjacent to and / or at least partially surrounds the turbocharger shaft. TEGs positioned along the inner wall may make face-shared contact with the inner wall along the hot side of each TEG, and optionally may make face-shared contact with compressor components (such as the compressor housing) along the cold side of each TEG. In other examples, additional TEGs may be positioned along the top, bottom, and / or other areas of the heat shield or turbine housing. The selection of areas of the heat shield or turbine housing includes: the TEGs may be based on the turbocharger packaging, cost, and temperature differences at each location.

[0051] See now Figure 7AThis paper illustrates a method 700 for monitoring turbocharger performance using the amount of current generated by one or more TEGs coupled to the turbocharger. Method 700 can be used in engine systems (such as...) Figure 1 This is performed within a system, so as to be based on one or more TEGs (such as...). Figure 2 The current generated by the TEG 200 monitors the performance of turbochargers such as turbine 176 and compressor 174, exhaust valves such as exhaust valve 175, and / or electric superchargers such as electric compressor 160. Instructions for performing method 700 and the remaining methods included herein can be generated by a controller (such as...) Figure 1 The controller 12) is based on instructions stored in the controller's memory and in conjunction with information from sensors in the engine system (such as those mentioned above). Figure 2 The controller uses the signal received by the current sensor (described below) to perform the operation. According to the method described below, the controller can employ the engine actuator of the engine system to adjust engine operation.

[0052] At 702, method 700 determines operating parameters. Operating parameters may include current vehicle speed, engine speed, engine coolant temperature, engine running time, exhaust temperature, and / or other operating parameters. At 704, method 700 determines whether conditions for monitoring the exhaust turbine of the turbocharger system are met. Conditions for monitoring the exhaust turbine may include an engine coolant temperature greater than a threshold temperature (e.g., such that the engine temperature, and therefore the exhaust temperature, is high enough to generate a sufficient temperature difference between the compressor and the turbine for generating current via the TEG), a time since engine start-up greater than a threshold time (which may also act as a proxy for indicating that the turbine temperature is high enough to generate current via the TEG), an exhaust temperature greater than a threshold, and / or engine speed and / or load greater than a threshold. In some examples, turbine monitoring may be performed only after a threshold duration (whether time or mileage) has elapsed since previous turbine monitoring was performed. In a further example, turbine monitoring may be performed in response to an indication that exhaust valve position sensor data and / or exhaust temperature data are unavailable. For example, if the exhaust valve position cannot be determined from the exhaust valve position sensor data (e.g., due to sensor degradation), the exhaust valve function can be monitored based on the amount of current generated by the TEG. If the conditions for monitoring the exhaust turbine are met, the answer is yes, and method 700 proceeds to 708. Otherwise, the answer is no, and method 700 proceeds to 705.

[0053] At 705, method 700 determines whether conditions for monitoring compressor 174 of the turbocharger system are met. Conditions for monitoring the compressor may include the same conditions discussed above for monitoring the turbocharger (e.g., sufficient exhaust temperature to allow current to be generated by the TEG). Additionally, in some examples, conditions for monitoring the compressor may additionally or alternatively include an ambient air temperature below a threshold temperature (e.g., less than 100℉) such that the compressor and / or engine hood are sufficiently cold to allow sufficient current to be generated by the TEG. Additionally or alternatively, the compressor may be monitored in response to an indication that intake air temperature data (or other intake system data, such as compressor recirculation valve position data) is unavailable. Figure 7A The illustration shows compressor monitoring performed only in response to the failure of conditions for monitoring the turbine. It should be understood that in some examples, compressor monitoring may be performed independently of turbine monitoring (e.g., independent of whether conditions for monitoring the turbine are met at 704) and / or turbine monitoring and compressor monitoring may be performed simultaneously.

[0054] If the conditions for monitoring compressor 174 are met, the answer is yes, and method 700 proceeds to 724. Figure 7B (As shown in the diagram). Otherwise, the answer is no, and method 700 proceeds to 706. At 706, method 700 maintains the vehicle's current operating parameters. Maintaining the current operating parameters may include: allowing exhaust flow through the turbine and compressing fresh air via the compressor, adjusting the position of the cross-turbine coupled wastegate based on exhaust mass flow rate, exhaust or turbine temperature, and / or engine load, and activating the electric supercharger (e.g., electric supercharger 160) to provide torque assistance as commanded. The current operating parameters may also include: utilizing the TEG to generate current via the temperature difference across the TEG, and allowing the current to flow to the battery for storage and / or for driving the electric supercharger. Method 700 returns.

[0055] At point 708, method 700 measures the current generated by the TEG mounted on the exhaust turbine heat shield or housing. The current is measured by a current sensor (such as...) Figure 2 The sensor 200 in the TEG measures the current, and the measured current value is sent to the controller. The measured current can be the current generated by each individual TEG, the current generated by a cluster of several TEGs, or the total current from each TEG on the exhaust turbine.

[0056] At 710, method 700 determines whether to command a change in the wastegate position. The wastegate position can be commanded to change under high engine load when the engine produces more exhaust and the wastegate is open to allow excess exhaust to bypass the exhaust turbine. In other examples, the wastegate can be commanded to close if the exhaust mass flow rate decreases and / or if increased boost pressure is needed when the wastegate is open. If the wastegate position is commanded to change, the answer is yes, and method 700 proceeds to 714. Otherwise, the answer is no, and method 700 proceeds to 712.

[0057] At 712, method 700 continues to monitor the temperature and performance of the exhaust turbine via the generated TEG current. The temperature and performance of the exhaust turbine can be determined from the measured TEG current by comparing it with a predetermined current meter for the exhaust turbine, taking into account the current engine parameters. Relevant engine parameters may include exhaust and intake air flow rates, engine coolant temperature, exhaust temperature, and / or compressor temperature. If the measured TEG current is within a predetermined tolerance of the expected predetermined current (taking into account engine parameters), the exhaust turbine is determined to be functioning. Otherwise, if a difference is observed between the expected and measured TEG currents, there may be potential deterioration of the exhaust turbine (e.g., the exhaust valve) and / or one or more TEGs, and the driver may be notified.

[0058] In other examples, turbine temperature can be monitored via current generated by one or more TEGs. If turbine temperature exceeds a threshold, the exhaust valve can be commanded to open to bypass exhaust around the turbine and prevent overheating events that could lead to turbine degradation. To monitor turbine temperature, the amount of current generated by one or more TEGs can be measured, and an estimated compressor and / or hood temperature can be determined. Because the generated current is proportional to the temperature difference, the temperature difference across the TEGs can be determined based on the amount of current generated by the TEGs. The estimated compressor and / or hood temperature can then be subtracted from the temperature difference to calculate the turbine temperature. In other examples, an upper limit current generated by the TEGs can be calculated based on the estimated compressor and / or hood temperature. The upper limit current reflects the permissible difference between the compressor and / or hood temperature and the turbine temperature. If the current generated by one or more TEGs exceeds the upper limit, the turbine can be indicated as being at a high temperature that could lead to degradation, and the exhaust valve can be commanded to open. Compressor temperature can be estimated based on intake mass flow rate, boost pressure, ambient air temperature, and / or other parameters. The engine hood temperature can be determined based on the output from a temperature sensor positioned to measure the engine hood temperature, or it can be estimated based on engine temperature, ambient air temperature, vehicle speed, and / or other parameters. Method 700 returns.

[0059] At 714, method 700 measures the current after commanding a change in the wastegate position. Method 700 then proceeds to 716, where it determines whether the expected change in current was observed after commanding a change in the wastegate position (e.g., when the wastegate position was changed). If the wastegate is commanded to open after being closed, less exhaust gas reaches the exhaust turbine, which may cause the exhaust turbine to rotate more slowly and the temperature to decrease, thus the TEG may generate less current. Conversely, if the wastegate is commanded to close after being open, more exhaust gas reaches the exhaust turbine, which may cause the exhaust turbine to rotate more quickly and the temperature to increase, thus the TEG may generate more current. If the expected change in the TEG current is observed within a predetermined tolerance, the answer is yes, and method 700 proceeds to 720. Otherwise, the answer is no, and method 700 proceeds to 718.

[0060] At 718, method 700 indicates the possible presence of exhaust valve deterioration. Method 700 then proceeds to 722, where the vehicle driver is notified of the potential exhaust valve deterioration. The driver can be notified via a setting code that causes the "Check Engine" light or a visual / audio alarm. Additionally, diagnostic codes can be set. Engine operating parameters can also be adjusted to compensate for potential exhaust valve deterioration. Adjustable operating parameters may allow the engine to operate in a lower power mode (e.g., limiting engine torque) and produce less exhaust, such as delaying intake valve timing, limiting throttle opening, limiting fuel injection quantity, etc. Method 700 returns.

[0061] Because the expected change in TEG current at 716 is observed to be within the predetermined tolerance, at 720, method 700 determines that the exhaust valve is functioning as expected. For example, if the exhaust valve is commanded to open from the fully closed position, the turbine temperature may decrease, and therefore the amount of current generated by the TEG may decrease. If the amount of current does indeed decrease, it can be determined that the exhaust valve is functioning. Method 700 returns.

[0062] In some examples, the current sensor may be positioned to measure the total current generated by all TEGs mounted to the turbocharger. However, in other examples, the current sensor may be positioned to measure the current generated only by one or a subset of the TEGs mounted to the turbocharger. For example, the current sensor may be positioned to measure only the current generated by one or more TEGs mounted in locations where the temperature is stable, consistent, and / or easily estimated or measured, such as the compressor or engine hood. In this way, differences in the current generated by the TEGs during vehicle operation can be more consistently attributed to variations in turbocharger temperature, thus increasing the robustness of turbocharger monitoring.

[0063] Now go to Figure 7BMethod 700 continues from 705 to 724. At 724, method 700 measures the current generated by the TEG installed between the compressor and the exhaust turbine. The current is measured by current sensor 220, and the measured current value is sent to controller 12. The measured current can be the current generated by each individual TEG, the current generated by a cluster of several TEGs, or the total current from each TEG between the compressor and the exhaust turbine housing.

[0064] At 726, method 700 determines whether to command the electric supercharger to operate. When more engine power is needed, the electric supercharger can be commanded to operate under high engine load, and the controller can send a command to activate an auxiliary electric supercharger (e.g., electric supercharger 160 driven by motor 161) to assist the compressor in compressing additional intake air, which is then provided to the cylinders for fuel combustion. If the electric supercharger is commanded to operate, the answer is yes, and method 700 proceeds to 730. Otherwise, the answer is no, and method 700 proceeds to 728.

[0065] At 728, method 700 continues to monitor compressor temperature and performance via the generated TEG current between the exhaust turbine and the compressor. The compressor temperature and performance can be determined from the measured TEG current by comparing it with a predetermined current meter of the TEG between the compressor and the exhaust turbine, taking into account current engine parameters. Relevant engine parameters may include exhaust and intake air flow rates, engine coolant temperature, intake air temperature, and / or exhaust turbine temperature. If the measured TEG current is within a predetermined tolerance of the expected predetermined current (taking into account engine parameters), the compressor is determined to be functioning. Otherwise, if a difference is observed between the expected and measured TEG currents, there may be a possible deterioration of the compressor and / or one or more TEGs, and the driver may be notified. For example, if the compressor temperature is consistently higher than expected, it can be determined that the compressor recirculation valve is stuck in the open position, causing compressed air to recirculate through the compressor, which may cause the compressor temperature to rise. Additional contributors to the increased compressor temperature may include excessive low-pressure EGR supplied to the intake port upstream of the compressor, which may cause the compressor temperature to be higher than expected.

[0066] In other examples, the compressor temperature can be monitored via current generated by one or more TEGs. If the compressor temperature exceeds a threshold, one or more operating parameters can be adjusted to compensate for the compressor temperature. For example, a booster air cooler downstream of the compressor may include a bypass valve configured to bypass intake air around the booster air cooler, thereby preventing the booster air from becoming too cold and / or preventing condensation buildup in the booster air cooler. If the compressor temperature exceeds the threshold, the bypass valve of the booster air cooler can be commanded to close to ensure all intake air passes through the booster air cooler. In other examples, the compressor temperature can be monitored to determine if condensation buildup in the booster air cooler is possible. For example, if the compressor temperature is relatively low (e.g., below a second threshold), the bypass valve can be opened to bypass at least some of the air around the booster air cooler.

[0067] To monitor the compressor temperature, the amount of current generated by one or more TEGs can be measured, and an estimated turbine temperature can be determined. Because the generated current is proportional to the temperature difference, the temperature difference across the TEGs can be determined based on the amount of current generated. The estimated turbine temperature can then be subtracted from the temperature difference to calculate the compressor temperature. The turbine temperature can be measured from a temperature sensor, or it can be estimated based on engine load, exhaust mass flow rate, air-fuel ratio, turbine speed, and / or other parameters.

[0068] As described above, the current sensor can be positioned to measure the total current generated by all TEGs mounted to the turbocharger. However, in other examples, the current sensor can be positioned to measure the current generated only by one or a subset of the TEGs mounted to the turbocharger. For example, the current sensor can be positioned to measure only the current generated by one or more of the TEGs in direct contact with the compressor housing. In this way, differences in the current generated by the TEGs during vehicle operation can be more consistently attributed to changes in compressor temperature, thereby increasing the robustness of compressor monitoring. Method 700 returns.

[0069] At 730, method 700 measures the current after commanding the electric supercharger to operate. At 732, method 700 determines whether the expected change in current was observed after commanding the electric supercharger to operate. If the electric supercharger is commanded to operate, more air is compressed in the intake passage and subsequently in the compressor, which may cause the compressor temperature to rise, thereby reducing the temperature difference between the compressor and the exhaust turbine and decreasing the measured TEG current. If the expected change in TEG current is observed within a predetermined tolerance, the answer is yes, and method 700 proceeds to 736. Otherwise, the answer is no, and method 700 proceeds to 734.

[0070] At 734, method 700 indicates the possible deterioration of the electric supercharger. For example, if the electric supercharger deteriorates and therefore does not operate when commanded to operate, or if the electric supercharger operates but at a load lower than commanded to operate, the compressor temperature may remain relatively stable and the generated current may not change. Therefore, deterioration of the electric supercharger can be indicated. Method 700 proceeds to 738, where the vehicle driver is notified of the possible deterioration of the electric supercharger. The vehicle driver can be notified via a setting code that causes the "Check Engine" light or visual / audio alarm to sound. Additionally, a diagnostic code indicating electric supercharger deterioration can be set. Engine operating parameters can also be adjusted to compensate for possible electric supercharger deterioration, such as limiting engine torque. Method 700 returns.

[0071] Because the expected change in TEG current at 732 is observed to be within a predetermined tolerance, at 736, method 700 includes indicating that the electric supercharger is functioning as expected. For example, when the electric supercharger is commanded to operate, it may operate under the commanded load, which could cause the compressor temperature to rise. The rise in compressor temperature can reduce the temperature difference across the TEG, resulting in a decrease in the amount of current generated by the TEG. Therefore, if the amount of current generated by one or more TEGs decreases when the electric supercharger is commanded to operate, the electric supercharger can be indicated as functioning. Method 700 returns.

[0072] Figure 8 This is a timing diagram 800 showing exemplary operating parameters observable during execution of method 700. The first graph, starting from the top, shows the engine load as indicated by curve 802. The second graph, starting from the top, shows the commanded exhaust valve position as indicated by curve 804. The third graph, starting from the top, shows the estimated or measured turbine temperature as indicated by curve 806. The fourth graph shows the estimated or measured compressor temperature as indicated by curve 808. The fifth graph shows the TEG current measured by a current sensor as indicated by curve 810. The expected TEG current is shown by dashed line 812. Time is plotted along the x-axis. The corresponding value for each operating parameter is shown on the y-axis, increasing from minimum to maximum. Exhaust valve position is shown as fully open or fully closed. Each graph is time-aligned, and significant time points are depicted by dashed lines and labeled t1-t5.

[0073] Before time t1, the engine load is relatively low (e.g., 30% of maximum rated load) and stable. Both turbine and compressor temperatures are stable. There is a sufficient temperature difference between the turbine and compressor, so current is generated by one or more TEGs. From time t1 to time t2, the engine load increases. The increased engine load leads to an increase in exhaust mass flow rate. Furthermore, the exhaust temperature rises, causing the turbine temperature to rise while the compressor temperature remains relatively stable. Therefore, the amount of current generated by the TEGs also increases between t1 and t2.

[0074] At t2, due to high engine load (possibly 90% of maximum load), the wastegate is commanded to open to bypass exhaust around the turbine. Between t2 and t3, the engine load remains high and the wastegate is commanded to open. However, at... Figure 8 In the example shown, the wastegate is stuck in the closed position, so it remains closed even when commanded to open. From t2 to t3, the compressor temperature remains stable while the turbine temperature continues to rise. Therefore, the TEG current continues to increase. Similarly, between t3 and t4, the engine load is high and the wastegate is still commanded to open (although it cannot open). Therefore, the turbine temperature does not decrease between t3 and t4, and the TEG current remains relatively high. Conversely, as shown by dashed line 812, if the wastegate could open as commanded, the turbine temperature could be expected to begin to decrease by time t3, resulting in a reduction in the TEG current.

[0075] At t4, the current generated by the TEG can be compared to the threshold current. The threshold current can be the current before the exhaust valve is commanded to open, such as the current at t2. (The last sentence appears to be incomplete and possibly refers to a different point.) Figure 8 It is understood that the current at t4 is equal to the current at t2. Therefore, the exhaust valve can be indicated as deteriorating (e.g., stuck in the closed position) because the change in current is not as expected. The expected change in current can be shown by line 812; for example, at t4, the expected current (if the exhaust valve can open) is less than the current at t2.

[0076] In response to the detection of exhaust valve degradation, the exhaust valve can be maintained in the closed position, limiting engine torque to reduce exhaust mass flow. As a result, engine load decreases between t4 and t5, and turbine temperature begins to decrease. Additionally, other parameters can be adjusted to reduce turbine temperature, such as preventing or limiting rich-air-fuel ratio shift.

[0077] As from Figure 8 It is understood that turbine performance / exhaust valve function can be determined after a commanded change in exhaust valve position. Because the turbine can retain heat for extended periods, this can be done only after the exhaust valve has been commanded to open for a threshold amount of time (e.g., after...). Figure 8The current is measured after a time delay from t3 to t4 (as shown in the figure) to allow the time for turbine temperature to vary with the exhaust valve position.

[0078] Therefore, the systems and methods disclosed herein provide one or more thermoelectric generator modules (TEGs) for mounting to a turbocharger. One or more TEGs may be mounted to a heat shield surrounding the turbine, or the TEGs may be mounted directly to the turbine housing. Furthermore, one or more of the TEGs may also be mounted directly (e.g., on opposite sides) to the turbocharger compressor. In this way, the TEGs can utilize waste heat from exhaust gas (combined with the cooler compressor and the environment surrounding the vehicle's engine hood) to generate electricity that can be stored in a battery. The battery can then power vehicle electrical loads such as AC compressors, coolant pumps, etc., or the battery can be configured to power the vehicle in an electric or hybrid configuration. In other examples, the electricity generated from the TEGs may be fed directly (e.g., without through a battery) to an electric supercharger (also called an electric compressor) to provide additional compression / torque assistance to the engine.

[0079] A typical turbocharger for automotive applications may include a turbine housing with dimensions ranging from approximately 48.3 cm × 6.4 cm (outer circumference x inner width) to 66 cm × 9.5 cm, resulting in a usable surface area of ​​300-620 cm² for energy generation. 2 The appropriate area. A 41cm 2 The TEG module can generate up to 12.3W of power, thus allowing for the arrangement of 7 to 15 modules in terms of size and generating over 184W of power. The potential is reusable, enabling the use of Joule circuitry to power the battery. Furthermore, the methods described herein may be advantageous when applied to twin-turbo or dual-turbocharger configurations with two turbines (and in some configurations, two compressors), as the additional hot-side surface area can be fitted with the TEG, potentially doubling the amount of electricity that can be generated relative to a single turbocharger configuration.

[0080] The technical advantage of mounting one or more thermoelectric generators (TEGs) to a turbocharger is that waste heat energy can be used to generate electricity. One or more turbocharger covers including a TEG will be able to support the charging of battery systems used in standard and hybrid vehicles. The TEG module is easy to package, can be adopted in different shapes depending on packaging needs, and requires no moving parts, thus ensuring a long service life for the cover. Furthermore, due to the heat insulation properties of the cover and the TEG, the engine operating point is unaffected by the use of the TEG, and turbo lag is expected to be reduced. Additionally, the cover of this invention does not include a separate cooling mechanism, thus revealing lower complexity.

[0081] One example provides a method comprising: adjusting one or more engine operating parameters based on the amount of current generated from one or more thermoelectric generators coupled to a turbocharger. In a first example of the method, adjusting the one or more engine operating parameters based on the amount of current generated from the one or more thermoelectric generators includes: adjusting an engine torque limit based on the amount of current generated from the one or more thermoelectric generators. In a second example of the method, which optionally includes the first example, adjusting the engine torque limit based on the amount of current generated from the one or more thermoelectric generators includes: indicating a degradation of a turbine-coupled exhaust valve across the turbocharger based on the amount of current generated from the one or more thermoelectric generators, and adjusting the engine torque limit in response to the indication. In a third example of the method, optionally including one or both of the first and second examples, indicating the deterioration of the turbine-coupled exhaust valve across the turbocharger based on the amount of current generated from the one or more thermoelectric generators includes: measuring a first amount of current generated from the one or more thermoelectric generators when the exhaust valve is commanded to a first position; measuring a second amount of current generated from the one or more thermoelectric generators when the exhaust valve is commanded to a second position; and indicating the deterioration of the exhaust valve in response to the first amount of current being within a threshold range of the second amount of current. In a fourth example of the method, optionally including one or more or each of the first to third examples, adjusting the engine torque limit based on the amount of current generated from the one or more thermoelectric generators includes: indicating the deterioration of the electric supercharger coupled upstream of the compressor of the turbocharger based on the amount of current generated from the one or more thermoelectric generators, and adjusting the engine torque limit in response to the indication. In a fifth example of the method, optionally including one or more or each of the first to fourth examples, indicating degradation of the electric supercharger based on the amount of current generated from the one or more thermoelectric generators includes: measuring a first amount of current generated from the one or more thermoelectric generators when the electric supercharger is deactivated; measuring a second amount of current generated from the one or more thermoelectric generators when the electric supercharger is commanded to operate under a given load; and indicating degradation of the electric supercharger in response to the first amount of current being within a threshold range of the second amount of current. In a sixth example of the method, optionally including one or more or each of the first to fifth examples, adjusting one or more engine operating parameters based on the amount of current generated from the one or more thermoelectric generators includes: adjusting the position of the turbine-coupled exhaust valve across the turbocharger based on the amount of current generated by the one or more thermoelectric generators.In a seventh example of the method, optionally including one or more or each of the first to sixth examples, adjusting the position of the turbine-coupled exhaust valve across the turbocharger based on the amount of current generated by the one or more thermoelectric generators includes: opening the exhaust valve in response to the amount of current generated by the one or more thermoelectric generators exceeding a threshold amount. In an eighth example of the method, optionally including one or more or each of the first to seventh examples, the method further includes causing the current generated by the one or more thermoelectric generators to flow to a battery.

[0082] One example provides a system comprising: a turbocharger including a turbine shaft-coupled to a compressor, the turbine being housed in a turbine housing and the compressor being housed in a compressor housing; a plurality of thermoelectric generators coupled to the turbocharger, at least a subset of the plurality of thermoelectric generators being coupled between the turbine housing and the compressor housing; and an electric supercharger electrically coupled to the plurality of thermoelectric generators. In a first example of the system, the plurality of thermoelectric generators are directly coupled to the turbine housing. In a second example of the system, it optionally includes the first example, wherein each of the plurality of thermoelectric generators includes a hot side and a cold side, each hot side being directly coupled to the turbine housing. In a third example of the system, it optionally includes one or both of the first and second examples, wherein the at least a subset of the plurality of thermoelectric generators is coupled to the compressor housing via a respective cold side. In a fourth example of the system, it optionally includes one or more or each of the first to third examples, the system further comprising a heat shield surrounding the turbine housing, and the plurality of thermoelectric generators being coupled to the heat shield. In a fifth example of the system, it may optionally include one or more, or each of the first to fourth examples, with a first subset of the plurality of thermoelectric generators coupled between the turbine housing and the compressor housing, and a second subset of the plurality of thermoelectric generators coupled to the turbine housing in one or more regions extending around the exhaust inlet and / or exhaust outlet of the turbine. In a sixth example of the system, it may optionally include one or more, or each of the first to fifth examples, and the system further includes a current sensor configured to measure the amount of current generated by the plurality of thermoelectric generators. In a seventh example of the system, it may optionally include one or more, or each of the first to sixth examples, with the turbocharger coupled to the engine, and the system further includes a controller that stores instructions in a non-transitory memory, the instructions being executable by the controller to adjust one or more engine operating parameters based on the amount of current generated by the plurality of thermoelectric generators.

[0083] Another example provides a method comprising: generating current from one or more thermoelectric generators coupled to a turbocharger fluidly coupled to an engine; selectively directing the current to an electric motor to drive an electric compressor in an intake passage coupled upstream of the compressor of the turbocharger; and adjusting one or more engine operating parameters based on the amount of current generated by the one or more thermoelectric generators, measured relative to an estimated amount of current. In a first example of the method, the estimated amount of current is based on an estimated temperature difference across the one or more thermoelectric generators, the estimated temperature difference being based on one or more of the following: a previously measured amount of current generated by the one or more thermoelectric generators, intake mass flow rate, exhaust mass flow rate, intake temperature, exhaust temperature, turbine speed, electric compressor load, boost pressure, and hood temperature. In a second example of the method, which optionally includes the first example, adjusting the one or more engine operating parameters based on the measured amount of current relative to the estimated amount includes: limiting engine torque in response to the measured amount of current being less than the estimated amount of current when the electric compressor is commanded to operate at a threshold load.

[0084] It should be noted that the exemplary control and estimation routines included herein can be used with various engine and / or vehicle system configurations. The control methods and routines disclosed herein can be stored as executable instructions in non-transitory memory and can be executed by a control system including a controller in conjunction with various sensors, actuators, and other engine hardware. The specific routines described herein can represent one or more of any number of processing strategies such as event-driven, interrupt-driven, multitasking, multithreading, etc. Thus, the various actions, operations, and / or functions shown can be executed in the order shown, can be executed in parallel, or may be omitted in some cases. Similarly, the processing order is not necessarily necessary to achieve the features and advantages of the exemplary embodiments described herein, but is provided for ease of illustration and description. One or more of the actions, operations, and / or functions shown can be repeatedly executed according to the specific strategy used. Furthermore, the actions, operations, and / or functions can be graphically represented as code to be programmed into the non-transitory memory of a computer-readable storage medium in an engine control system, wherein the actions are implemented by executing the instructions in conjunction with an electronic controller in a system including various engine hardware components.

[0085] It should be understood that the configurations and routines disclosed herein are exemplary in nature, and these specific embodiments should not be considered limiting, as many variations are possible. For example, the above techniques can be applied to V-6, I-4, I-6, V-12, opposed 4-cylinder, and other engine types. The subject matter of this disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and configurations disclosed herein, as well as other features, functions, and / or properties.

[0086] The following claims specifically point to certain combinations and sub-combinations that are considered novel and not obvious. These claims may refer to a “one” element or a “first” element or its equivalent. Such claims should be understood to include a combination of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and sub-combinations of the disclosed features, functions, elements, and / or properties may be claimed by amending the claims herein or by presenting new claims in this application or related applications. Such claims, whether broader, narrower, identical, or different from the scope of the original claims, are considered to be included within the subject matter of this disclosure.

[0087] According to the present invention, a method includes adjusting one or more engine operating parameters based on the amount of current generated from one or more thermoelectric generators coupled to a turbocharger.

[0088] According to one embodiment, adjusting one or more engine operating parameters based on the amount of current generated from one or more thermoelectric generators includes: adjusting the engine torque limit based on the amount of current generated from one or more thermoelectric generators.

[0089] According to one embodiment, adjusting the engine torque limit based on the amount of current generated from one or more thermoelectric generators includes: indicating a degradation of the exhaust valve coupled to the turbocharger across the turbocharger based on the amount of current generated from the one or more thermoelectric generators, and adjusting the engine torque limit in response to the indication.

[0090] According to one embodiment, indicating the deterioration of a turbine-coupled exhaust valve across the turbocharger based on the amount of current generated from the one or more thermoelectric generators includes: measuring a first amount of current generated from the one or more thermoelectric generators when the exhaust valve is commanded to a first position; measuring a second amount of current generated from the one or more thermoelectric generators when the exhaust valve is commanded to a second position; and indicating the deterioration of the exhaust valve in response to the first amount of current being within a threshold range of the second amount of current.

[0091] According to one embodiment, adjusting the engine torque limit based on the amount of current generated from one or more thermoelectric generators includes: indicating a degradation of an electric supercharger coupled upstream of a compressor of the turbocharger based on the amount of current generated from the one or more thermoelectric generators, and adjusting the engine torque limit in response to the indication.

[0092] According to one embodiment, indicating the degradation of the electric supercharger based on the amount of current generated from the one or more thermoelectric generators includes: measuring a first amount of current generated from the one or more thermoelectric generators when the electric supercharger is deactivated; measuring a second amount of current generated from the one or more thermoelectric generators when the electric supercharger is commanded to operate under a given load; and indicating the degradation of the electric supercharger in response to the first amount of current being within a threshold range of the second amount of current.

[0093] According to one embodiment, adjusting one or more engine operating parameters based on the amount of current generated from one or more thermoelectric generators includes: adjusting the position of the exhaust valve of the turbine coupled across the turbocharger based on the amount of current generated by the one or more thermoelectric generators.

[0094] According to one embodiment, adjusting the position of the turbine-coupled exhaust valve across the turbocharger based on the amount of current generated by the one or more thermoelectric generators includes: opening the exhaust valve in response to the amount of current generated by the one or more thermoelectric generators exceeding a threshold amount.

[0095] According to one embodiment, current generated by the one or more thermoelectric generators flows to the battery.

[0096] According to the present invention, a system is provided comprising: a turbocharger including a turbine coupled to a compressor via a shaft, the turbine being housed in a turbine housing and the compressor being housed in a compressor housing; a plurality of thermoelectric generators coupled to the turbocharger, at least a subset of the plurality of thermoelectric generators being coupled between the turbine housing and the compressor housing; and an electric supercharger electrically coupled to the plurality of thermoelectric generators.

[0097] According to one embodiment, the plurality of thermoelectric generators are directly coupled to the turbine housing.

[0098] According to one embodiment, each of the plurality of thermoelectric generators includes a hot side and a cold side, with each hot side directly coupled to the turbine housing.

[0099] According to one embodiment, at least one subset of the plurality of thermoelectric generators is coupled to the compressor housing via a respective cold side.

[0100] According to one embodiment, a further feature of the invention is a heat shield surrounding the turbine housing, wherein the plurality of thermoelectric generators are coupled to the heat shield.

[0101] According to one embodiment, a first subset of the plurality of thermoelectric generators is coupled between the turbine housing and the compressor housing, and a second subset of the plurality of thermoelectric generators is coupled to the turbine housing in one or more regions extending around the exhaust inlet and / or exhaust outlet of the turbine.

[0102] According to one embodiment, a further feature of the invention is a current sensor configured to measure the amount of current generated by the plurality of thermoelectric generators.

[0103] According to one embodiment, the turbocharger is coupled to the engine, and the system further includes a controller that stores instructions in a non-transitory memory, the instructions being executable by the controller to adjust one or more engine operating parameters based on the amount of current generated by the plurality of thermoelectric generators.

[0104] According to the present invention, a method includes: generating current from one or more thermoelectric generators coupled to a turbocharger of a vehicle, the turbocharger being fluidly coupled to an engine; selectively directing the current to an electric motor to drive an electric compressor in an intake passage coupled upstream of a compressor of the turbocharger; and adjusting one or more engine operating parameters based on the amount of current generated by the one or more thermoelectric generators, measured relative to an estimated amount of current.

[0105] According to one embodiment, the estimated current is based on an estimated temperature difference across the one or more thermoelectric generators, the estimated temperature difference being based on one or more of the following: previously measured current generated by the one or more thermoelectric generators, intake mass flow rate, exhaust mass flow rate, intake temperature, exhaust temperature, turbine speed, electric compressor load, boost pressure, and hood temperature.

[0106] According to one embodiment, adjusting the one or more engine operating parameters based on the measured current quantity relative to the estimated quantity includes: limiting engine torque in response to the measured current quantity being less than the estimated current quantity by a threshold amount when the electric compressor is commanded to operate under a threshold load.

Claims

1. A method for a vehicle, comprising: Adjusting engine torque limits based on the amount of current generated from one or more thermoelectric generators coupled to the turbocharger includes: indicating a degradation of the exhaust valve coupled across the turbocharger via the amount of current generated from the one or more thermoelectric generators, and adjusting the engine torque limits in response to the indication.

2. The method of claim 1, wherein indicative of the degradation of the turbine-coupled exhaust valve across the turbocharger based on the amount of current generated from the one or more thermoelectric generators comprises: When the exhaust valve is commanded to the first position, a first current quantity generated from the one or more thermoelectric generators is measured. When the exhaust valve is commanded to the second position, the amount of a second current generated from the one or more thermoelectric generators is measured. as well as The deterioration of the exhaust valve is indicated in response to the first current quantity being within the threshold range of the second current quantity.

3. The method of claim 1, wherein adjusting the engine torque limit based on the amount of current generated from one or more thermoelectric generators comprises: The degradation of the electric supercharger coupled upstream of the compressor of the turbocharger is indicated based on the amount of current generated from the one or more thermoelectric generators, and the engine torque limit is adjusted in response to the indication.

4. The method of claim 3, wherein indicative of the degradation of the electric supercharger based on the amount of current generated from the one or more thermoelectric generators comprises: When the electric booster is deactivated, the first current generated from the one or more thermoelectric generators is measured. When the electric supercharger is commanded to operate under a given load, the amount of a second current generated from the one or more thermoelectric generators is measured; as well as The degradation of the electric supercharger is indicated in response to the first current quantity being within the threshold range of the second current quantity.

5. The method of claim 1, comprising: The position of the exhaust valve, which is turbine-coupled across the turbocharger, is adjusted based on the amount of current generated by the one or more thermoelectric generators.

6. The method of claim 5, wherein adjusting the position of the turbine-coupled exhaust valve across the turbocharger based on the amount of current generated by the one or more thermoelectric generators comprises: The exhaust valve is opened in response to the current generated by the one or more thermoelectric generators exceeding a threshold amount.

7. The method of claim 1, further comprising: The current generated by the one or more thermoelectric generators flows to the battery.

8. A system for a vehicle, comprising: A turbocharger including a turbine coupled to a compressor via a shaft, the turbine being housed in a turbine housing and the compressor being housed in a compressor housing; A plurality of thermoelectric generators, the plurality of thermoelectric generators being coupled to the turbocharger, at least a subset of the plurality of thermoelectric generators being coupled between the turbine housing and the compressor housing; An electric booster, which is electrically coupled to the plurality of thermoelectric generators; as well as A controller that stores instructions in a non-transitory memory, the instructions being executable by the controller to adjust engine torque limits based on the amount of current generated from a plurality of thermoelectric generators, including: indicating deterioration of the exhaust valve coupled across the turbocharger based on the amount of current generated from the plurality of thermoelectric generators, and adjusting the engine torque limits in response to the indication.

9. The system of claim 8, wherein the plurality of thermoelectric generators are directly coupled to the turbine housing, and wherein each of the plurality of thermoelectric generators includes a hot side and a cold side, each hot side being directly coupled to the turbine housing.

10. The system of claim 9, wherein at least one subset of the plurality of thermoelectric generators is coupled to the compressor housing via a respective cold side.

11. The system of claim 8, further comprising a heat shield surrounding the turbine housing, wherein the plurality of thermoelectric generators are coupled to the heat shield.

12. The system of claim 8, wherein a first subset of the plurality of thermoelectric generators is coupled between the turbine housing and the compressor housing, and wherein a second subset of the plurality of thermoelectric generators is coupled to the turbine housing in one or more regions extending around the exhaust inlet and / or exhaust outlet of the turbine.

13. The system of claim 8, wherein the turbocharger is coupled to the engine, and wherein the system further comprises: A current sensor configured to measure the amount of current generated by the plurality of thermoelectric generators.

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