Method for determining target actuator values ​​of an engine using Model Predictive Control in order to meet target specifications with regard to emissions and driving characteristics and to maximize fuel efficiency

Abstract

Procedure, comprehensive: Generating a setpoint for an actuator of a motor (102); Generating a setpoint for another actuator of the motor (102); Generating a set of possible corrections for each target value; Predictions of an operating parameter for each set of possible corrections, wherein the predicted operating parameter includes an emission value and / or an operating parameter of an exhaust system (132); Determining the cost of each set of possible corrections; Selecting one set of possible corrections from the multiple sets of possible corrections based on cost; Determine whether the predicted operating parameter satisfies a constraint for the selected set; Adjusting the setpoints using the possible corrections of the selected set if the predicted operating parameter satisfies the constraint; and Control of the motor actuator (102) based on the adjusted setpoint.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to internal combustion engines and, more particularly, to a method for determining desired actuator values ​​of an engine using model predictive control to meet target emissions and drivability specifications and to maximize fuel efficiency. EP 2 192 294 B1 describes a method for operating an internal combustion engine, within the framework of which a correction of individual actuators is carried out with regard to various emissions. The starting point for the described method is a cost function J which, on the one hand, takes into account six target or reference values ​​for the emissions and, on the other hand, the target or reference value for the torque. The cost function J contains the corresponding variable emission values ​​as variable variables, which are modified sequentially and in groups such that the value J of the cost function is minimized. In this way, actual values ​​for the various emission types for which the cost function is minimal can be determined. Once the desired emissions that minimize the cost function have been determined in this way, the respective actuator target variables are then determined on the basis of corresponding lookup tables.

[0002] Furthermore, DE 10 2009 021 387 A1 describes a method for applying an engine control system to an internal combustion engine of a motor vehicle. To enable improved application, the method comprises the following steps: - Determining a characteristic map of the engine control system which, during steady-state operation of the internal combustion engine, assigns a control variable to an actual state variable of the internal combustion engine for controlling the internal combustion engine, - Determining a value of the actual state variable for a transient operating mode of the internal combustion engine using a transient engine model of the internal combustion engine, - Determining a support point of the characteristic map which assigns the control variable to the value of the actual state variable occurring during the transient operation of the combustion engine, - Determining a transient control variable for the support point by means of a trade-off model, wherein the transient control variable can be optimized by means of the trade-off model with regard to at least two exhaust gas-relevant output variables of the internal combustion engine, and - Supplementing the support point of the characteristic map with the transient control variable, whereby for the transient operating mode by means of the characteristic map of the engine control the combustion engine can be controlled for the actual state variable by means of the transient control variable and for the stationary operating mode by means of the control variable.

[0003] Further prior art is also evident from DE 10 2015 202 135 A1, which, however, was not yet known on the priority date relevant here. BACKGROUND

[0004] Internal combustion engines burn a fuel / air mixture in cylinders to move the pistons and produce drive torque. The air supply to the engine is controlled by a throttle. More specifically, the throttle controls the throttle range, which increases or decreases the air supply to the engine. As the throttle range increases, the air supply to the engine also increases. A fuel control system adjusts the amount of fuel injected to supply the cylinders with a desired fuel / air mixture and / or achieve a desired torque output. An increased supply of fuel and air to the cylinders increases the engine's torque output.

[0005] In spark-ignition engines, an ignition spark triggers the combustion of a fuel / air mixture delivered to the cylinders. In compression-ignition engines, the fuel / air mixture delivered to the cylinders is ignited by compression within the cylinders. Ignition timing and air delivery can be the key factors controlling the torque output of spark-ignition engines, while fuel delivery can be the key factor controlling the torque output of compression-ignition engines.

[0006] Engine control systems were developed to regulate engine output torque and achieve a desired torque. However, conventional engine control systems do not regulate engine output torque with the required accuracy. Furthermore, conventional engine control systems do not provide a rapid response to control signals or coordinate engine torque control among multiple devices that affect engine output torque.

[0007] The invention is based on the object of providing a motor control method that operates with the required accuracy and enables a rapid response to changing control signals. SUMMARY

[0008] This problem is solved by a method having the features of claim 1.

[0009] A system may include a target generation module, a Model Predictive Control (MPC) module, and an actuator module. The target generation module generates target values ​​for an actuator of an engine. The MPC module generates a set of possible corrections to the target values ​​and predicts an operating parameter for the set of possible corrections. The predicted operating parameter includes an emissions value and / or an operating parameter of an exhaust system. The MPC module determines the cost for the set of possible corrections and selects a set of possible adjustments from multiple sets of possible adjustments based on the cost. The MPC module determines whether the predicted operating parameter for the selected set meets a constraint and adjusts target values ​​using the possible corrections of the possible sets if the predicted operating parameter meets the constraint. The actuator module controls the actuator based on the adjusted target values.

[0010] Further areas of applicability of the present disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are provided for purposes of illustration only. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The present invention will become more fully understood with the aid of the detailed description and the accompanying drawings, in which: Fig. 1 is a functional block diagram of an exemplary engine system according to the present disclosure; Fig. 2 is a functional block diagram of an exemplary engine control system according to the present disclosure; Fig. 3 is a functional block diagram of an exemplary target generation module according to the present disclosure; Fig. 4 is a functional block diagram of an exemplary prediction module according to the present disclosure; and Fig. 5 is a flowchart illustrating an exemplary method for controlling a throttle valve, a swirl flap, an intake and exhaust valve phaser, a wastegate valve, an exhaust gas recirculation (EGR) valve, an EGR cooler bypass valve, spark timing, and fueling using model predictive control in accordance with the present disclosure.

[0012] In the drawings, the same reference numbers are used for similar and / or identical elements. DETAILED DESCRIPTION

[0013] An engine control module (ECM) controls an engine's torque output. More specifically, the ECM controls the engine's actuators based on desired torque. For example, the ECM controls intake and exhaust camshaft phasing based on the desired intake and exhaust camshaft phaser angle, a throttle valve based on a desired throttle valve opening, an exhaust gas recirculation (EGR) valve based on a desired EGR opening, and a turbocharger wastegate valve based on a desired wastegate duty cycle.

[0014] The ECM could determine the setpoints individually using multiple single-input, single-output (SISO) controllers, such as proportional-integral-derivative (PID) controllers. However, when multiple SISO controllers are used, the setpoints can only ensure system stability at the expense of potential fuel savings. Furthermore, the calibration and design of each SISO controller can be costly and time-consuming.

[0015] The ECM presented in the present disclosure generates the setpoints using a Model Predictive Control (MPC) module. The MPC module determines possible setpoint sets based on an engine torque request. The MPC module predicts parameters for each of the possible sets based on the setpoints of the possible sets and a mathematical model of the engine.

[0016] The MPC module can determine the costs associated with using the possible setpoint sets. The costs determined for a possible set can increase if differences between the setpoints of the possible sets and reference values ​​increase, and vice versa. The MPC module can select the possible set with the lowest costs. Instead of, or in addition to, determining the possible setpoint sets and the costs of each set, the MPC module can generate a curve graph displaying the costs of the possible setpoint sets. The MPC module can then determine the possible set with the lowest costs based on the curve slope.

[0017] The MPC module can determine whether the predicted parameters of the selected set satisfy constraints. If so, the MPC module can set the setpoints based on the selected set. Otherwise, the MPC module can select the possible set with the second lowest cost and check this set for constraint satisfaction. The process of selecting a set and checking the set for constraint satisfaction can be referred to as iteration. Multiple iterations can be performed within each control loop.

[0018] An ECM can generate desired actuator values ​​that affect combustion using MPC in the manner described above, while separately controlling desired actuator values ​​that affect the emission levels and operating parameters of an exhaust system. Some desired actuator values ​​that affect combustion also affect the emission levels and exhaust system parameters. Examples of such desired actuator values ​​include a desired main injection quantity and a desired throttle range. Other desired actuator values, such as a desired post injection quantity, affect only the emission levels and exhaust system parameters. In any case, separately controlling these desired actuator values ​​requires calibration effort to develop relationships between the desired actuator values ​​and the emission levels or exhaust system parameters and does not optimize the desired actuator values.

[0019] The ECM of the present disclosure coordinately controls desired actuator values ​​that affect combustion and desired actuator values ​​that affect emissions and exhaust system parameters. The ECM does this by using the MPC module to predict certain parameters, including emissions and exhaust system parameters, for a selected set of possible corrections to the desired values. The MPC module then determines whether the predicted parameters satisfy the constraints. If so, the MPC module sets the desired values ​​based on the selected set. Otherwise, the MPC module selects the second-lowest-cost possible set and checks this set for constraint satisfaction. The MPC module continues in this manner until the MPC module determines the lowest-cost set of possible desired values ​​that satisfy the constraints.In this way, the ECM uses MPC to optimize target actuator values ​​that affect emissions and exhaust system parameters with less calibration effort.

[0020] With reference now to Fig. 1, a vehicle system 100 includes an engine 102 that combusts a fuel / air mixture to generate drive torque for a vehicle. The amount of drive torque generated by the engine 102 is based on a driver input from a driver input module 104. The engine 102 may be a spark-ignition engine (e.g., a gasoline engine) or a compression-ignition engine (e.g., a diesel engine).

[0021] Air is drawn through an intake manifold 110 via a throttle valve 112. The throttle valve 112 may include a butterfly valve with a rotatable vane. An engine control module (ECM) 114 controls a throttle actuator module 116, which in turn controls the opening of the throttle valve 112 to regulate the amount of air drawn into the intake manifold 110.

[0022] Air from intake manifold 110 is drawn into the cylinders of engine 102. Although engine 102 may include multiple cylinders, only a single representative cylinder 118 is shown here for illustrative purposes. For example only, engine 102 may include 2, 3, 4, 5, 6, 8, 10, and / or 12 cylinders. The ECM 114 may instruct a cylinder actuator module 119 to selectively deactivate some of the cylinders, which may improve fuel efficiency under certain engine operating conditions.

[0023] Air from intake manifold 110 is drawn into each cylinder of engine 102 through a swirl flap 120. Swirl flap 120 may include a butterfly valve with a rotatable vane. Swirl flap 120 may be smaller than an intake passage in intake manifold 110, within which swirl flap 120 is positioned such that air can flow around swirl flap 120 when swirl flap 120 is closed. ECM 114 controls a swirl actuator module 121, which in turn controls the opening of swirl flap 120 to control the amount of swirl in intake manifold 110. Swirl flap 120 may close swirl flap 120 when engine 102 is idling to create swirl in intake manifold 110. As the speed of the engine 102 increases, the swirl actuator module 121 may gradually open the swirl flap 120 until the swirl flap 120 is parallel to the intake airflow.

[0024] The engine 102 is capable of operating in a four-stroke cycle. The four strokes described below may be referred to as the intake stroke, compression stroke, combustion stroke, and exhaust stroke. During each revolution of a crankshaft (not shown), two of the four strokes occur within cylinder 118. Accordingly, two revolutions of the crankshaft are required for cylinder 118 to complete all four strokes.

[0025] During the intake stroke, air is drawn from intake manifold 110 through intake valve 122 into cylinder 118. ECM 114 controls a fuel actuator module 124, which regulates the fuel injection performed by injector 125a to achieve a desired air / fuel ratio. Injector 125a may perform pilot injection, main injection, and post injection. Injector 125a may inject fuel into intake manifold 110 at a central location or at multiple locations, such as near intake valve 122 of each of the cylinders. In various implementations, injector 125a may inject fuel directly into the cylinders or into mixing chambers communicating with the cylinders. The fuel actuator module 124 may stop injecting fuel into the deactivated cylinders.The fuel actuator module 124 also regulates fuel injections from the injector 125b. The injector 125b injects fuel into an exhaust gas produced by the engine 102. The fuel injection performed by the injector 125b may be referred to as exhaust injection.

[0026] The injected fuel mixes with air to form a fuel / air mixture within cylinder 118. During the compression stroke, a piston (not shown) within cylinder 118 compresses the fuel / air mixture. Based on a signal from the ECM 114, an ignition actuator module 126 applies voltage to a spark plug 128 within cylinder 118, which ignites the fuel / air mixture. The timing of the spark may be set so that the piston is at its topmost position, known as top dead center (TDC).

[0027] The ignition actuator module 126 may be controlled by a timing signal that determines how long before or after TDC the spark should be initiated. Because piston position is directly related to crankshaft rotation, the function of the spark actuator module 126 may be synchronized with the crankshaft angle. Generating the spark may be referred to as ignition. The spark actuator module 126 may have the ability to change the ignition timing for each ignition event. The ignition actuator module 126 may delay the ignition timing for a next ignition if the ignition timing was changed between a last ignition and the next ignition. The ignition actuator module 126 may disable ignition for deactivated cylinders.

[0028] During the combustion stroke, the combustion of the fuel / air mixture propels the piston from TDC, thereby driving the crankshaft. The combustion stroke can be defined as the time between the moment the piston reaches TDC and the moment the piston reaches bottom dead center (BDC). During the exhaust stroke, the piston moves away from BDC and expels the combustion waste products through an exhaust valve 130. The combustion waste products are expelled from the vehicle via an exhaust system 132.

[0029] The exhaust system 132 may include a three-way catalyst (TWC) 134, an SCR (selective catalytic reduction) catalyst 136, and a particulate filter (PF) 138. When the air-fuel ratio of the engine 102 becomes rich or stoichiometric, the TWC 134 reduces hydrocarbons, carbon monoxide, and nitrogen oxide and produces ammonia, with the SCR catalyst 136 storing the ammonia. When the air-fuel ratio is lean, the TWC 134 reduces hydrocarbons and carbon monoxide, and the ammonia stored in the SCR catalyst 136 is used to reduce nitrogen oxide.

[0030] The exhaust system 132, as described above, may be used when the engine 102 is a spark-ignition engine. If the engine 102 is a compression-ignition engine, the TWC 134 may be omitted from the exhaust system 132. Additionally, a dosing system (not shown) may inject a dosing agent, such as urea, into the exhaust system 132. The dosing agent decomposes to form ammonia, which is stored in the SCR catalyst 136.

[0031] The PF 138 filters particulate matter, such as soot, from the exhaust gas flowing through the exhaust system 132. The ECM 114 may control the injector 125a via the fuel actuator module 124 to perform a post-injection to regenerate the PF 138. Additionally or alternatively, the ECM 114 may control the injector 125b via the fuel actuator module 124 to inject fuel into the exhaust system 132 to regenerate the PF 138.

[0032] The intake valve 122 may be controlled by an intake camshaft 140, while the exhaust valve 130 may be controlled by an exhaust camshaft 142. In various implementations, multiple intake camshafts (including the intake camshaft 140) may control multiple intake valves (including the intake valve 122) for the cylinder 118 and / or may control the intake valves (including the intake valve 122) of multiple cylinder banks (including the cylinder 118). Similarly, multiple exhaust camshafts (including the exhaust camshaft 142) may control multiple exhaust valves for the cylinder 118 and / or may control exhaust valves (including the exhaust valve 130) of multiple cylinder banks (including the cylinder 118). In various implementations, the intake valve 122 and / or the exhaust valve 130 may be controlled by devices other than camshafts, such asby camless valve actuators. The cylinder actuator module 119 can deactivate the cylinder 118 by disabling the opening of the intake valve 122 and / or the exhaust valve 130.

[0033] The time when the intake valve 122 opens may be varied relative to the piston's TDC by an intake cam phaser 148. The time when the exhaust valve 130 opens may be varied relative to the piston's TDC by an exhaust cam phaser 150. A phaser actuator module 158 may control the intake cam phaser 148 and the exhaust cam phaser 150 based on signals from the ECM 114. If implemented, a variable valve train (not shown) may also be controlled by the phaser actuator module 158.

[0034] The engine system 100 may include a turbocharger, which in turn includes a hot gas turbine 160-1 driven by the hot exhaust gases flowing through the exhaust system 132. The turbocharger also includes a cold air compressor 160-2 driven by the turbine 160-1. The compressor 160-2 compresses the air fed into the throttle valve 112. In various implementations, a crankshaft-driven turbocharger (not shown) may compress the air from the throttle valve 112 and deliver the compressed air into the intake manifold 110.

[0035] A wastegate 162 may direct exhaust gases past the turbine 160-1, thereby reducing the boost pressure (the amount of intake air compression) generated by the turbocharger. The boost actuator module 164 may regulate the boost pressure of the turbocharger by controlling the opening of the wastegate 162. In various implementations, two or more turbochargers may be used, which may be controlled by the boost actuator module 164.

[0036] An air cooler (not shown) may transfer heat from the compressed charge air to a cooling medium, such as engine coolant or air. An air cooler that cools the compressed charge air using engine coolant may be referred to as an intercooler. An air cooler that cools the compressed charge air using air may be referred to as a charge air cooler. The compressed charge air may be heated, for example, by compression and / or by other components of the exhaust system 132. Although shown separately for illustrative purposes, the turbine 160-1 and the compressor 160-2 may be connected to each other and direct the intake air near hot exhaust gases.

[0037] The engine system 100 may include a high-pressure (HP) exhaust gas recirculation (EGR) valve 170 and a low-pressure (LP) exhaust gas recirculation (EGR) valve 171 that selectively recirculate exhaust gas to the intake manifold 110. The HP EGR valve 170 may be located upstream of the turbocharger turbine 160-1. The LP EGR valve 171 may be located downstream of the turbocharger turbine 160-1. The EGR valves 170 and 171 may be controlled by an EGR actuator module 172 based on signals from the ECM 114.

[0038] The engine system 100 may also include an EGR cooler 174 and an EGR cooler bypass valve 176. The EGR cooler 174 may be located downstream of the HP EGR valve 170 and may cool the high-pressure exhaust gas flowing through the HP EGR valve 170. The EGR cooler bypass valve 176 may allow high-pressure exhaust gas to bypass the EGR cooler 174 when the EGR cooler bypass valve 176 is open. The EGR cooler bypass valve 176 may be controlled by a bypass actuator module 178 based on signals from the ECM 114. The ECM 114 may open the EGR cooler bypass valve 176 when the engine 102 is initially started to more quickly increase the temperature of the engine 102 and / or components of the exhaust system 132 to their operating temperatures.

[0039] A crankshaft position may be measured using a crankshaft position sensor 180. A crankshaft speed (engine speed) may be determined based on the crankshaft position. An engine coolant temperature may be measured using an engine coolant temperature (ECT) sensor 182. The ECT sensor 182 may be located within the engine 102 or at other locations where the coolant is circulated, such as a radiator (not shown).

[0040] The pressure in the intake manifold 110 may be measured using a manifold absolute pressure (MAP) sensor 184. In various implementations, engine vacuum, consisting of the difference between ambient air pressure and the pressure in the intake manifold 110, may be measured. The mass flow rate of air flowing through the intake manifold 110 may be measured using a mass airflow (MAF) sensor 186. In various implementations, the MAF sensor 186 may be positioned in a housing that also includes the throttle valve 112.

[0041] The throttle actuator module 116 may monitor the position of the throttle valve 112 using one or more throttle position sensors (TPS) 190. The temperature of the ambient air supplied to the engine 102 may be measured using an intake air temperature (IAT) sensor 192. A nitrogen oxide concentration exiting the exhaust system 132 may be measured using a nitrogen oxide (NOx) sensor 194. The ECM 114 may use signals from the sensors to make control decisions for the engine system 100.

[0042] The ECM 114 may communicate with a hybrid control module 196 to coordinate the operation of the engine 102 and an electric motor 198. The electric motor 198 may also function as a generator, producing electrical energy for use in the vehicle's electrical system or for storage in a battery. In various applications, various functions of the ECM 114 and hybrid control module 196 may be integrated into one or more modules.

[0043] Any system that affects an engine parameter can be referred to as an engine actuator. For example, the throttle actuator module 116 can adjust the opening of the throttle valve 112 to achieve a desired throttle valve opening range. The ignition actuator module 126 controls the spark plugs to achieve a desired ignition timing relative to piston top dead center. The fuel actuator module 124 controls the injectors to achieve certain fuel delivery setpoints. The phaser actuator module 158 can control the intake and exhaust cam phasers 148 and 150 to achieve desired phaser angles for the intake and exhaust cams, respectively. The EGR actuator module 172 can control each of the EGR valves 170 and 171 to achieve a desired EGR opening range.The ECM 114 may adjust the desired EGR opening range for each of the EGR valves 170 and 171 to achieve a desired split between the high-pressure exhaust flowing through the HP EGR valve 170 and the low-pressure exhaust flowing through the LP EGR valve 171. The boost actuator module 164 controls the wastegate 162 to achieve a desired opening range for the wastegate. The cylinder actuator module 119 controls cylinder deactivation to achieve a desired number of activated and deactivated cylinders.

[0044] The ECM 114 generates the desired engine actuator values ​​to enable the engine 102 to produce a desired engine output torque. The ECM 114 generates the desired engine actuator values ​​using model predictive control, as discussed in more detail below.

[0045] Referring to Fig. 2, an exemplary implementation of the ECM 114 includes a drive torque module 202. The driver torque module 202 determines a driver torque request 204 based on a driver input 206 from the driver input module 104. The driver input 206 may be based, for example, on an accelerator or brake pedal position. The driver input 206 may also be based on cruise control, which may be an adaptive cruise control system that varies vehicle speed to maintain a predetermined following distance. The driver torque module 202 may store one or more mappings of accelerator pedal positions to desired torques and determine the driver torque request 204 based on a selected mapping. The driver torque module 202 may also apply one or more filters to estimate boundary changes in the driver torque request 204.

[0046] An axle torque arbitration module 208 arbitrates between the driver torque request 204 and other axle torque requests 210. Axle torque (torque at the wheels) may be generated from various sources, including an engine and / or an electric motor. For example, axle torque request 210 may include a torque reduction requested by a traction control system when positive wheel slip is detected. Positive wheel slip occurs when the axle torque overcomes the friction between the wheels and the road surface, and the wheels begin to slip on the road surface. Axle torque requests 210 may also include a torque increase request to counteract negative wheel slip, which occurs when a tire of the vehicle slips in the opposite direction relative to the road surface because the axle torque is negative.

[0047] Axle torque request 210 may also include brake management requests and vehicle overspeed torque requests. Brake management requests may reduce axle torque to ensure that the axle torque does not exceed the brakes' ability to stop the vehicle when the vehicle stops. Vehicle overspeed torque requests may reduce axle torque to prevent the vehicle from exceeding a predetermined speed. Axle torque requests 210 may also be generated by vehicle stability control systems.

[0048] The axle torque arbitration module 208 outputs an axle torque request 212 based on the results of the arbitration between the received axle torque requests 204 and 210. As described below, the axle torque request 212 from the axle torque arbitration module 208 may be selectively adjusted by other modules of the ECM 114 before being applied to control the engine actuators.

[0049] The axle torque arbitration module 208 may output the axle torque request 212 to a propulsion torque arbitration module 214. In various implementations, the axle torque arbitration module 208 may output the axle torque request 212 to a hybrid optimization module 216. The hybrid optimization module 216 may determine how much torque should be produced by the engine 102 and how much torque should be produced by the electric motor 198. The hybrid optimization module 216 then outputs a modified axle torque request 218 to the propulsion torque arbitration module 214.

[0050] The propulsion torque arbitration module 214 converts the axle torque request 212 (or the modified axle torque request 218) from an axle torque range (torque at the wheels) to a propulsion torque range (torque at the crankshaft). The propulsion torque arbitration module 214 arbitrates between the (converted) axle torque request 212 and other propulsion torque requests 220. The propulsion torque arbitration module 214 generates a propulsion torque request 222 as a result of the arbitration.

[0051] For example, propulsion torque requests 220 may include torque reductions to protect against engine overspeed, torque increases to prevent stalling, and torque reductions to adjust gear changes. Propulsion torque requests 220 may also be a result of clutch fuel cutoff, which reduces engine output torque to prevent an increase in engine speed when the driver applies the clutch pedal in a manual transmission vehicle.

[0052] The propulsion torque requests 220 may also include an engine shutdown request initiated upon detection of a critical fault. For example, critical faults may include detection of vehicle theft, a stuck starter motor, electronic throttle control issues, and unexpected torque increases. In various implementations, the engine shutdown request is selected as the override request when an engine shutdown request is present. If the engine shutdown request is present, the propulsion torque arbitration module 214 may output zero as the propulsion torque request 222.

[0053] In various implementations, a motor shutdown request may simply shut down motor 102 separately from the arbitration process. The propulsion torque arbitration module 214 may still receive the motor shutdown request so that, for example, appropriate data can be sent as feedback to other torque requesters. For example, all other torque requesters may be informed that they have been ranked lower in the arbitration.

[0054] A torque reserve module 224 generates a torque reserve 226 to compensate for changes in engine operating conditions that decrease engine output torque and / or to compensate for one or more stresses. For example, the air / fuel ratio of the engine 102 and / or the mass air flow rate may be directly changed, such as through intrusive diagnostic equivalence ratio testing and / or new engine purge. Before initiating these procedures, the torque reserve module 224 may generate or increase the torque reserve 226 to quickly compensate for reductions in engine output torque caused by the stretching of the air / fuel mixture during these procedures.

[0055] The torque reserve module 224 may also generate or increase a torque reserve 226 in anticipation of a future load, such as power steering pump operation or air conditioning (A / C) compressor clutch engagement. The torque reserve module 224 may generate or increase the torque reserve 226 for A / C compressor clutch engagement when the driver initially turns on the air conditioning system. Then, when the A / C compressor clutch is engaged, the torque reserve module 224 may decrease the torque reserve 226 by an amount corresponding to the estimated A / C compressor clutch load.

[0056] A target generation module 228 generates target values ​​for the engine actuators based on the propulsion torque request 222, the torque reserve 226, and one or more engine operating conditions. A target adjustment module 229 adjusts the target values ​​using model predictive control (MPC) and outputs the adjusted target values ​​to the corresponding engine actuators.

[0057] The target generation module 228 may generate the target values ​​using a function or mapping that maps the propulsion torque request 222, the torque reserve 226, and the engine operating conditions to the target values. The engine operating conditions may include engine speed, engine coolant temperature, intake manifold pressure, intake air mass flow rate, and / or intake air temperature.

[0058] The propulsion torque request 222 may be a braking torque. The braking torque may be referred to as the torque at the crankshaft under the current operating conditions. The target generation module 228 may convert the propulsion torque request 222 from a braking torque to a base torque using a map or a function that maps braking torques to base torques, and generate the target values ​​based on the base torque. Base torques may be referred to as the torque measured at the crankshaft during engine operation 102 with a torque meter while the engine 102 is warm and the engine 102 is not under torque loads from accessories such as an alternator or an A / C compressor. In various implementations, the target generation module 228 may convert the propulsion torque request 222 to another appropriate torque type, such asan indicated torque, and generate the setpoints based on the converted torque demand. An indicated torque can be defined as a torque at the crankshaft that is based on the work performed during combustion in the cylinders.

[0059] The target values ​​include a wastegate opening range 230, a throttle opening range 232, a swirl flap opening range 233, a HP EGR opening range 234, a LP EGR opening range 235, an intake cam phaser angle 236, and an exhaust cam phaser angle 238. The target values ​​also include a target spark timing 240, a target number 242 of cylinders to be activated, fueling parameters 244, and a target bypass opening range 246 for the EGR cooler bypass valve 176. The boost actuator module 164 controls the wastegate 162 to achieve the wastegate opening range 230.For example, a first conversion module 248 may convert the wastegate target opening range 230 into a target duty cycle 250 applied to the wastegate 162, and the wastegate actuator module 164 may output a signal to the wastegate 162 based on the target duty cycle 250. In various implementations, the first conversion module 248 may convert the wastegate target opening range 230 into a wastegate target position (not shown) and the wastegate target position into the target duty cycle 250.

[0060] The throttle actuator module 116 controls the throttle valve 112 to achieve the desired throttle opening range 232. For example, a second conversion module 252 may convert the desired throttle opening range 232 into a desired duty cycle 254 applied to the throttle valve 112, and the throttle actuator module 116 may output a signal to the throttle valve 112 based on the desired duty cycle 254. In various implementations, the second conversion module 252 may convert the desired throttle opening range 232 into a desired throttle position (not shown) and the desired throttle valve position into the desired duty cycle 254.

[0061] The swirl actuator module 121 controls the swirl flap 120 to achieve the swirl flap target opening range 233. In various implementations, a third conversion module (not shown) may be included and may convert the swirl flap target opening range 233 into a target duty cycle (not shown) to be performed on the swirl flap 120. Alternatively, the third conversion module may convert the swirl flap target opening range 233 into a swirl flap target position (not shown) and the swirl flap target position into the target duty cycle.

[0062] The EGR actuator module 172 controls the HP EGR valve 170 to achieve the HP EGR target opening range 234. For example, a fourth conversion module 256 may convert the HP EGR target opening range 234 into a target duty cycle 258 applied to the HP EGR valve 170, and the EGR actuator module 172 may output a signal to the HP EGR valve 170 based on the target duty cycle 258. In various implementations, the fourth conversion module 256 may convert the HP EGR target opening range 234 into a target EGR position (not shown) and the target EGR position into the target duty cycle 258.

[0063] The EGR actuator module 172 controls the LP EGR valve 171 to achieve the LP EGR target opening range 235. For example, the fourth conversion module 256 may convert the LP EGR target opening range 235 into a target duty cycle 259 applied to the LP EGR valve 171, and the EGR actuator module 172 may output a signal to the LP EGR valve 171 based on the target duty cycle 259. In various implementations, the fourth conversion module 256 may convert the LP EGR target opening range 235 into a target EGR position (not shown) and the target EGR position into the target duty cycle 259.

[0064] The phaser actuator module 158 controls the intake cam phaser 148 to adjust the intake cam phaser desired angle 236. The phaser actuator module 158 also controls the exhaust cam phaser 150 to achieve the exhaust cam phaser desired angle 238. In various implementations, a fifth conversion module (not shown) may be included and convert the intake and exhaust cam phaser desired angles 236 and 238, respectively, into intake and exhaust desired duty cycles. The phaser actuator module 158 may output the intake and exhaust desired duty cycles to the intake and exhaust cam phasers 148 and 150, respectively.In various implementations, the target generation module 228 may determine a target overlap factor and an effective shift, and the phaser actuator module 158 may control the intake and exhaust cam phasers 148 and 150 to achieve the target overlap factor and the effective shift.

[0065] The wastegate opening range 230, the throttle opening range 232, the swirl valve opening range 233, the HP EGR opening range 234, the LP EGR opening range 235, the intake cam phaser angle 236, and the exhaust cam phaser angle 238 may be referred to as air control setpoints. The throttle opening range 232 may only be used as an air control setpoint when the engine 102 is a spark-ignition engine. Thus, if the engine 102 is a compression-ignition engine, the throttle opening range 232 may not be used as an air control setpoint. Instead, a desired EGR flow rate, a desired boost pressure, and / or a desired engine air flow may be used as air control setpoints.The desired EGR flow rate, the desired boost pressure amount, and / or the desired engine airflow may be achieved by adjusting the wastegate opening area 230, a desired variable geometry turbocharger (VGT) position (if applicable), the desired HP EGR opening area 234, the desired LP EGR opening area 235, the desired intake cam phaser angle 236, and / or the desired exhaust cam phaser angle 238.

[0066] The spark actuator module 126 provides an ignition spark based on the desired ignition timing 240. The cylinder actuator module 119 selectively activates and deactivates the cylinder valves based on the desired number of cylinders 242. Fueling and spark may also be deactivated with cylinders deactivated. The desired fueling parameters 244 may include a desired fuel rail pressure, a desired number of injectors for each combustion event, a desired mass of fuel for each injection, and / or a desired start timing for each injection. The fuel actuator module 124 controls fueling based on the desired fueling parameters 244.In one example, the fuel actuator module 124 may command a pilot injection, a main injection, a post injection, an exhaust injection, and the desired fueling parameters 244 may include a desired mass of fuel and a desired start timing for each pilot, main, post, and exhaust injection.

[0067] The bypass actuator module 178 controls the EGR cooler bypass valve 176 to achieve the desired bypass opening range 246. In various applications, a sixth conversion module (not shown) may be included and may convert the desired bypass opening range 246 into a desired duty cycle (not shown) applied to the EGR cooler bypass valve 176. Alternatively, the sixth conversion module may convert the desired bypass opening range 246 into a desired bypass valve position (not shown) and the desired bypass valve position into the desired duty cycle.

[0068] Fig. 3 is a functional block diagram of an exemplary implementation of the target adjustment module 229. A Model Predictive Control (MPC) module 312 generates the corrections for the target values ​​230-246 using MPC. The MPC module 312 may be a single module or comprise multiple modules. For example, the MPC module 312 may include a sequence determination module 316. The sequence determination module 316 determines possible sequences, also referred to herein as sets, of corrections for the target values ​​230-246 that could be used together during the future N control loops. Each of the possible sequences determined by the sequence determination module 316 includes a sequence of N correction values ​​for each of the target values ​​230-246.In other words, each possible sequence includes a sequence of N correction values ​​for the wastegate opening range 230, a sequence of N correction values ​​for the throttle opening range 232, a sequence of N correction values ​​for the swirl flap opening range 233, a sequence of N correction values ​​for the HP EGR opening range 234, a sequence of N correction values ​​for the LP EGR opening range 235, a sequence of N correction values ​​for the intake cam phaser angle 236, and a sequence of N correction values ​​for the exhaust cam phaser angle 238. Each possible sequence also includes a sequence of N correction values ​​for the target ignition timing 240, the target number of cylinders 242, the target fueling parameters 244, and the target bypass opening range 246. Each of the N correction values ​​corresponds to one of the future N Control loops. N is an integer greater than or equal to one.

[0069] A prediction module 323 predicts responses of the motor 102 to the possible sequences of corrections to the setpoints 230-246 based on a mathematical model 324 of the motor 102, exogenous inputs 328, and feedback inputs 330.For example, based on a possible sequence of corrections for the setpoints 266-270, the exogenous inputs 328, and the feedback inputs 330 using the model 324, the prediction module 323 may generate a sequence of predicted torque of the engine 102 for the N control loops, a sequence of predicted MAPs for the N control loops, a sequence of predicted APCs for the N control loops, a sequence of predicted amounts of external dilution for the N control loops, a sequence of predicted amounts of internal dilution for the N control loops, a sequence of predicted combustion phaser values ​​for the N control loops, a sequence of predicted combustion quality values ​​for the N control loops, and a sequence of predicted effective displacement setpoints for the N control loops.

[0070] The Model 324 may include a function or mapping calibrated based on characteristics of the engine 102. Dilution may be referred to as an amount of exhaust gas from a previous combustion that remains in a cylinder during combustion. External dilution may refer to exhaust gas provided for combustion via the EGR valves 170 and 171. Internal dilution (also referred to as residual dilution) may refer to exhaust gas remaining in a cylinder and / or exhaust gas forced back into the cylinder after the exhaust stroke of a combustion cycle. Effective displacement may be referred to as the volume of air drawn into the cylinders of an engine as pistons move within the cylinders from TDC to BDC, minus any losses in air volume due to pistons forcing air back into the intake manifold through intake valves.

[0071] Combustion phasing may refer to a crankshaft position at which a predetermined amount of injected fuel combusts in a cylinder relative to a predetermined crankshaft position for combustion of the predetermined amount of injected fuel. For example, combustion phasing may be expressed as CA50 relative to a predetermined CA50. CA50 may refer to a crankshaft angle (CA) at which 50 percent of a mass of injected fuel has been combusted in a cylinder. The predetermined CA50 may correspond to a CA50 at which a maximum amount of work is performed on the injected fuel and, in various implementations, may be approximately 8.5 - approximately 10 degrees after TDC (top dead center).While combustion phasing is discussed using CA50 values, another suitable parameter that is representative of combustion phasing can be used. Furthermore, another suitable parameter that is representative of combustion quality can be applied, while combustion quality is discussed as the coefficient of variation (COV) of the indicated mean effective pressure (IMEP).

[0072] The exogenous inputs 328 may include parameters that are not directly influenced by the engine actuators. For example, the exogenous inputs 328 may include engine speed, turbocharger inlet air pressure, IAT, and / or one or more other parameters. The feedback inputs 330 may include, for example, an estimated output torque of the engine 102, an exhaust pressure downstream of the turbocharger turbine 160-1, the IAT, an APC of the engine 102, an estimated internal dilution, an estimated external dilution, MAF, an air-fuel ratio of the engine 102, and / or one or more other suitable parameters. The feedback inputs 330 may be measured using sensors (e.g., the IAT sensor 192) and / or estimated based on one or more other parameters.

[0073] The prediction module 323 also predicts, for each of the possible sequences of corrections for the target values ​​230-246, emission values ​​in the exhaust gas produced by the engine 102, operating parameters of the exhaust system 132, a combustion noise level associated with the engine 102, and / or drivability parameters. The predicted emission values ​​may include a nitrogen oxide (NOx) value in the exhaust gas produced by the engine 102, which may be referred to as engine exhaust NOx. Alternatively or additionally, the predicted emission values ​​may include a soot value in the exhaust gas produced by the engine 102, which may be referred to as engine exhaust soot.

[0074] The predicted operating parameters of the exhaust system 132 may include an amount of soot deposition in the PF 138, an ammonia level stored in the SCR catalyst 136, a temperature of the SCR catalyst 136, and / or a temperature of the PF 138. The amount of soot deposition in the PF 138 may be referred to as PF soot load. The predicted drivability parameters may include vehicle speed and / or vehicle jerk. Vehicle jerk is a second derivative of vehicle speed with respect to time.

[0075] The prediction module 323 may predict the emission levels, the exhaust system operating parameters, the combustion noise level, and the drivability parameters based on, for example, the exogenous inputs 328 and the feedback inputs 330. The prediction module 323 may make these predictions using linear or physics-based models.For example, based on a possible sequence of the setpoints 266-270, the exogenous inputs 328, and the feedback inputs 330 using the physics-based model, the prediction module 323 may generate a sequence of predicted engine outlet NOx values ​​for the N control loops, a sequence of predicted engine outlet soot values ​​for the N control loops, a sequence of predicted PF soot loading for the N control loops, a sequence of predicted ammonia storage values ​​for the N control loops, a sequence of predicted SCR temperatures for the N control loops, a sequence of predicted PF temperatures for the N control loops, a sequence of predicted combustion noise levels for the N control loops, a sequence of predicted vehicle speeds for the N control loops, and a sequence of predicted vehicle jerks for the N control loops.

[0076] The physics-based models used by the prediction module 323 to predict the emission levels, the exhaust system operating parameters, the combustion noise level, and the drivability parameters may be in the form of the following relationship: ƒ(x)=K(∑i=1Nwi(xi−xequilibrium), where f(x) is a function for a predicted parameter, K is an activation function, w i is a weighting value, x i is a model input for the i-th of the N control loops and x equilibrium is a value of the model input that represents a point at which the model is linearized. The weight value wi and the activation function K can depend on the engine speed and engine load, and a fuel quantity can be used as an estimate of an engine load. Therefore, there can be a different function f(x) for each operating point determined by the engine speed and fuel quantity.

[0077] A cost module 332 determines a cost value for each of the possible sequences of corrections to the target values ​​230-246 based on the predicted parameters determined for a possible sequence and may determine the cost value based on reference values ​​340. The cost module 332 may determine the cost value for each of the possible sequences based on relationships between the predicted parameters and the corresponding reference values ​​340. The relationships may be weighted, for example, to control the impact of each relationship on costs.

[0078] A selection module 344 selects one of the possible sequences of corrections for the setpoints 230-246 based on the respective costs of the possible sequences. For example, the selection module 344 may select the possible sequence with the lowest cost that simultaneously satisfies the actuator constraints 348 and the output constraints 352.

[0079] In various implementations, satisfaction of actuator constraints 348 and output constraints 352 may be considered in determining costs. For example, cost module 332 may determine the cost value for each of the possible sequences based on relationships between the predicted parameters and corresponding ones of actuator constraints 348 and output constraints 352.

[0080] The selection module 344 can adjust the target values ​​230-246 based on the first of the N correction values ​​of the selected possible sequence. In other words, the selection module 344 can adjust the wastegate target opening range 230 using the first of the selected sequences of N correction values ​​for the wastegate target opening range 230, adjust the throttle target opening range 232 using the first of the selected sequences of N correction values ​​for the throttle target opening range 232, adjust the swirl flap target opening range 233 using the first of the selected sequences of N correction values ​​for the swirl flap target opening range 233, adjust the HP-EGR target opening range 234 using the first of the selected sequences of N correction values ​​for the HP-EGR target opening range 234,adjust the LP-EGR desired opening range 235 using the first of the selected sequences of N correction values ​​for the LP-EGR desired opening range 235, adjust the intake cam phaser desired angle 236 using the first of the selected sequences of N correction values ​​for the intake cam phaser desired angle 236, and adjust the exhaust cam phaser desired angle 238 using the first of the selected sequences of N correction values ​​for the exhaust cam phaser desired angle 238. The selection module 344 also adjusts the desired spark timing 240 using the first selected sequence of N correction values ​​for the desired spark timing 240, adjusts the desired number of cylinders 242 using the first selected sequence of N correction values ​​for the desired number of cylinders 242,adjusts the desired fueling parameters 244 using the first selected sequence of N correction values ​​for the desired fueling parameters 244 and adjusts the desired bypass range 246 using the first selected sequence of N correction values ​​for the desired bypass range 246.

[0081] In a next control loop, the MPC module 312 identifies possible sequences of corrections, generates the predicted parameters for the possible sequences, determines the costs for each of the possible sequences, selects one of the possible sequences, and adjusts the setpoints 230-246 using the first of the correction values ​​for the setpoints 230-246 in the selected possible sequence. This process continues for each control loop.

[0082] An actuator restriction module 360 ​​(see Fig. 2) sets the actuator constraints 348 for each setpoint 230-246. In other words, the actuator constraints module 360 ​​sets actuator constraints for the throttle valve 112, actuator constraints for the EGR valves 170 and 171, actuator constraints for the wastegate valve 162, actuator constraints for the intake cam phaser 148, and actuator constraints for the exhaust cam phaser 150. The actuator constraints module 360 ​​also sets actuator constraints for the spark actuator module 126, actuator constraints for the cylinder actuator module 119, and actuator constraints for the fuel actuator module 124.

[0083] The actuator constraints 348 for each setpoint 230-246 may include a maximum value for an associated setpoint and a minimum value for that setpoint. The actuator constraint module 360 ​​may generally set the actuator constraints 348 to a predetermined operating range for the associated engine actuators. In particular, the actuator constraint module 360 ​​may generally set the actuator constraints 348 to predetermined operating ranges for each of the throttle valve 112, the EGR valves 170 and 171, the wastegate valve 162, the intake cam phaser 148 and the exhaust cam phaser 150, the ignition actuator module 126, the cylinder actuator module 119, and the fuel actuator module 124. Thus, the maximum value for a setpoint may be a maximum limit of a corresponding actuator, and the minimum value for the setpoint may be a minimum limit of the actuator.

[0084] An output restriction module 364 (see Fig. 2) sets the output constraints 352 for the predicted torque output of the engine 102, the predicted MAP, the predicted APC, the predicted CA50, the predicted COV of the IMEP, the predicted internal dilution, the predicted external dilution, and / or the predicted effective displacement. The output constraints 352 for each predicted parameter may include a maximum value for an associated predicted parameter and a minimum value for that predicted parameter.For example, the output constraints 352 may include a minimum torque, a maximum torque, a minimum MAP, a maximum MAP, a minimum APC, a maximum APC, a minimum CA50, a maximum CA50, a minimum IMEP-COV, a maximum IMEP-COV, a minimum internal dilution, a maximum internal dilution, and a minimum external dilution, a maximum external dilution, a minimum effective displacement, and / or a maximum effective displacement.

[0085] The output constraint module 364 may generally set the respective output constraints 352 to predetermined ranges for the associated predicted parameters. However, the output constraint module 364 may vary one or more output constraints 352 under certain conditions. For example, the output constraint module 364 may delay the maximum CA50 when knocking phenomena occur in the engine 102. In another example, the output constraint module 364 may increase the maximum IMEP-COV under low load conditions, such as engine idle, when a higher IMEP-COV may be required to achieve a given torque request.

[0086] A reference value module 368 (see Fig. 2) generates the reference values ​​340 for the setpoints 230-246. The reference values ​​340 include a reference for each of the setpoints 230-246. In other words, the reference values ​​340 include a reference for the wastegate opening range, a reference for the throttle opening range, a reference for the EGR opening range, a reference for the intake cam phaser angle, and a reference for the exhaust cam phaser angle. The reference values ​​340 also include spark timing, a reference number of cylinders, and fueling reference parameters. The reference values ​​340 may also include a reference for each of the output constraints 352.For example, the reference values ​​340 may include a Manifold Absolute Pressure (MAP) reference, an Air Per Cylinder (APC) reference, an external dilution reference, an internal dilution reference, and an effective displacement reference.

[0087] The reference value module 368 may determine the reference values ​​340 based on the propulsion torque request 222 and / or the base torque request 308. The reference values ​​340 provide references for setting the respective target values ​​266-270. The reference values ​​340 may be used to determine the cost values ​​for possible sequences, as discussed further below. The reference values ​​340 may also be used for one or more other reasons, such as by the sequence determination module 316 to determine possible sequences.

[0088] Instead of, or in addition to, generating sequences of possible setpoint corrections and determining the cost of each of these sequences, the MPC module 312 may identify a sequence of possible setpoint corrections with the lowest cost using convex optimization techniques. For example, the MPC module 312 may determine the corrections for setpoints 230-246 using a quadratic program (QP) solver, such as the Dantzig QP solver. In another example, the MPC module 312 may generate a graph of the cost values ​​for the possible sequences of corrections for setpoints 230-246 and, based on the curve slope, identify a sequence of possible setpoint corrections with the lowest cost.The MPC module 312 may then examine the sequence of possible setpoint corrections to determine whether the sequence of possible setpoint corrections satisfies the actuator constraints 348 and the output constraints 352. If so, the MPC module 312 may adjust the setpoints 230-246 using the first of the N correction values ​​of this selected possible sequence, as described above.

[0089] If the actuator constraints 348 or the output constraints 352 are not satisfied, the MPC module 312 selects another sequence of possible setpoint corrections with the second lowest cost and checks this sequence of possible setpoint corrections for satisfaction of the actuator constraints 348 and the output constraints 352. The process of selecting a sequence and checking the sequence for satisfaction of the actuator constraints 348 and the output constraints 352 may be referred to as an iteration. Multiple iterations may be performed within each control loop.

[0090] The MPC module 312 performs iterations until a sequence with the lowest cost that satisfies the actuator constraints 348 and the output constraints 352 is identified. In this way, the MPC module 312 selects the sequence of possible corrections to setpoints with the lowest cost values ​​that satisfy the actuator constraints 348 and the output constraints 352. If a sequence cannot be identified, the MPC module 312 may indicate that no solution is available.

[0091] The cost module 332 may determine the costs for the possible sequences of corrections to the setpoints 230-246 based on a total amount of fuel injected into the cylinders of the engine 102 and the exhaust system 132, as well as the combustion noise level of the engine 102. For example, the cost module 332 may determine the costs for a possible sequence of corrections to the setpoints 230-246 based on the following equation: Cost=∑i=1N[PFi+wCN∗PCNi], depending on the actuator constraints 348 and the output constraints 352. Cost is the cost for the possible sequence of corrections for the setpoints 230-246, PFi is a possible total fuel delivery for the i-th of the N control loops, PCNi is the predicted combustion noise level for the i-th of the N control loops, and wCN is a weighting value associated with the predicted combustion noise level. The possible total fuel delivery PFi may include a total amount of fuel injected during a pilot injection, a main injection, a post injection, and an exhaust injection for the i-th of the N control loops. In various applications, the predicted combustion noise level and the associated weighting value may be omitted from the above equation, and the predicted combustion noise level may instead be subject to a corresponding output constraint 352.

[0092] When the cost module 332 uses the above equation to determine costs, selecting the lowest-cost possible sequence of corrections for the target values ​​230-246 may be subject to output constraints 352 relating to emissions levels, exhaust system parameters, and drivability parameters. For example, the output constraints 352 may include a maximum engine exhaust NOx level, a maximum engine soot level, a maximum PF soot load, a maximum ammonia storage level, a maximum SCR temperature, a maximum PF temperature, a maximum combustion noise level, a minimum vehicle speed, a maximum vehicle speed, a minimum vehicle jerk, and a maximum vehicle jerk.The possible sequence of corrections for the setpoints 230-246 can satisfy the output constraints 352 if the corresponding predicted parameters are smaller than the maximum output constraints and larger than the minimum output constraints 352.More specifically, the possible sequence of corrections for the setpoints 230-246 may satisfy the output constraints 352 if the predicted engine outlet NOx value is less than the maximum engine outlet NOx value, the predicted engine outlet soot value is less than the maximum engine outlet soot value, the predicted PF soot load is less than the maximum PF soot load, the predicted ammonia storage value is less than the maximum ammonia storage value, the predicted SCR temperature is less than the maximum SCR temperature, the predicted PF temperature is less than the maximum PF temperature, the predicted combustion noise level is less than the maximum combustion noise level, the predicted vehicle speed is greater than the minimum vehicle speed and less than the maximum vehicle speed, and the predicted vehicle jerk is greater than the minimum vehicle jerk and less than the maximum vehicle jerk.

[0093] In various implementations, satisfying the output constraints 352 relating to emissions values, exhaust system parameters, and drivability parameters may be considered in the cost determination. For example, the cost module 332 may determine the cost value for each of the possible sequences of corrections to the target values ​​230-246 based on the relationships between the predicted parameters and corresponding ones of the output constraints 352 discussed above.More specifically, the cost module 332 may determine the cost value for each of the possible sequences of corrections for the target values ​​230-246 based on the relationships between: the predicted engine exhaust NOx and the maximum engine exhaust NOx; the predicted engine exhaust soot and the maximum engine exhaust soot; the predicted ammonia storage value and the maximum ammonia storage value; the predicted SCR temperature and the maximum SCR temperature; the predicted PF temperature and the maximum PF temperature; the predicted combustion noise level and the maximum combustion noise level; the predicted vehicle speed and the minimum and maximum vehicle speeds; and the predicted vehicle jerk and the minimum and maximum vehicle jerk.

[0094] Referring to Fig. 4, an exemplary implementation of a prediction module 323 includes an engine exhaust NOx module 402, an engine exhaust soot module 404, a PF soot loading module 406, an SCR ammonia storage module 408, and an SCR / PF temperature module 410. The engine exhaust NOx module 402 predicts a nitrogen oxide (NOx) level in the exhaust gas produced by the engine 102, which, as mentioned above, may be referred to as engine exhaust NOx. The engine exhaust NOx module 402 outputs a signal 412 indicative of the predicted engine exhaust NOx level.

[0095] The engine exhaust NOx module 402 may predict the engine exhaust NOx level based on various engine parameters. These parameters may include an airflow rate into the cylinders of the engine 102, an oxygen concentration in the intake manifold 110, fuel injection timing and pressure, pilot injection amount and timing, and a temperature in the intake manifold 110, the engine coolant temperature, and / or the position of the swirl flap 120. The engine exhaust NOx module 402 may predict the engine exhaust NOx level using a model, equation, and / or lookup table related to one or more of the aforementioned engine exhaust NOx level parameters.

[0096] The engine exhaust soot module 404 predicts a soot level in the exhaust produced by the engine 102, which, as mentioned above, may be referred to as engine exhaust soot. The engine exhaust soot module 404 outputs a signal 414 indicative of the predicted engine exhaust soot level. The engine exhaust soot module 404 may predict the engine soot level based on various engine parameters. These parameters may include the air / fuel ratio of the engine 102, the total amount of recirculated exhaust gas provided to the engine 102, and / or fuel injection timing and pressure. The engine exhaust soot module 404 may predict the engine soot level using a model, equation, and / or lookup table related to one or more of the aforementioned engine soot level parameters.

[0097] The PF soot loading module 406 predicts an amount of soot deposition in the PF 138, which may be referred to as the PF soot loading. The PF soot loading module 406 outputs a signal 416 indicative of the predicted PF soot loading. The PF soot loading module 406 may predict the PF soot loading based on various parameters. These parameters may include the flow velocity of the engine exhaust NOx, the filtration efficiency of the PF 138, and the reaction rates taking place within the PF 138, such as the following two reactions: C + O2 = CO2; (1) and C + 2NO2 = CO2 + 2NO. (2)

[0098] The PF soot load module 406 may predict the PF soot load using a model, an equation, and / or a lookup table related to one or more of the aforementioned engine exhaust soot level parameters.

[0099] The SCR ammonia storage module 408 predicts a value of ammonia stored in the SCR catalyst 136. The SCR ammonia storage module 408 outputs a signal 418 indicative of the predicted ammonia storage value. The SCR ammonia storage module 408 may predict the engine exhaust soot level based on various parameters. These parameters may include an oxygen level in the exhaust entering the SCR catalyst 136, a NOx level in the exhaust entering the SCR catalyst 136, a mass flow rate of exhaust entering the SCR catalyst 136, a temperature of the exhaust entering the SCR catalyst 136, and / or a temperature of a substrate in the SCR catalyst 136. The SCR ammonia storage module 408 may predict the ammonia storage level using a model, an equation, and / or a lookup table that relates to one or more of the aforementioned ammonia storage level parameters.

[0100] The SCR / PF temperature module 410 predicts the temperature of the SCR catalyst 136 and the temperature of the PF 138. The SCR / PF temperature module 410 outputs a signal 420 indicative of the predicted SCR temperature and a signal 422 indicative of the predicted PF temperature. The SCR / PF temperature module 410 may predict the SCR and PF temperatures based on various parameters. These parameters may include the temperature of the exhaust gas entering the SCR catalyst 136, the mass flow rate of exhaust gas entering the SCR catalyst 136, the specific heat of the exhaust gas, the mass of substrates in the catalyst 136 and PF 138, and the specific heat of those substrates. The SCR / PF temperature module 410 may predict the SCR and PF temperatures using a model, equation, and / or lookup table related to one or more of the aforementioned SCR and PF temperature parameters.

[0101] The exemplary implementation of the prediction module 323 shown in Fig. 4, further includes a combustion noise module 424 and a drivability module 426. The combustion noise module 424 predicts a noise level due to the combustion of the fuel / air mixture provided to the cylinders of the engine 102. The combustion noise module 424 outputs a signal 428 indicative of the predicted combustion noise level. The combustion noise module 424 may predict the combustion noise level based on various engine parameters. These parameters may include engine speed, intake air mass flow rate, fuel injection timing, the number of fuel injections per combustion event, and / or the amount of fuel injected during each injection.The engine exhaust soot module 404 may predict the combustion noise level using a model, equation, and / or lookup table that relates to one or more of the aforementioned engine exhaust soot level parameters.

[0102] The drivability module 426 predicts drivability parameters, including vehicle speed and vehicle jerk. The drivability module 426 outputs a signal 430 indicative of the predicted vehicle speed and a signal 432 indicative of the predicted vehicle jerk. The drivability module 426 may also predict the amount of torque produced by the engine 102 and output a signal (not shown) indicative of the predicted torque output of the engine 102. The drivability module 426 may predict vehicle speed and vehicle jerk based on various engine parameters. These parameters may include the current vehicle speed, engine speed, intake air mass flow rate, fuel injection timing, the number of fuel injections per combustion event, and / or the amount of fuel injected during each injection.The engine exhaust soot module 404 may predict vehicle speed and vehicle jerk using a model, equation, and / or lookup table that relates to one or more of the aforementioned vehicle speed and vehicle jerk parameters.

[0103] These parameters, which are used to predict the engine outlet NOx level, the engine outlet soot level, the PF soot load, the ammonia storage level, the SCR temperature, the PF temperature, the combustion noise level, the vehicle speed, and the vehicle jerk, may be included in the exogenous inputs 328 and / or feedback inputs 330. Alternatively, these parameters may be included in the responses of the engine 102, which are predicted based on the possible sequences of the setpoints 230-246, the exogenous inputs 328, and the feedback inputs 330 using the model 324.

[0104] With reference to Fig. 5, an example method for controlling the throttle valve 112, the swirl flap 120, the intake cam phaser 148, the exhaust cam phaser 150, the wastegate 162 (and thus the turbocharger), the EGR valves 170 and 171, the EGR cooler bypass valve 176, the spark timing, the fueling, and the number of cylinders enabled / disabled using MPC (model predictive control) begins at 502. At 504, the propulsion torque arbitration module 214 determines the propulsion torque request 222. At 506, the torque conversion module 228 converts the propulsion torque request 222 to the base torque request 308 or another suitable torque type for use by the MPC module. around.

[0105] At 508, the reference value module 368 determines the reference values ​​340. As discussed above, the target value module 368 may determine the reference values ​​340 based on the propulsion torque request 222 and / or the base torque request 308. At 510, the sequence determination module 316 determines possible sequences of corrections for the target values ​​230-246.

[0106] At 512, the prediction module 323 predicts parameters for each of the possible sequences of corrections to the setpoints 230-246. For example, the prediction module 323 may use linear physics-based models to predict the emissions levels, exhaust system parameters, combustion noise levels, and drivability parameters.More specifically, based on a possible sequence of corrections for the setpoints 266-270, the exogenous inputs 328, and the feedback inputs 330 using the physics-based model, the prediction module 323 may generate a sequence of predicted engine outlet NOx values ​​for the N control loops, a sequence of predicted engine outlet soot values ​​for the N control loops, a sequence of predicted PF soot loading for the N control loops, a sequence of predicted ammonia storage values ​​for the N control loops, a sequence of predicted SCR temperatures for the N control loops, a sequence of predicted PF temperatures for the N control loops, a sequence of predicted combustion noise levels for the N control loops, a sequence of predicted vehicle speeds for the N control loops, and a sequence of predicted vehicle jerks for the N Create control loops.

[0107] At 514, the cost module 332 determines the costs for the possible sequences of corrections for the target values ​​230-246. For example, the cost module 332 may determine the costs for a possible sequence of corrections for the target values ​​230-246 based on the equation: Costs=∑i=1N[PFi+wCN∗PCNi], depending on the actuator constraints 348 and / or the output constraints 352, as discussed above.

[0108] At 516, the selection module 344 selects one of the possible sequences of corrections for the target values ​​230-246 based on the cost of the possible sequences. For example, the selection module 344 may select the one of the possible sequences with the lowest cost. The selection module 344 may therefore select the one of the possible sequences that best achieves the base torque request 308 while meeting target emissions and drivability objectives and maximizing fuel efficiency. Instead of, or in addition to, determining possible sequences of corrections for the target values ​​230-246 at 510 and determining the cost for each of the sequences at 514, the MPC module 312 may identify a sequence of possible corrections for the target values ​​with the lowest cost using convex optimization techniques, as discussed above.

[0109] At 518, the MPC module 312 determines whether the sequence selected from among the possible sequences satisfies the actuator constraints 348 and the output constraints 352. If the sequence selected from among the possible sequences satisfies the actuator constraints 348 and the output constraints 352, the method continues at 520. Otherwise, the method continues at 522, where the MPC module 312 selects the second-lowest-cost sequence among the possible sequences. The method then returns to 518. In this way, the lowest-cost sequence that satisfies the actuator constraints 348 and the output constraints 352 is applied.

[0110] At 520, the first conversion module 248 converts the wastegate target opening range 230 to the target duty cycle 250 to be applied to the wastegate 162, and the second conversion module 252 converts the throttle target opening range 232 to the target duty cycle 254 to be applied to the throttle valve 112. Also at 520, the fourth conversion module 256 converts the HP EGR target opening range 234 to the target duty cycle 258 to be applied to the HP EGR valve 170. Also at 520, the fourth conversion module 256 converts the LP EGR target opening range 235 to the target duty cycle 259 to be applied to the LP EGR valve 171. The fifth conversion module may also convert the intake cam and exhaust cam phaser desired angles 236 and 238 into the intake and exhaust desired duty cycle to be applied to the intake and exhaust cam phasers 148 and 150, respectively.

[0111] At 524, the throttle actuator module 116 controls the throttle valve 112 to achieve the desired throttle opening range 232. For example, at the desired duty cycle 254, the throttle actuator module 116 may apply a signal to the throttle valve 112 to achieve the desired throttle opening range 232. At 524, the swirl actuator module 121 controls the swirl flap 120 to achieve the desired swirl flap opening range 233, and the phaser actuator module 158 controls the intake and exhaust cam phasers 148 and 150 to achieve the desired intake cam and exhaust cam phaser angles 236 and 238, respectively.

[0112] Also at 524, the EGR actuator module 172 controls the EGR valves 170 and 171 to achieve the HP and LP EGR opening ranges 234 and 235, and the boost actuator module 164 controls the wastegate 162 to achieve the wastegate opening range 230. For example, the EGR actuator module 172 may apply signals to the EGR valves 170 and 171 at target duty cycles 258 and 259, respectively, to achieve the EGR opening ranges 234 and 235, respectively, and the boost actuator module 164 may apply a signal to the wastegate 162 at target duty cycle 250 to achieve the wastegate opening range 230.Also at 524, the ignition actuator module 126 controls ignition timing based on the desired ignition timing 240, the cylinder actuator module 119 controls cylinder activation and deactivation based on the desired number of cylinders 242, and the fuel actuator module 124 controls fueling based on the desired fueling parameters 244. Also at 524, the bypass actuator module 178 controls the EGR cooler bypass valve 176 to achieve the desired bypass opening range 246. The method may end at 526. Alternatively, . Fig. 5 represent a control loop, and control loops can be executed at a predetermined rate.

[0113] Spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.) are described using various terms, including "connected," "interlocked," "coupled," "adjacent," "beside," "on top of," "above," "below," and "disposed." Unless explicitly described as "direct," a relationship may be a direct relationship when a relationship is described between a first and second element in the above disclosure if no other intervening elements are present between the first and second elements, but may also be an indirect relationship if one or more intervening elements (either spatial or functional) are present between the first and second elements.As used herein, the phrase "at least one of A, B, and C" should be understood to mean a logic (A OR B OR C), using a non-exclusive logical OR, and should not be understood to mean "at least one of A, at least one of B, and at least one of C."

[0114] In this application, including the definitions below, the term "module" or the term "controller" may be replaced with the term "circuit" where appropriate. The term "module" may refer to, be part of, or include: an application-specific integrated circuit (ASIC); a digital, analog, or mixed analog / digital discrete circuit; a digital, analog, or mixed analog / digital integrated circuit; a combinational logic circuit; a field-programmable gate array (FPGA); a processor (shared, dedicated, or group) that executes code; memory (shared, dedicated, or group) that stores code executed by a processor; other suitable hardware components that provide the described functionality; or a combination of some or all of the above, such as in a system-on-chip.

[0115] The module may also include one or more interface circuits. In some examples, the interface circuits may include wired or wireless interfaces connected to a local area network (LAN), the Internet, a wide area network (WAN), or combinations thereof. The functionality of the modules mentioned in this disclosure may be distributed among multiple modules connected to interface circuits. For example, multiple modules may allow for load balancing. In another example, a server module (e.g., remote server or cloud) may assume certain functions of a client module.

[0116] The term "code," as used above, may include software, firmware, and / or microcode, and may refer to programs, routines, functions, classes, data structures, and / or objects. The term "shared processor circuitry" refers to a single processor circuitry that executes some or all of the code from multiple modules. The term "grouped processor circuitry" refers to a processor circuitry that, in combination with additional processor circuitry, executes some or all of the code from multiple modules. References to multiple processor circuitry include multiple processor circuitry on discrete dies, multiple processor circuitry on a single die, multiple cores on a single processor circuitry, multiple threads of a single processor circuitry, or a combination of the above.The term "shared memory circuit" refers to a single memory circuit that stores specific or complete code from multiple modules. The term "grouped memory circuit" refers to a memory circuit that, in combination with additional memory, stores specific or complete code from multiple modules.

[0117] The term "memory circuit" is subordinate to the term "computer-readable medium." As used herein, the term "computer-readable medium" does not refer to transient electrical or electromagnetic signals propagated in a medium (e.g., in the case of a carrier wave); the term "computer-readable medium" is therefore to be understood as tangible and non-transitory. Non-limiting examples of a non-transitory tangible computer-readable medium include non-volatile memory circuits (e.g., flash memory circuits, erasable programmable read-only memory (ROM) circuits, or mask ROM circuits), volatile memory circuits (e.g., static or dynamic RAM circuits), magnetic storage media (e.g., analog or digital magnetic tape or a hard disk drive), and optical storage media (e.g., CD, DVD, or Blu-ray).

[0118] The devices and methods described in this application may be implemented, in part or in full, using a dedicated computer configured to perform specific computer program functions. The functional blocks, flowchart components, and elements described above serve as software specifications that can be implemented into computer programs by appropriately trained technicians or programmers.

[0119] The computer programs include processor-executable instructions stored on at least one non-transitory tangible computer-readable medium. The computer programs may also include stored data or be based on stored data. The computer programs may include a Basic Input Output System (BIOS) that interacts with the hardware of the special-purpose computer, device drivers that interact with specific devices of the special-purpose computer, one or more operating systems, user applications, background services, background applications, etc.

[0120] The computer programs may include: (i) descriptive text that is parsed, such as HTML (hypertext markup language) or XML (extensible markup language), (ii) assembly code, (iii) object code created from source code by a compiler, (iv) source code for execution by an interpreter, (v) source code for compilation and execution by a just-in-time compiler, etc. By way of example only, source code may be written using the syntax of languages ​​such as C, C++, C#, Objective C, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl, Pascal, Curl, OCaml, Javascript®, HTML5, Ada, ASP (active server pages), PHP, Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, Visual Basic®, Lua and Python®.

Claims

[1] Method comprising: Generating a setpoint value for an actuator of a motor (102); Generating a setpoint for another actuator of the motor (102); Generate a set of possible corrections for each setpoint; predicting an operating parameter for each set of possible corrections, wherein the predicted operating parameter includes an emissions value and / or an operating parameter of an exhaust system (132); Determine the costs for each set of possible corrections; Selecting a set of possible corrections from the multiple sets of possible corrections based on cost; Determine whether the predicted operating parameter for the selected set satisfies a constraint; Adjusting the setpoints using the possible corrections of the selected set if the predicted operating parameter satisfies the constraint; and Controlling the actuator of the motor (102) based on the adjusted setpoint. [2] The method of claim 1, further comprising: Predicting a combustion noise level for the set of possible corrections; and Determine the cost of the set of possible corrections to the target values ​​based on the predicted combustion noise level. [3] The method of claim 1, wherein the predicted operating parameter includes a nitrogen oxide level in the exhaust gas produced by the engine (102). [4] The method of claim 1, wherein the predicted operating parameter includes a soot level in the exhaust gas produced by the engine (102). [5] The method of claim 1, wherein the predicted operating parameter includes an amount of soot deposition in a particulate filter (138) of the exhaust system (132). [6] The method of claim 1, wherein the predicted operating parameter includes an ammonia value stored in an SCR (selective catalytic reduction) catalyst (136) of the exhaust system (132). [7] The method of claim 1, wherein the predicted operating parameter includes a temperature of an SCR (selective catalytic reduction) catalyst (136) in the exhaust system (132). [8] The method of claim 1, wherein the predicted operating parameter includes a temperature of a particulate filter (138) in the exhaust system (132). [9] The method of claim 1, wherein the predicted operating parameter further includes a speed of a vehicle driven by the engine (102). [10] The method of claim 1, wherein the predicted operating parameter further includes a jerk of a vehicle driven by the engine (102).

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