DE102015103622B4 - Model prediction method for internal combustion engines with spark ignition - Google Patents

Abstract

An engine control method for a vehicle (102), comprising: generating a first torque request (265) for a spark ignition engine (100) based on driver input (404); converting the first torque request (265) to a second torque request (308) (408); using a model predictive control (MPC) module (312), determining a set of target values (266-270) based on the second torque request (308), a model of the engine (102) and a matrix of dimensions (m + n) times (m + n), where n is an integer greater than zero that is equal to a number of lower bounds used in determining the set of target values (266-270), and m is an integer greater than zero that is equal to a number of constraints used in determining the set of target values (266-270) other than the lower limit constraints (416); andcontrolling an opening (278) of a throttle valve (112) based on a first one (267) of the target values (266-270) (428, 432); controlling an opening (274) of a wastegate valve (162) of a turbocharger (160-1, 160-2) based on a second (266) of the target values (266-270) (428, 432); controlling opening (282) of an EGR valve (170) based on a third (268) of the target values (266 -270) (428, 432); and controlling an intake valve phasing (269) of an intake cam phaser (148) and an exhaust valve phasing (270) of an exhaust cam phaser (150) based on a fourth (269) and a fifth (270) of the target values (266), respectively -270) (428, 432).

Description

The present disclosure relates to internal combustion engines and, more particularly, to engine control methods for vehicles.

Internal combustion engines burn a mixture of air and fuel within cylinders to drive pistons, which creates drive torque. Air flow into the engine is regulated via a throttle. More specifically, the throttle adjusts a throttle area, which increases or decreases air flow into the engine. As the throttle area increases, air flow into the engine increases. A fuel control system adjusts the rate at which fuel is injected to provide a desired air / fuel mixture to the cylinders and / or to achieve a desired torque output. Increasing the amount of air and fuel provided to the cylinders increases the torque output of the engine.

In positive-ignition engines, an ignition spark initiates the combustion of an air / fuel mixture provided for the cylinders. In compression ignition engines, the compression in the cylinders burns the air / fuel mixture provided for the cylinders. Ignition timing and air flow can be the primary mechanisms for adjusting the torque output of spark ignition engines, while fuel flow can be the primary mechanism for adjusting the torque output of compression ignition engines.

Engine control systems have been developed to control engine output torque to achieve a desired torque. However, conventional engine control systems do not control engine output torque as precisely as desired. Furthermore, conventional engine control systems do not provide a quick response to control signals or coordinate engine torque control between various devices that affect engine output torque.

The US 7 398 149 B2 discloses a control method for an exhaust gas turbocharger and exhaust gas recirculation internal combustion engine that uses model prediction to control exhaust gas supply and fresh air supply into the engine. More precisely, among other things, the inlet and outlet side partial pressures of the fresh air and the exhaust gas are recorded and controlled via the model prediction. The phase position of the inlet and outlet valves is not controlled.

From the US 2006/0 137 347 A1 a method of controlling a diesel engine using model prediction is known. Both the air supply and the fuel supply are controlled, taking into account exhaust gas recirculation and turbocharger operation. A control of the opening and closing positions of the inlet and outlet valves via the model prediction is not disclosed.

The US 2011/010 073 A1 discloses engine control using model prediction. The multivariate control unit used to accelerate the adaptation of the control is to be assigned data in advance as a specification. Examples of variables to be controlled are fuel injection, engine brake control, exhaust gas treatment control, exhaust gas recirculation control, and turbocharger control. Nothing is said about the control of inlet and outlet valve phase positions via model prediction.

It is the object of the invention to provide an improved engine control method for a vehicle with a spark ignition engine that uses model prediction.

This object is achieved by a method with the features of claim 1.

Advantageous embodiments are specified in the dependent claims.

• 1 ein Funktionsblockschaltbild eines beispielhaften Kraftmaschinensystems gemäß der vorliegenden Offenbarung ist;
• 2 ein Funktionsblockschaltbild eines beispielhaften Kraftmaschinensteuersystems gemäß der vorliegenden Offenbarung ist;
• 3 ein Funktionsblockschaltbild eines beispielhaften Luftsteuermoduls gemäß der vorliegenden Offenbarung ist; und
• 4 ein Flussdiagramm umfasst, das ein beispielhaftes Verfahren zum Steuern eines Drosselventils, einer Einlassventil- und einer Auslassventil-Phasenlageneinstellung, eines Ladedruckregelventils und eines Abgasrückführungs-Ventils (AGR-Ventils) unter Verwendung einer Modellvorhersagesteuerung gemäß der vorliegenden Offenbarung zeigt.

The present disclosure will become more fully understood from the detailed description and accompanying drawings, in which:

• 1 FIG. 3 is a functional block diagram of an exemplary engine system in accordance with the present disclosure;
• 2 FIG. 3 is a functional block diagram of an exemplary engine control system in accordance with the present disclosure;
• 3 Figure 3 is a functional block diagram of an exemplary air control module in accordance with the present disclosure; and
• 4th comprises a flowchart showing an exemplary method for controlling a throttle valve, intake valve and exhaust valve phasing, wastegate and exhaust gas recirculation (EGR) valve using model predictive control in accordance with the present disclosure.

In the drawings, reference numbers may be reused to identify similar and / or identical elements.

An engine control module (ECM) controls torque output of an engine. More specifically, the ECM controls actuators of the engine each based on target values determined based on a requested torque amount. For example, the ECM controls intake camshaft phasing and exhaust camshaft phasing based on the target intake phaser angle and the target exhaust phaser angle, a throttle valve based on a target throttle opening, an exhaust gas recirculation (EGR) valve based on a Target EGR port and a turbocharger wastegate based on a target wastegate duty cycle.

The ECM could individually determine the target values using multiple single-input-single-output (SISO) controllers, such as proportional-integral-differential (PID) controllers. However, when multiple SISO controllers are used, the target values can be set to maintain system stability at the expense of possible fuel consumption reductions. In addition, calibration and design of each SISO controller can be costly and time consuming.

The ECM of the present disclosure generates the target values using model predictive control (MPC). The ECM identifies possible sets of target values based on an engine torque request. The ECM determines predicted parameters for each of the possible sentences. The ECM determines costs associated with the use of each of the possible rates based on the rates of predicted parameters. The ECM can choose the one of the lowest cost possible that meets the constraints. The constraints may include, for example, upper and lower limits for the predicted parameters, upper and lower limits for the target values, and / or other constraints. The ECM sets the target values for controlling the engine actuators using the target values of the selected possible set.

With reference to 1 Figure 3 is a functional block diagram of an exemplary engine system 100 shown. The engine system 100 includes an engine 102 based on a driver input from a driver input module 104 combusting an air / fuel mixture to produce drive torque for a vehicle. The power machine 102 may be a gasoline spark ignition internal combustion engine.

Through a throttle valve 112 gets air into an intake manifold 110 sucked in. The throttle valve can only be used as an example 112 a throttle valve with a rotatable plate. An engine control module (ECM) 114 controls a throttle actuator module 116 that the opening of the throttle valve 112 regulated to the amount of going into the intake manifold 110 to control sucked air.

Air from the intake manifold 110 is in cylinder of the engine 102 sucked in. Although the prime mover 102 may include multiple cylinders, a single representative cylinder is for purposes of illustration 118 shown. The engine can only be used as an example 102 2 , 3 , 4th , 5 , 6 , 8th , 10 and or 12th Include cylinder. The ECM 114 can be a cylinder actuator module 120 instruct to selectively deactivate some of the cylinders, which can improve fuel economy under certain engine operating conditions.

The power machine 102 can operate using a four stroke cycle. The four strokes described below can be referred to as the intake stroke, the compression stroke, the power stroke and the exhaust stroke. During each revolution of a crankshaft (not shown) take place inside the cylinder 118 two of the four bars. Thus two crankshaft revolutions are necessary for the cylinder 118 experiences every four bars.

During the intake stroke, a throttle valve is used 122 Air from the intake manifold 110 in the cylinder 118 sucked in. The ECM 114 controls a fuel actuator module 124 that controls fuel injection to achieve a target air / fuel ratio. Fuel can be in one central location or in multiple locations such as near the intake valve 122 from each of the cylinders into the intake manifold 110 be injected. In various implementations (not shown), fuel can be injected directly into the cylinders or into mixing chambers associated with the cylinders. The fuel actuator module 124 may stop the injection of fuel into cylinders that are deactivated.

The injected fuel mixes in the cylinder 118 with air and creates an air / fuel mixture. During the compression stroke, a piston (not shown) compresses within the cylinder 118 the air / fuel mixture. An ignition actuator module 126 puts a spark plug 128 in the cylinder 118 based on a signal from the ECM 114 under power, which ignites the air / fuel mixture. The timing of the spark can be specified compared to when the piston is in its topmost position, referred to as top dead center (TDC).

The ignition actuator module 126 can be controlled by a timing signal specifying how far before or after TDC the spark should be generated. Since piston position is directly related to crankshaft rotation, the operation of the ignition actuator module 126 be synchronized with the crankshaft angle. The creation of the spark can be referred to as an ignition event. The ignition actuator module 126 may have the ability to vary the spark timing for each ignition event. If the ignition timing has changed between a last ignition event and the next ignition event, the ignition actuator module may 126 vary the spark timing for a next ignition event. The ignition actuator module 126 may stop the provision of spark for deactivated cylinders.

During the power stroke, the combustion of the air / fuel mixture drives the piston away from TDC, thereby driving the crankshaft. The power stroke can be defined as the length of time between when the piston reaches TDC and when the piston reaches bottom dead center (BDC). During the exhaust stroke, the piston begins to move away from the BDC and pushes the byproducts of the combustion through an exhaust valve 130 out. The byproducts of combustion are removed from the vehicle via an exhaust system 134 pushed out.

The inlet valve 122 can through an intake camshaft 140 controlled while the exhaust valve 130 through an exhaust camshaft 142 can be controlled. In various implementations, multiple intake camshafts (including the intake camshaft 140 ) multiple intake valves (including the intake valve 122 ) for the cylinder 118 control and / or can control the inlet valves (including the inlet valve 122 ) multiple banks of cylinders (including the cylinder 118 ) Taxes. Similarly, multiple exhaust camshafts (including the exhaust camshaft 142 ) several exhaust valves for the cylinder 118 control and / or can control exhaust valves (including the exhaust valve 130 ) for multiple banks of cylinders (including the cylinder 118 ) Taxes. In various other implementations, the inlet valve 122 and / or the exhaust valve 130 controlled by devices other than camshafts such as camless valve actuators. The cylinder actuator module 120 can the cylinder 118 by disabling it by opening the inlet valve 122 and / or the exhaust valve 130 locks.

The time at which the inlet valve 122 may be opened with respect to piston TDC by an intake cam phaser 148 can be varied. The time at which the exhaust valve 130 may be opened with respect to piston TDC by an exhaust cam phaser 150 can be varied. A phase adjuster actuator module 158 can use the intake cam phaser 148 and the exhaust cam phaser 150 based on signals from the ECM 114 Taxes. If a variable valve lift is implemented (not shown), it can also be done by the phaser actuator module 158 being controlled.

The engine system 100 may include a turbocharger that has a hot turbine wheel 160-1 includes that by hot exhaust gases passing through the exhaust system 134 flow, is supplied with power. The turbocharger also includes a cold air compressor wheel 160-2 going through the turbine wheel 160-1 is driven. The compressor wheel 160-2 compresses air going into the throttle valve 112 got. In various implementations, a crankshaft driven supercharger (not shown) may supply air from the throttle valve 112 and compress the compressed air to the intake manifold 110 deliver.

An exhaust control valve 162 can allow exhaust gas to pass the turbine wheel 160-1 bypasses, thereby reducing the boost pressure (the amount of intake air compression) provided by the turbocharger. A boost pressure actuator module 164 can control the boost pressure of the turbocharger by opening the boost pressure control valve 162 controls. In various implementations, two or more turbochargers can be deployed and used by the boost pressure actuator module 164 be controlled.

An air cooler (not shown) can transfer heat from the compressed air charge to a cooling medium, such as engine coolant or air. An air cooler that cools the compressed air charge using engine coolant may be referred to as an intercooler. An air cooler that cools the compressed air charge using air can be referred to as a charge air cooler. The compressed air charge can heat z. B. on compression and / or components of the exhaust system 134 receive. Although the turbine wheel 160-1 and the compressor wheel 160-2 Shown separately for purposes of illustration, they may be attached to one another, placing intake air in close proximity to hot exhaust gas.

The engine system 100 can an exhaust gas recirculation valve (EGR valve) 170 include the optional exhaust gas to the intake manifold 110 redirects back. The EGR valve 170 can be located upstream of the turbine wheel 160-1 of the turbocharger. The EGR valve 170 can through an EGR actuator module 172 based on signals from the ECM 114 being controlled.

Using a crankshaft position sensor 180 a position of the crankshaft can be measured. Based on the crankshaft position, a rotational speed of the crankshaft (an engine speed) can be determined. Using an engine coolant temperature (ECT) sensor 182 a temperature of the engine coolant can be measured. The ECT sensor 182 can be inside the prime mover 102 or other locations where the coolant is circulated, such as a cooler (not shown).

Using a manifold absolute pressure (MAP) sensor 184 can be a pressure inside the intake manifold 110 be measured. In various implementations, engine vacuum may be the difference between ambient air pressure and the pressure within the intake manifold 110 is to be measured. Using a mass air flow (MAF) sensor 186 can be a mass flow rate of the into the intake manifold 110 flowing air can be measured. In different implementations, the MAF sensor 186 located in a housing that also contains the throttle valve 112 includes.

The throttle actuator module 116 can be done using one or more throttle position sensors (TPS) 190 the position of the throttle valve 112 monitor. Using an intake air temperature (IAT) sensor 192 can be an ambient temperature in the engine 102 sucked in air can be measured. In addition, the engine system 100 one or more other sensors 193 such as an ambient humidity sensor, one or more knock sensors, a compressor outlet pressure sensor and / or a throttle inlet pressure sensor, a wastegate position sensor, an EGR position sensor, and / or one or more other suitable sensors. The ECM 114 may use signals from the sensors to make control decisions for the engine system 100 hold true.

The ECM 114 can with a transmission control module 194 communicate to coordinate the shifting of gears in a transmission (not shown). For example, the ECM 114 decrease engine torque during a gear shift. The ECM 114 can with a hybrid control module 196 communicate to the operation of the prime mover 102 and an electric motor 198 to coordinate.

The electric motor 198 can also act as a generator and can be used to produce electrical energy for use by vehicle electrical systems and / or for storage in a battery. Different functions of the ECM 114 , the transmission control module 194 and the hybrid control module 196 be integrated in one or more modules.

Any system that varies an engine parameter can be referred to as an engine actuator. For example, the throttle actuator module 116 the opening of the throttle valve 112 adjust to achieve a target throttle area. The ignition actuator module 126 controls the spark plugs to achieve a target spark timing relative to piston TDC. The fuel actuator module 124 controls the fuel injectors to achieve target fueling parameters. The phase adjuster actuator module 158 can use the intake cam phaser and the exhaust cam phaser 148 and 150 control to achieve a target intake cam phaser angle or a target exhaust cam phaser angle. The EGR actuator module 172 can the EGR valve 170 control to achieve a target EGR opening area. The boost pressure actuator module 164 controls the boost pressure control valve 162 to achieve a target wastegate opening area. The cylinder actuator module 120 controls cylinder deactivation to achieve a target number of activated or deactivated cylinders.

The ECM 114 generates the target values for the engine actuators to cause the engine 102 generates a target engine output torque. As discussed below, the ECM generates 114 the target values for the engine actuators using model predictive control.

Well in 2 A functional block diagram of an exemplary engine control system is shown. An exemplary implementation of the ECM 114 includes a driver torque module 202 , an axle torque arbitration module 204 and a propulsion torque arbitration module 206 . The ECM 114 can be a hybrid optimization module 208 contain. It also contains the ECM 114 a reserves / loads module 220 , a torque request module 224 , an air control module 228 , an ignition control module 232 , a cylinder control module 236 and a fuel control module 240 .

The driver torque module 202 can be based on a driver input 255 from the driver input module 104 a driver torque request 254 determine. The driver input 255 can e.g. B. be based on a position of an accelerator pedal and on a position of a brake pedal. In addition, the driver input 255 based on a cruise control, which can be an adaptive cruise control system that varies the vehicle speed in order to maintain a predetermined following distance. The driver torque module 202 can store one or more characteristic curves of the accelerator pedal position to target torque and can, based on a selected one of the characteristic curves, the driver torque request 254 determine.

Axis torque arbitration module 204 arbitrates between the driver torque request 254 and other axle torque requirements 256 . The axle torque (the torque on the wheels) can be generated by various sources including an engine and / or an electric motor. For example, the axle torque requirements 256 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 against the road surface. Also, the axle torque requirements 256 receive a torque increase request to counter a negative wheel slip in which a tire of the vehicle slips in the other direction with respect to the road surface because the axle torque is negative.

Also, the axle torque requirements 256 Brake management requirements and vehicle overspeed torque requirements. The brake management requirements may decrease the axle torque to ensure that the axle torque does not exceed the ability of the brakes to hold the vehicle when the vehicle is stopped. Vehicle overspeed torque requests may decrease axle torque to prevent the vehicle from exceeding a predetermined speed. The axle torque requirements 256 can also be generated by vehicle stability control systems.

The axle torque arbitration module 204 gives based on the results of the arbitration between the received torque requests 254 and 256 a predicted torque request 257 and an instant torque request 258 out. As described below, the predicted torque request and the immediate torque request 257 and 258 from the axle torque arbitration module 204 optionally through other modules of the ECM 114 before they are used to control the engine actuators.

Generally speaking, the instant torque request 258 be an amount of the currently desired axle torque while the predicted torque request 257 an amount of axle torque that may be necessary in the short term. The ECM 114 controls the engine system 100 to get an axle torque equal to the immediate torque request 258 to create. However, different combinations of target values can result in the same axle torque. Thus, the ECM 114 adjust the target values so that a faster transition to the predicted one Torque requirement 257 is made possible, while the axle torque continues with the immediate torque request 258 is held.

In various implementations, the predicted torque request 257 based on the driver torque request 254 can be set. Under certain circumstances, such as when the driver torque request 254 causes wheel slip on an icy surface, the instant torque request 258 to less than the predicted torque request 257 can be set. In this case, a traction control system (not shown) can use the immediate torque request 258 request a reduction, the ECM 114 the engine torque output to the instantaneous torque output 258 decreased. However, the ECM leads 114 the reduction so that the engine system 100 the generation of the predicted torque request 257 can quickly resume as soon as the wheel slip stops.

Generally speaking, the difference between the immediate torque request 258 and the (generally higher) predicted torque request 257 can be referred to as a torque reserve. The torque reserve can increase the amount of additional torque (above the immediate torque request 258 ) represent that the engine system 100 can begin to generate with minimal delay. In order to increase or decrease the current axle torque with minimal delay, fast engine actuators are used. Fast engine actuators are defined as opposed to slow engine actuators.

Generally speaking, fast engine actuators can change axle torque faster than slow engine actuators. Slow actuators can respond more slowly to changes in their respective target values than fast actuators. A slow actuator can e.g. B. include mechanical components that require more time to move from one position to another in response to a change in a target value. In addition, a slow actuator can be characterized by the time it takes for the axle torque to start changing as soon as the slow actuator starts to implement the changed target value. In general, this time period is longer for slow actuators than for fast actuators. Also, even after the change has started, it may take longer for the axle torque to fully respond to a change in a slow actuator.

The ignition actuator module can only be used as an example 126 be a quick actor. Positive ignition engines can use fuels including e.g. B. Burn gasoline and ethanol by applying an ignition spark. In contrast, the throttle actuator module 116 be a slow actor.

For example, the ignition actuator module 126 as described above, if the ignition timing is changed between a last ignition event and the next ignition event, the ignition timing for a next ignition event will vary. In contrast, changes in throttle opening may take longer to affect engine output torque. The throttle actuator module 116 changes the throttle opening by changing the angle of the flap of the throttle valve 112 adapts. Thus there is a mechanical delay while the throttle valve is moving 112 moves from its previous position to a new position in response to the change when the target value to open the throttle valve 112 will be changed. In addition, air flow changes based on the throttle opening are subject to air transport delays in the intake manifold 110 . There is also increased air flow in the intake manifold 110 Realized only as an increase in engine output torque when the cylinder 118 receives additional air in the next intake stroke, compresses the additional air, and begins the power stroke.

Using these actuators as an example, this may include adjusting the throttle opening to a value that would enable the engine 102 the predicted torque request 257 generated, a torque reserve can be created. Meanwhile, the ignition timing may be based on the immediate torque request 258 be set that are smaller than the predicted torque request 257 is. Although the throttle opening creates enough air flow to keep the engine 102 the predicted torque request 257 is generated, the ignition timing is based on the immediate torque request 258 adjusted late (which reduces the torque). Thus, the engine output torque becomes equal to the immediate torque request 258 .

If additional torque is required, the ignition timing may be adjusted based on the predicted torque request 257 or a torque between the predicted Torque request and the immediate torque request 257 and 258 can be set. The ignition actuator module can 126 reset the ignition timing to an optimum value that enables the engine to operate 102 produces the full engine output torque that can be achieved when the airflow is already in place. Thus, the engine output torque can quickly match the predicted torque request 257 can be increased without experiencing delays from changing the throttle opening.

The axle torque arbitration module 204 can be the predicted torque request 257 and the instant torque request 258 to a propulsion torque arbitration module 206 output. In various implementations, the axle torque arbitration module 204 the predicted torque request and the immediate torque request 257 and 258 to the hybrid optimization module 208 output.

The hybrid optimization module 208 can determine how much torque is going through the prime mover 102 should be generated and how much torque should be generated by the electric motor 198 should be generated. The hybrid optimization module then gives 208 the modified predicted torque request and the modified immediate torque request 259 or. 260 to the propulsion torque arbitration module 206 out. In different implementations, the hybrid optimization module 208 in the hybrid control module 196 be implemented.

The predicted torque request and the immediate torque request made by the propulsion torque arbitration module 206 are received are converted from an axle torque area (torque on the wheels) into a propulsion torque area (torque on the crankshaft). This implementation can be performed before, after, as part of, or in place of, the hybrid optimization module 208 occur.

The propulsion torque arbitration module 206 arbitrates between propulsion torque requirements 290 containing the converted predicted torque requests and immediate torque requests. The propulsion torque arbitration module 206 generates an arbitrated predicted torque request 261 and an arbitrated instant torque request 262 . The arbitrated torque requests 261 and 262 can be generated by selecting a winning request from the received torque requests. Alternatively or additionally, the arbitrated torque requests may be generated by changing one of the received requests based on one or more other of the received torque requests.

The propulsion torque requirements 290 can e.g. B. Torque reductions for engine overspeed protection, torque increases to prevent stalling, and by the transmission control module 194 contain torque reductions requested to adapt to gear shifts. In addition, the propulsion torque requirements 290 result from a clutch fuel cutoff that reduces fuel output torque when the driver in a manual transmission vehicle depresses the clutch pedal to prevent engine spinning.

In addition, the propulsion torque requirements 290 include an engine shutdown request that may be initiated when a critical fault is detected. For example only, critical failures may include detection of vehicle theft, a stuck starter motor, electronic throttle control issues, and unexpected torque increases. In various implementations, the arbitration selects the engine shutdown request as the winning request when an engine shutdown request is present. If the engine shutdown request is present, the propulsion torque arbitration module may 206 as the arbitrated predicted torque request and as the arbitrated immediate torque request 261 and 262 Output zero.

In various implementations, an engine shutdown request may power the engine 102 simply switch off separately from the arbitration process. The propulsion torque arbitration module 206 may continue to receive the engine shutdown request so that e.g. B. suitable data can be fed back to other torque request devices. For example, all other torque requestors can be informed that they have lost the arbitration.

The reserves / loads module 220 receives the arbitrated predicted torque request and the arbitrated immediate torque request 261 and 262 . The reserves / loads module 220 can the arbitrated predicted torque request and the arbitrated immediate torque request 261 and 262 Adjust so that a torque reserve is created and / or that one or more loads are compensated. The reserves / loads module will respond 220 the adjusted predicted torque request and the adjusted immediate torque request 263 and 264 to the torque request module 224 out.

For example only, a catalyst light-off process or a cold start emissions reduction process may require retarded ignition timing. This means that the reserves / loads module 220 the adjusted predicted torque request 263 via the adapted immediate torque request 264 to generate a retarded spark for the cold start emission reduction process. In another example, the engine air / fuel ratio and / or the air mass flow may be varied directly, such as by intrusive diagnostic equivalence ratio tests and / or by re-purging the engine. Before beginning these processes, a torque reserve may be created or increased to quickly offset reductions in engine output torque resulting from the lean air / fuel mixture during these processes.

In addition, the reserves / loads module 220 create or increase a torque reserve in anticipation of a future load such as power steering pump operation or the engagement of an air conditioning compressor (A / C) compressor clutch. The reserve for engaging the A / C compressor clutch can be generated when the driver requests the air conditioning for the first time. The reserves / loads module 220 can adjust the predicted torque request 263 while it increases the adjusted immediate torque request 264 leaves unchanged in order to generate the torque reserve. When the A / C compressor clutch is then engaged, the reserves / loads module 220 the adapted immediate torque request 264 by the estimated load on the A / C compressor clutch.

The torque request module 224 receives the adjusted predicted torque request and the adjusted immediate torque request 263 and 264 . The torque request module 224 determines how the adjusted predicted torque request and the adjusted immediate torque request 263 and 264 can be achieved. The torque request module 224 can be engine type specific. For example, the torque request module 224 be implemented differently or use different control schemes for positive-ignition engines compared to compression-ignition engines.

In various implementations, the torque request module 224 define a boundary between modules that are common across all engine types and modules that are engine type specific. The engine types can e.g. B. include spark ignition and compression ignition. Modules before the torque request module 224 such as the propulsion torque arbitration module 206 may be common between engine types during the torque request module 224 and subsequent modules can be specific to the engine type.

The torque request module 224 determined based on the adjusted predicted torque request and the adjusted immediate torque request 263 and 264 an air torque request 265 . The air torque requirement 265 can be a braking torque. Braking torque can refer to a torque on the crankshaft under the current operating conditions.

Based on the air torque request 265 target values are determined for air flow control engine actuators. The air control module determines more precisely 228 based on the air torque request 265 a target wastegate opening area 266 , a target throttle area 267 , a target EGR opening area 268 , a target intake cam phaser angle 269 and a target exhaust cam phaser angle 270 . As discussed below, the air control module determines 228 the target wastegate opening area using model predictive control 266 , the target throttle area 267 , the target EGR opening area 268 , the target intake cam phaser angle 269 and the target exhaust cam phaser angle 270 .

The boost pressure actuator module 164 controls the boost pressure control valve 162 to get the target wastegate opening area 266 to reach. For example, a first implementation module 272 the target wastegate opening area 266 into a target duty cycle 274 implement that to the boost pressure control valve 162 should be created, and the boost pressure actuator module 164 based on the target duty cycle 274 a Signal to the boost pressure control valve 162 invest. In different implementations, the first implementation module 272 the target wastegate opening area 266 into a target wastegate position (not shown) and the target wastegate position into the target duty cycle 274 implement.

The throttle actuator module 116 controls the throttle valve 112 to get the target throttle area 267 to reach. For example, a second implementation module 276 the target throttle orifice area 267 into a target duty cycle 278 implement that to the throttle valve 112 should be created, and the throttle actuator module 116 based on the target duty cycle 278 a signal to the throttle valve 112 invest. In various implementations, the second implementation module 276 the target throttle orifice area 267 to a target throttle position (not shown) and the target throttle position to the target duty cycle 278 implement.

The EGR actuator module 172 controls the EGR valve 170 to the target EGR opening area 268 to reach. For example, a third implementation module 280 the target EGR opening area 268 into a target duty cycle 282 implement that to the EGR valve 170 should be created, and the EGR actuator module can 172 based on the target duty cycle 282 a signal to the EGR valve 170 invest. In various implementations, the third implementation module 280 the target EGR opening area 268 into a target EGR position (not shown) and the target EGR position to the target duty cycle 282 implement.

The phase adjuster actuator module 158 controls the intake cam phaser 148 to get the target intake cam phaser angle 269 to reach. In addition, the phase adjuster actuator module controls 158 the exhaust cam phaser 150 to get the target exhaust cam phaser angle 270 to reach. In various implementations, a fourth conversion module (not shown) can be included and convert the target intake cam phaser angle and the target exhaust cam phaser angle into a target intake duty cycle and a target exhaust duty cycle, respectively. The phase adjuster actuator module 158 can set the target intake duty cycle and the target exhaust duty cycle to the intake cam phaser and to the exhaust cam phaser 148 or. 150 invest. In various implementations, the air control module 228 determine a target overlap factor and an effective target displacement, and the phaser actuator module 158 can the intake cam phaser and the exhaust cam phaser 148 and 150 to achieve the target overlap factor and effective target displacement.

wobei APC eine APC ist, I ein Einlassventil-Phasenlageneinstellungswert ist, E ein Auslassventil-Phasenlageneinstellungswert ist, AF ein Luft/Kraftstoff-Verhältnis ist, OT eine Öltemperatur ist, und # eine Zahl aktivierter Zylinder ist. Diese Beziehung kann als eine Gleichung und/oder als eine Nachschlagetabelle verkörpert sein. Das Luft/Kraftstoff-Verhältnis (AF) kann das tatsächliche Luft/Kraftstoff-Verhältnis sein, wie es durch das Kraftstoffsteuermodul 240 berichtet wird.In addition, the torque request module 224 based on the predicted torque request and the immediate torque request 263 and 264 an ignition torque request 283 , a cylinder deactivation torque request 284 and a fuel torque request 285 produce. The ignition control module 232 may based on the ignition torque request 283 determine how much to retard the spark timing from an optimal spark timing (which reduces engine output torque). For example only, a torque relationship may be reversed to after a target spark timing 286 dissolve. For a given torque request (T _Req ), the target ignition timing (S _T ) 286 can be determined based on the following: $$\text{ST}={\text{f}}^{-1}\left({\text{T}}_{\text{Req}}\text{, APC}\text{, I.}\text{, E}\text{, AF}\text{, OT}\text{, \#}\right),$$

where APC is an APC, I is an intake valve phasing value, E is an exhaust valve phasing value, AF is an air / fuel ratio, OT is an oil temperature, and # is a number of activated cylinders. This relationship can be embodied as an equation and / or a look-up table. The air / fuel ratio (AF) may be the actual air / fuel ratio as determined by the fuel control module 240 is reported.

When the spark timing is adjusted to the optimal spark timing, the resulting torque can be as close as possible to a minimum spark advance for best torque (MBT spark timing). Best torque refers to the maximum engine output torque produced for a given airflow while the spark timing is advanced, while using a higher octane than a predetermined octane fuel and using stoichiometric fueling. The ignition timing at which this best occurs is referred to as an MBT ignition timing. For example, because of fuel quality (such as when lower octane fuel is used) and environmental factors such as ambient humidity and temperature, the optimal ignition timing may differ slightly from the MBT ignition timing. Thus, the engine output torque may be less than MBT at the optimal ignition timing. Just an example For example, a table of optimal ignition timing settings corresponding to various engine operating conditions may be determined during a calibration phase of the vehicle design, the optimal value being determined from a table based on the current engine operating conditions.

The cylinder deactivation torque request 284 can through the cylinder control module 236 used to set a target number of cylinders to be deactivated 287 to determine. In various implementations, a target number of cylinders to activate can be used. The cylinder actuator module 120 optionally enables and disables based on the target count 287 the valves of cylinders.

In addition, the cylinder control module 236 the fuel control module 240 instruct the supply of fuel to deactivated cylinders to stop; and the ignition control module 232 instruct to stop providing spark to deactivated cylinders. The ignition control module 232 may halt the provision of a spark to a cylinder once a fuel / air mixture already present in the cylinder has been burned.

The fuel control module 240 may be based on the fuel torque request 285 vary the amount of fuel provided to each cylinder. More specifically, the fuel control module 240 based on the fuel torque request 285 Target fueling parameters 288 produce. The target fueling parameters 288 can e.g. A target fuel mass, a target injection start timing, and a target fuel injection number.

During normal operation, the fuel control module 240 operate in an air conduction mode in which the fuel control module 240 seeks to maintain a stoichiometric air / fuel ratio by controlling fueling based on air flow. For example, the fuel control module 240 determine a target fuel mass that will provide stoichiometric combustion when combined with a present mass of air per cylinder (APC).

3 Figure 3 is a functional block diagram of an example implementation of the air control module 228 . Now referring to the 2 and 3 can the air torque request 265 be a braking torque as discussed above. A torque conversion module 304 sets the air torque request 265 from braking torque to base torque. The torque request resulting from the conversion into the base torque is called a base air torque request 308 designated.

Base torques may refer to a torque on the crankshaft that occurs during operation of the engine 102 is generated on a dynamometer while the prime mover 102 is warm and the engine 102 no torque loads are imposed by accessories such as an alternator and the A / C compressor. The torque conversion module 304 can the air torque request 265 z. B. using a characteristic curve or a function that relates the braking torques to base torques into the base air torque request 308 implement. In various implementations, the torque conversion module 304 the air torque requirement 265 convert to another suitable type of torque, such as an indexed torque. Indexed torque may refer to torque on the crankshaft attributable to work generated via combustion within the cylinders.

An MPC module 312 generates the target values 266-270 using MPC (Model Predictive Control) to calculate the base air torque requirement 308 to reach. The MPC module 312 includes a state estimator module 316 and an optimization module 320 .

und $$y\left(k\right)=\text{Cx}\left(k\right),$$

wobei keine k-te Steuerschleife ist, x(k) ein Vektor mit Einträgen ist, die Zustände der Kraftmaschine 102 für die k-te Steuerschleife angeben, x(k-1) der Vektor x(k) aus der (t-1)-ten Steuerschleife ist, A eine Matrix ist, die konstante Werte umfasst, die auf der Grundlage von Charakteristiken der Kraftmaschine 102 kalibriert sind, B eine Matrix ist, die konstante Werte umfasst, die auf der Grundlage von Charakteristiken der Kraftmaschine 102 kalibriert sind, u(k-1) ein Vektor von enthaltenen Einträgen für die Zielwerte 266-270 ist, die während der letzten Steuerschleife verwendet werden, y(k) eine Linearkombination des Vektors x(k) ist, und C eine Matrix ist, die konstante Werte umfasst, die auf der Grundlage von Charakteristiken der Kraftmaschine 102 kalibriert sind. Ein oder mehrere Zustandsparameter können auf der Grundlage von gemessenen oder geschätzten Werten für diese Parameter angepasst werden, die gemeinsam durch Rückkopplungseingänge 330 veranschaulicht sind.The state estimator module 316 determines states for a control loop based on a mathematical model of the engine 102 , the states of the engine from a previous (eg last) control loop and the target values 266-270 from the previous control loop. For example, the state estimator module 316 determine the states for a control loop based on the relationships: $$\text{x}\left(k\right)=\text{Ax}\left(k-1\right)+\text{Bu}\left(k-1\right)$$

and $$y\left(k\right)=\text{Cx}\left(k\right),$$

where is not a kth control loop, x (k) is a vector with entries, the states of the prime mover 102 for the kth control loop, x (k-1) is the vector x (k) from the (t-1) th control loop, A is a matrix comprising constant values based on characteristics of the engine 102 are calibrated, B is a matrix comprising constant values based on characteristics of the engine 102 are calibrated, u (k-1) a vector of contained entries for the target values 266-270 used during the final control loop, y (k) is a linear combination of the vector x (k), and C is a matrix including constant values based on characteristics of the engine 102 are calibrated. One or more state parameters can be adjusted based on measured or estimated values for these parameters that are shared by feedback inputs 330 are illustrated.

1. (1) Verwende obige Gleichungen und Rückkopplungseingänge 330, um Schätzungen der Zustände der Kraftmaschine 102 zu Zeitpunkt k zu erhalten;
2. (2) Berechne optimale Werte für die Zielwerte 266-270 für den Zeitpunkt k, um eine Kostenfunktion während des Zeitraums von dem Zeitpunkt k bis zu einem künftigen Zeitpunkt k+p zu minimieren; und
3. (3) Stelle die Zielwerte 266-270 auf die berechneten Optimalwerte nur für den Zeitpunkt k+1 ein. Kehre dann zu (1) zurück.

The functions provided by the MPC module 312 can generally be described as follows. For k = 1, ..., N, where N is an integer greater than one, do the following:

1. (1) Use the above equations and feedback inputs 330 to get estimates of the states of the prime mover 102 to get at time k;
2. (2) Calculate optimal values for the target values 266-270 for the time k to minimize a cost function during the period from the time k to a future time k + p; and
3. (3) Set the target values 266-270 on the calculated optimal values only for time k + 1. Then return to (1).

The period between k and k + p relates to a forecast horizon.

The cost function is the behavior criterion to be minimized in the case of the optimal value control problem defined over the forecast horizon at each time step. This function reflects the desired tax target specifications. This can, for example, be the sum of different terms that correspond, for example, to tracking errors Σ _i | (u (i) -u _ref (i)) | ² for the manipulated variables to keep track of any reference positions, Σ _i | (y (i) -y _ref (i)) | ² for the controlled variables to keep track of any desired setpoint values, for example control effort Σ _i | (u (i)) ² or Σ _i | (Δu (i)) | ² , and a penalty term for a restriction violation. More generally, the cost function depends on manipulated variables u and their deviations / variations Δu, the controlled variable y and a constraint violation penalty variable ε. The target values 266-270 can be called manipulated variables and are named with the variable u. Predicted parameters can be referred to as controlled variables and can be named using the variable y.

An actuator restriction module 360 ( 2 ) can have actuator restrictions 348 for the target values 266-270 to adjust. For example, the actuator restriction module 360 an actuator restriction for the throttle valve 112 , an actuator restriction for the EGR valve 170 , an actuator restriction for the boost pressure control valve 162 , an actuator restriction for the intake cam phaser 148 and an actuator limitation for the exhaust cam phaser 150 to adjust.

The actuator restrictions 348 for the target values 266-270 may include a maximum value for an associated target value and a minimum value for that target value. In general, the actuator restriction module 360 the actuator restrictions 348 set to specified operating ranges for the assigned actuators. The actuator restriction module 360 the actuator restrictions 348 generally to predetermined operating ranges for the throttle valve 112 , for the EGR valve 170 , for the boost pressure control valve 162 , for the intake cam phaser 148 and for the exhaust cam phaser 150 to adjust. However, the actuator restriction module 360 Optionally one or more of the actuator restrictions in some circumstances 348 to adjust.

An output restriction module 364 ( 2 ) may have output restrictions 352 for the controlled variables (y). The spending restrictions 352 for the controlled variable can include a maximum value for this controlled variable and a minimum value for this controlled variable. The output restriction module 364 can the issue restrictions 352 each generally set to predetermined ranges for the associated controlled variables. However, the output restriction module 364 in some circumstances, one or more of the issuance restrictions 352 vary.

A reference module 368 (please refer 2 ) generates reference values 356 for the target values 266-270 . The reference values 356 include for each of the target values 266-270 a reference. In other words, the reference values include 356 a reference wastegate opening area, a reference throttle opening area, a reference EGR opening area, a reference intake cam phaser angle, and a reference exhaust cam phaser angle. The reference module 368 can use the reference values 356 z. B. based on the air torque request 265 , the base air torque requirement 308 and / or determine one or more other suitable parameters.

irgendwelche Optimierungsvariablen darstellt, können quadratische Funktionen von x in die folgende Form gebracht werden: $$\frac{1}{2}{x}^{T}Qx-h^{T}x+Konstante,$$

wobei Q eine konstante symmetrische n x n Matrix ist, Constant ein konstanter Wert ist, und $$h\in {ℝ}^n$$

ein konstanter Vektor ist. Lineare Beschränkungen liegen in folgender Form vor $$Cx\le b,$$

wobei C eine Konstantenmatrix ist, und b ein Konstantenvektor ist.For example, the optimization module 320 the target values 266-270 using a quadratic programming (QP) solver such as a Dantzig QP solver. A QP equation solver solves an optimization problem with a quadratic cost function under inequality constraints. For example, if the vector $$x={ℝ}^n$$

represents any optimization variables, quadratic functions of x can be expressed in the following form: $$\frac{1}{2}{x}^{T}Qx-H^{T}x+KOnstante,$$

where Q is a constant symmetric nxn matrix, Constant is a constant value, and $$H\in {ℝ}^n$$

is a constant vector. Linear constraints take the following form $$\mathrm{C.}x\le b,$$

where C is a constant matrix and b is a constant vector.

$$y\left(k\right):=\left(y1\left(k\right)\text{,}\dots {\text{,yn}}_y\left(k\right)\right)\text{,}$$

und $$\mathrm{\Delta }\text{ui}\left(\text{k}\right)=\left(u1\left(k\right)\text{,}\dots \text{,}u{n}_u\left(k\right)\right)\text{,}$$

wobei i eine ganze Zahl zwischen 1 und n_u ist.The following is described in terms of nu with reference to the number of target values (e.g., 5 in the above example) and ny with reference to the number of controlled variables. $$u\left(k\right)=\left(u1\left(k\right),...,u{n}_u\left(k\right)\right),$$

$$y\left(k\right):=\left(y1\left(k\right)\text{,}...{\text{, yn}}_y\left(k\right)\right)\text{,}$$

and $$\mathrm{\Delta }\text{ui}\left(\text{k}\right)=\left(u1\left(k\right)\text{,}...\text{,}u{n}_u\left(k\right)\right)\text{,}$$

where i is an integer between 1 and n _u .

The tax problem to be solved can be written as:

unter den Beschränkungen $$\begin{array}{l}{y}_{min,i}-\in v_y\le y_i\left(k\right)\le y_{max,i}+\in v_y\text{,}\\ \text{wobei i}=\text{1}\text{,}\dots {\text{,n}}_y\text{ und k}=\text{1}\text{,}\dots \text{,}p\text{,}\end{array}$$

$$\begin{array}{l}{u}_{min.i}-\in v_u\le u_i\left(k\right)\le u_{max,i}+\in v_u,\\ \text{wobei i=1}\text{,}\dots {\text{,n}}_u\text{ und }k=\mathrm{1,}\dots ,p-\mathrm{1,}\text{ und}\end{array}$$

$$\begin{array}{l}\Delta u_{min,i}-\in v_{\mathrm{\Delta }\text{u}}\le \mathrm{\Delta }{\text{u}}_i\left(k\right)\le \mathrm{\Delta }{\text{u}}_{max,i}+\in v_{\mathrm{\Delta }\text{u}},\\ \text{wobei i}=\text{1}\text{,}\dots {\text{,n}}_u\text{ und k}=\mathrm{1,}\dots ,p-\mathrm{1,}\end{array}$$

wo, wie oben beschrieben, $$y\left(k\right)=Cx\left(k\right),$$

während erfüllt ist $$x\left(k\right)=\text{Ax}\left(k-1\right)+\text{Bu}\left(\text{k}-1\right).$$

w_Δu, w_u und w_y sind vorbestimmte Gewichtungswerte, die positiv sind. v_Δu, v_u und v_y sind vorbestimmte weiche Beschränkungswerte, die größer als oder gleich Null sind. Die vorbestimmen Beschränkungswerte können zum Beispiel auf Null eingestellt werden, um harte Beschränkungen an dem jeweiligen Parameter zu bewirken. Werte mit dem tiefgestellten min und max benennen obere und untere Beschränkungen für die jeweiligen Parameter.Minimize: $$\begin{array}{l}J\left(\Delta u,\in \right):=p{\in }^2+{\displaystyle {\sum }_{k=0}^{Np-1}{\displaystyle {\sum }_{i-1}^{nu}\text{|}{w}_{\Delta ui}\Delta u_i\left(k\right){\text{|}}^2+{\displaystyle {\sum }_{k=0}^{Np-1}{\displaystyle {\sum }_{i=1}^{nu}\text{|}{w}_{ui}(u_i\left(k\right)}}}}-\\ u_{ref,i}\left(k\right){\text{|}}^2+{\displaystyle {\sum }_{k=0}^{Np-1}{\displaystyle {\sum }_{i=1}^{nu}\text{|}{w}_{y,i}\left(y_i\left(k\right)-y_{ref,i}\left(k\right)\right){\text{|}}^2,}}\end{array}$$

under the restrictions $$\begin{array}{l}{y}_{min,i}-\in v_y\le y_i\left(k\right)\le y_{max,i}+\in v_y\text{,}\\ \text{where i}=\text{1}\text{,}...{\text{, n}}_y\text{and k}=\text{1}\text{,}...\text{,}p\text{,}\end{array}$$

$$\begin{array}{l}{u}_{min.i}-\in v_u\le u_i\left(k\right)\le u_{max,i}+\in v_u,\\ \text{where i = 1}\text{,}...{\text{, n}}_u\text{and}k=\mathrm{1,}...,p-\mathrm{1,}\text{and}\end{array}$$

$$\begin{array}{l}\Delta u_{min,i}-\in v_{\mathrm{\Delta }\text{u}}\le \mathrm{\Delta }{\text{u}}_i\left(k\right)\le \mathrm{\Delta }{\text{u}}_{max,i}+\in v_{\mathrm{\Delta }\text{u}},\\ \text{where i}=\text{1}\text{,}...{\text{, n}}_u\text{and k}=\mathrm{1,}...,p-\mathrm{1,}\end{array}$$

where, as described above, $$y\left(k\right)=\mathrm{C.}x\left(k\right),$$

while is fulfilled $$x\left(k\right)=\text{Ax}\left(k-1\right)+\text{Bu}\left(\text{k}-1\right).$$

w _Δu , w _u and w _y are predetermined weight _values that are positive. v _Δu , v _u, and v _y are predetermined soft constraint _values that are greater than or equal to zero. The predetermined constraint values can be set to zero, for example, in order to impose hard constraints on the respective parameter. Values with the subscript min and max designate upper and lower limits for the respective parameters.

unter den Beschränkungen $$\text{Cx}\le \text{d},$$

wobei $$x\in {ℝ}^n,$$

$$Q\in {ℝ}^{n\times n},$$

$$C\in {ℝ}^{m\times n},$$

und $$d\in {ℝ}^m.$$

The above can be reformulated as a quadratic programming problem (QP problem) as, minimize: $$\frac{1}{2}{x}^{T}Qx-H^{T}x,$$

under the restrictions $$\text{Cx}\le \text{d},$$

in which $$x\in {ℝ}^n,$$

$$Q\in {ℝ}^{n\times n},$$

$$\mathrm{C.}\in {ℝ}^{m\times n},$$

and $$d\in {ℝ}^m.$$

Using the superscript T means applying a transpose.

1. (i) (x*, λ*) erfüllt $$Qx*-h-C^T\lambda *=\mathrm{0,}$$
   
2. (ii) Cx* ≤ d,λ* ≥ 0 und
3. (iii) λ*^T (d - Cx*) = 0.

x * ∈ ℝ ⁿ is the unique solution of the QP problem if and only if there is λ * ∈ ℝ ^m such that:

1. (i) (x *, λ *) fulfilled $$Qx*-H-{\mathrm{C.}}^T\lambda *=\mathrm{0,}$$
   
2. (ii) Cx * ≤ d, λ * ≥ 0 and
3. (iii) λ * ^T (d - Cx *) = 0.

Above, (ii) includes primal and dual constraint satisfaction, and (iii) includes complementarity. x can be referred to as a primal variable. λ can be referred to as a Lagrange multiplier or a dual variable. For QP problems that are constrained, an optimal solution includes an optimal pair of primal and dual variables.

A new variable y can be introduced, where $$y=d-\mathrm{C.}x.$$

in Termen von λ* und y* ausgedrückt, ergibt

1. (i) λ* ≥ 0, Cx* ≤ d ⇔ λ* ≥ 0, y* ≥ 0 und
2. (ii) λ*^T(d - Cx*⁾⁼⁰ ≥ 0 ⇔ λ*^Ty* = 0.

Accordingly, y * = d - Cx *. the equation $$Qx*-H-{\mathrm{C.}}^T\lambda *=0$$

expressed in terms of λ * and y *, gives

1. (i) λ * ≥ 0, Cx * ≤ d ⇔ λ * ≥ 0, y * ≥ 0 and
2. (ii) λ * ^T (d - Cx * ^{) = 0} ≥ 0 ⇔ λ * ^T y * = 0.

Solved for x *, we have $$x*=Q^{-1}\left(H-{\mathrm{C.}}^T\lambda *\right).$$

und $$y*=d-C{Q}^{-1}\left(h-C^T\lambda *\right)=d-C{Q}^{-1}h+C{Q}^{-1}{C}^T\lambda *.$$

Therefore, $$y*=d-\mathrm{C.}x*=\text{d}-\text{C.}\left[Q^{-1}\left(H-{\mathrm{C.}}^T\lambda *\right)\right],$$

and $$y*=d-\mathrm{C.}{Q}^{-1}\left(H-{\mathrm{C.}}^T\lambda *\right)=d-\mathrm{C.}{Q}^{-1}H+\mathrm{C.}{Q}^{-1}{\mathrm{C.}}^T\lambda *.$$

und $$\tilde{Q}:=C{Q}^{-1}{C}^T,$$

haben wir $$y*=\tilde{d}-\tilde{Q}\lambda *.$$

Be it $$\tilde{\text{d}}\text{: = d}-{\text{CQ}}^{-1}H$$

and $$\tilde{Q}:=\mathrm{C.}{Q}^{-1}{\mathrm{C.}}^T,$$

do we have $$y*=\tilde{d}-\tilde{Q}\lambda *.$$

1. (i) (x*, λ*) erfüllt $$\tilde{\text{d}}=\left(\text{I}-\tilde{Q}\right)\left({}_{\lambda *}^{y*}\right),$$
   
2. (ii) λ* ≥ 0 y* ≥ 0 und
3. (iii) λ*^Ty* = 0.

I ist eine Identitätsmatrix.Accordingly,

1. (i) (x *, λ *) fulfilled $$\tilde{\text{d}}=\left(\text{I.}-\tilde{Q}\right)\left({}_{\lambda *}^{y*}\right),$$
   
2. (ii) λ * ≥ 0 y * ≥ 0 and
3. (iii) λ * ^T y * = 0.

I is an identity matrix.

x * can therefore be determined using the following equation $$x*=Q^{-1}\left(H-{\mathrm{C.}}^T\lambda *\right).$$

A solver that solves for the optimal pair (x *, λ *) that satisfies conditions (i) - (iii) can be called a dual solver. The optimization module 320 includes a dual solver and solves for the optimal pair (x *, λ *) as described above.

x * includes optimal values that change the target values 266-270 from the previous control loop (e.g. k-1). The optimization module 320 fits the target values 266-270 from the previous control loop, each based on the values of x *, to the target values 266-270 for the current control loop to control the respective actuators. The optimization module 320 the target values 266-270 with the values x * sum to get the target values 266-270 for the current control loop.

und $${\text{u}}^{T}w=\mathrm{0,}\text{ u}\ge \mathrm{0,}\text{ und w}\ge \mathrm{0,}$$

wobei w = y*, u = λ*, A = Q̃ und q = d.The above could be rewritten as $$\text{w}-\text{Au}=\text{q},$$

and $${\text{u}}^{T}w=\mathrm{0,}\text{u}\ge \mathrm{0,}\text{and w}\ge \mathrm{0,}$$

where w = y *, u = λ *, A = Q̃ and q = d.

The problem of finding (w, u) that satisfy the above can be referred to as a Linear Complementarity Problem (LCP) and is handled by the optimization module 320 solved. More specifically, this form can be used by a Dantzig QP solver. The symmetric matrix A and the vector q include predetermined data. A can be called a tableau. The size of the tableau affects the number of calculations that are necessary to achieve the target values 266-270 to create.

m is the number of constraints other than the lower bound constraints on x. Let nL be the number of components of x that have lower bounds. nL is less than or equal to the number of target values nu. The total number of constraints that the QP solver takes into account in determining the optimal values is: $$m=\overline{m}+n_L.$$

wobei die Gesamtzahl von Reihen der C Matrix gleich der Gesamtzahl von Beschränkungen (m) ist. A ist daher eine (m + n_L) × (m, + n_L) Matrix (d.h., eine mxm-Matrix).As stated above, $$A=\tilde{Q}={\text{CQ}}^{-1}{\mathrm{C.}}^T,$$

where the total number of rows of the C matrix is equal to the total number of constraints (m). A is therefore a ( m + n _L ) × ( m , + n _L ) matrix (ie, an mxm matrix).

Other types of QP solver, such as a primal QP solver, assume that all components of x have lower bounds. Therefore, components of x that have no lower bounds will have artificial lower bounds, such as large negative numbers. The A matrix in such implementations will therefore always be a ( m + n _u ) × ( m + n _u ) be a matrix.

Since n _{L is} less than or equal to nu, the use of the A matrix of size ( m + n _L ) × ( m + n _L ) by the optimization module 320 to get the target values 266-270 to be determined, therefore at least computationally as efficient as the use of the A matrix with the size ( m + n _u ) × ( m + n _u ) if all components of x have lower bounds (and therefore nL = nu). Using the A matrix of size (m + n _L ) × ( m + n _L ) by the optimization module 320 to get the target values 266-270 is computationally more efficient than using the A matrix with the size ( m + n _u ) × ( m + n _u ) if one or more of the components of x have no lower bounds.

Now referring to 4th A flowchart depicting an exemplary method for estimating operating parameters and controlling the throttle valve is shown 112 , the intake cam phaser 148 , the exhaust cam phaser 150 , the boost pressure control valve 162 (and thus the turbocharger) and the EGR valve 170 using MPC (Model Predictive Control) shows. The control can be at 404 begin where the torque request module 224 based on the adjusted predicted torque requirements and the adjusted immediate torque requirements 263 and 264 the air torque requirement 265 certainly.

At 408 can do the torque conversion module 304 the air torque requirement 265 for use by the MPC module 312 into the base air torque request 308 or convert to any other suitable type of torque. At 412 determines the state estimator module 316 the states of the engine 102 for the current control loop as described above.

At 416 determines the optimization module 320 the optimal pair (x *, λ *) for determining the target values 266-270 as described above. The optimization module 320 determined at 420 the target values in each case 266-270 for the current control loop based on the target values 266-270 for the last control loop and the values of x *. The optimization module only determines by way of example 320 the target values 266-270 by adding the values x * with the target values 266-270 for the last control loop.

At 428 sets the first implementation module 272 the target wastegate opening area 266 in the target duty cycle 274 to that of the boost pressure control valve 162 is to be created, sets the second conversion module 276 the target throttle orifice area 267 in the target duty cycle 278 to that of the throttle valve 112 should be created. In addition, the third implementation module continues 280 at 428 the target EGR opening area 268 in the target duty cycle 282 around that to the EGR valve 170 should be created. In addition, the fourth conversion module can set the target intake cam phaser angle and the target exhaust cam phaser angle 269 and 270 convert each into the target intake cycle rate and the target exhaust cycle rate that is sent to the intake cam phaser or to the exhaust cam phaser 148 or. 150 should be created.

At 432 controls the throttle actuator module 116 the throttle valve 112 to get the target throttle area 267 and controls the phaser actuator module 158 the intake cam phaser and the exhaust cam phaser 148 and 150 to set the target intake cam phaser angle and the target exhaust cam phaser angle, respectively 269 or. 270 to reach. For example, the throttle actuator module 116 a signal with the target duty cycle 278 to the throttle valve 112 apply to the target throttle orifice area 267 to reach. The EGR actuator module also controls 172 the EGR valve 170 at 432 to the target EGR opening area 268 and controls the boost pressure actuator module 164 the boost pressure control valve 162 to get the target wastegate opening area 266 to reach. For example, the EGR actuator module 172 a signal with the target duty cycle 282 to the EGR valve 170 apply to the target EGR opening area 268 to reach, and can the boost pressure actuator module 164 a signal with the target duty cycle 274 to the boost pressure control valve 162 apply to the target wastegate opening area 266 to reach. Although 4th than after 432 shown ending may 4th represent a control loop and the control loops can be executed at a predetermined rate.

The foregoing description is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. The broad teachings of the disclosure can be implemented in a variety of forms. Thus, while this disclosure includes specific examples, it is not intended that the true scope of the disclosure be limited thereto as other changes will emerge from a study of the drawings, description, and the following claims. As used herein, the phrase at least one of A, B, and C is intended to mean a logical (A or B or C) using a non-exclusive logical OR. It is to be understood that one or more steps within a method can be performed in a different order (or simultaneously) without changing the principles of the present disclosure.

In this application, including in the following definitions, the term module can be replaced by the term circuit. The term module can refer to an application-specific integrated circuit (ASIC), a digital, analog or mixed analog / digital discrete circuit; to a digital, analog or mixed analog / digital integrated circuit; to a combinational logic circuit; on a freely programmable logical arrangement (FPGA), on a processor (shared, dedicated or group) that executes code, on memory (shared, dedicated or group) that stores code executed by a processor, on other suitable hardware components, that provide the functionality described, or relate to, be part of, or comprise a combination of some or all of the above, such as in a one-chip system.

The term code as used above can include software, firmware and / or microcode and can refer to programs, routines, functions, classes and / or objects. The term shared processor includes a single processor that executes some or all of the code of multiple modules. The term group processor includes a processor that executes some or all of the code from one or more modules along with additional processors. The term shared memory encompasses a single memory that stores some or all of the code from multiple modules. The term group memory encompasses a memory that stores some or all of the code from one or more modules along with additional memories. The term memory can be a subset of the term computer-readable medium. The term computer readable medium does not encompass transient electrical and electromagnetic signals propagating through a medium and thus can be viewed as concrete and non-transitory. Non-limiting examples of non-transitory specific computer readable medium include non-volatile memory, volatile memory, magnetic storage, and optical storage.

The devices and methods described in this application can be implemented in part or in full by one or more computer programs that are executed by one or more processors. The computer programs include processor-executable instructions stored on at least one non-transitory concrete computer-readable medium. The computer programs can also include and / or be based on stored data.

Claims (3)

An engine control method for a vehicle (102) comprising: Generating a first torque request (265) for a spark ignition engine (100) based on a driver input (404); Converting the first torque request (265) into a second torque request (308) (408); using a model predictive control (MPC) module (312), determining a set of target values (266-270) based on the second torque request (308), a model of the engine (102) and a matrix of dimensions (m + n) times (m + n), where n is an integer greater than zero that is equal to a number of lower bounds used in determining the set of target values (266-270), and m is an integer greater than zero that is equal to a number of constraints used in determining the set of target values (266-270) other than the lower limit constraints (416); and Controlling an opening (278) of a throttle valve (112) based on a first (267) of the target values (266-270) (428, 432); Controlling an opening (274) of a wastegate valve (162) of a turbocharger (160-1, 160-2) based on a second (266) of the target values (266-270) (428, 432); Controlling an opening (282) of an EGR valve (170) based on a third party (268) of the target values (266-270) (428, 432); and Controlling an intake valve phasing (269) of an intake cam phaser (148) and an exhaust valve phasing (270) of an exhaust cam phaser (150) based on a fourth (269) and a fifth (270) of the target values (266), respectively -270) (428, 432). Engine control method according to Claim 1 further comprising: determining reference values (356) for the respective target values (266-270); and determining the target values (266-270) further based on the reference values (356). Engine control method according to Claim 1 , where the constraints include constraints on target values (266-270) and constraints on controlled variables.

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