JP5428914B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a control device for a vehicle in which a supercharged internal combustion engine having intake pressure detecting means for detecting intake pressure of an intake system in which a throttle valve is disposed is mounted.

  As a control device for a vehicle in which an internal combustion engine with a supercharger is mounted, in order to suppress a so-called turbo lag (supercharging delay), a virtual intake pressure upstream of the throttle valve (hereinafter referred to as a virtual throttle upstream pressure) is provided. Using a virtual internal combustion engine model, the target intake air amount is calculated according to the accelerator opening, and the required throttle according to the intake pressure upstream of the actual throttle valve so as to realize the target intake air amount A device that calculates an opening and controls a throttle valve based on a required throttle opening is known (for example, see Patent Document 1).

JP 2007-56697 A

  By the way, in a vehicle including a supercharged internal combustion engine having a throttle valve (electronically controlled throttle valve) controlled independently of the accelerator operation, a command from an ECU other than the engine such as an ECU (Electronic Control Unit) of a transmission As a result, the throttle opening may be decreased, and the actual intake pressure downstream of the throttle valve (hereinafter referred to as actual intake manifold pressure) may decrease. For this reason, when setting the virtual throttle upstream pressure based on the actual intake manifold pressure and setting the operation parameters such as the driver request torque, it is necessary to consider the situation.

  In view of the above circumstances, the present invention suitably sets the virtual throttle upstream pressure and suitably sets the operating parameters such as the driver request torque regardless of the operating state of the internal combustion engine such as the accelerator opening and the throttle opening. It is an object of the present invention to provide a vehicle control device that can be used.

  In order to achieve the above object, a vehicle control device is a vehicle control device in which an internal combustion engine with a supercharger having intake pressure detection means for detecting intake pressure of an intake system in which a throttle valve is arranged is mounted. A correlation value that correlates with the degree of increase of the supercharging pressure by the supercharger is set according to the operating condition detecting means for detecting the operating condition of the internal combustion engine and the operating condition detected by the operating condition detecting means. A correlation value setting means; an intake pressure correction value setting means for setting a correction value obtained by correcting an intake pressure detection value by the intake pressure detection means based on a correlation value by the correlation value setting means; Virtual throttle upstream pressure setting means for setting a virtual throttle upstream pressure, which is a virtual value of the intake pressure upstream of the throttle valve, based on the correction value set by the correction value setting means; and the virtual Throttle set by the upstream pressure setting means based on said virtual upstream intake air pressure, and a driving parameter setting means for setting the operating parameters of the internal combustion engine.

In the vehicle control apparatus, the intake pressure correction value setting means obtains a correction value for the current predetermined period based on an addition value obtained by adding the correlation value to the correction value obtained for the previous predetermined period. Also good.
In the vehicle control apparatus, the intake pressure correction value setting means is configured to calculate a larger one of a detected value of the intake pressure detected by the intake pressure detecting means and the added value during the predetermined period of time. You may set as a correction value in this predetermined period.

The vehicle control apparatus may include an atmospheric pressure detection unit that detects an atmospheric pressure, and the intake pressure correction value setting unit includes a detected value of the atmospheric pressure detected by the atmospheric pressure detection unit, and the current pressure detection value. The largest value of the detected value of the intake pressure detected by the intake pressure detecting means during the predetermined period and the added value may be set as the correction value for the predetermined period.
In the vehicle control apparatus, the throttle valve may be capable of controlling an opening degree independently of an accelerator of the vehicle, and the driving state detecting means detects an accelerator opening degree of detecting the accelerator opening degree. Detection means and valve opening / closing state detection means for detecting the opening / closing state of the throttle valve, the correlation value setting means is different from the accelerator opening detected by the accelerator opening detection means, When the valve closed state is detected by the valve open / closed state detecting means, the correlation value may be integrated every predetermined period.

In the vehicle control apparatus, the correlation value is a value obtained by adding the opening of the accelerator of the vehicle to the rotation speed of the internal combustion engine and the opening of the throttle valve during idle operation of the internal combustion engine. It may be set based on the required throttle valve opening.
In the vehicle control apparatus, the virtual throttle upstream pressure setting means includes a correction value set by the intake pressure correction value setting means and a virtual intake pressure preset according to the accelerator opening of the vehicle. The smaller one of the virtual intake pressures may be set as the virtual throttle upstream pressure.

  According to the vehicle control apparatus, the virtual throttle upstream pressure is suitably set and the operation parameters such as the driver request torque are suitably set regardless of the operation state of the internal combustion engine such as the accelerator opening and the throttle opening. it can.

It is a schematic block diagram of the internal combustion engine with a supercharger. It is a functional block diagram which shows the structure of engine ECU. It is a map which shows correlation with a steady intake manifold pressure, throttle opening, and an engine speed. It is a flowchart for demonstrating the setting method of driver request torque Trd. (A) to (G) are timing charts showing changes in the accelerator opening Acc, the throttle opening θtv, the virtual throttle upstream pressure Ptv-v, and the like.

Embodiments of the present invention will be described below.
FIG. 1 is a schematic configuration diagram of an internal combustion engine with a supercharger to which a control device according to an embodiment of the present invention is applied. As shown in this figure, an engine 1 as a supercharger-equipped internal combustion engine includes a turbocharger that is driven by exhaust gas energy as a supercharger 10.
The engine 1 includes a cylinder block 20, a cylinder head 30 fixed on the cylinder block 20, an intake system 40 for supplying a mixture of fuel and air to the cylinder block 20, a cylinder And an exhaust system 50 for releasing the exhaust gas from the block unit 20 to the outside.

  The cylinder block unit 20 includes a cylinder 21, a piston 22, a connecting rod 23, and a crankshaft 24. The piston 22 reciprocates in the cylinder 21, and the reciprocating motion of the piston 22 is transmitted to the crankshaft 24 through the connecting rod 23, whereby the crankshaft 24 rotates. The cylinder 21, the head of the piston 22, and the cylinder head portion 30 form a combustion chamber (cylinder) 25.

  The cylinder head portion 30 has an intake port 31 communicating with the combustion chamber 25, an intake valve 32 that opens and closes the intake port 31, an intake cam shaft that drives the intake valve 32, and continuously changes the phase angle of the intake cam shaft. The variable intake timing device 33, the actuator 33A of the variable intake timing device 33, the exhaust port 34 communicating with the combustion chamber 25, the exhaust valve 35 that opens and closes the exhaust port 34, the exhaust camshaft 36 that drives the exhaust valve 35, and the spark plug 37 And an igniter 38 having an ignition coil for generating a high voltage to be applied to the spark plug 37 and an injector 39 for injecting fuel into the intake port 31.

  The intake system 40 includes an intake manifold 41 that communicates with the intake port 31, a surge tank 42 that communicates with the intake manifold 41, and one end connected to the surge tank 42 to form an intake passage together with the intake port 31, the intake manifold 41, and the surge tank 42. Intake duct 43, air filter 44, compressor 10A of supercharger 10, intercooler 45, throttle valve 46, and air filter 44 disposed in order from the other end of intake duct 43 to the downstream (surge tank 42) A throttle valve actuator 46A is provided.

  The throttle valve 46 is an electronically controlled throttle valve, and is rotatably supported by the intake duct 43. The throttle valve 46 is driven by a throttle valve actuator 46A to adjust the opening degree. As a result, the throttle valve 46 can change the passage sectional area of the intake duct 43. The opening degree of the throttle valve 46 (throttle opening degree) is defined by an angle rotated from the position of the throttle valve 46 in a state where the passage sectional area is minimized.

  A throttle valve actuator 46A formed of a DC motor includes an engine ECU 70, which will be described later, and an ECU 80 of a unit other than the engine (AT (Automatic Transmission), CVT (Continuously Variable Transmission), DCT (Dual Clutch Transmission), ESC (Electronic Stability Control), etc.). The throttle valve 46 is driven according to the drive signal to be transmitted. In the following, DCT is taken as an example of a unit other than the engine.

The exhaust system 50 includes an exhaust pipe 51 having an exhaust manifold that communicates with the exhaust port 34 and forms an exhaust passage together with the exhaust port 34, the turbine 10B of the supercharger 10 disposed in the exhaust pipe 51, and the downstream of the turbine 10B. The exhaust pipe 51 is provided with a catalyst 52.
With such an arrangement, the turbine 10B of the supercharger 10 is rotated by the energy of the exhaust gas. Further, the turbine 10B is connected to the compressor 10A of the intake system 40 via a shaft. Thus, the compressor 10A of the intake system 40 rotates integrally with the turbine 10B to compress the air in the intake passage. That is, the supercharger 10 supercharges air to the engine 1 using the energy of the exhaust gas.

On the other hand, this system includes an intake pressure sensor 61, a throttle valve sensor 62, an accelerator opening sensor 63, a cam position sensor 64, a crank position sensor 65, an atmospheric pressure sensor 66, an engine ECU 70, and a DCT ECU 80.
The intake pressure sensor 61 detects the pressure of intake air downstream of the throttle valve 46, that is, the actual pressure (hereinafter referred to as actual intake manifold pressure) Pim in the surge tank 42, and outputs a detection signal to the engine ECU 70. The throttle valve sensor 62 detects the opening / closing state of the throttle valve 46 such as the opening (throttle opening) θtv of the throttle valve 46 and outputs a detection signal to the engine ECU 70. Here, the throttle valve sensor 62 is open or closed as an open / closed state of the throttle valve 46, whether the throttle valve sensor 62 is moving toward the open side or moving toward the closed side, what is the speed of the movement, Is detected.

The accelerator opening sensor 63 detects an operation amount (accelerator opening) Acc of the accelerator pedal 67 operated by the driver and outputs a detection signal to the engine ECU 70.
The cam position sensor 64 generates a signal having one pulse every time the intake camshaft rotates 90 ° (that is, every time the crankshaft 24 rotates 180 °). Crank position sensor 65 detects engine speed Ne and outputs a detection signal to engine ECU 70. The atmospheric pressure sensor 66 detects the atmospheric pressure Pair and outputs a detection signal to the engine ECU 70.

  The engine ECU 70 performs predetermined arithmetic processing by a built-in microcomputer while inputting signals from the above-described various sensors, the throttle opening θtv by the throttle valve 46, the fuel injection amount and injection timing by the injector 39, The ignition timing by the spark plug 37 is controlled. In the control of the throttle valve 46, the throttle valve actuator is set so as to obtain the required throttle opening θtv ′ according to the driver required torque Trd set from the accelerator opening Acc, the engine speed Ne, etc. 46A is driven to control the throttle opening degree θtv. Here, the required throttle opening degree θtv ′ is a value obtained by adding the accelerator opening degree Acc and the throttle opening degree θtv during idling.

Further, the engine ECU 70 and the ECU 80 of the DCT perform cooperative control between the engine 1 and the DCT. In this cooperative control, the engine ECU 70 transmits the driver request torque Trd to the DCT ECU 80, and the DCT ECU 80 controls the DCT in accordance with the received driver request torque Trd.
Further, the DCT ECU 80 transmits the DCT-side required torque Tdct to the engine ECU 70, and the engine ECU 70 sets the required throttle opening degree θtv ′ in accordance with the received required torque Tdct and obtains the throttle. The valve actuator 46A is driven to control the throttle opening θtv. Here, when the driver request torque Trd or the like and the DCT side request torque Tdct compete with each other, the engine ECU 70 sets the required throttle opening θtv ′ by giving priority to the latter, and controls the throttle opening θtv. To do.

FIG. 2 is a functional block diagram showing a configuration of engine ECU 70. As shown in this figure, the engine ECU 70 includes a correlation value setting unit 76, a corrected intake manifold pressure setting unit 71, a virtual throttle upstream pressure setting unit 72, a driver request torque setting unit 73, a cooperative control unit 74, a throttle And a control unit (ETV control unit) 75.
The correlation value setting unit 76 includes a map M1 indicating the relationship between the supercharging pressure Psc and the engine speed Ne in a situation where the throttle opening θtv increases following the increase in the accelerator opening Acc, and the excess in the situation. It has a map M2 showing the relationship between the supply pressure Psc and the required throttle opening degree θtv ′. The correlation value setting unit 76 determines the degree of increase in the supercharging pressure Psc by the supercharger 10 based on the parameters representing the operating state of the engine 1 such as the throttle opening θtv and the engine speed Ne and the maps M1 and M2. A correlation value ΔPsc to be correlated is set. Here, the correlation value setting unit 76, when the accelerator opening Acc is increased, but the increase of the throttle opening θtv is restricted by the cooperative control unit 74 (or the throttle valve 46 is closed). Case), that is, when a predetermined addition condition is satisfied, the correlation value ΔPsc is integrated per unit time. The correlation value ΔPsc is an increase amount ΔPsc of the supercharging pressure per unit time. When the increase in the throttle opening θtv is restricted (or when the throttle valve 46 is closed), the unit time Increase by a predetermined amount per hit.

  The corrected intake manifold pressure setting unit 71 corrects the actual intake manifold pressure Pim by integrating the increase amount ΔPsc of the boost pressure per unit time set by the correlation value setting unit 76 per unit time ( Hereinafter, Pim-v is calculated. That is, the corrected intake manifold pressure setting unit 71 calculates the corrected intake manifold pressure Pim-v as an addition value obtained by adding the correlation value to the correction value obtained in the previous predetermined period.

  Then, the corrected intake manifold pressure setting unit 71 compares the calculated corrected intake manifold pressure Pim-v with the actual intake manifold pressure Pim detected by the intake pressure sensor 61 and the atmospheric pressure Pair detected by the atmospheric pressure sensor 66. The maximum value among them is set to the corrected intake manifold pressure Pim-v. Note that it is not essential to set the atmospheric pressure Pair as a comparison target. The larger one of the corrected intake manifold pressure Pim-v and the actual intake manifold pressure Pim may be set as the corrected intake manifold pressure Pim-v. Good.

  The virtual throttle upstream pressure setting unit 72 assumes that when the accelerator opening Acc increases, the throttle opening θtv increases following the increase, and the actual intake manifold pressure Pim increases without being affected by the delay of the boost pressure increase. And a map M3 (see FIG. 3) showing the correlation between the intake manifold pressure (second virtual throttle downstream pressure) (hereinafter referred to as steady intake manifold pressure) Pim-s, the throttle opening θtv, and the engine speed Ne. ing.

  The virtual throttle upstream pressure setting unit 72 is a correction set by the correction intake manifold pressure setting unit 71 when the cooperative control unit 74 receives a torque limitation request from the ECU 80 of the DCT and limits the increase in the throttle opening θtv. The intake manifold pressure Pim-v is compared with the steady intake manifold pressure Pim-s read from the map M3, and the smaller one of these values is set as the virtual throttle upstream pressure Ptv-v.

  The driver request torque setting unit 73 has a map M4 indicating the relationship between the accelerator opening degree Acc, the engine speed Ne, and the like and the driver request torque Trd. The driver request torque Trd obtained from the map M4 is used as a virtual throttle. Correction is performed using a ratio (Ptv-v / Pim-s) between the virtual throttle upstream pressure Ptv-v set by the upstream pressure setting unit 72 and the steady intake manifold pressure Pim-s read from the map M3. That is, the driver request torque setting unit 73 sets the driver request torque Trd as an operation parameter based on the virtual throttle upstream pressure Ptv-v and the steady intake manifold pressure Pim-s.

The cooperative control unit 74 transmits the driver request torque Trd set by the driver request torque setting unit 73 to the ETV control unit 75 and the ECU 80 of the DCT. Further, the cooperative control unit 74 transmits the required torque Tdct transmitted from the DCT ECU 80 to the ETV control unit 75.
The ETV control unit 75 sets the required throttle opening degree θtv ′ based on the driver required torque Trd or the DCT side required torque Tdct, and controls the throttle opening degree θtv so that this is achieved.

FIG. 4 is a flowchart for explaining a method for setting the driver request torque Trd. FIGS. 5A to 5G are timing charts showing changes in accelerator opening Acc, throttle opening θtv, virtual throttle upstream pressure Ptv-v, and the like.
As shown in the flowchart of FIG. 4, first, in step 100, the correlation value setting unit 76 sets predetermined acceleration conditions such that the accelerator opening Acc is equal to or greater than a certain value and the engine speed Ne is equal to or greater than a certain value. It is determined whether or not it is established. If the determination is affirmative, the process proceeds to step 102. If the determination is negative, step 100 is repeatedly executed. In step 102, the correlation value setting unit 76 determines whether or not a predetermined addition condition is satisfied, that is, as shown in the timing charts of FIGS. When the increase in the degree θtv is limited, it is determined whether or not the accelerator opening Acc increases but the throttle opening θtv does not increase. If the determination is affirmative, the routine proceeds to step 104. If the determination is negative, the routine proceeds to step 106.

  In step 104, the correlation value setting unit 76 calculates the increase amount ΔPsc per unit time of the supercharging pressure from the maps M1 and M2 for each unit time. Then, the corrected intake manifold pressure setting unit 71 calculates the increase amount ΔPsc per unit time of the boost pressure calculated by the correlation value setting unit 76 per unit time as the corrected intake manifold pressure Pim-v (initial value) set previously. Is added to the atmospheric pressure Pair (see the timing chart of FIG. 5E). Next, in step 106, the corrected intake manifold pressure setting unit 71 adds the increase amount ΔPsc of the boost pressure to the previously set corrected intake manifold pressure Pim-v, and the actual intake manifold pressure detected by the intake pressure sensor 61. Pim and the atmospheric pressure Pair detected by the atmospheric pressure sensor 66 are compared, and the maximum value among them is set as the corrected intake manifold pressure Pim-v.

As shown in the timing chart of FIG. 5 (F), the corrected intake manifold pressure Pim-v becomes the atmospheric pressure Pair until time t2, and after time t2, the corrected intake manifold pressure Pim-v exceeds the previously set corrected intake manifold pressure Pim-v. A value obtained by adding the increase amount ΔPsc of the supply pressure.
Next, in step 108, the virtual throttle upstream pressure setting unit 72 reads the steady intake manifold pressure Pim-s from the map M <b> 3, the read steady intake manifold pressure Pim-s, and the corrected intake manifold pressure setting unit 71. The pressure Pim-v is compared, and the smaller one of these values is set as the virtual throttle upstream pressure Ptv-v.

As shown in the timing chart of FIG. 5G, the virtual throttle upstream pressure Ptv-v becomes the steady intake manifold pressure Pim-s until the time t1, and becomes the atmospheric pressure Pair between the times t1 and t2. During the time t2 to t3, the corrected intake manifold pressure Pim-v is obtained, and after the time t3, the steady intake manifold pressure Pim-s is obtained.
Next, in step 110, the driver request torque setting unit 73 obtains the driver request torque Trd from the map M4 indicating the relationship between the accelerator opening Acc, the engine speed Ne, etc. and the driver request torque Trd, and the obtained driver request torque. Trd is corrected using a ratio (Ptv-v / Pim-s) between the virtual throttle upstream pressure Ptv-v set by the virtual throttle upstream pressure setting unit 72 and the steady intake manifold pressure Pim-s read from the map M3. To do. Thus, the processing routine is finished.

  That is, in the present embodiment, as shown in the timing charts of FIGS. 5A and 5B, the throttle opening degree θtv is set despite the accelerator opening degree Acc being increased by the driver depressing the accelerator pedal 67. Is not increased (or the throttle valve 46 is closed), the throttle upstream pressure when the throttle opening θtv increases following the increase in the accelerator opening Acc is set in a simulated manner. Here, the throttle upstream pressure when the throttle valve 46 is open increases as the boost pressure increases. For this reason, when the accelerator opening Acc increases but the throttle opening θtv does not increase, by adding an amount corresponding to the increase amount of the boost pressure to the throttle upstream pressure every unit time, the accelerator opening Acc The throttle upstream pressure (virtual throttle upstream pressure) Ptv-v when the throttle opening θtv increases following the increase can be simulated.

Then, the ratio (Ptv-v / Pim-s) between the virtual throttle upstream pressure Ptv-v and the actual intake manifold pressure Pim and the intake manifold pressure (steady intake manifold pressure) Pim-s estimated from the current accelerator opening Acc. Using this, the driver request torque Trd is corrected.
Thus, even if the throttle valve 46 is closed due to a request from another ECU (such as the ECU 80 of the DCT) when the driver depresses the accelerator pedal 67, an appropriate throttle upstream pressure Ptv-v can be simulated, and the turbo lag is reduced. An appropriate driver request torque Trd considered can be calculated, and therefore, the driver request torque Trd suitable for the driver's request (accelerator opening Acc) can be transmitted to another ECU.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Engine 10 Supercharger 10A Compressor 10B Turbine 20 Cylinder block part 21 Cylinder 22 Piston 23 Connecting rod 24 Crankshaft 25 Combustion chamber 30 Cylinder head part 31 Intake port 32 Intake valve 33 Variable intake timing device 33A Actuator 34 Exhaust port 35 Exhaust valve 36 Exhaust camshaft 37 Spark plug 38 Igniter 39 Injector 40 Intake system 41 Intake manifold 42 Surge tank 43 Intake duct 43
44 Air filter 44
45 Intercooler 46 Throttle valve 46A Throttle valve actuator 50 Exhaust system 51 Exhaust pipe 52 Catalyst 61 Intake pressure sensor (intake pressure detection means)
62 Throttle valve sensor (operating state detecting means, valve open / closed state detecting means)
63 Accelerator opening sensor (operating state detecting means, accelerator opening detecting means)
64 Cam position sensor 65 Crank position sensor (Operating state detection means)
66 Atmospheric pressure sensor (atmospheric pressure detection means)
70 Engine ECU
71 Correction intake manifold pressure setting section (intake pressure correction value setting means)
72 Virtual throttle upstream pressure setting section (virtual throttle upstream pressure setting means)
73 Driver required torque setting section (operating parameter setting means)
74 Cooperation control unit 75 Throttle control unit 76 Correlation value setting unit 80 ECU of DCT

Claims (7)

A control device for a vehicle on which an internal combustion engine with a supercharger having an intake pressure detection means for detecting an intake pressure of an intake system in which a throttle valve is disposed is mounted,
An operating state detecting means for detecting an operating state of the internal combustion engine;
Correlation value setting means for setting a correlation value that correlates with the degree of increase in supercharging pressure by the supercharger, according to the operating condition detected by the operating condition detecting means;
An intake pressure correction value setting means for setting a correction value obtained by correcting the detected value of the intake pressure by the intake pressure detection means based on the correlation value by the correlation value setting means for each predetermined period;
Virtual throttle upstream pressure setting means for setting a virtual throttle upstream pressure, which is a virtual value of the intake pressure upstream of the throttle valve, based on the correction value set by the intake pressure correction value setting means;
Operation parameter setting means for setting an operation parameter of the internal combustion engine based on the virtual throttle upstream pressure set by the virtual throttle upstream pressure setting means;
A vehicle control apparatus comprising:   2. The vehicle according to claim 1, wherein the intake pressure correction value setting unit obtains a correction value for the current predetermined period based on an addition value obtained by adding the correlation value to the correction value obtained for the previous predetermined period. Control device.   The intake pressure correction value setting means corrects the larger of the detected value of the intake pressure detected by the intake pressure detection means and the added value in the predetermined period of time in the predetermined period of time. The vehicle control device according to claim 2, which is set as a value. Equipped with atmospheric pressure detection means for detecting atmospheric pressure,
The intake pressure correction value setting means includes the detected value of the atmospheric pressure detected by the atmospheric pressure detecting means, the detected value of the intake pressure detected by the intake pressure detecting means during the predetermined period, and the addition The vehicle control device according to claim 3, wherein the largest value among the values is set as a correction value in the current predetermined period. The throttle valve is capable of controlling the opening degree independently of the accelerator of the vehicle,
The operating state detecting means is
An accelerator opening detecting means for detecting the opening of the accelerator;
Valve opening / closing state detecting means for detecting the opening / closing state of the throttle valve,
Unlike the accelerator opening detected by the accelerator opening detecting means, the correlation value setting means integrates the correlation values every predetermined period when the valve open / closed state detecting means is detected. The vehicle control device according to any one of claims 1 to 4. The correlation value is
The rotational speed of the internal combustion engine;
A required throttle valve opening that is a value obtained by adding the opening of the throttle of the vehicle to the opening of the throttle valve during idle operation of the internal combustion engine;
The vehicle control device according to any one of claims 1 to 5, wherein the vehicle control device is set based on the following.   The virtual throttle upstream pressure setting means includes a correction value set by the intake pressure correction value setting means and a virtual intake pressure that is a virtual intake pressure preset according to the accelerator opening of the vehicle. The vehicle control device according to any one of claims 1 to 6, wherein the smaller one is set to the virtual throttle upstream pressure.

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