DE102009043205B4 - Method for selecting a transmission gear and for controlling a gear having gear and control system for a transmission - Google Patents

Abstract

A method of selecting a gear in a transmission (16) of a motor vehicle (10), comprising:
Determining a power request signal (82) in response to a pedal position and a vehicle speed (78);
Determining an engine speed (104, 162) of each gear in dependence on the vehicle speed (78) and the power request signal (82);
Determining an engine torque (106, 168) of each gear in dependence on the vehicle speed (78) and the power request signal (82);
Determining a transmission component speed (108, 122) of each gear in dependence on the vehicle speed (78) and the power request signal (82);
Determining cost (214) for each gear using a cost function and in dependence on engine speed (104, 162) and engine torque (106, 168);
Determining a penalty (218) for each gear based on drive behavior limitations and in response to the power request signal (82) and the engine speed (104, 162);
Merging the respective costs (214) for each gear with the respective trigger (218) for each gear and thereby determining final costs (220) for each gear; such as
Comparing the final cost (220) for each gear and selecting a gear with the lowest final cost (220).

Description

FIELD OF THE INVENTION

The present invention relates to a method for selecting a gear in a transmission of a motor vehicle, a method for controlling a gear having a gear and a control system for a transmission.

STATE OF THE ART

In DE 10 2006 009 589 A1 A method for selecting a gear in a transmission of a motor vehicle is described, the method comprising: determining a power request signal; Determining an engine speed; Determining a motor torque; Determining a transmission component speed; and determining a gear selection for the transmission based on the power request signal, the engine speed, the engine torque, and the transmission component speed.

In DE 195 32 124 C2 A method of controlling a gear having a gear is described, the method comprising: determining a turbine speed for the gear; Determining an engine speed; Determining a motor torque; Determining costs for each course; Determining a minimum cost gear based on the costs determined for each gear; and controlling the transmission so that the minimum cost gear is selected.

BACKGROUND OF THE INVENTION

Internal combustion engines (IC engines) generate torque by burning an air / fuel mixture. The torque provides propulsive power to the wheels via a transmission and other powertrain components.

In 1 An automatic transmission uses shift maps to define the points for upshifting and downshifting of the transmission in the various gears. In 1 Figure 11 illustrates a typical shift map in which the solid lines represent upshift speed lines and the dashed lines show downshift speed lines. The upshift and downshift lines are based on throttle position and vehicle speed. Since the control is limited to only two variables, the control is limited. Certain conditions can not be taken into account when determining the switching operation.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide control of shifting operations in a transmission based on a more comprehensive evaluation of given conditions so as to improve drivability and fuel economy for the transmission and the associated vehicle.

This is achieved by a method according to claim 1, a method according to claim 7 or a control system according to claim 15. Further developments of the invention are defined in the respective dependent claims.

The present invention eliminates the limited controllability of shifts based only on the throttle and vehicle speed. Various other conditions in the shift decision may be considered to improve driveability and fuel economy for the transmission and associated vehicle.

Further fields of application of the present invention will become apparent from the following detailed description.

list of figures

• 1 ein Diagramm der Drosselklappenstellung gegenüber der Fahrzeuggeschwindigkeit ist, das Hochschaltvorgänge in durchgezogenen Linien und Herunterschaltvorgänge in gestrichelten Linien veranschaulicht;
• 2 eine schematische Darstellung eines beispielhaften Fahrzeugs ist, das auf der Grundlage des Generatordrehmoment-Schätzsystems gemäß der vorliegenden Erfindung betrieben wird;
• 3 ein Blockdiagramm des Steuermoduls von 2 ist, um die Gangwahl in Echtzeit zu bestimmen;
• 4 ein Blockdiagramm des Echtzeit-Wahlmoduls von 3 ist;
• 5 ein Blockdiagramm eines Turbinenraddrehzahl-Bestimmungsmoduls in dem Drehmoment- und Drehzahl-Rechner 102 von 4 ist;
• 6 ein Blockdiagramm eines Abschnitts des Drehmoment- und Drehzahlrechners von 4 ist;
• 7 ein Blockdiagramm des Moduls von 4 für die Wahl des optimalen Gangs ist;
• 8 ein Blockdiagramm einer ersten Ausführungsform eines Kostenbestimmungsmoduls ist;
• 9 ein Blockdiagramm einer zweiten Ausführungsform eines Kostenbestimmungsmoduls ist;
• 10 ein Blockdiagramm einer dritten Ausführungsform eines Kostenbestimmungsmoduls ist;
• 11 ein Blockdiagramm einer vierten Ausführungsform eines Kostenbestimmungsmoduls ist;
• 12 ein Blockdiagramm einer ersten Ausführungsform eines Abzug-Bestimmungsmoduls ist;
• 13 ein Blockdiagramm einer zweiten Ausführungsform des Abzug-Bestimmungsmoduls ist; und
• 14 ein Blockdiagramm einer dritten Ausführungsform eines Abzug-Bestimmungsmoduls ist.

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

• 1 Figure 12 is a plot of throttle position versus vehicle speed illustrating upshifts in solid lines and downshifts in dashed lines;
• 2 FIG. 12 is a schematic illustration of an exemplary vehicle operated based on the generator torque estimation system of the present invention; FIG.
• 3 a block diagram of the control module of 2 is to determine the gear selection in real time;
• 4 a block diagram of the real-time dialer of 3 is;
• 5 a block diagram of a turbine wheel speed determination module in the torque and speed calculator 102 from 4 is;
• 6 a block diagram of a portion of the torque and speed calculator of 4 is;
• 7 a block diagram of the module of 4 for choosing the optimal gear;
• 8th Fig. 10 is a block diagram of a first embodiment of a cost determination module;
• 9 Fig. 10 is a block diagram of a second embodiment of a cost determination module;
• 10 Fig. 10 is a block diagram of a third embodiment of a cost determination module;
• 11 Fig. 10 is a block diagram of a fourth embodiment of a cost determination module;
• 12 Fig. 10 is a block diagram of a first embodiment of a fume determination module;
• 13 Fig. 10 is a block diagram of a second embodiment of the trigger determination module; and
• 14 is a block diagram of a third embodiment of a deduction determination module.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description of the preferred embodiment is merely exemplary in nature. For the sake of clarity, the same reference numbers will be used in the drawings to identify similar elements. As used herein, the term module refers to an application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated or group) and memories that execute one or more software or firmware programs. a combinational logic circuit and / or other suitable components that provide the described functionality.

In 2 contains an exemplary vehicle 10 an engine 12 , a generator 14 and a gearbox 16 , The motor 12 generates drive torque to the generator 14 and the gearbox 16 drive. More specifically, the engine sucks 12 Air in an intake manifold 18 which distributes the air to a cylinder (not shown) where it is combined with fuel to form an air / fuel mixture. The air / fuel mixture is burned to drive a piston (not shown) in the cylinder, thereby producing a crankshaft 20 is driven to generate drive torque. The combustion process is initiated by a spark generated by a spark plug (not shown). The timing of the spark ignition relative to the position of the piston in the cylinder may be adjusted (ie, can lead or lag) to regulate exhaust temperature, engine torque, and manifold absolute pressure (MAP).

The motor 12 and the alternator 14 are via a belt system 22 coupled. The motor 12 and the generator 14 included pulleys 24 respectively. 26 that are coupled by a strap 28 to be turned around. The pulley 24 is non-rotatable with the crankshaft 20 of the motor 12 coupled. The motor 12 drives the generator 14 to generate power used by vehicle systems and / or an energy storage device (ESD). 30 recharge. The generator 14 exerts a variable load on the engine 12 (T _GEN ) generated by a voltage regulator (VR) 32 is regulated. When from the generator 14 more electrical energy is required, increases the VR 32 the T _GEN , thereby increasing the engine operating amount. If less electrical energy from the generator 14 is demanded, the VR lowers 32 the T _GEN , thereby lowering the motor work amount.

The gear 16 may include an automatic transmission and / or a semi-automatic transmission (AMT, automated, manual transmission). From the engine crankshaft 20 gets to the gearbox 16 to a coupling device 34 Transmitted drive torque. The coupling device 34 may include, but is not limited to, a friction clutch or a torque converter, depending on the type of transmission implemented. The gear 16 multiplies the drive torque over one of several gear ratios to one drive shaft 36 drive.

A control module 38 regulates the operation of the vehicle 10 by the generator torque estimation system of the present invention. The control module 38 controls engine airflow, fuel injection, spark, and alternator load to regulate engine torque output. One manifold absolute pressure sensor (MAP sensor) 40 Refers to the MAP in the intake manifold 18 and generates a MAP signal based thereon. An engine temperature sensor 42 responds to an engine temperature and generates an engine temperature signal based thereon. It is assumed that the engine temperature based on a coolant temperature and / or an oil temperature of the engine 12 can be determined. An ambient temperature sensor 44 responds to an ambient temperature and generates an ambient temperature signal based thereon. It is anticipated that engine temperature may be further determined based on ambient temperature. A speed sensor 46 Refers to the RPM of the engine 12 and generates a speed signal based thereon. An accelerator pedal 48 has a pedal position sensor 50 , which indicates a position of the accelerator pedal 48 responds. The pedal position sensor 50 generates a pedal position signal based thereon.

A vehicle speed sensor 60 can also use the control module 38 communicate. The vehicle speed sensor 60 generates a vehicle speed signal corresponding to the speed of the vehicle.

It also allows the control module 38 a memory 62 be assigned. The memory 62 can store various intermediate calculation values or other values such as constants used in the calculations. For example, wheel parameters, axle or driveline ratio, gear ratio efficiency, and engine fuel rate lookup tables may be stored in memory. The memory may be one of many different types of memory or combinations of memories, including volatile memory, non-volatile memory and a latch.

Regarding 3 will now be details in the control module 38 explained. A pedal input interpretation module 80 receives a pedal position signal 76 , which corresponds to the pedal position, from the pedal position sensor 50 and a vehicle speed signal 78 from the vehicle speed sensor 60 , in the 2 are shown. Based on the pedal position signal 76 and the vehicle speed signal 78 becomes a power request signal 82 generated. The power request signal 82 is applied to a motor torque command generator module 84 transmits a motor drive torque command based on the power request signal 86 generated to a torque-based engine control module 88 is transmitted. In response to the commanded drive torque, the motor is controlled to achieve the commanded power and commanded motor drive torque.

The engine torque command generator 84 generates a motor drive torque command by simply dividing the power demand by the current engine speed. The torque-based engine control system 88 controls various engine control parameters to provide the desired engine torque.

Now back to the Pedal Input Interpretation module 80 Reference is made; the power request signal generated thereby 82 will also be sent to a real-time gear selector module 90 transmitted. The real-time gear selection module 90 receives the power request signal and a vehicle speed signal and generates a target gear signal 92 attached to the gearbox 16 from 2 or transmitted to a control module associated therewith. The gear of the transmission is based on the target gear signal 92 selected.

In 4 is the real-time gear selector module 90 from 3 illustrated in more detail. The real-time gear selection module 90 contains a torque and speed calculation module 102 to the torque and speed for all gears in the associated transmission 16 to calculate. The torque and speed calculation module calculates an engine speed signal for each gear 104 , The torque and speed calculation module 102 Also calculates a motor torque signal for each gear 106 , The torque and speed calculation module 102 Also calculates a turbine wheel speed signal for each gear 108 , The torque and speed calculation module 102 also calculates a turbine torque signal for each gear of the transmission 110 , The speed and torque signals 104 - 110 become a module 114 for choosing the optimal gear used to select a gear ratio that minimizes the later defined cost function within drivability constraints. The operation of this module will be described in more detail below. The output of the module 114 for the selection of the optimal gear is the target gear signal 92 ,

As in 5 is shown contains the torque and speed calculator 102 from 4 a turbine speed calculator 120 , The turbine speed calculator 120 generates a turbine wheel speed signal for each gear 122 , The transmission also includes a torque converter having a turbine wheel and impeller to couple the engine and the transmission. The vehicle speed signal 78 and the wheel circumference 124 the wheels become for a division block 126 provided. The wheel circumference 124 can one in memory 62 from 2 be stored constant. The vehicle speed, which is divided by the wheel circumference, gives the speed of the wheel. A multiplier block 128 multiplies the speed with the driveline ratio, which in turn is in a multiplier block 130 with the gear ratio 132 multiplied to provide it for a turbine wheel. The wheel circumference 124 , the final drive ratio 129 and the gear ratio 132 are all constants in the memory associated with the control module 62 or stored in the control module itself.

As in 6 can be shown, the torque and speed computer module 102 then the engine speed, the turbine torque, and the engine torque in an engine speed / torque and turbine torque computer module 150 to calculate. The module 150 can make a decision block 152 containing the turbine wheel speed 122 compared with that of a torque converter clutch. If the turbine speed is not higher than the speed that the Torque converter clutch applies, the power request signal 82 and the turbine speed signal 122 entered into a look-up table 160 to look up the engine speed from the disengaged torque converter clutch. The engine speed 162 is then output from the table 160. In addition, the power request signal 82 and the turbine speed signal 122 entered into another look-up table 164 to determine the turbine torque with the converter clutch disengaged. The lookup table 164 uses the power request signal 82 and the turbine speed 122 to a turbine torque signal 166 to determine. In addition, the power request signal determined in the box 167 divided by the engine speed signal, a motor torque signal 168 ,

If the turbine wheel speed in the box 152 is greater than the speed applied by the torque converter clutch, the engine speed is determined as the turbine speed plus the torque converter slip speed, the engine torque is determined as the power demand divided by the engine speed, and the turbine torque is determined by the engine torque multiplied by the efficiency in the block 170 , Finally, the engine speed signal 162 , the turbine wheel torque signal 166 and the engine torque from the torque and speed calculator into the module 114 specified for the choice of the optimal gear.

Now, with respect to 7 the module 114 for choosing the optimal gear explained in more detail. In general, a cost function calculation for each gear of the transmission in the block 210 executed. A deduction calculation module 212 calculates a deduction for each gear based on drive behavior limitations. The cost function module 210 generates a cost signal 214 and put it in an arithmetic block 216 one. The deduction calculation module 212 calculates a trigger signal 218 and put it in the arithmetic calculus block 216 one. The arithmetic calculus block 216 can multiply, divide, add or subtract the cost signal and the trigger signal, and ultimately determine final cost for each gear. A signal 220 for final costs will be in a comparison module or determination module 222 which determines the desired gear having the lowest final cost by comparing the final costs associated with each gear. Finally, in response to the block 222 put the transmission in the gear that has the lowest final cost.

In 8th is a first embodiment of a cost function 210A shown. It should be noted that each of the cost functions is performed for each of the gears in the transmission. In the first cost function, a look-up table 240 uses the engine speed signal 162 and the engine torque signal 168 to get an engine fuel rate signal 242 to create. The engine speed 162 and the engine torque 168 also be in the arithmetic block 244 multiplied by each other. The engine speed multiplied by the engine torque is used to calculate the engine power signal 246 to obtain. The fuel rate divided by engine power is used to calculate the cost signal 214A to get for each gear. Thus, in this case, the engine speed and the engine torque are ultimately in the cost signal 214A used.

In 9 is a second cost function 210B shown. In this example, the lookup table 240 uses the engine speed signal 162 and the engine torque signal 168 to like in 8th the engine fuel rate signal 242 to determine. In this example, however, the turbine wheel speed signal 122 and the turbine torque signal 166 into a multiplier block 250 entered to a turbine wheel power signal 252 to obtain. The engine fuel rate 242 is divided by the turbine wheel power to the cost signal 214B to obtain.

In 10 is a third embodiment for determining a cost function signal 210C shown. In this example, the engine fuel rate signal becomes 242 in the same way as in the 8th and 9 certainly. In this embodiment, the turbine torque signal becomes 166 with the gear ratio 132 multiplied by a power signal 260 to accomplish. In the arithmetic block 248 the fuel rate is divided by the power signal to the cost signal 214C to obtain.

In 11 is a similar embodiment to that of 10 shown. In this example, the fuel cost signal 214C generated and with a first weight 216 multiplied by a weighted cost signal 262 to get that used to be a total cost signal 264 to accomplish.

The total cost signal 264 also has an emission component for it. The engine speed signal 162 and the engine torque signal 168 are input to a look-up table 266 to generate a motor emission signal 268 to create the engine emission amount created by the system. The engine emission signal 268 is in the arithmetic block 272 with a second weight 270 multiplied by a weighted engine emission signal 274 to build. The weighted engine emission signal 274 and the weighted fuel cost signal 262 are added together to the final cost signal 264 in the block 276 to build. This can be done for each gear. Finally, the control module can determine the lowest cost for each gear.

In 12 For each gear, a deduction can be made. 12 shows a first embodiment of the deduction calculation of 7 at 212A , In this embodiment, the engine speed signal becomes 162 entered into a look-up table 310 for a maximum motor torque signal 312 to accomplish. The power request signal 82 is sent to a lookup table 314 for a torque reserve signal 316 to determine. The torque reserve signal 316 is generated from the lookup table and into an arithmetic block 318 entered, which is the torque reserve signal 316 and the signal 312 combined for maximum engine torque. The arithmetic block may be the torque reserve signal 316 from the signal 312 For maximum engine torque, subtract a torque signal 320 to obtain and admit. The approved torque signal 320 and the engine torque signal 168 be in a decision block 322 entered. The decision block determines if the engine torque is greater than the allowed torque. If the engine torque is greater than the allowed torque, block 324 a high deduction indicated. If in block 322 the engine torque is not greater than the permitted torque, is in the block 326 no deduction fixed.

In 13 is another embodiment 212B for determining costs. In this example, the power request signal becomes 82 entered into a look-up table 340 to receive the signal 342 for approved minimum engine speed. The engine speed signal 162 gets into a decision block 344 to determine if the engine speed is lower than the allowed engine speed. If the engine speed is lower than the allowed engine speed, then 346 activates a high-deduction flag. If the engine speed is not lower than the allowed engine speed, no deduction will be imposed and will be made in step 348 set a zero-off flag.

In 14 a third embodiment of a cost signal is determined. In this embodiment, a look-up table 370 is provided which contains the power request signal 82 used to get an approved maximum engine speed 372 to determine. The engine speed signal 162 and the allowed maximum engine speed signal 372 will be in a comparison block 374 which determines if the engine speed is greater than the allowed maximum engine speed. If the engine speed is greater than the allowed maximum engine speed, the block shows 376 a flag for high deduction. If in block 374 the engine speed is greater than the allowed maximum engine speed, is in the block 378 set a flag for no deduction.

Once the cost and loss signals are created receives 7 final cost for each of the gears. The gear with the minimum final cost is called the desired gear in the block 222 from 7 selected.

It should be noted that the above look-up tables can be easily determined from engine calibration tests. Many of the intermediate calculations are well known lookup table functions.

Claims (18)

A method of selecting a gear in a transmission (16) of a motor vehicle (10), comprising: Determining a power request signal (82) in response to a pedal position and a vehicle speed (78); Determining an engine speed (104, 162) of each gear in dependence on the vehicle speed (78) and the power request signal (82); Determining an engine torque (106, 168) of each gear in dependence on the vehicle speed (78) and the power request signal (82); Determining a transmission component speed (108, 122) of each gear in dependence on the vehicle speed (78) and the power request signal (82); Determining cost (214) for each gear using a cost function and in dependence on engine speed (104, 162) and engine torque (106, 168); Determining a penalty (218) for each gear based on drive behavior limitations and in response to the power request signal (82) and the engine speed (104, 162); Merging the respective costs (214) for each gear with the respective trigger (218) for each gear and thereby determining final costs (220) for each gear; such as Comparing the final cost (220) for each gear and selecting a gear with the lowest final cost (220). Method according to Claim 1 wherein determining cost (214) for each gear is further dependent on transmission component speed (108, 122). Method according to Claim 1 or 2 further comprising determining a transmission component torque (110, 166) of each gear in dependence on the vehicle speed (78) and Power request signal (82), wherein determining cost (214) for each gear is further responsive to transmission component torque (110, 166). Method according to Claim 1 further comprising determining an engine fuel rate (242) in dependence on the engine speed (104, 162) and the engine torque (106, 168), wherein determining cost (214) for each gear further depending on the engine fuel rate (242) he follows. Method according to Claim 4 further comprising determining an emission amount (268) in dependence on the engine speed (104, 162) and the engine torque (106, 168), wherein determining costs (214) for each gear further depending on the amount of emissions (268) he follows. Method according to Claim 1 wherein determining an engine speed (104, 162) of each gear further is dependent on the respective transmission component speed (108, 122) of each gear. A method of controlling a geared transmission (16), the method comprising: Determining a turbine speed (108, 122) for the transmission (16); Determining an engine speed (104, 162) in response to the turbine speed (108, 122) and a power demand; Determining an engine torque (106, 168) in response to the engine speed (104, 162) and the power demand; Determining cost (214) for each gear using a (214) cost function and in dependence on engine speed (104, 162) and engine torque (106, 168); Determining a penalty (218) for each gear based on drive behavior limitations and in dependence on the power demand and the engine speed (104, 162); Merging the respective costs (214) for each gear with the respective trigger (218) for each gear and thereby determining final costs (220) for each gear; such as Comparing the final cost (220) for each gear; and Controlling the transmission (16) so that the gear with the lowest final cost (220) is selected. Method according to Claim 7 and further comprising determining a turbine torque (110, 166) in dependence on the turbine speed (108, 122) or the engine torque (106, 168). Method according to Claim 8 wherein determining the cost (214) for each gear further is dependent on the turbine torque (110, 166) and the turbine speed (108, 122). Method according to Claim 8 wherein determining the cost (214) for each gear further is dependent on the turbine torque (110, 166), engine fuel rate (242), and gear ratio. Method according to Claim 7 wherein determining the cost (214) for each gear is further dependent on an engine fuel rate (242). Method according to Claim 7 wherein determining the trigger (218) for each gear further occurs in response to the engine torque (106, 168). Method according to Claim 7 wherein determining the trigger (218) for each gear further occurs in response to a maximum engine speed (104, 162) based on the power demand. Method according to Claim 7 wherein determining the trigger (218) for each gear further occurs in response to a minimum engine speed (104, 162) based on the power demand. A control system for a transmission (16) that communicates with a motor (18) and includes: a pedal input interpretation module (80) configured to determine a power request signal (82) in response to a pedal position and a vehicle speed (78); and a real-time gear selector module (90) in communication with the pedal input interpretation module (80) and configured to: determine an engine speed (104, 162) of each gear in response to the vehicle speed (78) and the power request signal (82); determining an engine torque (106, 168) of each gear depending on the vehicle speed (78) and the power request signal (82), a transmission component speed (108, 122) of each gear depending on the vehicle speed (78) and the power request signal (82) determining, wherein the real-time gear selector module (90) comprises a cost function module (210, 210A, 210B, 210C) arranged to generate a cost signal for each gear using a cost function and engine speed (104, 162) and engine torque (106, 168); wherein the real-time gear selector module (90) further comprises a trigger calculation module (212, 212A, 212B, 212C) configured to trigger a trigger signal from the power request signal (82) and the engine speed signal, an arithmetic calculator block (216) arranged to merge the cost signal for each gear with the respective trigger (218) for each gear and thereby a final cost signal (220) for each Gear and comprising a comparison module (222) arranged to compare the final cost signals (220) for each gear and to determine a gear with the lowest final cost (220), and wherein the real-time gear selector ( 90) is arranged to determine the gear with the lowest final cost (220) for a gear selection. Control system after Claim 15 wherein the cost function module (210, 210B) is arranged to further determine the cost signal for each gear in dependence on the transmission component speed (108, 122). Control system after Claim 15 wherein the deduction calculation module (212, 212B, 212C) is arranged to further generate the withdrawal signal in response to an allowed minimum engine speed (104, 162) or an allowed maximum engine speed (104, 162). Control system after Claim 15 wherein the cost function module (210, 210B, 210C) is arranged to further generate the cost signal for each gear depending on an engine fuel rate (242) and transmission component speed (108, 122) or transmission component torque (110, 166).

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