Patent Application
20060048516
This application claims priority from German Application Serial No. 10 2004 043 587.1 filed Sep. 9, 2004.
The invention relates to a device and a method for steering and regulating components of a hybrid driveline of a motor vehicle.
To further reduce the fuel consumption and emission of motor vehicles, the motor vehicle industry has sought further to develop hybrid driveline drafts known per se and, therefore, introduce suitable steering and regulating devices. For operating those steering and regulating devices, new steering and regulating methods are, in turn, needed which, due to their complexity, are designed as computer programs and work with the aid of computers, sensors and actuators related thereto.
From GB 2 340 463 A1, a vehicle is known, having a parallel hybrid driveline in which the driveline gears of the vehicle can be optionally driven by an internal combustion machine, an electric motor or simultaneously by both prime movers. A control device steers and regulates the use of the two prime movers on the basis of sensor information about, for example, the rotational speed of the internal combustion machine, the rotational speed of the electric motor, the state of charge of an electric energy accumulator, the traveling speed, the accelerator pedal deviation (by which the driver signals his desired drive torque), the actuation of the service brake, the selected gear of the transmission and the shift position of a switch with which the wish for a very quick start of the vehicle can be signalized. With the aid of the information, it is possible, for example, to implement a quick electromotive start of the vehicle and connect the drive to the combustion drive in the sense of a brief power increase of the whole input power of the vehicle.
Moreover, EP 0 903 259 B1 has disclosed a hybrid drive vehicle with a steering system for control of the input of the internal combustion machine and of the electric machine in which the steering system deduces the desired input of the driver from a deviation signal of the accelerator pedal. The steering system then calculates the needed input of the electric machine depending on the accelerator pedal value and the remaining electric capacity of an electric energy accumulator and then calculates one correction variable for the power control of the internal combustion machine in order thus to reduce the output power thereof so that the sum of the electric and the combustion input corresponds to the input required by the accelerator pedal deviation.
From EP 1 199 205 A2, different drivelines are known with coordinated steering and regulating devices and working with steering and regulating programs which optimize the hybrid operation of a motor vehicle regarding the energy currents in the driveline. At the same time are admitted a purely combustion driven, a purely electrically driven, the same as a vehicle drive, designed with both prime movers such as the regenerative operation of at least one electric machine.
In addition, the steering and regulating device decides how the actual operation states of the internal combustion machine and of the electric machine of the driveline are to be linked, respectively, with the accelerator pedal deviation of the vehicle driver and the speed of the vehicle. In addition, the steering and regulating device generates control signals for the internal combustion machine, the electric machine, a transmission continuously adjusting its reduction ratio and a coupling between the internal combustion machine and the electric machine to meet the performance designed by the driver.
For the purpose, this steering and regulating device has, at its disposal, a number of optional methods for steering and regulating the internal combustion machine, the electric machine and the clutch, the same as a number of methods for calculating the operating points for the internal combustion machine, the electric machine and the continuously variable transmission. Furthermore, the steering and regulating device comprises control means for control of the internal combustion machine, the electric machine, the clutch and the transmission.
It is decisive for the construction and utilization of this known steering and regulating device that with the aid of a so-called vehicle-state detector, it finds the actual driving state of the hybrid vehicle with reference, among others, to the accelerator pedal deviation, the traveling speed and the State of Charge (SOC) of an electric battery, the same as to the electric energy fed to or removed from it, determining on this basis the steering and regulation of the internal combustion machine, of the electric machine in its electrically driven and regenerative operation, the actuation of the clutch, the same as the ratio change characteristic of the automatic transmission.
From WO 02/26520 A1 is finally shown a driveline control for a motor vehicle having at least two drive units and one transmission by way of which the operation of a hybrid vehicle is to be improved relative to fuel consumption, emission, driveability and driving performance. According to this publication, this is achieved by a driveline control having at its disposal in the first place decentral steering units for generating setting signals for the drive unit and the transmission, the same as a so-called accelerator pedal interpretation device to determine a torque nominal value from one variable that characterizes the driver's wish.
To this driveline control also belongs an area designated as nominal state manager where the momentary nominal operating state of the driveline according to the torque nominal value and to the state of charge of an electric energy accumulator in the vehicle. Finally, the driveline control also comprises one area designated as torque manager in which, according to the torque nominal value and to the established nominal operating state of the driveline, individual control signals are generated for the above mentioned decentral control units.
This publication also discloses that the driveline control has, in addition, one area designed as driver and situation detection with which detected operating variables of the vehicle are evaluated, classified and can then be fed to the nominal state manager for determining the nominal operating state. This driver and situation detection can have, in particular the following component parts: one drive-type detection, one environment and road-type localization, the same as one driving manoeuver and driving situation detection.
Besides, it is known from the prior art that the nominal state manager has one configuration identifier which can be locked or released, according to the state or value of the configuration identified, nominal operating states of the driveline stored in the nominal state manager.
In the steering device, according to WO 02/26520 A1, it is disadvantageous that at least two prime movers in the combustion driven, electrically driven and/or one clutch, the same as one transmission in the hybrid driveline, are controlled and regulated only on the basis of values that identify the driver-type the same as the current driving situation. The actual state of charge of the electric energy accumulator is here accepted as a given variable.
In parallel hybrid vehicles, however, it is to be especially borne in mind that the State of Charge (SOC), for example, of an electric battery, has an optimum respectively for the electrically driven and the combined electrically driven and combustion driven operation. How the optimum of the state of charge is formed depends on the requirements of the driveline which are given, on one hand, by a rather dynamic driving mode and, on the other, by a rather economic driving mode. Thus, for a rather dynamic driving mode, it is convenient to have the battery constantly charged as completely as possible in order, with the aid of electrically driven assistance of a combustion driven motion (boosten), to be able to use even with comparatively small and power weak internal combustion machines, a clearly traceable power reserve or to make achieving a range in purely electrically driven operation as great as possible.
On the other hand, a rather economically oriented driving mode requires that, when needed, the battery be emptied to a convenient extent so as to be able, in the appropriate operating situations of the vehicle, to fill it by free recuperation energy. The latter is available, for example, when the vehicle moves forward without power while one of the electric machines of the vehicle is regeneratively driven by the vehicle drive gears via the transmission.
Accordingly, in a hybrid driveline with several connectable prime movers, an optimal distribution of the energy sources and energy countersinks have to be ensured in the vehicle driveline, which conveniently takes the driver's wish for a dynamic, an economic or intermediate operating mode of the vehicle into account.
Hence, the problem on which this invention is based is to propose a device and a method for steering and regulating a hybrid driveline of a motor vehicle in which, compared to the prior art, the power distribution control for the drive units engaged in the driveline is realized so as to accomplish a nominal drive torque of the vehicle required by the driver, the same as an optimal state of charge of the electric battery.
The solution of the problem for the steering device results form the features of the main claim and for the steering method from the features of claim 16. Advantageous developments and embodiments of the invention are to be understood from the respectively associated sub-claims.
The invention concerns a device for steering and regulating components of a hybrid driveline of a motor vehicle which has at least two prime movers, at least one clutch and one transmission. The steering and regulating device has the following parts: one device to determine a nominal drive torque from a variable signalizing the actual torque desired by the driver or from the preset nominal torque of an automatic nominal torque-definition device; one device for determining a sporting characteristic value; one device for establishing a nominal state of charge of an electric energy accumulator of the vehicle according to the nominal drive torque determined and the sporting characteristic value; one device for establishing the input distribution between at least two prime movers according to the established nominal state of charge so that the required nominal drive torque can be implemented and the nominal state of charge of the energy accumulator be maintained; and one device for generating and relaying steering and regulating signals for the two prime movers, at least one clutch, the same as the transmission.
The prime movers for which the steering and regulating device generates signals for steering and regulating are designed as one internal combustion machine and as at least one electric machine. The preferably two electric machines in the driveline are constructed so that one electric machine is designed electrically or driven with relatively higher power and the other electric machine electrically or regeneratively driven with relatively low-to-medium power and thus as so-called starter generator.
The electrically and regeneratively operable first electric machine is preferably operatively connected with an oil pump with which can be satisfied by the oil need or hydraulic pressure need of the individual driveline components, especially during start of the internal combustion machine; the same as during phases in the driving operation with relatively low power requirement in traction or coasting with the cut-off internal combustion machine.
The oil pump can be connected by way of a first clutch with the internal combustion machine so that for driving thereof in combustion-driven operation of the vehicle, the electric machine has not to run separately. The second electric machine is connected with the input shaft of the transmission, according to driving technology. By way of a second clutch, the input shaft of the internal combustion machine is, likewise, connectable with the transmission input shaft so that the transmission input shaft can be driven jointly and simultaneously by the internal combustion machine and the second electric machine.
In addition, the inventive steering and regulating device is preferably designed so that the sporting characteristic value can be ascertained by a shift position of a sporting switch or of a transmission selector lever or by a measuring value, which identified the accelerator pedal acceleration. It is known that from the actual value of the accelerator pedal acceleration can be determined whether the driver straightly steering the vehicle by soft accelerator pedal motions prefers a rather economic driving mode or, on account of hectic accelerator pedal deviation, rather a dynamic mode of driving.
Moreover, the steering and regulating device also comprises one device for determining a nominal drive torque, that is, the drive torque of the vehicle which the driver actually wishes. The nominal output torque can be, for example, the nominal output torque on the vehicle gears or also the one which would be measurable on the transmission output shaft.
To determine the nominal drive torque, the same as a nominal reduction ratio (nominal gear) for the transmission, the device of the steering and regulating device is equipped with electronic constant value accumulators and connected with sensor and/or data lines where this device is fed information concerning the following variables: the accelerator pedal deviation from whose timed deflection can be determined the accelerator pedal deviation speed and the acceleration; the actual gear and the target gear of the transmission; the unused capacity of the energy accumulator which is designed, for example, as battery or high-power capacitor (supercap); the actual torque; the target torque, and the maximum possible torque during the actual rotational speed of a prime mover.
The steering and regulating device preferably further comprises, for the parallel hybrid driveline, a device for determining the actual state of the driveline with which the actual states of actuators of at least one clutch of the prime movers and of the transmission can be detected, via sensor and/or data lines.
It is, moreover, provided that a device for establishing the input distribution can be informed by the device for determining a nominal drive torque about the nominal drive torque and about the sporting characteristic; the same as by the device for determining the actual state of the driveline a value can be fed concerning the actual state of the driveline.
Besides, it is a component part of the steering and regulating device that to the device for establishing the input distribution can be fed, in addition, from a electronic constant value accumulators and via sensor and/or data lines, information concerning the following variables: the minimum and maximum accumulator capacity of the electric energy accumulator; the maximum possible drive torque of at least one electric machine; the actual electric power of at least one electric machine; a transmission gear change status (that is, whether a ratio change operation has or has not taken place in the transmission); the actual operating state of a device for steering and regulating a first clutch coordinated with the starter generator (first electric machine), and the minimum rotational speed of the first electric machine with which the oil pump can cover the actual oil need or hydraulic pressure need in the driveline.
In the development of this device, it is preferably provided that the device for establishing the input distribution be constructed to be able to deliver, according to at least one of the variables fed, the following variables concerning data and/or steering lines: the nominal rotational speeds and nominal torques, the same as operating modes for the internal combustion machine and at least one electric machine; a switch blocking command to a switch blocking device, and an operating state nominal value to a device for control of the first electric machine designed as oil pump starter generator, the same as a device for control of the second clutch between the internal combustion machine and the second electric machine.
Furthermore, in another development of the invention of the steering and regulating device, there is preferably a decision device which balances the nominal standards of the device for establishing the input distribution with the output variables of the device for control of the second clutch, the same as of the device for control of the oil pump starter generator. Then it relays them to a device for transmission torque control adaptation when a change of state in the device for control of the second clutch and/or of the device for control of the oil pump starter generator does not lead to other nominal rotational speeds; nominal torques, the same as other modes of operation for the internal combustion machine and at least one electric machine.
According to another design of this steering and regulating device for the hybrid driveline, it is provided that the decision device be constructed so as to evaluate in its findings the data and/or signals of the devices herebelow in conformity with the following prioritization sequence:
This means that the operation of the oil pump, by way of the first electric machine, has priority in the driveline insofar as the oil pump is not driven, as usually, by the internal combustion machine. Insofar as the oil pump builds up a sufficient pressure medium accumulator, the steering and regulating standards have priority through the device for control of the second clutch, since in closed state, they make the purely combustion driven operation or the combined operation possible (that is, electrically driven boosting of the drive torque of the internal combustion machine), the same as in open state of the purely electrically driven operation with the second electric machine. Only when the superposed standards regarding the desired mode of operation of the driveline are taken into account, is the input distributed according to the device for establishing the input distribution.
In development of the inventive steering and regulating device, it is deemed advantageous that the device for transmission torque adaptation be designed so that, departing from the variables fed, it can deliver the rotational speeds and torques as nominal values for the internal combustion machine and for at least one electric machine.
Moreover, it is provided in this connection that the device for torque adaptation be designed for taking into account the additional torques of the electric machines and for taking into account the mass effects occurring as a result of different driveline states when determining the nominal values for the internal combustion machine and the nominal values for at least one electric machine.
In addition, the device for transmission torque adaptation is constructed so that it be suited to receive and process control signals of the transmission control unit with which, during operations for ratio change of the transmission, the prime movers of the driveline are controlled as to their rotational speed and torque delivery.
Finally, the device for transmission torque adaptation is constructed so that the rotational speed and the torque delivery of the prime movers can be adapted to the mass ratios of the precisely active hybrid driveline configuration during ratio change operations of the transmission.
The invention further relates to a method for steering and regulating components of a hybrid driveline of a motor vehicle having at least two prime movers, at least one clutch and one transmission. According to the invention, in such a driveline is provided that the driver's desired drive torque be distributed in nominal drive torques for the internal combustion machine and at least one electric machine and there be selected a mode of operation such that the state of charge of an electric energy accumulator is optimally adapted to the actual rather dynamic or rather economic driving mode of the driver.
According to a concrete embodiment of the method, the following steps are provided:
By this mode of operation is achieved that the state of charge of the energy accumulator of the driveline, that is, as a rule, an electric battery or electric capacitor, is always adapted to the dynamic or economic driving mode desired by the driver.
Thus, the driveline of the vehicle in a rather dynamic driving mode is essentially operated so that, when needed, a drive torque assistance of the internal combustion machine by the electric machine is possible (boosten). Therefore, care is taken as often as possible and needed that by a regenerative operation of the first electric machine and/or by a regenerative operation of the second electric machine, the energy accumulator is always well filled by operating as generator at least one electric machine. The operation also takes place, therefore, during combustion driven motion of the vehicle.
As far as the wish for a rather fuel sparing and emission poor mode of operation of the hybrid vehicle is determined, the state of charge of the energy accumulator is substantially kept in the medium-to-lower state of charge in order, preferably during the vehicle operation, for example, in coasting operation phases with internal combustion machine stopped and uncoupled from the driveline, to electrically charge the energy accumulator with recuperation energy to the extent that a subsequent purely electric drive of the vehicle is possible or the internal combustion machine can be assisted with high fuel consumption values regarding the total input torque of the vehicle in case of unfavorable operating points.
Therefore, according to the method introduced, the value of the nominal state of charge of the energy accumulator is a constant for a certain nominal input torque with a constant sporting characteristic value. This means that, differing from the known steering and regulating methods, it is not the actual driving situation that determines the state of charge of the vehicle, but the state of charge is preset for all driving situations as constant whose value depends essentially on which drive torque the driver actually wishes and which mode of driving he precisely prefers.
To the extent that the drive torque wish and/or the sporting characteristic value changes so is the value for the state of charge of the energy accumulator adapted. This finally results in that the components of the driveline are steered and regulated so as to reach the preset nominal value for the new state of charge.
Also considered advantageous in this connection is the other method feature according to which the sporting characteristic can be generated within limits such that therewith can be adjusted a nominal state of charge of the electric energy accumulator such that allows a complete emptying or a complete filling of the energy accumulator in electrically driven, combustion driven and combined driving phases only as long as this energy accumulator is not damaged in the process.
According to this method, the sporting characteristic value is determined by measuring the shift position of a sporting switch or of a transmission selector lever. But it is also possible to calculate the sporting characteristic value from secondary variables to which belong the measuring or calculation of the accelerator pedal acceleration over a predetermined period of time, the same as the subsequent evaluation thereof.
According to one other development of the steering and regulating method is provided that the nominal drive torque be determined by measuring and/or calculating at least the following variables: the accelerator pedal deviation; the actual gear and the target gear of the transmission; the actually unused capacity of the energy accumulator; the actual torque and the target torque of the prime movers, the same as the maximum possible torque of at least one of the prime movers at the precise actual rotational speed of the motor.
With the aid of the above mentioned variables, a nominal gear for the transmission is preferably also determined, which is subsequently fed via a switch blocking device to a transmission control unit or to a transmission control module.
It is further provided that the actual states of actuators of at least one automatically actuatable clutch, of at least one prime mover and of the transmission be determined. The transmission is here preferably an automatic transmission, the ratio change operations of which can be adjusted preferably by way of actuators operable by pressure medium.
According to the method for preparing the adjustment of the operating position of the respective clutch of the prime movers and of the transmission, the nominal input torque, the sporting characteristic value and the actual state of the driveline are communicated to a device for establishing the input distribution.
It is also provided that there be communicated to the device for establishing the input distribution, from constant value accumulators via sensor and/or data lines, information concerning the following variables: the minimum and maximum capacity of the energy accumulator; the maximum possible drive torque of at least one electric machine; the actual electric power of at least one electric machine; the gear change status of the transmission; the actual operating state of a device for steering and regulating a second clutch between the internal combustion machine, and the purely electrically operable electric machine; the same as the minimum rotational speed of the first electrically driven and regeneratively operable electric machine with which the oil pump can cover the actual need of oil or need of hydraulic pressure in the driveline.
According to another feature of the steering and regulating method, it can be provided that the device for establishing the input distribution, depending on at least one of the variables fed, delivers to the devices, via data and/or control lines, the following variables: the relaying of the nominal rotational speeds and nominal torques, the same as modes of operation for the internal combustion machine and at least one electric machine, to a decision device; a shift blocking command to a switch blocking device; a nominal value of operating state to a device for control of the first electric machine designed as an oil pump starter generator, the same as to a device for control of the second clutch between the internal combustion machine and the second electric machine.
In addition, it is preferably provided that the decision device tunes the nominal standards of the device for establishing the input distribution with the output variables of the device for control of the second clutch and the device for control of the starter generator of the oil pump and then relays them to a device for the transmission torque adaptation when actually occurring state changes in the device for control of the second clutch and/or the device for control of the starter generator of the oil pump do not lead to other nominal rotational speeds, nominal torques and/or other modes of operation for the internal combustion machine and at least one electric machine.
Another feature of the steering and regulating method is that the decision device works according to the following prioritization sequence:
By way of this prioritization, in particular, it is achieved that the oil pump be operated with priority so that, for example, for control of the actuators, there quickly and always abuts on the components of the hybrid driveline, a sufficiently high hydraulic pressure and a sufficiently large amount of oil is available.
One other component part of the steering and regulating method is that subsequent to a transmission torque adaptation that optionally occurred, the rotational speeds and torque determined are relayed as nominal values for the internal combustion machine and as nominal values for at least one electric machine to the machines or to control units coordinated therewith.
When adapting the transmission torque that depends on the current mode of operation of the driveline (purely electrically driven, purely fuel driven, fuel driven and regeneratively fuel driven and electrically driven), added torques and mass effects of the respective components coupled to the driveline are taken into account when determining the nominal values of the internal combustion machine and nominal values for at least one electric machine.
Besides, it is provided for the transmission torque adaptation that control signals of the transmission control unit are processed with the aid of which, during ratio change operations of the transmission, the prime movers are controlled regarding their rotational speed and torque delivery. As example, let it be mentioned here that the rotational speed reduction, known per se, of the prime mover when a gear upshift is carried out in an automatic transmission.
Finally, it is preferably provided that when adapting the transmission torque during ratio change operations of the transmission, the rotational speed and torque delivery of the prime movers are adaptable to the mass ratio of the precisely active hybrid line configuration.
The invention will now be described, by way of example, with reference to the accompanying drawings in which:
As can be understood from the Figures, the inventive steering and regulating device, the same as the steering and regulating method, can advantageously be used in parallel hybrid drivelines of different construction for motor vehicles.
In this embodiment, a torque generated by the internal combustion machine VM is relayed via a crankshaft 3 thereof to a torsional vibration damper 4 which, as known per se, dampens the torsional irregularities produced by the operation of the internal combustion machine VM and then relays the input torque via its output part 5. According to driving technology, one actuator-operable clutch K2 is situated downstream of the torsional vibration damper 4; the output side of which is rotatably connected with the input shaft of an electric machine EM2 and with an input shaft 6 of the automatic transmission 7. Such a parallel hybrid driveline is known and, therefore, its mode of operation will be only briefly described.
In the purely combustion driven operation, the crankshaft 3 of the internal combustion machine VM actuates the transmission input shaft 6 when a clutch K2 is closed. One control unit 20 adjusts different ratio steps in vehicle operation in the automatic transmission 7 whereby the different input torques and the input rotational speeds can be implemented on the transmission output shaft.
In the purely electrically driven operation, the clutch K2 is open and the electric machine EM2, energized by an electric energy accumulator 28 and controlled by a control unit 12, drives the transmission input shaft 6 with a desired input torque. Also in this mode of operation, the transmission 7 works as described above.
In a third mode of operation, the internal combustion machine VM and the electric machine EM2 jointly drive the transmission input shaft 6 when the clutch K2 is closed so that, for example, even a vehicle of comparatively weak performance and consumption poor, internal combustion engine VM can be operated in certain operating situations with a clearly increased input torque.
In a fourth mode of operation, the internal combustion machine VM is disconnected when the vehicle is rolling and the clutch K2 open so that the electric machine EM2 is driven by the drive gears of the vehicle via the transmission 7. The electric machine EM2 works as a generator in this mode of operation so that the electric energy generated can be advantageously guided into the energy accumulator 28.
Also to this second drive 2 belongs one other clutch K1, the input part of which is in operative connection with the output 5 of the torsional vibration damper 4. The output of this clutch K1 is in rotatable connection with the input shaft 9 of the oil pump 8 and the input shaft of the electric machine EM1.
Differing from the mode of operation of the driveline 1 in
In addition, this driveline 2, where the electric machine EM1 is laid out preferably weaker in performance than the electric machine EM2, allows the driving of the oil pump 8 even in those operation phases of the vehicle where the internal combustion machine VM is cut-off and uncoupled from the driveline 2, the same as the electric machine EM2 works regeneratively and supplies an electric current to the energy accumulator 28.
Moreover, it is possible to design both electric machines EM1 and EM2 as starter generators so that when the clutches K1 and K2 are closed, during combustion driven motion, the electric energy accumulator 28 can be charged by way of both electric machines in a quick charge phase.
Finally, in one other mode of operation, when the clutch K1 and K2 are closed, it is possible to allow the internal combustion machine VM and both electric machines EM1 and EM2 to generate a joint torque which acts upon the transmission input shaft 6, same as in a last mode of operation. It is convenient to use the electric machine EM1 as a starting motor for the internal combustion machine VM when the clutch K1 is closed and the clutch K2 is open.
The invention concerns the interaction of the steering and regulation of the internal combustion machine VM of the electric machines EM1 or EM2 of the clutches K1 or K2 and of the automatic transmission 7 in a manner such that, on one hand, the input torque desired by a vehicle driver acts upon the vehicle drive gears. This input torque is implemented by interaction of the prime movers VM, EM1 and EM2 in a manner such that the vehicle is operated poor in emission, sparing in fuel and in the mode of operation desired by the driver (rather dynamic or rather economic).
For further clarification of the invention, herebelow are explained system models of the above described drivelines 1 and 2 which, in a simplified manner, represent the interaction of the driveline components with the control devices coordinated therewith.
As this graph makes clear, the internal combustion machine VM generates an input torque M_VM which, when the clutch K2 is closed, is relayed as clutch torque M_K2 to the input side of the electric machine EM2. Insofar as this rotates along not only idle but being effective as electric motor, the electric machine EM2 generates an input torque M_EM2 which, together with the input torque M_VM of the internal combustion machine VM, forms an input torque M_GE on the transmission input shaft 6. After ratio related change in the transmission 7 and in the differential transmission 18, the desired input torque of the vehicle then abuts on the vehicle gears.
As
Moreover, it can be seen that the electric machine EM2 is connected, for example, via the control unit 12, with ane electric circuit 15 of the vehicle, the same as via unavoidable specific resistances 16 with the electric energy accumulator 28 from which and in which the electric machine EM2 can guide an electric current.
As
The two
As already indicated, the invention can be implemented as steering and regulating method operated in several decentral computers. But it is also possible that the inventive steering and regulating method be implemented in a single computer by using separate accumulators, input and output areas, calculation modules and comparison modules, the necessary sensor information about the measuring values of individual sensors or vehicle components being supplied to the computer or computers, the same as thereby triggered commands for actuation of actuators.
According to
For determining the nominal drive torque fahr_soll_m and the sporting value kSport, a series of constants, sensor information and/or intermediate values from other steering devices are supplied to the deice 22, 23 to which belong, for example, the angle value of an acceleration pedal deviation, the deviation speed thereof and/or the deviation acceleration thereof. The values related to the accelerator pedal are here summarized under the expression “accelerator pedal”. To this device 22, 23 is further supplied the precise actual reduction ratio actual gear of the transmission, the same as the new reduction ratio target gear desired by the driver or automatically preset by a separate device (transmission control unit). As added variables are supplied: an actual input torque fahr_ist_m of the vehicle, a nominal input torque fahr_ziel_m of the vehicle, a maximum input torque fahr_max_m [wist] of the vehicle possible at the actual rotational speed and an electric power reserve cap_energiereserve of the electric accumulato
From the above mentioned variables, the device 22, 23 generates the actual nominal input torque value fahr_soll_m and the actual sporting value kSport which are supplied to a device 24 for establishing the input distribution. In addition, the device 22, 23 generates a value by the name of nominal gear for a new transmission reduction ratio which, as intermediate value, is supplied to a shift prevention device 29.
In a device 26 for actual state definition, the actual state of the vehicle or at least of the driveline 1 or 2 is furthermore determined by way of the following information: actual states k1_zu_b and k2_kfl_b of actuators of at least one clutch K1 or K2, an operation state vm_laeuft_b (running or stationary) of the internal combustion machine VM and an operation state getr_kf_b of the transmission 7.
This device 26 of determining the actual state of the driveline, after evaluation of the above mentioned information, delivers a variable pas_z to the device 24 for establishing the input distribution which is used therefor determining other intermediate variables.
It is also provided that the device 24 for establishing the input distribution receives from constant value accumulators and/or via sensor and/or data lines information supplied concerning the following variables: a minimum capacity cap_min_p and a maximum capacity cap_max_p of the energy accumulator 28, a maximum possible input torque em2_max_m of at least one electric machine EM1 or EM2, an actual electric power em2_el_p of at least one electric machine EM1 or EM2, a transmission gear change status getr_aktiv_b_[lock], an actual operation state k2manager_z of the clutch K2 between the internal combustion machine VM and the electric machine EM2 and a minimum rotational speed oel_min_n of the first electric machine EM1 with which the oil pump 9 can cover the oil and hydraulic pressure need in the driveline 2.
For establishing the input distribution, the task of the device 24 can be classified in two sub-ranges. In one so-called power manager, from the variable (but, in particular, by the nominal input torque fahr_soll_m and the sporting value kSport) can be established the power distribution regarding the prime movers involved in the driveline. The modes of operation of the prime movers can also be determined with regard to torque delivery and input rotational speed.
A second function of the device 24 is to determine which state of the drive system would be optimal for the required performance. To this end, the appertaining marginal conditions of the different driving modes, such as purely combustion driven, purely electrically driven, combustion driven and electrically driven, purely regenerative with operation of the internal combustion machine, are individually examined as to how an optimal mode of operation can be implemented under the existing marginal conditions. If the optimal mode of operation for the preset marginal conditions is given, it is established as nominal state and locked for a new nominal state change until either the actual state has become equal to the nominal state or a change of the actual state (for example, by a transmission selector engagements which change the flow of transmission energy)_has occurred in the meantime.
To establish the input distribution, accordingly, determined from the above variable, the device 24 the following variables which are delivered via data and/or control lines to the likewise mentioned steering and regulating devices that follow:
Nominal rotational speeds “nominal rotational speeds”, nominal torques “nominal torques” and modes of operation “nominal modes” for the internal combustion machine VM and at least one electric machine EM1 or EM2 are delivered to a decision device 31 for prioritizing the operation of at least one of the two electric machines EM1 and EM2, the same as of the internal combustion machine VM, a shift preventing command “shift prevention” is delivered to the shift prevention device 29 and an operation state nominal value pas sol_z to a device 25 for control of the electric machine EM1 designed as an oil pump starter generator, the same as to a device 30 for control of the second clutch K2 between the internal combustion machine VM and the second electric machine EM2. This device 30 for control of the second clutch K2 delivers in this connection control standards K2_soll_z and K2_soll_m to a clutch control module 37 for the clutch K2.
By way of the shift preventing device 29, the value for the nominal gear is relayed in this case as a nominal gear, according to
As it can be further understood from
The device 25 thereby makes possible for control of the electric machine EM1 designed as oil pump starter generator to ensure the oil supply in the driveline 2; to effect a kind of vibration of the internal combustion machine VM while the vehicle stands still or rolls; to carry out the synchronization and separation of the electric machine EM1 and the internal combustion machine VM;
In the decision device 31, the tasks, which can also be distributed among separate decision devices EM1-Prio, EM2-Prio, VM-Prio, the nominal standards of the device 24 for establishing the input distribution, and of the device 25 for control of the electric machine EM1, designed as oil pump starter generator, are then tuned with the output variables of the device 30 for control of the second clutch K2.
The prioritization taking place in this device 31 establishes that the nominal standards of the device 24 for establishing the input distribution always have the first priority when no state changes in the device 30 for control of the clutch K2 and/or the device 25 for control of the electric machine EM1, designed as oil pump starter generator, lead to nominal rotational speeds “nominal rotational speeds”, nominal torques “nominal torques”, the same as other modes of operation “nominal modes” for the internal combustion machine VM and at least one electric machine EM1, EM2 which differ therefrom.
The decision device 31 here works preferably according to the following prioritization sequence:
Then follows a relay of prioritized decisions for driveline control to a device 27 for transmission rotational speed adaptation. This control module has the task of delivering to the transmission control 20 or the actuators thereof the interface values known from conventional drivelines such as motor torque and motor rotational speed of the respective prime movers. To this end are correspondingly taken into account optionally existing additional torques of the electric motors EM1 and EM2, same as the mass effects occurring due to different driveline states. Thereby result for the transmission control or a conventional transmission control unit variables known per se regarding the torque abutting on the transmission input shaft 6 and the transmission input rotational speed.
By this procedure, the software development expense and the application expense for a hybrid driveline related thereto are kept advantageously low, since the software fed to the conventional transmission control unit 20 can, to a great extent, be left unchanged independently of whether a hybrid driveline, according to
Moreover, let it be mentioned that the device 27 for torque adaptation also assumes the function of adapting control commands egs_eingriff_m issued by the transmission control during ratio change operations to the internal combustion machine or, in addition, to the electric machines EM1 and EM2, for example, to the end of an input rotational speed reduction of the transmission input shaft during an upshift operation, in a manner such that there be taken into account the different mass effects occurring in the respective modes of operation of the drivelines 1 or 2 when determining nominal values VM-standards for the internal combustion machine VM and the nominal value EM1-standards, EM2-standards for the electric machines EM1, EM2 regarding their rotational speed and torque delivery.
The device 27 for transmission torque adaptation gives the standard values EM1-standards, VM-standards, EM2-standards and Getr-standards to separate control modules 33, 34, 35 and 36 for the control of actuators which process the standard values to concrete control commands to the internal combustion machine VM, the transmission 7 and both electric machines EM1, EM2. Thus, for example, the command for starting and shutting-off the internal combustion machine VM can be generated in the control module 34.
There are such control modules 32 and 37 for both clutches K1 and K2. The standard values stem here, as mentioned above, from the device 25 for control of the starter generator (electric machine EM1 with coordinated clutch K1) or from the device 30 for control of the second clutch K2. In the control modules 32, 37 is preferably taken up the transformation of nominal slip torque values to physical correcting variables like clutch regulating distance and clutch actuation pressure. If additional state changes are to be effected in the clutch actuators (for example, idle stroke overcoming and application of the clutch such as with ramp control functions), these are effected, likewise, automatically in the clutch control modules 32 and 37.
All control modules 32 to 37 also generate already mentioned state variables which define the precisely existing actuation state of the actuators and define as a whole the total driveline state.
The above statements make clear that an inventively designed steering and regulating device or a steering and regulating method related thereto can be used at very favorable cost and with flexibility without expense in changes in different hybrid drivelines 1, 2. The existing steering and regulating software for an internal combustion machine and an automatic transmission can also be used without interface problems to be expected.
In the operation of an inventive steering and regulating device and of a steering and regulating method relative thereto, however, it is of particular advantage that, differing from known technical solutions, the actually existing driver's desire regarding the vehicle input torque and the precisely desired operating mode of the vehicle, that is rather dynamic or rather economic, is included in the steering and regulating of the driveline components. Besides, the state of charge of the electric energy accumulator 28 of the vehicle, the same as the emptying and charging thereof, are made dependent on the above mentioned marginal conditions. The respective optimal state of charge of the energy accumulator is reached for each operation mode, whether rather dynamic or rather economic.
37 clutch control module K2
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2004 043 587.1 | Sep 2004 | DE | national |
