EP2576306A1 - Method for operating a drive train - Google Patents

Method for operating a drive train

Info

Publication number
EP2576306A1
EP2576306A1 EP11711894.3A EP11711894A EP2576306A1 EP 2576306 A1 EP2576306 A1 EP 2576306A1 EP 11711894 A EP11711894 A EP 11711894A EP 2576306 A1 EP2576306 A1 EP 2576306A1
Authority
EP
European Patent Office
Prior art keywords
braking torque
electric machine
retarder
wear
output
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP11711894.3A
Other languages
German (de)
French (fr)
Inventor
Jürgen Blaser
Markus Eisele
Yvonne Wiegand
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ZF Friedrichshafen AG
Original Assignee
ZF Friedrichshafen AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ZF Friedrichshafen AG filed Critical ZF Friedrichshafen AG
Publication of EP2576306A1 publication Critical patent/EP2576306A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L7/00—Electrodynamic brake systems for vehicles in general
    • B60L7/10—Dynamic electric regenerative braking
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W20/00—Control systems specially adapted for hybrid vehicles
    • B60W20/10—Controlling the power contribution of each of the prime movers to meet required power demand
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L50/00—Electric propulsion with power supplied within the vehicle
    • B60L50/10—Electric propulsion with power supplied within the vehicle using propulsion power supplied by engine-driven generators, e.g. generators driven by combustion engines
    • B60L50/16—Electric propulsion with power supplied within the vehicle using propulsion power supplied by engine-driven generators, e.g. generators driven by combustion engines with provision for separate direct mechanical propulsion
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L7/00—Electrodynamic brake systems for vehicles in general
    • B60L7/24—Electrodynamic brake systems for vehicles in general with additional mechanical or electromagnetic braking
    • B60L7/26—Controlling the braking effect
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/58—Combined or convertible systems
    • B60T13/585—Combined or convertible systems comprising friction brakes and retarders
    • B60T13/586—Combined or convertible systems comprising friction brakes and retarders the retarders being of the electric type
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W10/00—Conjoint control of vehicle sub-units of different type or different function
    • B60W10/04—Conjoint control of vehicle sub-units of different type or different function including control of propulsion units
    • B60W10/08—Conjoint control of vehicle sub-units of different type or different function including control of propulsion units including control of electric propulsion units, e.g. motors or generators
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W10/00—Conjoint control of vehicle sub-units of different type or different function
    • B60W10/18—Conjoint control of vehicle sub-units of different type or different function including control of braking systems
    • B60W10/196—Conjoint control of vehicle sub-units of different type or different function including control of braking systems acting within the driveline, e.g. retarders
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W30/00—Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
    • B60W30/18—Propelling the vehicle
    • B60W30/18009—Propelling the vehicle related to particular drive situations
    • B60W30/18109—Braking
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2240/00—Control parameters of input or output; Target parameters
    • B60L2240/40—Drive Train control parameters
    • B60L2240/42—Drive Train control parameters related to electric machines
    • B60L2240/423—Torque
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2260/00—Operating Modes
    • B60L2260/20—Drive modes; Transition between modes
    • B60L2260/26—Transition between different drive modes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W20/00—Control systems specially adapted for hybrid vehicles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W2710/00—Output or target parameters relating to a particular sub-units
    • B60W2710/08—Electric propulsion units
    • B60W2710/083—Torque
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/64—Electric machine technologies in electromobility
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/70—Energy storage systems for electromobility, e.g. batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/7072—Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Definitions

  • the invention relates to a method for operating a drive train of a motor vehicle according to the preamble of claim 1.
  • the present invention relates to a method for operating a drive train with a hybrid drive.
  • a hybrid drive comprises at least one electric machine and one internal combustion engine.
  • a powertrain of a hybrid vehicle includes a transmission, wherein the transmission converts speeds and torques, thus providing a traction power supply of the hybrid drive to an output of the hybrid vehicle.
  • a drive train of a hybrid vehicle comprises a brake system, wherein it is already known from the prior art that a brake system may comprise a plurality of partial brake systems, namely a so-called service brake, which acts on friction wheels on the output, and at least one wear-free retarder.
  • the wear-free retarder may be a so-called engine brake or a retarder of the drive train.
  • the braking torque between the or each electric machine of the hybrid drive and the or each wear-free retarder split such that at the beginning of a braking torque request, the braking torque requested exclusively by at least one electric machine of the hybrid drive and provided at the output and, subsequently, depending on characteristics of the or each wear-free retarder, the brake torque request is at least partially transferred from the or each electric machine to at least one wear-free retarder such that the braking torque provided at the output by the or each electric machine and the or each retarder Sum corresponds to the requested braking torque.
  • the present invention it is proposed for the first time to divide a brake torque requirement on a brake system of a hybrid vehicle between the or each electric machine of the hybrid drive and the or each wear-free retarder of the brake system, namely such that at the beginning of a braking request, the braking torque exclusively from at least one electric machine the hybrid drive is requested and provided at the output. Only then, depending on parameters of the or each wear-free retarder brake torque request is at least partially controlled by the or each electric machine controlled at least one wear-resistant retarder of the brake system. This is done such that the output provided by the or each electric machine and the or each retarder braking torque in total corresponds to the requested braking torque.
  • a braking torque request it is thus possible with the method according to the invention to provide at least one electric machine of the hybrid drive directly with high dynamics and within a short time at the output a braking torque ready and thus to respond directly to a braking torque request. Subsequently, the braking torque request is controlled reduced at the respective electric machine of the hybrid drive and at the same time increased at least one wear-free retarder of the brake system, so as to build a controlled from the respective wear-resistant retarder at the output braking torque.
  • the braking torque which is controlled by the respective wear-free retarder at the output is reduced by the braking torque provided by the or each electric machine at the output.
  • the brake torque request from the or each wear-free retarder is transferred back to at least one hybrid drive electric machine, again controlled so that the output provided by the or each electric machine and the or each wear-free retarder Braking torque in total corresponds to the desired or requested braking torque.
  • FIG. 1 is a block diagram of an exemplary powertrain for
  • FIG. 2 shows a first diagram for further clarification of the method according to the invention
  • Fig. 4 is a third diagram for further clarification of the method according to the invention.
  • FIG. 1 shows by way of example a drive train diagram of a drive train of a hybrid vehicle in which the method according to the invention can be used.
  • the drive train of FIG. 1 has an internal combustion engine 1 and an electric machine 2, which together form a hybrid drive 3 of the drive train.
  • a transmission 5 and a retarder 6 are connected according to FIG. 1, whereby the retarder 6 is a wear-resistant retarder.
  • the retarder 6 is connected between the electric machine 2 of the hybrid drive 3 and the transmission 5.
  • the retarder 6 is connected between the transmission 5 and the output 4 or between the internal combustion engine 1 and the electric machine 2.
  • the method according to the invention is not restricted to the application on the drive train shown in FIG. Rather, the invention can be used on other powertrains of hybrid vehicles, for example, when the internal combustion engine and electric machine of the hybrid drive act on different axes of the output of the hybrid vehicle.
  • a drive train of a hybrid drive comprises a brake system, via which a braking torque can be provided at the output 4.
  • a brake system of the hybrid vehicle comprises a service brake, which acts on the wheels of the output 4 via friction.
  • the brake system of a hybrid vehicle comprises at least one wear-free retarder, wherein this wear-free retarder can be, for example, the retarder 6 shown in FIG.
  • Another wear-free retarder of a brake system of a hybrid vehicle is provided by a so-called engine brake of the internal combustion engine 1.
  • the requested braking torque is divided at least between the or each electric machine 2 of the hybrid drive 3 and the or each wear-free retarder.
  • This division of the requested braking torque is such that at the beginning of a braking torque request, the braking torque is requested exclusively by at least one electric machine 2 of the hybrid drive 3 and provided at the output 4, and that subsequently depending on characteristics of the or each wear-free retarder the braking torque request of the or each electric machine 2 of the hybrid drive 3 is passed controlled at least one wear-free retarder 6, so that the output provided by the or each electric machine 2 of the hybrid drive 3 and the or each retarder braking torque in total corresponds to the requested braking torque.
  • FIG. 2 showing a plurality of time curves over the time t, namely a time curve of a rotational speed n A B of the output 4 of the drive train, a time curve M B of one having a Braking torque request requested braking torque, a time curve M R of the retarder 6 at the output 4 provided braking torque and a time curve M E M one of the electric machine 2 at the output 4 provided braking torque.
  • a braking torque request M B for a to be provided on the output 4 braking torque is in Fig. 2, a braking torque request M B for a to be provided on the output 4 braking torque.
  • this braking torque request is requested exclusively by the electric machine 2, so that at the beginning of the braking torque request, ie immediately after the time t1, the requested braking torque M B exclusively via that of the electric Machine 2 providable braking torque M E M is provided at the output 4. Only subsequently, namely in Fig.
  • the partial transfer of the braking torque request from the electric machine 2 of the hybrid drive 3 to the retarder 6 and the wear-free retarder occurs in Fig. 2 between the times t2 and t3 respectively ramped or linear, ie, that between the times t2 and t3 on the one hand the Braking torque required by the electric machine 2 of the hybrid drive 3 ramp-reduced and the braking torque request of the wear-free retarder, namely the retarder 6, is ramped, and so also provided by the same at the output 4 braking torque M E M and MR.
  • FIG. 3 shows a development of the method according to the invention for the case in which the output rotational speed n A B is progressively reduced.
  • This refinement of the method according to the invention is based on the finding that the retarder 6 can no longer provide any braking torque at the output 4 when it falls below a minimum rotational speed.
  • the brake torque request on the retarder 6 continuously, preferably ramp-like, and thus controlled reduced and accordingly on the electric machine 2 of the hybrid drive 3 continuously, preferably ramp-like, and controlled increases, so that of the retarder 6 and the electric machine 2 in total at the output 4 provided braking torque in turn corresponds to the requested braking torque M B.
  • the point in time t4, from which the braking torque request is transmitted from the retarder 6 back to the electric machine 2 with increasing reduction of the output rotational speed n A B, can be determined in advance in advance depending on parameters of the retarder 6.
  • the procedure is such that during the braking torque request and thus during the execution of the braking the current output speed n A B is monitored at the output 4 and dependent thereof in terms of a control observation of the time t4, from which the torque transfer from the retarder 6 to the electric Machine 2 begins to be determined online while the brake torque request is being executed. From the time t5, from which the retarder 6 can no longer provide braking torque M R at the output 4, only the electric machine 2 provides a corresponding braking torque M E M at the output 4.
  • the braking torque M E M provided by the same is reduced to zero and then the requested braking torque of a service brake of the brake system, in particular via friction on the wheels of the output 4 acts, provided.
  • FIG. 4 shows a variant of the invention in which a braking torque request is divided between the electric machine 2 of a hybrid drive and two wear-free partial brakes of the braking system of the hybrid vehicle, namely between an engine brake and a retarder.
  • Fig. 4 shows the rotational speed n A B of the output 4 of a hybrid vehicle torque curves, namely the speed-dependent curve of a requested braking torque MB, the speed-dependent course of a provided by the electric machine 2 of the hybrid drive at the output 4 braking torque M E M, the speed-dependent curve one of an engine brake on the output 4 provided braking torque M M B, and the speed-dependent torque curve of the retarder at the output 4 provided braking torque M R.
  • Fig. 4 shows the rotational speed n A B of the output 4 of a hybrid vehicle torque curves, namely the speed-dependent curve of a requested braking torque MB, the speed-dependent course of a provided by the electric machine 2 of the hybrid drive at the output 4 braking torque M E M, the speed-dependent curve one of an engine brake on the output 4 provided braking torque M M B, and the speed-dependent torque curve of the retarder at the output 4 provided braking torque M R.
  • the lack of dynamics of the retarder and the engine brake can be compensated.
  • the requested braking torque is initially provided at the output 4 via at least one electric machine 2 of the hybrid drive 3.
  • brake torque is developed at the output via the wear-free retarder, in particular via a retarder or optionally an engine brake.
  • the retarder or the engine brake depending on the output speed of the output can no longer provide braking torque
  • the retarder or the engine brake is driven out of the braking intervention on the output 4, while then the or each electric machine 2 of the hybrid drive 3 in the regenerative Operation assumes the reduced braking torque request at the respective wear-free retarder and provides the corresponding braking torque at the output.

Landscapes

  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Power Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Automation & Control Theory (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Electric Propulsion And Braking For Vehicles (AREA)
  • Hybrid Electric Vehicles (AREA)

Abstract

Method for operating a drive train having a hybrid drive (3) which comprises at least one electric machine (2) and one internal combustion engine (1), a transmission (5), an output (4) and a brake system which comprises at least one wear-resistant permanent brake (6), wherein, when a braking torque for the output (4) is requested, the braking torque is distributed between the electric machine (2), or each electric machine (2) of the hybrid drive and the wear-resistant permanent brake (6) or each wear-resistant permanent brake (6) in such a way that at the start of a braking torque request the braking torque is requested exclusively from at least one electric machine (2) and made available at the output (4), and that subsequently, the braking torque request is transferred at least partially from the electric machine or from each electric machine to at least one wear-resistant permanent brake (6) controlled as a function of characteristic variables of the wear-resistant permanent brake or of each wear-resistant permanent brake, with the result that the braking toque which is made available at the output (4) by the electric machine or each electric machine of the permanent brake or of each permanent brake corresponds in total to the requested braking torque.

Description

Verfahren zum Betreiben eines Antriebsstranqs  Method for operating a drive train
Die Erfindung betrifft ein Verfahren zum Betreiben eines Antriebsstrangs eines Kraftfahrzeugs nach dem Oberbegriff des Anspruchs 1 . The invention relates to a method for operating a drive train of a motor vehicle according to the preamble of claim 1.
Die hier vorliegende Erfindung betrifft ein Verfahren zum Betreiben eines Antriebsstrangs mit einem Hybridantrieb. Ein solcher Hybridantrieb umfasst mindestens eine elektrische Maschine und einen Verbrennungsmotor. Zusätzlich zum Hybridantrieb umfasst ein Antriebstrang eines Hybridfahrzeugs ein Getriebe, wobei das Getriebe Drehzahlen und Drehmomente wandelt und so ein Zugkraftangebot des Hybridantriebs an einem Abtrieb des Hybridfahrzeugs bereitstellt. Ferner umfasst ein Antriebsstrang eines Hybridfahrzeugs ein Bremssystems, wobei es aus dem Stand der Technik bereits bekannt ist, dass ein Bremssystems mehrere Teilbremssysteme umfassen kann, nämlich eine sogenannte Betriebsbremse, die über Reibung auf Räder des Abtriebs einwirkt, sowie mindestens eine verschleißfreie Dauerbremse. Bei der verschleißfreien Dauerbremse kann es sich um eine sogenannte Motorbremse oder auch um einen Retarder des Antriebsstrangs handeln. The present invention relates to a method for operating a drive train with a hybrid drive. Such a hybrid drive comprises at least one electric machine and one internal combustion engine. In addition to the hybrid drive, a powertrain of a hybrid vehicle includes a transmission, wherein the transmission converts speeds and torques, thus providing a traction power supply of the hybrid drive to an output of the hybrid vehicle. Furthermore, a drive train of a hybrid vehicle comprises a brake system, wherein it is already known from the prior art that a brake system may comprise a plurality of partial brake systems, namely a so-called service brake, which acts on friction wheels on the output, and at least one wear-free retarder. The wear-free retarder may be a so-called engine brake or a retarder of the drive train.
Aus der DE 198 43 580 A1 ist eine Bremsanlage eines Kraftfahrzeugs bekannt, bei welcher eine angeforderte Bremskraft bzw. ein angefordertes Bremsmoment zwischen der Reibungsbremse der Bremsanlage und der Dauerbremse derselben aufgeteilt wird. Nach diesem Stand der Technik wird vorgeschlagen, dass beim Betätigen der Dauerbremse die Reibungsbremse mit einem Druck beaufschlagt wird, der zunächst einem Signal eines Bremswertgebers entspricht und mit zunehmender Bremskraft der Dauerbremse so verringert wird, dass die gesamte Bremskraft dem Signal des Bremswertgebers entspricht. Hiermit wird die Reibungsbremse mit einer kurzen Ansprechzeit voll wirksam, während bei längerem Bremsen die Dauerbremse die volle Bremsleistung übernimmt und die Reibungsbremse vor Überlastung schützt. Hiervon ausgehend liegt der vorliegenden Erfindung das Problem zu Grunde, ein neuartiges Verfahren zum Betreiben eines Antriebsstrangs zu schaffen. From DE 198 43 580 A1 discloses a brake system of a motor vehicle is known, in which a requested braking force or a requested braking torque between the friction brake of the brake system and the continuous brake of the same is divided. According to this prior art, it is proposed that upon actuation of the retarder, the friction brake is acted upon by a pressure which initially corresponds to a signal of a brake value transmitter and is reduced with increasing braking force of the retarder such that the total braking force corresponds to the signal of the brake value transmitter. Hereby, the friction brake with a short response time is fully effective, while with prolonged braking the retarder takes full braking power and protects the friction brake from overloading. On this basis, the present invention based on the problem to provide a novel method for operating a drive train.
Dieses Problem wird durch ein Verfahren gemäß Anspruch 1 gelöst. Erfindungsgemäß wird bei Anforderung eines Bremsmoments für den Abtrieb eines Hybridfahrzeugs das Bremsmoment zwischen der oder jeder elektrischen Maschine des Hybridantriebs und der oder jeder verschleißfreien Dauerbremse derart aufgeteilt, dass zu Beginn einer Bremsmomentanforderung das Bremsmoment ausschließlich von mindestens einer elektrischen Maschine des Hybridantriebs angefordert und am Abtrieb bereitgestellt wird, und dass darauffolgend abhängig von Kenngrößen der oder jeder verschleißfreien Dauerbremse die Bremsmomentanforderung zumindest teilweise von der oder jeder elektrischen Maschine an mindestens eine verschleißfreie Dauerbremse gesteuert übergeben wird, sodass das am Abtrieb von der oder jeder elektrischen Maschine und der oder jeder Dauerbremse bereitgestellte Bremsmoment in Summe dem angeforderten Bremsmoment entspricht. This problem is solved by a method according to claim 1. According to the invention, upon request of a braking torque for the output of a hybrid vehicle, the braking torque between the or each electric machine of the hybrid drive and the or each wear-free retarder split such that at the beginning of a braking torque request, the braking torque requested exclusively by at least one electric machine of the hybrid drive and provided at the output and, subsequently, depending on characteristics of the or each wear-free retarder, the brake torque request is at least partially transferred from the or each electric machine to at least one wear-free retarder such that the braking torque provided at the output by the or each electric machine and the or each retarder Sum corresponds to the requested braking torque.
Mit der hier vorliegenden Erfindung wird erstmals vorgeschlagen, eine Bremsmomentanforderung an einem Bremssystem eines Hybridfahrzeugs zwischen der oder jeder elektrischen Maschine des Hybridantriebs und der oder jeder verschleißfreien Dauerbremse des Bremssystems aufzuteilen, nämlich derart, dass zu Beginn einer Bremsanforderung das Bremsmoment ausschließlich von mindestens einer elektrischen Maschine des Hybridantriebs angefordert und am Abtrieb bereitgestellt wird. Erst darauffolgend wird abhängig von Kenngrößen der oder jeder verschleißfreien Dauerbremse die Bremsmomentanforderung zumindest teilweise von der oder jeder elektrischen Maschine an mindestens eine verschleißfreie Dauerbremse des Bremssystems gesteuert übergeben. Dies erfolgt derart, dass das am Abtrieb von der oder jeder elektrischen Maschine und der oder jeder Dauerbremse bereitgestellte Bremsmoment in Summe dem angeforderten Bremsmoment entspricht. Am Anfang einer Bremsmomentanforderung ist es demnach mit dem erfindungsgemäßen Verfahren möglich, über mindestens eine elektrische Maschine des Hybridantriebs unmittelbar mit hoher Dynamik und innerhalb kurzer Zeit am Abtrieb ein Bremsmoment bereit zu stellen und somit unmittelbar auf eine Bremsmomentanforderung zu reagieren. Darauffolgend wird die Bremsmomentanforderung gesteuert an der jeweiligen elektrischen Maschine des Hybridantriebs reduziert sowie gleichzeitig an mindestens einer verschleißfreien Dauerbremse des Bremssystems erhöht, um so gesteuert ein von der jeweiligen verschleißfreien Dauerbremse am Abtrieb bereitstellbares Bremsmoment aufzubauen. With the present invention, it is proposed for the first time to divide a brake torque requirement on a brake system of a hybrid vehicle between the or each electric machine of the hybrid drive and the or each wear-free retarder of the brake system, namely such that at the beginning of a braking request, the braking torque exclusively from at least one electric machine the hybrid drive is requested and provided at the output. Only then, depending on parameters of the or each wear-free retarder brake torque request is at least partially controlled by the or each electric machine controlled at least one wear-resistant retarder of the brake system. This is done such that the output provided by the or each electric machine and the or each retarder braking torque in total corresponds to the requested braking torque. At the beginning of a braking torque request, it is thus possible with the method according to the invention to provide at least one electric machine of the hybrid drive directly with high dynamics and within a short time at the output a braking torque ready and thus to respond directly to a braking torque request. Subsequently, the braking torque request is controlled reduced at the respective electric machine of the hybrid drive and at the same time increased at least one wear-free retarder of the brake system, so as to build a controlled from the respective wear-resistant retarder at the output braking torque.
Dabei wird um den Betrag, um den gesteuert von der jeweiligen ver- schleißfreien Dauerbremse am Abtrieb Bremsmoment aufgebaut wird, das von der oder jeder elektrischen Maschine am Abtrieb bereitgestellte Bremsmoment reduziert. In this case, the braking torque which is controlled by the respective wear-free retarder at the output is reduced by the braking torque provided by the or each electric machine at the output.
Dadurch ist es letztendlich möglich, zu Beginn einer Bremsmomentanforderung einerseits mit hoher Dynamik sowie innerhalb einer kurzen Reaktionszeit ein gewünschtes Bremsmoment am Abtrieb bereitzustellen und andererseits die jeweilige verschleißfreie Dauerbremse kontrolliert und gesteuert zum Aufbau des Bremsmoments zu nutzen. As a result, it is ultimately possible to provide a desired braking torque at the output on the one hand with high dynamics and within a short reaction time at the beginning of a braking torque request and, on the other hand, to use the respective wear-free retarded brake to build up the braking torque.
Darauffolgend erfolgt mit sich zunehmend verringernder Abtriebsdrehzahl eine Übergabe der Bremsmomentanforderung von der oder jeder ver- schleißfreien Dauerbremse zurück auf mindestens eine elektrische Maschine des Hybridantriebs, und zwar wiederum gesteuert, sodass das am Abtrieb von der oder jeder elektrischen Maschine und der oder jeder verschleißfreien Dauerbremse bereitgestellte Bremsmoment in Summe dem gewünschten bzw. angeforderten Bremsmoment entspricht. Hierdurch ist es möglich, dann, wenn in Folge einer sich zunehmend verringernden Abtriebsdrehzahl die jeweilige verschleißfreie Dauerbremse kein ausreichendes Bremsmoment mehr am Abtrieb bereitstellen kann, die jeweilige verschleißfreie Dauerbremse kontrolliert aus der Bremsmomentanforderung herauszunehmen, um so unterstützt durch mindestens eine elektrische Maschine des Hybridantriebs das von der jeweiligen verschleißfreien Dauerbremse nicht mehr bereitstellbare Bremsmoment auszugleichen. Subsequently, as the output speed decreases, the brake torque request from the or each wear-free retarder is transferred back to at least one hybrid drive electric machine, again controlled so that the output provided by the or each electric machine and the or each wear-free retarder Braking torque in total corresponds to the desired or requested braking torque. This makes it possible, then, as a result of an increasingly decreasing output speed, the respective wear-free retarder no longer can provide sufficient braking torque on the output, the respective wear-free retarder controlled remove from the braking torque request, so supported by at least one electric machine of the hybrid drive that of compensate for the respective wear-free retarder brake no longer deployable braking torque.
Bevorzugte Weiterbildungen der Erfindung ergeben sich aus den Unteransprüchen und der nachfolgenden Beschreibung. Ausführungsbeispiele der Erfindung werden, ohne hierauf beschränkt zu sein, an Hand der Zeichnung näher erläutert. Dabei zeigt: Preferred embodiments of the invention will become apparent from the dependent claims and the description below. Embodiments of the invention will be described, without being limited thereto, with reference to the drawings. Showing:
Fig. 1 ein Blockschaltbild eines exemplarischen Antriebsstrangs zur 1 is a block diagram of an exemplary powertrain for
Verdeutlichung des erfindungsgemäßen Verfahrens;  Clarification of the method according to the invention;
Fig. 2 ein erstes Diagramm zur weiteren Verdeutlichung des erfindungsgemäßen Verfahrens;  FIG. 2 shows a first diagram for further clarification of the method according to the invention; FIG.
Fig. 3 ein zweites Diagramm zur weiteren Verdeutlichung des erfindungsgemäßen Verfahrens; und  3 shows a second diagram for further clarification of the method according to the invention; and
Fig. 4 ein drittes Diagramm zur weiteren Verdeutlichung des erfindungsgemäßen Verfahrens.  Fig. 4 is a third diagram for further clarification of the method according to the invention.
Fig. 1 zeigt exemplarisch ein Antriebsstrangsschema eines Antriebsstrangs eines Hybridfahrzeugs, bei welchem das erfindungsgemäße Verfahren einsetzbar ist. So verfügt der Antriebsstrang der Fig. 1 über einen Verbrennungsmotor 1 und eine elektrische Maschine 2, die zusammen einen Hybridantrieb 3 des Antriebsstrangs bildet. Zwischen den Hybridantrieb 3, nämlich die elektrische Maschine 2 desselben, und einen Abtrieb 4 sind gemäß Fig. 1 sowohl ein Getriebe 5 als auch ein Retarder 6 geschaltet, wobei es sich beim Retarder 6 um eine verschleißfreie Dauerbremse handelt. Gemäß Fig. 1 ist der Retarder 6 zwischen die elektrische Maschine 2 des Hybridantriebs 3 und das Getriebe 5 geschaltet. Im Unterschied hierzu ist es auch möglich, dass der Retarder 6 zwischen den Getriebe 5 und den Abtrieb 4 oder zwischen den Verbrennungsmotor 1 und die elektrische Maschine 2 geschaltet ist. 1 shows by way of example a drive train diagram of a drive train of a hybrid vehicle in which the method according to the invention can be used. Thus, the drive train of FIG. 1 has an internal combustion engine 1 and an electric machine 2, which together form a hybrid drive 3 of the drive train. Between the hybrid drive 3, namely the electric machine 2 thereof, and an output 4, both a transmission 5 and a retarder 6 are connected according to FIG. 1, whereby the retarder 6 is a wear-resistant retarder. According to FIG. 1, the retarder 6 is connected between the electric machine 2 of the hybrid drive 3 and the transmission 5. In contrast, it is also possible that the retarder 6 is connected between the transmission 5 and the output 4 or between the internal combustion engine 1 and the electric machine 2.
Bereits an dieser Stelle sei darauf hingewiesen, dass das erfindungsgemäße Verfahren nicht auf die Anwendung an dem in Fig. 1 gezeigten Antriebsstrang beschränkt ist. Vielmehr kann die Erfindung an anderen Antriebssträngen von Hybridfahrzeugen zum Einsatz kommen, zum Beispiel dann, wenn Verbrennungsmotor und elektrische Maschine des Hybridantriebs auf unterschiedliche Achsen des Abtriebs des Hybridfahrzeugs wirken. It should already be noted at this point that the method according to the invention is not restricted to the application on the drive train shown in FIG. Rather, the invention can be used on other powertrains of hybrid vehicles, for example, when the internal combustion engine and electric machine of the hybrid drive act on different axes of the output of the hybrid vehicle.
Ein Antriebsstrang eines Hybridantriebs umfasst ein Bremssystem, über welches am Abtrieb 4 ein Bremsmoment bereitgestellt werden kann. So umfasst ein Bremssystem des Hybridfahrzeugs eine Betriebsbremse, die über Reibung auf Räder des Abtriebs 4 einwirkt. A drive train of a hybrid drive comprises a brake system, via which a braking torque can be provided at the output 4. Thus, a brake system of the hybrid vehicle comprises a service brake, which acts on the wheels of the output 4 via friction.
Neben einer solchen Betriebsbremse umfasst das Bremssystem eines Hybridfahrzeugs mindestens eine verschleißfreie Dauerbremse, wobei es sich bei dieser verschleißfreien Dauerbremse zum Beispiel um den in Fig. 1 gezeigten Retarder 6 handeln kann. Eine weitere verschleißfreie Dauerbremse eiens Bremssystems eines Hybridfahrzeugs wird von einer sogenannten Motorbremse des Verbrennungsmotors 1 bereitgestellt. In addition to such a service brake, the brake system of a hybrid vehicle comprises at least one wear-free retarder, wherein this wear-free retarder can be, for example, the retarder 6 shown in FIG. Another wear-free retarder of a brake system of a hybrid vehicle is provided by a so-called engine brake of the internal combustion engine 1.
Im Sinne der hier vorliegenden Erfindung wird vorgeschlagen, dass dann, wenn für den Abtrieb 4 ein Bremsmoment angefordert wird, das angeforderte Bremsmoment zumindest zwischen der oder jeder elektrischen Maschine 2 des Hybridantriebs 3 und der oder jeder verschleißfreien Dauerbremse aufgeteilt wird. Diese Aufteilung des angeforderten Bremsmoments erfolgt derart, dass zu Beginn einer Bremsmomentanforderung das Bremsmoment ausschließlich von mindestens einer elektrischen Maschine 2 des Hybridantriebs 3 angefordert und am Abtrieb 4 bereitgestellt wird, und dass darauffolgend abhängig von Kenngrößen der oder jeder verschleißfreien Dauerbremse die Bremsmomentanforderung von der oder jeder elektrischen Maschine 2 des Hybridantriebs 3 an mindestens eine verschleißfreie Dauerbremse 6 gesteuert übergeben wird, sodass das am Abtrieb 4 von der oder jeder elektrischen Maschine 2 des Hybridantriebs 3 und der oder jeder Dauerbremse bereitgestellte Bremsmoment in Summe dem angeforderten Bremsmoment entspricht. For the purposes of the present invention, it is proposed that if a braking torque is requested for the output 4, the requested braking torque is divided at least between the or each electric machine 2 of the hybrid drive 3 and the or each wear-free retarder. This division of the requested braking torque is such that at the beginning of a braking torque request, the braking torque is requested exclusively by at least one electric machine 2 of the hybrid drive 3 and provided at the output 4, and that subsequently depending on characteristics of the or each wear-free retarder the braking torque request of the or each electric machine 2 of the hybrid drive 3 is passed controlled at least one wear-free retarder 6, so that the output provided by the or each electric machine 2 of the hybrid drive 3 and the or each retarder braking torque in total corresponds to the requested braking torque.
Diesbezügliche Details werden nachfolgend unter Bezugnahme auf Fig. 2 beschrieben, wobei in Fig. 2 über der Zeit t mehrere zeitliche Kurvenverläufe gezeigt sind, nämlich ein zeitlicher Kurvenverlauf einer Drehzahl nAB des Abtriebs 4 des Antriebsstrangs, ein zeitlicher Kurvenverlauf MB eines mit einer Bremsmomentanforderung angeforderten Bremsmoments, ein zeitlicher Kurvenverlauf MR eines vom Retarder 6 am Abtrieb 4 bereitgestellten Bremsmoment sowie ein zeitlicher Kurvenverlauf MEM eines von der elektrischen Maschine 2 am Abtrieb 4 bereitgestellten Bremsmoments. Details relating to this are described below with reference to FIG. 2, FIG. 2 showing a plurality of time curves over the time t, namely a time curve of a rotational speed n A B of the output 4 of the drive train, a time curve M B of one having a Braking torque request requested braking torque, a time curve M R of the retarder 6 at the output 4 provided braking torque and a time curve M E M one of the electric machine 2 at the output 4 provided braking torque.
Beginnend mit dem Zeitpunkt t1 liegt in Fig. 2 eine Bremsmomentanforderung MB für ein am Abtrieb 4 bereitzustellendes Bremsmoment an. Erfindungsgemäß wird zu Beginn dieser Bremsmomentanforderung, also unmittelbar anschließend an den Zeitpunkt t1 , diese Bremsmomentanforderung ausschließlich von der elektrischen Maschine 2 angefordert, sodass zu Beginn der Bremsmomentanforderung, also unmittelbar anschließend an den Zeitpunkt t1 , das angeforderte Bremsmoment MB ausschließlich über das von der elektrischen Maschine 2 bereitstellbare Bremsmoment MEM am Abtrieb 4 bereitgestellt wird. Erst darauffolgend, nämlich in Fig. 2 beginnend mit dem Zeitpunkt t2, wird abhängig von Kenngrößen des Retarders 6 die Bremsmomentanforderung MB von der elektrischen Maschine 2 an den Retarder 6 kontinuierlich und gesteuert zumindest teilweise übergeben, und zwar derart, dass das am Abtrieb 4 von der elektrischen Maschine 2 bereitgestellte Bremsmoment MEM und das vom Retarder 6 am Abtrieb 4 bereitgestellte Bremsmoment MR in Summe dem angeforderten Bremsmoment MB entspricht. Starting with the time t1 is in Fig. 2, a braking torque request M B for a to be provided on the output 4 braking torque. According to the invention, at the beginning of this braking torque request, ie immediately after the time t1, this braking torque request is requested exclusively by the electric machine 2, so that at the beginning of the braking torque request, ie immediately after the time t1, the requested braking torque M B exclusively via that of the electric Machine 2 providable braking torque M E M is provided at the output 4. Only subsequently, namely in Fig. 2 starting at the time t2, depending on characteristics of the retarder 6, the braking torque request M B from the electric machine 2 to the retarder 6 continuously and controlled at least partially passed, in such a way that the output of the fourth provided by the electric machine 2 braking torque M E M and provided by the retarder 6 at the output 4 braking torque M R in total the requested braking torque M B corresponds.
In Fig. 2 bleibt das angeforderte Bremsmoment MB konstant, sodass Maschine 2 und Retarder 6 in Summe ein in etwa konstantes Bremsmoment am Abtrieb 4 bereitstellen. In Fig. 2, the requested braking torque M B remains constant, so that machine 2 and retarder 6 in total provide an approximately constant braking torque at the output 4.
Die teilweise Übergabe der Bremsmomentanforderung von der elektrischen Maschine 2 des Hybridantriebs 3 an den Retarder 6 bzw. die verschleißfreie Dauerbremse erfolgt in Fig. 2 zwischen den Zeitpunkten t2 und t3 jeweils rampenartig bzw. linear, d.h., dass zwischen den Zeitpunkten t2 und t3 einerseits die Bremsmomentanforderung von der elektrischen Maschine 2 des Hybridantriebs 3 rampenartig reduziert und die Bremsmomentanforderung von der verschleißfreien Dauerbremse, nämlich vom Retarder 6, rampenartig erhöht wird, und so auch die von denselben am Abtrieb 4 bereitgestellten Bremsmomente MEM bzw. MR. The partial transfer of the braking torque request from the electric machine 2 of the hybrid drive 3 to the retarder 6 and the wear-free retarder occurs in Fig. 2 between the times t2 and t3 respectively ramped or linear, ie, that between the times t2 and t3 on the one hand the Braking torque required by the electric machine 2 of the hybrid drive 3 ramp-reduced and the braking torque request of the wear-free retarder, namely the retarder 6, is ramped, and so also provided by the same at the output 4 braking torque M E M and MR.
Diese Übergabe der Bremsmomentanforderung erfolgt, wie bereits ausgeführt, abhängig von Kenngrößen des Retarders 6, wobei diese Übergabe vor der eigentlichen Bremsmomentanforderung und damit offline abhängig von den Kenngrößen des Retarders 6 ermittelt wird, sodass die Übergabe der Bremsmomentanforderung zwischen den Zeitpunkten t2 und t3 im Sinne einer vorgesteuerten Übergabe der Bremsmomentanforderung bzw. im Sinne einer Vorsteuerung ausgeführt wird. Fig. 3 zeigt eine Weiterbildung des erfindungsgemäßen Verfahrens für den Fall, dass sich die Abtriebsdrehzahl nAB zunehmend verringert. So kann Fig. 3 entnommen werden, dass dann, wenn sich die Abtriebsdrehzahl nAB am Abtrieb 4 und damit die Fahrgeschwindigkeit des Hybridfahrzeugs zunehmend verringert, nachfolgend wiederum eine Übergabe der Bremsmomentanforderung vom Retarder 6 auf die elektrische Maschine 2 des Hybridantriebs 3 erfolgt, nämlich gemäß Fig. 3 zwischen den Zeitpunkten t4 und t5. This transfer of the braking torque request takes place, as already stated, depending on parameters of the retarder 6, this transfer is determined before the actual braking torque request and thus offline depending on the characteristics of the retarder 6, so that the transfer of the braking torque request between the times t2 and t3 in the sense a pre-controlled transfer of the braking torque request or in the sense of pre-control is performed. FIG. 3 shows a development of the method according to the invention for the case in which the output rotational speed n A B is progressively reduced. Thus, Fig. 3 it can be seen that when the output speed n A B at the output 4 and thus the driving speed of the hybrid vehicle increasingly decreases, subsequently again a transfer of braking torque request from the retarder 6 takes place on the electric machine 2 of the hybrid drive 3, namely according to FIG. 3 between the times t4 and t5.
Dieser Weiterbildung des erfindungsgemäßen Verfahrens liegt die Erkenntnis zugrunde, dass der Retarder 6 ab Unterschreiten einer Mindestdrehzahl kein Bremsmoment mehr am Abtrieb 4 bereitstellen kann. Rechtzeitig bevor diese Mindestdrehzahl unterschritten wird, wird erfindungsgemäß die Bremsmomentanforderung am Retarder 6 kontinuierlich, vorzugsweise rampenartig, und damit gesteuert reduziert und entsprechend an der elektrischen Maschine 2 des Hybridantriebs 3 kontinuierlich, vorzugsweise rampenartig, und gesteuert erhöht, sodass das von dem Retarder 6 und der elektrischen Maschine 2 in Summe am Abtrieb 4 bereitgestellte Bremsmoment wiederum dem angeforderten Bremsmoment MB entspricht. This refinement of the method according to the invention is based on the finding that the retarder 6 can no longer provide any braking torque at the output 4 when it falls below a minimum rotational speed. In good time before this minimum speed is exceeded, according to the invention, the brake torque request on the retarder 6 continuously, preferably ramp-like, and thus controlled reduced and accordingly on the electric machine 2 of the hybrid drive 3 continuously, preferably ramp-like, and controlled increases, so that of the retarder 6 and the electric machine 2 in total at the output 4 provided braking torque in turn corresponds to the requested braking torque M B.
Der Zeitpunkt t4, ab welchem mit zunehmender Verringerung der Abtriebsdrehzahl nAB die Bremsmomentanforderung von dem Retarder 6 zurück auf die elektrische Maschine 2 übertragen wird, kann abhängig von Kenngrößen des Retarders 6 vorab offline ermittelt werden. Vorzugsweise wird jedoch so vorgegangen, dass während der Bremsmomentanforderung und damit während der Ausführung der Bremsung die aktuelle Abtriebsdrehzahl nAB am Abtrieb 4 überwacht wird und abhängig hiervon im Sinne einer steuerungstechnischen Beobachtung der Zeitpunkt t4, ab welchem die Momentübergabe vom Retarder 6 auf die elektrische Maschine 2 beginnt, während der Ausführung der Bremsmomentanforderung online ermittelt wird. Ab dem Zeitpunkt t5, ab welchem der Retarder 6 am Abtrieb 4 kein Bremsmoment MR mehr bereitstellen kann, stellt ausschließlich die elektrische Maschine 2 ein entsprechendes Bremsmoment MEM am Abtrieb 4 bereit. The point in time t4, from which the braking torque request is transmitted from the retarder 6 back to the electric machine 2 with increasing reduction of the output rotational speed n A B, can be determined in advance in advance depending on parameters of the retarder 6. Preferably, however, the procedure is such that during the braking torque request and thus during the execution of the braking the current output speed n A B is monitored at the output 4 and dependent thereof in terms of a control observation of the time t4, from which the torque transfer from the retarder 6 to the electric Machine 2 begins to be determined online while the brake torque request is being executed. From the time t5, from which the retarder 6 can no longer provide braking torque M R at the output 4, only the electric machine 2 provides a corresponding braking torque M E M at the output 4.
Dann, wenn zum Zeitpunkt t6 das Hybridfahrzeug stillsteht, wird zum Schutz der elektrischen Maschine 2 des Hybridantriebs das von derselben bereitgestellte Bremsmoment MEM auf Null reduziert und anschließend das angeforderte Bremsmoment von einer Betriebsbremse des Bremssystems, die insbesondere über Reibung auf die Räder des Abtriebs 4 einwirkt, bereitgestellt. Then, when the hybrid vehicle is stationary at time t6, to protect the electric machine 2 of the hybrid drive, the braking torque M E M provided by the same is reduced to zero and then the requested braking torque of a service brake of the brake system, in particular via friction on the wheels of the output 4 acts, provided.
Fig. 4 zeigt eine Variante der Erfindung, in welcher eine Bremsmomentanforderung zwischen der elektrischen Maschine 2 eines Hybridantriebs und zwei verschleißfreien Teilbremsen des Bremssystems des Hybridfahrzeugs aufgeteilt wird, nämlich zwischen einer Motorbremse und einem Retarder. 4 shows a variant of the invention in which a braking torque request is divided between the electric machine 2 of a hybrid drive and two wear-free partial brakes of the braking system of the hybrid vehicle, namely between an engine brake and a retarder.
So zeigt Fig. 4 über der Drehzahl nAB des Abtriebs 4 eines Hybridfahrzeugs Momentverläufe, nämlich den drehzahlabhängigen Verlauf eines angeforderten Bremsmoments MB, den drehzahlabhängigen Verlauf eines von der elektrischen Maschine 2 des Hybridantriebs am Abtrieb 4 bereitgestellten Bremsmoments MEM, den drehzahlabhängigen Verlauf eines von einer Motorbremse am Abtrieb 4 bereitgestellten Bremsmoments MMB, sowie den drehzahlabhängigen Momentverlauf eines vom Retarder am Abtrieb 4 bereitgestellten Bremsmoments MR. So kann Fig. 4 entnommen werden, dass einerseits zwischen der elektrischen Maschine 2 und der Motorbremse und andererseits zwischen der elektrischen Maschine 2 und dem Retarder 6 eine erfindungsgemäße, gesteuerte Übergabe der Bremsmomentanforderung erfolgt, sodass das von den Teilbremssystemen in Summe am Abtrieb 4 bereitgestellte Bremsmoment dem angeforderten Bremsmoment MB entspricht. Es liegt demnach im Sinne der hier vorliegenden Erfindung, bei einem Antriebsstrang eines Hybridfahrzeugs ein von einem Bremssystem angefordertes Bremsmoment zwischen einer elektrischen Maschine 2 des Hybridantriebs 3 des Hybridfahrzeugs und mindestens einer verschleißfreien Dauerbremse des Hybridfahrzeugs, nämlich zwischen einem Retarder und/oder einer Motorbremse, steuerungsseitig aufzuteilen. Thus, Fig. 4 shows the rotational speed n A B of the output 4 of a hybrid vehicle torque curves, namely the speed-dependent curve of a requested braking torque MB, the speed-dependent course of a provided by the electric machine 2 of the hybrid drive at the output 4 braking torque M E M, the speed-dependent curve one of an engine brake on the output 4 provided braking torque M M B, and the speed-dependent torque curve of the retarder at the output 4 provided braking torque M R. Thus, Fig. 4 can be seen that on the one hand between the electric machine 2 and the engine brake and on the other hand between the electric machine 2 and the retarder 6 according to the invention, a controlled transfer of braking torque request takes place, so that provided by the partial braking systems in total at the output 4 braking torque corresponds to the requested braking torque M B. It is therefore within the meaning of the present invention, in a drive train of a hybrid vehicle requested by a brake system braking torque between an electric machine 2 of the hybrid drive 3 of the hybrid vehicle and at least one wear-free retarder of the hybrid vehicle, namely between a retarder and / or an engine brake, the control side divide.
Über das dynamische Verhalten der elektrischen Maschine 2 des Hybridantriebs 3, die zur Bereitstellung eines Bremsmoments generatorisch betrieben wird, kann die fehlende Dynamik des Retarders bzw. der Motorbremse kompensiert werden. Zu Beginn einer Bremsmomentanforderung wird daher zunächst über mindestens eine elektrische Maschine 2 des Hybridantriebs 3 das angeforderte Bremsmoment am Abtrieb 4 bereitgestellt. Anschließend wird über die verschleißfreie Dauerbremse, insbesondere über einen Retarder oder gegebenenfalls eine Motorbremse, gesteuert Bremsmoment am Abtrieb aufgebaut. Dann, wenn der Retarder bzw. die Motorbremse abhängig von der Abtriebsdrehzahl des Abtriebs kein Bremsmoment mehr bereitstellen kann, wird der Retarder bzw. die Motorbremse gesteuert aus dem Bremseingriff am Abtrieb 4 herausgefahren, während dann die oder jede elektrische Maschine 2 des Hybridantriebs 3 im generatorischen Betrieb die an der jeweiligen ver- schleißfreien Dauerbremse reduzierte Bremsmomentanforderung übernimmt und das entsprechende Bremsmoment am Abtrieb bereitstellt. About the dynamic behavior of the electric machine 2 of the hybrid drive 3, which is operated as a generator for providing a braking torque, the lack of dynamics of the retarder and the engine brake can be compensated. At the beginning of a braking torque request, therefore, the requested braking torque is initially provided at the output 4 via at least one electric machine 2 of the hybrid drive 3. Subsequently, brake torque is developed at the output via the wear-free retarder, in particular via a retarder or optionally an engine brake. Then, if the retarder or the engine brake depending on the output speed of the output can no longer provide braking torque, the retarder or the engine brake is driven out of the braking intervention on the output 4, while then the or each electric machine 2 of the hybrid drive 3 in the regenerative Operation assumes the reduced braking torque request at the respective wear-free retarder and provides the corresponding braking torque at the output.
Mithilfe der hier vorliegenden Erfindung ist es möglich, während einer gesamten Bremsmomentanforderung, ohne die Gefahr eines Überbremsens und ohne die Gefahr von Schwingungen im Antriebsstrang sowohl zu Beginn einer Bremsmomentanforderung als auch mit zunehmender Verringerung der Abtriebsdrehzahl am Ende der Bremsmomentanforderung das gewünschte Bremsmoment für den Abtrieb 4 zuverlässig bereitzustellen. Bezuqszeichen Verbrennungsmotor By means of the present invention, it is possible, without the risk of overbraking and without the risk of vibrations in the drive train both at the beginning of a braking torque request and with increasing reduction of the output speed at the end of the braking torque request, the desired braking torque for the output. 4 to provide reliable. Designation internal combustion engine
elektrische Maschine electric machine
Hybridantrieb hybrid drive
Abtrieb output
Getriebe transmission
Retarder retarder

Claims

Patentansprüche claims
1 . Verfahren zum Betreiben eines Antriebsstrangs eines Kraftfahrzeugs mit einem mindestens eine elektrische Maschine und einen Verbrennungsmotor umfassenden, als Hybridantrieb ausgebildeten Antriebsaggregat, mit einem Getriebe, mit einem Abtrieb und mit einem Bremssystem, welches mindestens eine verschleißfreie Dauerbremse umfasst, dadurch gekennzeichnet, dass bei Anforderung eines Bremsmoments für den Abtrieb das Bremsmoment zwischen der oder jeder elektrischen Maschine des Hybridantriebs und der oder jeder verschleißfreien Dauerbremse derart aufgeteilt wird, dass zu Beginn einer Bremsmomentanforderung das Bremsmoment ausschließlich von mindestens einer elektrischen Maschine des Hybridantriebs angefordert und am Abtrieb bereitgestellt wird, und dass darauffolgend abhängig von Kenngrößen der oder jeder verschleißfreien Dauerbremse die Bremsmomentanforderung zumindest teilweise von der oder jeder elektrischen Maschine an mindestens eine ver- schleißfreie Dauerbremse gesteuert übergeben wird, sodass das am Abtrieb von der oder jeder elektrischen Maschine und der oder jeder Dauerbremse bereitgestellte Bremsmoment in Summe dem angeforderten Bremsmoment entspricht. 1 . A method for operating a drive train of a motor vehicle with a comprehensive at least one electric machine and an internal combustion engine, designed as a hybrid drive unit, with a transmission, with an output and with a braking system, which comprises at least one wear-free retarder, characterized in that upon request of a braking torque for the output, the braking torque between the or each electric machine of the hybrid drive and the or each wear-free retarder is divided such that at the beginning of a braking torque request, the braking torque is requested exclusively by at least one electric machine of the hybrid drive and provided at the output, and that depending on Characteristics of the or each wear-free retarder the braking torque request at least partially controlled by the or each electric machine to at least one wear-free retarder practice will give, so that the output provided by the or each electric machine and the or each retarder braking torque in total corresponds to the requested braking torque.
2. Verfahren nach Anspruch 1 , dadurch gekennzeichnet, dass die Bremsmomentanforderung von der oder jeder elektrischen Maschine des Hyb- risantriebs an mindestens eine verschleißfreie Dauerbremse derart gesteuert übergeben wird, dass die Bremsmomentanforderung von der oder jeder elektrischen Maschine des Hybridantriebs kontinuierlich, insbesondere rampenartig, reduziert und die Bremsmomentanforderung von der oder jeder verschleißfreien Dauerbremse kontinuierlich, insbesondere rampenartig, erhöht wird, wobei diese kontinuierliche, insbesondere rampenartige, Übergabe der Bremsmomentanforderung abhängig von Kenngrößen der oder jeder verschleißfreien Dauerbremse vorab ermittelt und so im Sinne einer vorgesteuerten Übergabe der Bremsmomentanforderung ausgeführt wird. 2. The method according to claim 1, characterized in that the braking torque request from the or each electric machine of the Hyb- risantriebs passed to at least one wear-free retarder such controlled that the braking torque demand of the or each electric machine of the hybrid drive continuously, in particular ramp-like reduced and the braking torque requirement of the or each wear-free retarder continuously, in particular ramp-like, is increased, this continuous, in particular ramp-like, transfer of braking torque request depending on characteristics of the or each wear-free retarder is determined in advance and executed in the sense of a precontrolled transfer of braking torque request.
3. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass darauffolgend mit sich zunehmend verringernder Abtriebsdrehzahl die Bremsmomentanforderung von der oder jeder verschleißfreien Dauerbremse wieder an mindestens eine elektrische Maschine des Hybridantriebs gesteuert übergeben wird, sodass das am Abtrieb von der oder jeder elektrischen Maschine des Hybridantriebs und der oder jeder Dauerbremse bereitgestellte Bremsmoment in Summe dem angeforderten Bremsmoment entspricht. 3. The method of claim 1 or 2, characterized in that subsequently passed with increasing decreasing output speed, the braking torque demand of the or each wear-free retarder is controlled back to at least one electric machine of the hybrid drive, so that at the output of the or each electric machine of the Hybrid drive and the or each retarder brake torque provided in total corresponds to the requested braking torque.
4. Verfahren nach Anspruch 3, dadurch gekennzeichnet, dass die Bremsmomentanforderung von der oder jeder verschlei ßfreien Dauerbremse an mindestens eine elektrischen Maschine des Hybridantriebs derart gesteuert übergeben wird, dass die Bremsmomentanforderung von der oder jeder ver- schleißfreien Dauerbremse kontinuierlich, insbesondere rampenartig, reduziert und die Bremsmomentanforderung von der oder jeder elektrischen Maschine des Hybridantriebs kontinuierlich, insbesondere rampenartig, erhöht wird, wobei diese kontinuierliche, insbesondere rampenartige, Übergabe während der Bremsmomentanforderung abhängig von der aktuellen Abtriebsdrehzahl ermittelt wird. 4. The method according to claim 3, characterized in that the braking torque request of the or each verschle ßfreien retarder is passed to at least one electric machine of the hybrid drive controlled such that the braking torque demand of the or each wear-free retarder continuously, in particular ramp-like reduced and the braking torque requirement of the or each electric machine of the hybrid drive continuously, in particular ramp-like, is increased, said continuous, in particular ramp-like, transfer during the braking torque request is determined depending on the current output speed.
5. Verfahren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass dann, wenn die Abtriebsdrehzahl bis zum Stillstand des Kraftfahrzeugs verringet wird, das Bremsmoment ausschließlich von einer Betriebsbremse des Bremssystems angefordert und am Abtrieb des Antriebsstrangs bereitgestellt wird. 5. The method according to any one of claims 1 to 4, characterized in that when the output speed is reduced to a standstill of the motor vehicle, the braking torque is requested exclusively by a service brake of the brake system and provided at the output of the drive train.
6. Verfahren nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass auf diese Art und Weise Bremsmoment von einer elektrischen Maschine des Hybridantriebs und einer als Retarder ausgebildeten, verschleißfreien Dauerbremse angefordert und am Abtrieb bereitgestellt wird. 6. The method according to any one of claims 1 to 5, characterized in that requested in this manner braking torque from an electric machine of the hybrid drive and designed as a retarder, wear-resistant retarder and provided on the output.
7. Verfahren nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass auf diese Art und Weise Bremsmoment von einer elektrischen Maschine des Hybridantriebs und einer als Motorbremse ausgebildeten, ver- schleißfreien Dauerbremse angefordert und am Abtrieb bereitgestellt wird. 7. The method according to any one of claims 1 to 5, characterized in that in this way braking torque is requested by an electric machine of the hybrid drive and designed as an engine brake, wear-free retarder and provided on the output.
8. Verfahren nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass auf diese Art und Weise Bremsmoment von einer elektrischen Maschine des Hybridantriebs, einer als Motorbremse ausgebildeten, ersten ver- schleißfreien Dauerbremse und einer als Retarder ausgebildeten, zweiten ver- schleißfreien Dauerbremse angefordert und am Abtrieb bereitgestellt wird. 8. The method according to any one of claims 1 to 5, characterized in that requested in this manner braking torque from an electric machine of the hybrid drive, designed as an engine brake, the first wear-free retarder and trained as a retarder, second wear-free retarder and provided at the output.
EP11711894.3A 2010-05-27 2011-04-04 Method for operating a drive train Withdrawn EP2576306A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102010029386A DE102010029386A1 (en) 2010-05-27 2010-05-27 Method for operating a drive train
PCT/EP2011/055164 WO2011147616A1 (en) 2010-05-27 2011-04-04 Method for operating a drive train

Publications (1)

Publication Number Publication Date
EP2576306A1 true EP2576306A1 (en) 2013-04-10

Family

ID=44118894

Family Applications (1)

Application Number Title Priority Date Filing Date
EP11711894.3A Withdrawn EP2576306A1 (en) 2010-05-27 2011-04-04 Method for operating a drive train

Country Status (5)

Country Link
US (1) US8690724B2 (en)
EP (1) EP2576306A1 (en)
CN (1) CN102917934B (en)
DE (1) DE102010029386A1 (en)
WO (1) WO2011147616A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3008369B1 (en) * 2013-07-12 2015-06-26 Renault Sa TORQUE CONTROL TRANSMITTED TO A POWER WHEEL OF A HYBRID MOTOR VEHICLE
SE541864C2 (en) * 2017-03-08 2020-01-02 Ka Group Ag System for an electrical drive comprising a hydraulic auxiliary brake system
US11685367B2 (en) * 2020-09-09 2023-06-27 Ford Global Technologies, Llc System and method for reducing vehicle turning radius
DE102021123805A1 (en) 2021-09-15 2023-03-16 Voith Patent Gmbh Method of braking a powertrain and vehicle

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4446485C2 (en) * 1994-12-23 2003-06-26 Daimler Chrysler Ag Method and device for braking a motor vehicle with hybrid drive
JPH11289610A (en) * 1998-04-01 1999-10-19 Nissan Motor Co Ltd Auxiliary brake for hybrid car
DE19843580A1 (en) 1998-09-23 2000-03-30 Zahnradfabrik Friedrichshafen Brake installation has upon operation of retarder, friction brake subjected to pressure corresponding first to signal of braking value transmitter
US7131708B2 (en) * 2004-05-14 2006-11-07 General Motors Corporation Coordinated regenerative and engine retard braking for a hybrid vehicle
AU2007292710B2 (en) * 2006-09-05 2010-05-13 Hitachi Construction Machinery Co., Ltd. Brake system of electrically driven dump truck
US20080174174A1 (en) * 2007-01-22 2008-07-24 James S. Burns Passive Truck Trailer Braking Regeneration and Propulsion System and Method
US7828693B2 (en) * 2007-06-20 2010-11-09 Ford Global Technologies, Llc Negative driveline torque control incorporating transmission state selection for a hybrid vehicle
EP2127987B1 (en) 2008-05-27 2013-07-03 IVECO S.p.A. Braking method and device with energy recovery in particular for a vehicle equipped with hybrid traction system
DE102008041760A1 (en) 2008-06-11 2009-12-17 Robert Bosch Gmbh Braking device for a motor vehicle
JP5411939B2 (en) * 2008-10-21 2014-02-12 ルノー・トラックス Method and system for determining the ability of a driver of a hybrid vehicle, and vehicle equipped with such a system
DE102009026432A1 (en) * 2009-05-25 2010-12-09 Zf Friedrichshafen Ag Method for operating a drive train

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2011147616A1 *

Also Published As

Publication number Publication date
DE102010029386A1 (en) 2011-12-01
US8690724B2 (en) 2014-04-08
CN102917934A (en) 2013-02-06
US20130065728A1 (en) 2013-03-14
CN102917934B (en) 2015-10-21
WO2011147616A1 (en) 2011-12-01

Similar Documents

Publication Publication Date Title
DE102013104315A1 (en) Controlled regenerative brake torque increase when downshifting hybrid vehicles
EP2504211B1 (en) Method and device for operating a hybrid vehicle
EP2349801A2 (en) Method and device for starting a hybrid vehicle
DE102010008726A1 (en) Method for operating a drive system for a motor vehicle
DE102005035303A1 (en) Motor vehicle`s start-up process controlling method, involves adjusting rotational speed and/or drive torque of drive motor to upper threshold value that is dependent on characteristic value of torque transmission unit
DE19807095B4 (en) Method for controlled braking intervention in an automatic circuit
DE102005021714A1 (en) Method and device for avoiding unwanted vehicle accelerations in deceleration systems on a gradient
DE102008020842A1 (en) Motor vehicle has control device and unit coupled with control device for switching between two operating modes of drive unit, where control device is coupled with brake pedal
DE102013113658B4 (en) Method for operating a drive train
WO2011147616A1 (en) Method for operating a drive train
EP2048053B1 (en) Method for controlling the mechanical drive train of a vehicle
EP3074258B1 (en) Devices and method for distributing a total target torque specification
EP2337715A1 (en) Method for operating a brake system in a vehicle
DE102013016762B4 (en) Method for operating a drive train for a four-wheel drive motor vehicle
DE102012220768A1 (en) Method for operating motor car i.e. hybrid car, involves activating sailing mode during active speed and/or longitudinal control when driver-side and/or vehicle-side are defined at permissible speed range for sailing mode
DE102016216356B4 (en) Method for controlling a vehicle drive for a motor vehicle and vehicle drive
DE102005004224A1 (en) Method for controlling the starting process in a drive train of a vehicle
DE102009038553A1 (en) Drive train i.e. hybrid-drive train such as parallel-hybrid-drive train, operating method for motor vehicle i.e. hybrid vehicle, involves changing partial torque provided for direct drive path to difference torque with reverse sign
EP3873763A1 (en) Method and drive control device for operating at least two electric drive machines in the event of a change in load and motor vehicle with a drive control device
WO2013189812A1 (en) Vehicle stabilization for a hybrid vehicle in the event of brake slip of the drive wheels or increased risk thereof
WO2015193094A2 (en) Controlling a clutch device for optimizing the recuperation of an electric motor
DE102009057989A1 (en) Drive system operating method for motor vehicle, involves switching transmission if no delay of vehicle occurs at maximum recuperation moment such that drive axle is connected with drive device by smaller translation of transmission
DE102012212282B4 (en) Method for braking a motor vehicle with a dual clutch transmission
WO2010037494A1 (en) System for controlling a regenerative drive and method for controlling a regenerative drive
DE102011005468A1 (en) Actuation method for hybrid vehicle drive train, involves determining torque produced by electric machine for functions i.e. driving operations, from difference of maximum actual torque produced by electric machine and starting torque

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20121002

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20161101