DE102020104047A1 - Transmission for a hybrid vehicle and method for operating such a transmission - Google Patents

Abstract

The invention relates to a transmission (1) for a hybrid vehicle (2) in order to transmit torque at least between an internal combustion engine (3), an electric motor (4) and a transmission output (5), comprising a planetary gear (6) in the torque flow, which can be switched from a control device (7) through several switching mechanisms (8a, 8b, 8c) into several operating modes (9a, 9b, 9c, 9d, 9e, 9f), one of which is an operating mode (9a, 9b, 9c, 9d, 9e, 9f) is a recuperation mode (9a) in which the internal combustion engine (3) acts as a driving force and the electric motor (4) is provided in generator mode to charge an operatively connected charge storage device (10), with at least a first battery protection threshold value (7) in the control device (7). 11) is stored, which reflects a state of charge (12) of the charge store (10), the control device (7) being set up to switch the switching mechanisms (8a, 8b, 8c) s when the first battery protection threshold (11) is undershot o to control that the drive of the hybrid vehicle (2) is forced by the internal combustion engine (3) so that the hybrid vehicle (2) is operated in recuperation mode (9a).

Description

The invention relates to a transmission for a hybrid vehicle in order to pass torque at least between an internal combustion engine, an electric motor and a transmission output, comprising a planetary gear located in the torque flow, which can be switched into several operating modes by a control device by several switching mechanisms, one of which is a recuperation mode is, in which the internal combustion engine acts as a driving force and the electric motor is provided in generator mode to charge an operatively connected charge storage device. In addition, the invention relates to a hybrid vehicle comprising such a transmission and a method for operating such a transmission.

In principle, there are already transmissions or transmission units that couple electrical operating modes at low vehicle speeds (EV modes) and types of combustion (ICE modes) at high vehicle speeds. Dedicated hybrid transmissions (DHT) are also enjoying increasing popularity.

In principle, two different transmission architectures are known from the prior art: For example, P2 parallel hybrids are known that work with an electrical machine located between the internal combustion engine and the transmission, with a separating clutch used to separate the internal combustion engine from the drive train . In this case, operation can take place in pure electric mode, with the electric machine delivering the torque to the transmission and not to the internal combustion engine. The advantage of this hybrid variant is that it is possible to use an existing transmission with an electric motor and a separating clutch to separate the internal combustion engine from the drive train.

On the other hand, serial, serial-parallel or power-split hybrids are known from the prior art, in which a generator driven by the internal combustion engine generates electricity that is used to drive an electric motor that drives the vehicle (series operation). These transmissions are also called power split transmissions. In most arrangements, however, part of the power of the internal combustion engine is transferred mechanically to the wheels (series parallel operation).

It's the patent publication EP 3 315 372 A1 known, which discloses a battery operation and management strategy for DHT transmissions (Dedicated Hybrid Transmission) for four ratios in combustion mode and two electrical ratios. With the transmission proposed here, the hybrid vehicle can only be started with the two electric gears.

From the prior art is that DE 10 2016 221 045 A1 known, which relates to a transmission arrangement for a hybrid vehicle, in which a connection for an internal combustion engine, a connection for an electrical machine and a transmission part of the transmission arrangement are arranged such that they can be coupled to one another. The gear part comprises a simple Ravigneaux planetary gear set with two planetary gears and a single ring gear. The transmission part also has two brakes and two clutches as frictional shifting elements. The publication also discloses a drive arrangement with such a transmission arrangement and in each case an internal combustion engine connected to it and a connected electrical machine. Also part of the DE 10 2016 221 045 A1 is a method for operating such a drive arrangement and a hybrid vehicle equipped with such a drive arrangement.

In summary, that seems DE 10 2016 221 045 A1 to disclose a concept with two planetary gear sets and four clutch devices in order to map up to four forward gears for the combustion engine, two gears for the electric motor, one gear of the electrically continuously variable transmission (EVT, Electrically Variable Transmission) and a mode for stationary charging.

Furthermore, from the prior art, the EP 2 146 855 B1 known that a hybrid drive system for a vehicle, comprising a torsional vibration damper arrangement with a primary side to be coupled to a drive shaft of a drive unit for common rotation about an axis of rotation and with a secondary side supported via a damper element arrangement with respect to the primary side for torque transmission and with respect to the primary side rotatable about the axis of rotation, a clutch arrangement with an input area, which is coupled or to be coupled to the secondary side for common rotation about the axis of rotation (A), and with an output area that can be coupled by frictional engagement with the input area for rotation, an electric machine, with a stator arrangement of the electric machine on a stationary assembly is carried or to be carried and a rotor assembly of the electric machine is coupled to the output region of the clutch assembly for common rotation about the axis of rotation, the input region of the clutch assembly is connected or connectable to the secondary side of the torsional vibration damper arrangement via a Hirth serration and / or a plug connection with relative axial displaceability, the coupling arrangement having a housing comprises and that a coupling-side part of the Hirth serration or the plug connection is formed on a housing hub area.

In addition, from the publication WO 2016/075336 a torque transmission device known, comprising: an input shaft, a first planetary gear set, which has as first gear elements at least one first planetary gear for meshing with a first sun gear and with a first ring gear of the first planetary gear set and a planet carrier for rotatably supporting at least one of the first planetary gears, a second Planetary gear set, which has as second gear elements at least one second planetary gear for meshing with a second sun gear and with a second ring gear of the second planetary gear set and for meshing with one of the first planetary gears, at least one of the second planetary gears being rotatably supported by the planet carrier, a first braking device, designed for releasably securing the second sun gear, and a second braking device designed for releasably securing at least one of the first transmission elements, a first separating clutch, designed ltet for rotary connection of the input shaft with at least one of the first transmission elements, and a second separating clutch, configured for rotary connection of the input shaft with another of the first transmission elements or with one of the second transmission elements, an output shaft which is rotationally connected with another of the second transmission elements, an electric machine , which is rotatably connected to one of the gear elements.

In addition, the DE 10 2018 130 498 A1 referenced, which discloses a gear unit for a hybrid motor vehicle, with a planetary gear, wherein the planetary gear is equipped with a first planetary gear set and a second planetary gear set, an electrical machine coupled to a component of the planetary gear and several, each forming a brake or a clutch and shifting devices adjustable between an activated position and a deactivated position, the shifting devices being used to shift different gear ratios between an input that can be coupled to an internal combustion engine and an output and / or between the electrical machine and the output, characterized in that no more than four Switching devices for converting at least two different gear ratios in a drive state of the internal combustion engine, at least one gear ratio in a drive state of the electric machine e and at least one gear ratio are present in a recuperation state of the electrical machine due to their activated and deactivated positions.

The disadvantage of the known prior art is that the battery is quickly discharged during repeated starts, for example in urban areas with a high volume of traffic. In the known prior art, the battery is charged in that the electric machine is driven by the internal combustion engine while the vehicle is at a standstill. Another disadvantage of the known prior art is that the charging phases are often insufficient to recharge the battery. In addition, the operation of the internal combustion engine at a standstill to charge the battery represents an acoustic impairment. Overall, therefore, both the limited operating times and the high level of noise generated from the known prior art are disadvantageous.

It is the object of the present invention to provide a more efficient, longer-lasting and quieter transmission. The disadvantages known from the prior art are also intended to be eliminated or at least reduced.

This object is achieved in a generic transmission according to the invention in that at least one first battery protection threshold value is stored in the control device, which represents a state of charge of the charge storage device, the control device being set up to control the switching mechanisms so that the drive of the hybrid vehicle is forced by the internal combustion engine, so that the hybrid vehicle is operated in recuperation mode.

In such an embodiment according to the invention, when the charge level of the battery of the hybrid vehicle is undershot, the switching mechanisms, that is to say the brakes and clutches of the transmission, are switched so that the vehicle is operated in combustion mode. In this case, the electric motor runs in generator mode and charges the charge storage device. The control device is thus designed in such a way that it controls the switching mechanisms in such a way that the internal combustion engine causes the charge store, that is to say the battery, to be charged when the predetermined battery protection threshold is not reached. In an advantageous manner, the impairment of noise when the vehicle is at a standstill is thus minimized and the charge storage device is always controlled in such a way that it is sufficiently charged.

In a particularly advantageous manner, the control device of the transmission is pre-set up in such a way that, when power is requested, over an extra performance threshold to control the switching mechanisms in such a way that the energy of the electric motor is used exclusively or in addition to drive the hybrid vehicle. In addition to the already available drive energy of the internal combustion engine, drive energy is provided by the electric motor when the driver requests additional drive energy that is above the preset or extra power threshold defined by the driver.

In a further advantageous manner, a strategic battery threshold value is also stored in the control device of the transmission, the control device being pre-set up to control the switching mechanisms if the strategic battery threshold value is not reached in such a way that the electric motor for driving the hybrid vehicle can only be operated n times . This ensures that there is always sufficient charge capacity in the battery to start the hybrid vehicle.

A preferred embodiment is that the value “n times” is determined by the control device as a function of the stored strategic battery threshold value and other framework conditions, such as downhill or uphill gradient on which the hybrid vehicle is standing. The transmission and / or the hybrid vehicle includes an incline sensor which is designed to determine the incline on which the vehicle is standing. A higher starting energy is required to start the vehicle on an incline. The strategic battery threshold value must therefore be set higher in this starting position than when starting on a slope. Another boundary condition that is taken into account is the outside temperature and the humidity of the environment.

In a further preferred embodiment, the control algorithm is designed so that above a desired additional power threshold, the switching mechanisms are activated by the control device in such a way that the electric motor is operated in a peak range, or the internal combustion engine is switched on to operate in a boost range to realize. By switching on the electric motor in combustion mode, the peak area is mapped which transfers the additional power reserve of the electric motor to the transmission output. In boost mode, the internal combustion engine is switched on while driving with the electric motor in order to use its power reserve. This is advantageous, for example, when driving quickly on an incline or when accelerating suddenly.

In a particularly preferred embodiment, a hybrid vehicle comprises an internal combustion engine, an electric motor and the transmission according to the invention in order to transfer torque at least between the internal combustion engine, the electric motor and the transmission output. The transmission is thus used particularly efficiently and its functions and operating modes can be used to the full.

• - Erfassen des Ladezustandes des Ladungsspeichers;
• - kontinuierliches Analysieren und Verarbeiten des erfassten Ladezustandes durch die Steuereinrichtung des Getriebes;
• - Ansteuern der jeweiligen Schaltmechanismen in Abhängigkeit des Ladezustandes, sobald dieser einen vordefinierten ersten Batterieschonschwellenwert unterschreitet, so dass der Antrieb des Hybridfahrzeuges durch den Verbrennungsmotor über die Schaltmechanismen erzwungen wird. Der Ladezustand wird über entsprechende Ladezustandssensoren direkt an dem Ladungsspeicher gemessen und an die Steuereinrichtung übertragen, die den Ladezustand kontinuierlich analysiert und verarbeitet. Sobald die Analyse des aktuellen Ladezustandes ergibt, dass dieser unter einen vordefinierten ersten Batterieschonschwellenwert sinkt, steuert die Steuereinrichtung die Schaltmechanismen an, so dass der Antrieb des Hybridfahrzeuges über den Verbrennungsmotor erzwungen wird. Dabei wird der Elektromotor im Generatorbetrieb betrieben und lädt den Ladungsspeicher auf, so dass der Ladungszustand des Ladungsspeichers wieder über den ersten Batterieschonschwellenwert steigt. Es ist in diesem Fall wieder ein Betrieb durch den Elektromotor möglich.

Furthermore, a method for operating the transmission according to the invention for a hybrid vehicle is preferably provided, the transmission being designed to apply torque at least between an internal combustion engine, an electric motor and a transmission output of a hybrid vehicle, comprising the following steps:

• - Detecting the state of charge of the charge storage device;
• - Continuous analysis and processing of the detected state of charge by the control device of the transmission;
• - Activation of the respective switching mechanisms as a function of the state of charge as soon as this falls below a predefined first battery protection threshold, so that the drive of the hybrid vehicle is forced by the internal combustion engine via the switching mechanisms. The state of charge is measured directly on the charge storage device via corresponding state of charge sensors and transmitted to the control device, which continuously analyzes and processes the state of charge. As soon as the analysis of the current state of charge shows that it falls below a predefined first battery protection threshold, the control device activates the switching mechanisms so that the hybrid vehicle is forced to drive the internal combustion engine. The electric motor is operated in generator mode and charges the charge storage device so that the state of charge of the charge storage device again rises above the first battery protection threshold. In this case, operation by the electric motor is possible again.

• - Erfassen des Wunsches, ob das Hybridfahrzeuges Leistung oberhalb einer Extraleistungsschwelle abrufen soll;
• - Ansteuern der jeweiligen Schaltmechanismen durch die Steuereinrichtung, so dass ausschließlich oder zusätzlich auf die Energie des Elektromotors zum Antrieb des Hybridfahrzeuges zurückgegriffen wird. Die Steuereinrichtung ist somit dazu ausgebildet, zu erfassen, ob der Fahrer zusätzlicher Leistungsreserven zum Betrieb seines Hybridfahrzeuges mobilisieren möchte. Dieser Wunsch wird erfasst, wenn der Fahrer beispielweise das Gaspedal in die Kick-Down-Stellung bringt, oder indem er extra dazu vorgesehene Knöpfe bzw. Programme am Armaturenbrett des Fahrzeuges so einstellt, dass sein Wunsch nach mehr Leistung des Fahrzeuges deutlich wird.

A further preferred method additionally comprises the following steps:

• - Detecting the desire as to whether the hybrid vehicle should call up power above an extra power threshold;
• - Activation of the respective switching mechanisms by the control device, so that the energy of the electric motor is used exclusively or in addition to drive the hybrid vehicle. The control device is thus designed to detect whether the driver mobilizes additional power reserves for operating his hybrid vehicle would like to. This desire is detected when the driver puts the accelerator pedal into the kick-down position, for example, or by setting the buttons or programs on the vehicle's dashboard provided for this purpose in such a way that his desire for more power from the vehicle becomes clear.

• - Vergleichen des erfassten Ladezustandes des Ladungsspeichers mit einem strategischen Batterieschwellenwert durch die Steuereinrichtung;
• - Ansteuern der Schaltmechanismen, so dass bei Unterschreitung des strategischen Batterieschwellenwertes ein Betrieb des Elektromotors zum Antrieb des Hybridfahrzeuges nur noch n-Mal möglich ist. Der strategischen Batterieschwellenwert ist dazu vorgesehen, sicherzustellen, dass immer ausreichend Ladekapazität in dem Ladungsspeicher vorhanden ist, um das Hybridfahrzeug noch n-Mal zu starten. Somit ist immer ein sicherer uns reibungsloser Betrieb des Hybridfahrzeuges gewährleistet.

A preferred method also includes the following steps:

• The control device compares the detected state of charge of the charge store with a strategic battery threshold value;
• - Activation of the switching mechanisms, so that if the strategic battery threshold value is not reached, the electric motor for driving the hybrid vehicle can only be operated n times. The strategic battery threshold value is provided to ensure that there is always sufficient charge capacity in the charge storage device to start the hybrid vehicle n times. Thus, a safe and smooth operation of the hybrid vehicle is always guaranteed.

• 1 eine schematische Schnittdarstellung einer erste, in einem teilweise dargestellten Antriebsstrang eines Kraftfahrzeuges eingesetzten, Getriebeeinheit nach einem ersten Ausführungsbeispiel,
• 2 ein Diagramm zur Veranschaulichung aller durch die Getriebeeinheit der 1 schaltbaren Gänge,
• 3 eine weitere schematische Schnittdarstellung einer Getriebeeinheit nach einem zweiten Ausführungsbeispiel,
• 4 ein weiteres Diagramm zur Veranschaulichung aller durch die Getriebeeinheit der 3 schaltbaren Gänge,
• 5 eine erste schematische Ansicht des Ladezustandes eines Ladungsspeichers,
• 6 ein erstes Diagramm zur Veranschaulichung der Betriebsmodi bei einem Ladezustand entsprechend der 5,
• 7 eine zweite schematische Ansicht des Ladezustandes eines Ladungsspeichers,
• 8 ein zweites Diagramm zur Veranschaulichung der Betriebsmodi bei einem Ladezustand entsprechend der 7,
• 9 eine dritte schematische Ansicht des Ladezustandes eines Ladungsspeichers,
• 10 ein drittes Diagramm zur Veranschaulichung der Betriebsmodi bei einem Ladezustand entsprechend der 9,
• 11 eine vierte schematische Ansicht des Ladezustandes eines Ladungsspeichers,
• 12 eine schematische Ansicht einer Steuereinrichtung und
• 13 eine schematische Ansicht eines Hybridfahrzeuges.

The invention is explained in more detail below with the aid of a drawing. Show it:

• 1 a schematic sectional illustration of a first transmission unit according to a first exemplary embodiment, used in a partially illustrated drive train of a motor vehicle,
• 2 a diagram illustrating all through the gear unit of the 1 switchable gears,
• 3 a further schematic sectional view of a gear unit according to a second embodiment,
• 4th another diagram illustrating all through the gear unit of the 3 switchable gears,
• 5 a first schematic view of the state of charge of a charge storage device,
• 6th a first diagram to illustrate the operating modes in a state of charge corresponding to FIG 5 ,
• 7th a second schematic view of the state of charge of a charge storage device,
• 8th a second diagram to illustrate the operating modes with a state of charge corresponding to FIG 7th ,
• 9 a third schematic view of the state of charge of a charge storage device,
• 10 a third diagram to illustrate the operating modes with a state of charge corresponding to FIG 9 ,
• 11 a fourth schematic view of the state of charge of a charge storage device,
• 12th a schematic view of a control device and
• 13th a schematic view of a hybrid vehicle.

The figures are merely of a schematic nature and are only used for understanding the invention. The same elements are provided with the same reference symbols. In principle, the features of the various exemplary embodiments can be freely combined with one another.

In the 1 is a drive train with a gearbox 1 of a hybrid vehicle 3 clearly visible. The transmission used in this drive train 1 is realized as a hybrid transmission and alternatively also referred to as such. A preferred position of the gearbox 1 of the drive train is in the 13th in a schematically illustrated hybrid vehicle, here a car. It can be seen here that the transmission 1 with the drive train on a front axle of the hybrid vehicle 2 is used effectively and from an internal combustion engine 3 is applied with torque. the 1 also shows an electric motor 4th and a transmission output 5 of the transmission 1 .

According to the training as a hybrid transmission, the transmission 1 a two-stage planetary gear 6th as well as the electrical machine that is actively connected to this planetary gear 4th on. The basic structure of the transmission 1 is particularly good at 1 to recognize. Accordingly, the planetary gear 6th a first planetary gear set 6a on, which forms the first gear stage of the planetary gear and which is shown on the right, and a second planetary gear set 6b , which is the second stage of the planetary gear 6th forms and which is shown on the left.

The first planetary gear set 6a has a first sun gear 20th , a first planetary gear set 21 and a first ring gear 22nd on. The second planetary gear set 6b has a second sun gear 23 , a second planetary gear set 24 and a second ring gear 25th on. The planet gears of the first planetary gear set 21 are on the one hand with the first sun gear 20th , on the other hand with the first ring gear 22nd in mesh. The first planetary gear set 21 is with its individual (first) planet gears on a first planet carrier 26th rotatably arranged. The second planetary gear set 24 is with its individual (second) planet gears on a second planet carrier 27 rotatably arranged. The respective planetary gear sets 21 , 24 are each with the corresponding sun gear 20th , 23 and the corresponding ring gear 22nd , 25th in mesh.

It can be seen that the first sun gear 20th with the electric motor 4th Is rotatably connected and that the first ring gear 22nd with the second planetary gear set 24 is rotatably connected, this connection by a first switching mechanism 8a , here a brake B2, can be fixed to a housing fixed to the vehicle frame.

The second sun gear 23 of the second planetary gear set 6b is through a second switching mechanism 8b , here a brake B1, can in turn be fixed to the housing fixed to the vehicle frame.

The second planet carrier 27 is via a third switching mechanism 8c , here a clutch K2, with the internal combustion engine 3 non-rotatably connectable.

The electric machine 4th typically has a stator and a rotor mounted rotatably relative to the stator, the rotor being rotatably received within the stator. The rotor is rotationally fixed on a drive shaft of the electrical machine 4th attached, the drive shaft with its axis of rotation via a torque output component 28 to the first sun gear 20th is connected. Hence the electric machine 4th with the first sun gear 20th via the torque output component 28 effectively connected. In other versions is the electrical machine 4th with their stator / rotor unit also not necessarily coaxial with the central axis of rotation 28 arranged, but can, for example, with their torque output component 28 coaxial to the central axis of rotation 28 be arranged.
In 1 it can also be seen that in the gear unit 1 on the part of the internal combustion engine 3 basically a torsional vibration damper 30th can be integrated. The torsional vibration damper 30th is here between the output shaft of the internal combustion engine 3 and the input of the gearbox 1 arranged. The torsional vibration damper 30th can in principle as part of the transmission 1 or be arranged as a separate component and, for example, be designed as a two-mass flywheel or as a hydrodynamic damper.

In the 1 are three switching mechanisms 8a , 8b , 8c into the gearbox 1 integrated to the individual gear ratios / gears through their activated or deactivated positions, as they are from the following 2 and 4th emerge, implement.

The first switching mechanism 8a is implemented as a brake B2 and this is between the first ring gear 22nd and the second planet carrier 24 used effectively.

The second switching mechanism 8b is also implemented as a brake B1. The second switching mechanism 8b is between the sun gear 23 and the area fixed to the vehicle frame.

The third switching mechanism 8c is realized as clutch K2 and between the output shaft 31 of the internal combustion engine 3 and the second planet carrier 27 of the second planetary gear set 6b used effectively. So is the output shaft 31 of the internal combustion engine 3 during operation of the hybrid vehicle 2 in the activated position of the third switching mechanism 8c non-rotatably with the second planet carrier 27 of the second planetary gear set 6b connected and in the deactivated position of the second switching mechanism 8c from the second planet carrier 27 of the second planetary gear set 6b rotatably decoupled, ie freely arranged relative to this for rotatable. The activated position of clutch K2 is thus a closed clutch position and the deactivated position of clutch K2 is an open clutch position.

In connection with the 2 until 10 are the individual operating or drive states of the transmission 1 illustrated with the different internal combustion engine gears, the electric machine gears and the EVT gears. In these drive states, either the internal combustion engine acts exclusively 3 , excluding the electric motor or the internal combustion engine 3 supported by the electric machine 4th driving on the output gears 31 .

From the diagram of the 2 It can be seen that a total of six different gears or driving states can be implemented via the three shift mechanisms (brake B1, brake B2 and clutch K2).

By activating the first brake B2 and by deactivating the brake B1 and by deactivating the clutch K2, the electric machine is at a transmission ratio 32 of 3.00 operated in engine mode, the internal combustion engine 3 is deactivated. This represents the second operating mode 9b represent.

In the activated state of the brake B1 and in the deactivated state of the brake B2 and in the deactivated state of the clutch K2, the electric machine is 4th operated in engine mode at a gear ratio of 1.571, with the internal combustion engine 3 is deactivated. This represents the third operating mode 9c represent.

By activating the clutch K2 and by deactivating the brake B1 and the brake B2, the electric machine becomes 4th in the Generator operated and charges the battery. A smaller gear ratio of 1.50 is thereby effected, with the internal combustion engine 3 is activated. This is the first mode of operation 9a .

By activating the clutch K2 as well as by activating the brake B1 and by deactivating the brake B2, the electric motor is operated in generator mode or in motor mode, with the internal combustion engine 3 is activated. There is a fourth operating mode 9d with a gear ratio of 0.714.

By activating the brake B2 and by deactivating the brake B1 and by deactivating the clutch K2, the electric motor is operated in motor mode, the internal combustion engine 3 is deactivated. There is a fifth mode of operation 9d effected with a transmission ratio of 3.00.

By activating the brake B1 and by deactivating the brake B2 and by deactivating the clutch K2, the electric motor is operated in motor mode, the internal combustion engine 3 is deactivated. There is a sixth operating mode 9f caused with a gear ratio of 1.571.

The gear 1 the 3 corresponds to the gearbox 1 the 1 , the third switching mechanism 3 in the 3 by a free-air clutch compared to the clutch K2 of the 1 is replaced. One-way clutches are characterized by the fact that they only transmit torque in one direction. Overrunning clutches are also referred to as backstops, overrunning clutches or as switchable freewheels.

The diagram of the 4th shows the operating states caused by the transmission 1 the 1 are achievable. In the first mode of operation 9a and the fourth mode of operation 9e becomes the overrunning clutch 8c operated in a closed, ie a “locked” state. In the operating modes 9b , 9c and 9d becomes the overrunning clutch 8c operated in an open, ie an “unlocked” state.

the 5 shows a schematic representation of the charge storage device 10 , with different charge states on the vertical axis 33 are applied. The charge states 33 are abbreviated to the term SOC (State of Charge). If the SOC value is 0%, the battery is fully discharged and if the state of charge is 100%, the battery is fully charged. In between there are various SOC values, defined between SOC1 and SOC4. The SOC1 value ranges between 0% and 20%. However, this state between 0% and 20% is not used to ensure that the battery is permanent. This is the unusable area 33 .

A strategic battery threshold is in a SOC value between 20% and 25% 14th provided, which has its lower limit at 20% state of charge. The hybrid vehicle can use this 2 can only be started with a defined number of start processes.

The SOC2 value extends in a range between 25% and 40%, with the first battery protection threshold being at the upper end of this range 11 which corresponds to the SOC2 state. The SOC3 value, i.e. the middle range, ranges between 40% and 80%, with the highest point in this range being the SOC4 value, which is also used as the additional performance threshold 15th referred to as. The uppermost area, which is not used to ensure that the battery is durable, extends between 80 and 100%. This in turn becomes an unusable area 33 designated. The driver of the hybrid vehicle 2 If the range between 0 and 20% and the range between 80 and 100% are not displayed, this range is therefore not available. The state of charge 12th of the load memory 10 is located in the 5 in the middle of the SOC3 area. The battery is thus approximately 60% charged. The transmission is at this state of charge 1 able to the second mode of operation 9b (EM1), the third operating mode 9c (EM2) and the fourth operating mode (ICE4).

the 6th shows a force-speed diagram with different operating states that correspond to the state of charge 12th according to the 5 the battery, i.e. a state of charge 12th , which is located in the middle of the SOC3 area, can be carried out. In the 6th the speed in km / h is plotted on the X-axis, see the reference number 19th . The force in Newtons [N] is plotted on the Y-axis, see the reference symbol 18th . The driving force extends in a range between F = 0N and F = 12,500 N, ie F = 12.5 kN. The speed on the X-axis extends in a range between V = 0 km / h and V = 250 km / h.

Furthermore, different areas are defined, which differentiate the operating areas of the hybrid vehicle: The operating area EM1 extends between a force of F = 7,500 N up to a speed of approx. 40 km / h, then slowly decreases to a speed of 50 km / h. h drops to approx. F = 7,000N and then drops hyperbolic up to a speed of V = 140 km / h to approx. F = 2,000N.

The operating mode EM2, ie the third operating mode 9c , starts at approx. 140 km / h and slowly decreases up to approx. F = 2,500 N at a speed of V = 150 km / h.

The boost area is located above the EM1 and EM2 areas 17th . The boost range is brought about by the internal combustion engine being connected to the constant drive with the electric motor. The boost range extends in a range between approx. V = 60 km / h with a drive force of F = 7,600N and drops down to a speed of V = 250 km / h with a drive force of approx. F = 2,700N .

The peak area is in the front area above the EM1 area 16 . Starting from a force of F = 11,000N, this extends horizontally up to a speed of approx. V = 50 km / h and then drops steeply to a speed of approx. V = 60 km / h with a force of approx = 7.500N.

the 7th shows the charge storage 10 , the state of charge 12th of the charge storage 10 is located at approx. 25% of its full capacity.

At this charge level 12th of the charge storage 10 are those in the 8th operating states shown can be reached. The first mode of operation 9a , ie the operating mode ICE2 in EVT mode starts at a force of approx. F = 4,000 N and extends horizontally up to a speed of approx. V = 60 km / h and steadily decreases to a force of approx. F = 3,000 N at approx. V = 140 km / h. That means, during the start-up process at low speeds and in one state of charge 12th of the battery, which moves in the lower third, the car runs in combustion mode.

The ICE4 mode, ie the fourth operating mode 9d , starts at approx. F = 2,000 N at a speed of approx. V = 60 km / h and extends slowly decreasing to a speed of V = 250 km / h and ends at approx. F = 2,000 N. Above the range 9b the boost range is located starting at a force of approx. F = 7,000 N and a speed of V = 60 km / h 17th . The boost section 17th falls steadily from F = 7,000 N at a speed of V = 60 km / h down to a speed of V = 250 km / h and a force of approx. F = 2,700 N.

Above the area 9a , ie the ICE2 area in EVT mode, is the end area 16 which is also EM1 + peak area 16 and which starts at approx. F = 11,000 N with a speed of approx. V = 0 km / h and which extends horizontally up to a speed of approx. V = 50 km / h and then rapidly drops to a force of approx. F = 7,000 N and a speed of approx. V = 60 km / h.

In the 9 is the charge storage 10 shown up to the state of charge 12th is charged, ie which is at approx. 20% of the full state of charge of the battery, ie below the strategic battery threshold value 14th or exactly at the limit of the strategic battery threshold 14th .

The first operating mode, ie the recuperation mode 9a , is between a force F = 4,500 N, starting at a speed of V = 0 km / h, runs horizontally up to a speed of V = 60 km / h and then decreases steadily to a speed of V = 150 km / h depends on a force of approx. F = 2,600 N. Above this range there is no longer an operating range, since the battery is almost empty and therefore a peak range can no longer be provided by an additional operation of the electric motor. The ICE4 area, ie the fourth operating mode 9d starts at a force of approx. F = 2,400 N at a speed of approx. V = 60 km / h and extends slowly downwards horizontally to a force of approx. F = 2,400 N up to a speed of approx. V = 250 km / h. There is no further boost range above this range either, since the battery, ie the charge memory, is almost empty.

the 11 shows the charge status 12th of the load memory 10 , the state of charge 12th below the strategic battery threshold 14th moves, so the battery is almost empty. Below the strategic battery threshold 14th the hybrid vehicle can only be driven n times by the electric motor. The value n times depends on the defined level of the strategic battery threshold value 14th and other framework conditions, such as, for example, the gradient or the incline on which the hybrid vehicle is standing, the outside temperature, the air humidity or other framework conditions that depend on the respective area of use.

In other words, a transmission is provided which additionally contains an EVT mode, ie a combustion mode on which a drive of the electric motor in generator mode can also be acted upon. It is thus advantageously possible to carry out most of the starts with the internal combustion engine when the charge store, ie the battery, is being charged. Different start and mode usage strategies must be defined according to the different SOC (State of Charge) thresholds. The strategies described apply to Dedicated Hybrid Transmission (DHT) with at least two electrical forward gears, one EVT gear and a gear ratio for the combustion engine. At least two electrical gears are used for reversing, in which the electric motor runs in the other direction, ie in the reverse direction. Depending on the Different charging states of the battery, rules are defined for the use of the various available gear ratios or modes, depending on the desired vehicle speed and the desired drive force.

the 12th shows a schematic representation of the parameters that affect the control device 7th works. The control device 7th is designed to use the first battery threshold 11 , the state of charge of the charge storage 12th , the extra performance threshold 13th , the strategic battery threshold 14th and the additional benefit threshold 15th to be processed as operating parameters. The control device then controls the switching mechanisms as a function of these parameters 8a , 8b , 8c so that these are based on a stored control algorithm and the parameters 11 , 12th , 13th , 14th , 15th can be controlled.

the 13th shows a schematic representation of a hybrid vehicle 2 , comprising multiple drive wheels 31 that one of the gearboxes 1 are driven, which in turn by the internal combustion engine 3 is driven. The internal combustion engine can be designed as a gasoline or diesel engine.

List of reference symbols

1

transmission

2

Hybrid vehicle

3

Internal combustion engine

4th

Electric motor

5

Transmission output

6th

Planetary gear

6a

first planetary gear set

6b

second planetary gear set

7th

Control device

8a

first switching mechanism

8b

second switching mechanism

8c

third switching mechanism

9a

first operating mode (recuperation mode)

9b

second operating mode

9c

third mode of operation

9d

fourth operating mode

9e

fifth mode of operation

9f

sixth operating mode

10

Charge storage

11

first battery saving threshold

12th

State of charge of the charge storage

13th

Extra performance threshold

14th

strategic battery threshold

15th

Additional benefit threshold

16

Peak area

17th

Boost area

18th

Force [N]

19th

Vehicle speed [km / h]

20th

first sun gear

21

first planetary gear set

22nd

first ring gear

23

second sun gear

24

second planetary gear set

25th

second ring gear

26th

first planet carrier

27

second planet carrier

28

Torque output component

29

Axis of rotation

30th

Torsional vibration damper

31

Drive wheels

32

Gear ratio

33

Unusable area

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• EP 3315372 A1 [0005]
• DE 102016221045 A1 [0006, 0007]
• EP 2146855 B1 [0008]
• WO 2016/075336 [0009]
• DE 102018130498 A1 [0010]

Claims (10)

Transmission (1) for a hybrid vehicle (2) in order to pass torque at least between an internal combustion engine (3), an electric motor (4) and a transmission output (5), comprising a planetary gear (6) located in the torque flow, which is controlled by a control device ( 7) can be switched into several operating modes (9a, 9b, 9c, 9d, 9e, 9f) by several switching mechanisms (8a, 8b, 8c), one of which is a recuperation mode (9a, 9b, 9c, 9d, 9e, 9f) (9a), in which the internal combustion engine (3) acts as a driving force and the electric motor (4) is provided in generator mode to charge an operatively connected charge storage device (10), characterized in that at least one first battery protection threshold value (11 ) is stored, which reproduces a state of charge (12) of the charge storage device (10), the control device (7) being set up to switch the switching mechanisms (8a, 8b, 8c) so a To control that the drive of the hybrid vehicle (2) is forced by the internal combustion engine (3), so that the hybrid vehicle (2) is operated in recuperation mode (9a). Gear (1) Claim 1 , characterized in that the control device (7) is pre-set up to control the switching mechanisms (8a, 8b, 8c) in such a way that the switching mechanisms (8a, 8b, 8c) are activated exclusively or additionally on the energy of the electric motor ( 4) is used to drive the hybrid vehicle (2). Gear (1) Claim 1 or Claim 2 , characterized in that a strategic battery threshold value (14) is stored in the control device (7), the control device (7) being pre-set up to control the switching mechanisms (8a, 8b, 8c) when the strategic battery threshold value (14) is not reached that the electric motor (4) can only be operated n times to drive the hybrid vehicle. Gear (1) Claim 3 , characterized in that the value is determined n times by the control device (7) as a function of the stored strategic battery threshold value (14) and other framework conditions, such as downhill or uphill gradient on which the hybrid vehicle (2) is standing. Gear (1) according to one of the Claims 1 until 4th , characterized in that a control algorithm is stored in the control device (7) which forces the switching mechanisms (8a, 8b, 8c) to switch mechanisms (8a, 8b, 8c) when the charge store (10) reaches a state of charge (12) above the first battery protection threshold (11) be controlled so that the electric motor (4) is used to drive the hybrid vehicle (2). Gear (1) Claim 5 , characterized in that the control algorithm is designed so that above a desired additional power threshold (15) the switching mechanisms (8a, 8b, 8c) are controlled by the control device (7) in such a way that the electric motor (4) is in a peak range ( 16) is operated, or the internal combustion engine (3) is switched on in order to implement operation in a boost range (17). Hybrid vehicle (2) comprising an internal combustion engine (3), an electric motor (4) and the transmission (1) according to one of the Claims 1 until 6th to spend torque at least between the internal combustion engine (3), the electric motor (4) and the transmission output (5). Method for operating the transmission (1) according to one of the Claims 1 until 6th for a hybrid vehicle (2), the transmission (1) being designed to deliver torque at least between an internal combustion engine (3), an electric motor (4) and a transmission output (5) of a hybrid vehicle (1), comprising the following steps: - Detecting the state of charge (12) of the charge store (10); - Continuous analysis and processing of the detected state of charge (12) by the control device (7) of the transmission (1); - Activation of the respective switching mechanisms (8a, 8b, 8c) depending on the state of charge (12) as soon as this falls below a predefined first battery protection threshold value (11), so that the drive of the hybrid vehicle (2) by the internal combustion engine (3) via the switching mechanisms ( 8a, 8b, 8c) is forced. Procedure according to Claim 8 , additionally comprising the following steps: - detecting the desire whether the hybrid vehicle (2) should call up power above an extra power threshold (13); -Control of the respective switching mechanisms (8a, 8b, 8c) by the control device (7), so that the energy of the electric motor (4) is used exclusively or in addition to drive the hybrid vehicle (2). Method according to one of the Claims 8 or 9 , additionally comprising the following steps: - the control device (7) compares the detected state of charge (12) of the charge store (10) with a strategic battery threshold value (14); - Control of the switching mechanisms (8a, 8b, 8c), so that if the strategic battery threshold value (14) is not reached, the electric motor is operated (4) is only possible n times to drive the hybrid vehicle.

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