DE10035027A1 - Method for controlling the operating mode of vehicles with hybrid drives detects a route profile covered by a vehicle while invoking an additional criterion for selecting the operating mode - Google Patents

Abstract

A route profile can be known in advance or detected through sensors. As further criteria, the route profile can be supplemented with the dynamics of vehicle movement, the behaviour of the driver and available electrical driving power.

Description

The invention relates to a method for controlling the loading drive mode of vehicles with hybrid drives according to Oberbe handle of claim 1 and a corresponding control unit according to the preamble of claim 10.

Vehicles with hybrid drive have a common Ver internal combustion engine to drive an electric motor. By suitable Choice of operating mode, d. H. by switching between ver internal combustion engine, electromotive and mixed Be driven, the fuel consumption of the vehicle can be interpreted lower.

From DE 196 17 548 A1 it is known, depending on Predefinable priorities that exist in the vehicle and generate electrical energy metered to various consumers share, prioritizing one or more of the following Criteria can be selected: maximum range; minimal force material consumption; maximum mileage; maximum comfort. at The priority of minimum fuel consumption is about the up Charge of the energy storage (battery) by the combustion engine or the internal combustion engine drive as long as possibly avoided.

DE 40 00 678 A1 describes a controller for a motor vehicle with an internal combustion engine, one of which is driven NEN generator, a flywheel storage and an electromo Tor known that the internal combustion engine based on the charging situation on the flywheel storage and / or the power delivery situation  controls the electric motor so that the combustion engine gate with a first (power) speed or with a second (idle) speed runs. Based on the above According to the teaching of this document, criteria are also possible the internal combustion engine to higher or lower output stung, also from the point of view of fuel consumption or control pollutant emissions.

Furthermore, a hybrid vehicle is described in DE 198 05 972 A1 wrote that an internal combustion engine, one of these powered electric generator, an electrical energy storage device as well as an electric motor, which by the from the electrical energy storage device trical energy is operated. A gradual reduction Storage capacity due to repeated charging / discharging to avoid the storage device, it is proposed here to divide them into a plurality of storage parts, wel be loaded and unloaded independently of each other can, with a certain memory part only full should be constantly unloaded or loaded. Furthermore, a Operation control device proposed to switch between several suitable for different operating modes of the hybrid drive select. The operational control device receives the off gear signals including an acceleration and Ge speed sensor and an electric motor and combustion planning engine speed sensor. For example, the company chooses control device between the operating modes combustion engine drive, electric motor drive and combustion motor drive with charging the electrical energy store suitable operating mode based on the total amount of ge stored electrical energy. In a driving condition high Load can be on a combined combustion engine be switched / electric motor drive.

For optimal use of the capacity of a battery in one Hybrid vehicle is described in JP 80237810 (application number: 1995 64996) and JP 80126116 (application number: 1994 285834)  proposed, with known distance to be covered and with ge measured consumption and measured remaining battery power the electromotive drive power suitably to deliver. The use of fuzzy logic to control Hybrid drives are known for example from JP-11262105 (application denummer: 1998 JP 10-57988) or JP-10051909 (application number: 1996 JP 08-204531) and with the help of a navigation system stems from JP-08140215 (application number: 1994 JP 06-298799) known.

To make vehicles with hybrid drive attractive to the public To make it tive, the fuel savings must be above one compensate for the additional purchase costs for a certain period. It has shown that the majority of the fuel saving tentials realized with less powerful electric motors can be. These are able to drive the vehicle at a low dynamics up to speeds of 30 or 50 km / h to operate, however, are at a higher dynamic than that city traffic is no longer sufficient. The choice of loading drive mode of the hybrid drive (purely combustion engine, purely electric or mixed drive) must therefore be situati due to ons. For this, as in the mentioned DE 198 05 972 A1 describes various criteria as recorded Driving dynamics, recorded driver behavior and / or currently ver available electrical drive power can be used. The Driving dynamics are made here via parameters such as vehicle speed speed, vehicle acceleration and the speed of the electrical or internal combustion engine shown. The driver behavior will based on the accelerator pedal actuation and pedal actuation speed classified. The currently available electrical type drive power is measured.

In practice, operating mode control units have the disadvantage that either in favor of sufficient driving dynamics operate and pass constant speed phases where through the potential for fuel-saving, purely electrical Operation remains unused, or that the other way around immediately  Driving phases react at a constant speed and on switch electrical operation, which often causes the driving dynamics mik unacceptable for the user (e.g. in city traffic) becomes.

Vehicles are used to determine standard consumption agreed to test conditions, in Europe the "New Eu European driving cycle "(NEDC) or in the U.S.A. the" US City Cycle "(FTP 75). For the marketability of a hybrid drive it is essential to be good at going through such standard cycles To achieve values.

The object of the present invention is therefore an improved loading drive mode control for vehicles with hybrid drive ben, the operating mode control especially when through run from test cycles to determine the standard consumption good Should deliver values.

This object is achieved by the features of Pa Tent claims 1 and 10 solved. Advantageous configurations result from the respective subclaims.

To control the operating mode, the invention uses as additional criterion is the recorded route profile. hereby it becomes possible to better meet the respective mileage requirements appreciate. The mileage requirement does not just depend of the driving dynamics recorded and the driver behavior but can differ greatly in whether a Route with increasing incline, with changing headwinds or is driven on with changing road conditions.

Accordingly, driving resistance parameters such as incline, Track surface and headwind to determine a track pro suitable for fils. The track surface varies depending on whether the Lane is dry, wet or covered with snow. Here is it makes sense to also use the vehicle load hen that significantly influences vehicle behavior.  

As further parameters for determining the route profile NEN the course of the road, intersections with traffic lights, signposted other intersections, prescribed maximum speeds given gradients etc., but also on the one to be driven Accidents, traffic jams, etc. that have occurred on the route.

The last mentioned parameters can be used in advance tels GPS (Global Positioning System) technology, navigation system men or traffic management systems can be detected.

By the inventive inclusion of the criterion "stretching profile "to control the operating mode of a vehicle with Hybrid drive can make the operating mode more reliable than before on the driving performance and dynamics required driver's request.

Unlike before, the internal combustion engine can be uncoupled with a time delay to be determined in each case be taken if, for example, a distance of constant Ge dizziness. This time delay is determined by the criteria mentioned, being a fuzzy logic can be used for the calculation. In the simplest case leaves the recorded speed profile of the route traveled to determine this delay time. The Ge The speed profile gives the dynamics of the route profiles again, but also about the steepness (slope inclination) of the speed curve the influence of the driver insurer. The delay time until the combustion decouples motors is suitably chosen the larger the higher the preceding dynamics (rate of change) of the measured Ge speed profile is. For the execution described here Protection form of the invention is claimed independently protection.

The internal combustion engine is switched on again Again, according to the criteria mentioned, whereby here the criteria "route profile" (driving performance requirement)  and "electric motor available power" is the primary Role-play. Is namely the currently available electrical Drive power for the required mileage no longer sufficient, the combustion engine must be switched on In the simplest case, the measured Ge Speed profile give information. Great slope is an indication of an increased mileage requirement and / or for a high dynamic demand from the driver. The how The internal combustion engine can be switched on in such a way Case after a delay time to be determined depending on the slope of the speed profile or according to Er a predetermined threshold speed is successful Independent protection is also provided for this configuration claimed.

It is advantageous to use the operating mode with disconnected Ver to further differentiate the internal combustion engine as to whether the Internal combustion engine completely switched off, operated at idle or is operated at an increased idle speed. Is a expect a longer distance at constant speed the internal combustion engine can be switched off. However, is after a constant speed route with an increased Fahrlei the internal combustion engine should continue to calculate be operated at idle. An increased idle speed is recommended for increased dynamic requirements, i. H. at consecutive coupling and uncoupling of the combustion voltage motors.

The operating mode control device according to the invention contains a Decision making unit based on the listed criteria decides on the respective drive form. Vorteilhafterwei This decision unit uses fuzzy logic. Furthermore, the use of learning programs is advantageous, through the example of the route profile and Fah optimal behavior of the operating mode is determined can be. With such a control device can then under be divorced whether the driver is at low speed  located in a housing estate (low demands on the driving dynamics; purely electrical operation) or whether the driving in city traffic in a green wave (electri Operation possible, but with the willingness to burn engine at idle).

In the following, exemplary embodiments are intended to illustrate the invention explain the accompanying drawings.

Fig. 1 shows a block diagram of the operation mode control system according to the invention,

Fig. 2 shows the standard cycle "New European Driving Cycle" (NEDC) and the intervals H and O, in which the dung OF INVENTION Proper operation mode control decouples the Verbrennungsmo gate,

Fig. 3 shows the standard cycle "US City cycle" (FTP 75 ) and the intervals A to G, in which the operating mode control system according to the invention decouples the internal combustion engine.

Fig. 1 operation mode control unit according to the invention shows a strongly simplified block diagram in shape. In this exemplary embodiment, the control unit has the following detection units: a detection unit 1 according to the invention for detecting a route profile to be traveled, a detection unit 2 for detecting driving condition parameters such as acceleration, speed or speeds of the electric motor or internal combustion engine, a detection unit 3 for detecting it the available electrical drive power (battery charge state), whereby a critical heating of the units should advantageously be detected, and a detection unit 4 for driver behavior, which can be classified based on the pedal movements and / or the gear selection processes. The registration units 1 to 4 are equipped with appropriate sensors and receivers. In this embodiment, the decision criteria selected in each case are evaluated using fuzzy logic, for example. This evaluation takes place in the decision unit 5 , in which an operating mode is selected on the basis of the result. Basically, the three operating modes internal combustion engine, electric motor and mixed drive are available. Of course, further differentiations can be made, for example an internal combustion engine drive with simultaneous charging of the battery.

It makes sense to make a further differentiation by means of a further decision unit 6 within the operating mode electromotor operation. This determines the speed of the internal combustion engine in electromotive operation, whereby the internal combustion engine can either be switched off completely, operated at idle speed or operated with the standby speed raised. This differentiation is also suitably carried out using fuzzy logic. If the detected (or known) route indicates that a longer constant driving section follows, the combustion engine can be switched off completely. In a constant driving section interrupted by intersections and traffic lights, it makes sense to keep the internal combustion engine decoupled from idling. On a route with high dynamics, it is advisable to provide the internal combustion engine uncoupled at increased engine speed during electromotive operation.

In the following, the control method according to the invention is intended the operating mode based on with a tax according to the invention continuous cycle of standards, the New European Driving cycle (NEDC).

Fig. 2 shows the speed profile for a vehicle with hybrid drive, which runs through the standard cycle with the operating mode control according to the invention. Sections H to O have a purely electric motor drive. These periods predominate those in which the internal combustion engine is switched on or a purely internal combustion engine drive takes place. The electric motor can handle constant speeds of up to almost 60 km / h. If the acceleration phases (positive slope) between the constant travel sections are not too high, the internal combustion engine can remain uncoupled. The coupling of the internal combustion engine takes place according to the invention only after a delay time, which is measured on the one hand by the available power of the electric motor, and which on the other hand depends on the current driving performance requirement. Accordingly, due to the different accelerations that occur at the end of sections I, J and M, the internal combustion engine is switched on at different speeds. This allows particularly fuel-saving operation with sufficiently high driving dynamics. If a drop in speed is registered with sufficient steepness when the internal combustion engine is switched on, the internal combustion engine can be uncoupled without a time delay (see start of intervals N and O). Conversely, as can be seen from the area between the intervals I and J, the coupling of the internal combustion engine does not immediately enter the constant driving phase, but only after a time delay that depends on the preceding driving dynamics.

Fig. 3 shows the speed profile of a vehicle equipped with the inventive mode control system with hybrid drive after going through a highly dynamic standard cycle, the "US City Cycle" (FTP 75). Here, too, denote the intervals A to 6 periods in which the internal combustion engine is disconnected.

Fig. 3 shows that only a small amount of time A to 6 remain in the highly dynamic city cycle, in which the combustion engine can be uncoupled and optionally switched off.

According to the invention, for example, in the time phase A, the internal combustion engine is not decoupled at the beginning of the deceleration phase (negative acceleration), but only after a deceleration time to be determined, which is longer than z. B. in the time phase N in Fig. 2, where the delay times for the change in operating mode are greatly shortened due to the long constant travel shares.

The start of the decoupling phase A in Fig. 3 is not only determined by the highly dynamic previous route profile, but also by the driver's influence, which is only indirectly expressed in the image by the steepness of the speed curve.

The switch-on time of the internal combustion engine (end of phase A) depends primarily on the driving performance requirement and the available power of the electric motor. In the example in FIG. 3, at the end of the time period A, the power limit for the required acceleration occurring is given at 13 mph. In the highly dynamic process shown here, it is recommended to disconnect the internal combustion engine at an increased standby speed.

The operating mode control according to the invention enables one particularly fuel-saving operation with simultaneous loading taking into account the required route dynamics and that of Driver desired driving dynamics.

Claims (15)

1. A method for controlling the operating mode of a vehicle with a hybrid drive, the operating mode being determined at least by one of the drive types of internal combustion engine, electromotive and mixed drive, and the selection of the operating mode based on criteria such as detected driving dynamics, detected driver behavior and / or Available electrical drive power takes place, characterized in that the route profile traveled by the vehicle is detected and used as an additional criterion for the selection of the operating mode. 2. The method according to claim 1, characterized in that the Route profile based on driving resistance parameters such as Stei supply, track surface and headwind, possibly involving the respective vehicle load is detected. 3. The method according to claim 1 or 2, characterized in that the route profile based on data on the road ver run, especially incline, intersections with / without traffic lights and closed casual top speed, and / or the traffic situation, how accidents, traffic jams are determined. 4. The method according to any one of claims 1 to 3, characterized records that using GPS (Global Positioning System) technology, Navigation systems or traffic management systems the route pro fil is partially recorded in advance.   5. The method according to any one of claims 1 to 4, characterized records that for changing the operating mode by Abkop The internal combustion engine primarily meets the criteria Route profile and driver behavior are used. 6. The method according to claim 5 or the preamble of the An Proverb 1, characterized in that the transition to the elec tromotor drive by uncoupling the internal combustion engine after a delay period made by the before assumed driving dynamics and / or from the previous one Route profile and depends on the recorded driver behavior. 7. The method according to any one of claims 1 to 6, characterized records that for changing the operating mode by Zu switch the internal combustion engine primarily the criteria Route profile and available electric drive power be used. 8. The method according to claim 7 or the preamble of the An Proverb 1, characterized in that the transition to ver internal combustion engine or mixed drive by switching on of the internal combustion engine after a delay time is that of the detected driving dynamics and / or the detected Route profile and the available electric drive line depends on. 9. The method according to claim 5 or 6, characterized in that that the uncoupled internal combustion engine either completely abge switches, operated at idle or with increased idle speed is operated. 10. Control unit for selecting the operating mode of a hybrid drive for a vehicle with detection units ( 2 , 3 , 4 ) for decision criteria such as detected driving dynamics, previous detected driver behavior and available electrical drive power and with a decision unit ( 5 ) based on the detected decision criteria selects the cheapest operating mode, characterized by a further detection unit ( 1 ) for detecting a route profile to be traveled. 11. Control device according to claim 10, characterized in that the detection unit ( 1 ) sensors for detecting Fahrwi derstandparameters, such as slope, road surface and counter wind, and possibly sensors for detecting the respective vehicle load. 12. Control device according to claim 10 or 11, characterized in that the detection unit ( 1 ) for receiving and processing of GPS (Global Positioning System) signals, signals from navigation systems and / or from traffic control systems is equipped. 13. Control device according to one of claims 10 to 12, characterized in that a further decision unit ( 6 ) is seen before, which determines the speed of the internal combustion engine in elec tromotor operation, the internal combustion engine in particular either switched off, operated at idle or with increased standby speed can be operated. 14. Control device according to one of claims 10 to 13, characterized in that the decision unit ( 5 ) for fixing the operating mode and / or the decision unit ( 6 ) for determining the speed of the internal combustion engine by means of fuzzy logic from the detected decision criteria the most favorable Operating mode or the cheapest speed determined. 15. Motor vehicle with one according to one of claims 1 to 9 controlled hybrid drive or a control unit after a of claims 10 to 14.