WO2011042182A1

WO2011042182A1 - Vehicle having an electrical drive and reversible safety components

Info

Publication number: WO2011042182A1
Application number: PCT/EP2010/006127
Authority: WO
Inventors: Rainer Justen
Original assignee: Daimler Ag
Priority date: 2009-10-08
Filing date: 2010-10-07
Publication date: 2011-04-14
Also published as: DE102009048711A1

Abstract

The invention relates to a vehicle (1) having an electrical drive (E), a high voltage network (HV) for the electrical drive and for high-power consumers, and a low voltage network (LV) for low-power consumers. According to the invention, a control device (ECU) can electrically connect a reversible safety component (RS) to the high voltage network (HV) as a low-power consumer. The invention solves the problem of better integrating a reversible safety component in a vehicle having an electrical drive.

Description

Vehicle with electric drive and reversible safety component

The invention relates to a vehicle with electric drive having the features of the preamble of claim 1.

From the generic DE 10 2005 051 433 A1 a method is known in connection with a 42 V electrical system for controlling a generator in a two-voltage electrical system of a motor vehicle. For regenerative braking, the vehicle is equipped with a recuperation device, which can buffer brake energy. For intermediate storage, a capacitor can be charged and discharged by means of a control device as a function of a vehicle speed at the beginning of a recuperation phase. A voltage circuit is preferably designed for high-power consumers in which voltage fluctuations are not relevant to safety. As examples of high-performance consumers are an interior auxiliary heater for comfort increase and a

Windscreen heating called. The font does not run any security-related applications.

US Pat. No. 7,343,999 B2 describes a method for driving a belt tensioning system for a safety belt. A first and a second voltage source are adapted to drive a motor of the belt tensioner system to meet different requirements for the tightening of the webbing. The second

Voltage source is charged by the first and provides after charging a higher voltage than the first voltage source. It is a monitoring of the state of charge of the second voltage source required. If there is a risk of injury to a vehicle occupant, depending on the risk of injury, either the first or the second voltage source to the engine of the

Belt tensioner system can be connected. The first voltage source is

connected if it is intended to connect the second, but this is not sufficiently charged. A webbing is faster by the belt tensioner system Tightened when the engine of the belt tensioner system is driven by a higher voltage.

The object of the invention is better to integrate a reversible safety component in a vehicle with electric drive.

This object is achieved by the features of claim 1, wherein the features of the claims characterize advantageous embodiments and further developments.

The invention relates to a vehicle with an electric drive. The vehicle includes a high-voltage network, which is provided for the electric drive, but can also be provided for high-power consumers. In addition, the vehicle includes a low-voltage network for low-power consumers. A control device in the vehicle, which is a low-power consumer, can electrically connect a reversible safety component of the vehicle to the high-voltage network. It is not

Monitoring the state of charge of the high-voltage network necessary, since the high-voltage network is available during the entire operating time of the vehicle.

A low power consumer requires significantly less electrical power to operate it than a high power consumer. With the same voltage, therefore, a higher current would flow during operation of the high-power consumer than during the operation of the low-power consumer.

The electric drive is used for locomotion of the vehicle and is preferably designed as an electric motor. The electric drive can - as in an electric vehicle - serve as the sole drive of the vehicle or as an additional drive. An example of a use of the electric drive as an auxiliary drive is a hybrid vehicle, in which additionally an internal combustion engine directly or indirectly serves as a drive source for the movement of the vehicle. The electric drive can be

Be a heavy-duty consumer.

The low voltage network is especially for the power supply of

Designed for low power consumers, ie for the power supply of electrical consumers with lower power such as control units or signal processing equipment. It essentially corresponds to a 12 V or 14 V electrical system commonly used in current vehicles, so that in principle also other Low-power consumers can be connected to the low-voltage network. Control devices and devices for signal processing are usually sensitive to glitches or voltage fluctuations, which can be caused for example by electric motors when they are connected to the low-voltage network. The more powerful an electric motor is, the greater the glitches and voltage fluctuations it generally causes. For electrical

Components which are designed for operation on the low-voltage grid, it is advantageous that these are among other cheap and easily available.

The high voltage network is especially for the power supply of

Designed high-power consumers, ie for the supply of the electric drive and for the supply of other high-power consumers, such as an electric actuator. The power required by the high-power consumers can not provide the low-voltage network or only to a limited extent. The voltage of the high-performance network is higher than the voltage of the low-voltage network. In typical embodiments, the voltage of the high voltage network may be 42V, 130V or 400V. Due to the higher voltage, higher powers can be better achieved since, for example, a cross section of a supply line between the voltage source and the load can be lower or the supply line is heated less at a current flow.

Of course, another embodiment is possible in which more than two

Voltage networks are included. In one version, a 12 V electrical system is combined with a 42 V and a 130 V electrical system, whereby the 12 V electrical system is preferred for

Low-power consumer, the 42 V vehicle electrical system preferred for high-performance consumers and the 130 V electrical system is preferably provided for the electric drive.

A limit from which a voltage network is to be regarded as a low or high voltage network may depend on technical boundary conditions. For example, the 42 V electrical system is repeatedly proposed as a replacement for the 12 V electrical system. In one embodiment, the high voltage network has a voltage higher than 60V. The low-voltage network in this case has a voltage which is lower than 60 V, that is, for example, 12 V, 14 V or 42 V. The voltage of

High-voltage network can be significantly dependent on which drive or power supply concept has the electric drive of the vehicle. The

Power supply concept may depend significantly on a type of battery used. In today's electric vehicles, which also include hybrid vehicles, typical voltages of the high voltage network between 100 V and 600 V, with currently 130 V, 400 V or 600 V are common.

The control unit is preferably connected as a low-power consumer to the power supply to the low-voltage network, can in principle with appropriate

Design for power supply but also be connected to the high-voltage network. The control unit is able to electrically connect a reversible safety component to the high-voltage network in order to activate the reversible safety component. Such an electrical connection is preferably carried out by a controlled by the control unit switch or controller, which may be integrated, for example, in the control unit or in the reversible safety component. As a switch or regulator can be used about a power transistor. The electrical connection of the reversible safety component to the high voltage network causes an actuator to activate the reversible safety component of the

High voltage network is fed with electrical energy. A common one

Exemplary embodiment of such an actuator is an electric motor. Another example of such an actuator is an electrically controllable valve, by which a pneumatically or hydraulically movable piston can be controlled.

The reversible safety component may also contain at least one additional component in addition to the actuator. A supplementary component can also be electrically connected to the low-voltage network. In one embodiment, the reversible safety component is equipped with a separate control unit as a supplementary component, wherein the separate control unit can perform tasks of the control unit. The reversible safety component can be combined with an irreversible safety component. An example of an irreversible

Safety component is a pyrotechnic actuator, as used for example in a pyrotechnic belt tensioner. An irreversible safety component can not be activated repeatedly.

The reversible safety component is intended to reduce an accidental load and thus a risk of injury to an occupant of the vehicle. It can be activated repeatedly. The activated reversible safety component offers the occupant an increased level of safety compared to the deactivated reversible safety component

Occupant protection in case of a possible accident of the vehicle. The reversible safety component is in particular a reversible belt tensioner, an adjustable seat component, an adjustable window, a sunroof or an adjustable support surface. Of course, several reversible

Safety components are combined. As a preferred actuator for the reversible safety component is in particular a motor, preferably a

Electric motor, an electromagnet, an electrically operated valve, a pump for a gas or for a liquid or another transducer used, which converts an electrical signal directly or indirectly into mechanical movement.

An adjustable support surface serves an earlier or additional support of the occupant. For example, a glove box, which in front of a

Frontal impact is adjusted in a direction towards the occupant direction, the occupants additionally or earlier supported by energy absorption. Due to the additional or earlier support, an impact-related maximum occupant load can be reduced. Alternatively or additionally, the adjustable support surface can influence a kinematics or a position of the occupant. For example, the occupant may be more vulnerable to injury due to an occupant-adjustable portion of a side door trim prior to or during a side impact

Deformation zone are pushed.

If the reversible safety device comprises an adjustable supporting surface for the occupant, then in one embodiment this has an energy-absorbing property. In one embodiment, the energy absorbing feature is formed by a foam layer or by some other compliance of the support surface with energy absorption.

For a risk assessment regarding the risk of injury to the occupant of the vehicle at least one sensor is evaluated. For this purpose, a conventional sensor or a conventional system with at least one sensor is suitable, such as a vehicle dynamics stability system, which detects a skid of the vehicle, a brake assist system to support a braking operation of the vehicle, a sensor for detecting obstacles in the environment of the vehicle or a

Acceleration sensor suitable for measuring delays of the vehicle. The evaluation of the sensor is carried out by the control unit or by another

Control unit, which informs the control unit about danger assessment. With a high risk assessment, the control unit combines the reversible

Safety component with the high voltage network. At a low By contrast, the control unit combines the reversible safety component with the low-voltage grid. Of course, switching can also depend on other conditions. A low risk assessment assumes a lower risk of injury to the occupant than a high risk assessment.

If the reversible safety component is connected to the low-voltage network, the reversible safety component causes additional occupant protection for the occupant, which acts in addition or as an alternative to the other safety components. If the reversible safety component is connected to the high-voltage network, it offers the occupant an increased additional occupant protection, which is even more effective than the additional occupant protection, which with the

Low-voltage network connected reversible safety component causes.

In one embodiment, a reversible pretensioner tightens a webbing of a safety belt with little force when an electric motor of the reversible pretensioner is connected to the low voltage network. If the electric motor of the reversible belt tensioner connected to the high-voltage power, the reversible belt tensioner tightens the belt of the seat belt with a strong force, which is stronger than the low force. Alternatively or additionally, the reversible belt tensioner tightens the webbing faster when it is connected to the high voltage network than when it is connected to the low voltage network.

The low force of the reversible belt tensioner is suitable for example

a webbing retraction for the preventive reduction of a belt slack of a belt belt loosely attached to the belted occupant when the vehicle is stationary, during normal driving or during critical driving,

- A dynamic vehicle occupant fixation on the webbing during a

Cornering or

- A pre-tightening of the webbing before an accident.

The strong force of the reversible belt tensioner is suitable, for example, for a stronger dynamic driving occupant fixation, for a stronger or faster pre-tightening of the webbing before the accident, for a retraction of the occupant in a vehicle seat before the accident or before an airbag deployment or for pre-acceleration of the occupant just before the accident or at the beginning of the accident, to a maximum

Reduce occupant exposure during the accident. In the particularly advantageous integration of a reversible safety component in a vehicle with electric drive another issue is to be considered in addition to the improvement of occupant protection. High-performance consumers such as high-performance electric motors are much less sensitive to glitches or voltage fluctuations than control units. Therefore, that will

High-voltage network designed in an advantageous embodiment such that therein greater voltage fluctuations or stronger interference pulses are allowed as in the low-voltage network without a normal operation of connected to the respective network components is impaired. This allows a distribution of less interfering components for connection to the

Low-voltage network and more disruptive components for connection to the high-voltage network. It is also possible to eliminate or at least reduce filters or other protective measures against voltage fluctuations or interference pulses in the high-voltage network, which saves costs.

In one embodiment with the reversible belt tensioner, it is advantageous in terms of voltage fluctuations or glitches that the at least one control unit is electrically connected to the low voltage network and the electric motor of the reversible belt tensioner can be electrically connected exclusively to the high voltage network.

Exemplary embodiments of the present invention will be described by way of example with reference to the drawings.

Showing:

Fig. 1 is a schematic representation of a vehicle with an electric

Drive, a low-voltage network, a high-voltage network, a control unit, a control unit and a reversible

Security component,

Fig. 2 is a schematic representation of the vehicle with a sensor for a

Risk assessment, whereby the control unit can electrically connect the reversible safety component via an extended control unit with the high-voltage network or with the low-voltage network. In Fig. 1, a vehicle 1 is shown with an electric drive E. The electric drive is electrically connected to a high voltage network HV. The vehicle 1 further comprises a reversible safety component RS and a control unit ECU, which is electrically connected to a low-voltage network NV. The control unit ECU can connect the reversible safety component RS to the high-voltage network HV via a control unit S controlled by the control unit ECU. The control unit S is for example an electrical switch or an electrical regulator. In one embodiment, the control unit S is formed by a power transistor. In one embodiment, the ECU is the ECU

Control unit S and the reversible safety component RS, which are shown separately in the figure, at least partially summarized. Thus, in specific embodiments, the control unit ECU and the control unit S or

Control unit, the control unit S and the reversible safety component RS combined in one component.

In an embodiment shown in Fig. 2, the reversible safety component RS is a reversible belt tensioner. If, in this embodiment, a high risk assessment based on an imminent collision of the vehicle with an obstacle is determined by the control unit ECU by means of a sensor I for an environment detection, the control unit ECU connects the reversible belt tensioner via the control unit S 'to the high-voltage network HV. As a result, the reversible belt tensioner quickly wraps webbing with a strong force, pulling a belted occupant into a vehicle seat. The occupant is thus better protected in the event of an imminent collision of the vehicle with the obstacle.

Another example of a high risk assessment is a collision that has already occurred. A successful collision can, for example, by a

Acceleration sensors are detected.

If a severity of the collision is low, alternatively a low one can be used

Risk assessment, whereupon the ECU ECU reversible

Safety component RS connects to the low-voltage network NV.

The ECU evaluates in one embodiment, a buckle sensor, not shown in the drawing, which detects when the occupant has just strapped. If the occupant has strapped in at the start of the journey, the control unit ECU receives a signal from a belt buckle sensor Control unit is interpreted as a low risk assessment because of a possible belt slack. Then it connects the reversible belt tensioner for a short time with the low voltage network NV, whereby the reversible belt tensioner with little force tightens the belt and reduces possible belt slack.

Another example of a low risk assessment is a skidding vehicle or an emergency stop. A flinging vehicle is being used by one

Control unit for a driving stability system detected. A full brake detects a control unit for an anti-lock braking system.

In another example, a low risk assessment illustrated in the examples may represent a high hazard rating, if in the other example a low risk assessment valid there is even lower

Injury risk to the occupant means. Likewise, a high risk assessment presented in the examples may represent a low risk assessment in an alternative example if, in the alternative example, a high risk assessment valid there represents an even greater risk of injury to the occupant.

In further embodiments, the reversible safety component RS is formed by an adjustable seat component, an adjustable window, a sliding roof, an adjustable support surface or by a combination of these components.

In other words, the invention can be represented as follows:

An essential component of an occupant protection system (PRE-SAFE ^® ) acting before an accident is an electric motor-controlled, reversible belt tensioner. A reversible belt tensioner today is able to reduce the belt slack of a belt system from impact. The tightening forces applied thereby amount to approx. 100 N. The

Power supply to the electric motor of the belt tensioner is usually done via a 12 V electrical system.

An essential idea of the invention is to control the reversible belt tensioner via the high voltage and the high-voltage electronics in a hybrid or electric vehicle. Compared with the 12 V electrical system, a high-voltage system has a much higher voltage. Future high-voltage networks will have voltages of approx. 130 V - 400 V. This is accompanied by a higher performance electronic components, for example, the electric motor of a reversible

Belt tensioner.

With the combination of a reversible belt tensioner with a high-voltage system, existing functions with improved properties can be optimized as well as implement new functionalities that have previously failed due to the limited possibilities of a 12 V power supply.

The tightening forces and times with respect to a preventive belt loss reduction can be controlled to a better degree due to the better power development of the electric motor. With the same performance data, the components such as the electric motor can be optimized to the extent that smaller installation spaces for the components are possible. The necessary installation space can be reduced. Tightening forces and temporal

Control can be regulated so far that an active retrieval of pre-displaced or unfavorably positioned occupants is possible. The tensioning forces and the temporal control can be regulated to such an extent that pre-acceleration can be applied to the occupants prior to the impact and thus the occupant load during the impact

actual impact is significantly reduced. The tightening forces and the timing can be regulated to such an extent that the belt tightening can be adapted to the dynamic driving support requirements in a timely manner.

A permanently installed high-voltage network with a voltage greater than 130 V, as occurs only in vehicles with hybrid or electric drive, is used for the activation of a retractor or other PRE-SAFE ^® functions such as a seat adjustment or used an adjustment of a sliding roof. This high-voltage voltage is available permanently and without time limit, for example, for a seat adjustment or to pull the occupant by a slow belt retraction from a deployment area of an airbag. So not only is there a higher energy available for PRE-SAFE ^® functions in the short term, but also permanently. A monitoring mode, if there is enough energy left, is not necessary.

Claims

claims

1 . Vehicle (1) with

an electric drive (E),

- A high voltage network (HV) for the electric drive and

- a low-voltage network (LV) for low-power consumers,

characterized in that

a control unit (ECU) as a low-power consumer a reversible

Safety component (RS) with the high voltage network (HV) can electrically connect.

2. Vehicle (1) according to claim 1,

characterized in that

the high voltage network (HV) has a voltage which is greater than 60V.

3. Vehicle (1) according to claim 1 or 2,

characterized in that

a sensor for a risk assessment regarding a risk of injury to an occupant of the vehicle (1) is evaluated, wherein at a high risk assessment, the control unit (ECU) the reversible

Safety component (RS) connects to the high voltage network (HV), whereas at a low risk assessment, the control unit (ECU) connects the reversible safety component (RS) to the low voltage network (LV).

4. vehicle (1) according to claim 1, 2 or 3,

characterized in that

the reversible safety component (RS) is a reversible belt tensioner, an adjustable seat component, an adjustable window, a sunroof or an adjustable support surface.

5. Vehicle (1) according to claim 4,

characterized in that

the support surface has an energy absorbing property.

6. Vehicle (1) according to one of the preceding claims,

characterized in that

the high voltage network (HV) is designed such that stronger

Voltage fluctuations or stronger interference pulses are permitted than with the low-voltage network (LV).