Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
  • B60R21/00—Arrangements or fittings on vehicles for protecting or preventing injuries to occupants or pedestrians in case of accidents or other traffic risks
  • B60R21/01—Electrical circuits for triggering passive safety arrangements, e.g. airbags, safety belt tighteners, in case of vehicle accidents or impending vehicle accidents
  • B60R21/017—Electrical circuits for triggering passive safety arrangements, e.g. airbags, safety belt tighteners, in case of vehicle accidents or impending vehicle accidents including arrangements for providing electric power to safety arrangements or their actuating means, e.g. to pyrotechnic fuses or electro-mechanic valves
  • B60R21/0173—Diagnostic or recording means therefor
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/005—Testing of electric installations on transport means
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R17/00—Measuring arrangements involving comparison with a reference value, e.g. bridge
  • G01R17/10—AC or DC measuring bridges
  • G01R17/105—AC or DC measuring bridges for measuring impedance or resistance

Definitions

• the present invention relates to a method for determining an internal resistance of a supply network for supplying energy to a
• Control device or a corresponding device and to a corresponding computer program product For the safe supply of an airbag control unit, a highly reliable ground connection to the vehicle chassis is used.
• the ECU side usually gets the chassis ground provided via redundant electrical connections (eg, bolted connections,
• Plug connections in combination with a press-in or solder connection to the circuit board is in use.
• the positive supply line (KL15R, KL15, UBAT ... etc.) is usually singular or redundant via the airbag connection cable through one or more connectors in combination with a press-fit or
• Supply line interrupted. This is done by constant monitoring of the supply voltage with fault detection in under- and overvoltage, as well as measures in the service which provide a control of ground connections to the vehicle chassis.
• Charging unit includes, which by means of a primary interface with the
• Personal protection device can be understood as a resistor, which is composed of several partial resistors. These partial resistances are determined by the generator and / or battery the contact resistances of all used contacting units in the supply circuit and the
• Transport resistance (Cu lines, vehicle chassis) formed in the supply circuit.
• a supply network of the personal protection device can be understood as meaning an electrical network which is designed to supply this personal protection device with electrical operating energy.
• the overall supply network can also have networks with other electrical consumers at different locations in the vehicle.
• a charging unit for example, a current regulator or
• Voltage regulator understood to be an energy buffer with electrical energy from the supply network in the control unit
• Personal protection device charges. Under a personal protection device, a system of control unit / s which in conjunction with internal and external sensors in the case of a defined event z. Eg crash
• protective devices devices are understood to be activated in an appropriate manner in order to minimize or avoid injury to a person either in the vehicle or outside a vehicle.
• the intermediate energy storage can be understood to mean an electrical storage element, such as a capacitor or rechargeable battery, which is supplied with electrical energy from the supply network and which is in the
• interrupted supply self-sufficiency
• the individual passenger protection elements airbag, belt tensioner;
• an interface of the charging unit for outputting electrical power and energy to the
• Energy buffer can be understood. Under an impression of a charging current value, the setting of a current flow with a certain value (which also includes the value zero amps) at the
• Change in load in an energy withdrawal from the supply network can be effected. About this change in load can then draw a conclusion on the internal resistance of the supply network, for example, allows an indication of a poor electrical connection in terminals of connecting cables.
• the approach presented here has the advantage that by an advantageous combination of mostly existing or measurable parameters without the requirement of an additional sensor there is a possibility to check the quality of an electrical connection in connection lines of the charging unit or equipped with the charging unit personal protection device. From the specific quality of the electrical connection can then
• an error message may be issued to the user of the vehicle for a workshop visit to motivate to replace or clean up this fault, such as a corroded connection.
• Charging unit which is primarily determined current change in the transition from a first to a second secondary charging current value.
• Embodiment of the present invention allows the determination of the internal resistance of the supply network on the basis of only a very few measured parameters. In this way, the probability of a faulty internal resistance based on a measurement error is largely reduced.
• Step of determining, while impressing a second secondary charging current value, the voltage at the primary interface is low-pass filtered.
• Such an embodiment of the present invention offers the advantage that short-term fluctuations of the current and / or the voltage remain insignificant during the measurement, so that the probability of a faulty internal resistance of the supply network is significantly reduced.
• the second charging current value in comparison to the first charging current value can be selected such that
• Such an embodiment of the present invention offers the advantage of a possibility of particularly precise determination of the internal resistance of the supply network.
• the second Charging current in relation to the first charge current value can be achieved that at the primary interface, the respective current change and / or the respective voltage change (in the fault case) are sufficiently large, so that even small values of the internal resistance of the supply network can be resolved with sufficient accuracy.
• the specification of the second secondary charging current value can take place after a predetermined time period for specifying the first secondary charging current value.
• the second charge current value within a period of 1
• Internal resistance is determined using a look-up table and / or wherein in a step of detecting the current and or
• Lookup table to be determined may be applied to the execution of numerically or
• the steps of detecting during the specification of a first secondary current, the detection during the specification of a second secondary current value can be performed several times in succession and the internal resistance calculation after each sub-step, which finally from the stored
• a mathematical algorithm averaging, rejection of outliers, etc.
• Such an embodiment of the present invention has the advantage that in determining the internal resistance of the supply network random interference or special phenomena, for example, after long vehicle downtime, can be excluded as possible.
• Control device of this device the method comprising the following steps:
• Such an embodiment of the present invention offers the advantage of early warning when the internal resistance meets a certain criterion or a predetermined relationship to a resistance threshold
• Personal protection device such. B. reduced robustness in the case of
• Ignition circuit short circuits due to "Ground Shift” or reduced performance of the redundant activation of personal protection devices (devices such as airbags, belt tensioners, etc.) from the supply network can no longer be performed correctly.
• the electronic control unit of this device may comprise a charging unit which by means of a primary interface with the supply network and by means of a secondary interface with the energy buffer for temporarily storing energy for the self-sufficiency of the
• Personal protection device z. B. in a crash and to provide the
• Control unit be connected from the supply network.
• the device comprises the following features:
• the approach presented here thus also provides a device which is designed to carry out or implement the steps of a variant of a method presented here in corresponding devices. Also by this embodiment of the invention in the form of a device, the object underlying the invention can be solved quickly and efficiently.
• a device can be understood as meaning an electrical device (electronic control device of a personal protection device) which Sensor signals processed and depending on control and / or
• the device may have an interface, which may be formed in hardware and / or software.
• the interfaces may be part of a so-called system ASIC, which includes various functions of the device.
• the interfaces are their own integrated circuits or at least partially consist of discrete components.
• the interfaces may be software modules that are present, for example, on a microcontroller in addition to other software modules.
• An advantage is also a computer program product with program code, which on a machine-readable carrier such as a semiconductor memory, a
• Hard disk space or an optical storage can be stored and used to carry out the method according to one of the embodiments described above, when the program product is executed on a computer or a device.
• the present invention thus provides according to an embodiment, a computer program product with program code for performing the method according to a variant presented here, when the program product on a
• Fig. 1 is a circuit diagram of an apparatus for use in a
• Fig. 2 is a circuit diagram of an apparatus for use in a
• Fig. 3 is a diagram of a time course of voltages or currents as a waveform of the vehicle electrical system internal resistance measurement
• 4 is a circuit diagram of a power supply circuit for use in another embodiment of the present invention.
• Fig. 5 is a circuit diagram of a suitable charging current source for the
• One aspect of the invention is to provide a way to create by detecting, for example, a too high supply internal resistance of a vehicle electrical system (subnetwork) (as a network of a vehicle, here the safety-related supply network of a personal protection device) to force a targeted service or maintenance stay in a workshop and to exclude a security-relevant influence,
• a vehicle electrical system subnetwork
• a network of a vehicle here the safety-related supply network of a personal protection device
• airbag systems can dispense with redundant supply connection, in particular the ground.
• redundant supply connection in particular the ground.
• This brings advantages for the housing construction (eg solid plastic or by using the ground connection via the connector in carbon chassis etc.). It is also recognized in good time whether back-up structures for retaining agent activation (firing) from the vehicle battery (not the energy reserve) would be effective.
• FIG. 1 shows an exemplary circuit diagram of a supply network 100 of a vehicle 105, which is provided with a charging unit 110 of a vehicle
• the charging unit 1 10 (which is designed here as part of an airbag (control units) - supply ASIC) is connected via a primary interface 135 to the connection points A and B to the supply network 100. Furthermore, the charging unit 1 10 by means of the secondary interface 140 with the
• Charging unit 1 10 is arranged on a common PCB PCB.
• This printed circuit board PCB may be disposed on a floor panel 145.
• Supply network 100 has a generator G, a generator internal resistance RG and a generator controller GR, which charge a battery BAT (for example, a battery as a vehicle battery) to a certain voltage.
• a battery BAT for example, a battery as a vehicle battery
• Fig. 1 shows an overview of which electrical system internal resistance is to be determined with the approach presented here. It is the sum of all resistances between the positive terminal A and the ground terminal B of the control unit or the charging unit 1 10 determined. In other words, the internal resistance of the supply network 100 is determined at the primary interface 135. This internal resistance comprises the sum of all resistances between the points A and B. In particular, the internal resistance to be determined along the measurement path 150 thus includes the
• resistors R1: ⁇ of all R's on PCB from the plug of the control unit plus supply to airbag (control unit) circuit supply (eg track resistance; ..)
• R6 / RG (R6 is effective) Internal resistance of the vehicle battery (in the case of engine off, generator standstill) or RG Internal resistance of the generator in case of engine on, generator running)
• R7 Contact resistance battery / generator ground connection to chassis
• R8 Internal chassis resistance
• R9 Contact resistance of vehicle chassis to control unit base plate
• R10 ⁇ of all contact resistances Controller base plate to PCB ground connection
• R1 1 ⁇ of all R's from the PCB ground terminal to the ground supply of the supply circuit (eg track, resistor ..; ..)
• Fig. 2 shows a circuit diagram of a power supply circuit 200 with a charging unit 110 for use in an embodiment of the present invention.
• the charging unit 110 is connected via the secondary interface 140 to the energy buffer 120, which can also be designated by the abbreviation ER.
• the primary interface 135 is shown on the left in FIG.
• the pure voltage measurement (UB) is carried out via the low-pass filter Mux + ADC. If, in addition to the pure voltage measurement UB, a primary current measurement is necessary in the case of complex relationships between primary and secondary current that can not be laid down by tables, a shunt is inserted into the primary supply line and another voltage measurement channel via a primary current measurement second identical low-pass led to a second mux channel of the ADC.
• the power supply circuit 200 comprises a plurality of units, such as a controllable down converter (Dn Converter) for generating the system voltage VA S, necessary for the sensor interface supply according to the PSI standard, a controllable up-converter Up
• VUP 20V ... 50V
• A_Sensor a microcontroller ⁇ C
• SPI interface SPI an SPI interface SPI.
• the power supply circuits have an efficiency of generally ⁇ on z. B. (i "
• the charging unit 1 10 via an ASIC internal bus 210 to the other ASIC function blocks such.
• the central multiplexer + ADC are connected to the SPI interface (Serial Peripheral Interface) 245 connected.
• the electrical energy supplied by the supply network 100 can be supplied via the polarity reversal protection diode D1 to the boost converter and its external components, e.g. L1 and D2 supply the charging unit 1 10 and in parallel the VAS down converter. Similarly, from the supply network, a redundant
• the terminal UB of the control unit with the power supply 200 detected via a low-pass filter 220, for example by a resistance voltage divider with a capacitance between a connection point A and a ground potential B formed (integrated or partially integrated in the airbag control units system ASIC) the supply voltage UB via the
• a differential voltage measurement can also be carried out via further input measuring channels of the multiplexer via a low-impedance shunt, which is connected in series in the UBA ZP line before or after the diode D1, and thus the supply current can be determined directly from the differential voltage measurement. From the measurement of
• the power or the energy consumption can be determined directly by integration over time in the C. If the optional current measurement is missing, the change in the primary current consumption can be determined from the change in the current output of the charging unit 1 10 via the efficiency of the up-converter ⁇ _up, provided that
• ECU design ensures that the power requirement through the VAS buck converter remains constant. With this, the change of the line input from the supply network can finally be determined.
• the charging unit 110 can be programmed or controlled, for example in such a way that different charging current values (IER) can be impressed on the secondary interface 140 at different times. This means that the charging unit 1 10 is controlled such that over the
• Energy buffer 120 flow and thus the charging speed increases or decreases.
• the programming or control of this power charging behavior at the secondary interface 140 may be done over several
• Programming terminals 250 which are connected in parallel with I / Os of the ⁇ , or via ⁇ SPI commands, which are transmitted to the charging unit or any other type of command transmission of the ⁇ to the charging unit.
• Different charging current values IER of the secondary interface are affected by the fact that different currents IBAT and / or voltages UBAT (observed via the DC bus) also occur at the primary interface in the UB supply line to D1
• the difference of the input currents 11, 12 should be chosen so large that relevant resistances (0.5 ... 1 .5) ⁇ are resolvable.
• this is suitable to filter.
• filtering of the fault over multiple starts is appropriate to eliminate random noise or extraneous phenomena after long vehicle downtime.
• the internal resistance of the supply network can be detected very low.
• airbag controllers which are controlled by a boost converter to produce a regulated output voltage VUP (20 ... 50) V e.g. 33V from the reverse-voltage protected vehicle voltage VZP (5 ... 20) V and, on the one hand, via a down converter a regulated output voltage VAS (6 ... 8) V e.g. Provide 6.7V, for further low-loss generation of the necessary
• the energy reserve charge current regulator i.e., the charging unit 110
• the energy reserve charge current regulator is configured so that at least two different charging current control values can be selected for shutdown (zero charge current value).
• a value is used for the normal charge of the energy reserve 120 or ER accordingly
• a second (for example, larger) value is used in addition to the short-term secondary (faster) energy reserve charge, the primary increase of the airbag supply current to set the current value 12 for the internal resistance measurement.
• the control current value of the second (for example, larger) value is used in addition to the short-term secondary (faster) energy reserve charge, the primary increase of the airbag supply current to set the current value 12 for the internal resistance measurement.
• Charge current controller 1 10 programmed in a certain step size and thus optimally tuned to the various requirements.
• VUP boost converter output voltage
• VZP boost converter input voltage
• n, _up is the efficiency of the converter. In a first approximation, this is constant. But for real systems he is from the
• Input voltages VZP 5V ... 8V noticeable, for larger voltages VZP> 8V it becomes smaller and smaller.
• the relationship A) can be further detailed and approximated very well to well with a classification of a maximum of 8 VZP ranges up to a minimum of 3 VZP ranges:
• a 10-bit ADC i.e., the ADC of Fig. 2
• ADC of Fig. 2 the ADC of Fig. 2
• Internal resistance R determine. In order to selectively use an increase in the supply current of the airbag control unit or of the power supply circuit 200 for measurement purposes, it is most sensible and cost-effective for the overall system to do so by using the energy reserve charging current circuit 110. As a result, an already existing device 110 is only improved (cost) and the increased energy consumption serves the purpose of the energy reserve charge.
• the up-converter relationship A) applied to the overall control device leads to the following relationship:
• p2 is the sum of all consumptions from UBAT or VZP which are primarily required by the auxiliary functions control unit (eg divider transverse currents of measuring device 135, reference currents, communication currents through pull-up resistors to UBAT, VZP etc.). In general, this performance is small, in particular, your fluctuation can be neglected.
• the vehicle electrical system voltage z. B. UBAT 16.5V
• the boost converter output voltage VUP 33V
• VZP reverse polarity protected voltage
• Ud 0.5V lower than UBAT. from B1) and A2) -> B2)
• IER_TEST 5IBAT x [n_up x (UBAT-Ud)] / VUP
• Is UBAT (t7) UBAT (t3) +/- (0 ... 2LSB)? if yes -> (J), if no (N)
• Reading the internal resistance error limit from a data read-only memory (FLASH, EEPROM etc.), eg 1 ⁇ :
• the output voltage of the boost converter may be measured (usually unchangeable, since regulated). Thereafter, the battery voltage UBAT is measured at time t3 at low input current IBAT (t3).
• the ER charging current regulator is set to a high value (programmed, etc.).
• B. IER (t4) 120mA. This increases the supply current of the control unit defines strongly.
• the battery voltage on the other hand, decreases with finite internal resistance.
• UBAT is measured.
• the diagram shows an example of the internal electrical system resistance measurement with the following values: VER (tO) ⁇ 25 V measured.
• VER (tO) ⁇ 25 V measured.
• VAS deceleration converter needed.
• the external sensors are not active yet.
• 60mA is taken from VUP to charge the ER here.
• UBAT (tO) 12V
• IBAT (tO) 12V
• IER (t1) ER charging current is switched from 60mA to 0mA.
• IER (t4) ER_charging current is switched from 0mA to 120mA as the second charging current value.
• IER (t5) 120mA test current for vehicle electrical system internal resistance R.
• UBAT (T5) 1 1, 8 V will then
• Fig. 4 shows a circuit diagram of a power supply circuit 200 for use in another embodiment of the present invention.
• the up-converter (down-converter) is followed by a down converter Dn-converter with output terminal VAS to the control unit supply (external sensor + internal supply).
• the boost converter also downstream of a charging unit for the energy reserve ER.
• This charging unit 1 10 can either via parallel
• Control lines 250 or via a serial interface 245 are controlled.
• FIGS. 2 and 4 the area is particularly marked in an airbag control unit, which by suitable adaptation also calls for
• the charge current regulator 110 should be programmable or controllable to provide a new control current level capable of causing a current change sufficient on the primary (UBAT) side for internal resistance measurement R.
• low-pass filter 220 to an ADC (primary interface 135) to detect the supply voltage change due to the supply current change due to the electrical system internal resistance R supply voltage change (620).
• FIG. 5 shows a more detailed circuit diagram of a suitable ER charging current source or a power supply circuit 200.
• a serial interface eg SPI
• a parallel interface the airbag system controller is in the Able to specify different control current levels. These serve to load the energy reserve ER.
• controller 110 is usually switched on or off only via control lines.
• Internal resistance measurement R are to specify significantly higher charging control current values. As a rule, these can not be used to fully charge the ER (current consumption, power dissipation too high). Due to more control cables or full programmability becomes to
• Internal resistance measurement R of the vehicle electrical system 100 of the ER charging control current set to high values for a limited time. This is done according to the illustration of FIG. 5 by changing the regulator reference voltage. higher
• the difference of the input currents 11, 12 should be chosen so large that relevant resistances (0.5 ... 1 .5) ⁇ are resolvable.
• Airbag control units which via a boost converter for generating a regulated output voltage VUP (20 ... 50) V eg 33V from the
• V z. B. 6.7V for further low-loss generation of the necessary system voltages (5V, 3.3V, 1.2V ... etc ..) and external sensor supply and on the other via an ON / OFF-switchable energy reserve charging current regulator for charging the ER on have about VUP form the known solution basis.
• FIG. 6 shows a flow chart of an embodiment of a method 600 of a method for determining an internal resistance of a
• the method includes a step of impressing 610 a first one
• Charge current value at the secondary interface 140 Further includes the
• the method comprises a step of detecting 620 or determining a current and / or a voltage at the primary interface (UB coupling to the supply unit of the control unit) during the impressing 610 of a first secondary charging current at the secondary coupling 140
• the method 600 includes a step 630 of impressing a second of the first different secondary charging current to the secondary coupling 140 to the energy reserve (ER) and a step 640 of the re-capture or
• FIG. 6 is a flow chart of an embodiment of a method 600 of a method for determining a
• the personal protection device includes a charging unit, which by means of a primary interface with the supply network and by means of a
• the method 600 includes a step 610 of impressing a first charge current value on the secondary interface. Furthermore, the method comprises a step 620 of detecting a first current and / or a first current
• the method 600 also includes a step 630 of impressing a second charging current value, which is different from the first charging current value, at the secondary interface. Furthermore, the method 600 includes a step 640 of determining a second current and / or a second voltage at the primary interface during imprinting. Finally, the method 600 includes a step 650 of determining the internal resistance of the supply network using the first current and the second current and / or the first voltage and the second voltage.
• an exemplary embodiment includes a "and / or" link between a first feature and a second feature, this is to be read such that the
• Embodiment according to an embodiment both the first feature as well as the second feature and according to another embodiment, either only the first feature or only the second feature.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Charge And Discharge Circuits For Batteries Or The Like (AREA)
• Air Bags (AREA)
• Testing Electric Properties And Detecting Electric Faults (AREA)
• Secondary Cells (AREA)

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• 2014
  • 2014-04-15 DE DE102014207171.2A patent/DE102014207171A1/de not_active Withdrawn
• 2015
  • 2015-03-26 WO PCT/EP2015/056605 patent/WO2015158521A1/de not_active Ceased
  • 2015-03-26 JP JP2016562837A patent/JP6548666B2/ja active Active
  • 2015-03-26 US US15/301,742 patent/US10286868B2/en active Active
  • 2015-03-26 CN CN201580020034.XA patent/CN106233149B/zh active Active
  • 2015-03-26 KR KR1020167031775A patent/KR102312590B1/ko active Active
  • 2015-03-26 EP EP15713698.7A patent/EP3132271B1/de active Active

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