DE102009019158A1 - Temporarily used mobile measurement system controlling arrangement for passenger car, has current limiting elements designed such that amount of residual current remains below preset exposure limit during breakdown of measuring lines - Google Patents

Abstract

The arrangement has measuring lines (1) located between a measurement system (7) and a measuring point, where the arrangement performs measurements and data acquisition at a high-voltage network. Each measuring line has a current limiting element at its end that is connected with the measuring point. The current limiting elements are designed and dimensioned such that an amount of residual current remains below a predetermined exposure limit during breakdown of the measuring lines or the measurement system.

Description

The The invention relates to an arrangement for intrinsically safe, hazard-free Operation of, in particular temporarily used, mobile Measurement technology under extreme operating conditions, such as in vehicles or similar devices, wherein the measurements and data acquisition be made on a high-voltage network and between metrology and measuring point measuring lines are located, according to the preamble of claim 1

at Hybrid drives of motor vehicles, in particular of passenger cars, In addition to an internal combustion engine is at least one electric drive used. The electric drive has this one from the electrical system the motor vehicle separate power supply. This power supply includes a special electric battery that has a high electrical DC voltage of, for example, provides up to 600 V, as well a power electronics with a corresponding inverter of Electric drive. The drive is equipped with an isolated network, so that the threat of z. B. Service staff reduced becomes. In addition, the correspondingly insulated Network via specially marked cable to when interfering with the vehicle, z. As a repair, the car mechanic make clear where high-voltage cables are located or misplaced were.

at the development and testing of electric or hybrid vehicles Extensive measurement technology, which also includes data loggers, is used. This measurement technology is housed in a suitable location in the vehicle. Usually must be between the respective measuring point and the respective Measuring instrument connecting lines, so-called measuring leads, be installed. This relocation and installation of only temporary is used for appropriate measurement purposes as long as unproblematic, such as measurements on the usual low-voltage electrical system are to be carried out.

are However, measurements on a high-voltage network, such. B. in hybrid or Electric vehicles available, required, may be different Problems with considerable danger occur. If z. B. one of the test leads disconnected or sheared and thus gets Connection to the vehicle chassis, the galvanic isolation of the high-voltage network unilaterally and with low impedance. Then there is a fault the insulation of Gegenpolleitung, occurs a short circuit in the high-voltage network on.

at the probable case that both test leads connected to the Potential of the high-voltage network are connected, disconnected, a short circuit of the high-voltage network takes place via the test leads. Is it z. B. at the measuring side connected lines the high-voltage network around the connections of the high-voltage battery, This can have dramatic effects. Such a high-voltage battery leads DC voltage between z. B. 140V to about 500 V at currents up to 1000 A. A fuse in conventional Art is not readily possible here, d. H. they are usually called Contactors are used. Due to high voltages and currents in conjunction with the line inductances forms in the event of a short circuit at the point of separation an arc, the over has a very high energy and also great Can bridge distances. This results the danger of a vehicle fire or at least further destruction of essential vehicle components.

by virtue of the fact that commonly used Measuring leads a small cross section and thus a higher Resistant, there is a risk that due to the higher Resistance the currents flowing in the event of a fault lie below the shutdown threshold of an electronic fuse. Thus, the aforementioned contactor can not be addressed become.

One Another difficult problem is the potential danger of persons in dealing with the usually only low ones Tension-leading test leads. Since the aforementioned high-voltage circuit does not always disconnect, puts the touch the measuring line, which then galvanically connected to the high-voltage circuit is a life threat. It should be noted that in the DC circuit, the current level is only dangerous if this is not the steady state contact current limit reached.

At the Testing and testing of hybrid and electric vehicles under Real conditions will be laying the necessary test leads often made provisionally. In other words is not fundamental Ensure that the relevant test leads are free from mechanical stress are. It is therefore in mobile use or in plants with strong Vibration and / or moving parts necessary, higher Requirements for the measurement cabling. It is, however unrealistic, here on the fixed in the vehicle system wiring to orient, for the special environmental conditions is designed. Just for cost reasons, but also with Look at the given spatial conditions can not use temporarily installed measuring cables same electrical or mechanical properties as the plant wiring be moved. Added to this is the contacting problem of the cables to suitable for the metrology connectors, the not for the mechanical cable dimensions of an installation cable are designed.

From the DE 10 2006 050 529 A1 a circuit arrangement for insulation and estimation monitoring of the power supply of an electric drive of a vehicle is previously known.

According to the local solution, the insulation of the high-voltage network is monitored by measuring the insulation resistance of the power supply to the vehicle ground. This isolation monitoring is essential not only for safety but also for the reliable disconnection of the battery from the power supply at rest, for example for service purposes. Thus, according to the DE 10 2006 050 529 A1 Monitoring the contactors to disconnect the battery included in the insulation monitoring. This happens because in addition to the feed point of the insulation monitoring voltage and the insulation measuring point, both of which are on the vehicle side after the shooter, a further measuring point is provided, via which the monitoring of the contactor contacts can take place.

In a further embodiment of the DE 10 2006 050 529 A1 a measuring resistor is switched between voltage source and voltage measuring device. The measuring resistor forms with an insulation resistance a voltage divider, which allows the determination of the insulation resistance by a voltage measurement, since, depending on the current insulation resistance, a voltage divider results between the measuring resistor and the unknown insulation resistance. From the measured in the circuit divider ratio of this voltage divider, the insulation resistance can then be determined by calculation.

A Such solution is for stationary applications quite advantageous, but leads in the event of an error to a Disconnecting the high-voltage battery from the high-voltage network. Measurements for narrowing down of fault conditions in a test of a motor vehicle but then can not be performed.

In the method and arrangement for controlling the switching state of a switching connection between the electrical outputs of a fuel cell arranged in a mobile device and an insulated electrical network arranged in the mobile device DE 199 50 008 A1 should be done in critical conditions of the vehicle opening of disconnectors, so that there is always a minimum insulation resistance between the in-vehicle networks, ie the high-voltage network and the usual low-voltage electrical system is available.

Therefor is the insulation resistance between the electrically isolated Network and the mass of the mobile device through a special Pulse measurement determines with the positive and negative pulses over give a known measuring resistor to ground. The impulses call you over the insulation resistance a reference point in the network flowing current, the determined by a voltage drop at the intended measuring resistor is. Such a protective device based on an insulation measurement is permanently installed in the corresponding motor vehicle. For certain measurements and tests relevant to the automotive industry however, in a pre-series or series test it is necessary to disable such usually existing protective devices with the then given danger of endangerment of persons or the vehicle itself, if it is connected by damage Test leads to a short circuit in the high-voltage network comes.

From the DE 102 17 059 B4 is a measured value transmission in high-voltage power supplies previously known. According to the local solution, measuring heads are used which are assigned to the high-voltage devices and by means of which measured values and possibly diagnostic data from the high-voltage devices can be detected and transmitted. These high-voltage device-side measuring heads have an optical waveguide interface. The optical fiber interfaces provide a connection to a local network for the purpose of data transmission and data evaluation. In this case, the high-voltage-relevant measured values are converted into optical signals and transmitted via the fiber-optics without risk. However, it can be seen that in such a measured value transmission additional transducer assemblies are required, on the one hand distort the measurement results and on the other hand lead to higher costs.

From the CH-PS 208575 It is known to measure electrical high voltages in such a way that by means of a voltage divider a precisely determinable fraction is divided and measured. As common means reference is made in this document to ohmic and capacitive voltage divider.

Out The above, it is therefore an object of the invention, a further developed Arrangement for intrinsically safe, hazard-free operation of, especially temporarily used, mobile measurement technology under extreme conditions of use, such as B. in vehicles or specify the same devices, the measurements and the Data acquisition can be done on a high voltage network and between the measuring technology and the measuring point measuring lines are located.

With the arrangement to be created, a hazard to persons when handling the measuring lines should be excluded. In addition, make sure that in case of damage no danger to the actual high-voltage network. The respective measuring lines should be used in a conventional manner and can be installed in the vehicle using the respective possibilities, and without requirements here are equal to and come close to those that corresponds to the permanently installed in the motor vehicle plant cabling.

The Solution of the object of the invention is achieved by an arrangement. for intrinsically safe, non-hazardous operation of, in particular temporarily used, mobile measurement technology according to the feature combination according to claim 1 and with a measuring line according to definition according to claim 11.

The Subclaims make at least appropriate Embodiments and developments of the invention.

It is therefore from an arrangement for intrinsically safe, hazard-free Operation of, in particular temporarily used, mobile Measurement technology under extreme operating conditions, such. B. in vehicles or the like facilities are assumed, the measurements and the data acquisition on a high-voltage network, z. B. in the range between 180 V to 800 V, be made and continue between the measurement technology and the measuring point corresponding measuring lines are located.

According to the invention the respective measuring line at its connected to the measuring point or connectable, d. H. So high-voltage end with at least provided a current limiting element, which is safe to touch is executed.

The At least one current limiting element is dimensioned such that the magnitude of the fault current in case of damage the remaining measuring line or the connected measuring technology remains below specified hazard limits.

The At least one current limiting element may in one embodiment be integrated into the respective measuring line end of the invention or and close to the high-voltage side connection or terminal point are located. In this case, the at least one current limiting element be enveloped by an insulating potting material. The potting material then takes on a first side of the measuring line and encloses this tight. On the other, preferably opposite End of the potting z. B. a cable lug or a suitable Include connecting element to the high-voltage connection.

The Current limiting element can further ausgestaltend a part form the voltage divider of the actual measurement technology and accordingly be dimensioned so that no Meßwertverfälschungen or other impairment of the measured value results occur.

at an embodiment of the invention, the larger Part of the voltage divider at the measuring point and the smaller part be formed of the voltage divider at the measuring input. Will on the Based on this conception of greater resistance of the divider at the cable end, d. H. at the measuring point, and the smaller one Resistance located at the fair entrance, the fair entrance sets one Current input. The advantage of a current input with virtual Zero point is that there are no voltages on the test lead and thus no recharging of the cable capacity must be made. Thus, the cable capacity does not limit the signal frequency response, thereby also a use in measurements with a high sequence of evaluated Drive signals is possible.

Prefers is the current limiting element as a resistor, semiconductor or a combination of these trained.

The respective measuring line has at its with the high-voltage network end to be connected via suitable connection means, which correspond to the respective high voltage application or adapted are. The high-voltage connection side is made recognizable as such, and for example by a special color design.

The can be connected to the high-voltage network side end of the measuring line moreover, have a certain coding and / or over have special haptic features. All this carries helping to prevent accidental misconnection especially under hard measuring conditions when using the measuring technology as part of a test drive under difficult conditions such as z. Cold or dark.

The Test leads are preferably multi-pole and twisted executable.

The respective measuring line can in a further embodiment on or near the current limiting element via have a signaling device to the correct Mode of action with regard to the current limit in the case of measurement or a To indicate fault. Conceivable here is the integration of a light-emitting diode in the above-mentioned potting area.

The Test leads are outside of the section with the at least a current limiting element as usual standard laboratory measuring cable can be formed.

According to the invention beyond that, the application of the measuring line presented here in an arrangement for intrinsically safe, safe operation of, in particular temporarily used, mobile measurement technology under extreme conditions of use, such as B. in vehicles or like devices, the measurements and the data acquisition be made on a high-voltage network and between metrology and measuring point measuring lines are necessary.

The Invention will be described below with reference to an embodiment and explained in more detail with the aid of figures become.

in this connection demonstrate:

1 a typical representation of a situation of the connection of conventional measuring leads for operating a measuring device, wherein the connection points are located on the high-voltage network;

2 a representation similar to that after 1 , However, already using the measuring lines according to the invention with integrated current limiting element on the high-voltage side terminal end and

3 a basic embodiment of an end of a measuring line, which is connectable via a cable lug with a high-voltage terminal for corresponding measurement purposes.

As shown 1 shows how standard measurement cables from the laboratory sector in vehicle test vehicles have been used so far. This standard measuring cable 1 as far as possible z. B. routed by cable ties at a suitable location and fixed. In the case shown 1 become the measuring cables or test leads 1 with high-voltage connections 2 connected. These high-voltage connections can z. B. the connections of the output of a frequency converter 3 correspond to the power electronics. The frequency converter 3 stands over high-voltage connection cable 4 with a high-voltage battery 5 in connection.

If there is a short circuit 6 in the field of measuring cables 1 or a short circuit or damage in the measuring technique 7 Due to the high voltages and currents together with the line inductances at the short-circuit or cut-off point, an arc is formed which can also bridge larger distances. This results in the risk of vehicle fire.

Another problem is the risk to persons when handling the test leads. Since the battery circuit can not always be disconnected for various reasons, a life-threatening situation may result if the high-voltage circuit is touched via the test leads 1 he follows.

However, according to the invention come special measuring cables or test leads 1 used, as in the 2 shown, the danger described above no longer exists.

These measuring cables or test leads according to the invention 1 have at their with the measuring point 2 connected or connectable end at least one current limiting element 8th on.

This current limiting element 8th is for example a resistance of about 500 kΩ. The current limiting element is finger-proof (see 3 ) and dimensioned so that the height of the fault current in case of damage to the measuring line 1 or the connected measuring technology 7 remains below specified hazard limits.

According to the illustrated embodiment, the voltage divider present on the measuring devices 9 split up and spatially separated.

One Part of the divider chain is virtually in the terminals direction contacting of the test object. The values for these current limiting resistors are chosen so that the height of the fault current if the measuring cable is damaged along its route to the meter below the mentioned hazard limit remains.

at an intended resistance R of 500 kΩ and a maximum Working voltage of Umax = 1000 V results in a maximum fault current of 2 mA. When in contact with DC, a value of 2 mA than below the limit of perceptibility. Such a thing Limited current can also lead to no problematic arcing.

As shown 3 is one end of the power line 1 in a casting 10 added. The casting 10 can still from a casting sleeve 11 be enclosed or even formed like a sleeve.

Inside the potting material 10 is located as a current limiting element 8th a protective resistor. This protective resistance is related to the metallic soul 12 the measuring line 1 in connection. In addition, there is another connection of the protective resistor 8th with a conductive end of a part in the potting 10 embedded cable lug 13 , Instead of a cable lug 13 as a connection means can also according to the respective high-voltage application, a suitable connection means be provided.

The end of the measuring line to be connected to the high-voltage network 1 , in particular the potting or Vergusshüle may or may have a special color coding, a mechanical coding and / or typical haptic features to ensure a safe connection and a risk-free operation of the measurement even under problematic operating conditions.

1

Leads or measuring line

2

High-voltage connection

3

frequency converter

4

High-voltage cable

5

High-voltage battery

6

short circuit

7

measuring technology

8th

Current limiting element

9

voltage divider

10

grouting

11

Vergusshülse

12

metallic or conductive soul

13

lug

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 102006050529 A1 [0009, 0010, 0011]
• DE 19950008 A1 [0013]
• - DE 10217059 B4 [0015]
• - CH 208575 [0016]

Claims (11)

Arrangement for the intrinsically safe, danger-free operation of, in particular temporarily used, mobile measurement technology under extreme operating conditions, such as in vehicles or similar devices, wherein the measurements and the data acquisition are performed on a high-voltage network and are located between measurement and measuring point measuring lines, characterized in that respective measuring line at its connected to the measuring point or connectable end has at least one current limiting element, which is carried out safe to touch and dimensioned so that the height of the fault current remains in case of damage to the measuring line or the connected measurement below predetermined hazard limits. Arrangement according to claim 1, characterized that the at least one current limiting element in the respective Measuring line end is integrated and close to the high-voltage side Connection or. Clamp is located. Arrangement according to claim 1 or 2, characterized that the at least one current limiting element of an insulating Encapsulated casting material. Arrangement according to one of the preceding claims, characterized in that the current limiting element is a part the voltage divider of the measurement forms, with the smaller Part of the voltage divider at the measuring input and the larger one Part of the voltage divider is formed at the measuring point. Arrangement according to one of the preceding claims, characterized in that the current limiting element is a resistor, a semiconductor or a combination of these aforementioned means. Arrangement according to one of the preceding claims, characterized in that the respective measuring line at its to be connected to the high-voltage network end via connection means has adapted which of the respective Hochvoltapplikaton and are recognizable as such. Arrangement according to claim 6, characterized that to be connected to the high-voltage network end of the measuring line a special color coding, mechanical coding and / or haptic Features. Arrangement according to one of the preceding claims, characterized in that the measuring lines multipolar and twisted are executed. Arrangement according to one of the preceding claims, characterized in that the respective measuring line on or in near the current limiting element via a Signaling device features the correct mode of action in terms of current limitation in case of measurement or a fault display. Arrangement according to one of the preceding claims, characterized in that the measuring leads outside of the section with current limiting element as usual Standard laboratory measuring cables are formed. Measuring line, which at its with the measuring point connectable end has at least one current limiting element, which is safe to touch and dimensioned is that the amount of fault current in case of damage the measuring line or the connectable measuring technology below specified hazard limits remains for use in an arrangement for intrinsically safe, non-hazardous Operation of, in particular temporarily used, mobile Measurement technology under extreme operating conditions such as in vehicles or similar devices, wherein the measurements and data acquisition be made on a high voltage network.