Apparatus and method for monitoring electrical safety interlocks

Abstract

The invention relates to a device and a method for monitoring an electrical safety interlock, the invention being based on the task of providing a solution by which affordable and robust monitoring in a safety interlock device is facilitated and the overall complexity of the circuit system is reduced. The task is solved in terms of the device by a separate circuit (6a, 6b) connected to a signal generation and evaluation unit (9) that generates a continuous and discrete-valued signal (11). In terms of the method, the task is solved by performing monitoring of the circuit using a continuous and discrete-valued signal (11), which is provided by the signal generation and evaluation unit (9) and which is evaluated by the signal generation and evaluation unit (9) via transmission of the circuit.

Description

Technical Field

[0001] The invention relates to a device for monitoring electrical safety interlocks, the device comprising a connector with high voltage wires, wherein an interlock bridge is arranged in the connector and is connected to a first part of a separate circuit and a second part of the separate circuit when the connector is correctly connected to a high voltage component.

[0002] The invention also relates to a method for monitoring an electrical safety interlock, in which method a monitoring of an electrical circuit of a safety interlock device is performed, wherein the circuit is provided with a first part of a separate circuit and a second part of a separate circuit and an interlock bridge arranged in a connector.

[0003] In particular, the present invention relates to electrical safety interlocks used in vehicles that operate electrical components using a DC voltage of 60 V or higher. This is the case, for example, where an inverter is used in the vehicle, for example, which is required in order to convert the DC voltage into an AC voltage.

[0004] The invention also relates to a safety interlock for use in an electric vehicle or a vehicle with a so-called hybrid drive. Background Art

[0005] When inverters are used to drive electric motors at high voltages, in particular in vehicles with an on-board voltage of more than 60 V, these are often also referred to as high voltage (HV) applications in the motor vehicle sector. An inverter for an electrically driven refrigerant compressor in a vehicle is an example of such a high voltage application or high voltage component.

[0006] In this case, the inverter as a high voltage component provides an AC voltage required for operating the electric motor of the refrigerant compressor according to a DC voltage equal to or greater than 60 V, for example, and may also include a plurality of phases.

[0007] Safety interlocks are used, for example, in electric vehicles with high voltage applications (greater than 60 VDC). The task of such safety interlocks is to monitor the operating state of high voltage circuits connected to high voltage components, and in particular to check whether all connectors or plug-in connections of such high voltage circuits have been safely plugged in / connected.

[0008] For example, before a high voltage (greater than 60 VDC) can be applied, a safe connection of a connector or plug-in connection is checked in a high voltage circuit of an electric refrigerant compressor. This check can be performed both for a single connector or plug-in connection and for multiple connectors or plug-in connections.

[0009] Various solutions for such safety interlocks are known from the prior art.

[0010] One version of such a safety interlock according to the prior art envisages the use of an interlocking bridge in a connector or plug-in connection via which the high voltage is supplied to the high-voltage component.

[0011] When the connector or plug-in connection is correctly connected, the individual circuit is closed using such an interlocking bridge. The closing of the individual circuit, which is isolated or electrically insulated from the high-voltage circuit for monitoring purposes, is detected using a suitable evaluation unit of the safety interlock and the high voltage is then applied.

[0012] Such an evaluation unit for detecting a safely closed high-voltage circuit by monitoring the individual circuits is arranged, for example, in an electronic component of a vehicle, ie in the vehicle electronics.

[0013] In different versions of such safety interlocks according to the prior art, the checking of such a separate circuit provided for monitoring purposes extends across a plurality of connectors or plug-in connections, each of which presents a corresponding interlocking bridge. Only when the separate circuit (interlocking loop) extending across all interlocking bridges of all connectors or plug-in connectors is closed, a high voltage is applied to the corresponding high-voltage component, such as an inverter.

[0014] One disadvantage of this prior art lies in the fact that a short circuit can occur in one of the connectors / plug-in connections or in a separate circuit used for monitoring purposes, wherein the evaluation unit can interpret this state as a correctly closed connection.

[0015] In order to avoid such incorrect detections, further methods are known from the prior art which aim to avoid erroneous detections or monitoring of high-voltage circuits.

[0016] An electrical energy source for motor vehicles is known from US Pat. No. 7,557,460 B2. The task is to detect the disconnected state of the interlock line and, if necessary, to deactivate the contactor in order to achieve safety when applying the operating voltage.

[0017] It is therefore contemplated that the interlock circuit comprises a current output circuit that outputs a detectable current to the interlock line via a diode. It is also contemplated that a first current detection subcircuit connected to the current output circuit via the interlock line and the diode, a second current detection subcircuit connected to a connection point operatively arranged between the current output circuit and the diode, and an evaluation circuit.

[0018] If a detectable current is detected in the second current detection subcircuit of the interlock circuit but not in the first current detection subcircuit, the evaluation circuit determines that the interlock line is in a disconnected state and thus deactivates the contactor, thereby interrupting the application of the high voltage.

[0019] US Pat. No. 10,139,443 B2 describes a switching device and a method for determining the state of an interlock circuit. The object to be achieved is to achieve reliable protection of people and animals from the dangers associated with high-voltage components in vehicles.

[0020] To achieve this object, a switchgear is provided for determining the state of an electrical interlock conductor loop, in particular a contact protection circuit of a vehicle, in particular a hybrid vehicle or a fully electric vehicle, wherein the interlock conductor loop itself is provided for monitoring at least one high-voltage component of the vehicle.

[0021] However, these known solutions for improving the functionality of the safety interlock have the disadvantage that they require complex circuit arrangements, in particular for measuring analog variables, which increases their manufacturing costs. In the system according to US Pat. No. 7,557,460 B2, even two current detection subcircuits are required.

[0022] In addition, it is also necessary to measure analog variables with low amplitude, such as voltage and / or current, in such safety interlocks. However, due to the low amplitude of the variables, such measurements are highly sensitive to disturbances, which limits their functionality and stability.

[0023] In the event of a fault, no diagnosis can be generated as to which fault has occurred and in which part.

[0024] Therefore, there exists a need for improved apparatus and improved methods for monitoring electrical safety interlocks, particularly in vehicles. Summary of the invention

[0025] Technical issues

[0026] An object of the present invention is to provide an apparatus and method for monitoring electrical safety interlocks, by which affordable and robust monitoring of safety interlocks is facilitated and the overall complexity of the circuit system is reduced.

[0027] Solution to the problem

[0028] This object is achieved by the subject matter presenting the features of patent claim 1 according to the independent patent claim. Further embodiments are provided in the dependent patent claims.

[0029] The object is also achieved by a method which exhibits the features of patent claim 5 according to the independent patent claim. Further embodiments are provided in the dependent patent claims.

[0030] In order to monitor the safe operation of high-voltage electrical circuits in vehicles, it is envisaged that connectors or plug-in connections such as those known from the prior art are provided with an interlocking bridge.

[0031] It is also envisaged to use suitable means to generate a signal in which the signal level changes in a defined manner over time and is transmitted via a line arranged for a separate circuit, in particular a connector or an interlocking bridge of a plug-in connection. Such a signal can be, for example, a bit pattern that is easy to generate. Alternative signals with more than two switching states can also be used.

[0032] For example, a microcontroller or microprocessor can be used as such a means for generating a bit pattern, for example a digital bit pattern. Many components of a high voltage component, such as an inverter for a refrigerant compressor, are equipped with an intelligent control and regulation unit, such as a microcontroller, for example to control and regulate the operating mode of the high voltage component itself. Thus, such a microcontroller, which is already present in the high voltage component, can be used to generate a signal, such as a digital bit pattern, without incurring any additional circuitry-related costs.

[0033] In order to monitor the plug-in connector of the high-voltage component in the high-voltage circuit, it is envisaged to provide the signal generated by the device for generating a (digital) bit pattern directly at the second signal input of the evaluation unit. After transmitting this signal via a separate circuit, it is also envisaged to provide the signal generated by the device for generating a digital bit pattern at the first signal input of the evaluation unit.

[0034] The evaluation unit can then determine, by signal comparison of the signal at the first signal input and the signal at the second signal input, whether the connector of the high-voltage component has been correctly plugged in. If this is the case, as indicated by the two signals being identical, the evaluation unit will generate and issue a signal for enabling the high voltage for the high-voltage component, which is then applied.

[0035] It is also conceivable to provide the means for generating the digital bit pattern and the evaluation unit in a single unit as a signal generating and evaluating unit such as a microprocessor.

[0036] In order to match an on-board system that is already present in a vehicle, for example with an on-board voltage of 12 V, it is envisaged to carry out an adaptation of the signal level. This adaptation of the signal level is carried out between the expected signal level provided by the signal generation and evaluation unit and a higher signal level for transmission via a separate circuit and an interlocking bridge in the on-board voltage system of the vehicle.

[0037] Another advantage of performing such an adjustment of the signal level is the increase in the associated interference immunity. In addition, the associated costs for a 5V voltage generation unit, for example, which is used both for supplying the components for controlling the corresponding high-voltage components and for supplying the microprocessor as the signal generation and evaluation unit, are reduced.

[0038] Multiple level converters are used to adjust the signal level, such as adjusting the signal level from 5V to a 12V signal level, or adjusting the signal level from 12V to a 5V signal level.

[0039] Comparing the signal transmitted at the second signal input of the signal generation and evaluation unit with the signal received at the first signal input provides two benefits. First, it can be detected whether the connector of the high voltage component is correctly inserted. Secondly, it also enables the signal generation and evaluation unit to detect conditions such as short circuit to ground (GND) or short circuit to the operating voltage. The signal generation and evaluation unit then generates and outputs a corresponding signal based on the detected state.

[0040] These signals or states of the safety interlock device generated by the signal generating and evaluating unit are transmitted to a central control unit, for example, via a data bus present in the vehicle and are then processed accordingly in the control unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Further details, features and benefits of embodiments of the invention are derived from the following description of embodiments examples with reference to the accompanying drawings. These are shown below:

[0042] Figure 1: Prior art safety interlock.

[0043] Figure 2: Prior art safety interlock in the presence of multiple high voltage components.

[0044] Figure 3 : Safety interlock according to the present invention.

[0045] Figure 4 : Overview of the conditions that can be detected by the safety interlock according to the invention.

[0046] Figure 5 : An example of a circuit arrangement for a level converter for safety interlock according to the present invention.

[0047] Figure 6 : A flow chart depicting a method for monitoring electrical safety interlocks. DETAILED DESCRIPTION

[0048] Fig. 1 shows a device 1 for monitoring a prior art safety interlock. The high voltage component 2 from Fig. 1 to be supplied with a high voltage (greater than 60 VDC) is, for example, an inverter 2 of a refrigerant compressor, which is not shown in greater detail in Fig. 1 .

[0049] A high voltage electric wire 3 of a high voltage circuit is connected to the inverter 2 using a connector 4 to supply a high voltage.

[0050] The connector 4 is equipped with an interlocking bridge 5 known from the prior art, via which a safe connection of the connector 4 to a corresponding socket in the inverter 2 can be checked using a separate circuit 6, which is only hinted at in FIG. 1 .

[0051] For example, an evaluation unit 7 which is arranged in the inverter 2 and is only symbolically depicted in FIG. 1 is provided in order to carry out this check.

[0052] In order to check the safe connection of the high voltage electric line 3 on the inverter 2 using the connector 4 , it is envisaged to allow a current to flow through the interlocking bridge 5 , which current is then detected by an evaluation unit 7 arranged in the inverter 2 .

[0053] As already explained above, this solution is only partially safe and offers only limited robustness. Therefore, reliable monitoring of the electrical safety interlocks in the vehicle cannot be achieved.

[0054] FIG. 2 shows a device 1 for monitoring a safety interlock in the case of a plurality of high-voltage components 2 according to the prior art.

[0055] In order to check the safe connection of the high voltage wire 3 on the corresponding high voltage component 2 using the corresponding connector 4, it is envisaged to allow current to flow through the separate circuit 6 and the interlocking bridge 5. The safe attachment of the connector 4 is checked using an evaluation unit 7 which is also arranged in the separate circuit 6 and facilitates the current flow.

[0056] If the result of this detection is normal, a high voltage is applied to all high voltage components 2 via the high voltage wire 3. Therefore, this implementation helps to simultaneously monitor the safe connection of the connector 4 on multiple high voltage components 2. However, the disadvantages known from the prior art also apply to this implementation.

[0057] Figure 3 A device 8 for monitoring a safety interlock according to the invention is shown. In a high voltage component 2 such as an inverter 2, a signal generation and evaluation unit 9 is arranged, for example, to control the operation of the inverter 2. The signal generation and evaluation unit 9 - in this example intended as a microprocessor 9 - exhibits an output 10 for outputting a digital signal 11.

[0058] The signal 11 is a signal in which the signal level changes over time. For example, the bit pattern 11 can be generated by the signal generation and evaluation unit 9 as such a signal.

[0059] The signal 11 may be a binary signal presenting only two voltage levels. However, it is not envisaged to limit the signal 11 to only two voltage levels. Alternatively, the signal 11 may also be any other discrete and continuous signal.

[0060] The signal 11 , such as the bit pattern 11 , can be generated both according to the principle of random chance and based on a fixed rule. The bit pattern 11 with a sample sequence of zeros and ones is output via the output 10 .

[0061] This bit pattern 11 is transmitted via a first part 6a of the separate circuit to an interlocking bridge 5 in the connector 4. From the interlocking bridge 5 of the connector 4, the bit pattern 11 is routed back to the signal generating and evaluating unit 9 and the first signal input 12 via a second part 6b of the separate circuit.

[0062] It is envisaged to adjust the signal level of the signal 11 and thereby improve the interference immunity during the safe attachment of the detection connector 4 to the high-voltage electric line 3 on the high-voltage component 2. In order to perform such an adjustment of the signal level, a first level converter 13 is arranged directly at the output 10 of the signal generation and evaluation unit 9, which first level converter 13 increases the signal 11 exhibiting a 5V signal level to a 12V signal level at the output 10, for example, and then transmits the signal 11 exhibiting a 12V signal level via the parts 6a and 6b of the individual circuit 6 and the interlocking bridge 5. In this case, a second level converter 14 is arranged directly before the first signal input 12 and converts the signal 11 with a 12V level received from the second part 6b of the individual circuit into a signal 11 with a 5V level, which is then fed to the first signal input 12.

[0063] The signal 11 generated by the signal generating and evaluating unit 9 is also fed to a second signal input 15 of the signal generating and evaluating unit 9 .

[0064] In the case where the signal level has been raised to a 12V signal level by the first level converter 13, a third level converter 16 is arranged before the second signal input terminal 15, and the third level converter 16 adjusts the signal level of the signal 11 to the level of the second signal input terminal 15. In this example, the adjustment of the level from 12V to 5V is performed using the third level converter 16. In this example, a signal generation and evaluation unit 9 is used, which supplies a voltage of up to 5V at its output terminals, such as the output terminal 10, and can process signals with a voltage of up to 5V at its input terminals, such as the first signal input terminal 12 and the second signal input terminal 15. Of course, different voltages are possible when different signal generation and evaluation units 9 are used.

[0065] The signal generating and evaluating unit 9 which generates the signal 11 receives the generated signal 11 directly via the second signal input 15 in the form provided at the output 10 .

[0066] The signal generation and evaluation unit 9 also receives the signal 11 after it has been transmitted via the parts 6a and 6b of the individual circuit 6 and the interlocking bridge 5. In the case that the connector 4 has been correctly plugged in, the signal generation and evaluation unit 9 determines during a comparison of the signal at the first signal input 12 with the signal at the second signal input 15 that the two signals match at least in terms of their bit pattern. Differences in the amplitude or level of the signals are possible and do not affect the safety comparison.

[0067] When the signals match in this way, the connector 4 on the high voltage component 2 has been correctly plugged in and the signal generation and evaluation unit 9 can generate and output a signal for enabling the high voltage via the high voltage wire 3. This then activates the high voltage.

[0068] In the case where the connector 4 is not correctly inserted, which means that the separate circuit 6 cannot be connected to the parts 6a and 6b using the interlocking bridge 5, the signal generation and evaluation unit 9 determines that the two signals do not match when comparing the signal at the first signal input 12 with the signal at the second signal input 15. In this case, no signal for enabling the high voltage via the high-voltage line 3 is generated or output, which means that the high voltage will not be activated either. In this case, a corresponding fault signal can be generated and output by the signal generation and evaluation unit 9.

[0069] Figure 4 An overview of the conditions that can be detected by the safety interlock according to the invention is shown.

[0070] The first column shows that the signal 11 is continuously provided by the signal generation and evaluation unit 9 and that an evaluation, ie a comparison between the signal at the first signal input 12 and the signal at the second signal input 15 is performed.

[0071] In the second column the possible states of the individual circuit 6 with the parts 6a and 6b and the interlocking bridge 5 are shown. The third column lists the accompanying states of the second signal input 15 and the fourth column lists the accompanying states of the first signal input 12.

[0072] exist Figure 4 The first row of the table in FIG. 4 shows a correct connection of the connector 4 to the high-voltage component 2. Then, the signal 11 continuously supplied by the signal generation and evaluation unit 9 as a bit pattern is received via both the second signal input 15 and the first signal input 12. When the two signals match, a signal (not shown in the figure) for activating the high voltage via the high-voltage line 3 is generated and output by the signal generation and evaluation unit 9.

[0073] In the second row, the connector 4 is not correctly connected to the high voltage component 2. Therefore, the bit pattern 11 generated by the signal generation and evaluation unit 9 is received at the second signal input 15. The first signal input 12 is disconnected and does not receive the bit pattern 11. The disconnected first signal input 12 causes a high level to be detected. The fact that these signals do not match is detected by the signal generation and evaluation unit 9, and no signal for enabling the high voltage is issued. In this case, a fault signal indicating that the plug-in connection of the connector 4 is disconnected can be issued by the signal generation and evaluation unit 9.

[0074] The third row shows a fault state in which part 6a or 6b of the individual circuits or the interlocking bridge 5 presents a connection to ground potential. In this case, a low level is detected at both the second signal input 15 and the first signal input 12, and no signal for enabling a high voltage is provided. A fault signal indicating a short circuit to ground potential can be emitted by the signal generation and evaluation unit 9 here.

[0075] The fourth row shows a fault state in which part 6a or 6b of the individual circuits or the interlocking bridge 5 presents a connection to a voltage of, for example, 12 V, such as the operating voltage in a vehicle. In this case, a high level is detected at both the second signal input 15 and the first signal input 12, and no signal for enabling the high voltage is emitted. A fault signal indicating a short circuit to the 12 V operating voltage can be emitted here by the signal generation and evaluation unit 9.

[0076] The level converters 13 , 14 and 16 are designed with corresponding protection circuits so that they can continue to operate correctly in the case of a continuous input signal such as 0V or 12V.

[0077] Figure 5 The present invention is used for monitoring the Figure 3 The safety interlock device 8 of the embodiment shown (see Figure 3 ) is an example of a circuit arrangement of the level converters 13, 14 and 16 of FIG. This implementation of the first level converter 13, the second level converter 14 and the third level converter 16 is both illustrative and robust, but it does not limit the invention to only this version.

[0078] The signal 11 with a 5 V level generated by the signal generation and evaluation unit 9 and supplied via the output 10 is converted by a first level converter 13 comprising a transistor stage to a level of, for example, 12 V (for example) and then output via a first connection 17. The part 6 a of the individual circuit 6 is connected to this first connection 17, for example Figure 5 implied.

[0079] This level, which is present at the first connection 17 and measures, for example, 12 V, is fed directly to a third level converter 16 comprising two transistor stages. Level adjustment is again performed in this third level converter 16 in such a way that the signal 11 with a level of 5 V is supplied to the second signal input 15. The level of the signal 11 over time, for example the bit pattern, i.e. the sequence of zeros and ones, is not changed by any of the level converters 13, 14 or 16.

[0080] When the connector 4 has been correctly inserted, the signal 11 output at the first connection 17 is routed via the first part 6a of the separate circuit, via the interlocking bridge 5 of the connector 4 and via the second part 6b of the separate circuit to the second connection 18 and thus to the input of the second level converter 14. This second level converter 14, which comprises two transistor stages, performs level adjustment in such a way that the signal 11 at a 5V level is supplied to the first signal input 12.

[0081] The first connection 17 and the second connection 18 are each equipped with protection circuits 19. These protection circuits 19 implement overvoltage protection and thereby protect voltage-sensitive components of the level converters 13, 14 and 16 from damage caused by high voltage and high energy balancing processes at the connections 17, 18 and the individual circuits 6a, 6b.

[0082] The method according to the invention exhibits a high degree of interference immunity by using the signal 11 and facilitates safe detection of the correct insertion of the connector 4 into the corresponding socket of the high-voltage component 2 by performing a basic comparison of two signal patterns or bit patterns of the signal 11 .

[0083] Another advantage lies in the fact that energy savings can be achieved by using a corresponding design of the signal 11. A permanent current flow through the first part 6a and the second part 6b of the separate circuit is no longer necessary, and due to the reduction of the parts of the bit pattern 11 that are characterized by a high level of the signal 11, further energy savings can be achieved. For example, two pulses within a signal pattern that repeats itself in the signal 11 are sufficient for a safe detection of the condition of the connector 4. Such a bit pattern 11 also reduces thermal stresses in the accompanying electronics.

[0084] Since a short circuit to ground potential (GND) or the operating voltage results in a signal that differs from the bit pattern 11, this fault can also be detected using the invention.

[0085] As described in the example, detection of the correct insertion of the connector 4 into the corresponding socket of the high-voltage component 2 is achieved by the signal generating and evaluating unit 9 arranged directly in the high-voltage component 2. Monitoring by a separate control logic to be arranged in the vehicle can then be omitted.

[0086] It is also envisaged to transmit the states detected by the signal generation and evaluation unit 9 to the central control unit via a vehicle communication bus already present in the vehicle. Thus, the state of each high-voltage component 2 is reported to the central control unit. Standard systems such as a LIN bus (Local Interconnect Network) or a CAN bus (Controller Area Network) can be used as such a vehicle communication bus.

[0087] Figure 6 A flow chart describing a method for monitoring an electrical safety interlock is shown, wherein FIGS. 1 to 2 are described below. Figure 5 The reference numerals in the range 1 to 19 are not in Figure 6 The method starts in step 20 . In step 21 , the signal generation and evaluation unit 9 , which can be a microprocessor, is used to generate a time-varying signal, for example a bit pattern 11 , and outputs it via the output 10 .

[0088] After this, in step 22, a first check is performed to determine whether the bit pattern 11 is received by the first signal input 12 of the signal generating and evaluating unit 9. This check gives a positive result in the case where the bit pattern 11 is transmitted, for example, from the output 10 via the first part 6a of the individual circuit, the interlocking bridge 5 and the second part 6b of the individual circuit to the first signal input 12. Here, this transmission can also take place via the first level converter 13 and the third level converter 16 and / or a bit pattern 11 is received in which its signal level is inverted.

[0089] In the event of a positive result of this first check 22 , the method continues in step 23 by performing a second check on the bit pattern 11 received at the second signal input 15 and comparing the bit pattern 11 received at the input 12 with the bit pattern 11 received at the input 15 .

[0090] If the two bit patterns 11 match, it is detected that the connection of the connector 4 has been correctly established and a corresponding positive signal such as “plug-in connection established” is generated and output by the signal generation and evaluation unit 9 in step 24 . The method then ends with step 25 .

[0091] In the case where it is determined during the second check in step 23 that the bit pattern 11 does not match, it is detected that the connection of the connector 4 has not been correctly established, and a corresponding negative signal such as "plug-in connection disconnected" is generated and output by the signal generation and evaluation unit 9 in step 30. In this case, the method also ends with step 25.

[0092] In the event that it is determined during the first check in step 22 that the bit pattern 11 has not been received by the first signal input 12 of the signal generating and evaluating unit 9 , the method continues in step 26 in which the voltage level at the first signal input 12 is checked.

[0093] If during this check 26 it is determined that the high level of the signal is within the operating voltage range of 12 V, for example, a first state 27 is detected which indicates a short circuit to the operating voltage.

[0094] If during this check 26 it is determined that the low level of the signal is, for example, in the ground (GND) range, a state 27 is detected which indicates a short circuit to ground (GND).

[0095] In both cases, at least one fault signal is output in a subsequent step 29 before the method ends in step 25. Simultaneously with the output of the fault signal, the corresponding first state 27 or second state 28 can also be output in step 29.

[0096] Industrial Applicability

[0097] The invention relates to a device for monitoring electrical safety interlocks, the device comprising a connector with high voltage wires, wherein an interlock bridge is arranged in the connector and is connected to a first part of a separate circuit and a second part of the separate circuit when the connector is correctly connected to a high voltage component.

[0098] The invention also relates to a method for monitoring an electrical safety interlock, in which method a monitoring of a circuit of a safety interlock is performed, wherein the circuit is provided with a first part of a separate circuit and a second part of a separate circuit and an interlock bridge arranged in a connector.

[0099] In particular, the present invention relates to electrical safety interlocks used in vehicles that operate electrical components using a DC voltage of 60 V or higher. This is the case, for example, where an inverter is used in the vehicle, for example, which is required in order to convert the DC voltage into an AC voltage.

[0100] The invention also relates to a safety interlock for use in an electric vehicle or a vehicle with a so-called hybrid drive.

Claims

1. A device (8) for monitoring an electrical safety interlock, the device (8) comprising a connector (4) with a high voltage wire (3), wherein: The connector (4) accommodates a jumper (5) which is connected to a first part (6a) of the separate circuit and to a second part (6b) of the separate circuit when the connector (4) is correctly connected to the high-voltage component (2), characterized in that the separate circuits (6a, 6b) are connected to a signal generation and evaluation unit (9) which generates a continuous and discrete-valued signal (11), The signal generating and evaluating unit (9) exhibits an output (10) for outputting the signal (11), the output (10) being at least indirectly connected to the first part (6a) of the separate circuit, the second part (6b) of the separate circuit being at least indirectly connected to the first signal input (12), and the output (10) being at least indirectly connected to the second signal input (15), The signal (11) provided by the signal generating and evaluating unit (9) and output via the output terminal (10) is received by the signal generating and evaluating unit (9) via the second signal input terminal (15) in the first channel without passing through the jumper (5), the signal (11) is received by the signal generating and evaluating unit (9) via the first signal input terminal (12) in the second channel after being transmitted via the first part (6a) of the separate circuit, the jumper (5), and the second part (6b) of the separate circuit, and the signal generating and evaluating unit (9) performs monitoring of the electrical safety interlock by comparing the two received signals from both the first channel and the second channel.

2. The device (8) for monitoring electrical safety interlocking according to claim 1, characterized in that A first level converter (13) is arranged between the output terminal (10) and the first part (6a) of the individual circuit, a third level converter (16) is arranged between the second signal input terminal (15) and the first part (6a) of the individual circuit, and a second level converter (14) is arranged between the first signal input terminal (12) and the second part (6b) of the individual circuit.

3. The device (8) for monitoring electrical safety interlock according to claim 1, characterized in that The signal generating and evaluating unit (9) is a microprocessor.

4. A method for monitoring an electrical safety interlock, in which method monitoring of a circuit of a safety interlock is performed, wherein: The circuit is provided with a first part (6a) of a separate circuit and a second part (6b) of a separate circuit and a jumper (5) arranged in a connector (4), characterized in that monitoring of the circuit is performed using a continuous and discrete-valued signal (11), which is provided by a signal generation and evaluation unit (9) and which is evaluated by the signal generation and evaluation unit (9) via transmission of the circuit, The signal (11) provided by the signal generating and evaluating unit (9) and output via the output terminal (10) is received by the signal generating and evaluating unit (9) via the second signal input terminal (15) in the first channel without passing through the jumper (5), the signal (11) is received by the signal generating and evaluating unit (9) via the first signal input terminal (12) in the second channel after being transmitted via the first part (6a) of the separate circuit, the jumper (5), and the second part (6b) of the separate circuit, and the signal generating and evaluating unit (9) performs monitoring of the electrical safety interlock by comparing the two received signals from both the first channel and the second channel.

5. The method for monitoring electrical safety interlock according to claim 4, characterized in that: The signal (11) is transmitted on the second channel via the first part (6a) of the separate circuit, the jumper (5) and the second part (6b) of the separate circuit.

6. The method for monitoring electrical safety interlock according to claim 4, characterized in that: When the two received signals from the two channels are compared and it is found that the signals match each other, the signal generation and evaluation unit (9) outputs a signal indicating safe operation of the safety interlock, and when the two received signals from the two channels are compared and it is determined that there is no match or only a partial match, the signal generation and evaluation unit (9) outputs a signal indicating a safety interlock failure.

7. The method for monitoring electrical safety interlock according to claim 4, characterized in that: The signal (11) is a binary bit pattern.

8. The method for monitoring electrical safety interlock according to claim 4, characterized in that: The level of the signal (11) is changed before transmission via the individual circuit (6a, 6b) and after transmission via the individual circuit (6a, 6b).

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