DE102013209527A1 - Protection circuit for an actuator, actuator device and method for operating an electric actuator - Google Patents

Abstract

A protective circuit for an actuator for a vehicle has at least one switch (102) for interrupting and short-circuiting at least two electrical lines (111, 113) for connecting terminals (121, 123) of a power supply device to terminals (131, 133) of the electrical actuator on. The protective circuit also has a diagnostic device (104) for checking sections of the at least two electrical lines (111, 113) arranged between the connections (121, 123) of the energy supply device and the at least one switch (102).

Description

The present invention relates to a protection circuit for an actuator, to an actuator device and to a method for operating an electric actuator. In addition, the invention relates to an active chassis stabilizer and an active suspension control arm, each with such a protection circuit.

According to the prior art, methods for separating and / or short-circuiting the motor lines are already used in motor control applications. As protective elements usually mechanical switching elements such as contactors and / or relays and / or electronic switching elements, such as MOSFETs or IGBTs are used. In particular, the mechanical switching elements have the advantage that in the de-energized state of the coil circuit, the contacts open depending on the structure and technology and thus separate the load circuit (n.o.), or close (n.c.) to represent a short circuit. The mentioned technologies are also available in combination as so-called changeover contacts (n.o. & n.c).

The DE 102 57 211 A1 deals with a motor vehicle stabilizer. For the operation of an electric motor used as a generator, the motor phases of the electric motor can be short-circuited via a fixed or variable load resistor. When using a brushless DC motor whose short circuit is switched to operate as a generator via its output stage transistors.

Against this background, the present invention provides an improved protection circuit for an actuator, an improved actuator device, and an improved method of operating an electric actuator according to the main claims. Advantageous embodiments will become apparent from the dependent claims and the description below.

By such a protection circuit, an actuator can be decoupled from a power supply. Decoupling can be achieved by interrupting and additionally short-circuiting lines for connecting the actuator to the power supply. Advantageously, portions of the leads may be diagnosed while the actuator is decoupled from the power supply.

A protection circuit for an actuator for a vehicle is characterized in that the protection circuit comprises at least one switch for interrupting and shorting at least two electrical lines for connecting terminals of a power supply device to terminals of the electric actuator and a diagnostic device for checking between the terminals of the power supply device and the at least one switch arranged portions of the at least two electrical lines.

The actuator can be used, for example, in a vehicle for carrying passengers or transporting loads, for example in a motor vehicle. The electric actuator may constitute or include an electric motor. It can be an AC or DC operated actuator. The power supply device can be designed to provide required electrical energy to the terminals of the actuator via the terminals of the power supply and the electrical lines for operating the actuator. For example, two electrical lines or three electrical lines may be provided. Three electrical lines are suitable, for example, to operate the actuator with three-phase current. Each of the terminals of the power supply device can be supplied with electrical energy using power transistors of the power supply. A protection circuit can be understood to mean an electrical circuit which can be used to protect the actuator and additionally or alternatively the energy supply device or a control device coupled to the energy supply device from damage, for example due to voltage spikes. The at least one switch can be realized as a transistor, but advantageously as a mechanical switch, for example as a contactor or relay. By actuating the at least one switch, the lines can be interrupted and additionally short-circuited by the or a further actuation of the switch. For short circuiting, the cables can be connected directly or via a star point. The at least one switch may comprise a plurality of switching elements, or a plurality of switches may be provided, so that, for example, each of the lines may be assigned its own switch or its own switching element. According to one embodiment, the at least one switch can be designed to interrupt the lines and then short them. The switch can be designed as a changeover switch or changeover contact or a combination of individual nc and no switches. The diagnostic device can be designed as an electrical circuit. The diagnostic device may comprise discrete electrical components and additionally or alternatively a logic circuit. For example, the diagnostic device can be designed to provide a voltage measurement and additionally or for checking the sections of the lines alternatively carry out a current measurement. For this purpose, the diagnostic device can be designed to feed a diagnostic current or a diagnostic voltage into at least one of the lines. Depending on a result of such a measurement, the diagnostic device can diagnose, for example, a faultless or faulty state of the lines. A faulty state may be present, for example, when a short circuit or interruption is diagnosed on at least one of the lines that are not caused by the at least one switch.

The invention is preferably used in an active motor vehicle chassis. The invention can therefore relate to a suspension stabilizer of or for a motor vehicle (s), comprising an electric actuator and two stabilizer sections which can be rotated relative to one another by means of the actuator, and having the protection circuit for the actuator. Such a chassis stabilizer is also called roll stabilizer. Alternatively, the invention may relate to a suspension control arm of or for a motor vehicle (s), in particular a Hinterachsquerlenker, comprising an electric actuator and two by means of the actuator relative to each other displaceable wishbone sections, and having the protective circuit for the actuator.

According to one embodiment, the protection circuit may comprise a transfer device, which is designed to convert the actuator into a safe state. After successful transfer of the actuator to the safe state, the cables can be safely interrupted and short-circuited. As a result, a reliable switching of the at least one switch can be ensured.

The protection circuit may comprise a switching device. The switching device may be configured to provide a switching signal to the at least one switch in response to a transfer of the actuator to the safe state to interrupt and short the at least two electrical leads. The switching device may be configured to receive a transfer signal indicating that the actuator has entered the safe state. A safe state can be understood as a state in which the occurrence of voltage peaks during or after switching of the at least one switch can be avoided.

For example, the transfer device can be designed to connect the at least two electrical lines for transferring the actuator to the safe state with a reference voltage potential. The reference voltage potential can be provided for example by a ground connection. For example, corresponding power transistors in the power supply device can be suitably activated for this purpose. Thus, the electrical leads can be shorted to ground to achieve the safe condition of the actuator.

In this case, the transfer device can be designed to detect a current flow or a voltage drop between the at least two electrical lines and the reference voltage potential in order to detect the safe state. If no current flow or voltage drop is detected, it can be assumed that the actuator is in the safe state.

The diagnostic device can be designed to provide an enable signal to the switching device if the sections of the at least two electrical lines were diagnosed as being error-free when the sections were checked. Furthermore, the switching device can be designed to provide, in response to the enable signal, a further switching signal to the at least one switch in order to cancel the interruption and short-circuiting or only the interruption of the at least two electrical lines. When the diagnosis is made in a state in which the lines are broken and short-circuited, the at least one switch can be put into a state in which the lines are connected by the enable signal from a state in which the lines are disconnected and short-circuited are. When the diagnosis is made in a state where the lines are broken but not short-circuited by the at least one switch, the at least one switch can be put into a state by the enable signal from a state in which the lines are disconnected but not short-circuited be in which the lines are connected. In a switching state in which the lines are interrupted but not short-circuited, the at least one switch, for example, be offset before the actuator is put back into operation after a shutdown. By diagnosing the electrical lines, it can be ensured that a coupling between the power supply and the actuator is not restored until the sections are checked and considered faultless. A commissioning of the actuator with faulty connection cables can be avoided, however.

According to an embodiment, the switching device may be configured to receive an error signal and, in response to the error signal, to apply the switching signal to the at least one To provide a switch to interrupt and short the at least two electrical lines. For example, the error signal may indicate an error condition of a controller or a controller for controlling a function of the actuator. For example, the error signal may be provided by a monitoring device for monitoring the control device or the control device. In this way, a power supply of the actuator, in response to a detected or completed fault condition in the system, are automatically interrupted via the at least two electrical lines.

The protection circuit may include a housing having a first interface to the terminals of the power supply and a second external interface to the terminals of the actuator. The at least one switch, the diagnostic device and the at least one switch comprehensive areas of the lines can be arranged within the housing. The regions of the lines may run between the first and the second outer interface. Thus, the protection circuit may be arranged in a separate housing, which may be arranged separately from a housing of the actuator or a housing of the power supply. Such a protection circuit can be easily integrated into an existing system of power supply and actuator.

Alternatively, the protection circuit may be arranged in a housing of the actuator. As a result, the at least one switch of the protective device can be arranged very close to the actual contacts of the actuator, for example to contacts of windings of the actuator. In addition, actuator and protection circuit can be used as a compact unit.

For example, the diagnostic device may have at least one electrical resistance for connecting the sections of the at least two electrical lines. Furthermore, the diagnostic device can have a detection device. The detection device can be designed to detect a voltage drop and / or a current flow through the at least one electrical resistance for checking the sections. Resistance can be implemented easily and inexpensively. For example, the resistor may be connected between two of the electrical lines. Also, two resistors may be provided which connect a common star point in a star shape with two of the electrical lines. The at least one resistor may be disposed adjacent to or close to the at least one switch. The detection device may have a measuring device which is coupled to the at least two lines. The diagnostic device can be designed to decide, depending on a measurement result of the detection device, whether the at least two lines are faulty or error-free. According to one embodiment, the diagnostic device may be configured to perform the diagnosis when the at least one switch has shorted and interrupted the leads. According to a further embodiment, the diagnostic device may be designed to carry out the diagnosis if the at least one switch has interrupted the lines but has not short-circuited them. According to a further embodiment, the diagnostic device may be designed to carry out the diagnosis if the at least one switch has neither interrupted nor short-circuited the lines.

According to one embodiment, the at least one switch for interrupting and short-circuiting three electrical lines for connecting three terminals of the power supply device may be formed with three terminals of the electric actuator. The diagnostic device can be designed to check three three sections of the three lines arranged between the three terminals of the power supply device and the at least one switch. Thus, the protection circuit can be used in conjunction with a three-phase AC power supply and an actuator in the form of a three-phase machine. The three lines may be associated with the three phases of the three-phase alternating current.

Such a protection circuit can have three changeover switches or changeover contacts or, instead, a respective n.c. and n.o. switch for interrupting and short-circuiting the three electrical leads. The diagnostic device can have three electrical resistors for checking the three sections, which can connect the three sections with a common neutral point or the three sections with one another.

As mentioned above, said protective circuit can be used, for example, in connection with a chassis stabilizer of a vehicle.

An actuator device for a chassis stabilizer for a vehicle, wherein the actuator device comprises a power supply device and an actuator, wherein terminals of the power supply device are connected via at least two electrical lines to terminals of the electric actuator, is characterized in particular in that the actuator device, a said protection circuit for interrupting and Short-circuiting of at least two electrical lines. Thus, the said protective device can be used advantageously for operating an actuator. By way of example, the actuator device can be used in conjunction with a chassis stabilizer, by means of which a rolling movement of a vehicle can at least be reduced.

A method of operating an electric actuator for a vehicle is characterized in that, in a step of switching, at least two electrical leads for connecting terminals of a power supply to terminals of the electric actuator are interrupted and short-circuited using at least one switch and in a step of diagnosing between the terminals of the power supply device and the at least one switch arranged portions of the at least two electrical lines are checked.

In one embodiment, the method includes a step of transitioning the actuator to a safe state, wherein the step of switching is performed after the step of transferring.

Steps of such a process may be implemented by suitable means or carried out using suitable means. A device or device can be understood as an electrical device which processes electrical signals and can issue further signals as a function thereof. A device or device may have one or more suitable interfaces, which may be formed in hardware and / or software. For example, in a hardware configuration, the interfaces may be part of an integrated circuit in which functions of the device are implemented. The interfaces may also consist of their own integrated circuits and / or at least partially of discrete components. In a software training, the interfaces may be software modules that are present, for example, on a microcontroller in addition to other software modules.

A computer program product with program code which can be stored on a machine-readable carrier such as a semiconductor memory, a hard disk memory or an optical memory and is used to carry out said method when the program is executed on a computer or a device is also of advantage.

The invention will be described by way of example with reference to the accompanying drawings. Show it:

1 a schematic representation of a protection circuit for an actuator according to an embodiment of the present invention;

2 a schematic representation of an actuator device with a protection circuit according to an embodiment of the present invention;

3 a flow chart method for operating an electric actuator according to an embodiment of the present invention; and

4 a circuit diagram of an actuator device with a protection circuit according to an embodiment of the present invention.

In the following description of preferred embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and similarly acting, wherein a repeated description of these elements is omitted.

1 shows a schematic representation of a protection circuit for an actuator according to an embodiment of the present invention. The protection circuit has a switch device 102 and a diagnostic device 104 on. The switch device 102 and the diagnostic device 104 are with two wires 111 . 113 coupled to connect the actuator to a power supply.

The two lines 111 . 113 are between two first connections 121 . 123 and two second terminals 131 . 133 the protection circuit out.

The switching device 102 may include one or more switches. The switching device 102 is configured to in a first switching state, the lines 111 . 113 to keep in a continuously electrically conductive state and in a second switching state, the lines 111 . 113 to interrupt and additionally short-circuit. To short-circuit the two lines 111 . 113 For example, be electrically connected to each other directly or via a separately running connection line. According to one embodiment, the switching device 102 be trained to each of the lines 111 . 113 regardless of the other of the lines 111 . 113 to interrupt and, if necessary, short-circuit.

The diagnostic device 104 is formed to the sections of the lines 111 . 113 that between the first connections 121 . 123 and the switching device 102 are arranged to check. For example, the diagnostic device 104 be trained to put the sections on Short circuit, for example, to ground, or to monitor for an interruption. If the diagnostic device 104 diagnosed such error, the diagnostic device 104 for example, provide an error signal. For example, the switching device 102 be driven so that it only changes from the second switching state to the first switching state, and thus the connections 121 . 123 with the connections 131 . 133 connects when from the diagnostic device 104 no fault on the sections of the lines 111 . 113 is recognized.

According to one embodiment, the lines may 111 . 113 over the first connections 121 . 123 extend beyond, for example, to terminals of the power supply. For this purpose, more line parts to the first connections 121 . 123 be connected. As a result, by the diagnostic device 104 verifiable sections of the lines 111 . 113 for example, extend to internal or external terminals of the power supply device.

The protection circuit may include a housing and the first terminals 121 . 123 and additionally or alternatively, the second ports 131 . 133 can be arranged on housing walls of the housing and represent electrical interfaces of the protection circuit.

2 shows a schematic representation of an actuator device with a protection circuit according to an embodiment of the present invention. According to this embodiment, the actuator device becomes exemplary in a vehicle 200 used.

The actuator device has an actuator 202 , For example, an electric motor, and a power supply device 204 on. The power supply device 204 is designed to generate electrical energy for operating the actuator 202 provide. This is the power supply device 204 via lines 111 . 113 with the actuator 202 connected.

The protection circuit is designed to be the power supply device 204 from the actuator 202 to decouple. Furthermore, the protection circuit is formed around the lines 111 . 113 to check. For this purpose, the protection circuit, as shown by 1 described, a switching device 102 and a diagnostic device 104 on. Exemplary here are the first connections 121 . 123 the protection circuit equal to the terminals of the power supply device 204 and the second connections 131 . 133 the protection circuit equal to the terminals of the actuator 202 ,

According to this embodiment, the switching device 102 a first switch 241 and a second switch 243 on. The first switch 241 is in the first line 111 arranged and is formed to the first line 111 closed in the first switching state and to be kept interrupted in the second switching state. The second switch 243 is in the second line 113 arranged and is formed to the first line 113 closed in the first switching state and to be kept interrupted in the second switching state. In addition, the

switch 241 . 243 trained to be the first line 111 and the second line 113 short-circuit each other in the second switching state or in a third switching state, that is, an electrically conductive connection between the lines 111 . 113 manufacture. The conductive connection between the lines 111 . 113 can be done directly, for example, without additional connection to a reference voltage potential, such as ground.

The diagnostic device 104 For example, may have a resistance of the lines 111 . 113 electrically conductive interconnects. Furthermore, the diagnostic device 104 a measuring device or detection device 249 for measuring a voltage dropping across the resistor or a current flowing through the resistor, to a fault-free state or a faulty state of the lines 111 . 113 to be able to diagnose. In this case, the diagnostic device 104 depending on the embodiment be configured to perform the diagnosis while the switch 241 . 243 be in a switching state in which the lines 111 . 113 are not interrupted, in which the lines 111 . 113 interrupted but not short-circuited, or in which the wires 111 . 113 interrupted and shorted. Furthermore, the diagnostic device 104 be formed to a measuring current at a suitable location in the lines 111 . 113 feed or to the lines 111 . 113 to apply. For this purpose, the diagnostic device 104 also be designed to the power supply device 204 suitable to drive to the power supply device 204 to provide the measuring current or the measuring voltage.

According to one embodiment, the protection circuit has a switching device 250 on. The switching device 250 is formed, the switch device 102 head for. For this purpose, the switching device 250 be formed to a first switching signal for transferring the first switch 241 from the first switching state to the second switching state, or vice versa, to the first one switch 241 provide. Furthermore, the switching device 250 be formed to a second switching signal for transferring the second switch 243 from the first switching state to the second switching state, or vice versa, to the second switch 243 provide.

According to one embodiment, the diagnostic device 104 designed to be dependent on a result of a review of the lines 111 . 113 a diagnostic signal to the switching device 250 provide. The switching device 250 is formed according to this embodiment, the first and the second switching signal for transferring the switch 241 . 243 provide in the first switching state only if the diagnostic signal is a faultless state of the lines 111 . 113 displays. In the error-free state, the diagnostic signal may correspond, for example, to an enable signal.

According to one embodiment, the protection circuit comprises a transfer device 252 which is designed to be the actuator 202 into a safe state. For this purpose, the transfer device 252 be formed to the power supply device 204 suitable to drive to a transfer of the actuator 202 to bring about the safe state. For example, the power supply device 204 be controlled so that the lines 111 . 113 within the power supply device 204 be short-circuited via a reference voltage potential, such as ground. In response to a transfer of the actuator 202 in the safe state, the transfer device 252 be configured to send a signal to the switching device 250 provide that transferring the actuator 202 indicating in the safe state. The switching device 250 is formed according to this embodiment, the first and the second switching signal for transferring the switch 241 . 243 from the first to the second switching state only when the signal is the safe state of the actuator 202 displays.

According to one embodiment, parts of the protection circuit, for example, the switching device 250 , the transfer device 252 or parts of the diagnostic device 104 , or sections thereof may be arranged separately from the protection circuit or functionally associated with another component of the actuator device, for example a control device.

Preferably, the vehicle 200 a chassis and as part of the chassis on an active suspension stabilizer and / or a suspension control arm on. Such a chassis stabilizer is used in particular to roll movements of the vehicle 200 how they occur, for example, when cornering, to compensate or at least mitigate. The electric Akuator 202 is then in particular part of the suspension stabilizer and serves to rotate two stabilizer sections relative to each other, to specifically roll movements of the vehicle 200 counteract or initiate. Accordingly, the protection circuit may be part of an active vehicle stabilizer to bring it into a safe state. In contrast, the suspension control arm is used in particular to adjust or maintain a fall and / or a track of the chassis. The Akuator 202 is then in particular part of the vehicle stabilizer and serves to move two wishbone sections relative to each other to selectively change the lane and / or the fall of the chassis. In particular, when it comes to the suspension control arm is a Hinterachsquerlenker, thereby also a steering movement of the vehicle 200 be generated. Accordingly, the protection circuit may also be part of an active suspension control arm in order to convert it to a safe state.

3 FIG. 12 shows a flowchart of a method for operating an electric actuator according to an exemplary embodiment of the present invention. The method can be carried out in the context of a protection circuit, as determined by the 1 or 2 is described.

In one step 301 switching is interrupted electrical lines for connecting terminals of a power supply device to terminals of an electric actuator and additionally short-circuited. As a result, the actuator is decoupled from the power supply. In one step 303 of diagnosing the electric wires are checked. According to one embodiment, the step 303 of diagnosing after the step 301 of switching. The step 303 the diagnosing can be carried out once or several times.

For example, the step 301 be carried out when in an actuator comprehensive system, in particular in a control device for the actuator, an error has occurred. For this purpose, in a continuously repeated monitoring step, the system or parts of the system can be monitored for errors and the step 301 switching may be performed in response to an error detected in the monitoring step.

In an optional step 305 the lines can be closed again and the short circuit between the lines can be canceled again. The step 305 can, for example be executed when in step 303 of diagnostics no error was detected.

In an optional step 307 The actuator can be transferred to a safe state. The step 307 can before the step 301 the switching are performed so that the lines are interrupted only when the actuator is in the safe state.

4 shows a circuit diagram of an actuator device with a protection circuit 410 according to an embodiment of the present invention. The actuator device has a power supply device 204 and an electric actuator 202 on, over three electrical wires 111 . 113 . 413 connected to each other. A protection circuit 410 which is a switch device 102 and a diagnostic device 104 includes, is with the electrical wires 111 . 113 . 413 coupled. The electrical wires 111 . 113 . 413 are on the side of the actuator 202 over three connections 131 . 133 . 433 of the actuator 202 with the actuator 202 connected.

The switch device 102 has a first switch 241 , a second switch 243 and a third switch 445 on. The first switch 241 is in the first line 111 arranged and trained to the first line 111 to close in a first switching position and in an in 4 shown to interrupt second switching position and with a short-circuit network 460 connect to. The second switch 243 is in the second line 113 arranged and trained to the second line 113 to close in a first switching position and in an in 4 shown second switching position and with the short-circuit network 460 connect to. The third switch 445 is in the third line 413 arranged and trained to the third line 413 to close in a first switching position and in an in 4 shown second switching position and with the short-circuit network 460 connect to. In the in 4 shown second switching position of the switching device 102 are the electrical wires 111 . 113 . 413 interrupted and via the short-circuit network 460 shorted each other. The short circuit network 460 has a connection line and three contact sections connected to the connection line for the switches 241 . 243 . 445 on. When the switches 241 . 243 . 445 In the second switching position, the short-circuit network is electrically isolated, that is, with neither of the lines 111 . 113 . 413 still associated with an operating voltage potential, such as a ground potential. The switches 241 . 243 . 445 are designed as a changeover switch, each with a mechanically movable and electrically conductive switch section. Depending on the switching position connect the mechanically movable switch sections with the actuator 202 connected sections of the lines 111 . 113 . 413 with those with the power supply device 204 connected sections of the lines 111 . 113 . 413 or with the contact sections of the short-circuit network 460 ,

The diagnostic device 104 has a first resistance 462 on, the first lead 111 connects to a star point, a second resistance 464 on, the second line 113 connects to the star point and a third resistance 466 on, the third line 413 connects to the star point.

The protection circuit 410 and the actuator 202 can as a unit 470 be realized. For example, the protection circuit 410 and the actuator 202 be arranged in a common housing.

The power supply device 204 is part of a control device according to this embodiment 475 , in addition to the power supply device 204 a switching device 250 having. The control unit 475 may be implemented as a unit having a first port 480 and a second connection 482 having. About the first connection 480 is the switching device 250 of the control unit 475 with a line 478 connected. The switching device 250 is formed to the switch device 102 over the line 478 head for. About the second connection 482 is the energy supply 204 with the wires 111 . 113 . 413 connected. The control unit 475 may be spaced apart from the unit 470 from actuator 202 and protection circuit 410 be arranged. For example, a housing of the controller 475 spaced, without a contact point, to a housing of the unit 470 be arranged.

According to this embodiment, the power supply device 204 six transistor circuits 491 . 492 . 493 . 494 . 495 . 496 on. Each of the transistor circuits 491 . 492 . 493 . 494 . 495 . 496 has a transistor and a diode connected in parallel thereto. The first line 111 is via the first transistor circuit 491 with a voltage source 498 and via the second transistor circuit 492 connected to ground. The second line 113 is via the third transistor circuit 493 with the voltage source 498 and via the fourth transistor circuit 494 connected to ground. The third line 413 is via the fifth transistor circuit 495 with the voltage source 498 and via the sixth transistor circuit 496 connected to ground. By a suitable control of the transistor circuits 491 . 492 . 493 . 494 . 495 . 496 can the actuator 202 be supplied with a suitable operating voltage, for example a three-phase AC voltage.

According to one embodiment, the power supply device 204 designed as a power electronics or power amplifier, the switching device 250 is designed as a contactor and / or relay driver, also called a driver circuit, the first connection 480 is as a connector of the switching device 250 executed, the second port 482 is as a connector of the actuator 202 executed, the line 478 is as a connection line of the switching device 250 executed, the lines 111 . 113 . 413 are designed as actuator connecting lines, the resistors 462 . 464 . 466 are designed as diagnostic resistors and the switch device 102 is designed as a mechanical separator, for example as a contactor and / or relay.

Based on the preceding 1 to 4 are described in the following embodiments, which are based on mechanical protection elements 241 . 243 . 445 are based with changeover contacts and characterized in that by a diagnostic device 104 a diagnostic option of the electrical lines 111 . 113 . 413 in the form of motor connection lines or motor cables even after the separation or switching of the switch device 102 in the form of a contactor and / or relay is given.

In connection with the disconnection and short circuiting of the motor cables 111 . 113 . 413 arise three main tasks.

A first main task is to transfer 307 of the actuator 202 which can also be an engine, in a safe state, before switching 301 the or one of the protective elements 241 . 243 . 445 , This can be done by shorting the motor cables 111 . 113 . 413 via the final stage transistors 492 . 494 . 496 or be achieved by similar measures by which a braking torque is built up and against the mechanical excitation of the actuator 202 acts. This process can be performed by a transfer device 252 to be controlled. By a suitable measuring method, one for the switching of the switch device 102 Thus, for example, be determined for a contactor and / or relay switching appropriate time to avoid the emergence of voltage spikes.

In general, it is necessary that the actuator 202 , For example, a drive or motor, braked controlled in an error case. An unwanted acceleration of the actuator 202 should be avoided. According to one embodiment, the safe state of the actuator 202 hence the standstill of the actuator 202 ,

According to one embodiment, the actuator is 202 as explained above, part of an active electromechanical suspension stabilizer. Will the actuator 202 used for such an actuator for roll stabilization, so should the actuator 202 and thus also the vehicle body, after the adjusting process controlled to return to the zero position.

If a control unit that controls the actuator 202 used for roll stabilization, the clamped actuator 202 can not initiate a counter-moment by a field-oriented regulation, z. B. due to a failure of a microcontroller of the controller, so are the lines 111 . 113 . 413 of the actuator 202 , which are designed according to this embodiment as motor lines, shorted. This is due to the mechanical excitation of the actuator 202 induced voltage is short-circuited and by the short-circuit current, a counter-torque (braking torque) is initiated. This counter-torque prevents the sudden acceleration of the actuator 202 and also serves as surge protection.

Detecting the Safe State of the Actuator 202 can z. B. be realized by a current measurement. The relaxed actuator 202 can not induce voltage at standstill without mechanical excitation and the short circuit current goes back to zero. Due to the current measurement, the standstill of the actuator 202 be determined. If the separation is at a standstill, no high voltage spike is caused by the rapid current change (di / dt) in the motor winding of the actuator 202 induced.

A second main task concerns overvoltage protection. In case of failure, malfunction or shutdown of the control unit 475 it is necessary that the electronic components in the control unit (ECU) 475 and the power electronics of the power supply device 204 protected against overvoltage. This protective function is achieved by the switch device 102 , in the form of a mechanical protective element, the connecting line 111 . 113 . 413 between actuator 202 and control unit 475 disconnects (no contacts) and at the same time the motor windings of the actuator 202 Short circuits (NC contacts) to the regenerative effect of the actuator 202 to suppress.

For the overvoltage protection is thus an initiation of the short circuit after the separation process by the switch device 102 , In this case, a mechanical short circuit is automatically initiated after the separation process by the use of changeover contacts. The changeover contacts on the lines 111 . 113 . 413 as well as on the short circuit network 460 can through the as Changeover switch executed switch 241 . 243 . 445 be contacted.

According to one embodiment, a so-called fail-safe measure is designed so that after the transfer 307 of the actuator 202 in a safe operating condition the connection between actuator 202 and control unit 475 is interrupted. To the regenerative effect of the actuator 202 is suppressed by shorting the actuator lines performing lines 111 . 113 . 445 built up a counter-torque during mechanical excitations and thereby avoided overvoltage of the actuator circuit.

In case of failure, malfunction or shutdown of the control unit 475 become the actuator lines 111 . 113 . 445 automatically shorted and the connection between actuator 202 and control unit 475 separated.

A third main task concerns the diagnosis of motor cables 111 . 113 . 413 , Before the activation of the power amplifier 204 and the switch device 102 in the form of a separating element, the motor connection via the lines 111 . 113 . 413 checked for presence and short circuit. By disconnecting the motor connection (no contacts) there is no direct connection between the control unit 475 and the actuator 202 , The diagnostic device 104 in the form of an integrated detection circuit in the protection element 410 is provided to the motor connection lines 111 . 113 . 413 to be able to check in the separated state. As final elements can do this in the protective element 475 resistors 562 . 464 . 466 be used with star-shaped or alternatively as a triangular arrangement. Through the controlled closing of the connecting lines 111 . 113 . 413 the motor connection can be checked for errors before the power amplifier 204 and the separator 102 be unlocked.

Through the diagnostic resistors 462 . 464 . 466 can the connection lines 111 . 113 . 413 before the activation of the power amplifier 204 and the separating element 102 be checked for open circuit and short circuit by a suitable measuring method. Through this process, the actuator lines 111 . 113 . 413 even after the disconnection of the connection by the switch device 102 be checked and the reliability of the overall system can be increased.

According to one embodiment, the diagnostic resistors 462 . 464 . 466 be used for diagnosis when the lines 111 . 113 . 413 through the switch device 102 Although still interrupted, but are no longer shorted. For example, the switch device 102 be configured to perform the diagnosis of the lines 111 . 113 . 413 starting from a switching state by the lines 111 . 113 . 413 interrupted and shorted to change to a state in which the lines 111 . 113 . 413 interrupted, but not on the switch device 102 are shorted. If no error is diagnosed during diagnosis, the switch device may 102 change to a state in which the lines 111 . 113 . 413 are connected again.

The protection circuit 410 Can be both external, and actuator 202 internal unit to be executed.

The described technical solution can be supplemented by two additional switching contacts in the short circuit. This will short-circuit the actuator lines 111 . 113 . 413 individual design depending on the application. Furthermore, the changeover contacts can be replaced by no and nc contacts.

The embodiments described and shown in the figures are chosen only by way of example. Different embodiments may be combined together or in relation to individual features. Also, an embodiment can be supplemented by features of another embodiment. Furthermore, method steps according to the invention can be repeated as well as carried out in a sequence other than that described. If an exemplary embodiment comprises a "and / or" link between a first feature and a second feature, this can be read so that the embodiment according to one embodiment, both the first feature and the second feature and according to another embodiment, either only the first Feature or only the second feature.

LIST OF REFERENCE NUMBERS

102

switch device

104

diagnostic device

111

first line

113

second line

121

first connection

123

another first connection

131

second connection

133

another second connection

200

vehicle

202

actuator

204

Power supply means

241

first switch

243

second switch

249

detector

250

switching device

252

Transfer device

301

Step of switching

303

Step of diagnosing

305

Step of closing

307

Step of convicting

410

protection circuit

413

third line

433

another second connection

445

third switch

460

Short circuit network

462

first resistance

464

second resistance

466

third resistance

470

Unit of protection circuit and actuator

475

control unit

478

management

480

first connection

482

second connection

491

first transistor circuit

492

second transistor circuit

493

third transistor circuit

494

fourth transistor circuit

495

fifth transistor circuit

496

sixth transistor circuit

498

voltage source

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10257211 A1 [0003]

Claims (12)

Protection circuit ( 410 ) for an actuator for a vehicle ( 200 ), characterized in that the protection circuit ( 410 ) at least one switch ( 102 ; 241 . 243 ; 445 ) for interrupting and short-circuiting at least two electrical lines ( 111 . 113 ; 413 ) for connecting terminals ( 121 . 123 ; 482 ) a power supply device ( 204 ) with connections ( 131 . 133 ) of the electric actuator ( 202 ) and a diagnostic device ( 104 ) for checking between the terminals ( 121 . 123 ; 482 ) of the power supply device ( 204 ) and the at least one switch ( 102 ; 241 . 243 ; 445 ) arranged portions of the at least two electrical lines ( 111 . 113 ; 413 ) having. Protection circuit ( 410 ) according to claim 1, characterized in that the protection circuit ( 410 ) a transfer device ( 252 ), which is designed to hold the actuator ( 202 ) to a safe state, and a switching device ( 250 ) which is adapted to be in response to a transfer of the actuator ( 202 ) in a safe state, a switching signal to the at least one switch ( 102 ; 241 . 243 ; 445 ) to provide the at least two electrical leads ( 111 . 113 ; 413 ) and short circuit. Protection circuit ( 410 ) according to claim 2, characterized in that the transfer device ( 252 ) is formed around the at least two electrical lines ( 111 . 113 ; 413 ) for transferring the actuator ( 202 ) to connect to the safe state with a reference voltage potential. Protection circuit ( 410 ) according to claim 2 or 3, characterized in that the transfer device ( 252 ) is adapted to a current flow or a voltage drop between the at least two electrical lines ( 111 . 113 ; 413 ) and the reference voltage potential to detect the safe state. Protection circuit ( 410 ) according to claims 2 to 4, characterized in that the diagnostic device ( 104 ) is adapted to send a release signal to the switching device ( 250 ) when the sections of the at least two electrical lines ( 111 . 113 ; 413 ) were diagnosed as faultless when checking the sections, and the switching device ( 250 ) is formed in response to the enable signal, a further switching signal to the at least one switch ( 102 ; 241 . 243 ; 445 ) to interrupt and short-circuit the at least two electrical leads ( 111 . 113 ; 413 ). Protection circuit ( 410 ) according to one of the preceding claims, characterized in that the diagnostic device ( 104 ) at least one electrical resistance ( 462 . 464 . 466 ) for connecting the sections of the at least two electrical lines ( 111 . 113 ; 413 ) and a detection device ( 249 ), which is designed to detect a voltage drop and / or a current flow through the at least one electrical resistance (FIG. 462 . 464 . 466 ) capture. Protection circuit ( 410 ) according to one of the preceding claims, characterized in that the at least one switch ( 102 ; 241 . 243 ; 445 ) for interrupting and short-circuiting three electrical lines ( 111 . 113 ; 413 ) for connecting three connections ( 121 . 123 ; 482 ) of the power supply device ( 204 ) with three connections ( 131 . 133 ; 433 ) of the electric actuator ( 202 ) and the diagnostic device ( 104 ) to check three between the three ports ( 121 . 123 ; 482 ) of the power supply device ( 204 ) and the at least one switch ( 102 ; 241 . 243 ; 445 ) arranged three sections of the three lines ( 111 . 113 ; 413 ) is trained. Protection circuit ( 410 ) according to claim 7, characterized in that the protection circuit ( 410 ) three changeover switches ( 102 ; 241 . 243 ; 445 ) for interrupting and short-circuiting the three electrical lines ( 111 . 113 ; 413 ) and the diagnostic device ( 104 ) for checking the three sections three electrical resistances ( 462 . 464 . 466 ), which connect the three sections with a common star point or the three sections with each other. Actuator device for a chassis stabilizer for a vehicle ( 200 ), wherein the actuator device comprises a power supply device ( 204 ) and an actuator ( 202 ), where connections ( 121 . 123 ; 482 ) of the power supply device ( 204 ) via at least two electrical lines ( 111 . 113 ; 413 ) with connections ( 131 . 133 ; 433 ) of the electric actuator ( 202 ), characterized in that the actuator device comprises a protection circuit ( 410 ) according to one of the preceding claims for interrupting and short-circuiting the at least two electrical lines ( 111 . 113 ; 413 ) having. Method for operating an electric actuator ( 202 ) for a vehicle ( 200 ), characterized in that in one step ( 301 ) of switching at least two electrical lines ( 111 . 113 ; 413 ) for connecting terminals ( 121 . 123 ; 482 ) a power supply device ( 204 ) with connections ( 131 . 133 ; 433 ) of the electric actuator ( 202 ) using at least one Switch ( 102 ; 241 . 243 ; 445 ) are interrupted and short-circuited and in one step ( 303 ) of diagnosing between the terminals ( 121 . 123 ; 482 ) of the power supply device ( 204 ) and the at least one switch ( 102 ; 241 . 243 ; 445 ) arranged portions of the at least two electrical lines ( 111 . 113 ; 413 ). Chassis stabilizer for a motor vehicle ( 200 ), comprising an electric actuator ( 202 ) and two by means of the actuator ( 202 ) rotatable relative to each other stabilizer sections, and having a protective circuit according to one of claims 1 to 8 for the actuator ( 202 ). Suspension control arm, in particular rear axle wishbone, for a motor vehicle ( 200 ), comprising an electric actuator ( 202 ) and two by means of the actuator ( 202 ) relatively displaceable wishbone sections, and having a protective circuit according to one of claims 1 to 8 for the actuator ( 202 ).

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