Roll stabilizer for a vehicle and method for operating an actuator device of a roll stabilizer

Abstract

Roll stabilizer for a vehicle (100) comprising an actuator device (101) and two stabilizer elements (102, 104) coupled to each other via an actuator (106) of the actuator device (101) to effect a relative movement between the stabilizer elements (102, 104), wherein the actuator device (101) has a supply line connection (116) for providing a supply voltage to a supply connection (114) of a converter (108), the converter (108) for providing an alternating voltage using the supply voltage, an actuator (106) operable by the alternating voltage, and an eddy current brake (110) having an eddy current brake connection (234) coupled to a shaft (120) of the actuator (106), wherein the actuator device (101) has a control device (112) configured to To activate the eddy current brake (110) in response to generator operation of the actuator (106).

Description

[0001] The present invention relates to a roll stabilizer for a vehicle and a method for operating an actuator device of a roll stabilizer.

[0002] EP 1 894 755 B1 discloses a chassis arrangement with a stabilizer, in which each stabilizer section is assigned a braking device by which the torsional rigidity of the respective stabilizer section can be influenced. The braking device can be designed as an eddy current brake.

[0003] Against this background, the present invention provides a roll stabilizer for a vehicle with an improved actuator device and an improved method for operating an actuator device of a roll stabilizer according to main claims 1 and 9. Advantageous embodiments are set forth in the dependent claims and the following description.

[0004] An actuator operating as a generator can be reliably braked using an eddy current brake.

[0005] An actuator device for a vehicle roll stabilizer comprises a supply line connection for providing a supply voltage to a supply terminal of a converter, the converter for providing an alternating voltage using the supply voltage, an actuator operable by the alternating voltage, and an eddy current brake having an eddy current brake connection, which is coupled to a shaft of the actuator. Furthermore, the actuator device comprises a control unit configured to activate the eddy current brake in response to generator operation of the actuator.

[0006] The actuator can be a motor, particularly an electric motor. For example, the actuator can be an AC motor, especially a brushless one, or a three-phase motor. The converter can be designed to convert a DC voltage into an AC voltage required to operate the actuator. The actuator's power output can be controlled via a characteristic of the AC voltage. Thus, the converter can be considered a control unit for controlling the actuator or be part of such a control unit. For example, the converter can be designed as an inverter. The converter can include a bridge circuit for converting the supply voltage into the AC voltage. The supply voltage can be a DC voltage provided by an electrical system, for example, a 48V or 12V electrical system.Depending on the specific embodiment, two, three, or more phase lines can be provided to operate the actuator. In generator mode, the actuator can generate a generator voltage and feed it into the converter. Generator mode can occur, for example, when the converter is no longer supplied with the supply voltage and thus no voltage, particularly AC voltage, is provided by the converter to operate the actuator. By activating the eddy current brake, the actuator can be decelerated, thereby reducing the generated generator voltage. When the eddy current brake is activated, an electromagnet of the eddy current brake can be energized to generate a magnetic field that produces a braking effect to decelerate the actuator.According to different embodiments, the eddy current brake can always be activated as soon as the generator operation begins, or, for example, can be activated when the generator operation is in progress and the generated generator voltage cannot be used for other purposes, such as charging a battery.

[0007] The control unit can include a circuit configured to connect the converter's supply terminal to the actuator's supply line terminal during actuator operation and to the eddy current brake terminal during generator operation. In this way, the actuator can be supplied with the operating voltage required for its operation during actuator operation and braked via the eddy current brake during generator operation.

[0008] For example, such a circuit can be implemented as an XOR circuit. This ensures that the converter's supply terminal is not connected simultaneously with the power supply terminal and the eddy current brake terminal, which would prevent the actuator from being driven and braked at the same time.

[0009] The control unit can be configured to activate the eddy current brake using a generator voltage generated by the actuator during its generator operation. In this way, the generator voltage can be used effectively while simultaneously keeping it away from components sensitive to the generator voltage.

[0010] The control unit can be configured to supply a generator voltage, generated by the actuator during generator operation, to the eddy current brake terminal of the eddy current brake. For example, the voltage supplied to the eddy current brake terminal can be used to generate a magnetic field by an electromagnet of the eddy current brake.

[0011] The control unit can be configured to activate the eddy current brake in response to an interruption of the supply voltage at the supply line connection. An interruption of the supply voltage can be understood as a situation where no or a significantly reduced supply voltage is provided at the supply line connection. This can occur, for example, if a supply line connected to the supply line connection is interrupted. Such an interruption typically results in generator operation. By activating the eddy current brake, braking of the actuator can begin early to minimize undesirable effects of generator operation.

[0012] The control unit can be configured to activate the eddy current brake using a DC link voltage applied to an intermediate circuit of the actuator device. For example, the DC link voltage can be used to detect whether the generator voltage generated during generator operation can no longer be used for energy recuperation, and therefore generator operation should be discontinued.

[0013] The eddy current brake can consist of an electrically conductive, non-magnetic disc and at least one electromagnet arranged adjacent to the disc. Such a brake is simple and inexpensive to implement.

[0014] In a vehicle equipped with a roll stabilizer, the roll stabilizer can include a corresponding actuator device. The roll stabilizer can have two stabilizer elements, with the actuator of the actuator device being coupled to the stabilizer elements to effect a relative movement that influences the vehicle's roll. Thus, the described approach can be advantageously applied to a vehicle.

[0015] Method for operating an actuator device for a roll stabilizer for a vehicle, wherein the actuator device has a supply line connection for providing a supply voltage to a supply connection of a converter, the converter for providing an alternating voltage using the supply voltage, an actuator operable by the alternating voltage and an eddy current brake having an eddy current brake connection coupled to a shaft of the actuator, characterized in that the method comprises a step of activating the eddy current brake in response to generator operation of the actuator.

[0016] The control unit can be an electrical device that processes electrical signals, such as sensor signals, and outputs control signals accordingly. The control unit can have one or more suitable interfaces, which can be implemented in hardware and / or software. In the case of a hardware implementation, the interfaces can, for example, be part of an integrated circuit in which the functions of the control unit are implemented. The interfaces can also be separate integrated circuits or consist at least partially of discrete components. In the case of a software implementation, the interfaces can be software modules that are present, for example, on a microcontroller alongside other software modules. Fig. 1 a schematic representation of a vehicle with an actuator device according to an embodiment of the present invention; Fig. 2 a schematic representation of an actuator device according to an embodiment of the present invention; Fig. 3 a schematic representation of an eddy current brake according to an embodiment of the present invention; Fig. 4 a schematic representation of an actuator device according to an embodiment of the present invention; and Fig. 5 a flowchart of a method for operating an actuator device for a roll stabilizer for a vehicle according to an embodiment of the present invention.

[0017] 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 having a similar effect, without repeating these elements.

[0018] Fig. Figure 1 shows a schematic representation of a vehicle 100 with a roll stabilizer comprising an actuator device 101 according to an embodiment of the present invention. In addition to the actuator device 101, the roll stabilizer comprises two stabilizer elements 102, 104, which are coupled to each other via an actuator 106 of the actuator device 101. A roll movement of the vehicle 100, which is detected, for example, by suitable sensors, can be reduced or prevented by a relative movement of the stabilizer elements 102, 104 relative to each other caused by the actuator 106. The actuator 106 can be rotationally fixed to a first stabilizer element 102, while the other stabilizer element 104 can be rotated relative to the first stabilizer element by the actuator, preferably via a transmission, in particular a gear transmission.Accordingly, the actuator 106 can cause or reduce a relative movement between the stabilizer elements 102, 104, which causes a desired or unintended roll movement of the vehicle 100, for example a roll movement or reduction requested by a driver assistance device.

[0019] The actuator device 101 comprises, in addition to the actuator 106, which is also referred to as a motor, a converter 108, an eddy current brake 110, and a control unit 112. The converter 108 is configured to supply the actuator 106 with an alternating voltage required for its operation. For this purpose, the converter 108 is connected to the actuator 106 via phase lines, typically three phase lines. The converter 108 is configured to provide the alternating voltage using a supply voltage supplied at a supply terminal 114 of the converter 108. According to this embodiment, the supply terminal 114 is connected via a line to a supply line terminal 116 of a power supply device 118, for example, a battery of the vehicle 100. The power supply device 118 is configured to provide the supply voltage.

[0020] The actuator 106 and the eddy current brake 110 are mechanically coupled to each other via a shaft 120. In this way, the rotary motion of the actuator 106 can be braked using the eddy current brake 110. When the actuator 106 is operating as a generator, the eddy current brake 110 is not active, so the actuator 106 is not braked by the eddy current brake 110. In one embodiment, the actuator 106 is braked using the eddy current brake 110. For this purpose, the eddy current brake 110 is activated. According to one embodiment, the activation of the eddy current brake 110 is controlled by the control unit 112.

[0021] The generator operation of actuator 106 can, for example, respond to an interruption in the line connecting the supply terminal 114 to the supply line terminal 116. If the supply voltage is interrupted during the operation of actuator 106, the actuator 106 acts as a generator and feeds a generator voltage into the converter 108. If the generator voltage is not used, for example, for recharging the power supply unit 118, the generator voltage can cause damage. To prevent or at least reduce such undesired generator operation of actuator 106, the movement of actuator 106 that causes the generator voltage can be slowed by activating the eddy current brake 110.

[0022] Fig. Figure 2 shows a schematic representation of an actuator device 101 according to an embodiment of the present invention. This can be an actuator device 101 which, as shown by Fig. As described in Figure 1, the actuator device 101 can be used for a roll stabilizer or for other applications. The actuator device 101 comprises the actuator 106, the eddy current brake 110, and the control unit 112. According to this embodiment, the eddy current brake 110 has an electrically conductive disc 230 and an electromagnet 232. In one embodiment, the disc 230 is rigidly connected to the shaft 120. In this embodiment, the disc 230 of the eddy current brake 110 is conductive but not magnetic. The two poles of the electromagnet 232 are arranged on opposite sides of the disc 230.

[0023] According to this embodiment, the actuator 106 is designed as a motor.

[0024] According to one embodiment, the control unit 112 is designed as a "safety circuit". If a fault occurs, the electromagnet 232 or the electromagnets of the eddy current brake 110 are energized. During actuator operation of the actuator 106, also referred to as normal operation, the electromagnet 232 is not energized. To energize the electromagnet 232, the control unit 112 is connected via a line to an eddy current brake terminal 234 of the eddy current brake 110.

[0025] According to one embodiment, a generator current of the actuator 106, also referred to as regenerative current, is used to power the electromagnet(s) 232.

[0026] The described approach has several advantages. For example, the actuator 106 can be braked more effectively the faster the actuator 106, and thus the disc 230 of the eddy current brake 110, rotates. This closely resembles the behavior of conventional stabilizers: the greater the torsion or rotational speed of the actuator, the greater the counter-torque required to brake it. This counter-torque, also called support torque, increases with the degree of rotation (angle of rotation). The described approach can also be used in the event of a sudden fault, such as a disconnected connector, when the actuator 106 is supplying power to the magnets 232 in generator mode. Advantageously, no losses or power consumption occur during normal operation. Power consumption and the associated losses only occur in the event of a fault or when the system is switched off.Advantageously, component protection can be achieved in this way, since the regenerative current can be used for the brake 110 or the magnet 232 of the brake 110.

[0027] According to this embodiment, the control unit 112 is connected to the actuator 106 via lines. This enables the control unit 112 to activate and / or operate the eddy current brake 110 using the generator voltage generated during the generator operation of the actuator 106. To operate the eddy current brake 110 using the generator voltage, the control unit 110 is configured, according to one embodiment, to supply the generator voltage generated by the actuator 106 to the eddy current brake terminal 234 of the eddy current brake 110.

[0028] According to one embodiment, the eddy current brake 110 is used as passive damping in electromechanical roll stabilizers. The passive damping based on the eddy current brake 110 can be used in addition to or as an alternative to braking devices based on other operating principles. For example, the eddy current brake 110 can be used in addition to or as an alternative to a braking device based on a phase short circuit at the actuator 106, which results in a strong braking effect in an electric motor, to a braking device based on a magnetorheological principle, or to a braking device as a friction-fit connection. The eddy current brake 110 enables a passive stabilizer function and residual damping in the event of a system failure, for example, caused by a cable break, short circuit, or overvoltage. This allows for the implementation of a failsafe device.

[0029] The described approach is based on the use of the eddy current principle. The rotation of the stabilizer halves by external torques causes the actuator 106, designed as a motor, to operate as a generator. According to one embodiment, the energy generated is used to power the eddy current brake 110. This protects the other components of the system from overvoltage and dampens or brakes the rotation of the two stabilizer halves.

[0030] The disc 230 and the magnet 232 of the eddy current brake 110 can be integrated as additional components in an electronic unit encompassing the actuator.

[0031] Fig. Figure 3 shows a schematic representation of an eddy current brake 110 according to an embodiment of the present invention. This can be an embodiment of the invention based on Fig. The eddy current brake 110 shown in Figure 2 comprises a disk 230 and an electromagnet 232. Fig. 3 is a distance r between an axis of rotation of the disk 230 and a center point of the electromagnet 232, designated by reference numeral 340. A braking force F GK is indicated by reference numeral 342. A rotational speed of the disc 230 is indicated by reference numeral 344. A braking torque M GK can be determined according to the formula M GK = F GK * determine r.

[0032] Fig. Figure 4 shows a schematic representation of an actuator device 101 according to an embodiment of the present invention. This can be an embodiment of the actuator device described with reference to the preceding figures. The actuator device comprises an actuator 106, a converter 108, an eddy current brake 110, and a control unit 112. According to this embodiment, the converter 106 is implemented as a bridge circuit that provides a three-phase alternating voltage to the actuator 106, which, according to this embodiment, is designed as a three-phase motor and is also referred to as the actuator.

[0033] According to this embodiment, the control unit 112 comprises a circuit 412 configured to connect the supply terminal 114 of the converter 108 to the supply line terminal 116 during actuator operation of the actuator 106, and to the eddy current brake terminal 234 of the eddy current brake 110 during generator operation of the actuator 106. For this purpose, the circuit 412, according to one embodiment, includes a logic XOR gate. Such a circuit 412 serves as a safeguard to prevent simultaneous braking and driving. According to this embodiment, the circuit 412, also referred to as a disconnect device, is controlled by a device 450 for controlling the circuit 412. The device 450 is controlled by a device 452 for targeted software control and / or by a higher-level control unit 454 and / or by a device 456 for detecting a threshold exceedance.The arrows between the devices 112, 450, 452, 454, 456 indicate a direction of action. According to one embodiment, the devices 450, 452, 454, 456 are part of the control device 112. Alternatively, they are separate devices 450, 452, 454, 456.

[0034] Device 452 enables targeted software control and can be used, for example, in conjunction with a safety function in an electrically driven and electronically controlled roll stabilization system. Device 454 enables higher-level control, which can originate, for example, from the vehicle. Device 456 can be used, for example, to activate the eddy current brake 110 when a DC link voltage in a DC link 460 exceeds a threshold value. This might occur, for example, when energy recuperation is not possible.

[0035] The intermediate circle 460, which is in Fig. 4, represented by a capacitor, together with the converter 108 forms a motor control unit 462.

[0036] Fig. Figure 5 shows a flowchart of a method for operating an actuator device for a roll stabilizer for a vehicle according to an embodiment of the present invention. This actuator device can be such as that described with reference to the preceding figures.

[0037] The procedure includes a step 530 in which generator operation of the actuator is detected. Such detection can be achieved, for example, using the criteria based on… Fig.The procedures described in section 4 are carried out. In step 532, the eddy current brake is activated when the actuator is in generator mode. Activation can occur immediately after generator operation is detected or with a delay, for example, when the DC link voltage exceeds the specified threshold.

[0038] If an embodiment includes an “and / or” connection between a first feature and a second feature, this can be interpreted as meaning that the embodiment according to one embodiment has both the first feature and the second feature, and according to another embodiment either only the first feature or only the second feature. Reference sign 100 vehicles 101 Actuator device 102 Stabilizer element 104 Stabilizer element 106 Actuator 108 converters 110 Eddy current brake 112 Control unit 114 Supply connection 116 Supply line connection 118 Energy supply facility 120 wave 230 disc 232 Electromagnet 234 Eddy current brake connection 340 distance 342 force 344 rotational speed 412 Circuit 450 Device for controlling the control device 452 Device for targeted software control 454 Regulation 456 Device for detecting a threshold exceedance 460 Intermediate circle 462 Motor control unit 530 Step of Recognition Step 532 of activation

Claims

[1] Roll stabilizer for a vehicle (100) comprising an actuator device (101) and two stabilizer elements (102, 104) coupled to each other via an actuator (106) of the actuator device (101) to effect a relative movement between the stabilizer elements (102, 104), wherein the actuator device (101) has a supply line connection (116) for providing a supply voltage to a supply connection (114) of a converter (108), the converter (108) for providing an alternating voltage using the supply voltage, an actuator (106) operable by the alternating voltage, and an eddy current brake (110) having an eddy current brake connection (234) coupled to a shaft (120) of the actuator (106), wherein the actuator device (101) has a control device (112) configured to to activate the eddy current brake (110) in response to generator operation of the actuator (106). [2] Roll stabilizer according to claim 1, characterized by , that the control device (112) has a circuit (412) configured to connect the supply terminal (114) of the converter (108) to the supply line terminal (116) during actuator operation of the actuator (106) and to the eddy current brake terminal (234) of the eddy current brake (110) during generator operation. [3] Roll stabilizer according to claim 2, characterized by , that the circuit (412) is implemented as an XOR circuit. [4] Roll stabilizer according to any of the preceding claims, characterized by , that the control device (112) is designed to activate the eddy current brake (110) using a generator voltage generated by the actuator (106) in the generator operation of the actuator (106). [5] Roll stabilizer according to any of the preceding claims, characterized by, that the control device (112) is designed to provide a generator voltage generated by the actuator (106) in the generator operation of the actuator (106) to the eddy current brake terminal (234) of the eddy current brake (110). [6] Roll stabilizer according to any of the preceding claims, characterized by , that the control device (112) is designed to activate the eddy current brake (110) in response to an interruption of the supply voltage at the supply line connection (116). [7] Roll stabilizer according to any of the preceding claims, characterized by , that the control device (112) is designed to activate the eddy current brake (110) using an intermediate circuit voltage applied to an intermediate circuit (460) of the actuator device (101). [8] Roll stabilizer according to any of the preceding claims, characterized by, that the eddy current brake (110) has an electrically conductive, non-magnetic disk (230) and at least one electromagnet (232) arranged adjacent to the disk (230). [9] Method for operating an actuator device (101) of a roll stabilizer according to any one of claims 1 to 8, characterized by , that the procedure includes a step (532) of activating the eddy current brake (110) responding to a generator operation of the actuator (106).

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