Redundant power supply architecture for two independent boardnets with cross connection to support supply from only one power input for electronic brake systems

Abstract

The invention relates to a braking system for a motor vehicle. In detail, the invention relates to a redundant power supply architecture for two independent boardnets to support energy supply from only one power input. The braking system may comprise an electrohydraulic and / or an electronic brake system.

Description

[0001] REDUNDANT POWER SUPPLY ARCHITECTURE FOR TWO INDEPENDENT BOARDNETS WITH CROSS CONNECTION TO SUPPORT SUPPLY FROM ONLY ONE POWER INPUT FOR ELECTRONIC BRAKE SYSTEMS

[0002] The invention relates to an electronic braking system for a motor vehicle. In detail, the invention relates to a redundant power supply architecture for two independent boardnets to support energy supply from only one power input. The braking system may comprise an electrohydraulic or an electro-mechanical braking system.

[0003] Electronic brake systems in motor vehicles may include hydraulic brake circuits to control braking at each of the wheels. Some of these systems are by-wire brake systems with redundant hydraulic controls. Recently some systems have included hydraulic brake circuits for the front axle and electro-mechanical braking at the rear axle. For pressure generation, an electric or electronic drive unit may be used.

[0004] Also, electro-mechanical wheel brakes are known which typically have an electric or electronic drive unit, which interacts with a mechanism or a gearbox. On the output side, a brake unit can be arranged, which can comprise, for example, a brake part with a friction component. The friction component can be pressed onto a brake disc or drum by means of translational movement, for example. This can cause a desired braking of the motor vehicle in operation.

[0005] The associated functions for controlling the motor drive unit are typically foreseen in a corresponding brake control unit (ECU). For example, a force regulator can be provided here, which can generate a set point for the actuator speed or speed based on a specified target force, which can correspond to a driver's brake request, in order to apply a clamping force to the assigned wheel brake.

[0006] The availability of the brake control unit and the corresponding motor drive unit is therefore of great importance, as the wheel brakes are one of the safety-relevant functions of the motor vehicle. This can lead to redundant design of essential components or functions. In this sense, redundancy means the additional presence of functionally identical or comparable components or functions, i.e. for example the presence of at least two connections, e.g. data or communication lines. This means that in the event of failure of a component or system, safe operation of the braking system as a whole can continue to be guaranteed.

[0007] In this way, if the braking system fails, the motor vehicle should still be able to be reliably brought to a standstill and kept there. The requirements for highly automated driving systems can be even higher than for current ones.

[0008] In this context, it must also be taken into account that, for example, a failure of the power supply or the on-board electrical system may no longer make it possible to operate such a motor vehicle brake.

[0009] Additionally, motor vehicles today may implement more than one boardnet, for example two or multiple boardnets within one vehicle.

[0010] To make use of the presence of more than one boardnet and to ensure a safe operation of the braking system is therefore an essential task of the present invention.

[0011] This object is achieved by the present invention by a brake system, in particular for motor vehicles, and a method for the breaking of wheels, in particular of motor vehicles, according to one of the independent claims. Preferred embodiments and further features of the invention can be found in the respective dependent claims.

[0012] In a first aspect, the invention therefore provides a brake system for a motor vehicle comprising: a first braking system, an ECU modulator connected to a first power supply inlet of a first boardnet, an ECU actuator connected to a second power supply inlet of a second boardnet, a first electronic switch and a second electronic switch each connected between the ECU modulator and the ECU actuator, wherein the ECU modulator and the ECU actuator each have a first protection interface, and a first cross connection, connecting a first connecting line and a second connecting line with each other, wherein the first electronic switch and the second electronic switch are arranged in series within the first cross connection, and wherein a motor drive unit can be connected to the second connecting line.

[0013] The brake system allows to operate a motor drive unit with power from a first boardnet and / or from a second boardnet. The brake system according to the invention therefore can be used advantageously for motor vehicles comprising multiple boardnets.

[0014] One boardnet can be configured being a high voltage boardnet, such as one using a 48 V battery, that may be used for some vehicle functions, such as starting the vehicle, while a second boardnet, such as a 12 V system, can be used for other vehicle functions. In accordance with some embodiments of the invention, a DC-DC converter can be used to connect the boardnets to one another. However, a brake system according to the invention is not limited to this configuration only. In other configurations, both boardnets may use the same voltage systems.

[0015] The brake system according to the invention may comprise a first electrohydraulic braking system with at least one hydraulically operated wheel brake. The electrohydraulic braking system may have hydraulically operated wheel brakes, which may act on the wheels of at least one of the axles of the motor vehicle.

[0016] The wheel brakes may be hydraulically operated disc brakes or hydraulically operated drum brakes, for example. The wheel brakes are applied in active operation of the brake system with a hydraulic brake pressure, which is translated by the wheel brakes into a braking force acting on the respective vehicle wheels assigned to the wheel brakes based on a brake control signal received at a first electronic control unit (ECU) for the first braking system.

[0017] The first braking system may comprise an ECU actuator, configured to generate hydraulic brake pressure based on the brake control signal received by the first ECU. The first braking system may also comprise an ECU modulator, configured to modulate the hydraulic pressure from the ECU actuator to the brakes. Brake fluid for the wheel brakes can be provided from a first fluid reservoir.

[0018] The brake system according to the invention may further comprise a second braking system, which could be configured as being also an electrohydraulic or an electro-mechanical braking system. The electro-mechanical braking system may comprise electro-mechanically operated wheel brakes. Electro-mechanically actuation of the wheel brakes can be foreseen at the same or different axles of the motor vehicle, for example, a second axle can be configured with electro-mechanical wheel brakes. The second braking system may control each of the wheel brakes at the corresponding or second axle independently from one-another.

[0019] However, the first braking system may be designed to exchange information with the second braking system. This may be for example actuation information, applied brake pressures or braking forces or other operating information of the respective first and second braking systems.

[0020] In a normal operation mode the first electrohydraulic braking system may receive the brake control signal from a vehicle controller.

[0021] In case of an electrohydraulic braking system, the actuator may include an electric motor to drive a piston within a hydraulic cylinder. The piston is connected to the electric motor in such a way that a rotation of a drive shaft of the motor translates the piston within the cylinder. Therefore, the power of the electric motor is translated into a translation of the pressure piston in the hydraulic cylinder, whereby a brake fluid located in the hydraulic cylinder can be pressed with a pressure. The rotational position of a rotor of the electric motor and thus the current position of the pressure piston in the hydraulic cylinder can be monitored by a motor position sensor.

[0022] The hydraulic cylinder of the first actuator may also hydraulically connected to the ECU modulator, wherein between the ECU modulator and the hydraulic cylinder of the first actuator a currentless closed pressure supply valve, i.e. a pressure feed valve (PFV), can be arranged. The pressure supply valve can therefore establish or interrupt a hydraulic connection between the ECU actuator and the ECU modulator. Therefore, the wheel brakes are applied in active operation of the first electrohydraulic brake system with a hydraulic brake pressure, which is translated by the wheel brakes into a braking force acting on the respective vehicle wheels assigned to the wheel brakes.

[0023] The ECU modulator portion of the first braking system may have a currentless open intake valve and a currentless closed exhaust valve per connected hydraulically operated wheel brake. The exhaust valves are designed to establish or interrupt a hydraulic connection between the wheel brakes and the fluid reservoir, so that a hydraulic brake pressure applied in the wheel brakes can be reduced via the exhaust valves. At the same time, by selectively opening and closing the intake valves, the hydraulic brake pressure applied in wheel brakes can be modulated from the applied inlet pressure.

[0024] A braking input system may be included in the first braking system or may be separate from the first braking system. The braking input system may include a master cylinder with a movable cylinder piston mounted in the master cylinder. The cylinder piston can be moved by actuating an actuation pedal connected to the cylinder piston in the master cylinder, or a brake fluid located in the master cylinder can be pressurized with a hydraulic pressure. The hydraulic pressure generated here can be detected by a pressure sensor. Furthermore, the displacement distance of the cylinder piston can be determined by a displacement sensor. The master cylinder may be hydraulically connected initially to a pedal feeling simulator. A brake control signal may be generated by a vehicle controller based on the movement of the pedal. The brake control signal can be sent to the control unit ECU.

[0025] The braking input system may also be connected to the first braking system with a master cylinder valve. The master cylinder valve is normally closed and is opened to provide brake control in a fallback mode for the first braking system. In a normal operation mode the first braking system may operate in a by-wire manner based on the brake control signal. Alternatively, the braking input system can be independent of the first braking system and still provide the brake control signal to the first electronic control unit ECU.

[0026] The first electronic control unit ECU may also be connected to a parking brake system which includes a parking brake switch, so that when the parking brake switch is pressed, a corresponding information can be processed by the first control unit ECU. The first control unit ECU may be designed to transmit a corresponding control information for activating the parking brake function.

[0027] In case of electro-mechanical actuation of the wheel brakes, the wheel brakes may comprise electro-mechanically operated disc brakes or electro-mechanically operated drum brakes, for example. Here, the wheel brakes may include an electrically driven motor unit, also referred to as an actuator.

[0028] In accordance with the invention, the ECU modulator may be connected to the first power supply inlet of the first boardnet, and the ECU actuator may be connected to the second power supply inlet of the second boardnet. The first electronic switch and the second electronic switch each may be connected between the ECU actuator and the ECU modulator, wherein the ECU actuator and the ECU modulator each may have an additional first protection interface.

[0029] The first electronic switch and the second electronic switch may be arranged in series in the first cross connection, which may connect the first connecting line and the second connecting line with each other. In this way, the cross connection between the first and second connecting line can be switched on (“activated”) or switched off (“deactivated”) to electrical separate both connecting lines.

[0030] Multiple interfaces or actuators can be provided for the ECU modulator and / or the ECU actuator.

[0031] For example, the braking system may comprise at least one of

[0032] - a motor drive interface for connecting and / or controlling an actuator,

[0033] - an actuation interface or

[0034] - a power control microprocessor interface.

[0035] Each may be electrically connected to the second connecting line, thereby providing a direct power link to the second boardnet. The motor drive interface can be used for connecting and / or controlling the motor drive unit of an electrohydraulic or the electro-mechanical braking system, respectively.

[0036] In addition, the braking system may comprise further at least one of

[0037] - a power control microprocessor interface or

[0038] - a modulation interface.

[0039] Each may be electrically connected to the first connecting line, thereby providing a direct power link to the first boardnet.

[0040] It should be understood that these kinds of interfaces are only mentioned as examples, and other interfaces are possible. Also, the interfaces could be electrically connected to the first or the second connecting line, or the first or second boardnet, respectively.

[0041] This configuration allows the first electronic switch and the second electronic switch to control the electric power supplied to the motor drive unit as well as the other interfaces. In case of activations of both electronic switches, power can be provided to the motor drive interface and thus to the motor drive unit. The first protection interface may be arranged in the first connecting line and the second connecting line each. These protection interfaces may both be used for short circuit detection for reverse current protection by monitoring a voltage drop across the protection interface. Thus, these protection interfaces may prevent coupling of both power input when any of the electronic switches are activated. The protection interfaces may have the same predetermined threshold voltage drop or they may have different predetermined threshold voltage drop as one another.

[0042] In a preferred embodiment of the invention, a current sense module may be located in the first cross connection. The current sense may be located at a position between the first protection interface of the first circuit and the first electronic switch. A signal of the current sense module may be used to identify and check the current in the cross connection.

[0043] In just another preferred embodiment of the invention, a second cross connection may be arranged to connect the first connecting line and the second connecting with each other. This second cross connection therefore may be arranged, at least partly, in parallel to the first cross connection. In accordance with one embodiment, the second cross connection may comprise a third and a fourth electronic switch. Activation of the third and fourth electronic switches may provide current limited power to the motor drive interface, the actuation interface and / or the power control microprocessor interface.

[0044] For this reason, a current limitation module may be located in the second cross connection. The current limitation module may be located at a position between the electronic switch of the second cross connection and the interfaces. The current limitation module may be an active or passive resistor in the second cross connection, for example.

[0045] This arrangement advantageously prevents excessive current draw on first power supply inlet of the first boardnet by charging up the motor drive interface or other components at the second connecting line before the electronic switches of the first cross connection are activated. The third and fourth electronic switches of the second cross connection may be activated to support for example an actuation interface or a power control microprocessor interface until the electronic switches of the first cross connection are activated.

[0046] In a preferred embodiment of the invention, all electronic switches of the first and second cross connection may be activated when power supply of the second boardnet drops below a predefined voltage threshold in order to allow power supply of the first boardnet to supply the interfaces of the second connecting line, for example a motor drive interface.

[0047] According to a further preferred embodiment of the invention, the second cross connection may be coupled directly to the first cross connection. In this embodiment, the second cross connection may be electrically connected to the first cross connection at a position between the first electronic switch and the second electronic switch.

[0048] This embodiment allows to save one electronic switch. The current limitation module may be located at a position between the connecting point of the first cross connection and the only one electronic switch of the second cross connection.

[0049] In this arrangement, activations of the first and second electronic switch of the first cross connection may advantageously provide power to the motor drive interface. Also, an over current detection may be included.

[0050] Activations of the second electronic switch of the first cross connection and the third electronic switch of the second cross connection may advantageously provide current limited power to the corresponding interfaces. Also, a current limitation is possible due to the current limitation module. This arrangement may prevent excessive current draw of the first boardnet by charging up the interfaces, for example a motor drive interface, before the first electronic switch of the first cross connection is activated. The activation of the second electronic switch of the first cross connection and the third electronic switch of the second cross connection may advantageously support the actuation interface and / or the power control microprocessor interface before the first electronic switch of the first cross connection is activated.

[0051] In a preferred embodiment of the invention, the first, the second and the third electronic switches of this arrangement may be activated when power supply of the second boardnet drops below a predefined voltage threshold in order to allow power supply of the first boardnet to supply the interfaces of the second connecting line.

[0052] In a further aspect, the invention also provides a method for the breaking of wheels of a motor vehicle to be carried out on a braking system as described above.

[0053] In yet another aspect, the invention also provides a motor vehicle, comprising at least one braking system as described above.

[0054] The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.

[0055] Further details of the invention can be found in the description of the embodiments shown and the attached claims.

[0056] The drawings show:

[0057] Fig. 1 a partial schematic representation of a first embodiment of an exemplary braking system,

[0058] Fig. 2 a partial schematic representation of a first embodiment of an actuator and modulator arrangement of the exemplary braking system, Fig. 3 a partial schematic representation of a second embodiment of an actuator and modulator arrangement of the exemplary braking system,

[0059] Fig. 4 a partial schematic representation of a third embodiment of an actuator and modulator arrangement of the exemplary braking system,

[0060] Fig. 5 a partial schematic representation of a fourth embodiment of an actuator and modulator arrangement of the exemplary braking system, and

[0061] Fig. 6 a partial schematic representation of a fifth embodiment of an actuator and modulator arrangement of the exemplary braking system.

[0062] In the following, similar or identical characteristics are marked with the same reference signs.

[0063] Fig. 1 shows a modular vehicle brake system 102 for a motor vehicle 100 with a first electrohydraulic braking system 110 and a second braking system (not shown). The vehicle 100 may implement multiple boardnets 106, 108 within a vehicle. The brake system 102 for a motor vehicle 100 comprises: a first electrohydraulic braking system 110, an ECU modulator 118 connected to a first power supply inlet of a first boardnet 108, an ECU actuator 116 connected to a second power supply inlet of a second boardnet 106, a first electronic switch 155 and a second electronic switch 156 each connected between the ECU modulator 118 and the ECU actuator 116, wherein the ECU modulator 118 and the ECU actuator 116 each have a first protection interface 157, 158, and a first cross connection 141 , connecting a first connecting line 107 and a second connecting line 109 with each other, wherein the first electronic switch 155 and the second electronic switch 156 are arranged in series within the first cross connection 141 , and wherein a motor drive unit can be connected to the second connecting line 109.

[0064] The boardnet 106 may be used for some vehicle functions, such as starting the vehicle, for example. The second boardnet 108 can be used for other vehicle functions. In one embodiment of the invention, the boardnet 106 could be a high voltage boardnet using a 48V battery, and the second boardnet 108 could be a 12V system.

[0065] A DC-DC converter can be used to connect the boardnets to one another in case of an 48V input in one boardnet.

[0066] In one embodiment of the invention, the first electrohydraulic braking system 110 may be connected to the second boardnet 108.

[0067] Fig. 1 schematically illustrates the mechanical structure and connections for a normal and fallback operating mode of the first braking system 1 10 while Figures 2-6 illustrate variations of the power supply architecture that provide redundant power supply which may be used for the first braking system 110.

[0068] The first electrohydraulic braking system 110 has hydraulically operated wheel brakes 112a and 112b, which act on the wheels of first axle 104 of the motor vehicle 100. The wheel brakes 112a and 112b may be hydraulically operated disc brakes for example. The wheel brakes 112a and 112b are applied in active operation of the brake system 110 with a hydraulic brake pressure, which is translated by the wheel brakes 112a and 112b into a braking force acting on the respective vehicle wheels assigned to the wheel brakes 112a and 112b based on a brake control signal received at a first electronic control unit ECU 114 for the first braking system 110.

[0069] The first braking system 110 has an ECU actuator 116 (“ECU1 actuator”) to generate hydraulic brake pressure based on the brake control signal received by the first electronic control unit ECU 114. The first braking system 110 has an ECU modulator 118 (“ECU1 modulator”) to modulate the hydraulic pressure from the ECU actuator 116 to the wheel brakes 112a and 112b. Brake fluid for the wheel brakes 112a and 1 12b is provided from a first fluid reservoir 120.

[0070] However, the first braking system 110 is designed to exchange information with the second braking system 140. This may be for example actuation information, applied brake pressures or braking forces or other operating information of the respective first and second braking systems 110, 140. The second braking system 140 may have electro-hydraulic or electro-mechanical actuation of the wheel brakes at a second axle of the vehicle. The second braking system 140 may control each of the wheel brakes at the second axle independently from one-another.

[0071] In a normal operation mode, the first electrohydraulic braking system 110 receives the brake control signal from the vehicle controller 128. The ECU actuator 116 includes a motor 122 and a drive a piston 124 within a hydraulic cylinder 126. The piston 124 is connected to the motor 122 in such a way that a rotation of a drive shaft of the motor 122 translates the piston 124 within the cylinder 126. Therefore, the electric motor 122 is translated into a translation of the pressure piston 124 in the hydraulic cylinder 126, whereby a brake fluid located in the hydraulic cylinder 126 can be pressed with a pressure. The rotational position of a rotor of the electric motor 122 and thus the current position of the pressure piston 124 in the hydraulic cylinder 126 is monitored by a motor position sensor.

[0072] The hydraulic cylinder 126 of the ECU actuator 116 is also hydraulically connected to the ECU modulator 118, wherein between the ECU modulator 118 and the hydraulic cylinder 126 of the first actuator 116 a currentless closed pressure supply valve 130, i.e., a pressure feed valve (PFV) is arranged. The pressure supply valve 130 can therefore establish or interrupt a hydraulic connection between the ECU actuator 116 and the ECU modulator 118.

[0073] Therefore, the wheel brakes 112a and 112b are applied in active operation of the first electrohydraulic brake system 110 with a hydraulic brake pressure, which is translated by the wheel brakes 112a and 112b into a braking force acting on the respective vehicle wheels assigned to the wheel brakes 112a and 112b.

[0074] The ECU modulator 118 portion of the first braking system 110 has a currentless open intake valve 132 and a currentless closed exhaust valve 134 per connected hydraulically operated wheel brake 112a and 112b. The exhaust valves 134 are designed to establish or interrupt a hydraulic connection between the wheel brakes 112a and 112b and the fluid reservoir 120, so that a hydraulic brake pressure applied in the wheel brakes 112a and 112b can be reduced via the exhaust valves 134. At the same time, by selectively opening and closing the intake valves 132, the hydraulic brake pressure applied in wheel brakes 112a and 112b can be modulated from the applied inlet pressure.

[0075] A braking input system 180 may be included in the first braking system 110 or may be separate from the first braking system 110. The braking input system 180 includes a master cylinder 181 with a movable cylinder piston 182 mounted in the master cylinder 181. The cylinder piston 182 can be moved by actuating an actuation pedal 183 connected to the cylinder piston 182 in the master cylinder 181 , or a brake fluid located in the master cylinder 181 can be pressurized with a hydraulic pressure. The hydraulic pressure generated here is detected by a pressure sensor 184. Furthermore, the displacement distance of the cylinder piston 182 is determined by a displacement sensor. The master cylinder 181 is hydraulically connected initially to a pedal feeling simulator 186. A brake control signal is generated by a vehicle controller 108 based on the movement of the pedal 183. The brake control signal is sent to the first control unit 114.

[0076] The braking input system 180 is also connected to the first braking system 110 with a master cylinder valve 188. The master cylinder valve 188 is normally closed and is opened to provide brake control in a fallback mode for the first braking system 110. In a normal operation mode, the first braking system 110 operates in a by-wire manner based on the brake control signal. Alternatively, the braking input system 180 can be independent of the first braking system 110 and still provide the brake control signal to the first control unit. The first control unit 114 is also connected to a parking brake system 190 which includes a parking brake switch 192, so that when the parking brake switch 192 is pressed, a corresponding information can be processed by the first control unit 114. The first control unit 114 is then designed to transmit a corresponding control information for activating the parking brake function.

[0077] A brake system 102 in accordance with the invention may comprise more than one electronic control units ECUs. For example, a first electronic control unit 114 may provide a first braking system on a first axle 104, and a second electronic control unit may provide a second braking system on a rear axle. Further embodiments of brake systems 102 in accordance with the invention may comprise separate electronic control units to provide braking per wheel, for example. In the following examples, the figures shown only refer to a first braking system 1 10 for the sake of clarity. It should be understood that the brake system 102 also may comprise more than one brake system and / or more than one ECU actuator 116 and / or more than one ECU modulator 118. In just another embodiment of the invention, the first electronic control unit 114 may also include braking system for rear axle.

[0078] Fig. 2 illustrates a partial schematic view of a first embodiment of a power supply architecture 150 between the ECU modulator 118 and the ECU actuator 116.

[0079] In Fig. 2 as well as in the following figures, only components of the electronic circuits of the ECU modulator 118 and the ECU actuator 116 relevant to the invention are shown.

[0080] The first braking system 110 comprises a first redundant power supply architecture 150 for two independent boardnets 106, 108 with cross connections 141 , 142 to support supply from only one power input 152 for the brake system 102.

[0081] The first power supply architecture 150 includes a first circuit MOD 118a and a second circuit ACT 116a. The first circuit MOD 118a (“Modulator”) belongs to the ECU modulator 118 and the second circuit ACT 116a (“Aktuator”) belongs to the ECU actuator 116. Both the first circuit MOD 118a and second circuit ACT 116a can be combined and included into the electronic control unit ECU 114.

[0082] The power input 152 for the electronic braking system 110 is split into a first power supply inlet 108a (“Power 1”) for the circuit MOD 118a of the ECU modulator 118 and a second power supply input 106a (“Power 2”) for the circuit ACT 116a of the ECU actuator 116. The ECU actuator 116 is therefore connected to the power supply inlet 106a of the second boardnet 106, and the ECU modulator 1 18 is connected to the second power supply inlet 108a of the first boardnet 108.

[0083] The first electronic switch 155 and the second electronic switch 156 are connected between the ECU actuator 116 and the ECU modulator 118, wherein the ECU actuator 116 and the ECU modulator 118 each have a first protection interface 157, 158. The electronic switches 155, 156 are arranged in series in the first cross connection 141 which connects the first connecting line 109 and the second connecting line 107 with each other.

[0084] Multiple interfaces or actuators can be provided for the circuit ACT 116a and circuit MOD 118a. As it can be seen from Fig. 2, the exemplary braking system 110 comprises:

[0085] - a motor drive interface 170 for connecting and / or controlling the motor drive unit,

[0086] - an actuation interface 171 , and

[0087] - a power control microprocessor interface 172.

[0088] All interfaces 170, 171 , 172 are electrically coupled to the second connecting line 109, thereby providing a direct power link to the second boardnet 106.

[0089] In addition, the braking system 110 also comprises:

[0090] - a power control microprocessor interface 173 and

[0091] - a modulation interface 174. All interfaces 173, 174 are electrically coupled to the first connecting line 107, thereby providing a direct power link to the first boardnet 108.

[0092] It should be understood that these interfaces and actuators are only shown as examples, and other embodiments and arrangements are still possible. For example, the interfaces may be valves for the ECU modulator 118 or ECU actuator 116.

[0093] The shown configuration of the power supply architecture 150 allows the first electronic switch 155 and the second electronic switch 156 to control the electric power supplied to the motor drive interface 170 as well as the other interfaces 171 , 172. In case of activations of both electronic switches 155, 156, sufficient power can be provided to the motor drive interface 170 and thus to the motor drive unit.

[0094] The first protection interfaces 157, 158 are arranged in the first connecting line 107 and the second connecting line 109. These protection interfaces 157, 158 are configured with reverse current protection. In this manner, these protection interfaces 157, 158 prevent coupling of both power supply inputs 106a, 108a when any of the electronic switches are activated.

[0095] In a preferred embodiment of the invention, as can be seen from Fig. 2, a current sense 161 is located in the first cross connection 141. The current sense 161 is located at a position between the first protection interface 157 of the circuit MOD 118a and the first electronic switch 155.

[0096] In the exemplary embodiment of the invention shown in Fig. 2, a second cross connection 142 is arranged to connect the first connecting line 109 and the second connecting line 107 with each other. This second cross connection 142 is arranged in parallel to the first cross connection 141 , thereby providing a second electrical connection between the connecting lines 107, 109.

[0097] In accordance with the embodiment shown in Fig. 2, the second cross connection

[0098] 142 comprises a third and a fourth electronic switch 159, 160. Activation of the third and fourth electronic switches 159, 160 provides current limited power to the motor drive interface 170, the actuation interface 171 and / or the power control microprocessor interface 172.

[0099] For this reason, a current limitation module 162 is provided in the second cross connection 142. The current limitation module 162 is located at a position between the third electronic switch 159 and the motor drive interface 170, the actuation interface 171 and / or the power control microprocessor interface 172, respectively.

[0100] This arrangement advantageously prevents excessive current draw on first power supply inlet of the first boardnet 108 by charging up the motor drive interface 170 before the electronic switches 155, 156 of the first cross connection 141 are activated. The third and fourth electronic switches 159, 160 of the second cross connection 142 may be activated to support for example the actuation interface 171 or the power control microprocessor interface 172 until the electronic switches 155, 156 of the first cross connection 141 are activated.

[0101] In a preferred embodiment of the invention, all electronic switches 155, 156, 159, 160 of the first and second cross connection 141 , 142 are activated when power supply of the second boardnet 106 drops below a predefined voltage threshold in order to allow power supply of the first boardnet 108 to supply the motor drive interface 170 or the other interfaces 171 , 172.

[0102] In the exemplary embodiment, a communication link 119 is provided to connect the power control microprocessor interface 172 and the power control microprocessor interface 173 with each other, thereby enabling communication between these components.

[0103] In Figures 2-6, monitoring interfaces 143 and diagnostics interfaces 144 are shown. One skilled in the art would be able to determine optimal monitoring / diagnostic interface locations based on the circuit layout, power, load, etc. for a specific circuit arrangement. The monitoring interfaces 143 for protection interfaces 157, 158 include check for reverse current flow into boardnet and power supply inlet monitoring.

[0104] The diagnostics interfaces 144 will check for proper electronic switch 155 / 156 / 159 / 160 / 154 / 254 activation / deactivation. The diagnostics interface 144 also will check for proper electronic switch 354a / 354b activation / deactivation.

[0105] According to a further preferred embodiment of the invention, the second cross connection 142 can be coupled directly to the first cross connection 141 . Fig. 3 shows a partial schematic representation of a corresponding second embodiment of a power supply architecture 250 between the ECU modulator 118 and the ECU actuator 116.

[0106] In this exemplary embodiment, the second cross connection 142 is electrically coupled to the first cross connection 141 at a position between the first electronic switch 155 and the second electronic switch 156. This embodiment allows to save costs, because one electronic switch can be eliminated from the power supply architecture. The functionality remains essentially unchanged. In such an embodiment, the current limitation module 162 can be located at a position between the connecting point of the first cross connection 141 and the remaining electronic switch 159 of the second cross connection 142.

[0107] In this arrangement, activations of the first and second electronic switch 155, 156 of the first cross connection 141 can advantageously provide power to the motor drive interface 170 or the other interfaces 171 , 172. Also, an over current detection is included.

[0108] Activations of the second electronic switch 159 of the first cross connection 141 and the third electronic switch 159 of the second cross connection 142 can advantageously provide current limited power to the motor drive interface 170 or the other interfaces 171 , 172. Also, a current limitation is possible due to position of the current limitation module 162. This arrangement may prevent excessive current draw of the first boardnet 108 by charging up the motor drive interface 170 before the first electronic switch 155 of the first cross connection 141 is activated.

[0109] The activation of the second electronic switch 156 of the first cross connection 141 and the third electronic switch 159 of the second cross connection 142 can advantageously support the actuation interface 171 and / or the power control microprocessor interface 172 before the first electronic switch 155 of the first cross connection 141 is activated.

[0110] In a preferred embodiment of the invention, the first, the second and the third electronic switch 155, 156, 159 of this arrangement can be activated when power supply of the second boardnet 106 drops below a predefined voltage threshold in order to allow power supply of the first boardnet 108 to supply the motor drive interface 170.

[0111] Fig. 4 illustrates a partial schematic view of a third embodiment of a power supply architecture 350 between the ECU modulator 118 and the ECU actuator 116.

[0112] The third power supply architecture 350 also includes a first circuit MOD 118a and a second circuit ACT 116a. The power input 152 for the electronic brake system 110 is also split into a first power supply input 108a for the first circuit MOD 118a and a second power supply input 106a for the second circuit ACT 116a.

[0113] A first electronic switch 155 for the circuit MOD 118a and a second electronic switch 156 for the circuit ACT 116a are also included. The first electronic switch 155 and the second electronic switch 156 both have two connections between power control microprocessor interface 172 and power control microprocessor interface 173. The microprocessor can be part of a corresponding chipset, which may comprise additional electronic components such as other microprocessors, power control unit and others.

[0114] The circuit ACT 1 16a and the circuit MOD 118a can be configured as different interfaces. It should be understood the that electronic switch operation as disclosed in this document works independent from the microprocessor interfaces and chipsets.

[0115] Thus, multiple interfaces or actuators can be provided for the circuit ACT 116a and circuit MOD 118a. In the exemplary embodiment, a motor drive interface 170, an actuation interface 171 and the power control microprocessor interface 172 are provided for the circuit ACT 116a, and the power control microprocessor interface 173 and a modulation interface 174 for the circuit MOD 118a.

[0116] The first and second boardnet 106, 108 may require two series diodes from the first boardnet 106 and two series protection interfaces from the second boardnet 108 to input of Dropout buffer. This may increase the regulator turn-on voltage.

[0117] The circuit MOD 118a has a first protection interface 157 and a second protection interface 154 arranged in series. Likewise, the circuit ACT 116a has a first protection interface 158 and the second protection interface 154 also arranged in series.

[0118] The first protection interfaces 157, 158 and the second protection interface 154 may both be used for short circuit detection for reverse battery protection by monitoring a voltage drop across the diode. That is if the voltage drop is below a predetermined threshold this will indicate that a short is present.

[0119] The first protection interface 157 and the second protection interface 154 may have the same predetermined threshold voltage drop or may have different predetermined threshold voltage drop as one another. The second protection interface 154 may by a MOSFET as shown in Fig. 4.

[0120] In the shown embodiment, the second protection interface 154 is located in series between the electronic switches 155, 156 and the modulation interface 174. The modulation interface 174 may be for example control an actuator for the modulator valve(s). In Fig. 4 the second protection interface 154 is also located in series with the first protection interface 157 of the circuit MOD 118a.

[0121] Fig. 5 illustrates a partial schematic view of a fourth embodiment of a power supply architecture 450. The braking system 110 has a second redundant power supply architecture 450 for two independent boardnets 106, 108 with cross connection 141 to support supply from only one power supply input 106a, 108a for the braking system 110. The power supply architecture 450 operates in a similar manner as discussed in Fig. 4.

[0122] The second electronic switch 254 of the embodiment of Fig. 5 is still located in series between the first protection interface 158, the electronic switches 155, 156 and the modulation interface 174. The second electronic switch 254 may by a MOSFET as shown in Figure 3.

[0123] Fig. 6 illustrates a partial schematic view of a fifth embodiment of a power supply architecture 550. The corresponding braking system 1 10 has a second redundant power supply architecture 550for two independent boardnets 106, 108 with cross connection 141 to support supply from only one power supply input 106a, 108a for the braking system 110. The power supply architecture 550 operates in a similar manner as discussed in Fig. 5.

[0124] The second electronic switch 254 of the embodiment as shown in Fig. 4 is replaced with two smaller electronic switches 354a and 354b. In Fig. 6, these electronic switches 354a and 354b are located in parallel with the electronic switches 155, 156 and the modulation interface 174.

[0125] In the power supply architectures, voltage can be measured at different positions.

[0126] The redundant power supply architectures 150, 250, 350, 450, 550 will be able to supply all functions from two or more power inputs. A single point failure on one power supply line of one boardnet in the ECU will not affect the other independent boardnet. This special power supply architectures solve also the problem without cross effects. The cross connection 141 , 142 monitoring prevents no activation during short circuit events or high current events. This special cross connection will be solving the problem with the very small cross current between the independent boardnets.

[0127] The foregoing description shall be interpreted as illustrative and not be limited thereto. One of ordinary skill in the art would understand that certain modifications may come within the scope of this disclosure. Although the different non-limiting embodiments are illustrated as having specific components or steps, the embodiments of this disclosure are not limited to those combinations. Some of the components or features from any of the non-limiting embodiments may be used in combination with features or components from any of the other non-limiting embodiments. For these reasons, the appended claims should be studied to determine the true scope and content of this disclosure.

[0128] List of Reference Numerals

[0129] 100 motor vehicle

[0130] 102 brake system

[0131] 104 first axle

[0132] 106 boa rd net

[0133] 106a power supply inlet

[0134] 107 first connecting line

[0135] 108 boa rd net

[0136] 108a power supply inlet

[0137] 109 second connecting line

[0138] 110 electrohydraulic braking system

[0139] 112a, 112b wheel brake

[0140] 114 electronic control unit ECU

[0141] 116 ECU actuator

[0142] 116a circuit ACT

[0143] 118 ECU modulator

[0144] 118a circuit MOD

[0145] 119 communication link

[0146] 120 fluid reservoir

[0147] 122 motor

[0148] 124 piston

[0149] 126 hydraulic cylinder

[0150] 128 vehicle controller

[0151] 130 pressure supply valve

[0152] 132 intake valve

[0153] 134 exhaust valve 140 braking system

[0154] 141 first cross connection

[0155] 142 second cross connection

[0156] 143 monitoring interface

[0157] 144 diagnostic interface

[0158] 150 power supply architecture

[0159] 152 power input

[0160] 154 second protection interface

[0161] 155 electronic switch

[0162] 156 electronic switch

[0163] 157 first protection interface

[0164] 158 first protection interface

[0165] 159 electronic switch

[0166] 160 electronic switch

[0167] 161 current sense

[0168] 162 current limitation

[0169] 163 third protection interface

[0170] 170 motor drive interface

[0171] 171 actuation interface

[0172] 172 power control microprocessor interface

[0173] 173 power control microprocessor interface

[0174] 174 modulation interface

[0175] 180 braking input system

[0176] 181 master cylinder

[0177] 182 piston

[0178] 183 actuation pedal

[0179] 184 pedal travel sensor 186 pedal feeling simulator

[0180] 188 master cylinder valve

[0181] 190 parking brake system

[0182] 192 parking brake switch 250 power supply architecture

[0183] 254 electronic switch

[0184] 310 brake system

[0185] 350 power supply architecture

[0186] 354a, 354b electronic switch 450 power supply architecture

[0187] 550 power supply architecture

Claims

Patent Claims1 . A brake system (102) for a motor vehicle comprising: a first braking system (110), an ECU modulator (118) connected to a first power supply inlet (108a) of a first boardnet (108), an ECU actuator (116) connected to a second power supply inlet (106a) of a second boardnet (106), a first electronic switch (155) and a second electronic switch (156) each connected between the ECU modulator (118) and the ECU actuator (116), wherein the ECU modulator (118) and the ECU actuator (116) each have a first protection interface (157, 158), and a first cross connection (141 ), connecting a first connecting line (107) and a second connecting line (109) with each other, wherein the first electronic switch (155) and the second electronic switch (156) are arranged in series within the first cross connection (141 ), and wherein a motor drive unit can be connected to the second connecting line (109).

2. The brake system (102) as claimed in claim 1 , characterized in that the brake system (102) comprises at least one electrohydraulic braking system (110) with hydraulically operated wheel brakes.

3. The brake system (102) as claimed in any of the preceding claims, characterized in that the brake system (102) comprises at least one electro-mechanical braking system with electro-mechanically operated wheel brakes.

4. The brake system (102) as claimed in any of the preceding claims, characterized in that the first protection interfaces (157, 158) are configured to include a reverse current protection.

5. The brake system (102) as claimed in any of the preceding claims, characterized in that the braking system comprises at least one of- a motor drive interface (170) for connecting and / or controlling the motor drive unit,- an actuation interface (171 ) or- a power control microprocessor interface (172) each are electrically connected to the second connecting line (109).

6. The brake system (102) as claimed in any of the preceding claims, characterized in that the braking system comprises at least one of- a power control microprocessor interface (173) or- a modulation interface (174), each are electrically connected to the first connecting line (107).

7. The brake system (102) as claimed in the preceding claim, characterized in that a third protection interface (163) is located at a position between the first power supply inlet (108a) of the first boardnet (108) and the power control microprocessor interface (173).

8. The brake system (102) as claimed in any of the preceding claims 5 and 6, characterized in that a fourth protection interface (164) is located at a position between the first power supply inlet (108a) of the first boardnet (108) and the modulation interface (174), wherein the fourth protection interface (164) is preferably configured to include reverse current protection.

9. The brake system (102) as claimed in any of the preceding claims, characterized in that a current sense (161 ) is located in the first cross connection (141 ), preferably at a position between the first protection interface (157) and the first and second electronic switches (155, 156).

10. The brake system (102) as claimed in any of the preceding claims, characterized in that a second cross connection (142) is arranged to connect the first connecting line (107) and the second connecting line (109) with each other.

11. The brake system (102) as claimed in the precedent claim, characterized in that the second cross connection line (142) comprises a third and a fourth electronic switch (159, 160).

12. The brake system (102) as claimed in any of the preceding claims, characterized in that a current limitation module (162) is located in the second cross connection (142), preferably at a position between the third electronic switch (159) and the motor drive interface (170), the actuation interface (171 ) and / or the power control microprocessor interface (172), respectively.

13. The brake system (102) as claimed in any of the preceding claims, characterized in that the second cross connection (142) is coupled to the first cross connection (141) at a position between the first electronic switch (155) and the second electronic switch (156).

14. A method for the breaking of wheels to be carried out on a brake system (102) as claimed in any of the preceding claims.

15. A motor vehicle, comprising at least one brake system (102) as claimed in any of the preceding claims 1-13.

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