KR20200130956A - Circuit for protecting Electronic controller unit, Electronic controller unit, and System for assisting Steering - Google Patents

Abstract

The present disclosure relates to an ECU protection circuit, an electronic control unit and a steering assist system. Specifically, the ECU protection circuit according to the present disclosure includes: a Zener diode that allows a reverse current to flow when the phase voltage of a steering motor is more than a preset breakdown voltage; and a first switch that is turned on when the reverse current is applied and allows a first current to flow; and a second switch that is turned on when the first current flows and allows a second current to flow so that voltage supplied from a battery can be conducted to a PCO switch. The PCO switch is turned on when the supplied voltage is applied.

Description

ECU protection circuit, electronic control unit, and steering assistance system TECHNICAL FIELD [Circuit for protecting Electronic controller unit, Electronic controller unit, and System for assisting Steering]

The present disclosure relates to an ECU protection circuit, an electronic control unit and a steering assistance system.

The vehicle steering assistance system is a system that assists the driver to change the driving direction of the vehicle at the will of the driver, and is a system that assists the vehicle to operate more easily by generating a steering assist force for the driving direction desired by the driver.

Such a steering assist system is implemented by a hydraulic power assist steering device (HPS) and an electronic power assist steering device (EPS: Electric Power Steering Apparatus).

In recent steering assistance systems, in case a specific configuration included in the system fails, a redundant system with the same configuration as a specific configuration is applied, and fail safety is implemented based on this redundant system. Are doing.

However, when fail safety is implemented based on the redundant system, a back electromotive force may be generated from the steering motor included in the steering assistance system, and in this case, an electronic control unit that controls the steering motor by the back electromotive voltage. There is a problem that the (Electronic controller unit) may be damaged.

Therefore, when a counter electromotive voltage is generated in the steering motor, a technique for effectively preventing this is required.

Against this background, the present disclosure aims to provide an ECU protection circuit, an electronic control unit, and a steering assistance system capable of preventing a counter electromotive voltage of a steering motor while implementing fail safety based on a redundant system.

In addition, the present disclosure is intended to provide an ECU protection circuit, an electronic control unit, and a steering assist system capable of protecting the ECU by effectively preventing the back electromotive voltage of the steering motor using a simple circuit.

In addition, the present disclosure is to provide an ECU protection circuit, an electronic control unit, and a steering assist system that provide driving stability by implementing fail safety more stably.

In order to solve the above-described problem, in one aspect, the present disclosure is a PCO (Phase Cut Off) switch protection circuit, one end is connected to the steering motor, the phase voltage of the steering motor is a preset break down voltage In case of abnormality, a Zener diode that allows a reverse current to flow, and one end is connected to the other end of the Zener diode, and turns on when a reverse current is applied, so that the first switch and one end are connected to the other end of the first switch. And a second switch that is connected and turned on when the first current flows, so that the second current flows and the supply voltage of the battery is conducted to the PCO switch, but the reverse current flows from the steering motor to the Zener diode, and the first current is , Flows from one end of the second switch to the other end of the first switch, and the PCO switch provides an ECU protection circuit, characterized in that it is turned on when a supply voltage is applied.

In another aspect, the present disclosure provides a supply voltage switch for conducting a supply voltage of a battery, an inverter outputting a control signal for controlling the operation of a steering motor, and conducting a control signal to the steering motor or supplying a control signal. When a counter electromotive voltage occurs in the PCO (Phase Cut Off) switch, the supply voltage switch, the microcontroller unit (MCU) that controls each of the inverter and the PCO switch, and the steering motor, the supply voltage of the battery is connected to the PCO switch. It provides an electronic control unit comprising an ECU protection that allows the PCO switch to be turned on.

In another aspect, the present disclosure provides a first electronic control unit including a first MCU, a first inverter, and a first PCO switch, and a second electronic control unit including a second MCU, a second inverter, and a second PCO switch. And, a battery for supplying power to the first electronic control unit and the second electronic control unit, a single winding steering motor controlled by the first electronic control unit or the second electronic control unit, and a first electronic control When the control right for controlling the steering motor is transitioned between the unit and the second electronic control unit, if the phase voltage of the steering motor is equal to or higher than the preset reference voltage, the PCO switch included in the electronic control unit to which the control right is transferred It provides a steering assist system including the ECU protection circuit applied to the.

As described above, according to the present disclosure, the present disclosure can provide an ECU protection circuit, an electronic control unit, and a steering assistance system capable of preventing a counter electromotive voltage of a steering motor while implementing fail safety based on a redundant system.

In addition, according to the present disclosure, the present disclosure can provide an ECU protection circuit, an electronic control unit, and a steering assist system capable of protecting the ECU by effectively preventing a counter electromotive voltage of a steering motor using a simple circuit.

In addition, according to the present disclosure, by using a simpler circuit, the present disclosure can provide an ECU protection circuit, an electronic control unit, and a steering assistance system that minimizes the space occupied by elements, contributes to high integration, and minimizes manufacturing costs. have.

In addition, according to the present disclosure, the present disclosure can provide an ECU protection circuit, an electronic control unit, and a steering assist system that provide driving stability by implementing fail safety more stably.

Further, according to the present disclosure, the present disclosure can provide an ECU protection circuit, an electronic control unit, and a steering assistance system capable of efficiently using a battery by applying a circuit optimized for a dark current of a battery.

1 is a block diagram illustrating a steering assistance system according to the present disclosure.
FIG. 2 is a diagram for explaining a phenomenon that occurs when an ECU fails in a steering assistance system according to the present disclosure.
3 is a block diagram schematically showing a first embodiment of a steering assistance system according to the present disclosure.
4 is a block diagram schematically showing a second embodiment of a steering assistance system according to the present disclosure.
5 is a block diagram schematically showing a third embodiment of a steering assistance system according to the present disclosure.
6 is a block diagram schematically showing an ECU protection circuit according to the present disclosure.
7 is a circuit diagram showing a connection relationship between an ECU and an ECU protection circuit and a steering motor according to the present disclosure.
8 is a circuit diagram specifically showing the first embodiment of the ECU protection circuit of FIG. 7.
9 is a circuit diagram specifically showing a second embodiment of the ECU protection circuit of FIG. 7.
10 is a diagram showing a waveform of a supply voltage applied to a PCO switch.
11 is a circuit diagram specifically showing a third embodiment of the ECU protection circuit of FIG. 7.
12 is a diagram showing an embodiment of each of the first switch and the second switch included in the ECU protection circuit of FIG. 7.
13 is a block diagram schematically showing another embodiment of an ECU according to the present disclosure.

Hereinafter, some embodiments of the present disclosure will be described in detail through exemplary drawings. In describing the constituent elements of the present disclosure, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, order, or order of the component is not limited by the term. When a component is described as being "connected", "coupled" or "connected" to another component, the component may be directly connected or connected to that other component, but another component between each component It should be understood that elements may be “connected”, “coupled” or “connected”.

1 is a block diagram illustrating a steering assistance system 100 according to the present disclosure.

Referring to FIG. 1, a steering assistance system 100 according to the present disclosure refers to a system that assists steering a vehicle.

The steering assistance system 100 includes a battery 110, a first electronic controller unit (ECU) 120, a second electronic control unit 130, a steering motor 140, and a sensor 150. Can include.

The battery 110 may supply power to the first ECU 120 and the second ECU 130. Here, the supply power may be a supply voltage or a supply current. That is, supplying the supply power may mean that the supply voltage or supply current is supplied. And, since voltage and current are deeply related by Ohm's law, hereinafter, voltage is applied to a specific configuration, device, etc., and is transmitted, meaning that current flows and is applied to and transmitted to a specific configuration, device, etc. I can.

As an example, the battery 110 is configured as an integral type, so that supply power can be supplied to both the first ECU 120 and the second ECU 130, and supply power to only one electronic control unit in a specific state, When the state changes, it is possible to supply power to other electronic control units.

As another example, the battery 110 is composed of two or more battery modules (not shown), and each battery module is connected to each of the first ECU 120 and the second ECU 130 to supply power supply. However, it is not limited thereto.

Meanwhile, the steering assistance system 100 according to the present disclosure may implement a redundant system including two or more ECUs that output electrical signals to the steering motor 140. For example, the steering assistance system 100 according to the present disclosure implements a redundant system including a first ECU 120 and a second ECU 130.

Here, the first ECU 120 and the second ECU 130 receive steering information from the sensor 150, calculate a control signal for controlling the steering motor 140 based on the steering information, and the calculated control signal May be output to the steering motor 140.

For a specific example, when the driver holds and manipulates the steering wheel, the sensor 150 detects the rotation angle (steering angle) generated by the steering wheel, and inputs steering angle information corresponding thereto to the ECUs 120 and 130, and the ECU Reference numerals 120 and 130 output a control signal based on the received steering angle information.

The ECUs 120 and 130 may include a plurality of components that perform respective functions, such as converting a supply voltage of the input battery 110 and blocking or restarting the supply of a control signal. For example, the first ECU 120 includes a first supply voltage switch 121, a first microcontroller unit (MCU, 122), an inverter 123, and a first PCO (Phase Cut Off). The second ECU 130 includes a switch 124 and the like, and the second supply voltage switch 131, the second MCU 132, the second inverter 133, and the second ECU 130 are the same as the first ECU 120. PCO switch 134 and the like.

The supply voltage switches 121 and 131 may conduct a supply voltage of the battery 110. Specifically, when the supply voltage switches 121 and 131 are turned off, the supply voltage of the battery 110 is cut off, and when the supply voltage switches 121 and 131 are turned on, the supply voltage of the battery 110 is reduced to the ECU 120 , 130).

The inverters 123 and 133 may convert a supply voltage of the battery 110, which is direct current (DC), to alternating current (AC), and apply an alternating voltage to the steering motor 140. Specifically, the inverters 123 and 133 may convert the supply voltage of the battery 110 into AC and apply the AC voltage to each phase of the steering motor 140.

The PCO switches 124 and 134 may conduct or block the AC voltage output from the inverters 123 and 133 to the steering motor 140. Specifically, when the PCO switches 124 and 134 are turned off, the AC voltage is cut off, and when the PCO switches 124 and 134 are turned on, the AC voltage may be applied to each phase of the steering motor 140.

The MCUs 122 and 132 may control turn-on/turn-off of the supply voltage switches 121 and 131, the inverters 123 and 133, and the PCO switches 124 and 134, respectively.

Here, one of the first ECU 120 and the second ECU 130 may operate as a main ECU. For example, when the first ECU 120 operates as a main ECU, the first ECU 120 calculates a control signal and outputs it to the steering motor 140, and the first ECU 120 operates as the main ECU. 2 ECU 130 does not operate. However, the present invention is not limited thereto, and the second ECU 130 may operate as a main ECU.

Meanwhile, both the first ECU 120 and the second ECU 130 may operate as a main ECU. At this time, the two ECUs 120 and 130 divide and output the target control signal, and a plurality of control signals output by each of the two ECUs 120 and 130 are integrated and finally applied to the steering motor 140. have.

The steering motor 140 may be driven by receiving a control signal from the ECU 120 or 130. Specifically, when a command current corresponding to a control signal is input from the ECU 120 or 130, the steering motor 140 may be driven at a rotation speed and torque corresponding to the command current.

The sensor 150 may detect steering information such as a steering angle and torque of a steering wheel and output a detection signal corresponding thereto to the ECUs 120 and 130. The sensor 150 may mean, for example, a steering angle sensor that senses a steering angle of a steering wheel, a torque sensor that senses torque, and the like.

In the present specification, for convenience of explanation, an embodiment is described using two ECUs, but the present disclosure is not limited thereto, and the same may be applied to three or more ECUs.

Meanwhile, the steering assistance system 100 according to the present disclosure may perform fail safe based on a redundant system. For example, the first ECU 120 and the second ECU 130 are connected by a bus to perform internal communication, and information about the state of each of the ECUs 120 and 130 is transmitted through internal communication. According to the start, the steering assistance system 100 performs fail safety based on a redundant system.

Such my communication is, for example, a CAN communication capable of transmitting and receiving messages between the first ECU 120 and the second ECU 130 through a first CAN bus (not shown) and a second CAN bus (not shown). However, it is not limited thereto.

Hereinafter, a method of performing fail safety based on a redundant system and a phenomenon that may occur at this time will be described.

2 is a diagram for explaining a phenomenon that occurs when an ECU fails in the steering assistance system 100 according to the present disclosure.

2, in the steering assistance system 100 according to the present disclosure, a main ECU and a sub ECU exist among two or more ECUs, and the main ECU controls the steering motor 140, but the state of the vehicle , When the main ECU or the like is broken, the main ECU transfers the control right for controlling the steering motor 140 to the sub ECU, so that the steering assistance system 100 may perform fail safety.

For example, when the first ECU 120 is the main ECU and the second ECU 130 is the sub ECU, the first ECU 120 generates a target control signal required for steering of the vehicle and the steering motor 140 Output to, and the second ECU 130 waits. If the first ECU 120 fails, the first ECU 120 transfers the control right to the second ECU 130, and the second ECU 130 to which the control right is transferred generates a target control signal to steer. Output to the motor 140.

At this time, since the steering motor 140 is generally driven at high RPM (Revolutions Per Minute), when the first ECU 120 operating as the main ECU fails, the back electromotive force from the steering motor 140 ; BEMF) occurs instantaneously. When the counter electromotive voltage is generated, the counter electromotive voltage is applied to the second ECU 130, and the second PCO switch 134 included in the second ECU 130 may be burned.

Therefore, it is necessary to prevent ECU damage while implementing fail safety based on a redundancy system.

Hereinafter, a description will be given of a steering assistance system 100 including a circuit for preventing burnout of the ECU due to a counter electromotive voltage of the steering motor 140.

3 is a block diagram schematically showing a first embodiment of a steering assistance system 100 according to the present disclosure, and FIG. 4 is a block diagram schematically showing a second embodiment of the steering assistance system 100 according to the present disclosure. 5 is a block diagram schematically showing a third embodiment of the steering assistance system 100 according to the present disclosure.

The steering assistance system 100 according to the present disclosure may include a first ECU 120, a second ECU 130, a battery 110, a steering motor 140, and an ECU protection module 160.

The first ECU 120 and the second ECU 130 are the same as described above with reference to FIGS. 1 to 2 and thus will be omitted.

The battery 110 may supply power to the first ECU 120, the second ECU 130, and the ECU protection module 160.

The steering motor 140 may be controlled by the first ECU 120 or the second ECU 130. Specifically, it may be controlled by one ECU operating as a main ECU among the first ECU 120 and the second ECU 130. For example, when the first ECU 120 operates as a main ECU, the steering motor 140 is preferentially controlled by the first ECU 120, and the second ECU 130 operates as a main ECU. , The steering motor 140 is preferentially controlled by the second ECU 130.

Since the steering motor 140 is controlled by one ECU operating as a main ECU among the first ECU 120 and the second ECU 130, it may preferably be a single winding motor.

When the control right for controlling the steering motor 140 is transitioned between the first ECU 120 and the second ECU 130, the ECU protection module 160 has a phase voltage of the steering motor 140 equal to or greater than a preset reference voltage. In this case, the supply voltage of the battery 110 may be applied to the PCO switch 124 or 134 included in the ECU 120 or 130 to which the control right is transferred.

For a specific example, when the first ECU 120 operates as a main ECU, if the first ECU 120 fails, the control right of the first ECU 120 is transferred to the second ECU 130, and at this time, steering When a counter electromotive voltage is generated in the motor 140 and the phase voltage of the steering motor 140 becomes higher than the reference voltage, the ECU protection module 160 applies the supply voltage of the battery 110 to the second PCO switch 134. .

When a counter electromotive voltage occurs in the steering motor 140, the supply voltage of the battery 110 is applied to the PCO switches 124 and 134 by the ECU protection module 160, so that the battery 110 and the ECUs 120 and 130 And when the steering motor 140 is electrically connected, the counter electromotive voltage of the steering motor 140 is absorbed by the battery 110 and gradually decreased.

Meanwhile, the ECU protection module 160 may be more than one, and one ECU protection module 160 may be connected to an ECU operating as a sub ECU.

Referring to FIG. 3, for example, when the first ECU 120 is the main ECU and the second ECU 130 is the sub ECU, the ECU protection module 160 is the battery 110 and the second ECU 130 And the steering motor 140 is electrically connected.

As another example with reference to FIG. 4, when the first ECU 120 is a sub ECU and the second ECU 130 is a main ECU, the ECU protection module 160 includes the battery 110 and the first ECU 120 ) And the steering motor 140 are electrically connected.

For another example with reference to FIG. 5, the first ECU protection module 161 is electrically connected to the battery 110, the first ECU 120, and the steering motor 140, and the second ECU protection module 162 ) Is electrically connected to the battery 110, the second ECU 130, and the steering motor 140. At this time, the first ECU protection module 161 is operable when the second ECU 130 fails, and the second ECU protection module 162 is operable when the first ECU 120 fails.

The phase voltage of the steering motor 140 may be a u-phase, v-phase, or w-phase voltage when the steering motor 140 is a three-phase motor. However, it is not limited thereto.

The reference voltage is a reference value for determining whether a counter electromotive voltage has occurred in the steering motor 140, and may be designed in advance to correspond to the internal voltage of the PCO switches 124 and 134. Preferably, the reference voltage may be a break down voltage of a Zener diode included in the ECU protection circuit 200 described later with reference to FIGS. 6 and 8 to 10. However, it is not limited thereto.

Although not shown, the steering assistance system 100 according to the present disclosure illustrated in FIGS. 3 to 5 may include the sensor 150 illustrated in FIG. 1.

Hereinafter, the ECU protection circuit 200 according to the present disclosure will be described in detail.

6 is a block diagram schematically showing the ECU protection circuit 200 according to the present disclosure.

Referring to FIG. 6, the ECU protection circuit 200 according to the present disclosure may include a Zener diode 210, a first switch 220, a second switch 230, and the like.

The Zener diode 210 is a type of diode and can pass current in the forward direction like a general diode. However, unlike a general diode, when a voltage higher than a break down voltage is applied in the reverse direction, current flows in the reverse direction.

For example, when one end of the Zener diode 210 is connected to the steering motor 140 and the phase voltage of the steering motor 140 is equal to or greater than a preset breakdown voltage, a reverse current flows in the reverse direction. That is, the reverse current flows from the steering motor 140 to the Zener diode 210.

The first switch 220 may be turned on when a reverse current is applied from the Zener diode 210. For example, when one end of the first switch 220 is connected to the other end of the Zener diode 200 and a reverse current is applied to one end of the first switch 220, it is turned on, and the first switch 220 is turned on. The first current generated by this flows through the first switch 220.

The second switch 230 may be turned on when the first current generated by the first switch 220 flows. For example, when one end of the second switch 230 is connected to the other end of the first switch 220 and a first current flows and a voltage is applied to one end of the first switch 220, it is turned on.

When the second switch 230 is turned on, a second current generated by the turning on of the second switch 230 flows through the second switch 230. Further, the supply voltage of the battery 110 may be conducted to the PCO switch 320 included in the ECU 300 by turning on the second switch 230.

The PCO switch 320 may be turned on when a supply voltage is applied. When the PCO switch 320 is turned on by the supply voltage, the counter electromotive voltage may be absorbed by the battery 110.

Meanwhile, the PCO switch 320 may be turned on by a control signal of the MCU 310 included in the ECU 300. An operation in which the PCO switch 320 is turned on by the supply voltage of the battery 110 or the control signal of the MCU 310 will be described later with reference to FIG. 11.

As described above, the ECU protection circuit 200 according to the present disclosure provides an effect of protecting the PCO switch 320 by reducing the counter electromotive voltage generated from the steering motor 140.

Hereinafter, the connection relationship between the ECU protection circuit 200, the ECUs 120, 130, and 300, and the steering motor 140 will be described in detail using a circuit diagram, but for convenience, as shown in FIG. 3, the first ECU 120 Will be described based on the steering assistance system 100 and the three-phase steering motor 140 operating as the main ECU.

7 is a circuit diagram showing a connection relationship between the ECUs 120 and 130 and the ECU protection circuit 200 and the steering motor 140 according to the present disclosure.

Referring to FIG. 7, supply voltage switches 121 and 131, inverters 123 and 133, and PCO switches 124 and 134 included in each of the first ECU 120 and the second ECU 130 according to the present disclosure Can all be implemented as FETs. In addition, when the steering motor 140 is a three-phase motor, the inverters 123 and 133 are implemented with six FETs to correspond to each phase of the steering motor 140, and the PCO switches 124 and 134 are three FETs. Can be implemented as

The first MCU (not shown) included in the first ECU 120 may be connected to the gate of the first supply voltage switch 121, the gate of the first inverter 123, and the gate of the first PCO switch 124. .

When the first supply voltage switch 121 is turned on, the supply voltage v _bat of the battery 110 is conducted to the first inverter 123, and the first inverter 123 is the supply voltage of the battery 110 By switching (v _bat ), AC voltage is applied to each of the u-phase 141, v-phase 142, and w-phase 143 of the steering motor 140 according to the timing control of the first MCU.

On the other hand, the second MCU (not shown) of the second ECU 130 according to the present disclosure is also the gate of the second supply voltage switch 131, the gate of the second inverter 133, and the gate of the second PCO switch 134. Can be connected to

At this time, the second supply voltage switch 131 is turned on even when the second ECU 130 is in the standby state so that the counter electromotive voltage of the steering motor 140 is absorbed by the battery 110 connected to the second ECU 130. I can. On the other hand, when the second ECU 130 is in the standby state, the second PCO switch 134 maintains the turn-off state.

The ECU protection circuit 200 may be connected to each of the u-phase 141, v-phase 142, and w-phase 143 of the steering motor 140 and may be connected to each of the gates of the second PCO switch 134.

When the first ECU 120 fails and a counter electromotive voltage occurs in the steering motor 140, the ECU protection circuit 200 applies the supply voltage of the battery 110 to the gate of the second PCO switch 134 2 The second PCO switch 134 may be protected by turning on the PCO switch 134 and absorbing the back electromotive voltage into the battery 110 connected to the second ECU 130.

Hereinafter, the operation of the ECU protection circuit 200 will be described in detail using a specific circuit diagram of the ECU protection circuit 200.

8 is a circuit diagram specifically showing the first embodiment of the ECU protection circuit 200 of FIG. 7.

Referring to FIG. 8, a plurality of Zeno diodes included in the ECU protection circuit 200 may be connected, and the plurality of Zener diodes 210 may be connected for each phase of the steering motor 140.

For a specific example, the steering motor 140 is a three-phase motor, and each of the U-phase 141, V-phase 142, and W-phase 143 of the steering motor 140 is a plurality of Zener diodes 210 It is connected to each end. Further, the other ends of each of the plurality of Zener diodes 210 are all connected to the first switch 220a.

Meanwhile, the first switch 220a and the second switch 230a may be implemented as a Bipolar Junction Transistor (BJT). Preferably, the first switch 220a may be an NPN transistor, and the second switch 230a may be a PNP transistor. However, it is not limited thereto.

As a specific example, when the first switch 220a is an NPN transistor including three terminals, the first terminal of the first switch 220a is connected to the other end of the xenodiode, and the first switch 220a The second terminal of is connected to the second switch 230a, and the third terminal of the first switch 220a is grounded.

In addition, when the second switch 230a is a PNP transistor including three terminals in the same manner as the first switch 220a, the first terminal of the second switch 230a is connected to the first switch 220a. The second terminal of the second switch 230a is connected to the PCO switch 320, and the third terminal of the second switch 230a is connected to the battery 110.

Here, preferably, the first terminal may be a base, the second terminal may be a collector, and the third terminal may be an emitter. However, it is not limited thereto.

When the phase voltage of the steering motor 140 is higher than the breakdown voltage of the Zener diode 210, the reverse current (①) flows from the steering motor 140 to the Zener diode 210, and the reverse current (①) is the first switch. When applied to the first terminal of 220a, a voltage is applied to the first terminal of the first switch 220a, so that the first switch 220a is turned on.

When the first switch 220a is turned on, the first current ② flows from the first terminal of the second switch 230a to the second terminal, and when the first current flows, the second switch ( A voltage is applied to the first terminal of 230a), so that the second switch 230a is turned on.

When the second switch 230a is turned on, the second current (③) flows from the battery 110 to the driver ICs 321, 322, 323 of the PCO switch 320, and the supply voltage of the battery 110 When (v _bat ) is applied to the driver IC 321, 322, 323 of the PCO switch 320 via the second switch 230a, the driver IC 321 of the PCO switch 320, 322 and 323 output a turn-on signal to the PCO switch 320. Then, the PCO switch 320 receiving the turn-on signal is turned on.

On the other hand, since the counter electromotive voltage fluctuates, it may be difficult to stably apply the supply voltage of the battery 110 to the driver ICs 321, 322, and 323 of the PCO switch 320.

Hereinafter, the ECU protection circuit 200 in which the supply voltage of the battery 110 is more stably applied to the PCO switch 320 by modifying the waveform of the supply voltage will be described.

9 is a circuit diagram specifically showing a second embodiment of the ECU protection circuit 200 of FIG. 7, and FIG. 10 is a diagram showing a waveform of a supply voltage applied to the PCO switch 320.

Referring to FIG. 9, as described above with reference to FIG. 8, when a counter electromotive voltage occurs in the steering motor 140, the first switch and the second switch 230a are turned on, and the supply voltage of the battery 110 It is applied to the driver ICs 321, 322, 323 of this PCO switch 320, and the PCO switch 320 is turned on.

Here, the ECU protection circuit 200 may further include a capacitor 250 for modifying the waveform of the supply voltage applied to the PCO switch 320.

In this case, the first terminal of the capacitor 250 may be connected between the second switch 230a and the PCO switch 320, and the second terminal of the capacitor 250 may be grounded.

The capacitor 250 may be plural, and the plurality of capacitors 250 may be connected to each driver IC 321, 322, 323 of the PCO switch 320. For example, when the steering motor 140 is a three-phase motor, each of the three capacitors 250 is between the second switch 230a and the driver ICs 321, 322, 323 of the PCO switch 320 Can be connected to

Here, when the diode 240 is connected between the second switch 230a and the driver ICs 321, 322, 323 of the PCO switch 320, the first terminal of the capacitor 250 is preferably a diode It may be connected between 240 and the driver (Driver) ICs 321, 322, 323 of the PCO switch 320. However, it is not limited thereto.

When the capacitor 250 is connected, the waveform of the supply voltage applied to the PCO switch 320 may be modified by the time constant of the RC circuit. This time constant may be determined by the equivalent resistance of the conducting wire and the capacitance or capacitance of the capacitor 250.

Referring to FIG. 10, for example, the waveform of the supply voltage applied to the PCO switch 320 may include a rising section A1, a sustain section A2, and a falling section A3 of the supply voltage.

In this case, when the time constant is changed by adjusting the capacitance of the capacitor 250, a waveform in which the rising section A1 and the falling section A3 are increased and the sustain section A2 is decreased, or the rising section A1 A waveform in which the over-fall section A3 is reduced and the sustain section A2 is increased may occur. In particular, when the time constant is very small, the waveform of the supply voltage applied to the PCO switch 320 may be a rectangular file.

While the supply voltage applied to the PCO switch 320 is applied, the PCO switch 320 may be turned on.

On the other hand, after the falling period A3, the counter electromotive voltage decreases and the first switch and the second switch are turned off, so that the supply voltage of the battery 110 cannot be applied to the PCO switch 320. In this case, the PCO switch 320 may be turned off during the first period (B) after the falling period (A3).

However, since the control right is transferred immediately after the falling period A3, and the turn-on and turn-off of the PCO switch 320 are controlled by the MCU 310 included in the ECU 300 capable of normal operation, the first period B ) Can be very short time or very close to O.

When the second period C arrives after the first period B, the PCO switch 320 may be turned on and off by the ECU 300 to which the control right is transferred. That is, in the second period (C) in which the control right is shifted, on/off of the PCO switch 320 may be controlled by the MCU 310 operating normally.

As described above, the ECU protection circuit 200 according to the present disclosure provides an effect of more stably preventing a counter electromotive voltage even if a counter electromotive voltage occurs in the steering motor 140.

11 is a circuit diagram specifically showing a third embodiment of the ECU protection circuit 200 of FIG. 7, and FIG. 12 is a first switch 220 and a second switch included in the ECU protection circuit 200 of FIG. 230) It is a diagram showing each example.

Referring to FIG. 11, the first switch 220b and the second switch 230b included in the ECU protection circuit 200 according to the present disclosure are the first switch 220b and the second switch 230b shown in FIG. 8. ) And other transistors.

For example, the first switch 220b and the second switch 230b are Field-Effect Transistors (FETs), preferably the first switch 220b is an NMOS transistor, and the second switch Reference numeral 230b may be a PMOS transistor, but is not limited thereto.

For a specific example, when the first switch 220b is an NMOS transistor including three terminals, the first terminal of the first switch 220b is connected to the other end of the xenodiode, and the first switch 220b The second terminal of is connected to the second switch 230b, and the third terminal of the first switch 220b is grounded.

In addition, when the second switch 230b is a PMOS transistor including three terminals, the first terminal of the second switch 230b is connected to the first switch 220b and the second switch 230b is The second terminal is connected to the PCO switch 320, and the third terminal of the second switch 230b is connected to the battery 110.

Here, preferably, the first terminal may be a gate, the second terminal may be a drain, and the third terminal may be a source. However, it is not limited thereto.

Meanwhile, as shown in FIG. 11, the first switch 220 and the second switch 230 may be implemented as a MOSFET that does not include a bulk terminal. As shown in FIG. 12, the N-channel FET It may be a first switch 220c and a second switch 230c that is a P-channel FET. However, it is not limited thereto.

Meanwhile, the operation method of the ECU protection circuit 200 shown in FIG. 11 is the same as that shown in FIG. 8, and the ECU protection circuit 200 shown in FIG. 11 also uses the capacitor 250 as shown in FIG. It may contain more.

Meanwhile, the above-described ECU protection module 160 and the ECU protection circuit 200 may be implemented as an integrated circuit chip (IC chip) to be included in the above-described ECU 300.

Hereinafter, an ECU 300 including a configuration for performing the functions of the ECU protection module 160 and the ECU protection circuit 200 according to the present disclosure will be described.

13 is a block diagram schematically showing another embodiment of the ECU 300 according to the present disclosure.

Referring to FIG. 13, the ECU 300 according to the present disclosure receives supply power from the battery 110, as described above with reference to FIG. 1, and a steering motor based on steering information input from the sensor 150. You can control 140.

In addition, as described above, the ECU 300 may include an MCU 310, a PCO switch 320, a supply voltage switch 330 and an inverter 240. Here, the supply voltage switch 330 conducts the supply voltage of the battery 110, the inverter 240 outputs a control signal for controlling the operation of the steering motor 140, and the PCO switch 320 transmits the control signal. Conducting or blocking, the MCU 310 may control each of the supply voltage switch 330, the inverter 240, and the PCO switch 320.

However, unlike the first ECU 120 and the second ECU 130 described above with reference to FIGS. 1 to 10, the ECU 300 shown in FIG. 13 is an ECU protection unit (PU, 350). It may contain more.

ECU protection unit 350, similar to the above-described ECU protection module 160 and ECU protection circuit 200, based on the phase voltage of the steering motor 140, whether or not a counter electromotive voltage is generated in the steering motor 140 When it is determined and a counter electromotive voltage occurs in the steering motor 140, the ECU protection unit 350 may conduct the supply voltage of the battery 110 to the PCO switch 320 so that the PCO switch 320 is turned on.

For example, the ECU protection unit 350 compares the phase voltage with a preset reference voltage, and if the phase voltage is greater than the reference voltage, it determines that the counter electromotive voltage has occurred.

Here, the reference voltage may be set based on the breakdown voltage of the PCO switch in the same manner as described above, and may be set equal to the breakdown voltage of the xenodiode 210 included in the ECU protection unit 350. However, it is not limited thereto.

Here, as described above with reference to FIG. 7, the supply voltage switch 330 maintains a turn-on state before the counter electromotive voltage is generated, and the PCO switch 320 maintains a turn-off state before the counter electromotive voltage occurs. And when a counter electromotive voltage is generated, the ECU protection unit 350 may convert it to a turn-on state.

Here, as described above with reference to FIG. 10, the PCO switch 320 maintains the turned-on state for a certain period by the ECU protection unit 350, and is turned on and off by the MCU 310 after a certain period. Can be controlled.

As described above, according to the present disclosure, the present disclosure can provide an ECU protection circuit, an electronic control unit, and a steering assistance system capable of preventing a counter electromotive voltage of a steering motor while implementing fail safety based on a redundant system.

In addition, according to the present disclosure, the present disclosure can provide an ECU protection circuit, an electronic control unit, and a steering assist system capable of protecting the ECU by effectively preventing a counter electromotive voltage of a steering motor using a simple circuit.

In addition, according to the present disclosure, by using a simpler circuit, the present disclosure can provide an ECU protection circuit, an electronic control unit, and a steering assistance system that minimizes the space occupied by elements, contributes to high integration, and minimizes manufacturing costs. have.

In addition, according to the present disclosure, the present disclosure can provide an ECU protection circuit, an electronic control unit, and a steering assist system that provide driving stability by implementing fail safety more stably.

Further, according to the present disclosure, the present disclosure can provide an ECU protection circuit, an electronic control unit, and a steering assistance system capable of efficiently using a battery by applying a circuit optimized for a dark current of a battery.

The description above and the accompanying drawings are merely illustrative of the technical idea of the present disclosure, and those of ordinary skill in the technical field to which the present disclosure pertains, combinations of configurations without departing from the essential characteristics of the present disclosure Various modifications and variations, such as separation, substitution, and alteration, will be possible. Accordingly, the embodiments disclosed in the present disclosure are not intended to limit the technical idea of the present disclosure, but to describe, and the scope of the technical idea of the present disclosure is not limited by these embodiments. That is, as long as it is within the scope of the problem solving of the present disclosure, one or more of the components may be selectively combined and operated. The scope of protection of the present disclosure should be interpreted by the claims below, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present disclosure.

100: steering assistance system 110: battery
120: first electronic control unit 130: second electronic control unit
140: steering motor 150: sensor
160: ECU protection module 200: ECU protection circuit
210: Zeno diode 220: first switch
230: second switch 300: electronic control unit
310: MCU 320: PCO switch
330: supply voltage switch 340: inverter
350: ECU protection

Claims (22)

In the ECU (Electronic Controller Unit) protection circuit,
A Zener diode having one end connected to the steering motor and allowing a reverse current to flow when the phase voltage of the steering motor is equal to or higher than a preset break down voltage;
A first switch having one end connected to the other end of the Zener diode and turned on when the reverse current is applied to allow a first current to flow; And
A second switch having one end connected to the other end of the first switch, and turning on when the first current flows, so that the second current flows and the supply voltage of the battery is conducted to the PCO (Phase Cut Off) switch,
The reverse current flows from the steering motor to the Zener diode,
The first current flows from one end of the second switch to the other end of the first switch,
The PCO switch, ECU protection circuit, characterized in that turned on when the supply voltage is applied. The method of claim 1,
The breakdown voltage, ECU protection circuit, characterized in that corresponding to the breakdown voltage of the PCO switch. The method of claim 1,
The Zener diode is plural,
ECU protection circuit, characterized in that the plurality of Zener diodes are connected for each phase of the steering motor. The method of claim 3,
The steering motor is a three-phase motor,
Each of the U-phase, V-phase, and W-phase of the steering motor is connected to one end of each of the plurality of Zener diodes. The method of claim 1,
The first switch is a transistor including three terminals,
The first terminal of the first switch is connected to the other end of the Zeno diode,
The second terminal of the first switch is connected to one end of the second switch,
ECU protection circuit, characterized in that the third terminal of the first switch is grounded. The method of claim 1,
The second switch is a transistor including three terminals,
The first terminal of the second switch is connected to the other end of the first switch,
The second terminal of the second switch is connected to one end of the PCO switch,
ECU protection circuit, characterized in that the third terminal of the second switch is connected to the battery. The method of claim 1,
The first switch and the second switch is an ECU protection circuit, characterized in that the junction transistor (Bipolar Junction Transistor, BJT). The method of claim 7,
The first switch is an NPN transistor,
The second switch is an ECU protection circuit, characterized in that the PNP transistor. The method of claim 1,
The first switch and the second switch, the ECU protection circuit, characterized in that the field effect transistor (Field-Effect Transistor, FET). The method of claim 9,
The first switch is an NMOS transistor,
The second switch is an ECU protection circuit, characterized in that the PMOS transistor. The method of claim 1,
The ECU protection circuit further comprises a capacitor for modifying the waveform of the supply voltage applied to the PCO switch,
The first terminal of the capacitor is connected between the second switch and the PCO switch,
ECU protection circuit, characterized in that the second terminal of the capacitor is grounded. The method of claim 11,
The waveform of the supply voltage includes a rising section, a sustain section, and a falling section of the supply voltage,
The PCO switch, ECU protection circuit, characterized in that turned off after the falling period. A supply voltage switch to conduct a supply voltage of the battery;
An inverter outputting a control signal for controlling the operation of the steering motor;
A PCO (Phase Cut Off) switch to conduct the control signal to the steering motor or to cut off the supply of the control signal;
A microcontroller unit (MCU) controlling each of the supply voltage switch, the inverter, and the PCO switch; And
Determines whether a counter electromotive voltage occurs in the steering motor based on the phase voltage of the steering motor, and when a counter electromotive voltage occurs in the steering motor, conducts the supply voltage to the PCO switch so that the PCO switch is turned on. Electronic control unit with ECU protection. The method of claim 13,
The supply voltage switch maintains a turned-on state from before the counter electromotive voltage is generated,
The PCO switch is an electronic control unit, characterized in that the turn-off state is maintained before the back electromotive voltage is generated, and when the back electromotive voltage is generated, the electronic control unit is switched to the turned-on state by the ECU protection unit. The method of claim 14,
The PCO switch is an electronic control unit, characterized in that the turn-on state is maintained for a predetermined period by the ECU protection unit, and the on-off is controlled by the MCU after the predetermined period. The method of claim 13,
The ECU protection unit compares the phase voltage with a preset reference voltage, and determines that the counter electromotive voltage has occurred when the phase voltage is greater than the reference voltage. The method of claim 16,
The reference voltage is set based on the withstand voltage of the PCO switch. A first electronic control unit including a first MCU, a first inverter and a first PCO switch;
A second electronic control unit including a second MCU, a second inverter and a second PCO switch;
A battery supplying power to the first electronic control unit and the second electronic control unit;
A single winding steering motor controlled by the first electronic control unit or the second electronic control unit;
When the control right for controlling the steering motor is transitioned between the first electronic control unit and the second electronic control unit, if the phase voltage of the steering motor is equal to or higher than a preset reference voltage, the supply voltage of the battery is adjusted to the control right. Steering assistance system including an ECU protection module applied to the PCO switch included in the shifted electronic control unit. The method of claim 18,
The reference voltage is a breakdown voltage of a Zener diode included in the ECU protection module. The method of claim 18,
The reference voltage is set based on the internal pressure of the PCO switch included in the electronic control unit to which the control right is shifted. The method of claim 18,
The ECU protection module transforms the waveform of the supply voltage and applies it to the PCO switch,
The PCO switch, steering assistance system, characterized in that turned on while the supply voltage is applied. The method of claim 21,
The waveform of the supply voltage includes a rising section, a sustain section, and a falling section of the supply voltage,
The PCO switch, the steering assistance system, characterized in that the on-off is controlled by the electronic control unit to which the control right is transferred after the descending section.

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