JP2012201329A - Electronic control unit for vehicle and electronic control system for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic control unit (ECU) for a vehicle capable of backing up a control power supply or a sensor power supply in the ECU even when a ground fault, power failure or the like occurs, and also capable of suppressing an increase in manufacturing cost.SOLUTION: The ECU 100 includes: a microcomputer 11 for controlling the ECU as a whole; an ECU control power supply 13 for supplying the microcomputer 11 with electric power; a sensor power supply 14 for supplying an externally placed temperature sensor 163 with electric power; and a conducting element 18 connected to an output side of the ECU control power supply 13 and an output side of the sensor power supply 14. When an open failure of the ECU control power supply 13 occurs, the resistance of the ECU control power supply 13 is increased, and the conducting element 18 gets into a short circuit state through occurrence of a potential difference between both sides of the conducting element 18. Thereby, the output side of the sensor power supply 14 is electrically connected to the output side of the ECU control power supply 13, and electrically connected to a power-supply voltage input port in the microcomputer 11.

Description

  The present invention relates to a vehicular electronic control device and a vehicular electronic control system, and more particularly to a vehicular control device and a vehicular electronic control system having a built-in backup structure of a plurality of power supplies.

  In general, vehicles such as automobiles are equipped with a plurality of electronic control devices called ECUs (Electrical Control Units) that electrically control various devices and devices such as engines, wipers, power windows, and lights. Some ECUs having a sensor function for detecting outside air temperature and the like include an ECU control power source and a sensor power source.

  FIG. 5 is a block diagram schematically showing a configuration of a general ECU.

  In FIG. 5, an ECU 50 is connected to an external battery 61 via a microcomputer 51 that generally controls the ECU, a diode 52, and supplies power to the microcomputer 51. A sensor power supply 54 that is connected to the battery 61 and supplies power to the temperature sensor 63 that is a power supply target; a CAN communication circuit 55 that is connected to the microcomputer 51 and connected to other ECUs so as to be able to transmit and receive; Drive elements 56 and 57 for driving the motor 64 and the lamp 65 by the output from the microcomputer 51 are provided. In addition to the wiper switch 62, the microcomputer 51 is connected with various switches such as a power window switch and a tail lamp switch.

  Here, since the sensor power supply 54 outputs to the temperature sensor 63 provided outside the ECU 50, there is a possibility of a ground fault (GND short-circuit) at the output end. For example, if the ECU control power source and the sensor power source are configured by a single supply unit, when the output end of the sensor power source is grounded, the ECU control power source is also grounded, and as a result, the entire ECU 50 operates. It becomes impossible. According to this configuration, since the ECU control power supply 53 and the sensor power supply 54 are configured separately, even if the sensor power supply 54 is grounded, the ECU control power supply 53 is not grounded. Can be prevented from becoming inoperable.

  Further, in the configuration of FIG. 5, since a plurality of ECU control power sources and sensor power sources are provided, if any of these power sources fails, power is promptly supplied from another supply unit. There is a demand to configure as follows. In order to meet this demand, for example, as shown in FIG. 6, a configuration may be considered in which a connection portion 58 that electrically connects the output side of the ECU control power supply 53 and the output side of the sensor power supply 54 is provided in the ECU 60. However, in the case of this configuration, if any one power source has a ground fault, the entire ECU 60 becomes inoperable. Therefore, it is not meaningful to separately configure the ECU control power source 53 and the sensor power source 54. The initial problem cannot be achieved.

FIG. 7 is a block diagram schematically showing a control structure in a conventional power supply system.
A power supply system 70 of FIG. 7 includes a DC power supply 71, a load 72, and system relays SR1 and SR2 as switches connected between the DC power supply 71 and the load 72. In the system relay off control at the time of ignition off, even if the communication between the ECUs is stopped when the operation of the load 72 is stopped and the stop condition of the system relays SR1 and SR2 is satisfied, the load 74 can be operated by the ECU 75. It is possible. That is, the output gradual reduction process of the load 74, which is the second load, can be executed without performing bidirectional communication between the ECUs after the operation of the load 72, which is the first load, is stopped. In particular, when the load 74 is a power steering device, it is possible to prevent a rapid decrease in the steering assist force.

JP 2007-176393 A

  However, in the power supply system of FIG. 7, after the operation of the first load is stopped, power is supplied only during the operation required time of the second load without performing bidirectional communication between the plurality of ECUs. That is, in the configuration of FIG. 7, when one of the plurality of ECUs fails, power cannot be supplied from another ECU, and the control power source or sensor power source in the ECU may become inoperable. There is.

  An object of the present invention is to provide an electronic control for a vehicle that can back up a control power source or a sensor power source in an ECU even when a ground fault or a power source failure occurs, and can suppress an increase in manufacturing cost. An apparatus and an electronic control system for a vehicle are provided.

  In order to solve the above problems, a vehicle electronic control device according to the present invention is a vehicle electronic control device having a power backup structure, and a control unit that comprehensively controls the vehicle electronic control device; A control power source that supplies power to the control unit, a detection unit power source that supplies power to a detection unit provided outside, and an output side of the control power source and an output side of the detection unit power source are connected A conduction element, and when the power supply from one of the control power supply and the detection unit power supply is stopped, the conduction element changes from an insulated state to an electrically connected state, and the other power supply Electric power is supplied to the output side of the one power source through the conductive element.

  The vehicular electronic control device further includes a rectifying element connected between the control power source and the conduction element so that the control power source side is a cathode side, and supplies power from the control power source. Only when the power supply is stopped, power is supplied from the detection unit power source to the output side of the control power source via the conduction element and the rectifying element.

  Further, when one of the control power source and the detection unit power source fails, power is supplied from the other power source to the output side of the one power source via the conductive element.

  Further, only when the control power supply fails, power is supplied from the detection unit power supply to the output side of the control power supply through the conduction element and the rectifying element.

  The vehicle electronic control system according to the present invention is an electronic control system including a plurality of electronic control devices, wherein a power source and one electronic control device group of the plurality of electronic control devices are connected to a first fuse element. A first circuit connected via a first fuse, and a second circuit connecting the power supply and another electronic control device group via a second fuse element, wherein the one electronic control device group comprises the first circuit As well as at least one electronic control unit connected to the second circuit, the at least one electronic control unit being connected to the second circuit via a conduction element and provided in the first circuit. When the first fuse element is cut, electric power is supplied to the at least one electronic control device via the second circuit and the conduction element.

  According to the vehicle electronic control device according to the present invention, when the power supply from either the control power source or the detection unit power source is stopped, the conductive element is changed from the insulated state to the electrically connected state, Since power is supplied from the other power source to the output side of one power source through a conducting element, the control power source or sensor power source can be backed up even if a ground fault or power source failure occurs. Further, since the conductive element is provided between the output side of the control power source and the output side of the detection unit power source, an increase in manufacturing cost can be suppressed. Further, since the control power supply and the detection unit power supply are provided separately, even if the detection unit power supply is grounded, the control power supply is not grounded, and the entire electronic control device becomes inoperable. Can be avoided.

  In addition, a rectifying element connected so that the control power supply side becomes the cathode side is provided between the control power supply and the conduction element, and only when the power supply from the control power supply is stopped, Power is supplied from the power supply to the output side of the control power supply through the conduction element and the rectifying element. Therefore, the control power supply can be backed up reliably.

  According to the vehicle electronic control system of the present invention, one electronic control device group includes at least one electronic control device connected to the second circuit as well as the first circuit, One electronic control unit is connected to the second circuit via the conducting element. And when the 1st fuse element provided in the 1st circuit is cut, electric power is supplied to at least one electronic control unit via the 2nd circuit and a conduction element. That is, during normal times, power is not supplied to the at least one electronic control unit via the second path, and power is supplied via the second path when the first fuse element is disconnected. Therefore, the second path can be made to function as a backup circuit for the first path, the capacity of the second fuse element can be reduced, and by reducing the diameter of the electric wire, the weight of the vehicle can be reduced. Fuel consumption can be improved.

It is a figure showing roughly the composition of the electronic controller for vehicles concerning a 1st embodiment of the present invention. It is a figure which shows typically the structure of the conventional vehicle power supply system for supplying electric power to several power supply control apparatuses (ECU). It is a figure which shows typically the structure of the power supply system for vehicles which concerns on 2nd Embodiment of this invention. It is a figure which shows the modification of a structure of ECU in FIG. 1 is a block diagram schematically showing a configuration of a general ECU. It is a block diagram which shows schematically the other structure of general ECU. It is a block diagram which shows roughly the control structure in the conventional power supply system.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram schematically showing the configuration of the vehicle electronic control device according to the first embodiment of the present invention.
1, a vehicle electronic control device (hereinafter referred to as ECU) 100 is one of control devices mounted together with ECUs 200, 300,... In a vehicle such as an automobile, and is a wiper provided in the vehicle. Control various devices such as power windows and lamps. The ECUs 200, 300,... Connected to the ECU 100 execute various functions such as ABS, EFI, ECS, and other functions of the vehicle.

  The ECU 100 is connected to an external battery 161 via a diode 12 that controls the ECU as a whole, an ECU 12 that supplies electric power to the microcomputer 11, and a diode 12. Connected to the battery 161 and connected to the temperature sensor 163 (detection unit) provided externally to supply power to the sensor 14 (detection unit power supply) and to the microcomputer 11 so as to be able to transmit and receive to other ECUs. The CAN communication circuit 15 and drive elements 16 and 17 for driving the motor 164 and the lamp 165 by the output from the microcomputer 11, respectively. In addition to the wiper switch 162 provided outside, the microcomputer 11 is connected to various switches such as a power window switch and a tail lamp switch. In this embodiment, the output voltages of the ECU control power supply 13 and the sensor power supply 14 are both 5V.

  In the ECU 100, by providing the ECU control power source 13 and the sensor power source 14, the power source that supplies power to the microcomputer 11 and the power source that supplies power to the outside are separated. Therefore, even when the output terminal of the sensor power supply 14 is grounded, it is possible to prevent a ground fault of the ECU control power supply 13 and prevent the entire ECU 100 from becoming inoperable. Although not shown in FIG. 1, a plurality of ECU control power sources 13 and a plurality of sensor power sources 14 are also provided in the ECU 100. However, it is sufficient that at least one ECU control power source 13 is provided, and at least one sensor power source 14 is also provided.

  In the present embodiment, a conduction element 18 connected to the output side of the ECU control power supply 13 and the output side of the sensor power supply 14 is provided. The conductive element is normally in an insulated state, and is configured to shift from a high resistance state to a low resistance state when a predetermined potential difference is generated at both ends thereof so that a current flows inside. In the ECU 100, when a potential difference of a predetermined value or more is generated at both ends of the conduction element 18, the conduction element 18 is short-circuited, and the output side of the ECU control power supply 13 and the output side of the sensor power supply 14 are electrically connected. The conductive element 18 is advantageous in that it does not require a complicated circuit and can be easily attached as a passive element.

  In the ECU 100 configured as described above, when the ECU control power supply 13 is opened due to disconnection or the like, the resistance of the ECU control power supply 13 increases, a potential difference is generated between both ends of the conduction element 18, and the conduction element 18 is short-circuited. It becomes a state. As a result, the output side of the sensor power supply 14 is electrically connected to the output side of the ECU control power supply 13 and is electrically connected to the power supply voltage input port (VDD) in the microcomputer 11. Therefore, the sensor power supply 14 functions as a backup power supply for the ECU control power supply 13, and power is supplied from the sensor power supply 14 to the microcomputer 11.

  On the other hand, when the sensor power supply 14 is broken due to disconnection or the like, the resistance of the sensor power supply 14 increases, a potential difference is generated between both ends of the conductive element 18, and the conductive element 18 is short-circuited. As a result, the output side of the ECU control power supply 13 is electrically connected to the output side of the sensor power supply 14 and is electrically connected to the power supply voltage input port (AD_ref) in the microcomputer 11. Therefore, in this case, the ECU control power supply 13 functions as a backup power supply for the sensor power supply 14, and power is supplied from the ECU control power supply 13 to the microcomputer 11.

  That is, by connecting the output terminals of both the ECU control power supply 13 and the sensor power supply 14 via the conduction element 18, when one of the two power supplies fails, the power supply of one power supply from the other power supply It is possible to supply power to the output side, realizing bidirectional power supply backup.

  According to the present embodiment, when the power supply from any one of the ECU control power source 13 and the sensor power source 14 is stopped, the conduction element 18 changes from the insulated state to the electrically connected state, and the other power source. Since electric power is supplied from the power source to the output side of one power source through the conduction element 18, the ECU control power source 13 or the sensor power source 14 can be backed up even if a ground fault or a power source failure occurs. Further, since the conductive element 18 is provided between the output side of the ECU control power supply 13 and the output side of the sensor power supply 14, an increase in manufacturing cost can be suppressed. Further, since the ECU control power supply 13 and the sensor power supply 14 are provided separately, even if the sensor power supply 14 is grounded, the ECU control power supply 13 is not grounded, and the entire ECU 100 becomes inoperable. Can be avoided.

  Next, the configuration in which the conduction element is built in the predetermined ECU not only prevents the operation of each power source of the ECU control power source 13 and the sensor power source 14, but also the battery 161 and the plurality of ECUs 100, 200, 300,.・ ・ It is possible to improve the power supply circuit configuration for connecting and as follows.

FIG. 2 is a diagram schematically showing a configuration of a conventional vehicle power supply system for supplying electric power to a plurality of ECUs.
In FIG. 2, for example, four ECUs (A) to ECU (D) (one electronic control device group) are connected to a fuse A, and the fuse A is connected to a power source via a fuse C. Further, ECU (C) to ECU (F) (another electronic control device group) are connected to a fuse B, and the fuse B is connected to a power source via the fuse C. Of ECU (A) to ECU (D), ECU (C) and ECU (D) are positioned as important ECUs, and are connected to a line where fuse A is interposed and a line where fuse B is interposed, respectively. Yes. That is, electric power is supplied to ECU (C) and ECU (D) through two lines provided with fuse A and fuse B, respectively. Therefore, when one of the fuse A and the fuse B is blown, electric power is supplied to the ECU (C) and the ECU (D) from the line where the other fuse is provided.

In the power supply circuit configuration configured as described above, when the rated current of each ECU is 2 A (ampere), for example, the capacity of the fuse A is calculated as follows.
・ 2.0 [A / piece] × 4 [piece] = 8.0 [A]
・ 8.0 [A] /0.5=16 [A] <20 [A] (0.5 is a safety factor)
∴ (capacity of fuse A) = 20 [A]
Further, the capacity of the fuse B is calculated as (the capacity of the fuse B) = 20 [A] in the same manner as the fuse A. Therefore, in the conventional power circuit configuration, it is necessary to select a fuse having a capacity of 20 amperes for both the fuse A and the fuse B.

FIG. 3 is a diagram schematically showing the configuration of the vehicle power supply system according to the second embodiment of the present invention.
In FIG. 3, ECU (C) and ECU (D) are positioned as important ECUs, and a line (first circuit) and a fuse B (second fuse element) in which a fuse A (first fuse element) is interposed, respectively. 2 is the same as that of the power supply circuit configuration of FIG. The ECU (C) and ECU (D) (at least one electronic control unit) in FIG. The line provided with the fuse B is connected to the ECU (C) and the ECU (D) through a conduction element.

  In this power circuit configuration, electric power is supplied to the ECUs (A) to (D) in the line where the fuse A is provided. In addition, in the line where the fuse B is provided, the ECU (C) and the ECU (D) are each provided with a conduction element, and therefore the ECU (C) and the ECU (D) are usually not supplied with electric power. However, electric power is supplied only to the ECU (E) and the ECU (F). When the fuse A is cut by melting or the like, the conduction elements of the ECU (C) and ECU (D) are short-circuited, and the ECU (E) and ECU (F (F) are connected in the line where the fuse B is provided. ) As well as ECU (C) and ECU (D).

Therefore, by installing a conduction element in an important ECU that always wants to secure power supply and connecting it to another power supply line via the conduction element, another power supply line different from the normal power supply line can be connected. It can function as a backup line. As a result, it is possible to reduce the cable diameter and the fuse capacity in the backup line. Specifically, the capacity of the fuse B can be calculated as follows in the power supply circuit configuration of FIG.
・ 2.0 [A / piece] × 2 [piece] = 4.0 [A]
・ 4.0 [A] /0.5=8.0 [A] <10 [A] (where 0.5 is a safety factor)
∴ (capacity of fuse B) = 10 [A]
Note that the capacity of the fuse A is the same as that of the fuse A of FIG. 2, and (capacity of the fuse A) = 20 [A] is calculated.

  Therefore, in the vehicle power supply system according to the present embodiment, the capacity of the fuse B can be reduced from 20A to 10A by about 50% as compared with the conventional vehicle power supply system of FIG. Further, as the capacity of the fuse B decreases, the diameter of the cable (portion “A” in FIG. 2) from the output end of the fuse B to the branch point from the ECU (C) to the ECU (F) is realized. Is also possible. Further, by reducing the diameter of the electric wire, it is possible to reduce the weight of the vehicle and improve the fuel consumption.

  In addition, since the fuse B having a smaller capacity than the necessary capacity is selected, it cannot be said that the fuse B has a sufficient capacity when the fuse A is melted. It is possible to protect the cable from C) to ECU (F) up to the branch point. Further, the ECU 100 may be provided with a notification means for notifying a failure by a lamp, sound, character display, or the like. According to this configuration, when the fuse A is blown, it is possible to promptly notify the user that the fuse A has been blown and prevent the user from continuing to use the ECU when the fuse A is blown. It becomes possible to do.

  FIG. 4 is a diagram showing a modification of the configuration of the ECU 100 in FIG. The configuration of the ECU shown in FIG. 4 is basically the same as the configuration of the ECU 100 shown in FIG. 1, and corresponding elements are denoted by the same reference numerals and description thereof is omitted.

  In FIG. 4, the ECU 110 includes a diode (rectifying element) 19 connected between the ECU control power supply 13 and the conduction element 18 so that the ECU control power supply 13 side is the cathode side and the conduction element 18 side is the anode side. In addition.

  In the configuration of the ECU 110, when the ECU control power supply 13 fails, electric power is supplied from the sensor power supply 14 to the output side of the ECU control power supply 13 through the conduction element 18 and the diode 19. That is, the conductive element 18 is short-circuited by the rectifying action of the diode 19 only when the ECU control power source 13 side, which is the cathode side, of the diode 19 is lower than the anode side. As a result, the output side of the sensor power supply 14 is electrically connected to the output side of the ECU control power supply 13 and is electrically connected to the power supply voltage input port (VDD) in the microcomputer 11.

  According to this modification, the diode 19 connected so that the ECU control power supply 13 side becomes the cathode side is provided between the ECU control power supply 13 and the conduction element 18, and the ECU control power supply 13 has failed. Only sometimes, power is supplied from the sensor power supply 14 to the output side of the ECU control power supply 13 via the conducting element 18 and the diode 19. Therefore, the ECU control power source 13 can be reliably backed up.

  In the above-described embodiment, the ECU 100 supplies power from the other power source to one power source when one of the ECU control power source 13 and the sensor power source 14 fails, but the present invention is not limited to this. Absent. When power supply from any one of the ECU control power supply 13 and the sensor power supply 14 is stopped, power may be supplied from the other power supply to one power supply.

  In the above embodiment, the ECU 110 supplies power from the sensor power supply 14 to the output side of the ECU control power supply 13 via the conduction element 18 and the diode 19 only when the ECU control power supply 13 fails. However, it is not limited to this. Only when power supply from the ECU control power supply 13 is stopped, power may be supplied from the sensor power supply 14 to the output side of the ECU control power supply 13 via the conduction element 18 and the diode 19.

  In the above embodiment, the sensor power supply 14 is connected to the temperature sensor 163, but the present invention is not limited to this, and is not limited to this. The remaining amount sensor of the fuel, the mirror angle sensor, the seat position sensor, the tilt and telescopic adjustment sensor, It may be connected to a sensor (for auto light), an intermittent wiper time setting volume SW (steering SW), and the like.

  Further, in the above embodiment, the diode 19 is provided between the ECU control power supply 13 and the conduction element 18, but the present invention is not limited to this, and any rectification element that provides a rectification action for flowing a current only in one direction. It may be a configuration.

  Moreover, in the said embodiment, although the power supply 14 for sensors supplies electric power to the temperature sensor 163 provided outside, it is not restricted to this. Another detection unit serving as a power supply target may be provided, and the sensor power supply 14 may supply power to the other detection unit.

  Moreover, this embodiment shows an example of the vehicle electronic control device according to the present invention, and is not limited to this. The detailed configuration of the vehicle electronic control device according to the present embodiment can be changed as appropriate without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 11 Microcomputer 12 Diode 13 ECU power supply 14 Sensor power supply 15 CAN communication circuit 16, 17 Drive element 18 Conductive element 19 Diode 100, 200, 300 ECU
161 Battery 162 Wiper 163 Temperature sensor 164 Motor 165 Lamp

Claims (5)

An electronic control device for a vehicle having a power backup structure,
A control unit that comprehensively controls the vehicle electronic control device;
A control power supply for supplying power to the control unit;
A power source for a detection unit that supplies power to a detection unit provided outside;
A conduction element connecting the output side of the control power supply and the output side of the detection unit power supply,
When power supply from any one of the control power source and the detection unit power source is stopped, the conductive element is changed from an insulating state to an electrically connected state, and the other power source is connected via the conductive element. An electronic control device for a vehicle, wherein electric power is supplied to an output side of the one power source. A rectifying element connected between the control power supply and the conduction element so that the control power supply side is a cathode side;
Only when power supply from the control power supply is stopped, power is supplied from the detection unit power supply to the output side of the control power supply through the conduction element and the rectifying element. The vehicle electronic control device according to claim 1.   When one of the control power supply and the detection unit power supply fails, power is supplied from the other power supply to the output side of the one power supply through the conduction element. The vehicle electronic control device according to claim 1.   The electric power is supplied from the detection unit power source to the output side of the control power source via the conduction element and the rectifying element only when the control power source fails. Electronic control device for vehicles. A power supply system for a vehicle comprising a plurality of electronic control devices,
A first circuit that connects a power source and one electronic control device group of the plurality of electronic control devices via a first fuse element;
A second circuit for connecting the power source and another electronic control unit group via a second fuse element;
The one electronic control device group includes at least one electronic control device connected to the second circuit as well as the first circuit,
The at least one electronic control unit is connected to the second circuit via a conductive element;
When the first fuse element provided in the first circuit is cut, electric power is supplied to the at least one electronic control unit via the second circuit and the conduction element. Power system.

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