JP2006273046A - Power supply control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply control system capable of suppressing lowering of a voltage in a supply circuit in a system for switching a plurality of batteries. <P>SOLUTION: This power supply control system includes: an electric actuation device driven by electric power supplied from a first power supply or a second power supply; a first power supply circuit and a second power supply circuit for supplying the electric power from the first power supply and the second power supply to the electric actuation device; a first power supply switching device and a second power supply switching device for switching the first power supply circuit and the second power supply circuit between conduction and non-conduction; a normal-time switching controller for conducting the first power supply circuit and cutting off the second power supply circuit when the first power source is normal; an abnormal-time switching device for cutting off the first supply circuit and conducting the second power supply circuit when the first power supply is abnormal; a first power supply reverse-flow preventing device and a second power supply reverse-flow preventing device for preventing reverse-flow of the currents of the first power supply circuit and the second power supply circuit; a short-circuit device for short-circuiting the first power supply reverse-flow preventing device and the second power supply reverse-flow preventing device after the electric actuation device is started. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a power supply control system that includes a plurality of power supplies, and controls to supply power from the other power supply when an abnormality occurs in one power supply.

This type of technology includes a plurality of power supplies, and if an abnormality occurs in the main power supply device or the main current supply line that supplies current from the main power supply device to the control device, an auxiliary battery is connected to the control device to A device that supplies current to a control device from a battery is disclosed (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 2001-114039

  However, in the above prior art, the control device has a plurality of current supply lines connected to the main power supply and the auxiliary battery, but each current supply line is provided with a diode before input to the control device. Causes a voltage drop. For example, if the voltage drops as during cranking, the voltage drop due to cranking and the voltage drop due to the diode cannot supply sufficient voltage to the control device, making the control device inoperable. There was a problem that there is a risk of becoming.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a power supply control system that suppresses a decrease in voltage in a power supply circuit in a system that switches a plurality of batteries. .

  To achieve the above object, according to the present invention, a first power source, a second power source, an electric actuator driven by electric power supplied from the first power source or the second power source, and electric power from the first power source to the electric actuator. In a power supply control system comprising a first power supply circuit for supplying power and a second power supply circuit for supplying power from the second power supply to the electric actuator, first power supply switching means for switching between energization and interruption of the first power supply circuit And a second power supply switching means for switching between energization and shutoff of the second power supply circuit, and a normal time switching control means for energizing the first power supply circuit and shutting off the second power supply circuit when the first power supply is normal. When the first power supply is abnormal, the first power supply circuit is shut off and the second power supply circuit is energized. The first power supply backflow prevention means for preventing the backflow of the current of the first power supply circuit; Second power supply reverse that prevents reverse current flow of the second power supply circuit And prevention means, after the electric actuator boot, comprising a short-circuiting means for short-circuiting the first power backflow prevention means and the second power supply backflow prevention means.

  In the power supply control system of the present invention, current can be supplied while suppressing voltage drop from the power supply.

  The best mode for realizing the power supply control system of the present invention will be described below with reference to the drawings.

  First, the configuration will be described.

  FIG. 1 is a system diagram illustrating an overall configuration of a brake system to which the power supply control system according to the first embodiment is applied.

  The brake system in the present embodiment controls the brake main control device 2 that controls the braking force of the front and rear wheels based on information from each sensor and the like, and controls the front wheel hydraulic brake unit 3 based on the command value of the brake main control device 2. A front wheel hydraulic brake control device 1 is provided.

  The front wheel hydraulic brake control device 1 is a hydraulic brake that controls the operation of the left and right front wheel hydraulic brakes B1 and B2 via the front wheel hydraulic brake unit 3 based on a braking command signal from the brake main control device 2. It is a by-wire control means.

  The front wheel hydraulic brake unit 3 includes a brake hydraulic pump provided separately from the master cylinder in the unit and a motor for driving the pump. The front wheel hydraulic brake unit 3 responds to a control command from the front wheel hydraulic brake control device 1. Supply hydraulic pressure to brakes B1 and B2.

  The front wheel hydraulic brake control device 1 is configured to be capable of feedback control by a hydraulic pressure monitor using the wheel hydraulic pressure sensors WP1 and WP2.

  The front wheel hydraulic brake unit 3 and the brake pedal BP are connected by a hydraulic circuit so that a fail-safe valve (not shown) is released at the time of failure so that the pedaling force applied to the brake pedal BP is transmitted to the front wheel hydraulic brakes B1 and B2. It is composed.

  The front wheel hydraulic brake control device 1 includes a microcomputer 16 (see FIG. 2), and the microcomputer 16 is supplied with electric power from a first power supply PWR1 and a second power supply PWR2. The microcomputer 16 is activated by a first ignition switch signal or a second ignition switch signal for starting the engine by the first power supply PWR1 or the second power supply PWR2, or a wakeup switch signal such as a brake lamp switch.

  On the other hand, the left and right rear wheel electric brake units 4 and 5 are electric brake actuators and have a control communication line common to the rear wheels. Further, the motor and the like in the unit can be controlled based on the braking command from the brake main control device 2.

  This electric brake applies a braking force to the rear wheel based on the pedal operation information of the driver, and generates a braking force by pressing a brake pad against a brake disk by a motor or the like, for example. Further, when a regenerative brake control device 7 to be described later is operated, the left and right rear wheel electric brakes are obtained by subtracting the braking force generated by the regenerative brake control device 7 from the required braking force of the rear wheels. Generated by B3 and B4.

  Note that the rear wheel side that employs an electric brake does not generate braking force when the system is shut down during a failure. Also, the rear wheel electric brake unit 4 is supplied with power only from the first power supply PWR1, and the rear wheel electric brake unit 5 is supplied with power only from the second power supply PWR2, and is supplied like the front wheel hydraulic brake control device 1. The source is not a double system. However, the rear wheel has a smaller braking force than the front wheel (generally, the braking force ratio between the front wheel and the rear wheel is about 7: 3). For example, even if the brake-by-wire control fails, the braking force is sufficient only with the front wheel. Can be secured.

  On the rear wheel side, in addition to the rear wheel electric brake units 4 and 5, a brake generator BG that generates a braking force by generating electric power by the rotational force of the wheel, and a regenerative brake control device 7 that controls the operation of the brake generator BG. Is provided. The regenerative brake control device 7 monitors the SOC (State Of Charge) of a battery that can be stored outside the figure, and transmits the SOC to the brake main control device 2. Further, the regenerative brake control device 7 controls the operation of the brake generator BG based on a command signal from the brake main control device 2.

  Each front and rear wheel is provided with wheel speed sensors V1S, V2S, V3S, and V4S for detecting the wheel speed. These wheel speed sensor values V1, V2, V3, and V4 are transmitted to the brake main control device 2.

  The brake pedal BP is provided with sensors SEN1, SEN2, and SEN3 for detecting three brake pedal operation information. That is, as a performance unique to brake-by-wire, sensors for detecting three brake pedal operation information are provided so that accurate measurement (that is, detection of the driver's operation intention) can be performed even if one sensor fails. ing.

  The brake main control device 2 calculates front and rear wheel braking forces and transmits a control command to each device. The brake main control device 2 is input with brake pedal operation signals S1, S2, S3, and other control devices 6 such as a first ignition switch signal, a second ignition switch signal, a wake-up switch signal, and an engine control device. . Further, like the front wheel hydraulic brake control device 1, a microcomputer is provided inside, and power is supplied to the microcomputer from the first power supply PWR1 and the second power supply PWR2.

  Each of the above devices is connected by three communication lines, T1 connecting the front wheel hydraulic brake control device 1, the brake main control device 2, the rear wheel electric brake units 4, 5, the brake main control device 2, and the regenerative brake. Communication is performed between T2 connecting the control device 7 and T3 connecting the brake main control device 2 and the other control device 6.

  The brake main control device 2 includes a front wheel hydraulic brake control device 1 and a rear wheel electric brake unit 4 based on the operation of the brake pedal BP and vehicle behavior (wheel speed, steering angle, yaw rate, front / rear G, lateral G, etc.). 5. The control command is transmitted to the regenerative brake control device 7 and the like. Specifically, normal control that increases braking force according to the depression force on the brake pedal BP, vehicle dynamics control system that controls vehicle behavior by brake fluid pressure, and wheel lock during braking is avoided by decompression control, etc. An anti-lock brake system, a traction control system that suppresses drive wheel slip caused by excessive torque of the drive wheel during driving, and the like are executed, and the brake braking force of each wheel is optimally controlled according to the driving situation.

[Details of power supply controller]
Next, the configuration of the power supply control circuit in the front wheel hydraulic brake control device 1 will be described. FIG. 2 is a configuration diagram of a power supply control circuit in the front wheel hydraulic brake control device 1.

  The front wheel hydraulic brake control device 1 includes a microcomputer 16 that controls a hydraulic pump, a motor, and the like that operate the hydraulic brake in the front wheel hydraulic brake unit 3. The microcomputer 16 corresponds to an electric actuator according to the present invention.

  The first power supply circuit 10 that supplies power from the first power supply PWR1 to the microcomputer 16 is provided with a first power supply relay circuit (first power supply switching means) 12 that switches between energization and interruption of the first power supply circuit 10. The second power supply circuit 11 that supplies power from the second power supply PWR2 to the microcomputer 16 is provided with a second power supply relay circuit (second power supply switching means) 14 that switches between energization and interruption of the second power supply circuit 11.

  The configuration of the first power relay circuit 12 is shown in FIG. As shown in FIG. 3, the first power supply relay circuit 12 includes a high-power metal oxide semiconductor field effect transistor (MOSFET) (hereinafter referred to as a power MOSFET) 12a, and resistors 12c and 12d. And a bipolar transistor 12e. When a signal from a first power supply relay trigger circuit 17 described later is input and this signal is Lo, a first power supply reverse connection prevention circuit 13 is provided by a parasitic diode 12b provided between the source and drain of the power MOSFET 12a. To the 5V power supply generation circuit 23 side. On the other hand, when the signal from the first power supply relay trigger circuit 17 is Hi, the source and drain of the power MOSFET 12a are short-circuited. The second power supply relay circuit 14 is also configured in the same manner as the first power supply relay circuit 12 by the power MOSFET 14a, the resistors 14c and 14d, and the transistor 14e.

  Between the first power supply relay circuit 12 and the first power supply PWR1, there is a first power supply reverse connection prevention circuit (first current backflow prevention means) 13 for preventing a current from flowing from the microcomputer 16 side to the first power supply PWR1 side. Provided. Between the second power supply relay circuit 14 and the second power supply PWR2, there is a second power supply reverse connection prevention circuit (second current backflow prevention means) 15 for preventing current from flowing from the microcomputer 16 side to the second power supply PWR2 side. Provided. The first power supply reverse connection prevention circuit is provided between the first power supply relay circuit 12 and the 5V power supply generation circuit 23, and the second power supply reverse connection prevention circuit is provided between the second power supply relay circuit 12 and the 5V power supply generation circuit 23. It may be provided.

  A diode is widely used as a means for preventing a reverse current flow. This is due to the rectifying action that the resistance is small for the forward current flow and the resistance is large for the reverse current flow. However, a voltage drop occurs because resistance occurs even in the forward current flow. Therefore, in the configuration in which the current that has passed through the diode is supplied to the microcomputer 16, for example, when the voltage drops, for example, during cranking, a voltage drop due to the diode further occurs, and the 5V power supply generation circuit 23 generates the 5V power supply. There is a possibility that a necessary voltage cannot be supplied. Therefore, there is a possibility that 5V voltage cannot be supplied to the microcomputer 16.

  Therefore, in this embodiment, a power MOSFET is used for the first power supply reverse connection prevention circuit 13 as shown in FIG. The first power supply reverse connection prevention circuit 13 includes a power MOSFET 13a, resistors 13c and 13d, and a bipolar transistor 13e. When a first power holding signal from a microcomputer 16 to be described later is input and the first power holding signal is Lo, a first diode PWR1 side is provided by a parasitic diode 13b provided between the source and drain of the power MOSFET 13a. To the first power supply relay circuit side. On the other hand, when the first power holding signal is Hi, the source and drain of the power MOSFET 13a are short-circuited. At this time, in the first power supply reverse connection prevention circuit 13, the current does not flow through the parasitic diode 13b but flows between the shorted source and drain, so that no voltage drop occurs.

  The second power supply reverse connection prevention circuit 15 is configured in the same manner as the first power supply reverse connection prevention circuit 13 by the power MOSFET 15a, resistors 15c and 15d, and the transistor 15e.

  The first power supply circuit 10 and the second power supply circuit 11 merge on the microcomputer 16 side with respect to the first power supply relay circuit 12 and the second power supply relay circuit 14, and for the microcomputer 16 between the junction and the microcomputer 16. 5V power supply generation circuit 23 for generating a 5V power supply.

  The first power supply relay circuit 12 energizes the first power supply circuit 10 when the Hi signal is input from the first power supply relay trigger circuit 17 and shuts off the first power supply circuit 10 when the Lo signal is input. When the Hi signal is input from the second power relay trigger circuit 18, the second power circuit 11 is energized, and when the Lo signal is input, the second power circuit 11 is shut off.

  A power relay simultaneous ON prohibition circuit (simultaneous energization preventing means) 19 is provided between the first power relay trigger circuit 17 and the second power relay trigger circuit 18. The power relay simultaneous ON prohibition circuit 19 is a circuit for prohibiting the first power relay circuit 12 and the second power relay circuit 14 from being simultaneously ON, that is, energizing.

  The power relay simultaneous ON prohibition circuit 19 inputs power from the first power supply PWR1 and a signal from the first power supply relay trigger circuit 17. The power relay simultaneous ON prohibition circuit 19 is connected to the second power relay trigger circuit 18 when the voltage is generated in the first power PWR1 and the signal from the first power relay trigger circuit 17 is Hi. Outputs a Hi signal, otherwise outputs a Lo signal.

  The configuration of the power relay simultaneous ON prohibition circuit 19 is shown in FIG. As shown in FIG. 5, the power relay simultaneous ON prohibition circuit 19 includes resistors 19a, 19b, and 19c and transistors 19d and 19e.

  When the power relay simultaneous ON prohibition circuit 19 inputs a Hi signal from the first power relay trigger circuit 17, it outputs a Lo signal to the second power relay trigger circuit 18. On the other hand, the power relay simultaneous ON prohibition circuit 19 is when the Lo signal is input from the first power relay trigger circuit 17, and when the voltage is generated in the first power PWR1, or the first power relay trigger circuit. When the Hi signal is input from 17 and no power is generated in the first power supply PWR1, the Hi power signal is output from the second power supply relay trigger circuit 18.

  The first power relay trigger circuit 17 receives a first power ignition switch signal, a wake-up signal, and a first power holding signal and a first power relay control signal described later from the microcomputer 16. The second power relay trigger circuit 18 includes a second power ignition switch signal, a wake-up signal, a second power holding signal and a second power relay control signal, which will be described later from the microcomputer 16, and a signal from the power relay simultaneous ON inhibition circuit 19. Enter.

  The configuration of the first power supply relay trigger circuit 17 is shown in FIG. As shown in FIG. 6, the first power supply relay trigger circuit 17 includes diodes 17a, 17b, and 17c, a resistor 17d, and a transistor 17e.

  When the first power supply relay control signal from the microcomputer 16 is Lo, the first power supply relay trigger circuit 17 is at least one of the first ignition switch signal, the wake-up signal, and the first power holding signal is Hi. If there is, output Hi signal. On the other hand, when the first power relay control signal is Hi, the Lo signal is output regardless of the first ignition switch signal, the wake-up signal, and the first power holding signal.

  The configuration of the second power supply relay trigger circuit 18 is shown in FIG. As shown in FIG. 7, the second power supply relay trigger circuit 18 includes diodes 18a, 18b, 18c, 18d, and 18e, a resistor 18f, and a transistor 18g.

  When both the second power relay control signal and the power relay simultaneous ON prohibition circuit 19 output are Lo signals, the second power relay trigger circuit 18 receives the second ignition switch signal, the wake-up signal, and the second power holding signal. If at least one of the signals is Hi, the Hi signal is output. On the other hand, if either the second power relay control signal or the power relay simultaneous ON prohibition circuit 19 output is Hi, the Lo signal is output regardless of the first ignition switch signal, the wake-up signal, and the first power holding signal. Output.

  The microcomputer 16 includes a first power supply monitor circuit 20 branched from between the first power supply PWR1 of the first power supply circuit 10 and the first power supply reverse connection prevention circuit 13, the second power supply PWR2 of the second power supply circuit 11, and the second power supply. The second power supply monitor circuit 21 branched from the reverse connection prevention circuit 15 is input. The first power supply monitor circuit 20 and the second power supply monitor circuit 21 monitor the voltage of each power supply. In addition, the microcomputer 16 receives the first power supply ignition switch signal, the second power supply ignition signal, and the wake-up signal and monitors each signal. Based on each of these input signals, the first power supply relay trigger circuit 17 generates a first power supply relay control signal and a second power supply relay control signal for instructing energization of the first power supply relay circuit 12 or the second power supply relay circuit 14. And output to the second power supply relay trigger circuit 18 respectively.

  With this configuration, it is possible to control the microcomputer 16 so that normal power is always supplied to the microcomputer 16 while monitoring the voltages of the first power supply PWR1 and the second power supply PWR2 after the microcomputer 16 is started.

  Further, the microcomputer 16 sends the first power supply holding signal and the second power supply holding signal to the first power supply relay trigger circuit 17 and the second power supply relay trigger circuit 18, and the first power supply reverse connection prevention circuit 13 and the second power supply reverse connection prevention circuit 15. Each signal is output. The first power holding signal and the second power holding signal are self-holding signals for supplying power to the microcomputer 16 for a predetermined time even after the first ignition switch, the second ignition switch, and the wakeup are turned off. While the self-holding signal is Hi, the first power supply reverse connection prevention circuit 13 and the second power supply reverse connection prevention circuit 15 are short-circuited, and the first power supply relay circuit 12 and the second power supply relay circuit 14 are in the current state ( In other words, it continues energization if energized and shuts off if energized.

  The microcomputer 16 finishes processing (stores a fail code, a correction value, etc.) for a fixed time after the first ignition switch, the second ignition switch, and the wakeup are turned off.

  In the present embodiment, as described above, the first power supply relay control signal and the second power supply relay control signal are output to the first power supply relay trigger circuit 17 and the second power supply relay trigger circuit 18, respectively. For example, consider a case where the first power relay circuit 12 and the second power relay circuit 14 are directly controlled by a control signal from the microcomputer 16. The output of the first power relay control signal and the second power relay control signal becomes unstable due to the runaway of the microcomputer 16 and the like, and a signal that energizes the first power relay circuit 12 and the second power relay circuit 14 at the same time is output. There is a risk of doing. At this time, when the first power supply circuit 10 and the second power supply circuit 11 are energized, one of the power supplies becomes abnormal due to a short circuit between the first power supply PWR1 and the second power supply PWR2, etc. There is a risk that the other normal power supply will be affected. Therefore, although the power supply is a dual system, even if only one power supply is abnormal, normal power supply cannot be performed. Therefore, the first power supply relay circuit 12 and the second power supply relay are provided from the microcomputer 16 via the first power supply relay trigger circuit 17 and the second power supply relay trigger circuit 18 provided with the power supply relay simultaneous ON prohibition circuit 19 therebetween. The circuit 14 is controlled.

  When the first power supply relay control signal and the second power supply relay control signal are simultaneously Hi, both the first power supply relay circuit 12 and the second power supply relay circuit 14 are cut off, and the microcomputer 16 supplies power. The situation will not be performed and the operation will be terminated. Therefore, in this embodiment, a simultaneous Hi output prohibiting circuit (simultaneous shut-off preventing means) 22 for prohibiting the first power relay control signal and the second power relay control signal from simultaneously becoming Hi signals is provided.

  The configuration of the simultaneous Hi output prohibition circuit 22 is shown in FIG. As shown in FIG. 8, the simultaneous Hi output prohibition circuit 22 includes resistors 22a and 22b, an AND circuit element 22c, and a transistor 22d.

  The simultaneous Hi output prohibition circuit 22 outputs both the first power relay control signal and the second power relay control signal as the Lo signal when both the first power relay control signal and the second power relay control signal output the Hi signal. To do.

  Next, the operation of the power supply control system of this embodiment will be described.

  9, FIG. 10 and FIG. 11 are flowcharts showing the control flow of the power supply control system in this embodiment.

  In step S1, external trigger switches such as a first ignition switch, a second ignition switch, and a wake-up signal are input, and a Hi signal is input.

  In step S2, the Hi signal of the external trigger switch is transmitted to the first power supply relay trigger circuit 17 and the second power supply relay trigger circuit 18, respectively.

  In step S <b> 3, the first power supply relay trigger circuit 17 outputs a Hi signal to the first power supply relay circuit 12 and the power supply relay simultaneous ON prohibition circuit 19. At this time, the first power supply relay circuit 12 is energized.

  In step S4, it is determined whether or not the voltage of the first power supply PWR1 is equal to or lower than a predetermined value. If it is not lower than the predetermined value, the process proceeds to step S5. If it is lower than the predetermined value, the process proceeds to step S6. . The determination in step S4 is performed by the power relay simultaneous ON prohibition circuit 19.

  In step S5, the power relay simultaneous ON prohibition circuit 19 transmits the Hi signal to the second power relay trigger circuit 18 and sets the output of the second power relay trigger circuit 18 to Lo. As a result, the second power supply relay circuit is cut off.

  In step S6, the power relay simultaneous ON prohibition circuit 19 transmits the Lo signal to the second power relay trigger circuit 18 and sets the output of the second power relay trigger circuit 18 to Hi. Thereby, the second power relay circuit is energized.

  In step S <b> 7, power is supplied to the microcomputer 16 by energization of the first power supply circuit 10 or the second power supply circuit 11, and control by the microcomputer 16 is started.

  In step S8, the first power supply monitor circuit input to the microcomputer 16 determines whether or not the voltage of the first power supply PWR1 is equal to or lower than a predetermined value. When it is larger than the predetermined value, the process proceeds to the power supply control from the first power supply in step S10 (FIG. 10), and when it is equal to or less than the predetermined value, the process proceeds to the power supply control from the second power supply in step S20 (FIG. 11).

  In step S11 of FIG. 10, the microcomputer 16 outputs the first power supply relay control signal Lo, that is, the energization command for the first power supply relay circuit, and the second power supply relay control signal is Hi, that is, the cutoff command for the second power supply relay circuit. Is output. This output signal is transmitted to the first power supply relay trigger circuit 17 and the second power supply relay trigger circuit 18, respectively.

  In step S <b> 12, the first power supply relay trigger circuit 17 transmits an external trigger and a Hi signal based on the first power supply holding signal to the first power supply relay circuit 12 to energize the first power supply relay circuit 12.

  In step S <b> 13, the second power supply relay trigger circuit 18 blocks the second power supply relay circuit 14 without transmitting the external trigger and the Hi signal based on the second power supply holding signal to the second power supply relay circuit 14. Steps S12 and S13 correspond to the normal time switching means of the present invention.

  In step S14, it is determined whether or not the power supply is held by the first power supply hold signal or the second power supply hold signal. If the power supply is held, the process proceeds to step S8. If not, the process proceeds to step S15. To do.

  In step S15, the microcomputer 16 outputs Hi signals as the first power holding signal and the second power holding signal. The first power holding signal and the second power holding signal are transmitted to the first power supply reverse connection prevention circuit 13 and the first power supply relay trigger circuit 17, and the second power supply reverse connection prevention circuit 15 and the second power supply relay trigger circuit 18. .

  In step S16, the first power supply reverse connection prevention circuit 13 and the second power supply reverse connection prevention circuit 15 are short-circuited. Step S16 corresponds to the short-circuit means of the present invention.

  In step S17, the first power supply relay trigger circuit 17 energizes the first power supply PWR1 and the first power supply relay circuit 12 in response to the input of the first power supply holding signal. Similarly, the second power supply relay trigger circuit 18 energizes the second power supply PWR2 and the second power supply relay circuit 14 in response to the input of the second power supply holding signal. By this action, the power supply can be held by the control signal from the microcomputer 16 after the microcomputer 16 is activated.

  In step S21 of FIG. 11, it is determined by the second power supply monitor circuit input to the microcomputer 16 whether the voltage of the second power supply PWR2 is equal to or lower than a predetermined value. When it is larger than the predetermined value, the process proceeds to step S17, and when it is less than the predetermined value, the process proceeds to step S8.

  In step S22, the microcomputer 16 outputs the first power supply relay control signal Hi, that is, the first power supply relay circuit cutoff command, and the second power supply relay control signal outputs Lo, that is, the second power supply relay circuit energization command. . This output signal is transmitted to the first power supply relay trigger circuit 17 and the second power supply relay trigger circuit 18, respectively.

  In step S <b> 23, the first power supply relay trigger circuit 17 blocks the first power supply relay circuit 12 without transmitting the external trigger and the Hi signal based on the first power supply holding signal to the first power supply relay circuit 12.

  In step S <b> 24, the second power supply relay trigger circuit 18 transmits the external trigger and the Hi signal based on the second power supply holding signal to the second power supply relay circuit 14 and energizes the second power supply relay circuit 14. Steps S24 and S25 correspond to the abnormal time switching means of the present invention.

  In step S25, it is determined whether or not the power supply is in a self-holding state. If it is in the self-holding state, the process proceeds to step S21, and if not in the self-holding state, the process proceeds to step S26.

  In step S26, the microcomputer 16 outputs Hi signals as the first power holding signal and the second power holding signal. The first power holding signal and the second power holding signal are transmitted to the first power supply reverse connection prevention circuit 13 and the first power supply relay trigger circuit 17, and the second power supply reverse connection prevention circuit 15 and the second power supply relay trigger circuit 18. .

  In step S27, the first power supply reverse connection prevention circuit 13 and the second power supply reverse connection prevention circuit 15 are short-circuited. Step S27 corresponds to the short-circuit means of the present invention.

  In step S28, the first power supply relay trigger circuit 17 energizes between the first power supply PWR1 and the first power supply relay circuit 12 in response to the input of the first power supply holding signal. Similarly, the second power supply relay trigger circuit 18 energizes the second power supply PWR2 and the second power supply relay circuit 14 in response to the input of the second power supply holding signal. By this action, the power supply can be held by the control signal from the microcomputer 16 after the microcomputer 16 is activated.

  12 and 13 are time charts for control of the power supply control device.

[When starting the ignition]
From time t1 to t2, the first power supply PWR1 and the second power supply PWR2 are normal and are activated by the first ignition switch and the second ignition switch.

  In this case, the first ignition switch is turned ON, and the first power supply relay circuit 12 is energized by the Hi signal of the first power supply relay trigger circuit 17. On the other hand, even if the second ignition switch is turned ON, the second power supply relay trigger signal is output by the power relay simultaneous ON prohibition circuit 19 so that the second power supply relay circuit 14 is cut off.

  After the microcomputer 16 is activated, the first power holding signal and the second power holding signal are output as Hi signals. When the first power holding signal and the second power holding signal are Hi, the first power supply reverse connection prevention circuit 13 and the second power supply reverse connection prevention circuit 15 are short-circuited.

  Further, after the microcomputer 16 is activated, the microcomputer 16 monitors the first power supply PWR1, the second power supply PWR2, the first ignition switch, and the second ignition switch. The microcomputer 16 keeps the first power holding signal and the second power holding signal Hi for a certain period of time after the first ignition switch and the second ignition switch are turned off, thereby enabling power supply to the microcomputer 16.

[When wake-up signal is activated]
From time t3 to t4, the first power supply PWR1 and the second power supply PWR2 are normal and are activated by a wakeup signal.

  In this case, since the wake-up signal is generated, the first power supply relay circuit 12 is energized by the Hi signal of the first power supply relay trigger circuit 17. On the other hand, even if the wake-up signal is input as the second power relay trigger signal, the power relay simultaneous ON prohibition circuit 19 outputs the Lo signal, so that the second power relay circuit 14 is cut off.

  After the microcomputer 16 is activated, the microcomputer 16 monitors the first power supply PWR1, the second power supply PWR2, and the wake-up signal. The microcomputer 16 keeps the first power holding signal and the second power holding signal Hi for a certain period of time after the wake-up signal is turned OFF, thereby enabling power supply to the microcomputer 16.

[When microcomputer runaway]
From time t5 to t6, a time chart when the microcomputer 16 runs away is shown.

  In this case, the outputs of the first power supply relay control signal, the second power supply relay control signal, the first power supply holding signal, and the second power supply holding signal are indefinite. 12 and the second power supply relay circuit 14 are prevented from being energized simultaneously. Further, the simultaneous Hi output prohibiting circuit 22 prevents the first power relay circuit 12 and the second power relay circuit 14 from being simultaneously cut off.

[First power failure before startup]
From time t7 to time t8 in FIG. 13, a case where a failure has occurred in the first power supply PWR1 before the microcomputer 16 is activated is shown.

  In this case, since the first ignition switch does not act, the first power supply relay trigger circuit 17 outputs a relay OFF command signal to the first power supply relay circuit 12. At this time, the power relay simultaneous ON prohibition circuit 19 outputs a signal permitting the energization of the second power relay circuit 14 and the second ignition switch is ON, so that the second power relay trigger circuit 18 is the second power relay. An ON command signal is output to the circuit 14.

  Since the first power supply relay circuit 12 is cut off and the second power supply relay circuit 14 is energized, power is supplied to the microcomputer 16 from the second power supply PWR2, and even if the first power supply PWR1 fails, the microcomputer 16 Can operate normally.

[Restore first power after startup]
From time t8 to t9, the first power supply PWR1 is recovered from the failure after the microcomputer 16 is activated.

  When the microcomputer 16 detects the voltage recovery of the first power supply PWR1 by the first power supply monitor circuit 20, the first power supply relay control signal outputs the first relay circuit ON command signal, and the second power supply relay control signal is the second relay. A circuit OFF command signal is output. The first power supply relay circuit 12 is energized, the second power supply relay circuit 14 is cut off, and the microcomputer 16 is operated by the power from the first power supply PWR1.

[First power failure after startup]
From time t9 to t10, the case where the first power supply PWR1 fails after the microcomputer 16 is activated is shown.

  When the microcomputer 16 detects the voltage drop of the first power supply PWR1 by the first power supply monitor circuit 20, the first power supply relay control signal outputs the first relay circuit OFF command signal, and the second power supply relay control signal is the second relay. A circuit ON command signal is output. Since the first power supply relay circuit 12 is cut off and the second power supply relay circuit 14 is energized, power is supplied to the microcomputer 16 from the second power supply PWR2, and even if the first power supply PWR1 fails, the microcomputer 16 Can operate normally.

  [Second power failure after startup]

  From time t10 to t11, the case where the second power supply PWR2 fails after the microcomputer 16 is started up is shown.

  When the microcomputer 16 detects the voltage drop of the second power supply PWR2 by the second power supply monitor circuit 20, the first power supply relay control signal outputs the first relay circuit ON command signal, and the second power supply relay control signal is the second relay. A circuit OFF command signal is output. The microcomputer 16 is continuously supplied with power from the first power supply PWR1, and the microcomputer 16 can operate normally even if a failure occurs in the second power supply PWR2.

  Next, the effect of the power supply control system in the present embodiment will be described.

  (1) After the microcomputer 16 is activated, the first power supply reverse connection prevention circuit 13 and the second power supply reverse connection prevention circuit 15 are short-circuited, and the 5V power supply generation circuit is generated from the first power supply PWR1 and the second power supply PWR2 without using a diode. To supply power. Therefore, since the voltage drop due to the diode does not occur after the microcomputer 16 is activated, the voltage drop can be suppressed to the minimum even in a situation where the voltage is lowered such as during cranking. Therefore, the 5V power supply generation circuit 23 can secure a voltage necessary for generating the 5V power supply, and the stop of the microcomputer 16 can be avoided.

  In the brake-by-wire system as in the present embodiment, the system is activated before cranking. Therefore, if the system stops due to a voltage drop during cranking, sufficient braking force may not be obtained, or pressure oil is introduced from the wheel cylinder side to the master cylinder side by opening the fail-safe valve, and the brake pedal BP kicks. There is a risk that the driver may feel uncomfortable due to the back. By introducing the power supply control system of the present invention into the brake-by-wire system, a sufficient braking force can be obtained, and the uncomfortable feeling to the driver can be reduced (corresponding to claim 1).

  (2) When the first power supply relay trigger circuit 17 outputs a signal for energizing the first power supply relay circuit 12 by the power supply relay circuit simultaneous ON prohibition circuit 19, the second power supply relay trigger circuit 17 A signal for shutting off the circuit 14 is output. Therefore, the first power supply relay circuit 12 and the second power supply relay circuit 14 are prevented from being energized at the same time, and the first power supply PWR1 and the second power supply PWR2 are short-circuited. When this happens, it is possible to prevent the normal power supply from being affected and a double failure from occurring (corresponding to claim 2).

  (3) After the microcomputer 16 is activated, the microcomputer 16 performs the first operation based on the voltage information of the first power supply PWR1 and the voltage information of the second power supply PWR2 input from the first power supply monitor circuit 20 and the second power supply monitor circuit 21. The energization or interruption of the power relay circuit 12 and the second power relay circuit 14 is controlled. Therefore, even when the first power supply PWR1 or the second power supply PWR2 fails or the voltage drops after the microcomputer 16 is activated, it can be switched to a normal power supply. Therefore, even if one of the first power supply PWR1 and the second power supply PWR2 fails or power is reduced during the operation of the microcomputer 16, power can be continuously supplied to the microcomputer 16 (corresponding to claim 3). ).

  (4) The microcomputer 16 does not directly control the first power relay circuit 12 and the second power relay circuit 14, but rather the first power relay via the first power relay trigger circuit 17 and the second power relay trigger circuit 18. The circuit 12 and the second power supply relay circuit 14 are controlled. Therefore, even if the microcomputer 16 outputs a command signal for energizing the first power relay circuit 12 and the second power relay circuit 14 at the same time, the second power relay trigger circuit 17 is A signal for shutting off the second power supply relay circuit 14 is output. Accordingly, it is possible to prevent the first power supply relay circuit 12 and the second power supply relay circuit 14 from being energized at the same time, and the first power supply PWR1 and the second power supply PWR2 are short-circuited. When this happens, it is possible to prevent the normal power supply from being affected and a double failure from occurring (corresponding to claim 4).

  (5) The first power supply relay control signal and the second power supply relay control signal of the microcomputer 16 simultaneously output a signal (Hi signal) that simultaneously cuts off the first power supply relay circuit 12 and the second power supply relay circuit 14. A simultaneous Hi output inhibition circuit 22 is provided to prevent this. Therefore, even if the microcomputer 16 outputs a command signal for simultaneously shutting off the first power relay circuit 12 and the second power relay circuit 14, the simultaneous Hi output prohibiting circuit 22 causes the first power relay control signal and the second power Both relay control signals output Lo signals. Therefore, it is possible to prevent the first power supply relay circuit 12 and the second power supply relay circuit 14 from being cut off at the same time, and to prevent the power supply from being cut off during the operation of the microcomputer 16 (corresponding to claim 5).

[Other embodiments]
As described above, the best mode for carrying out the present invention has been described based on the first embodiment and the second embodiment. However, the specific configuration of the present invention is not limited to each embodiment. Design changes and the like within a range that does not depart from the gist are also included in the present invention.

  For example, in the first embodiment, the configuration and control of the power supply control system in the front wheel hydraulic brake control device 1 have been described, but the same configuration and control may be used for the brake main control device 2.

  Moreover, you may use for the power supply control apparatus of the system which operate | moves with a power supply irrespective of a by-wire brake system.

1 is a system diagram showing an overall configuration of a brake system. It is a circuit block diagram of a front-wheel hydraulic brake control apparatus. It is a circuit block diagram of a 1st power supply relay circuit. It is a circuit block diagram of a 1st power supply reverse connection prevention circuit. It is a circuit configuration diagram of a power relay simultaneous ON prohibition circuit It is a circuit block diagram of a 1st power supply relay trigger circuit. It is a circuit block diagram of a 2nd power supply relay trigger circuit. It is a circuit block diagram of a simultaneous Hi output prohibition circuit. It is the flowchart which performed the control flow of the power supply control system. It is the flowchart which performed the control flow of the power supply control system when supplying power from the 1st power supply. It is the flowchart which performed the control flow of the power supply control system when supplying power from the 2nd power supply. It is a time chart of control of a power supply control system. It is a time chart of control of a power supply control system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front wheel hydraulic brake control apparatus 6 Control apparatus 10 1st power supply circuit 11 2nd power supply circuit 12 1st power supply relay circuit 13 1st power supply reverse connection prevention circuit 14 2nd power supply relay circuit 15 Power supply reverse connection prevention circuit 16 Microcomputer 17 1st power supply Relay trigger circuit 18 Second power relay trigger circuit 19 Power relay circuit simultaneous ON prohibit circuit 20 First power monitor circuit 21 Second power monitor circuit 22 Simultaneous Hi output prohibit circuit
PWR1 1st power supply
PWR2 Second power supply

Claims (5)

A first power source;
A second power source;
An electric actuator driven by electric power supplied from the first power source or the second power source;
A first power supply circuit for supplying power from the first power supply to the electric actuator;
A second power supply circuit for supplying power from the second power supply to the electric actuator;
In a power supply control system comprising:
First power supply switching means for switching between energization and interruption of the first power supply circuit;
Second power supply switching means for switching between energization and shutoff of the second power supply circuit;
When the first power supply is normal, the normal-time switching control means for energizing the first power supply circuit and shutting off the second power supply circuit;
An abnormal time switching means for shutting off the first power supply circuit and energizing the second power supply circuit when the first power supply is abnormal;
First power supply backflow prevention means for preventing backflow of current in the first power supply circuit;
Second power supply backflow prevention means for preventing backflow of current in the second power supply circuit;
Short-circuit means for short-circuiting the first power supply backflow prevention means and the second power supply backflow prevention means after starting the electric actuator;
A power supply control system comprising: The power supply control system according to claim 1,
A power supply control system comprising a simultaneous energization preventing means for preventing the first power supply switching means and the second power supply switching means from being energized simultaneously. In the power supply control system according to claim 1 or 2,
A first power supply monitor circuit for inputting voltage information of a first power supply to the electric actuator;
A second power supply monitor circuit for inputting voltage information of a second power supply to the electric actuator;
With
After the electric actuator is activated, the electric actuator controls energization or interruption of the first power supply switching means and the second power supply switching means based on the voltage information of the first power supply and the voltage information control signal of the second power supply. A power control system. In the power supply control system according to claim 3,
The power supply control system, wherein the electric actuator controls the first power relay circuit and the second power relay circuit through the simultaneous energization preventing means. In the power supply control system according to claim 3 or 4,
A power supply control system comprising: a simultaneous shut-off preventing means for preventing the electric actuator from outputting a control signal for simultaneously shutting off the first power supply circuit and the second power supply circuit.

Images