JP2017208898A - Electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle equipped with a regenerative brake system, which can secure regenerative braking force while avoiding overcharge of a power storage device at the time when a sensor detects a target under running.SOLUTION: In an electric vehicle 5, a motor generator 30 having a rotor mechanically connected to wheels 55 can execute regenerative control by which regenerative braking force is generated together with power generation. Auxiliary machinery loads 80 and 210 are electrically connected from the motor generator 30 to a power conversion path between power storage devices 10. A control device 100 calculates a risk degree parameter Pdg for quantitatively estimating a risk degree of a collision with a target outside a vehicle on the basis of output of a target detection sensor 110. The control device 100 executes regenerative control together with forced operation control by which at least part of auxiliary machinery loads to which user operation is not inputted of the auxiliary machinery loads 80 and 210 is activated, if the risk degree parameter exceeds a determined value as the risk degree of the collision increases.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric vehicle, and more particularly to an electric vehicle having a regenerative braking system.

  Conventionally, in an electric vehicle equipped with a drive motor such as an electric vehicle or a hybrid vehicle, a regenerative brake system that covers part or all of the vehicle braking force by generating a negative torque accompanied by regenerative power generation by the drive motor. Is used.

  In Japanese Patent Laid-Open No. 6-165304 (Patent Document 1), in a regenerative braking system linked to an obstacle detection device, when an alarm signal is detected that detects the presence of an obstacle, the current value of the field coil is set to the maximum value. A control for performing automatic braking by increasing is described.

JP-A-6-165304

  However, with automatic braking according to Patent Document 1, when the risk of collision with an obstacle increases, the regenerative braking force can be ensured to the maximum while the power storage device may be deteriorated due to overcharging. In particular, it is known that in a lithium ion secondary battery in which an in-vehicle power storage device is being applied, deterioration continues due to deposition of lithium metal in the negative electrode of the lithium ion secondary battery when the high charge state continues. .

  On the other hand, since the regenerative brake is more responsive than a mechanical brake that is operated by hydraulic pressure, it is important to ensure that the regenerative brake is secured to the maximum in situations where an approach to an obstacle is detected by a sensor. It is preferable from the point of avoidance.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a power storage device for a vehicle equipped with a regenerative braking system when a target is detected during traveling by a sensor. This is to secure the regenerative braking force while avoiding overcharge.

  An electric vehicle according to the present invention includes a drive motor having a rotor mechanically connected to wheels, a power storage device, a detector, a plurality of auxiliary loads, and a control device. The power converter is connected between the driving motor and the power storage device, and is configured to control the output of the driving motor by bidirectional power conversion accompanied by charging / discharging of the power storage device. The detector is configured to detect a target outside the vehicle. The plurality of auxiliary machine loads are electrically connected to a power conversion path between the drive motor and the power storage device, and operate according to a user operation. The control device executes regenerative control that controls the power converter so that the drive motor outputs the braking torque of the vehicle by regenerative power generation. Further, the control device calculates a parameter value for quantitatively evaluating the collision risk to the target, and when the parameter value exceeds a determination value in accordance with an increase in the collision risk, The regenerative control is executed together with the forced operation control for operating at least a part of the auxiliary load on which no user operation is input.

  According to the electric vehicle, when the collision risk with respect to a target outside the vehicle is increased, the regeneration control can be executed with the forced operation control of the auxiliary load. Therefore, the increase in power consumption in the entire auxiliary load can alleviate the upper limit value of regenerative power within a limit range that protects the power storage device from overcharging. As a result, the regenerative braking force can be ensured while avoiding overcharging of the power storage device.

  Preferably, at the time of execution of the forced operation control, the control device increases the power consumption by the plurality of auxiliary machine loads in a stepwise manner according to the continuation of the charged state of the power storage device.

  In this way, it is possible to prevent a sudden change in the regenerative braking force for overcharge protection of the power storage device during execution of continuous regenerative control, which is typified when the automatic brake is turned on.

  Preferably, the control device does not execute the forced operation control during the operation of the predetermined automatic operation function even if the parameter value exceeds the determination value.

  In this case, if the auxiliary load is actuated unnecessarily such as when approaching a preceding vehicle due to deceleration by auto-cruise control or approaching an adjacent vehicle during parking assist control, there is a risk of adversely affecting the surroundings of the vehicle. In the scene, the forced operation control can be turned off.

  According to the present invention, in a vehicle equipped with a regenerative braking system, regenerative braking force can be ensured while avoiding overcharging of the power storage device when a target is detected by the sensor during traveling.

It is a schematic block diagram illustrating a configuration example of an electric vehicle according to an embodiment of the present invention. It is a conceptual diagram explaining the operation example of the automatic brake in the electric vehicle according to embodiment of this invention. It is a state transition diagram of the automatic brake in the electric vehicle according to the embodiment of the present invention. It is a flowchart explaining the forced operation | movement control of the auxiliary machine load in the electric vehicle according to this Embodiment. It is a conceptual diagram explaining the example of an operation | movement of the forced operation control of auxiliary machinery load. It is a conceptual diagram explaining an example of the change of the charging operation point of the electrical storage apparatus in regeneration control. It is a flowchart explaining the forced operation control of the auxiliary machine load in the electric vehicle according to the modification of this Embodiment. It is a conceptual diagram explaining the example of a raise of a danger parameter at the time of application of auto-cruise control (ACC) and traffic jam assist control (TJA). It is a conceptual diagram explaining the raise example of the risk parameter at the time of application of speed management control. It is a conceptual diagram explaining the example of a raise of the risk parameter at the time of application of parking assist control.

  Embodiments of the present invention will be described below in detail with reference to the drawings. In the following, the same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated in principle.

  FIG. 1 is a schematic block diagram illustrating a configuration example of an electric vehicle according to an embodiment of the present invention.

  Referring to FIG. 1, electric vehicle 5 includes a motor generator 30 and an engine 40 as power sources. The engine 40 generates mechanical energy obtained by converting heat energy generated by fuel combustion such as gasoline. Engine 40 and the rotor (not shown) of motor generator 30 are mechanically connected to wheels 55 via power distribution mechanism 50. Then, the motor generator 30 and the engine 40 operate cooperatively to generate the rotational force of the wheels 55, that is, the driving force of the electric vehicle 5. That is, the motor generator 30 is provided as a “driving motor”.

  The electric vehicle 5 further includes a power supply system 6. The power supply system 6 is configured to supply two types of voltages, a high voltage and a low voltage, to each device mounted on the electric vehicle 5. The power supply system 6 includes a high-voltage power storage device 10, an SMR (System Main Relay) 15, a power control unit (PCU) 20, and a control device 100.

  The high-voltage power storage device 10 can be composed of a rechargeable secondary battery such as nickel hydride or lithium ion. Therefore, hereinafter, power storage device 10 is also referred to as main battery 10. The rated output voltage of the main battery 10 is, for example, about 200 (V).

  Note that the power storage device 10 can be configured by another power storage element such as an electric double layer capacitor instead of the secondary battery. The main battery 10 is provided with a monitoring unit 11 including sensors for detecting voltage, current and temperature. Detection values (voltage, current and temperature) detected by the monitoring unit 11 are sent to the control device 100.

  The positive terminal of main battery 10 is electrically connected to power line PL, and the negative terminal of main battery 10 is connected to power line NL. SMR 15 is connected to power lines PL and NL. PCU 20 is electrically connected to main battery 10 via power lines PL and NL via SMR 15. Therefore, main battery 10 can be electrically disconnected from the drive system including PCU 20 by opening (off) SMR 15.

  High-voltage auxiliary loads 80 (1) to 80 (m) that operate at the voltage of main battery 10 are connected to power line PL (m: a natural number of 2 or more). For example, the auxiliary machine loads 80 (1) to 8 (m) include an inverter for driving the compressor of the air conditioner (not shown). Hereinafter, when the auxiliary loads 80 (1) to 80 (m) are comprehensively indicated, they are also simply referred to as auxiliary loads 80.

  The PCU 20 is configured to control the output (torque, rotation speed) of the motor generator 30 by executing bidirectional power conversion between the main battery 10 and the motor generator 30. The PCU 20 includes, for example, an inverter (not shown) for DC / AC power conversion. Alternatively, PCU 20 may be configured such that a converter (not shown) capable of boosting the output voltage of main battery 10 is further arranged between main battery 10 and an inverter (not shown).

  By controlling the motor generator 30 to output a positive torque by the PCU 20, the electric vehicle 5 can generate a driving force in the forward direction. Alternatively, when the electric vehicle 5 is decelerated due to a brake pedal operation or the like, the motor generator 30 can generate regenerative power by negative power acting on the wheels 55. For example, during deceleration, PCU 20 controls the output of motor generator 30 so as to generate braking torque (torque in a direction that prevents rotation of wheel 55). The PCU 20 converts the regenerative power generated by the motor generator 30 into charging power for the main battery 10 and outputs it between the power lines PL and NL.

  Further, the electric vehicle 5 includes a braking mechanism 60 that generates a mechanical friction braking force. The braking mechanism 60 includes a brake caliper 61 and a disc-shaped brake disc 62. The brake disc 62 is fixed so that the drive shaft of the wheel 55 and the rotation shaft coincide. The brake caliper 61 includes a wheel cylinder and a brake pad (not shown). When the hydraulic pressure is supplied from the brake hydraulic circuit 70 to the brake caliper 61, the wheel cylinder operates. The actuated wheel cylinder presses the brake pad against the brake disc 62, so that the rotation of the brake disc 62 is limited. Thus, the braking mechanism 60 generates a mechanical vehicle braking force in response to the hydraulic pressure supply from the brake hydraulic circuit 70 controlled by the control device 100. Hereinafter, in order to distinguish the braking force generated by the braking mechanism 60 from the regenerative braking force by the motor generator 30, it is also referred to as mechanical braking force. In the electric vehicle 5, the vehicle braking force can be secured by a combination of the regenerative braking force and the mechanical braking force.

  The control device 100 is configured by an electronic control unit (ECU) and controls the operation of the power supply system 6. Specifically, the control device 100 controls the opening / closing of the SMR 15 and the operation of the PCU 20. Furthermore, the control device 100 manages the charge / discharge and state of charge (SOC) of the main battery 10 based on the detected values of the voltage, current, and temperature of the main battery 10 from the monitoring unit 11.

  The accelerator opening sensor 101 detects the opening (accelerator opening) of an accelerator pedal (not shown) and outputs a signal Ac indicating the detection result. The brake pedal sensor 102 detects the operation state of a brake pedal (not shown) and outputs a signal Br indicating the detection result. The vehicle speed sensor 103 detects the speed of the electric vehicle 5 and outputs a signal Vv indicating the detection result. Signals Ac, Br, and Vv from the accelerator opening sensor 101, the brake pedal sensor 102, and the vehicle speed sensor 103 are input to the control device 100. The control device 100 controls the outputs of the motor generator 30, the engine 40, and the braking mechanism 60 so that the driving force or the braking force is applied to the electric vehicle 5 according to the operation of the accelerator pedal and the brake pedal by the user. Thereby, the vehicle travel along user operation is realized.

  The power supply system 6 further has a low voltage system configuration for generating a power supply voltage of an auxiliary load that operates at a voltage lower than the output voltage of the main battery 10. Specifically, the power supply system 6 includes a DCDC converter 200 and an auxiliary battery 250 for a low voltage system. The output voltage of auxiliary battery 250 is, for example, about 12V.

  DCDC converter 200 steps down the DC voltage on power line PL and outputs the voltage between power supply line PXL and ground line GL. The output voltage of DCDC converter 200 is controlled in accordance with voltage command value Vdc * from control device 100.

  A negative electrode terminal of auxiliary battery 250 is connected to ground wiring GL. On the other hand, the positive terminal of auxiliary battery 250 is electrically connected to power supply wiring PXL. Further, low-voltage auxiliary machine loads 210 (1) to 210 (n) are connected to the power supply wiring PXL (n: a natural number of 2 or more). Auxiliary equipment loads (constant voltage system) 210 (1) to 210 (n) include lighting fixtures such as headlamps, tail lamps and hazard lamps, wipers, small motors for opening / closing doors, horns for crans, indoor air conditioning Devices (fans), audio devices, and the like are included. Furthermore, the power supply wiring PXL is also connected to the control device 100. That is, the control device 100 is also operated by a low-voltage power supply voltage. Hereinafter, when the auxiliary machine loads 210 (1) to 210 (n) are comprehensively indicated, they are also simply referred to as auxiliary machine loads 210.

  As described above, the high voltage auxiliary load 80 and the low voltage auxiliary load 210 are electrically connected to the power lines PL and NL on the power conversion path between the motor generator 30 and the main battery 10 by the PCU 20. ing. Therefore, the accumulated power of main battery 10 and / or the power generated by motor generator 30 (regenerative power) is consumed by the operation of auxiliary loads 80 and 210.

  The operation switch 105 is used by the user to directly or indirectly operate and stop the high-voltage auxiliary load 80 (1) to 80 (m) and the low-voltage auxiliary load 210 (1) to 210 (n). This is a comprehensive notation of switches for instructing automatically. For example, the operation switch 105 commands a switch for direct activation / deactivation of each lighting fixture such as a headlight, and an on / off of automatic control of activation / deactivation of each lighting fixture in accordance with illuminance around the vehicle. Includes switch.

  The control device 100 controls the operation of the auxiliary machine loads 80 (1) to 80 (m) and 210 (1) to 210 (n). Basically, in response to a user operation on the operation switch 105, the control device 100 controls the operation and stop of each of the auxiliary machine loads 80 (1) to 80 (m) and 210 (1) to 210 (n). To do.

  Furthermore, the electric vehicle 5 is provided with an alarm output device 120 for outputting an alarm that the driver can recognize visually and / or auditoryly. The alarm output unit 120 includes a warning light, a speaker, and the like, and is controlled by the control device 100 to output an alarm to the driver.

  The electric vehicle 5 is further provided with a target detection sensor 110 for detecting a target (including a pedestrian, a stationary object, a preceding vehicle, a succeeding vehicle, or the like) that is a collision target outside the vehicle. The target detection sensor 110 corresponds to the “detector” embodiment, and may have any configuration as long as the target outside the vehicle can be detected. For example, a configuration in which a target is detected by a combination of a millimeter wave sensor and a camera (monocular camera or stereo camera) is known.

  Based on the detection result of the target detection sensor 110, the control device 100 calculates a risk parameter Pdg obtained by quantifying the risk of collision with the target of the electric vehicle 5. Parameters that quantify the collision risk include collision margin time (TTC: Time-To-Collision), stop margin (MTC: Margin-To-Collision), inter-vehicle time (THW: Time-Headway), or visual The degree of risk (KdB) and the like are known, and the risk level parameter Pdg can be calculated by appropriately adopting these indexes. In the present embodiment, it is assumed that the risk parameter Pdg has a higher collision risk as the value is higher. For example, the reciprocal of the collision margin time (1 / TTC) can be used as the risk parameter Pdg.

  In the electric vehicle 5, automatic brake control for automatically generating vehicle braking force based on the detection result by the target detection sensor 110 is executed.

FIG. 2 is a conceptual diagram for explaining an operation example of automatic braking in the electric vehicle 5.
Referring to FIG. 2, a stationary obstacle 300 in front of electric vehicle 5 is detected as a target by target detection sensor 110 (FIG. 1). At time t1, since the distance to the obstacle 300 is long, the risk parameter Pdg is almost zero.

  Thereafter, the risk parameter Pdg increases as the electric vehicle 5 approaches the obstacle 300. At time t2, when the risk parameter Pdg exceeds the threshold value Pt1, a warning is notified to the driver using the alarm output device 120 (FIG. 1).

  At time t3, when the electric vehicle 5 further approaches the obstacle 300, the automatic brake is turned on in response to the risk parameter Pdg exceeding the threshold value Pt2. When the automatic brake is turned on, even if a brake pedal (not shown) is not operated by the driver, the vehicle is automatically controlled by the control of the braking mechanism 60 and / or the motor generator 30 (PCU 20) by the control device 100. A braking force is generated.

  The automatic brake started at the time t3 is a relatively gentle brake for automatically decelerating the electric vehicle 5. At time t4, when the risk parameter Pdg further increases and exceeds the threshold value Pt3, the automatic brake is controlled so that the maximum braking force is output for collision avoidance.

FIG. 3 shows the state transition of the automatic brake in the electric vehicle 5.
As shown in FIG. 3, the automatic brake is turned off in the default state. When the risk parameter Pdg exceeds the threshold value Pt2, the automatic brake is turned on by satisfying the start condition. Once the automatic brake is turned on, the vehicle braking force is increased according to the increase in the risk parameter Pdg regardless of the operation of the brake pedal. When it is confirmed that the electric vehicle 5 is stopped after the automatic brake is turned on (Vv = 0), the automatic brake returns to the off state.

  The vehicle braking force in the automatic brake can also be output by a combination of the mechanical braking force by the braking mechanism 60 and the regenerative braking force by the motor generator 30 as described in FIG. Since the regenerative braking force has higher responsiveness than the mechanical braking force, it is preferable to secure the regenerative braking force in automatic braking.

  On the other hand, since the generation of the regenerative braking force is accompanied by the generation of the charging power of the main battery 10, it is necessary to limit the regenerative braking force within a range where the main battery 10 is not overcharged. In general, in consideration of the state of the main battery 10 (SOC and charging history), the charging power upper limit value Win is set so that overcharging is avoided. Then, the torque command value of motor generator 30 is set within a range where charging power exceeding charging power upper limit value Win does not occur. If the regenerative braking force subject to the above restriction is insufficient with respect to the vehicle braking force according to the driver's brake pedal operation or the vehicle braking force set by automatic braking, the shortage is generated by the braking mechanism 60. By doing so, it becomes possible to ensure a required vehicle braking force.

  In particular, when the main battery 10 is a lithium ion battery, the negative electrode potential of the lithium ion secondary battery is lowered to the lithium reference potential due to the generation of an excessive charging current, particularly the continuous charging current. Lithium metal may be deposited. For this reason, it is preferable to set the charging power upper limit Win based not only on the simple SOC and battery temperature but also on the history of the charging current.

  As described above, in order to protect the main battery 10, while securing the regenerative braking force is limited, in a situation where the risk of collision is increased due to an increase in the risk parameter Pdg, a highly responsive regenerative braking force is used. Thus, it is preferable to generate a vehicle braking force. Therefore, in the electric vehicle according to the present embodiment, the auxiliary load forcible operation control is combined with the regenerative control as follows.

  FIG. 4 is a flowchart illustrating forcible operation control of the auxiliary machine load in the electric vehicle according to the present embodiment. The control process shown in FIG. 4 is periodically executed by the control device 100.

  Referring to FIG. 4, control device 100 determines whether or not regenerative control is being performed in step S100. When regenerative braking force is generated by motor generator 30, step S100 is determined as YES, and the process proceeds to step S110. At the time of regenerative control, the setting of the vehicle braking force including the distribution of the mechanical braking force and the regenerative braking force, and the control of the braking mechanism 60 and / or the motor generator 30 (PCU 20) according to the setting are performed by a control process separate from FIG. Is executed. The automatic brake control described in FIGS. 2 and 3 is also reflected in the setting of the vehicle braking force.

  In step S110, the control device 100 compares the risk parameter Pdg with the threshold value Pt. The threshold value Pt is preferably set to Pt> Pt2 (for example, Pt = Pt3) for interlocking with the automatic brake control. The risk parameter Pdg is periodically calculated for the automatic brake control.

  When Pdg> Pt (when YES is determined in S110), control device 100 proceeds to step S120 to turn on the auxiliary operation load forced operation control. The forcible operation control of the auxiliary machine load means that the vehicle travels from the auxiliary voltage load 210 (1) to 210 (n) and the auxiliary machine load 80 (1) to 80 (m) of the voltage system shown in FIG. Even if no operation command is input from the user by the operation switch 105, the device that does not adversely affect the operation is automatically operated by the command from the control device 100. For example, as shown in FIG. 5, the headlight 91 and / or the tail lamp 92 included in the low-voltage auxiliary loads 210 (1) to 210 (n) are forcibly activated (lighted).

  In step S130, control device 100 determines an auxiliary load to be forcibly actuated based on the state of main battery 10. For example, by setting a plurality of types of operation patterns of auxiliary machine loads in advance and selecting an operation pattern according to the charge margin at that time, the auxiliary machine load to be forcibly operated can be determined. . The charge power upper limit value Win may be used as the charge margin, and a parameter that quantitatively indicates the risk of overcharge may be separately defined based on the charge current history or the like.

  In step S130, the power consumption due to the auxiliary load that is the target of forced operation is further estimated. This power consumption can be set in advance for each operation pattern. Further, in the regenerative control, the regenerative torque (that is, regenerative braking force) generated by the motor generator 30 is set in consideration of the power consumption due to the auxiliary machine load.

  As the auxiliary load to be forcibly actuated is increased and the power consumption in the entire auxiliary load is increased, the electric power used for charging the main battery 10 from the electric power generated by regenerative braking decreases. As a result, the power obtained by subtracting the power consumed by the auxiliary load from the regenerative power only needs to be limited within a range that does not exceed the charging power upper limit Win, so that regenerative power exceeding the charging power upper limit Win is generated. As described above, the regenerative braking force can be set. That is, the upper limit value of the regenerative braking force for protecting the main battery 10 from overcharging can be relaxed by turning on the auxiliary load forced operation control.

  When the risk parameter Pdg does not exceed the threshold value Pt (when NO is determined in S110), the control device 100 turns off the auxiliary load forced operation control in step S140. In this case, in response to a user command from the operation switch 105, the operation / stop of each of the auxiliary machine loads 80 (1) to 80 (m) and 210 (1) to 210 (n) is controlled. Even when the regeneration control is not executed (NO in S100), the auxiliary load forced operation control is turned off.

  As described above, in the electric vehicle according to the present embodiment, when the risk of collision with the target outside the vehicle is increased, the regenerative control can be executed with the forced operation control of the auxiliary machine load. Therefore, the upper limit value of the regenerative power within the limit range that protects the main battery 10 from overcharging can be relaxed by increasing the power consumption of the entire auxiliary load. As a result, it is possible to ensure the maximum regenerative braking force while avoiding overcharging of the power storage device. Thereby, for example, by securing the regenerative braking force when the automatic brake is activated, it is possible to achieve both protection from overcharging of the power storage device and improvement in collision avoidance performance.

  As shown in the example of FIG. 5, when the target of the forced operation is the headlight 91 and / or the tail lamp 92, it is possible to execute alerting to the outside of the vehicle in a situation where the risk of collision is increasing.

FIG. 6 shows a change example of the operating point of the main battery 10 during the regeneration control.
Referring to FIG. 6, a combination of charging power (current) and charging duration time at the power (current) is shown as an operating point when charging main battery 10. In FIG. 6, as an example of the overcharge risk determination, the charge limit line 500 is set as a set of limit values of the charge duration for each charge power (charge current).

  In the main battery 10, charging at an operating point in a region below the charging limit line 500 corresponds to charging in a safe use region where deterioration progress is avoided. On the other hand, the charging at the operating point in the upper region of the charging limit line 500 corresponds to the charging in the dangerous use region where the deterioration of the main battery 10 may occur. For example, in a lithium ion secondary battery, risk determination as shown in FIG. 6 is adopted as a method for evaluating a so-called charging depth.

  When the regenerative control of the electric vehicle 5 is continued, the main battery 10 is continuously charged. Typically, such continuous charging is performed when the automatic brake is on. First, when charging with the electric power P1 continues for T1 (charging operation point 501), the charging electric power of the main battery 10 is reduced to P2 in order to avoid charging in the dangerous use region. Thereafter, when the main battery 10 reaches the charging operation point 502 by continuing the charging with the electric power P2, the charging electric power is further reduced to P3, so that the charging in the dangerous use region can be avoided. However, considering the difference in responsiveness between the regenerative braking force and the mechanical braking force, it is preferable to avoid a sharp change in the regenerative braking force at this time.

  Therefore, the charging power is determined by determining the auxiliary load in step S130 (FIG. 4) so that the power consumption of the entire auxiliary load is increased from Px1 to Px2 when the charging power from the charging operation point 501 changes. It is possible to mitigate a decrease in regenerative electric power, that is, a decrease in regenerative braking force that accompanies this decrease.

  Similarly, by determining the auxiliary load in step S130 (FIG. 4) so that the power consumption of the entire auxiliary load is increased from Px2 to Px3 when changing from the charging operation point 502 to the charging power, A decrease in regenerative power accompanying a decrease in charging power, that is, a decrease in regenerative braking force can be mitigated.

  In this way, it is possible to prevent the regenerative braking force from changing sharply for overcharge protection of the main battery 10 during execution of continuous regenerative control, which is typically performed when the automatic brake is on.

[Modification]
Various controls have been proposed as automatic driving support control for vehicles. In these automatic driving support controls, the collision risk is not so high compared to normal driving even when approaching a target, such as deceleration for maintaining the distance when approaching a curve or driving support control during parking. There is a case.

  In such a case, if an auxiliary machine load such as a headlamp is forcibly operated as described above, there is a risk of adversely affecting the surroundings. For this reason, as a modification of the embodiment, a description will be given of a control in which the auxiliary load forced operation control is not executed when a predetermined automatic operation mode is applied.

  FIG. 7 is a flowchart illustrating forced operation control of an auxiliary machine load in an electric vehicle according to a modification of the present embodiment. The control process shown in FIG. 7 can also be periodically executed by the control device 100.

  FIG. 7 is compared with FIG. 4, in the modified example of the embodiment, whether the control device 100 is applying the predetermined automatic operation mode in step S105 during the regeneration control (YES in S100). It is determined whether or not.

  When the predetermined automatic operation mode is selected (YES in S105), control device 100 advances the process to step S140 so as not to execute the auxiliary load control. Thereby, even if the risk parameter Pdg becomes higher than the threshold value Pt, the forced operation control of the auxiliary machine load is not executed.

  For example, the predetermined operation mode includes auto cruise control (ACC) and traffic jam assist control (TJA) shown in FIG. 8, speed management control shown in FIG. 9, and parking assist control shown in FIG. .

  Referring to FIG. 8, when auto cruise control (ACC) or traffic jam assist control (TJA) is applied, electric vehicle 5 travels following preceding vehicle 5 x detected by target detection sensor 110. For this reason, automatic deceleration is performed to adjust the inter-vehicle distance when the preceding vehicle 5x is decelerated, such as during a curve run. At this time, the risk parameter Pdg increases in accordance with the approach of the preceding vehicle 5x.

  Referring to FIG. 9, when speed management control is applied, electric vehicle 5 is automatically decelerated when approaching a sharp curve. At this time, the risk parameter Pdg increases in accordance with the approach to the obstacle 5z such as a guardrail.

  Referring to FIG. 10, when parking assist control is applied, electrically powered vehicle 5 moves forward from vehicle position PS1 to PS2, temporarily travels backward, then moves forward again to vehicle position PS3, and then travels backward to vehicle position PS4. As such, guidance for the driver is provided. While moving the electric vehicle 5 according to such guidance, the risk parameter Pdg increases according to the approach to the adjacent vehicles 5x and 5y.

  When the operation control of the compulsory auxiliary load such as lighting of the headlight 91 is turned on in response to the increase of the risk parameter Pdg in the scenes as shown in FIGS. By giving, there exists a possibility of inhibiting a smooth vehicle driving on the contrary. Therefore, in the modification shown in FIG. 7, when the predetermined automatic operation mode as described above is applied, the forced operation control of the auxiliary machine load accompanying the increase in the risk parameter is kept off. Thereby, in addition to the effect by this Embodiment mentioned above, the smooth driving | operation at the time of application of a specific automatic driving mode is realizable.

  In the present embodiment, the hybrid vehicle is exemplified as the electric vehicle 5. However, if the drive motor is installed, the present invention is realized by an electric vehicle or a fuel cell vehicle in which the engine 40 is omitted. It is also possible to configure an electric vehicle 5 to which the above is applied.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  5 Electric vehicle (own vehicle), 5x, 5y Other vehicle, 5z, 300 Obstacle, 6 Power supply system, 10 Main battery (power storage device), 11 Monitoring unit, 30 Motor generator, 40 Engine, 50 Power distribution mechanism, 55 wheels , 60 Brake mechanism, 61 Brake caliper, 62 Brake disc, 70 Brake hydraulic circuit, 80 (1) to 80 (m) Auxiliary load (high voltage system), 91 Headlight, 92 Tail lamp, 100 Control device, 101 Open accelerator Degree sensor, 102 Brake pedal sensor, 103 Vehicle speed sensor, 105 Operation switch, 110 Target detection sensor, 120 Alarm output device, 200 Converter, 210 (1) to 210 (n) Auxiliary load (low voltage system), 250 Machine battery, 500 charge limit line, GL ground wiring, NL, P L power line, PS1 to PS4 vehicle position, PXL power wiring, Pdg risk parameter, Pt, Pt1 to Pt3 thresholds.

Claims (3)

A drive motor having a rotor mechanically coupled to the wheels;
A power storage device;
A power converter connected between the drive motor and the power storage device for controlling the output of the drive motor by bidirectional power conversion accompanied by charging and discharging of the power storage device;
A detector for detecting a target outside the vehicle;
A plurality of auxiliary loads that are electrically connected to a power conversion path between the drive motor and the power storage device and operate according to a user operation;
A controller for performing regenerative control for controlling the power converter so that the driving motor outputs braking torque of the vehicle by regenerative power generation;
The control device calculates a parameter value for quantitatively evaluating a collision risk to the target, and when the parameter value exceeds a determination value in accordance with an increase in the collision risk, the plurality of auxiliary machines An electric vehicle that executes the regenerative control together with a forced operation control that operates at least a part of an auxiliary load that is not input by the user operation among the loads.   2. The electric vehicle according to claim 1, wherein, when the forced operation control is executed, the control device gradually increases power consumption by the plurality of auxiliary loads according to a continuation of a charging state of the power storage device. .   3. The electric motor according to claim 1, wherein the control device does not execute the forced operation control during the regenerative control even when the parameter value exceeds a determination value during application of a predetermined automatic operation mode. vehicle.

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