JP2014239602A - Vehicle controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the service life of a capacitor while shortening waiting time of starter starting.SOLUTION: The vehicle controller has a starter motor 1 and a horizontal engine 2 in a driving system, and includes a high-voltage battery 21, a capacitor 23, and a hybrid control module 81 that controls recharging of the capacitor 23 using electric power of the high-voltage battery 21. In the FF plug-in hybrid vehicle controller, a hybrid control module 81 that performs starter starting control and recharging control lowers a recharging speed to the capacitor 23 more as a capacitor temperature is higher when recharging for raising a capacitor voltage to a starter starting permit voltage 'a' after starter starting.

Description

  The present invention relates to a vehicle control device that includes a capacitor that is a power source of a starter motor and controls recharging of the capacitor using electric power of a vehicle-mounted battery.

  Conventionally, when the vehicle is not in use, the voltage of the power storage unit is always controlled to be between the predetermined lower limit voltage and the predetermined holding voltage, and if the vehicle recognizes the driver by the driver authentication means, the power storage unit is fully charged. A power storage device having a configuration is known (see, for example, Patent Document 1).

JP 2008-141855 A

  However, the conventional device is configured to fully charge the power storage unit when the driver is recognized. For this reason, when the amount of charge decreases after the starter is started, if the power storage unit is recharged using a current that can be fully charged even though the power storage unit is hot, There is a problem that the temperature of the power storage unit rises due to the heat generated by recharging, and the deterioration of the power storage unit proceeds.

  The present invention has been made paying attention to the above problem, and an object of the present invention is to provide a vehicle control device capable of extending the capacitor life while shortening the starter start waiting time.

In order to achieve the above object, the present invention has a starter motor and an engine in a drive system. The power supply system includes an in-vehicle battery, a capacitor that is a power source of the starter motor, and a capacitor recharge control unit that controls recharging of the capacitor using electric power of the in-vehicle battery.
In this vehicle control device, an engine start control means for starting the starter by cranking the engine by using a starter motor using the capacitor as a power source, and a capacitor temperature detection means for detecting the temperature of the capacitor are provided.
When the capacitor recharge control means performs the recharge to increase the capacitor voltage to a voltage at which the starter can be started after the starter is started, the higher the capacitor temperature, the slower the recharge rate to the capacitor.

Therefore, after the starter is started, when recharging is performed to increase the capacitor voltage to a voltage at which the starter can be started, in the capacitor recharging control unit, the higher the capacitor temperature, the slower the recharging speed of the capacitor.
In other words, when performing recharging to increase the capacitor voltage to a voltage at which starter start is possible, it is necessary to recharge with a large current in order to shorten the waiting time until the next starter start is enabled. However, when the capacitor temperature is high, if the capacitor is recharged with a large current, deterioration of the capacitor due to heat generation proceeds.
On the other hand, the higher the capacitor temperature, the slower the recharge rate to the capacitor. When the capacitor temperature is low, the waiting time until starter start is shortened. Progress is suppressed.
As a result, it is possible to extend the capacitor life while shortening the starter start waiting time.

1 is an overall system diagram illustrating an FF plug-in hybrid vehicle to which a control device according to a first embodiment is applied. It is a power supply circuit diagram which shows the power supply system structure centering on the starter power supply of FF plug-in hybrid vehicle to which the control apparatus of Example 1 was applied. It is a block diagram which shows the control system structure of FF plug-in hybrid vehicle to which the control apparatus of Example 1 was applied. It is a flowchart which shows the flow of the capacitor recharge control process performed in the hybrid control module of Example 1. FIG. It is a lifetime determination factor relationship diagram which shows the relationship of the deterioration factor (voltage, temperature) which determines a capacitor lifetime.

  Hereinafter, the best mode for realizing a vehicle control apparatus of the present invention will be described based on a first embodiment shown in the drawings.

First, the configuration will be described.
The configuration of the FF plug-in hybrid vehicle (an example of a vehicle) to which the control device of the first embodiment is applied includes “drive system configuration”, “power supply system configuration”, “control system configuration”, and “detailed configuration of capacitor recharge control”. It is divided and explained.

[Drive system configuration]
FIG. 1 shows the entire FF plug-in hybrid vehicle. Hereinafter, the drive system configuration of the FF plug-in hybrid vehicle will be described with reference to FIG.

  As shown in FIG. 1, the drive system includes a starter motor 1 (abbreviated as “M”), a horizontal engine 2 (abbreviated as “ICE”), a first clutch 3 (abbreviated as “CL1”), and a motor / generator. 4 (abbreviation “M / G”), a second clutch 5 (abbreviation “CL2”), and a belt type continuously variable transmission 6 (abbreviation “CVT”). The output shaft of the belt type continuously variable transmission 6 is drivingly connected to the left and right front wheels 10R and 10L via a final reduction gear train 7, a differential gear 8, and left and right drive shafts 9R and 9L. The left and right rear wheels 11R and 11L are driven wheels.

  The starter motor 1 is a cranking motor that has a gear that meshes with an engine starting gear provided on a crankshaft of the horizontally placed engine 2 and that uses a capacitor 23 (described later) as a power source to rotationally drive the crankshaft when the engine is started.

  The horizontal engine 2 is an engine disposed in the front room with the crankshaft direction as the vehicle width direction, and includes an electric water pump 12 and a crankshaft rotation sensor 13 that detects reverse rotation of the horizontal engine 2.

  The first clutch 3 is a hydraulic multi-plate friction clutch that is interposed between the horizontally mounted engine 2 and the motor / generator 4, and is fully engaged / slip engaged / released by the first clutch oil pressure. The

  The motor / generator 4 is a three-phase AC permanent magnet type synchronous motor connected to the transverse engine 2 through a first clutch 3. The motor / generator 4 uses a high-power battery 21 described later as a power source, and an inverter 26 that converts direct current into three-phase alternating current during power running and converts three-phase alternating current into direct current during regeneration is connected to the stator coil. Connected through.

  The second clutch 5 is a wet-type multi-plate friction clutch by hydraulic operation that is interposed between the motor / generator 4 and the left and right front wheels 10R and 10L that are driving wheels. Slip fastening / release is controlled. The second clutch 5 of the first embodiment uses the forward clutch 5a and the reverse brake 5b provided in the forward / reverse switching mechanism of the belt-type continuously variable transmission 6 using planetary gears. That is, the forward clutch 5 a is the second clutch 5 during forward travel, and the reverse brake 5 b is the second clutch 5 during reverse travel.

  The belt-type continuously variable transmission 6 is a transmission that obtains a continuously variable transmission ratio by changing the belt winding diameter by the transmission hydraulic pressure to the primary oil chamber and the secondary oil chamber. The belt-type continuously variable transmission 6 includes a main oil pump 14 (mechanical drive), a sub-oil pump 15 (motor drive), and a first pressure using a line pressure generated by adjusting pump discharge pressure as a primary pressure. A control valve unit (not shown) for generating the second clutch hydraulic pressure and the transmission hydraulic pressure.

  The first clutch 3, the motor / generator 4 and the second clutch 5 constitute a one-motor / two-clutch drive system, and there are “EV mode” and “HEV mode” as main drive modes by this drive system. The “EV mode” is an electric vehicle mode in which the first clutch 3 is disengaged and the second clutch 5 is engaged and only the motor / generator 4 is used as a drive source. Driving in the “EV mode” is referred to as “EV driving”. . The “HEV mode” is a hybrid vehicle mode in which both the clutches 3 and 5 are engaged and the horizontal engine 2 and the motor / generator 4 are used as driving sources, and traveling in the “HEV mode” is referred to as “HEV traveling”.

  The motor / generator 4 basically includes a regenerative cooperative brake unit 16 that controls the total braking torque when the brake is operated in accordance with the regenerative operation when the brake is operated. The regenerative cooperative brake unit 16 includes a brake pedal, an electric booster, and a master cylinder, and the electric booster shares a hydraulic braking force by subtracting the regenerative braking force from the required braking force that appears in the pedal operation amount when the brake is operated. In this way, cooperative control for regenerative / hydraulic pressure is performed.

[Power system configuration]
FIG. 1 shows an entire system of an FF plug-in hybrid vehicle, and FIG. 2 shows a power supply system configuration centering on a starter power supply. Hereinafter, based on FIG.1 and FIG.2, the power supply system structure of FF plug-in hybrid vehicle is demonstrated.

  As shown in FIG. 1, the power supply system includes a high-power battery 21 (vehicle battery) as a motor / generator power supply, a 12V battery 22 as a 12V system load power supply, and a capacitor 23 as a starter power supply. Yes.

  The high-power battery 21 is a secondary battery mounted as a power source for the motor / generator 4. For example, a lithium ion battery in which a cell module in which a large number of cells are stacked is set in a battery pack case is used. The high-power battery 21 has a built-in junction box in which relay circuits for supplying / cutting off / distributing high-power are integrated, and further includes a battery temperature adjustment unit 24 having an air conditioner function, a battery charge capacity (battery SOC) and a battery. And a lithium battery controller 86 for monitoring the temperature.

  The high-power battery 21 and the motor / generator 4 are connected via a DC harness 25, an inverter 26, and an AC harness 27. The inverter 26 has a built-in junction box 28 in which relay circuits for supplying / cutting off / distributing strong power are integrated, and further includes a heating circuit 29, an electric air conditioner 30, and a motor controller 83 for performing power running / regenerative control. It is attached. That is, the inverter 26 converts a direct current from the DC harness 25 into a three-phase alternating current to the AC harness 27 during power running for driving the motor / generator 4 by discharging the high-power battery 21. Further, the three-phase alternating current from the AC harness 27 is converted into a direct current to the DC harness 25 during regeneration in which the high-power battery 21 is charged by power generation by the motor / generator 4.

  A rapid charging port 32 is connected to the high-power battery 21 via a DC harness 31, and a normal charging port 35 is connected via a DC branch harness 25 ′, a charger 33, and an AC harness 34. The charger 33 performs AC / DC conversion and voltage conversion. At the time of quick charging, for example, a connector plug of a charging stand installed outside the office is connected to the quick charging port 32 to be externally charged (plug-in quick charging). During normal charging, for example, a connector plug from a household power source is connected to the normal charging port 35 to be externally charged (plug-in normal charging).

  The 12V battery 22 is a secondary battery mounted as a power source for a 12V system load 36, which is another auxiliary machine except the starter motor 1, for example, a lead battery generally mounted in an engine vehicle or the like. Is used. The high voltage battery 21 and the 12V battery 22 are connected via a DC branch harness 25 ″, a DC / DC converter 37, and a battery harness 38. The DC / DC converter 37 changes the voltage of several hundred volts from the high voltage battery 21 to 12V. The DC / DC converter 37 is controlled by the hybrid control module 81 to manage the charge amount of the 12V battery 22.

  The capacitor 23 is a power storage device mounted as a dedicated power source for the starter motor 1 and has a large electrostatic capacity and has an excellent rapid charging / discharging performance (eDLC: electric Double Layer Capacitor). What is called is used. As shown in FIG. 2, the auxiliary load power supply system 39 and the capacitor 23 are connected via a battery branch harness 38 ′ provided with a fuse 40 and a capacitor charging circuit 41. The capacitor 23 and the starter motor 1 are connected via a capacitor harness 42, a resistor 43, and a relay switch 44. The capacitor 23 and the capacitor charging circuit 41 constitute a DLC unit 45, and the starter motor 1 and the relay switch 44 constitute a starter unit 46. Hereinafter, detailed configurations of the DLC unit 45 and the starter unit 46 will be described.

  As shown in FIG. 2, the DLC unit 45 includes a capacitor 23, a capacitor charging circuit 41, a spontaneous discharge switch 47, a forced discharge switch 48, a cell voltage monitor 49, and a capacitor temperature sensor 50 (capacitor temperature). Detecting means).

  The capacitor 23 is configured by connecting a plurality of DLC cells in series / parallel. The spontaneous discharge switch 47, the forced discharge switch 48, and the capacitor temperature sensor 50 are provided at both ends of the plurality of DLC cells. Provided in parallel. The cell voltage monitor 49 is provided in parallel to each DLC cell so as to detect the cell voltage (= capacitor capacity) of each of the plurality of DLC cells.

  The capacitor charging circuit 41 is constituted by a DC / DC converter circuit (a combination circuit of a switching element, a choke coil, a capacitor and a diode) with a built-in semiconductor relay by a switching method. The capacitor charging circuit 41 includes a semiconductor relay 51 and a DC / DC converter 52 that are controlled by a hybrid control module 81. The semiconductor relay 51 is a non-contact relay using a semiconductor switching element. For example, as schematically shown in the lower left part of FIG. 2, a light called a photocoupler that transmits an isolated input / output space with a light signal. The configuration uses a semiconductor. The semiconductor relay 51 has a switch function for disconnecting or connecting the capacitor 23 from the auxiliary load power supply system 38. The DC / DC converter 52 has a function of converting 12V direct current to 13.5V direct current and a function of switching capacitor charging current.

  The starter unit 46 includes a starter motor 1, a relay switch 43, an electromagnetic actuator 53, and a pinion shift mechanism 54.

  The electromagnetic actuator 53 turns on the relay switch 44 and shifts the pinion 57 of the pinion shift mechanism 54 to a position where it meshes with the ring gear 58 by electromagnetic force generated by energizing the two coils 55 and 56. When the energization is cut off, the relay switch 44 is turned off and the pinion 57 is shifted to a position where the engagement with the ring gear 58 is released. The ring gear 58 is provided on the crankshaft of the horizontal engine 2. The auxiliary load power supply system 39 and the two coils 55 and 56 are connected via a battery branch harness 38 ″ provided with a starter cut-off relay 59, a HEV / IS / relay 60, and a starter relay 61. Energization / cutoff of the off relay 59 is performed by a body control module 87. Energization / cutoff of the HEV / IS / relay 60 is performed by a hybrid control module 81. Energization / cutoff of the starter relay 61 is performed by an underhood switching module. The voltage sensor 62 for relay diagnosis is provided at a position where the battery branch harness 38 "intersects.

  The pinion shift mechanism 54 has a pinion 57 provided so as to be movable in the axial direction with respect to the motor shaft of the starter motor 1, one end connected to the electromagnetic actuator 53, and the other end fitted into the shift groove of the pinion 57. Shift lever 63.

[Control system configuration]
1 shows an overall system of an FF plug-in hybrid vehicle, FIG. 2 shows a power supply system configuration centering on a starter power supply, and FIG. 3 shows a control system configuration. Hereinafter, the control system configuration of the FF plug-in hybrid vehicle will be described with reference to FIGS.

  As shown in FIGS. 1 to 3, the control system includes a hybrid control module 81 (abbreviation: “HCM”) as an integrated control unit having a function of appropriately managing the energy consumption of the entire vehicle. Control means connected to the hybrid control module 81 include an engine control module 82 (abbreviation: “ECM”), a motor controller 83 (abbreviation: “MC”), and a CVT control unit 84 (abbreviation: “CVTCU”). Have. The data communication module 85 (abbreviation: “DCM”) and the lithium battery controller 86 (abbreviation: “LBC”) are included. Furthermore, it has a body control module 87 (abbreviation: “BCM”) and an underhood switching module 88 (abbreviation: “USM”). These control means include CAN communication line 90 (CAN is an abbreviation for “Controller Area Network”) except for a LIN communication line 89 (LIN: abbreviation for “Local Interconnect Network”) that connects hybrid control module 81 and DLC unit 45. Is connected so that bidirectional information can be exchanged.

  The hybrid control module 81 performs various controls based on input information from each control means, an ignition switch 91, an accelerator opening sensor 92, a vehicle speed sensor 93, and the like. Among these, the control performed for the purpose of driving the FF plug-in hybrid vehicle capable of external charging with high fuel efficiency is a travel mode based on the battery SOC of the high-power battery 21 (“CD mode”, “CS mode”). Selection control.

  The “CD mode (Charge Depleting mode)” is a mode in which priority is given to EV travel that consumes the power of the high-power battery 21 in principle. For example, while the battery SOC of the high-power battery 21 decreases from full SOC to set SOC. Is selected. However, HEV traveling is exceptionally performed in high-load traveling where driving force is insufficient in EV traveling. The start of the horizontal engine 2 during the selection of the “CD mode” is based on the start by the starter motor 1 (starter start), with the exception of the start by the motor / generator 4 (M / G start).

  The “CS mode (Charge Sustain mode)” is a mode in which priority is given to HEV running that maintains the power of the high-power battery 21 in principle, and is selected when the battery SOC of the high-power battery 21 is equal to or lower than the set SOC. That is, when it is necessary to maintain the battery SOC of the high-power battery 21 within a predetermined range, HEV traveling is performed by engine power generation that causes the motor / generator 4 to generate electric power by driving the lateral engine 2. The start of the horizontal engine 2 during the selection of the “CS mode” is based on the start by the motor / generator 4 (M / G start), with the exception of the start by the starter motor 1 (starter start). It should be noted that the “set SOC” that is the mode switching threshold value has hysteresis between the value when the CD mode → CS mode and the value when the CS mode → CD mode.

The hybrid control module 81 performs engine start control by the starter motor 1, charge control to the capacitor 23, and discharge control from the capacitor 23 in addition to the selection control of “CD mode” and “CS mode”. Furthermore, the following starter start related control is performed.
(A) Time-saving control from engine start to starter start permission.
(B) Time shortening control from ignition on to starter start permission.
(C) Deterioration progress suppression control of the capacitor 23.
(D) Control of countermeasures for high / low temperature of capacitor 23 (Example 1).
(E) Prevention of voltage sag of auxiliary equipment for vehicles.

  The engine control module 82 performs fuel injection control, ignition control, fuel cut control, and the like of the horizontal engine 2. The motor controller 83 performs power running control, regeneration control, and the like of the motor generator 4 by the inverter 26. The CVT control unit 84 performs engagement hydraulic pressure control of the first clutch 3, engagement hydraulic pressure control of the second clutch 5, shift hydraulic pressure control of the belt type continuously variable transmission 6, and the like. When the switch of the portable remote control key is remotely operated and the communication is established with the portable remote control key, the data communication module 85 controls, for example, lock / unlock of the charging port lid and the connector lock mechanism. The lithium battery controller 86 manages the battery SOC, battery temperature, and the like of the high-power battery 21. The body control module 87 performs energization / cutoff control of the starter cut-off relay 59. The under hood switching module 87 performs energization / cut-off control of the built-in starter relay 61 based on the range position signal from the inhibitor switch 94.

[Detailed configuration of capacitor recharge control]
FIG. 4 shows a capacitor recharge control process flow executed by the hybrid control module 81 (capacitor recharge control means). Hereinafter, each step of FIG. 4 showing a capacitor recharge control processing configuration will be described.

In step S1, it is determined whether or not the capacitor voltage detected by the cell voltage monitor 49 is equal to or higher than the starter start permission voltage a. If Yes (capacitor voltage ≧ starter start permission voltage a), the process proceeds to the end. If No (capacitor voltage <starter start permission voltage a), the process proceeds to step S2.
Here, for example, when the capacitor voltage at full charge is about 13.5 V, the “starter start permission voltage a” is set to a capacitor voltage of about 12.5 V that makes the required cranking time by starter start less than the target time. ing.

In step S2, following the determination that the capacitor voltage is less than the starter start permission voltage a in step S1, or the starter start prohibition in step S8, the capacitor temperature detected by the capacitor temperature sensor 50 is the deterioration warning threshold A. It is determined whether or not: If Yes (capacitor temperature ≦ degradation warning threshold A), the process proceeds to step S3. If No (capacitor temperature> degradation warning threshold A), the process proceeds to step S5.
Here, as the “deterioration warning threshold A”, for example, if the capacitor 23 is recharged from the charging current 1 (first charging current) set with an emphasis on shortening the starter start waiting time, the deterioration of the capacitor 23 Is set to a capacitor temperature (for example, 50 ° C. to 70 ° C.) that is predicted to soon exceed the deterioration threshold for proceeding. The deterioration threshold is a capacitor temperature at which the capacitor deterioration rapidly proceeds due to the thermal deterioration of the cells constituting the capacitor 23.

In step S3, following the determination that capacitor temperature ≦ deterioration warning threshold A in step S2 or the determination that capacitor voltage <starter start permission voltage a in step S4, charging current 1 (first charging Recharging is performed by (current), and the process proceeds to step S4.
Here, the “charging current 1” is a recharging current that places importance on shortening the waiting time until the start of the next starter when the capacitor is recharged. For example, the charging current 1 is 15A.

  In step S4, following the recharging with the charging current 1 in step S3, it is determined whether or not the capacitor voltage detected by the cell voltage monitor 49 is equal to or higher than the starter start permission voltage a. If Yes (capacitor voltage ≧ starter start permission voltage a), the process proceeds to the end. If No (capacitor voltage <starter start permission voltage a), the process returns to step S3.

In step S5, following the determination that capacitor temperature> degradation warning threshold A in step S2, a voltage difference (ab) obtained by subtracting the current voltage b from the starter start permission voltage a is calculated, and the voltage difference ( It is determined whether ab) is within a threshold value α. If Yes (voltage difference (ab) ≦ threshold α), the process proceeds to step S6. If No (voltage difference (ab)> threshold α), the process proceeds to step S8.
Here, as the “threshold value α”, for example, when recharging up to the starter start permission voltage a with the charging current 2 (second charging current), the voltage difference is such that the time required for recharging becomes the degradation limit time. It is set.

In step S6, following the determination that the voltage difference (ab) ≦ the threshold value α in step S5, or the determination that the capacitor voltage <the starter start permission voltage a in step S7, the recharge current is calculated. The charging current 1 (first charging current) is changed to a charging current 2 (second charging current) lower than the charging current 1, recharging is performed with the charging current 2, and the process proceeds to step S7.
Here, “charge current 2” is lower than charge current 1 (charging current 2 <charging current 1), which emphasizes shortening the starter start-up waiting time when recharging the capacitor, and importance is placed on suppressing the progress of capacitor deterioration. Set as a value. For example, when the charging current 1 is 15 A, the charging current 2 is set to 7 A.

  In step S7, following the recharging with the charging current 2 in step S6, it is determined whether or not the capacitor voltage detected by the cell voltage monitor 49 is equal to or higher than the starter start permission voltage a. If Yes (capacitor voltage ≧ starter start permission voltage a), the process proceeds to the end. If No (capacitor voltage <starter start permission voltage a), the process returns to step S6.

  In step S8, following the determination that voltage difference (ab)> threshold value α in step S5, starter start is prohibited, and the process returns to step S2.

Next, the operation will be described.
The operation of the control apparatus for the FF plug-in hybrid vehicle of the first embodiment will be described separately for [characteristic operation by capacitor power supply circuit configuration], [charge / discharge operation by capacitor power supply], and [capacitor recharge control operation].

[Characteristic effect of capacitor power circuit configuration]
For example, in an idle stop vehicle, when the starter motor power supply is a 12V battery, the power supply circuit configuration is a configuration in which the DLC unit 45 and the fuse 40 are removed from the capacitor power supply circuit configuration of the first embodiment. To do.

  In the case of this comparative example, the power supply of the starter motor and the vehicle auxiliary machines is shared by one 12V battery. For this reason, if the starter motor is used to start the engine when the required amount of power in the vehicle auxiliaries is high, the supply power is insufficient, and the voltage of the vehicle auxiliaries decreases suddenly at the moment of starting the engine. Low occurs.

  On the other hand, in the first embodiment, the auxiliary load power supply system 39 is configured by connecting the high-power battery 21 and the 12V battery 22 via the DC / DC converter 37. The DLC unit 45 includes a capacitor charging circuit 41 that is branched and connected from the DC / DC converter 37 and a capacitor 23 that is connected to the capacitor charging circuit 41. A capacitor power supply circuit is configured by providing a semiconductor relay 51 as a switch built in the capacitor charging circuit 41 between the auxiliary load power supply system 39 and the DLC unit 45.

  With this configuration, the 12V battery 22 and the capacitor 23 are charged with the electric power from the high-power battery 21, and the necessary power is supplied from the 12V battery 22 to the 12V system load 36, which is a vehicle auxiliary device. To supply the necessary power. That is, the starter motor 1 and the 12V system load 36 do not share the power source, and the two power sources including the 12V battery 22 and the capacitor 23 receive a charge backup by the high-power battery 21.

  And the capacitor power supply circuit is comprised by adding the DLC unit 45 (capacitor charging circuit 41 + capacitor 23), without changing the power supply circuit structure of the idle stop vehicle which is a comparative example. Thus, since the DLC unit 45 can be added in the same manner as the addition of auxiliary equipment, the control of the high-power battery 21 and the DC / DC converter 37 does not need to be changed from the control of the comparative example.

  Further, when the charge / discharge balance of the auxiliary load power supply system 39 is likely to be lost, the DLC unit 45 (capacitor charging circuit 41 + capacitor 23) can control the charging current and the auxiliary relay load by the semiconductor relay 51 as a switch. The power supply system 39 can be disconnected. For this reason, by opening the semiconductor relay 51 at the start of the starter, it is possible to prevent a voltage sag in which the voltage of the vehicle auxiliary machinery suddenly decreases. In addition, it is not necessary to change the converter capacity of the DC / DC converter 37 and the battery capacity of the 12V battery 22 from the converter capacity and battery capacity set in the comparative example.

[Charging / discharging action by capacitor power supply]
“Engine start control operation by starter motor 1”, “charge control operation to capacitor 23”, and “discharge control operation from capacitor 23” performed by hybrid control module 81 on the capacitor power supply circuit will be described.

The engine start by the starter motor 1 is based on the output of the starter start command from the hybrid control module 81. When the HEV / IS / relay 60 is energized, the relay switch 44 is turned on and the pinion 57 is shifted to a position where it engages with the ring gear 58. To do. As a result, the starter motor 1 using the capacitor 23 as a power source rotates the crankshaft of the horizontal engine 2 to start the starter, and the HEV / IS / relay 60 is cut off after a predetermined time from energization. The starter cut-off relay 59 is energized by the body control module 87 except when a vehicle condition prohibiting engine start is satisfied. Further, the starter relay 61 built in the underhood switching module 88 is energized only when the P range is selected, and is in a cut-off state when a D range other than the P range is selected.
Therefore, in principle, the engine start control by the starter motor 1 is performed by using the power of the capacitor 23 while the HEV / IS / relay 60 is energized by the starter start command under the starter start permission condition. Then, the horizontal engine 2 is started.

For charging the capacitor 23, the semiconductor relay 51 of the capacitor charging circuit 41 is closed based on the output of the charging command from the hybrid control module 81, and the capacitor charging current is selected. Thereby, the electric power from the high-power battery 21 is introduced into the capacitor 23 through the DC / DC converter 37 → the fuse 40 → the semiconductor relay 51 → the DC / DC converter 52, so that the short-time charging according to the capacitor charging current can be performed. Done. The capacitor charging current has a charging current 1 (for example, 15 A) as a basic current, and has a current 2 (for example, 7 A) that can be selected by changing from the current 1 as an exception.
Therefore, the charging control to the capacitor 23 uses the power from the high-power battery 21 and charges the capacitor 23 with the selected capacitor charging current while the charging command is output.

Based on the output of the natural discharge command from the hybrid control module 81, the discharge from the capacitor 23 causes the natural discharge from the capacitor 23 by closing the natural discharge switch 47 of the DLC unit 45. Further, the forced discharge from the capacitor 23 is performed by closing the forced discharge switch 48 of the DLC unit 45 based on the output of the forced discharge command from the hybrid control module 81. In the case of this forced discharge, the discharge amount per unit time is set larger than that in the case of natural discharge.
Therefore, the natural discharge control to the capacitor 23 is performed by converting the electric power of the capacitor 23 into resistance heat while the natural discharge switch 47 is closed based on the natural discharge command. In the forced discharge control to the capacitor 23, while the forced discharge switch 48 is closed based on the forced discharge command, the power of the capacitor 23 is converted into resistance heat, and discharge is performed in a shorter time than natural discharge.

[Capacitor recharge control action]
Factors that determine the capacitor lifetime include the capacitor voltage and the capacitor temperature, as shown in FIG. The capacitor voltage is determined by the state of charge depending on the charge / discharge frequency and output frequency (load pattern). For example, an increase in internal resistance due to maintaining full charge and voltage deterioration due to repeated charge / discharge are factors that shorten the capacitor life. The capacitor temperature is determined by the internal self-heating due to the starter start interval (load pattern) and the temperature state due to the operating ambient temperature. For example, thermal degradation due to cell temperature rise due to heat generation due to recharging with a large current shortens the capacitor life. It becomes a factor.

  That is, after the starter is started, when the capacitor voltage falls below the starter start permission voltage a, the capacitor 23 is recharged in preparation for the next star start. At this time, if the capacitor 23 is recharged with a large current in spite of the high capacitor temperature, the lifetime of the capacitor is shortened due to thermal degradation. Hereinafter, based on FIG. 4, a description will be given of the capacitor recharge control operation of the first embodiment performed by reflecting this.

  First, when the capacitor voltage is less than the starter start permission voltage a and the capacitor temperature is equal to or lower than the deterioration warning threshold A, the process proceeds to step S1, step S2, step S3, and step S4 in the flowchart of FIG. While it is determined in step S4 that the capacitor voltage is less than the starter start permission voltage a, the flow from step S3 to step S4 is repeated, and recharging is performed by the charging current 1 (for example, 15 A). Done. Further, when it is determined in step S4 that the capacitor voltage has become equal to or higher than the starter start permission voltage a, the process proceeds from step S4 to the end. That is, when the capacitor temperature is equal to or lower than the deterioration warning threshold value A, recharging is performed with the charging current 1 that places importance on shortening the waiting time until the start of the next starter start.

  On the other hand, when the capacitor voltage is less than the starter start permission voltage a, the capacitor temperature exceeds the deterioration warning threshold value A, and the voltage difference (ab) is within the threshold value α, step S1 → step in the flowchart of FIG. It progresses to S2-> step S5-> step S6-> step S7. While it is determined in step S7 that the capacitor voltage is less than the starter start permission voltage a, the flow from step S6 to step S7 is repeated, and recharging is performed by the charging current 2 (for example, 7A). Done. Further, when it is determined in step S7 that the capacitor voltage has become equal to or higher than the starter start permission voltage a, the process proceeds from step S7 to the end. That is, when the capacitor temperature exceeds the deterioration warning threshold A, but the voltage difference (ab) is within the threshold α, by switching to the charging current 2 lower than the charging current 1 and performing recharging, Progress of deterioration of the capacitor 23 due to heat generation is suppressed.

  Furthermore, when the capacitor voltage is less than the starter start permission voltage a, the capacitor temperature exceeds the deterioration warning threshold value A, and the voltage difference (ab) exceeds the threshold value α, step S1 → step S2 in the flowchart of FIG. → Proceed to step S5 → step S8. In step S8, starter start is prohibited. That is, when the capacitor temperature exceeds the deterioration warning threshold A and the voltage difference (ab) exceeds the threshold α, the time required for recharging is obtained by switching to the charging current 2 and performing recharging. As a result, the heat generation of the capacitor 23 cannot be avoided. Therefore, in such a case, starter start is prohibited, and in the flowchart of FIG. 4, step S8 → step S2 → step S5 is repeated, and by waiting for the capacitor temperature to drop until the temperature condition of step S2 is satisfied, 23 to suppress the progress of deterioration.

As described above, in the first embodiment, after the starter is started, when recharging is performed to increase the capacitor voltage to a voltage at which the starter can be started, the recharge rate to the capacitor 23 is decreased as the capacitor temperature is higher. doing.
That is, when performing recharging to increase the capacitor voltage to a starter start permission voltage a that allows starter start, it is necessary to recharge with a large current in order to shorten the waiting time until the next starter start is enabled. is there. However, when the capacitor temperature is high, recharging with a large current causes deterioration of the capacitor 23 due to heat generation as described in the factor determining the capacitor life.
On the other hand, the higher the capacitor temperature, the slower the recharge rate of the capacitor 23, so that when the capacitor temperature is low, the waiting time until starter start is shortened, and when the capacitor temperature is high, the heat generation of the capacitor 23 occurs. Progress of deterioration due to is suppressed.
As a result, it is possible to extend the capacitor life while shortening the starter start waiting time.

In the first embodiment, after the starter is started, when the capacitor voltage is equal to or lower than the starter start permission voltage a and the capacitor temperature is equal to or lower than the deterioration warning threshold A, the charging current 1 set with an emphasis on shortening the starter start waiting time is set. Is used to recharge the capacitor up to the starter start permission voltage a. When the capacitor temperature exceeds the deterioration warning threshold A, the capacitor is recharged up to the starter start permission voltage a using the charging current 2 that is lower than the charging current 1 and that is set with emphasis on suppression of the progress of capacitor deterioration. The structure which performs is adopted.
In other words, by using the capacitor temperature deterioration warning threshold A, recharge control is performed with emphasis on shortening the waiting time in the capacitor temperature region below the deterioration warning threshold A. In the capacitor temperature range exceeding the deterioration warning threshold A, recharge control is performed with emphasis on suppression of deterioration progress. In this way, the recharge control can be divided into two.
Therefore, the simple switching control using the capacitor temperature deterioration warning threshold value A can achieve both reduction of the starter start waiting time and extension of the capacitor life.

In the first embodiment, after the starter is started, when the capacitor voltage is equal to or lower than the starter start permission voltage a and the capacitor temperature exceeds the deterioration warning threshold A, the voltage difference between the starter start permission voltage a and the current voltage b ( A configuration is adopted in which the recharge speed of the capacitor 23 is decreased as a-b) increases.
That is, the factor that shortens the capacitor life depending on the temperature greatly affects not only the capacitor temperature at the start of recharging, but also the amount of heat generated by the time required for recharging after the start of recharging. At this time, the voltage difference (ab) between the starter start permission voltage a and the current voltage b is a value representing the size of the recharge capacity, in other words, the recharge required time.
Therefore, when the capacitor temperature is high, the recharge speed of the capacitor 23 is decreased as the voltage difference (ab) is increased, so that the life of the capacitor can be extended regardless of the recharge required time.

In the first embodiment, it is determined whether or not the voltage difference (ab) between the starter start permission voltage a and the current voltage b is within the threshold value α, and the voltage difference (ab) is within the threshold value α. The capacitor 23 is recharged using a charging current 2 lower than the charging current 1. And the structure which prohibits a starter start is employ | adopted when the voltage difference (ab) exceeds the threshold value (alpha).
In other words, when the voltage difference (ab) exceeds the threshold value α, the capacitor temperature may rise until the capacitor temperature exceeds the deterioration threshold even if the recharge power is kept small. In such a case, the starter start is prohibited without recharging the capacitor 23. Then, by waiting for the capacitor temperature to drop, the progress of deterioration of the capacitor 23 can be suppressed.
Therefore, when the voltage difference (a−b) exceeds the threshold value α, starter start-up is prohibited, and the capacitor life can be extended by waiting for the capacitor temperature to drop.

Next, the effect will be described.
In the control device for the FF plug-in hybrid vehicle of the first embodiment, the effects listed below can be obtained.

(1) The drive system has a starter motor 1 and an engine (horizontal engine 2).
As a power supply system, an on-board battery (high-power battery 21), a capacitor 23 that is a power source of the starter motor 1, and a capacitor recharge that controls recharging of the capacitor 23 using the power of the on-board battery (high-power battery 21). In a control device for a vehicle (FF plug-in hybrid vehicle) comprising control means (hybrid control module 81),
Engine start control means (hybrid control module 81) that starts the starter by cranking the engine (horizontal engine 2) using the starter motor 1 that uses the capacitor 23 as a power source;
Capacitor temperature detecting means (capacitor temperature sensor 50) for detecting the temperature of the capacitor 23, and
When the capacitor recharge control means (hybrid control module 81) performs recharge to increase the capacitor voltage to a voltage at which the starter can be started (starter start permission voltage a) after starting the starter, the higher the capacitor temperature, the higher the capacitor 23 is slowed down (FIG. 4).
For this reason, it is possible to extend the life of the capacitor while reducing the waiting time for starting the starter.

(2) After the starter is started, the capacitor recharge control means (hybrid control module 81) waits for starter start when the capacitor voltage is not more than the starter start permission voltage a and the capacitor temperature is not more than the deterioration warning threshold A. When the capacitor is recharged to the starter start permission voltage a using the first charging current (charging current 1) set with emphasis on time reduction, and the capacitor temperature exceeds the deterioration warning threshold A, the first Capacitor recharging up to the starter start permission voltage a is performed using a second charging current (charging current 2) that is lower than the charging current (charging current 1) and is set with emphasis on suppression of capacitor deterioration progression (FIG. 4). ).
For this reason, in addition to the effect of (1), both the shortening of the starter start waiting time and the extension of the capacitor life can be achieved by simple switching control using the capacitor temperature deterioration warning threshold A. In addition, since the capacitor is recharged up to the starter start permission voltage a, it is possible to suppress deterioration of the capacitor 23 (extend the capacitor life) as compared with the recharge up to full charge.

(3) After the starter is started, the capacitor recharge control means (hybrid control module 81) starts the starter when the capacitor voltage is equal to or lower than the starter start permission voltage a and the capacitor temperature exceeds the deterioration warning threshold A. The larger the voltage difference (ab) between the permitted voltage a and the current voltage b is, the slower the recharging speed of the capacitor 23 is (FIG. 4).
For this reason, in addition to the effect of (2), when the capacitor temperature is high, the life of the capacitor can be extended regardless of the time required for recharging.

(4) The capacitor recharge control means (hybrid control module 81) determines whether or not a voltage difference (ab) between the starter start permission voltage a and the current voltage b is within a threshold value α, When the voltage difference (ab) is within a threshold value α, the capacitor 23 is recharged using a second charging current (charging current 2) lower than the first charging current (charging current 1), and the voltage When the difference (ab) exceeds the threshold value α, starter start is prohibited (FIG. 4).
For this reason, in addition to the effect of (3), when the voltage difference (ab) exceeds the threshold value α, starter start-up is prohibited and the capacitor life can be extended by waiting for the capacitor temperature to drop. .

  As mentioned above, although the vehicle control apparatus of the present invention has been described based on the first embodiment, the specific configuration is not limited to the first embodiment, and the invention according to each claim of the claims. Design changes and additions are allowed without departing from the gist.

  In the first embodiment, as the capacitor recharge control means, after the starter is started, when the capacitor voltage is equal to or lower than the starter start permission voltage a and the capacitor temperature is equal to or lower than the deterioration warning threshold A, the starter start permission is performed using the charging current 1. In the example, the capacitor is recharged up to the voltage a, and the capacitor is recharged up to the starter start permission voltage a using the charging current 2 when the capacitor temperature exceeds the deterioration warning threshold A. However, as the capacitor recharge control means, when the recharge is performed to increase the capacitor voltage to a voltage at which the starter can be started after the starter is started, the recharge rate to the capacitor is increased steplessly or in multiple steps as the capacitor temperature increases. It may be a thing that slows down. Furthermore, not only the capacitor recharge up to the starter start permission voltage, but also a recharge to the full charge may be used as long as the starter start voltage is possible.

  In the first embodiment, as the capacitor recharge control means, it is determined whether or not the voltage difference (ab) between the starter start permission voltage a and the current voltage b is within the threshold value α, and the voltage difference (ab) ) Is within the threshold value α, the charging current 2 is used to recharge the capacitor 23, and when the voltage difference (ab) exceeds the threshold value α, the starter start is prohibited. However, the capacitor recharge control means may be an example in which, when the voltage difference (ab) is within the threshold value α, the charging current is decreased as the voltage difference (ab) is larger.

  In the first embodiment, as an example of the capacitor recharge control unit, recharge or starter start permission control is performed using capacitor voltage information. However, the capacitor recharge control means may be an example of performing recharge or starter start permission control using capacitor capacity information instead of capacitor voltage information. That is, when the capacitor capacity is Q, the capacitance is C, and the capacitor voltage is V, Q = C · V. When the capacitance C is constant, the capacitor capacity Q is proportional to the capacitor voltage V. Thus, even if capacitor capacity information is used instead of capacitor voltage information, equivalent control is achieved.

  In Example 1, the example which uses the hybrid control module 81 as a capacitor recharge control means was shown. However, as the capacitor recharge control means, an independently provided power supply system controller may be used, or an example in which a power supply system control unit is provided in a controller other than the hybrid control module may be used.

  In Example 1, the example which applies the control apparatus of this invention to FF plug-in hybrid vehicle was shown. However, the control device of the present invention can also be applied to a hybrid vehicle that does not have an external charging function. Further, the present invention can be applied not only to FF hybrid vehicles but also to FR hybrid vehicles and 4WD hybrid vehicles. In addition, the present invention can be applied to an engine vehicle that performs idle stop control for stopping the engine when the vehicle is stopped by using a 12V battery as a vehicle-mounted battery. In short, any vehicle including an in-vehicle battery that is a recharging power source for a capacitor and a capacitor that is a power source for a starter motor can be applied.

1 Starter motor 2 Horizontal engine (engine)
3 First clutch 4 Motor / generator 5 Second clutch 6 Belt-type continuously variable transmissions 10R, 10L Left and right front wheels 11R, 11L Left and right rear wheels 21 High-power battery (vehicle battery)
22 12V battery 23 capacitor 37 DC / DC converter 41 capacitor charging circuit 45 DLC unit 49 cell voltage monitor 50 capacitor temperature sensor (capacitor temperature detection means)
51 Semiconductor Relay 52 DC / DC Converter 81 Hybrid Control Module (Capacitor Recharge Control Unit, Engine Start Control Unit)

Claims (4)

It has a starter motor and an engine in the drive system,
In a vehicle control apparatus comprising: an in-vehicle battery, a capacitor that is a power source of the starter motor, and a capacitor recharge control unit that controls recharging of the capacitor using electric power of the in-vehicle battery as a power supply system;
Engine start control means for starting the starter by cranking the engine using a starter motor having the capacitor as a power source;
Capacitor temperature detecting means for detecting the temperature of the capacitor; and
When the capacitor recharge control means performs recharge to increase the capacitor voltage to a voltage at which starter start is possible after starter start, the capacitor recharge rate is reduced as the capacitor temperature increases. Vehicle control device. The vehicle control device according to claim 1,
The capacitor recharge control means is set to emphasize a reduction in starter start waiting time when the capacitor voltage is equal to or lower than the starter start permission voltage and the capacitor temperature is equal to or lower than the deterioration warning threshold after starter start. The capacitor is recharged up to the starter start permission voltage using the charging current, and when the capacitor temperature exceeds the deterioration warning threshold, it is lower than the first charging current and set with emphasis on suppression of capacitor deterioration progress Capacitor recharging up to the starter start permission voltage using the second charging current. A vehicle control device. The vehicle control device according to claim 2,
After the starter is started, the capacitor recharge control means has a voltage difference between the starter start permission voltage and the current voltage when the capacitor voltage is equal to or lower than the starter start permission voltage and the capacitor temperature exceeds the deterioration warning threshold. The vehicle control device is characterized in that the larger the value is, the slower the recharging speed of the capacitor is. In the vehicle control device according to claim 3,
The capacitor recharge control means determines whether or not a voltage difference between the starter start permission voltage and the current voltage is within a threshold value. When the voltage difference is within the threshold value, a first recharge current lower than the first charging current is determined. 2. The vehicle control device according to claim 1, wherein recharging of the capacitor is performed using two charging currents, and starter start is prohibited when the voltage difference exceeds a threshold value.