JP6451582B2 - Charge / discharge control device for power storage device - Google Patents

Description

  The present invention relates to a charge / discharge control device for a power storage device that limits charge / discharge power of a power storage device that supplies power to a vehicle driving motor via an energization member.

  A power storage device such as a battery mounted on a hybrid vehicle or the like supplies electric power to a vehicle driving motor, and is charged when the amount of stored power decreases. Current between the power storage device and the traveling motor flows through energized components such as relays, fuses, and harnesses. When a current flows through the power storage device, Joule heat is generated in these energized parts. If the temperature of the current-carrying component is excessively increased, the normal function may be impaired. Therefore, it is necessary to control charging / discharging of the power storage device from the viewpoint of appropriately protecting the current-carrying component.

  Therefore, based on the current value detected at the time of charge / discharge of the power storage device, an evaluation value for evaluating the temperature level of the energized component is calculated, and when this evaluation value exceeds the threshold value, the charge / discharge power of the power storage device is calculated. There has been proposed a control device that restricts (for example, Patent Document 1).

JP 2014-45541 A

  The invention described in Patent Literature 1 limits the charge / discharge power of the power storage device based on an evaluation value for evaluating the temperature level of the energized component. The evaluation value of the temperature level of the energized component is calculated based on the square value of the current, etc., but the energized component is affected by the environmental temperature, that is, the ambient temperature around the energized component. For this reason, the time during which the same current can be applied (energization possible time) differs between the low and high ambient temperatures, and the low rate of temperature rise even when the same current is applied in the low ambient temperature, resulting in a longer time. It can be energized.

  In particular, current-carrying parts such as relays, fuses, and harnesses may be arranged in the engine room, and in this case, they may be affected by heat when the engine is driven. For this reason, when evaluating the temperature level of the current-carrying parts, it is conceivable to use an ambient temperature (a state where the ambient temperature is high) based on the assumption that the engine is affected by heat.

  However, when the engine is stopped during leaving, external charging, EV driving, etc., the ambient temperature of the energized parts is low, and in this case, it is assumed that the engine is affected by the heat described above. If the ambient temperature (the atmosphere temperature is high) is used, even if the ambient temperature of the current-carrying part is actually not high, the same evaluation value as that in the state where the ambient temperature of the current-carrying part is high is calculated. Charge / discharge restriction intervenes at an early timing.

  Accordingly, an object of the present invention is to evaluate the temperature level of the energized component in consideration of the ambient temperature of the energized component, and to limit the charge / discharge power of the power storage device suitable for the ambient temperature of the energized component.

A charge / discharge control device for a power storage device according to the present invention includes a current-carrying component that conducts charging / discharging power between the power storage device and a vehicle driving motor, and that limits the charge / discharge power according to the temperature of the current-carrying component. A charge / discharge control device for an apparatus, wherein an atmosphere temperature determination unit that determines an ambient temperature of the energized component disposed in an engine room, a determination result of the atmosphere temperature determination unit, and a charge / discharge of the power storage device are detected. And an evaluation value calculation unit that calculates an evaluation value for evaluating the temperature level of the energized component based on the current value, and limits the charge / discharge power of the power storage device when the evaluation value exceeds a threshold value A power limiting unit, and the evaluation value calculation unit calculates the evaluation value to be small based on a decrease in the ambient temperature when the ambient temperature determination unit determines that the ambient temperature of the energized component has decreased. And The serial current value greatly calculates the evaluation value as large, characterized by.

  ADVANTAGE OF THE INVENTION According to this invention, the temperature of an electricity supply component can be evaluated in consideration of the atmospheric temperature of an electricity supply component, and the charge / discharge electric power of the electrical storage apparatus suitable for the atmosphere temperature of an electricity supply component can be performed. In particular, when it is determined that the ambient temperature of the current-carrying component has decreased, the evaluation value of the current-carrying component is calculated to be small, so the time until the evaluation value exceeds the threshold value becomes longer, and the charging / discharging power restriction start of the power storage device is started. The timing at which the charge / discharge restriction intervenes can be delayed by being delayed.

It is a schematic block diagram of the hybrid vehicle carrying an electrical storage apparatus. It is a schematic electric circuit diagram of a power storage device. It is a figure which shows a low temperature atmospheric temperature map and a high temperature atmospheric temperature map, and is a figure which shows the relationship between the electric current value according to the atmospheric temperature of electricity supply components, and its energization possible time. It is a figure which shows the relationship between the evaluation value F (N) based on a low temperature atmosphere temperature map and a high temperature atmosphere temperature map, and a restriction | limiting start threshold value, and the relationship between evaluation value F (N) and input-output restrictions. It is a flowchart which shows the restriction | limiting process of the charging / discharging electric power of an electrical storage apparatus. It is a flowchart which shows the switching process of an atmospheric temperature map. It is a timing chart which shows the change timing of an atmospheric temperature map based on the charge continuation time of external charge. It is a timing chart which shows the switching timing of an atmospheric temperature map based on the OFF continuation time of an ignition switch. It is a figure which shows the modification of atmospheric temperature map, and is a figure which shows low temperature atmospheric temperature map, middle temperature atmospheric temperature map, and high temperature atmospheric map temperature. It is a flowchart which shows the modification of the determination process of the atmospheric temperature state of an electricity supply component.

  A hybrid vehicle 100 as an embodiment of the present invention is a vehicle including a motor generator MG2 and an engine 20 as a power source for running the vehicle. As shown in FIGS. 1 and 2, the hybrid vehicle 100 includes an engine 20 that outputs power by burning fuel such as a gasoline engine or a diesel engine, a power split mechanism 21 to which an output shaft of the engine 20 is connected, Motor generator MG1 capable of generating electricity connected to power split device 21, motor generator MG2 mainly used for traveling connected to power split device 21, and DC power output from power storage device 1 is converted to AC power. And an inverter 22 that supplies the motor generators MG1 and MG2.

  Engine 20, power split mechanism 21, motor generators MG <b> 1, MG <b> 2, inverter 22, etc. are arranged in engine room 101 at the front of hybrid vehicle 100. The power storage device 1 is disposed at the rear of the hybrid vehicle 100, for example, at the lower part of the rear seat, the luggage compartment, or the lower part of the floor panel. The power storage device 1 and the inverter 22 are electrically connected by a power cable 12. In engine room 101, inverter 22 and motor generators MG1, MG2 are connected by power cable 13.

  The power storage device 1 is an assembled battery, and the assembled battery includes a plurality of unit cells 10 electrically connected in series. The number of unit cells 10 constituting the power storage device 1 can be appropriately set based on the required output of the power storage device 1 and the like. The power storage device 1 may include a plurality of single cells 10 that are electrically connected in parallel. As the unit cell 10, a secondary battery such as a nickel metal hydride battery or a lithium ion battery can be used. An electric double layer capacitor (capacitor) can be used instead of the secondary battery. Note that the power storage device 1 may be connected to the booster circuit, and the booster circuit may be connected to the inverter 22. By using the booster circuit, the output voltage of power storage device 1 can be boosted, and the output voltage from inverter 22 to power storage device 1 can be reduced.

  Inverter 22 converts the DC power output from power storage device 1 into AC power, and outputs the AC power to motor generator MG2. Motor generator MG2 is connected to drive shaft 26 connected to drive wheel 25 via transmission T / M, and the driving force of motor generator MG2 is transmitted to drive shaft 26 via transmission T / M. Is transmitted to the drive wheel 25. By transmitting the driving force of motor generator MG2 to driving wheel 25 via transmission TM, vehicle traveling (EV traveling) using the electric power of power storage device 1 can be performed.

  Power split device 21 transmits the power of engine 20 to drive wheel 25 (HV traveling) or to motor generator MG1. Motor generator MG1 receives power from engine 20 to generate power. Electric power generated by motor generator MG1 is supplied to motor generator MG2 or supplied to power storage device 1 via inverter 22. If the electric power generated by the motor generator MG1 is supplied to the motor generator MG2, the driving wheels 25 can be driven by the driving force of the motor generator MG2. If the electric power generated by motor generator MG1 is supplied to power storage device 1, power storage device 1 can be charged.

  Further, when hybrid vehicle 100 is decelerated or stopped, motor generator MG2 converts kinetic energy generated during braking of hybrid vehicle 100 into electrical energy (AC power). Inverter 22 converts AC power generated by motor generator MG2 into DC power, and outputs the DC power to power storage device 1. Thereby, the electrical storage apparatus 1 can store regenerative electric power.

  FIG. 2 is a schematic electric circuit diagram for charging and discharging the power storage device 1. As shown in FIG. 2, the power storage device 1 is connected to the inverter 22 via the positive electrode line PL and the negative electrode line NL. System main relays SMR-B and SMR-G are provided on the positive line PL and the negative line NL, respectively. A system main relay SMR-P and a current limiting resistor R are connected in parallel to the system main relay SMR-G, and the system main relay SMR-P and the current limiting resistor R are connected in series. System main relays SMR-B, SMRG-G, and SMR-P may be arranged in engine room 101 in consideration of maintainability. System main relays SMR-B, SMR-G, and SMR-P are controlled by an ECU (not shown) of hybrid vehicle 100.

  The ECU switches the system main relay SMR-B from off to on and switches the system main relay SMR-P from off to on based on the on signal of the ignition switch IG of the hybrid vehicle 100. Thereby, it can suppress that an electric current flows into the current limiting resistance R, and an inrush current flows. Next, after the system main relay SMR-G is switched from OFF to ON, the system main relay SMR-P is switched from ON to OFF. As a result, the electric power of power storage device 1 can be supplied to each electrical device including inverter 22 of hybrid vehicle 100.

  On the other hand, when the ignition switch IG is switched from on to off, the ECU switches the system main relays SMR-B and SMR-G from on to off. Thereby, connection between power storage device 1 and each electric device of hybrid vehicle 100 is interrupted.

  Here, the energization component electrically connected to the power storage device 1 will be described. The energization components in the present embodiment are components that energize charge / discharge power between the power storage device 1 and the motor generators MG1 and MG2, and include power cables 12 and 13 disposed in the engine room 101, and a system main relay SMR. -B, SMR-G, SMR-P, etc. correspond. Hereinafter, the power cable 12, the system main relays SMR-B, SMR-G, SMR-P and the like are collectively referred to as energized parts A.

  A charger 40 for supplying power to the power storage device 1 from an external power source 43 independent of the hybrid vehicle 100 can be connected to the positive electrode line PL and the negative electrode line NL of the power storage device 1. By using the charger 40, the power storage device 1 can be charged. Charger 40 is connected to power storage device 1 via charging relays Rch1 and Rch2. When charging relays Rch1 and Rch2 are on, power from external power supply 43 can be supplied to power storage device 1. Switching control between on and off of the charging relays Rch1 and Rch2 is performed by the controller 30 that controls charging / discharging of the power storage device 1.

  The charger 40 is connected to an inlet 41, and a charging plug 42 is connected to the inlet 41. The charging plug 42 is a connection connector provided on the charging cable P extending from the external power source 43. By connecting the charging plug 42 to the inlet 41, external power from the external power supply 43 can be supplied to the power storage device 1 via the charger 40.

  The external power source 43 is a power source provided outside the hybrid vehicle 100. The external power source 43 is, for example, a commercial power source. When external power supply 43 supplies AC power, charger 40 includes an AC / DC converter (not shown), converts AC power from external power supply 43 into DC power, and supplies DC power to power storage device 1. Charging the power storage device 1 by supplying the power from the external power source 43 to the power storage device 1 is called external charging. External charging is performed in a state where the ignition switch IG is off, that is, the engine 20 is stopped.

  The power storage device 1 is connected to a voltage monitoring unit 15 that detects the voltage of the power storage device 1, a current sensor 16 that detects a charge / discharge current flowing through the power storage device 1, and a temperature sensor 17 that detects the temperature of the power storage device 1. Yes. Voltage monitoring unit 15 outputs the detected voltage of power storage device 1 to controller 30. The current sensor 16 outputs the detected charge / discharge current flowing through the power storage device 1 to the controller 30. Temperature sensor 17 outputs the detected temperature of power storage device 1 to controller 30. Regarding the current value detected by the current sensor 16, the discharge current can be a positive value and the charging current can be a negative value. The current sensor 16 can also detect a charging current supplied from the external power supply 43 via the charger 40.

  The controller 30 is a charge / discharge control device that performs charge / discharge control of the power storage device 1. A controller area network (CAN) (not shown) constituting an in-vehicle network is connected to the controller 30, and the detected values of the voltage monitoring unit 15, current sensor 16, temperature sensor 17, and ignition switch IG are connected via this CAN. ON / OFF signal is input. Controller 30 calculates the SOC of power storage device 1 based on the detected values of voltage monitoring unit 15, current sensor 16, and temperature sensor 17.

  In the present embodiment, the controller 30 performs the following charge / discharge control. First, controller 30 calculates allowable input power (maximum value of power charged in power storage device 1) SWin and allowable output power (maximum value of power discharged from power storage device 1) SWout based on the calculated SOC. The charge / discharge power of the power storage device 1 is limited so as not to exceed the allowable input power SWin and the allowable output power SWout. Thereby, the overdischarge and overcharge of the electrical storage device 1 are prevented, and the electrical storage device 1 is protected.

  Further, when a current flows through the power storage device 1, a current also flows through the energized components A that are electrically connected to the power storage device 1, and Joule heat is generated in these energized components A. Therefore, if the temperature of the energized component A rises and exceeds the allowable temperature, the energized component A may not function normally. Therefore, based on the current value of the power storage device 1, an evaluation value F (N) related to the temperature level of these energized components A is calculated, and the allowable input is set so that the calculated evaluation value F (N) does not exceed the threshold value. The power SWin and the allowable output power SWout are limited to limit the charge / discharge power of the power storage device 1. Thereby, the temperature rise of the electricity supply component A is suppressed.

  Furthermore, the current-carrying component A is affected by the ambient temperature. For this reason, the time during which the same current can be applied (energization possible time) differs between the low and high ambient temperatures, and the low rate of temperature rise even when the same current is applied in the low ambient temperature, resulting in a longer time. It can be energized. In particular, when the energized component A is disposed in the engine room 101 as in the present embodiment, the ambient temperature of the energized component A becomes high when the engine 20 is driven. Further, since the engine 20 is in a stopped state when the hybrid vehicle 100 is left, during external charging, or during EV travel, the ambient temperature of the energized component A is lower than the ambient temperature when the engine 20 is driven. Therefore, the evaluation value F (N) is calculated in consideration of the ambient temperature of the energized component A, thereby limiting the charge / discharge power of the power storage device 1 suitable for the ambient temperature of the energized component A.

  In summary, the controller 30 limits the charge / discharge power of the power storage device 1 so as not to exceed the calculated allowable input power SWin and allowable output power SWout, and also considers the ambient temperature of the energized component A. An evaluation value F (N) related to the temperature level of the energized component A is calculated, and the allowable input power SWin and the allowable output power SWout are further limited based on the calculated evaluation value F (N).

  Next, details of the controller 30 will be described. The controller 30 is configured by hardware mainly including a digital circuit, and includes various control units for performing charge / discharge control of the power storage device 1. The controller 30 determines the ambient temperature of the energized component A arranged in the engine room 101 based on the driving state of the engine 20 and the evaluation value F according to the plurality of ambient temperatures of the energized component A. The ambient temperature characteristic storage unit 34 that stores a plurality of characteristics (maps) for calculating the annealing coefficient K used to calculate (N), the current value I of the power storage device 1, and the previous calculation. An evaluation value calculation unit 31 that calculates an evaluation value F (N) based on the evaluation value and an annealing coefficient K calculated according to the temperature change of the energized component A and the ambient temperature of the energized component A; The allowable input power SWin and the allowable output power SWout of 1 are changed based on the evaluation value F (N) calculated by the evaluation value calculation unit 31, and the charge power upper limit value Win and the discharge power upper limit value Wout after the change are changed. And a Win / Wout limiting unit 32 for limiting the charge and discharge power of the power storage device 1.

  The ambient temperature determination unit 33 determines whether the ambient temperature of the energized component A is high (high temperature) or low (low temperature). In particular, in the present embodiment, it is determined when the ambient temperature of the energized component A has changed from a high state to a low state, that is, when the ambient temperature has decreased.

  The ambient temperature determination unit 33 has a timer function for measuring time. Atmospheric temperature determination unit 33 measures an elapsed time from when ignition switch IG of hybrid vehicle 100 is turned off, and determines that hybrid vehicle 100 is in a neglected state when this measurement time exceeds a predetermined time. Thus, it is estimated that the temperature of the engine room 101 is sufficiently lowered (low temperature). The ambient temperature determination unit 33 determines that the ambient temperature of the energized component A is low based on the estimation result.

  In addition, when the ignition switch IG of the hybrid vehicle 100 is turned off, the elapsed time from the start of external charging is measured, and when this measured time exceeds a predetermined time, the hybrid vehicle 100 is externally It is determined that the battery is being charged, and in this case as well, it is estimated that the temperature of the engine room 101 is sufficiently lowered. The ambient temperature determination unit 33 determines that the ambient temperature of the energized component A is low based on the estimation result.

  The ambient temperature characteristic storage unit 34 includes a high temperature ambient temperature map Mh indicating characteristics when the ambient temperature of the energized component A is high, and a low temperature ambient temperature map Ml indicating characteristics when the ambient temperature of the energized component A is low. Is remembered.

  As shown in FIG. 3, the high temperature ambient temperature map Mh and the low temperature ambient temperature map Ml indicate the relationship between the current value according to the ambient temperature of the energized component A and the energizable time, and calculate the annealing coefficient K. It is a map. In FIG. 3, when the current value Ib flows through the current-carrying component A, the energizable time is T2 in the high temperature atmosphere, but in the low temperature atmosphere, the degree of temperature rise is low due to the current value Ib. Long T1. As described above, the time during which the same current can be applied (energization possible time) differs between the low temperature atmosphere and the high temperature atmosphere.

  For this reason, the annealing coefficient K used to calculate the evaluation value F (N) is calculated separately depending on the atmospheric temperature. In FIG. 3, a low temperature atmosphere temperature map Ml indicated by a solid line is a map for calculating the annealing coefficient Klow based on the low temperature atmosphere. A high temperature atmosphere temperature map Mh indicated by a one-dot chain line is a map for calculating an annealing coefficient Khigh based on an atmosphere (high temperature atmosphere) other than the low temperature atmosphere. The annealing coefficient Klow and the annealing coefficient Khigh are defined based on the current value and the energization possible time at the current value. The low temperature atmosphere temperature map Ml and the high temperature atmosphere temperature map Mh can be obtained in advance by experiments or the like by changing the atmosphere temperature.

  Evaluation value calculation unit 31 calculates evaluation value F (N) based on current value I of power storage device 1. The evaluation value F (N) is a value for evaluating the temperature level of the energized component A, that is, how much (level) the temperature of the energized component A is, and the evaluation value F (N) Based on this, the temperature state of the energized component A is determined. In addition, since the energized component A generates heat due to the energized current and is affected by heat due to the ambient temperature, it is necessary to calculate the evaluation value F (N) in consideration of these.

  Therefore, the evaluation value calculation unit 31 calculates the evaluation value F (N) using the smoothing coefficient K regarding the heat generation due to energization and the ambient temperature. Regarding the characteristic of the annealing coefficient K, with respect to the temperature of the energized component A, the higher the temperature, the larger the evaluation value F (N), and the lower the temperature, the smaller the evaluation value F (N). Further, regarding the characteristic of the annealing coefficient K, with respect to the ambient temperature of the energized component A, the evaluation value F (N) is increased as the ambient temperature is higher, and the evaluation value F (N) is decreased as the ambient temperature is lower. To do.

  The evaluation value calculation unit 31 normally calculates the evaluation value F (N) using the annealing coefficient Khigh corresponding to the high temperature ambient temperature map Mh. When the ambient temperature determination unit 33 determines that the ambient temperature is low, the ambient temperature map to be used is switched from the high temperature ambient temperature map Mh to the low temperature ambient temperature map Ml to obtain the low temperature ambient temperature map Ml. Use the corresponding annealing factor Klow.

  When the engine 20 is started, the temperature of the engine room 101 increases. In this case, even if the ambient temperature map used for calculating the evaluation value F (N) is the low temperature ambient temperature map Ml, the temperature is high. By switching to the atmospheric temperature map Mh, the annealing coefficient Khigh corresponding to the high temperature atmospheric temperature map Mh is used. Specific calculation of the evaluation value F (N) using the smoothing coefficient K by the evaluation value calculation unit 31 will be described later.

  As shown in FIG. 4, the Win / Wout restriction unit 32 has a threshold value Ftag for determining that the charge / discharge power of the power storage device 1 needs to be restricted. The threshold value Ftag includes a threshold value Ftag1 that regulates output restriction to the power storage device 1 and a threshold value Ftag2 that regulates input restriction to the power storage device 1.

  Then, the Win / Wout restriction unit 32 compares the evaluation value F (N) calculated by the evaluation value calculation unit 31 with the threshold values Ftag1 and Ftag2, so that the evaluation value F (N) is the threshold value Ftag1 or the threshold value Ftag2. When the value is exceeded, the charge / discharge power of the power storage device 1 is limited. Specific calculation of the charging power upper limit value Win and the discharging power upper limit value Wout when limiting, and the limitation based on these will be described later.

  Next, charge / discharge control of the power storage device 1 by the controller 30 will be described in detail with reference to FIGS. 5 and 6 are flowcharts showing the charge / discharge power control process of the power storage device 1 of the present embodiment. The control processing shown in FIGS. 5 and 6 is repeatedly performed at a preset time interval (cycle time). 7 and 8 are timing charts relating to the control processing of FIGS.

  In step S101 of the flowchart shown in FIG. 5, the on / off state of the ignition switch IG is confirmed. If the ignition switch IG is on (Yes), the process proceeds to step S102. If the ignition switch IG is off (No), the process proceeds to step S130 shown in FIG.

  In step S102, the starting state of the engine 20 is confirmed. If the engine 20 has been started (Yes), the process proceeds to step S103. If the engine 20 has not been started (No), the process proceeds to step S120.

  In step S103, as indicated by HV running in FIG. 7, the ambient temperature map used for calculating the evaluation value F (N) is switched to the high temperature ambient temperature map Mh as the engine 20 starts, and the process proceeds to step S104. . In step S104, the current value I of the discharge current or charging current is acquired based on the output signal of the current sensor 16, and the process proceeds to step S105. In step S105, the smoothing coefficient Khigh is calculated based on the current value I acquired in step S104 using the high-temperature atmosphere temperature map Mh, and the process proceeds to step S106.

  In step S106, an evaluation value F (N) is calculated based on the smoothing coefficient Khigh calculated in step S105 and the current value I. The controller 30 calculates the evaluation value F (N) larger as the temperature of the current-carrying part A is higher so as to correlate with the temperature of the current-carrying part A. Further, the controller 30 calculates the evaluation value F (N) larger as the ambient temperature of the energized component A is higher so as to correlate with the ambient temperature of the energized component A. The evaluation value F (N) can be calculated by the following formula 1.

  In Equation 1, N indicates the number of times the evaluation value F (N) is calculated. When the evaluation value F (N-1) calculated last time does not exist, the initial value of the evaluation value F (N) is used. As the annealing coefficient K, the annealing coefficient Klow or the annealing coefficient Khigh is set according to the ambient temperature of the energized component A. At present, the smoothing coefficient Khigh is set for the smoothing coefficient K as described above. The annealing coefficient K is a constant of 1 or more, and is a value set according to the temperature change of the energized component A and the ambient temperature of the energized component A.

  Here, since the smoothing coefficient Khigh corresponding to the high-temperature atmosphere temperature map Mh is set, the evaluation value F (N) is shown by a one-dot chain line characteristic in FIG. As shown in FIG. 4, the evaluation value F (N) shown in Expression 1 increases as the charge / discharge current flows through the power storage device 1. Until the evaluation value F (N) exceeds the threshold value Ftag2, the controller 30 performs input control with the allowable input power SWin as the upper limit value, and input restriction is started when the evaluation value F (N) exceeds the threshold value Ftag2. The input control is performed with the charging power upper limit value Win (<allowable input power SWin) calculated by the Win / Wout limiting unit 32.

  Further, until the evaluation value F (N) exceeds the threshold value Ftag1, output control is performed with the allowable output power SWout as an upper limit value. When the evaluation value F (N) exceeds the threshold value Ftag1, output restriction is started, and Win Output control is performed with the discharge power upper limit value Wout (<allowable output power SWout) calculated by the / Wout limiter 32.

  In step S107, it is determined whether or not the evaluation value F (N) calculated in step S106 exceeds the threshold value Ftag2, and if it exceeds (Yes), the process proceeds to step S108, where input restriction (allowable input) is performed. The maximum electric power value is reduced), and the charging power upper limit value Win is lower than the allowable input power SWin.

  Subsequently, in step S109, when it is determined that the evaluation value F (N) calculated in step S106 does not exceed the threshold value Ftag2 (No), or after the input restriction is started, the evaluation value F (N) Whether or not exceeds the threshold value Ftag1. When the evaluation value F (N) exceeds the threshold value Ftag1 (Yes), the process proceeds to step S110 to start output limitation (decrease the maximum value of allowable output input power) and to exceed the allowable output power SWout. The discharge power upper limit value Wout is changed.

  The charge power upper limit value Win and the discharge power upper limit value Wout in steps S108 and S110 can be calculated by, for example, the feedback control using the evaluation value F (N) as a parameter. In the present embodiment, the input / output restriction is controlled by different threshold values Ftag, and the input restriction start threshold value Ftag2 and the output restriction start threshold value Ftag1 are used. The threshold value Ftag can be calculated based on the energization current allowable value of the energization component A as described in Patent Document 1.

  Each value of charge power upper limit Win / discharge power upper limit Wout when evaluation value F (N) exceeds threshold value Ftag can be calculated as shown in Formula 2-1 and Formula 2-2 below. .

  In Expression 2-1, the charging power upper limit value Win is a correction term based on the feedback control using the evaluation value F (N) as a parameter to the allowable input power SWin calculated based on the SOC of the power storage device 1 and the battery temperature. It can be calculated by adding a certain Kin × (F−Ftag2). As described above, since the charging current is represented by a negative value, the charging power can also be represented by a negative value, and the correction term Kin × (F−Ftag2) that is a positive value with respect to the allowable input power SWin. Therefore, the charging power upper limit Win is a value larger than the allowable input power SWin (small value as an absolute value).

  In Expression 2-2, the discharge power upper limit value Wout is a correction term by feedback control using the evaluation value F (N) as a parameter to the allowable output power SWout calculated based on the SOC of the power storage device 1 and the battery temperature. It can be calculated by subtracting a certain Kout × (F−Ftag1). As described above, since the discharge current is represented by a positive value, the discharge power can also be represented by a positive value, and the correction term Kout × (F−Ftag1) which is a positive value with respect to the allowable output power SWout. Is subtracted, the discharge power upper limit value Wout is smaller than the allowable output power SWout.

  The correction terms Kin and Kout are coefficients, which are proportional control values of the correction term of the feedback control using the evaluation value F (N) as a parameter, and feedback for calculating the charge power upper limit value Win / discharge power upper limit value Wout. It is gain.

  In this way, the correction term Kin × (F−Ftag2) can be calculated as the input limit amount of the power storage device 1, and the correction term Kout × (F−Ftag1) can be calculated as the output limit amount of the power storage device 1. Then, a charge power upper limit Win / discharge power upper limit Wout lower than the allowable input power SWin / allowable output power SWout is calculated by the feedback control using the value of the evaluation value F (N) as a parameter. By performing input / output control of the power storage device 1 with the value Win / discharge power upper limit value Wout as an upper limit value, the temperature of the energized component A can be suppressed from exceeding the allowable temperature.

  On the other hand, in step S130 in FIG. 6, it is confirmed whether external charging is performed. That is, it is confirmed from the detection result of the current sensor 16 whether or not charging is being performed from the external power source 43. If external charging is being performed (Yes), the process proceeds to step S131, and if external charging is not being performed (No ) Proceeds to step S140.

  In step S131, as shown by external charging in FIG. 7, the time from when the external charging time Tc is started is measured by the ambient temperature determination unit 33, and the external charging time Tc and the predetermined time Ta are compared. When the external charging time Tc exceeds the predetermined time Ta (Yes), the process proceeds to step S132, and when the external charging time Tc has not reached the predetermined time Ta (No), the process returns.

  Here, the predetermined time Ta will be described. The predetermined time Ta is a time for determining whether the ambient temperature of the energized component A is low. That is, when the ignition switch IG is off and the external charging is performed over the predetermined time Ta, it can be estimated that the temperature of the engine room 101 is sufficiently lowered. For this reason, when the external charging time Tc exceeds the predetermined time Ta, it is determined that the ambient temperature of the energized component A is low. Therefore, in step S132, it is determined that the ambient temperature of the energized component A is sufficiently lowered and the ambient temperature is low, and the process proceeds to step S133.

  In step S133, as shown in FIG. 7, the ambient temperature map of the energized component A is switched from the high temperature ambient temperature map Mh to the low temperature ambient temperature map Ml, and the low temperature ambient temperature map Ml is used. Thereafter, the process proceeds to steps S104 and S105 shown in FIG. 5. In step S105, the smoothing coefficient Klow is calculated based on the current value I acquired in step S104 using the low-temperature atmosphere temperature map Ml.

  In step S106, an evaluation value F (N) is calculated based on the smoothing coefficient Klow and the current value I calculated in step S105. Since the evaluation value F (N) is calculated using the smoothing coefficient Klow, the evaluation value F (N) is calculated smaller than when the evaluation value F (N) is calculated using the smoothing coefficient Khigh. . In other words, when the ambient temperature of the energized component A is low, the evaluation value F (N) is calculated as a smaller value than when the ambient temperature of the energized component A is high. The control contents after step S106 are as described above.

  In step S140 in FIG. 6, as shown by neglected (external charging) in FIG. 8, it is confirmed whether the hybrid vehicle 100 is in the neglected state, that is, whether the engine 20 is stopped and parked. In step S140, the IG off time Ti from when the ignition switch IG is turned off is measured by the ambient temperature determination unit 33, and the IG off time Ti is compared with the predetermined time Tb. When the IG off time Ti exceeds the predetermined time Tb (Yes), the process proceeds to step S141, and when the IG off time Ti does not reach the predetermined time Tb (No), the process returns.

  The predetermined time Tb is a time for determining whether or not the ambient temperature of the energized component A is low, like the predetermined time Ta. That is, when the off time of the ignition switch IG exceeds the predetermined time Tb, it can be estimated that the temperature of the engine room 101 is sufficiently lowered. For this reason, when the OFF time of the ignition switch IG exceeds the predetermined time Tb, it is determined that the ambient temperature of the energized component A is low. Therefore, in step S141, it is determined that the ambient temperature of the energized component A is sufficiently lowered and the ambient temperature is low, and the process proceeds to step S142.

  In step S142, as shown in FIG. 8, the ambient temperature map of the energized component A is switched from the high temperature ambient temperature map Mh to the low temperature ambient temperature map Ml, and the process proceeds to step S143 using the low temperature ambient temperature map Ml.

  In step S143, as shown by neglected (external charging) in FIG. 8, it is confirmed again whether external charging is performed at this time. From the detection result of the current sensor 16, it is confirmed whether or not charging is performed from the external power source 43. If external charging is in progress (Yes), the process proceeds to steps S104 and S105 shown in FIG. Using the temperature map Ml, the smoothing coefficient Klow is calculated based on the current value I acquired in step S104. The subsequent control contents are as described above. If no external charging is performed (No), the process returns.

  In FIG. 8, external charging is started after the elapse of the predetermined time Tb, but external charging may be started before the elapse of the predetermined time Tb.

  Returning to FIG. 5, in step S120, it is confirmed whether or not the ambient temperature map used during EV traveling is the low temperature ambient temperature map Ml. As shown in EV travel in FIGS. 7 and 8, when the atmospheric temperature map is switched to the low-temperature atmospheric temperature map Ml in step S133 or step S142 via step S130 before reaching step S120. In step S120, the low-temperature atmosphere temperature map Ml is set.

  However, when step S120 is reached directly without going through step S130, for example, when the ignition switch IG is turned off and turned on immediately, the external charging time Tc has not reached the predetermined time Ta. In addition, since the IG OFF time has not reached the predetermined time Tb, the atmospheric temperature map is not switched to the low temperature atmospheric temperature map Ml, and the normal high temperature atmospheric temperature map Mh is set in the atmospheric temperature map. Yes.

  In other words, if it is determined that the ambient temperature of the energized component A in a state before the ignition switch IG is turned on is low, the low temperature ambient temperature map Ml is used, and the state before the ignition switch IG is turned on. If it is determined that the ambient temperature of the current-carrying component A is not low (high), the high-temperature ambient temperature map Mh is used.

  Therefore, in step S120, if the atmospheric temperature map is set to the low temperature atmospheric temperature map Ml (Yes), the process proceeds to step S121, and if it is set to the high temperature atmospheric temperature map Mh (No), the process proceeds to step S103. move on.

  In step S121, it is confirmed that the ambient temperature map to be used is the low temperature ambient temperature map Ml, and the process proceeds to step S104. The control contents after step S104 are as described above.

  As described above, when it is determined that the ambient temperature of the energized component A is low, the ambient temperature map is switched to the low temperature ambient temperature map Ml, and the low temperature ambient temperature map is used to calculate the evaluation value F (N). Since the smoothing coefficient Klow corresponding to Ml is used, the evaluation value F (N) is calculated to be small. When the evaluation value F (N) is small, the time until the evaluation value F (N) exceeds the threshold value Ftag becomes longer, and the timing at which the input / output restriction associated with the suppression of the temperature rise of the energized component A can be delayed. .

  The delay of the timing at which this input / output restriction intervenes will be described in detail. In FIG. 4, the solid line represents the evaluation value F (N) and the upper limit value of the input / output power when the evaluation value F (N) is calculated using the annealing coefficient Klow corresponding to the low temperature ambient temperature map Ml of FIG. The evaluation value F (N) and the input / output power when the evaluation value F (N) is calculated using the annealing coefficient Khgih corresponding to the high temperature ambient temperature map Mh in FIG. The change in the upper limit value is shown.

  In the high temperature atmosphere, the evaluation value F (N) exceeds the threshold value Ftag2 at the time t1, but in the low temperature atmosphere, it can be energized for a longer time than in the high temperature atmosphere, and thus has a value larger than the annealing coefficient Khgih. By applying the set annealing coefficient Klow, the rate of increase of the evaluation value F (N) is reduced. For this reason, since the evaluation value F (N) exceeds the threshold value Ftag2 at time t3, which is longer in time than time t1, the timing at which the input restriction intervenes can be delayed.

  Further, in the high temperature atmosphere, the evaluation value F (N) exceeds the threshold value Ftag1 at time t2, but in the low temperature atmosphere, the evaluation is performed at time t4 having a longer elapsed time than time t2 by applying the coefficient Klow. Since the value F (N) exceeds the threshold value Ftag1, the timing at which the output restriction intervenes can be delayed.

  Thus, in this embodiment, when it is determined that the ambient temperature of the energized component A is a low temperature atmosphere, the annealing coefficient K for calculating the evaluation value F (N) is a high temperature atmosphere (low temperature atmosphere). The evaluation value F (N) is calculated according to the ambient temperature of the energized component A. Note that the low temperature ambient temperature map Ml and the high temperature ambient temperature map Mh shown in FIG. 3 are set such that the values of the smoothing coefficients Klow and Khgih decrease as the flowing current value increases. The annealing coefficient Klow is set to be larger than the annealing coefficient Khgih.

  According to this embodiment, when the predetermined time Ta has elapsed since the hybrid vehicle 100 was externally charged, or when the predetermined time Tb had elapsed since the ignition switch IG of the hybrid vehicle 100 was turned off, It is determined that the ambient temperature has changed from a high state to a low state. Then, when calculating the evaluation value F (N), the annealing coefficient Klow corresponding to the low temperature ambient temperature map Ml is used. When the smoothing coefficient Klow is used, the evaluation value F (N) is calculated smaller than when the smoothing coefficient Khgih is used.

  For this reason, when the ambient temperature of the current-carrying component A is low, the time until the evaluation value F (N) exceeds the threshold value Ftag becomes longer, and the input / output restriction accompanying the suppression of the temperature rise of the current-carrying component A intervenes. Can be delayed. As a result, more power can be charged in the power storage device 1, and more power can be discharged from the power storage device 1.

  Therefore, the charging power to the power storage device 1 at the time of external charging can be increased, and the distance that can be EV traveled without driving the engine 20 can be increased. Further, the discharge power from the power storage device 1 during EV traveling can be increased, and the EV traveling distance without driving the engine 20 can be increased similarly in EV traveling after external charging. Therefore, deterioration of fuel consumption can be suppressed.

  Further, when the ambient temperature of the energized component A is high, that is, the ambient temperature map is switched to the high temperature ambient temperature map Mh according to the start of the engine 20, an excessive temperature rise of the energized component A can be suppressed. .

  In the above-described embodiment, two maps, the high temperature ambient temperature map Mh and the low temperature ambient temperature map Ml, are used by switching, but the ambient temperature map is not limited to two, and two or more ambient temperature maps are used. May be. For example, as indicated by a broken line in FIG. 9, an intermediate temperature map Mm may be added in addition to the above two maps. In this case, the ambient temperature map is switched by setting the lengths of the predetermined times Ta and Tb in stages. In accordance with the switching of the atmospheric temperature map, the annealing coefficient K is set to any one of Klow, Kmid, and Khgih. In this way, by using a plurality of atmosphere temperature maps, it is possible to calculate a highly accurate evaluation value F (N) corresponding to the atmosphere temperature of the energized component A.

  In the above-described embodiment, the ambient temperature of the energized component A is determined based on the driving state of the engine 20. However, the energization is performed based on temperature information from the temperature sensor 18 that detects the temperature in the engine room 101. The ambient temperature of the part A may be determined.

  As shown in FIG. 1, the engine room 101 is provided with a temperature sensor 18 that detects the temperature in the engine room 101. In this case, if No in step S101 shown in FIG. 5, the process proceeds to step S200 shown in FIG. In step S200, it is confirmed whether CAN is functioning normally. If the CAN is functioning normally (Yes), the process proceeds to step S201. If the CAN is not functioning normally due to a failure or the like (No), the process proceeds to step S204.

  In step S201, the detected temperature te of the engine room 101 is acquired based on the output signal of the temperature sensor 18, and the process proceeds to step S202. In step S202, the detected temperature te of the temperature sensor 18 is compared with a predetermined temperature ta. When the detected temperature te is lower than the predetermined temperature ta (Yes), the process proceeds to step S203, and when the detected temperature te is equal to or higher than the predetermined temperature ta (No), the process returns.

  The predetermined temperature ta is a temperature for determining whether or not the ambient temperature of the energized component A is low. That is, when the detected temperature te of the engine room 101 is lower than the predetermined temperature ta, it is determined that the ambient temperature of the energized component A is low. If the detected temperature te of the engine room 101 is equal to or higher than the predetermined temperature ta, it is determined that the ambient temperature of the energized component A is high.

  In step S203, the ambient temperature map is switched to the low temperature ambient temperature map Ml, and the process proceeds to step S104 in FIG.

  In step S204, the high-temperature atmosphere temperature map Mh is used regardless of the detected temperature te of the temperature sensor 18. When the ambient temperature of the current-carrying component A cannot be accurately determined, in order to suppress overheating of the current-carrying component A, the smoothing coefficient K used to calculate the evaluation value F (N) is set to the warming factor Khigh on the high temperature side. Secure to.

  Thus, by using the temperature sensor 18, it becomes possible to accurately detect the ambient temperature of the energized component A, and an ambient temperature map (annealing coefficient) suitable for the ambient temperature of the energized component A is used. be able to.

  DESCRIPTION OF SYMBOLS 1 Power storage device, 12, 13 Power cable, 15 Voltage monitoring unit, 16 Current sensor, 17, 18 Temperature sensor, 20 Engine, 30 Controller, 31 Evaluation value calculation part, 32 Win / Wout restriction part, 33 Atmosphere temperature determination part, 34 Ambient temperature characteristic storage unit, 43 External power supply, 100 hybrid vehicle, 101 engine room, A energized part, F evaluation value, Ftag, Ftag1, Ftag2 threshold, IG ignition switch, K, Klow, Khigh coefficient, Mh high temperature ambient temperature map , Ml Low temperature ambient temperature map, SMR-B, SMR-G, SMR-P system main relay, SWin allowable input power, SWout allowable output power, Ta, Tb predetermined time, Tc external charging time, Ti IG off time, Win charging Electric power Limit values, Wout discharging power upper limit values.

Claims (1)

A charge / discharge control device for a power storage device that includes a current-carrying component that supplies charge / discharge power between a power storage device and a vehicle driving motor, and that limits charge / discharge power according to a temperature of the current-carrying component,
An atmospheric temperature determination unit for determining the atmospheric temperature of the energized parts disposed in the engine room;
The determination result of the ambient temperature determining section, and the current value detected at the time of charge and discharge of the power storage device, based on the evaluation value calculation unit for calculating an evaluation value for evaluating the temperature level of the current-carrying members,
A power limiting unit that limits charge / discharge power of the power storage device when the evaluation value exceeds a threshold;
With
The evaluation value calculation unit calculates the evaluation value to be small based on a decrease in the ambient temperature when the ambient temperature determination unit determines that the ambient temperature of the energized component has decreased .
Calculating the evaluation value as the current value increases,
Charge and discharge control device for a power storage device according to claim.

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