JP4835383B2 - Control device and control method for power supply unit, program for causing computer to realize the method, and recording medium recording the program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress deterioration due to overdischarging of a secondary battery and worm the secondary battery at low temperature in a short time in a power supply unit including a load, the secondary battery, and a converter. <P>SOLUTION: ECU executes a program including the following steps: a step (S104) of determining whether or not it is required to supply power equivalent to a value obtained by increasing the rated voltage value (VB) of the battery to a motor generator based on the request torque value T(MG) of the motor generator; a step (S108) of, after it is determined that the voltage-increased power need not be supplied (YES at S104), determining whether or not it is required to warm the battery based on the temperature of the battery; and a step (S110) of, after it is determined that the battery need be warmed (YES at S108), outputting a voltage increasing command to the step-up converter so that the output voltage value VH of the step-up converter becomes equal to its maximum voltage value VH(MAX). <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a control technology for a power supply unit, and more particularly to a control technology for a power supply unit that supplies power obtained by boosting a rated voltage of a secondary battery by a converter to a load.

  There are known an electric vehicle that travels by the output of a motor that uses a battery as a power source, and a hybrid vehicle that travels by the output of an engine and the output of a motor that uses a battery as a power source. The battery, which is the power source of the motor, has a higher internal resistance and lower input / output characteristics as the temperature is lower. For this reason, when the battery temperature is low, the motor cannot be fully discharged or the regenerative energy can not be sufficiently charged, and the power performance and fuel consumption performance of the vehicle are reduced. In order to avoid such degradation in performance, it is necessary to warm up the battery early to restore the input / output characteristics of the battery. As a technique for warming up the battery when the battery temperature is low, for example, there is a technique disclosed in Japanese Patent Laid-Open No. 2001-268715 (Patent Document 1).

  The hybrid electric vehicle disclosed in this publication includes a means for traveling by the power of the engine, a means for traveling by the power of the motor using the battery as a power source, and a battery temperature detecting means for detecting the temperature of the battery. And an engine output command for setting a command value to a value obtained by reducing the driving force driven by the engine power by a predetermined value when the battery temperature detected by the battery temperature detecting means is lower than the predetermined temperature. Means, motor output command means for setting a value obtained by increasing a driving force driven by the power of the motor by a predetermined value as a command value, a discharge command to the battery based on the engine output command value and the motor output command value Discharge command means for providing.

According to the hybrid electric vehicle disclosed in this publication, when the battery temperature is lower than a predetermined temperature, the motor output command value is increased. Therefore, compared with the case where battery temperature is higher than predetermined temperature, the discharge electric power from a battery can be made higher and a battery can be warmed up. Further, as the motor output command value is increased, the engine output command value is decreased. Therefore, the input / output characteristics of the battery can be improved without any influence on the traveling of the vehicle.
JP 2001-268715 A

  However, in the hybrid electric vehicle disclosed in Patent Document 1, when the battery temperature is low, the output characteristics of the battery are degraded as described above. Therefore, in practice, the discharge power of the battery is limited when the battery temperature is low, and the battery may not be warmed up early. Furthermore, if the discharge is continued for a long time at a low temperature of the battery, the battery may be overdischarged and may be significantly deteriorated.

  The present invention has been made to solve the above-described problems, and its purpose is to suppress deterioration due to overdischarge of the secondary battery in the power supply unit including the secondary battery and the converter, It is an object to provide a control device and control method for a power supply unit that can warm up a low-temperature secondary battery at an early stage, a program for causing a computer to implement the method, and a recording medium on which the program is recorded.

  A control device according to a first aspect of the present invention includes a secondary battery that supplies power to a load, and a converter that is provided between the load and the secondary battery and transforms and outputs an input voltage by turning on and off the switching element. Control the power supply unit. The control device includes a means for calculating an output required for the load, a transformation determination means for determining whether or not a transformation by the converter is necessary based on the requested output, and a secondary battery. A means for detecting the temperature of the battery, a temperature judging means for judging whether or not the temperature of the secondary battery is equal to or lower than a predetermined temperature, and the transformer judging means judges that no transformation is necessary, and And a control means for controlling the converter to operate when the temperature determination means determines that the temperature of the secondary battery is equal to or lower than a predetermined temperature. The control method according to the sixth invention has the same requirements as the control device according to the first invention.

  According to the first or sixth invention, the rated voltage of the secondary battery is transformed by the converter and supplied to the load. Since the secondary battery has low output characteristics when the temperature is low, there are cases where the power supply to the load cannot be sufficiently performed. Therefore, it is necessary to warm up the secondary battery early to recover the input / output characteristics of the secondary battery. Therefore, even if it is determined that the output required for the load is low and that transformation by the converter is not necessary, the converter is operated when the secondary battery has a low temperature equal to or lower than a predetermined temperature. For example, the converter is operated so as to boost the rated voltage of the secondary battery to the maximum boost value. When the converter is operated, a current (ripple current) in which the AC component is superimposed on the DC component is generated due to ON / OFF of the switching element, and a charge / discharge current in which the AC component is superimposed on the DC component flows in the secondary battery. . Therefore, even when the direct current component of the charge / discharge current is small, heat generation inside the secondary battery can be promoted by the alternating current component, and the secondary battery can be warmed up earlier. Further, when the converter is controlled so that the AC component is larger than the DC component of the charge / discharge current, the charge / discharge is repeated each time the switching element is turned on / off. Therefore, it is possible to prevent overdischarge due to the discharge being continued for a long time. As a result, in the power supply unit including the secondary battery and the converter, the control device for the power supply unit that can quickly warm the low-temperature secondary battery while suppressing deterioration due to overdischarge of the secondary battery. And a control method can be provided.

  In the control device according to the second aspect of the invention, in addition to the configuration of the first aspect of the invention, the transformation determination means includes means for determining whether or not boosting by the converter is necessary. The control device further includes means for controlling the converter so as to boost the rated voltage of the secondary battery to a value corresponding to the required output when it is determined by the transformation determining means that boosting is necessary. . The control means includes means for controlling the converter so as to boost the rated voltage to a predetermined value. The control method according to the seventh invention has the same requirements as the control device according to the second invention.

  According to the second or seventh aspect of the invention, when it is determined that boosting by the transformation determining means is necessary, the rated voltage of the secondary battery is boosted to a value corresponding to the output required from the load. On the other hand, when it is determined that no voltage transformation is required by the voltage transformation judging means and the secondary battery is at a low temperature, the rated voltage of the secondary battery is boosted to a predetermined value. Thereby, irrespective of the magnitude | size of output requested | required of load, the magnitude | size of the alternating current component of the discharge current from a secondary battery can be made into a predetermined value. Therefore, for example, the secondary battery can be warmed up earlier by boosting the rated voltage of the secondary battery to the maximum boost value so that the magnitude of the AC component of the discharge current is maximized.

  In the control device according to the third invention, in addition to the configuration of the second invention, the predetermined value is a maximum boost value in the converter. The control method according to the eighth invention has the same requirements as the control device according to the third invention.

  According to the third or eighth invention, the rated voltage of the secondary battery is boosted to the maximum boost value in the converter. At this time, the amplitude of the alternating current component of the discharge current is maximized, and Joule heat generated inside the secondary battery is maximized. Therefore, the secondary battery can be warmed up in the shortest time.

  In the control device according to the fourth invention, in addition to the configuration of any one of the first to third inventions, the power supply unit is provided between the converter and the load, and converts the input current and outputs it. Further included. The control device, based on the required output, based on the means for calculating the power required from the load, the means for detecting the output voltage of the converter, the required power and the output voltage, Means for controlling the current converted by the inverter so that the required power is supplied to the load. The control method according to the ninth aspect has the same requirements as the control device according to the fourth aspect.

  According to the fourth or ninth invention, for example, when the secondary battery is at a low temperature and maximum boosted by the converter, the current value converted by the inverter is reduced. Therefore, it is possible to supply electric power according to demand to the load while boosting the voltage by the converter to warm up the battery.

  In the control device according to the fifth invention, in addition to the configuration of any one of the first to fourth inventions, the power supply unit is mounted on the vehicle. The load is a rotating electrical machine that generates a driving force of the vehicle by the power of the secondary battery and generates regenerative power when the vehicle is braked. The control method according to the tenth invention has the same requirements as the control device according to the fifth invention.

  According to the fifth or tenth aspect of the invention, even when the driving force required for the vehicle is low and the electric power required from the rotating electrical machine is low, when the secondary battery is at a low temperature, the secondary battery is brought to an early stage by boosting the converter. Warmed up. As a result, the input / output characteristics of the secondary battery can be recovered earlier, the driving force of the vehicle can be sufficiently output to the rotating electrical machine, and more regenerative power generated by the rotating electrical machine can be recovered during braking of the vehicle. it can.

  A program according to an eleventh invention is a program for causing a computer to execute the control method according to any of the sixth to tenth inventions. A recording medium according to a twelfth aspect of the invention is a recording medium in which a program for causing a computer to execute the control method according to any of the sixth to tenth aspects of the invention is recorded in a computer-readable manner.

  According to the eleventh or twelfth invention, the control method according to any of the sixth to tenth inventions can be realized using a computer (which may be general purpose or dedicated).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  With reference to FIG. 1, a vehicle equipped with a control device for a power supply unit according to the present embodiment will be described. This vehicle includes a battery 100, an inverter 200, a motor generator (MG) 300, a smoothing capacitor 400, an ECU (Electronic Control Unit) 600, and a boost converter 800. The power supply unit according to the embodiment of the present invention includes battery 100, boost converter 800, smoothing capacitor 400, and inverter 200, and supplies power of battery 100 to MG 300.

  The battery 100 is an assembled battery in which a plurality of modules in which a plurality of cells are connected in series are further connected in series. As the temperature of the battery 100 decreases, the internal resistance increases and the input / output characteristics deteriorate.

  Inverter 200 includes six IGBTs (Insulated Gate Bipolar Transistors) and six diodes connected in parallel to each IGBT so that a current flows from the emitter side to the collector side of the IGBT. Inverter 200 causes MG 300 to function as a motor or a generator based on a control signal from ECU 600.

  Inverter 200 converts DC power supplied from battery 100 to AC power and supplies it to MG 300 when MG 300 functions as a motor. The inverter 200 controls the electric power (current magnitude) supplied to the MG 300 by turning on / off (energizing / cutting off) the gate of each IGBT, whereby the MG 300 is brought into an output state required by a control signal from the ECU 600. Control to be.

  Inverter 200 converts AC power generated by MG 300 into DC power and charges battery 100 when MG 300 functions as a generator. The inverter 200 controls the regenerative power (the magnitude of the regenerative current) generated by the MG 300 by turning on / off the gates of the IGBTs, so that the regenerative braking force (regenerative torque) required by the control signal from the ECU 600 is obtained. Control to act on the vehicle.

  MG 300 is a three-phase AC motor and a generator that generates electric power during regenerative braking of the vehicle. The rotation shaft of MG 300 is finally connected to a drive shaft (not shown) of the vehicle. The vehicle travels with the driving force from MG300.

  Smoothing capacitor 400 is connected in parallel with inverter 200. Smoothing capacitor 400 temporarily accumulates electric charges in order to smooth the electric power supplied from battery 100 or the electric power supplied from inverter 200. The smoothed power is supplied to the inverter 200 or the battery 100.

  Boost converter 800 is connected to ECU 600 and provided between battery 100 and smoothing capacitor 400. Boost converter 800 includes first switching element (SW (1)) 810, second switching element (SW (2)) 820, and diodes connected in parallel to SW (1) 810 and SW (2) 820, respectively. 812 and 822, a reactor 830 that prevents a current change, and a capacitor 840.

  SW (1) 810 and SW (2) 820 are IGBTs that are turned on / off (switched) by PWM (Pulse Width Modulation) control.

  When SW (1) 810 and SW (2) 820 are turned on / off by a control signal from ECU 600, output voltage value VH of boost converter 800 is input voltage value VL (normally rated voltage value VB of battery 100). Is a boosted value.

  When the control signal from ECU 600 is stopped and ON / OFF of SW (1) 810 and SW (2) 820 is stopped, output voltage value VH of boost converter 800 remains at input voltage value VL.

  ECU 600 is connected to battery temperature sensor 102, first voltmeter 802, second voltmeter 804, vehicle speed sensor 702, accelerator opening sensor 704, and brake pedal force sensor 706.

  Battery temperature sensor 102 detects the temperature of battery 100 and transmits a signal representing the battery temperature to ECU 600. First voltmeter 802 detects input voltage value VL of boost converter 800 and transmits a signal representing input voltage value VL to ECU 600. Second voltmeter 804 detects output voltage value VH of boost converter 800 and transmits a signal representing output voltage value VH to ECU 600.

  Vehicle speed sensor 702 detects the vehicle speed and transmits a signal representing the vehicle speed to ECU 600. The accelerator opening sensor 704 detects the amount of depression of the accelerator pedal (accelerator opening) by the driver of the vehicle, and transmits a signal representing the accelerator opening to the ECU 600. The brake pedal force sensor 706 detects the brake pedal force by the driver of the vehicle and transmits a signal representing the brake pedal force to the ECU 600.

  ECU 600 executes a program stored in a ROM (Read Only Memory) based on signals transmitted from sensors such as vehicle speed sensor 702, accelerator opening sensor 704, and brake pedal force sensor 706. By this program, inverter 200, boost converter 800, and the like are controlled, and the vehicle is controlled to travel in a desired state. This program may be recorded on a recording medium and distributed in the market.

  Further, ECU 600 is based on a map using the temperature of battery 100 or SOC (State Of Charge) as a parameter, etc., and charging power limit value (maximum value of charged power) WIN and discharge power limit value ( The maximum value of electric power discharged) WOUT is calculated. The charge power limit value WIN and the discharge power limit value WOUT are calculated so as to be smaller as the battery 100 is at a lower temperature (that is, as the input / output characteristics of the battery 100 are lower). ECU 600 controls inverter 200 and boost converter 800 so as to limit the charge / discharge power of battery 100 to charge power limit value WIN and discharge power limit value WOUT. Thereby, overdischarge and overcharge of the battery 100 are prevented.

  With reference to FIG. 2, the current flowing through boost converter 800 will be described. SW (1) 810 and SW (2) 820 are switched at a high frequency of about 10 KHz, for example, by a control signal from ECU 600, and are controlled to be different from each other as shown in FIG.

  When SW (2) 820 is turned on (SW (1) 810 is turned off), the current from battery 100 is charged in reactor 830, and the voltage in reactor 830 is increased. When SW (2) 820 is turned off (SW (1) 810 is turned on), the electric power boosted in reactor 830 is discharged to inverter 200.

  By repeating such charging and discharging of the reactor 830, the current I (L) flowing through the reactor 830 is superimposed with the AC component IL (AC) on the DC component IL (DC) as shown in FIG. It becomes current (current). The amplitude value A (L) of the AC component IL (AC) increases as the output voltage value VH of the boost converter 800 increases.

  With reference to FIG. 3, a functional block diagram of the control device for the power supply unit according to the present embodiment will be described. As shown in FIG. 3, the control device includes a required torque value calculation unit 610, a required power value calculation unit 620, a boost determination unit 630 connected to the required torque value calculation unit 610, and a warm-up determination unit 640. , Converter command unit 650 connected to boost determination unit 630 and warm-up determination unit 640, and inverter command unit 660 connected to required power value calculation unit 620 and converter command unit 650.

  The required torque value calculation unit 610 is a torque required for the MG 300 based on signals transmitted from sensors such as the vehicle speed sensor 702, the accelerator opening sensor 704, and the brake pedal force sensor 706, and programs and maps stored in the ROM. A value (required torque value) T (MG) is calculated.

  The required power value calculation unit 620 is a power required from the MG 300 based on signals transmitted from sensors such as the vehicle speed sensor 702, the accelerator opening sensor 704, and the brake pedal force sensor 706, and programs and maps stored in the ROM. A value (required power value) P (MG) is calculated.

  Boost determination unit 630 determines whether or not it is necessary to supply MG 300 with power obtained by boosting rated voltage VB of battery 100 based on required torque value T (MG).

  Warm-up determination unit 640 determines whether or not it is necessary to warm up battery 100 based on the signal from battery thermometer 102.

  Converter command unit 650 outputs a command (control signal) such that output voltage value VH corresponds to required torque value T (MG) and the determination result of warm-up determination unit 630 to boost converter 800.

  Inverter command unit 660 outputs a command (control signal) to inverter 200 based on required power value P (MG) and output voltage value VH.

  The control device according to the present embodiment having such a functional block is read out from a CPU (Central Processing Unit) and a memory and a memory included in the ECU even in hardware mainly composed of a digital circuit or an analog circuit. It can also be realized by software mainly composed of programs executed by the CPU. In general, it is said that it is advantageous in terms of operation speed when realized by hardware, and advantageous in terms of design change when realized by software. Below, the case where a control apparatus is implement | achieved as software is demonstrated. Note that a recording medium on which such a program is recorded is also an embodiment of the present invention.

  With reference to FIG. 4, a control structure of a program executed by ECU 600 which is the control device for the power supply unit according to the present embodiment will be described. Note that this program is repeatedly executed at a predetermined cycle time.

  In step (hereinafter, step is abbreviated as S) 100, ECU 600 determines required torque value T based on signals transmitted from sensors such as vehicle speed sensor 702, accelerator opening sensor 704, and brake pedal force sensor 706. (MG) is calculated.

  In S102, ECU 600 calculates required power value P (MG) based on signals transmitted from sensors such as vehicle speed sensor 702, accelerator opening sensor 704, and brake pedal force sensor 706. ECU 600 may calculate required power value P (MG) based on required torque value T (MG).

  In S104, ECU 600 determines whether or not it is necessary to supply electric power obtained by boosting rated voltage value VB of battery 100 to MG 300 based on required torque value T (MG). ECU 600 determines that it is necessary to supply boosted electric power, for example, when required torque value T (MG) is larger than a predetermined threshold value. ECU 600 may determine whether or not it is necessary to supply MG 300 with power obtained by boosting rated voltage value VB of battery 100 based on required power value P (MG). If it is necessary to supply the boosted power (YES in S104), the process proceeds to S106. Otherwise (NO in S104), the process proceeds to S108.

  In S106, ECU 600 outputs a boost command to boost converter 800 so that output voltage value VH becomes a value VH (MG) corresponding to required torque value T (MG).

  In S108, ECU 600 determines whether or not battery 100 needs to be warmed up. For example, ECU 600 determines that battery 100 needs to be warmed up when the battery temperature transmitted from battery thermometer 102 is equal to or lower than a predetermined temperature. If it is necessary to warm up (YES in S108), the process proceeds to S110. Otherwise (NO in S108), the process proceeds to S112.

  In S110, ECU 600 outputs a boost command to boost converter 800 so that output voltage value VH becomes maximum voltage value VH (MAX).

  In S112, ECU 600 stops the command to boost converter 800 so that output voltage value VH becomes rated voltage value VB of battery 100.

  In S114, ECU 600 calculates a current value I (IN) to be converted by inverter 200 based on output voltage value VH and required power value P (MG). For example, ECU 600 calculates a value obtained by dividing required power value P (MG) by output voltage value VH as current value I (IN).

  In S116, ECU 600 outputs a conversion command to inverter 200 so that current having a magnitude of current value I (IN) is converted by inverter 200.

  An operation of the power supply unit controlled by ECU 600 that is the control device according to the present embodiment based on the above-described structure and flowchart will be described.

  When the driving of the vehicle is started, a required torque value T (MG) and a required power value P (MG) of MG 300 are calculated (S100, S102).

  By the way, when the temperature of the battery 100 is low, the internal resistance of the battery 100 increases and the input / output characteristics deteriorate. Therefore, the discharge power limit value WOUT becomes a small value. Thereby, even when the required torque value T (MG) is high, the battery 100 may not be sufficiently discharged. Further, even when MG 300 generates large regenerative power, battery 100 may not be sufficiently charged.

  Therefore, the required torque value T (MG) is smaller than a predetermined threshold value, and it is determined that it is not necessary to supply power obtained by boosting the rated voltage value VB of the battery 100 (NO in S104). However, if battery temperature is equal to or lower than a predetermined temperature, it is determined that battery 100 needs to be warmed up (YES in S108), and output voltage value VH of boost converter 800 is equal to maximum voltage value VH ( MAX) (S110).

  Thereby, the current I (L) flowing through the reactor 830 is a current in which the AC component IL (AC) is superimposed on the DC component IL (DC) as described above. Current I (L) flowing through reactor 830 flows to battery 100 via capacitor 840. As a result, the current I (B) flowing through the battery 100 is a current obtained by superimposing the AC component IB (AC) on the DC component IB (DC), as shown in FIG.

  Heat generation inside the battery 100 is promoted by the AC component IB (AC) in addition to the DC component IB (DC). Therefore, as shown in FIG. 6, battery 100 can be warmed up earlier than when only DC component IB (DC) is used (that is, when boosting by boost converter 800 is not performed).

  As a result, the input / output characteristics of the battery 100 can be recovered earlier in case the required torque value T (MG) subsequently increases or the MG 300 generates a large amount of regenerative power, and the power performance of the vehicle It can suppress that the recovery rate of regenerated electric power falls.

  Further, the output voltage value VH is boosted to the maximum voltage value VH (MAX), and the amplitude A (L) of the current I (L) flowing through the reactor 830 is maximized. Therefore, the amplitude A (B) of the alternating current component IB (AC) of the current I (B) flowing through the battery 100 is also maximized, and Joule heat generated inside the battery 100 is maximized. Thereby, the battery 100 can be warmed up in the shortest time.

  Furthermore, as shown in FIG. 6, when the amplitude A (B) of the AC component IB (AC) is larger than the DC component IB (DC) of the current I (B) flowing through the battery 100, SW (1) 810 and SW (2) Every time 820 is turned on / off, charging / discharging of the battery 100 is repeated. Therefore, overdischarge due to continuous discharge for a long time can be prevented when the battery 100 is at a low temperature.

  The current value I (IN) converted by the inverter 200 is controlled to a value obtained by dividing the required power value P (MG) by the output voltage value VH (S114, S116). That is, the current value I (IN) converted by the inverter 200 is controlled to be small in accordance with the boosted output voltage value VH. Therefore, the MG 300 is supplied with the power of the required power value P (MG).

  As described above, according to the control device for the power control unit according to the present embodiment, the required torque of the motor generator is small, and it is not necessary to supply the motor generator with the electric power obtained by boosting the rated voltage of the battery. However, when the battery temperature is low, the boost converter is controlled so as to boost at the maximum boost value. Thereby, since the electric current containing an alternating current component flows through the battery, heat generation inside the battery is further promoted. Further, if the amplitude of the AC component is larger than the DC component of the current flowing through the battery, the battery is repeatedly charged and discharged each time the switching element of the boost converter is turned on / off. Therefore, it is possible to prevent overdischarge due to the discharge being continued for a long time. Thereby, the battery can be warmed up earlier while suppressing deterioration due to overdischarge of the battery.

  In the present embodiment, the case where the AC component is included in the discharge current of battery 100 has been described. However, in the control device for the power control unit according to the present invention, the current including the AC component is the discharge current of battery 100. It is not limited to being. That is, even when an AC component is included in the charging current of battery 100, the battery can be warmed up earlier.

<First Modification>
In the above-described embodiment, the power supply unit that supplies only the power from the battery 100 to the MG 300 has been described. However, the power supply unit to which the control device according to the present invention can be applied is not limited thereto.

  For example, as shown in FIG. 7, as compared with the power supply unit according to the first embodiment, the battery 100 is connected in parallel with the battery 100 between the smoothing capacitor 400 and the inverter 200, and hydrogen and oxygen in the air are supplied. The control device according to the present invention can also be applied to a power supply unit including a fuel cell 2010 that generates electricity through a chemical reaction.

  In such a power supply unit, it is possible to optimally control the power of the battery 100 and the power of the fuel cell 2010 according to the load of the MG 300. For example, when the required torque value T (MG) of the MG 300 is low, only the electric power from the fuel cell 2010 is supplied to the MG 300, and the required torque value T (MG) of the MG 300 is high and the electric power of the fuel cell 2010 is insufficient. In this case, the power of the battery 100 is replenished.

  Thus, even when the required torque value T (MG) is low (YES in S104), if the battery temperature is low (YES in S108), in preparation for the case where the power of the battery 100 is required. The boost converter 800 is controlled to boost the voltage (S110). Thereby, when battery 100 is warmed up early and required torque value T (MG) of MG 300 becomes high, the power of battery 100 can be sufficiently supplemented.

  Instead of the fuel cell 2010, for example, a capacitor having better input / output characteristics than the battery 100 may be provided. Even in this case, the battery 100 can be warmed up early and the input / output characteristics of the battery 100 can be recovered early.

<Second Modification>
In the above-described embodiment, the vehicle on which the control device for the power supply unit is mounted is described as an electric vehicle that travels only by the driving force from the MG 300, but the vehicle on which the power supply unit according to the present invention is mounted is Not limited to electric vehicles. For example, as shown in FIG. 8, it may be a hybrid vehicle.

  Compared with the vehicle according to the first embodiment, this hybrid vehicle replaces inverter 200 and MG300 with engine 1000, MG (1) 1300, MG (2) 1310, engine 1000 and MG ( 1) Power split device 1400 connected to 1300 and MG (2) 1310, inverter (1) 1200 connected to MG (1) 1300, and inverter (2) 1210 connected to MG (2) 1310 A reduction gear 1040, a drive shaft 1050, and a drive wheel 1060.

  This vehicle travels when power from at least one of engine 1000 and MG (2) 1310 is transmitted to drive wheels 1060 via reduction gear 1040 and drive shaft 1050. The power generated by the engine 1000 is divided into two paths by the power split mechanism 1400. One is a path for driving the drive wheels 1060 via the speed reducer 1040 and the drive shaft 1050. The other is a path for generating electric power by driving MG (1) 1300.

  In such a vehicle, even when the required torques of MG (1) 1300 and MG (2) 1310 are low, if battery temperature is low (YES in S108), boost converter 800 is configured to boost the voltage. It is controlled (S110). Thus, battery 100 can be warmed up early in preparation for when the required torque of MG (1) 1300 and MG (2) 1310 increases.

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

It is a figure which shows the structure of the vehicle by which the control apparatus of the electric power supply unit which concerns on embodiment of this invention is mounted. It is a figure which shows the electric current which flows through the converter which comprises the electric power supply unit which concerns on embodiment of this invention. It is a functional block diagram of the control apparatus of the electric power supply unit which concerns on embodiment of this invention. It is a flowchart which shows the control structure of ECU which is a control apparatus of the electric power supply unit which concerns on embodiment of this invention. It is a figure which shows the electric current which flows through the battery which comprises the electric power supply unit which concerns on embodiment of this invention. It is a figure which shows the time change of the temperature of the battery which comprises the electric power supply unit which concerns on embodiment of this invention. It is a figure which shows the structure of the vehicle by which the control apparatus of the electric power supply unit which concerns on the 1st modification of embodiment of this invention is mounted. It is a figure which shows the structure of the vehicle by which the control apparatus of the electric power supply unit which concerns on the 2nd modification of embodiment of this invention is mounted.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 100 Battery, 102 Battery thermometer, 200 Inverter, 300 Motor generator, 400 Smoothing capacitor, 600 ECU, 800 Boost converter, 802 1st voltmeter, 804 2nd voltmeter, 810 1st switching element, 820 2nd switching element, 812, 822 diode, 830 reactor, 840 capacitor, 702 vehicle speed sensor, 704 accelerator opening sensor, 706 brake pedal force sensor, 1000 engine, 1300 MG (1), 1310 MG (2), 1400 power split mechanism, 1200 inverter (1 ), 1210 inverter (2), 1040 speed reducer, 1050 drive shaft, 1060 drive wheel, 2010 fuel cell.

Claims (12)

A control device for a power supply unit comprising: a secondary battery that supplies power to a load; and a converter that is provided between the load and the secondary battery and transforms and outputs an input voltage by turning on and off a switching element. There,
Means for calculating an output required for the load;
Transform determining means for determining whether or not the transformer needs to be transformed based on the required output;
Means for detecting the temperature of the secondary battery;
Temperature determining means for determining whether the temperature of the secondary battery is equal to or lower than a predetermined temperature;
When it is determined that the voltage transformation is not necessary by the voltage transformation judging means and the temperature judgment means judges that the temperature of the secondary battery is equal to or lower than a predetermined temperature, the converter is controlled to operate. And a control unit for the power supply unit. The transformer determining means includes means for determining whether or not boosting by the converter is necessary,
The control device controls the converter so as to boost the rated voltage of the secondary battery to a value corresponding to the required output when the boost determination means determines that the boost is necessary. Further comprising means for
The control device for a power supply unit according to claim 1, wherein the control means includes means for controlling the converter so as to boost the rated voltage to a predetermined value.   The control device for a power supply unit according to claim 2, wherein the predetermined value is a maximum boost value in the converter. The power supply unit further includes an inverter that is provided between the converter and the load, converts an input current, and outputs the converted current.
The controller is
Means for calculating power required from the load based on the required output;
Means for detecting the output voltage of the converter;
And a means for controlling a current converted by the inverter so that the required power is supplied to the load based on the required power and the output voltage. The control apparatus of the electric power supply unit in any one of -3. The power supply unit is mounted on a vehicle,
5. The power supply unit according to claim 1, wherein the load is a rotating electrical machine that generates driving power of the vehicle by power of the secondary battery and generates regenerative power when braking the vehicle. Control device. A control method of a power supply unit comprising: a secondary battery that supplies power to a load; and a converter that is provided between the load and the secondary battery and transforms and outputs an input voltage by turning on and off a switching element. There,
Calculating an output required for the load;
Transform determination step of determining whether or not a transform by the converter is necessary based on the required output;
Detecting the temperature of the secondary battery;
A temperature determining step of determining whether the temperature of the secondary battery is equal to or lower than a predetermined temperature;
If it is determined that the voltage transformation is not necessary in the voltage transformation determination step, and the temperature determination step determines that the temperature of the secondary battery is equal to or lower than a predetermined temperature, the converter is controlled to operate. A method for controlling the power supply unit. The transformer determining step includes a step of determining whether or not boosting by the converter is necessary,
The control method controls the converter so as to boost the rated voltage of the secondary battery to a value corresponding to the required output when it is determined that the boost is necessary in the voltage transformation determining step. Further comprising steps,
The method of controlling a power supply unit according to claim 6, wherein the control step includes a step of controlling the converter so as to boost the rated voltage to a predetermined value.   The method for controlling the power supply unit according to claim 7, wherein the predetermined value is a maximum boost value in the converter. The power supply unit further includes an inverter that is provided between the converter and the load, converts an input current, and outputs the converted current.
The control method is:
Calculating power required from the load based on the required output;
Detecting an output voltage of the converter;
The method further comprises: controlling a current converted by the inverter so that the required power is supplied to the load based on the required power and the output voltage. The control method of the electric power supply unit in any one of. The power supply unit is mounted on a vehicle,
The power supply unit according to any one of claims 6 to 9, wherein the load is a rotating electrical machine that generates driving power of the vehicle by power of the secondary battery and generates regenerative power when braking the vehicle. Control method.   The program for making a computer perform the control method in any one of Claims 6-10.   The recording medium which recorded the program for making a computer perform the control method in any one of Claims 6-10 so that computer reading was possible.

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