JP2010178515A - Battery hybrid system and method for using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To ensure the sufficiently long running distance of an electric vehicle. <P>SOLUTION: The battery hybrid system includes: a motor-driven machine, a first battery, a plurality of second batteries, an output changing section, and a controller. The controller includes: a requested power calculating processing means for calculating a requested power, a first battery output control processing means for reducing the output of a predetermined second battery so that the voltage of the predetermined second battery among the second batteries may not be lower than a threshold value in the output changing section, a necessary output calculating means for calculating an output to be required for the other second batteries based on the requested power and the output of the predetermined second battery, and a second battery output control processing means for generating an output required by the other second batteries in the output changing section. The second batteries can be used until the residual capacity becomes completely small. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a battery hybrid system and a method of using the same.

  Conventionally, an electric vehicle includes a hybrid vehicle, an electric vehicle, and the like. For example, a hybrid vehicle includes an engine and a drive motor, drives a drive motor in an urban area, and drives an engine in a suburb. Accordingly, the vehicle can be driven by driving a drive motor. The electric vehicle includes a drive motor, and is driven by driving the drive motor.

  In the electric vehicle, a rechargeable secondary battery such as a lithium ion battery is used as a power source. The drive motor is driven by receiving electric power output (powering output) from the secondary battery when accelerating the electric vehicle or causing the electric vehicle to perform steady running (constant running), and decelerates the electric vehicle. In this case, power is regenerated and input to the secondary battery (regenerative input).

  That is, the secondary battery is discharged as power is output from the secondary battery, and the secondary battery is charged as power is input to the secondary battery.

  However, in the electric vehicle having the above configuration, the cruising distance cannot be increased because the weight energy density representing the capacity per unit weight of the secondary battery is low.

  Therefore, for example, when two primary batteries with high weight energy density are connected in parallel with the secondary battery, and the remaining capacity of the secondary battery is reduced using the output of the primary battery, the power of the primary battery is reduced. It is conceivable to increase the cruising distance of the electric vehicle by supplying it to the secondary battery or supplying the electric power of the primary battery and the secondary battery to the drive motor (for example, see Patent Document 1).

JP-A-6-283210

  However, in the conventional electric vehicle, when the electric vehicle is running, the remaining capacity of the primary battery gradually decreases, and when the predetermined value is reached, the output cannot be generated, and the power of the primary battery is reduced. Cannot be supplied to the secondary battery, and the power of the primary battery and the secondary battery cannot be supplied to the drive motor. As a result, the cruising distance cannot be made sufficiently long.

  An object of the present invention is to solve the problems of the conventional electric vehicle and to provide a battery hybrid system and a method of using the same that can sufficiently increase the cruising distance of the electric vehicle.

  Therefore, in the battery hybrid system of the present invention, the electric machine, the first battery, the plurality of second batteries connected in parallel with the first battery, and the output of each second battery It has an output changing unit for controlling, and a control device.

  The control device includes: a required power calculation processing unit that calculates a required power required to drive the electric machine; and a voltage of a predetermined second battery among the second batteries in the output changing unit. On the basis of the first battery output control processing means for reducing the output of the predetermined second battery, the required power, and the output of the predetermined second battery so that the voltage does not become lower than a threshold value. The required output calculation processing means for calculating the output required for the other second battery, and the second battery for generating the required output by the other second battery in the output changing unit. Output control processing means is provided.

  In another battery hybrid system of the present invention, the control device further includes an output determination processing means for determining whether or not the output of the predetermined second battery is smaller than a threshold, and the predetermined second battery. When the output is smaller than the threshold value, battery use processing means for ending use of the predetermined second battery is provided.

  In still another battery hybrid system of the present invention, the output changing unit further includes a switching element for controlling the output of each second battery.

  The first battery output control processing means corresponds to the voltage difference between the threshold and the voltage of the predetermined second battery when the voltage of the predetermined second battery is lower than the threshold. The duty ratio of the switching element for controlling the output of the second battery is changed.

  In still another battery hybrid system of the present invention, the output changing unit further includes a switching element for controlling the output of each second battery.

  The first battery output control processing means is configured to control the duty of a switching element for controlling the output of the predetermined second battery in correspondence with the output difference calculated based on the change amount of the required power. Change the ratio.

  In still another battery hybrid system of the present invention, the output changing unit further includes a switching element for controlling the output of each second battery.

  Then, the second battery output control processing means switches for controlling the output of the other second battery in correspondence with the output difference calculated based on the required output change amount. Change the duty ratio of the element.

  In still another battery hybrid system of the present invention, the output changing unit further includes a switching element for controlling the output of each second battery.

  The second battery output control processing means controls the output of the other second battery in correspondence with the output difference and the voltage difference calculated based on the required output change amount. To change the duty ratio of the switching element.

  In still another battery hybrid system of the present invention, the control device further includes battery information acquisition processing means for acquiring a remaining capacity of each of the second batteries.

  The first battery output control processing means reduces the output of the predetermined second battery so that the voltage of the second battery having the smallest remaining capacity does not become lower than the threshold value.

  In the method of using the battery hybrid system of the present invention, the electric machine, the first battery, the plurality of second batteries connected in parallel with the first battery, and the output of each second battery are controlled. This is applied to a battery hybrid system having an output changing unit and a control device.

  Then, the required power required to drive the electric machine is calculated, and the predetermined voltage of the second battery among the second batteries is not reduced below a threshold value in the output changing unit. The output of the second battery is reduced, and the output required for the other second battery is calculated based on the required power and the output of the predetermined second battery. The required output is generated by the other second battery.

  According to the present invention, in the battery hybrid system, the electric machine, the first battery, the plurality of second batteries connected in parallel with the first battery, and the output of each second battery It has an output changing unit for controlling, and a control device.

  The control device includes a required power calculation processing unit that calculates a required power required to drive the electric machine, and a voltage of a predetermined second battery among the second batteries in the output changing unit. Based on the first battery output control processing means for reducing the output of the predetermined second battery, the required power, and the output of the predetermined second battery so that the output of the predetermined second battery is not lower than the threshold. Required output calculation processing means for calculating the output required for the battery, and second battery output control processing means for generating the required output by the other second battery in the output changing unit. Prepare.

  In this case, since the output of the predetermined second battery is reduced in the output changing unit so that the voltage of the predetermined second battery does not become lower than the threshold value, the second battery is operated until the remaining capacity becomes sufficiently small. Can be used. Therefore, the cruising distance of the electric vehicle can be made sufficiently long.

  Moreover, since the required output is generated by the other second battery, a sufficient torque can be generated by the electric machine.

  In another battery hybrid system of the present invention, the control device further includes an output determination processing means for determining whether or not the output of the predetermined second battery is smaller than a threshold, and the predetermined second battery. Battery use processing means for terminating the use of the predetermined second battery when the output is smaller than the threshold value.

  In this case, when the output of the second battery becomes smaller than the threshold value, the use of the second battery is terminated. Therefore, the use of the second battery is continued until the remaining capacity becomes sufficiently small. Can do.

It is a figure which shows the battery hybrid system in embodiment of this invention. It is a flowchart which shows operation | movement of the inverter control part in embodiment of this invention. It is a 1st flowchart which shows operation | movement of the battery hybrid system in embodiment of this invention. It is a 2nd flowchart which shows operation | movement of the battery hybrid system in embodiment of this invention. It is a figure which shows the subroutine of the 1st primary battery output control process in embodiment of this invention. It is explanatory drawing which shows operation | movement of the 1st primary battery output control process means in embodiment of this invention. It is a figure which shows the subroutine of the 2nd primary battery output control process in embodiment of this invention. It is a conceptual diagram in the case of using the 1st, 2nd primary battery in embodiment of this invention alternately.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a battery hybrid system according to an embodiment of the present invention.

  In the figure, 10 is a booster circuit control unit as a control device and as a first control unit, 11 is a drive motor as an electric machine, 13 is a load connected to the drive motor 11 and current. An inverter as a conversion unit, 14 is a power supply unit connected to the inverter 13, and 90 is an inverter control unit as a second control unit that controls the inverter 13 to drive the drive motor 11. In the present embodiment, the inverter control unit 90 is built in the inverter 13, but may be arranged independently of the inverter 13.

  The drive motor 11 is mechanically connected to a drive wheel (not shown) via an output shaft (not shown), and is driven by power supplied from the power supply unit 14 via the inverter 13 during power running. Then, a drive motor torque is generated and transmitted to the drive wheel, and electric power is regenerated by receiving rotation from the drive wheel during regeneration, and is supplied to the power supply unit 14 via the inverter 13.

  The inverter 13 includes a DC / DC converter (not shown) as a voltage conversion unit and a plurality of transistors (not shown) as, for example, six switching elements. The DC / DC converter outputs the output voltage of the power supply unit 14. The voltage is changed to a predetermined voltage, and each of the transistors is united to form a transistor module (IGBT) of each phase, and is turned on / off by a drive signal sent from the booster circuit control unit 10, and a power supply unit The direct current supplied from 14 is converted into a three-phase alternating current and supplied to the drive motor 11. In this embodiment, the DC / DC converter is built in the inverter 13, but can be arranged independently of the inverter 13.

  The power supply unit 14 includes a plurality of the present embodiments as a rechargeable first battery, a secondary battery 15 as a main battery, a second battery that cannot be recharged, and as an auxiliary battery. In the embodiment, the first and second primary batteries 16a and 16b, and the output changing unit for changing the voltages Vsa and Vsb of the first and second primary batteries 16a and 16b, and the voltage The booster circuit 18 is provided as a changing unit, and the secondary battery 15, the first and second primary batteries 16 a and 16 b, and the booster circuit 18 are connected to each other and in parallel to the inverter 13. The booster circuit controller 10 reads the remaining capacity SOCm of the secondary battery 15 as the first battery information, and the remaining capacities SOCsa and SOCsb of the first and second primary batteries 16a and 16b as the second battery information. . The remaining capacities SOCm, SOCsa, and SOCsb represent the amount of electricity charged with respect to the capacities (battery capacities) of the secondary battery 15 and the first and second primary batteries 16a and 16b in percentage. Further, the booster circuit control unit 10 reads the accelerator opening α as an acceleration index detected by an accelerator opening sensor as an acceleration index detection unit disposed on an accelerator pedal (not shown).

  A battery hybrid system includes the booster circuit control unit 10, the drive motor 11, the inverter 13, the power supply unit 14, the secondary battery 15, the first and second primary batteries 16a and 16b, the booster circuit 18, the inverter control unit 90, and the like. Is configured.

  In the present embodiment, the secondary battery 15 is an energy density, and in the present embodiment, a battery having a low weight energy density and a high output density, such as a lithium ion battery, is used. As the primary batteries 16a and 16b, batteries having a low output density and a high weight energy density, for example, air batteries are used.

  In the present embodiment, the secondary battery 15 is used as the first battery and as the main battery, but the first and second primary batteries are replaced with the secondary battery 15. A primary battery different from 16a and 16b can be used. In the present embodiment, the first and second primary batteries 16a and 16b are used as the second battery and as the auxiliary battery. Instead of 16a and 16b, a secondary battery different from the secondary battery 15 or the same secondary battery having different capacities can be used.

  The first and second primary batteries 16a and 16b are small in size and light in weight because of high weight energy density, and are detachably disposed on the main body of the electric vehicle, that is, the vehicle main body. In addition, the output density of the first and second primary batteries 16a and 16b is lower than that of the secondary battery 15. Therefore, when a large amount of power is required, the secondary battery 15 or the first and second primary batteries 16a and 16b output density. It is desirable to supply power from the primary batteries 16a and 16b and the secondary battery 15.

  The vehicle main body is provided with a proximity switch (not shown) as a battery detection unit, and it is determined whether the first and second primary batteries 16a and 16b are set in the vehicle main body based on the sensor output of the proximity switch. can do. In an air battery, air is used for the positive electrode and metal such as aluminum or zinc is used for the negative electrode, and electric power is generated by causing a chemical reaction between oxygen and metal in the air.

  In the present embodiment, the inverter 13 and the booster circuit 18 are disposed independently, and the secondary battery 15 or the first and second primary batteries 16a and 16b and the booster circuit 18 are disposed independently. However, the inverter 13 and the booster circuit 18 are integrated to form an inverter unit, the secondary battery 15 and the booster circuit 18 are integrated to form a secondary battery unit, the first and second primary The batteries 16a and 16b and the booster circuit 18 may be integrated to form a primary battery unit.

  Further, the booster circuit 18 receives a PWM command as an output change drive signal from the booster circuit control unit 10, changes the voltages Vsa and Vsb, and applies the changed voltages to the inverter 13 as output voltages. In this case, the booster circuit 18 can not only increase (boost) the voltages Vsa and Vsb, but also function as a step-down circuit to decrease (decrease) the voltages Vsa and Vsb.

  For this purpose, the booster circuit 18 corresponds to the first primary battery 16a, the coil La, the diode Da, and the field-effect transistor Tra as a switching element corresponding to the second primary battery 16b, and the coil Lb, the diode. In addition to Db and a field effect transistor Trb as a switching element, a capacitor C common to the first and second primary batteries 16a and 16b is provided. In the present embodiment, the first and second primary batteries 16a and 16b are provided with a common capacitor C. However, capacitors can be provided respectively.

  The coil La and the diode Da are arranged in series between the positive-side terminals of the secondary battery 15 and the first primary battery 16a, and one end of the coil La and the positive-side terminal of the primary battery 16a However, the other end of the coil La and the anode of the diode Da are connected to the cathode of the diode Da and the terminal on the positive side of the secondary battery 15. The field effect transistor Tra is disposed between a connection portion pa1 between the other end of the coil La and the anode of the diode Da and the ground GND, and the drain of the field effect transistor Tra and the connection portion pa1. However, the source of the field effect transistor Tra and the ground GND are connected, and the gate of the field effect transistor Tra and the booster circuit control unit 10 are connected. Further, the capacitor C is disposed between the connection portion pa3 between the cathode of the diode Da and the positive terminal of the secondary battery 15 and the ground GND, and one end of the capacitor C and the connection portion pa3 are provided. The other end of the capacitor C and the ground GND are connected.

  In addition, the coil Lb and the diode Db are arranged in series between the positive-side terminals of the secondary battery 15 and the second primary battery 16b, and one end of the coil Lb and the positive-side terminal of the primary battery 16b However, the other end of the coil Lb and the anode of the diode Db are connected to the cathode of the diode Db and the positive electrode side terminal of the secondary battery 15. The field effect transistor Trb is disposed between a connection portion pb1 between the other end of the coil Lb and the anode of the diode Db and the ground GND, and the drain of the field effect transistor Trb and the connection portion pb1 However, the source of the field effect transistor Trb and the ground GND are connected, and the gate of the field effect transistor Trb and the booster circuit control unit 10 are connected.

  A current sensor 22a (A) as a current detector is connected in series with the first primary battery 16a, and a voltage sensor 23a (V) as a voltage detector is connected in parallel with the first primary battery 16a. The sensor 22a detects the current of the first primary battery 16a as the third battery information, that is, the current Isa flowing through the coil La, and the voltage sensor 23a detects the first primary battery 16a as the fourth battery information. The voltage Vsa is detected. In addition, a current sensor 22b (A) as a current detector is connected in series with the second primary battery 16b, and a voltage sensor 23b (V) as a voltage detector is connected in parallel with the second primary battery 16b. The sensor 22b detects the current of the second primary battery 16b as the fifth battery information, that is, the current Isb flowing through the coil Lb, and the voltage sensor 23b detects the second primary battery 16b as the sixth battery information. The voltage Vsb is detected. Furthermore, a current sensor 24 (A) as a current detection unit is connected in series with the secondary battery 15, and a voltage sensor 25 (V) as a voltage detection unit is connected in parallel with the secondary battery 15. The current Im of the secondary battery 15 as the seventh battery information is detected, and the voltage Vm of the secondary battery 15 as the eighth battery information is detected by the voltage sensor 25. Then, a current sensor 26 (A) as a current detection unit is connected in series with the inverter 13, and a voltage sensor 27 (V) as a voltage detection unit is connected in parallel with the inverter 13. The current input to the inverter 13 as information, that is, the inverter current Ii is detected, and the voltage input to the inverter 13 as the tenth battery information, that is, the inverter voltage Vi is detected by the voltage sensor 27.

  By the way, when the booster circuit control unit 10 calculates a duty ratio for switching the field effect transistors Tra and Trb, the boost circuit control unit 10 calculates a PWM command based on the duty ratio and applies the PWM command to the gates of the field effect transistors Tra and Trb. send.

  When the field effect transistors Tra and Trb are turned on, current flows through the coils La and Lb. When the field effect transistors Tra and Trb are turned off, current does not flow through the coils La and Lb. A high voltage is generated at the cathodes of the diodes Da and Db so as to prevent this change. When switching of the field effect transistors Tra and Trb, that is, on / off is repeated, a high voltage is repeatedly generated on the cathode side of the diodes Da and Db, and the high voltage is smoothed by the capacitor C. A higher output voltage is generated at the output terminal tm1 as the switching duty ratio is higher and as the duty ratio is lower.

  Next, the operation of the inverter control unit 90 when driving the drive motor 11 will be described.

  FIG. 2 is a flowchart showing the operation of the inverter control unit in the embodiment of the present invention.

  First, information acquisition processing means (not shown) of the inverter control unit 90 performs information acquisition processing and reads the accelerator opening α. Next, vehicle request torque calculation processing means (not shown) of the inverter control unit 90 performs vehicle request torque calculation processing, reads the magnetic pole position θM of the drive motor 11 detected by a position detection unit such as a resolver (not shown), and the magnetic pole A vehicle speed v is calculated based on the position θM. The vehicle required torque calculation processing means calculates the vehicle required torque based on the vehicle speed v and the accelerator opening α.

  Subsequently, a current command value calculation processing unit (not shown) of the inverter control unit 90 performs a current command value calculation process, reads the inverter voltage Vi detected by the voltage sensor 27, and calculates it based on the magnetic pole position θM. The rotation speed of the drive motor 11, that is, the drive motor rotation speed NM is read, and a current command value is calculated based on the inverter voltage Vi and the drive motor rotation speed NM.

  Then, an IGBT control processing unit (not shown) of the inverter control unit 90 performs an IGBT control process and drives the inverter 13 based on the current command value. As a result, the drive motor 11 is supplied with three-phase currents of U phase, V phase, and W phase, and the drive motor 11 is driven.

Next, a flowchart will be described.
Step S1: The accelerator opening α is read.
Step S2 Calculate the vehicle required torque.
Step S3 Read the inverter voltage Vi.
Step S4 Read the drive motor rotational speed NM.
Step S5: Calculate a current command value.
Step S6: The IGBT control process is performed and the process is terminated.

  Next, one of the first and second primary batteries 16a, 16b is used to increase the cruising distance of the electric vehicle, and the other primary battery is required to run the electric vehicle. The operation of the battery hybrid system when used to generate a large drive motor torque will be described.

  In the present embodiment, in order to increase the cruising distance of the first primary battery 16a as a predetermined second battery, the second primary battery 16b as another second battery is used. Use to generate the drive motor torque, use the first primary battery 16a to generate the drive motor torque, use the second primary battery 16b to increase the cruising distance of the electric vehicle, Can be done. Therefore, for example, when the first primary battery 16a is used to increase the cruising distance of the electric vehicle, the remaining capacity SOCsa is reduced, and the first primary battery 16a cannot be used, the first primary battery 16a is used. The battery 16a is replaced with a new one, and then the second primary battery 16b is used to increase the cruising range of the electric vehicle.

  In the present embodiment, a case will be described in which the first primary battery 16a is used to generate drive motor torque in order to increase the cruising distance of the electric vehicle.

  3 is a first flowchart showing the operation of the battery hybrid system according to the embodiment of the present invention, FIG. 4 is a second flowchart showing the operation of the battery hybrid system according to the embodiment of the present invention, and FIG. The figure which shows the subroutine of the 1st primary battery output control processing in embodiment, FIG. 6 is explanatory drawing which shows operation | movement of the 1st primary battery output control processing means in embodiment of this invention, FIG. The figure which shows the subroutine of the 2nd primary battery output control process in embodiment, FIG. 8 is a conceptual diagram in the case of using the 1st and 2nd primary battery in embodiment of this invention alternately. In FIG. 6, the horizontal axis represents current Isa and the vertical axis represents output Wsa.

  First, battery information acquisition processing means (not shown) of the booster circuit control unit 10 performs battery information acquisition processing and acquires the remaining capacity SOCm of the secondary battery 15 by reading it.

  Subsequently, a first battery use processing unit (not shown) of the booster circuit control unit 10 performs a first battery use process and starts using the secondary battery 15. Then, the remaining capacity determination processing means (not shown) of the booster circuit control unit 10 performs the remaining capacity determination process. As the secondary battery 15 is used, the remaining capacity SOCm is a lower limit SOCL as a threshold value, this embodiment. In the case, it is determined whether or not it has become smaller than 30 [%].

  When the remaining capacity SOCm becomes smaller than 30 [%], the battery information acquisition processing unit reads the voltage Vsa and current Isa of the first primary battery 16a and the voltage Vsb and current Isb of the second primary battery 16b. The second battery usage processing unit (not shown) of the booster circuit control unit 10 performs the second battery usage processing and starts using the first primary battery 16a.

Subsequently, an output calculation processing unit (not shown) of the booster circuit control unit 10 performs an output calculation process, and based on the voltage Vsa and the current Isa, the output Wsa of the first primary battery 16a.
Wsa = Vsa · Isa
And the output Wsb of the second primary battery 16b based on the voltage Vsb and the current Isb.
Wsb = Vsb · Isb
Is calculated.

  In addition, a target output calculation processing unit (not shown) of the booster circuit control unit 10 performs a target output calculation process to calculate a target output Wsr that represents a target value of the overall output of the first and second primary batteries 16a and 16b. To do.

  Therefore, an inverter required power acquisition processing unit (not shown) as a required power acquisition processing unit (not shown) of the booster circuit control unit 10 performs an inverter required power acquisition process as a required power acquisition process and is necessary for driving the drive motor 11. The inverter required power Wi as the required power is obtained by reading from the inverter control unit 90.

For that purpose, the inverter required power calculation processing means as the required power calculation processing means (not shown) of the inverter control unit 90 performs the inverter required power calculation processing as the required power calculation processing, reads the inverter voltage Vi and the inverter current Ii, The inverter required power Wi
Wi = Vi · Ii
Is calculated. In the present embodiment, the inverter required power Wi is calculated in the inverter control unit 90, but the inverter required power Wi can be calculated in the boost circuit control unit 10.

  Then, the target output calculation processing means calculates a moving average value of the inverter required power Wi (an average value of the inverter required power Wi calculated over time), and the moving average value is set as the target output Wsr. To do.

  Subsequently, a battery operation determination processing unit (not shown) of the booster circuit control unit 10 performs a battery operation determination process, reads the sensor output of the proximity switch, and determines whether the second primary battery 16b is set in the vehicle body. To determine whether the second primary battery 16b exists.

  When the second primary battery 16b is not set in the vehicle main body and the second primary battery 16b does not exist, the first primary battery output control processing means (not shown) of the booster circuit control unit 10 is not shown. The battery output control processing means performs a first primary battery output control process as a first battery output control process, and generates an output Wsa by the first primary battery 16a.

  When the second primary battery 16b is set in the vehicle body and the second primary battery 16b is present, the battery operation determination processing means causes the second primary battery 16b to generate the output Wsb. Whether or not the second primary battery 16b is used is determined depending on whether or not the battery is used.

When the second primary battery 16b does not generate the output Wsb and is not used, a battery use necessity determination processing unit (not shown) of the booster circuit control unit 10 performs a battery use necessity determination process, It is determined whether the output Wsa is insufficient, that is, whether it is necessary to use not only the first primary battery 16a but also the second primary battery 16b. For this purpose, the required output calculation processing means (not shown) of the booster circuit control unit 10 performs the required output calculation processing, and subtracts the output Wsa from the target output Wsr to obtain the required output Wsbr.
Wsbr = Wsr-Wsa
Is calculated. Then, the battery use necessity determination processing means reads the required output Wsbr, and when the required output Wsbr is larger than the threshold value Wth, determines that the second primary battery 16b needs to be used together, and the required output Wsbr. Is less than or equal to the threshold value Wth, it is determined that it is not necessary to use the second primary battery 16b together.

  When it is necessary to use the second primary battery 16b together, the second battery use processing means starts using the second primary battery 16b. The first primary battery output control processing means controls the output Wsa, and the second primary battery output control processing means as the second battery output control processing means (not shown) of the booster circuit control unit 10 is the second The second primary battery output control process as the battery output control process is performed to control the output Wsb.

  When the second primary battery 16b generates the output Wsb and is used, the first primary battery output control processing means controls the output Wsa, and the second primary battery output control processing means. Controls the output Wsb.

Next, the flowcharts of FIGS. 3 and 4 will be described.
Step S11: Read the remaining capacity SOCm of the secondary battery 15.
Step S12: It is determined whether the remaining capacity SOCm is smaller than 30 [%]. When the remaining capacity SOCm is smaller than 30 [%], the process proceeds to step S13, and when it is 30 [%] or more, the process returns to step S11.
Step S13: The voltage Vsa of the first primary battery 16a is read.
Step S14: Read the current Isa of the first primary battery 16a.
Step S15: The voltage Vsb of the second primary battery 16b is read.
Step S16: Read the current Isb of the second primary battery 16b.
Step S17: The output Wsa of the first primary battery 16a is calculated.
Step S18: The output Wsb of the second primary battery 16b is calculated.
Step S19: Read the target output Wsr of the primary battery.
Step S20: It is determined whether the second primary battery 16b is present. If the second primary battery 16b is present, the process proceeds to step S21, and if not, the process proceeds to step S27.
Step S21: It is determined whether the second primary battery 16b is used. If the second primary battery 16b is used, the process proceeds to step S25. If the second primary battery 16b is not used, the process proceeds to step S22.
Step S22: A shortage output is calculated.
Step S23: It is determined whether the required output Wsbr is larger than the threshold value Wth. When the required output Wsbr is larger than the threshold value Wth, the process proceeds to step S24, and when it is less than the threshold value Wth, the process proceeds to step S27.
Step S24: Use of the second primary battery 16b is started.
Step S25: A first primary battery output control process is performed.
Step S26: A second primary battery output control process is performed, and the process ends.
Step S27: The first primary battery output control process is performed and the process is terminated.

  Next, the operation of the first primary battery output control processing means will be described.

  In this case, the first primary battery output control processing means adjusts the duty ratio for switching the field effect transistor Tra in the booster circuit 18 so that the voltage Vsa does not become lower than the lower limit voltage VsL as a preset threshold value. Then, the output Wsa is controlled.

  A switch (not shown) is provided between the secondary battery 15 and the first and second primary batteries 16a and 16b, for example, between the first and second primary batteries 16a and 16b and the coils La and Lb. Arranged. When the use of the first and second primary batteries 16a and 16b is started, if the voltages Vsa and Vsb are higher than the voltage Vm, the switch is turned on and the first and second secondary batteries 15 are turned on. Electric power is supplied from the first and second primary batteries 16a and 16b to the secondary battery 15 simply by connecting the primary batteries 16a and 16b. On the other hand, when the voltages Vsa and Vsb are lower than the voltage Vm, the first and second primary batteries 16a and 16b are simply connected by turning on the switch and connecting the first and second primary batteries 16a and 16b. There is no supply of power from the second primary batteries 16a and 16b to the secondary battery 15, and when the voltages Vsa and Vsb are made higher than the voltage Vm by the booster circuit 18, the first and second primary batteries 16a, Power is supplied to the secondary battery 15 from 16b.

  By the way, as shown in FIG. 6, the first primary battery 16a is used at the point A (remaining capacity SOCsa is 100%, the output Wsa is the value Ws1, and the current Isa is the value Is1. When the drive motor 11 is driven to drive the electric vehicle, the remaining capacity SOCsa gradually decreases. At this time, if the output Wsa is maintained at the value Ws1, it is necessary to flow as much current Isa as the voltage Vsa becomes low, and the value of the current Isa gradually increases.

  When the remaining capacity SOCsa reaches 30% in the state of the point B ′, the output Wsa cannot be maintained at the value Ws1 thereafter. Therefore, it becomes impossible to use the first primary battery 16a when the remaining capacity SOCsa is 30%.

  Therefore, in the present embodiment, after the use of the first primary battery 16a is started at the state of point A, the output Wsa is reduced as the remaining capacity SOCsa decreases, and the remaining capacity SOCsa is reduced to 30 [%. The state B is formed when the remaining capacity SOCsa becomes 10%. That is, as the remaining capacity SOCsa decreases, the value of the output Wsa in the power supply unit 14 is decreased. Therefore, the remaining capacity SOCsa is the minimum value that can be theoretically used, which is 0% in the present embodiment. Until then, the first primary battery 16a can continue to be used. During this time, the voltage Vsa of the first primary battery 16a is set so as not to be lower than the lower limit voltage VsL.

  Therefore, in the present embodiment, the output determination processing means of the first primary battery output control processing means performs output determination processing, and determines whether or not the output Wsa is smaller than a lower limit output WsL as a preset threshold value. to decide. When the output Wsa is smaller than the lower limit output WsL, the battery usage processing means of the first primary battery output control processing means performs battery usage processing and ends the use of the first primary battery 16a. Then, the notification processing means of the first primary battery output control processing means performs notification processing, and it is not shown that the use of the first primary battery 16a is terminated on the instrument panel of the electric vehicle. The information is displayed on the display unit and notified to the driver who is the operator.

  When the output Wsa is equal to or higher than the lower limit output WsL, the field effect transistor Tra is set so that the voltage Vsa does not become lower than the lower limit voltage VsL as the remaining capacity SOCsa of the first primary battery 16a decreases. The duty ratio Dutya for switching is adjusted.

For this purpose, the voltage determination processing means of the first primary battery output control processing means performs voltage determination processing to determine whether or not the voltage Vsa is equal to or lower than the lower limit voltage VsL. When the voltage Vsa is equal to or lower than the lower limit voltage VsL, the voltage difference calculation processing means of the first primary battery output control processing means performs a voltage difference calculation process, and a voltage difference δVsa between the lower limit voltage VsL and the voltage Vsa.
δVsa = VsL−Vsa
The duty ratio calculation processing means as an output change processing means of the first primary battery output control processing means performs a duty ratio calculation process as an output change process, and corresponds to the voltage difference δVsa to generate an electric field. The duty ratio Dutya for switching the effect transistor Tra is changed and reduced. When the value of the duty ratio Dutya after being reduced is Duty 'and the proportionality constant is k1, the value Duty' is
Dutya == Dutya-k1 · δVsa
To be. Therefore, the output Wsa of the first primary battery 16a can be reduced.

When the voltage Vsa is higher than the lower limit voltage VsL, the output difference calculation processing means of the first primary battery output control processing means performs an output difference calculation process, and the previous value from the current value Wsr (n) of the target output Wsr. Output difference δWs representing a value obtained by subtracting Wsr (n−1) and dividing by 2
δWs = (Wsr (n) −Wsr (n−1)) / 2
The duty ratio calculation processing means reads the output difference δWs and changes the duty ratio Dutya. When the changed duty ratio Dutya is Duty 'and the proportionality constant is k2, the value Duty' is
Dutya '= Dutya + k2 · δWs
To be. Therefore, the output Wsa of the first primary battery 16a can be increased.

Next, the flowchart of FIG. 5 will be described.
Step S25-1: It is determined whether or not the output Wsa is smaller than the lower limit output WsL. If the output Wsa is smaller than the lower limit output WsL, the process proceeds to step S25-5. If the output Wsa is greater than or equal to the lower limit output WsL, the process proceeds to step S25-2.
Step S25-2: It is determined whether or not the voltage Vsa is lower than the lower limit voltage VsL. If the voltage Vsa is equal to or lower than the lower limit voltage VsL, the process proceeds to step S25-3. If the voltage Vsa is higher than the lower limit voltage VsL, the process proceeds to step S25-7.
Step S25-3: A value obtained by subtracting the voltage Vsa from the lower limit voltage VsL is set to a voltage difference δVsa.
Step S25-4: The value obtained by subtracting the value k1 · δVsa from the duty ratio Duty is set to the duty ratio Dutya, and the process returns.
Step S25-5: Use of the first primary battery 16a is terminated.
Step S25-6: Performs notification processing and returns.
Step S25-7 The previous value Wsr (n-1) is subtracted from the current value Wsr (n) of the target output Wsr, and the value divided by 2 is set as the output difference δWs.
Step S22-8: The value obtained by adding the value k2 · δWs to the duty ratio Duty is set to the duty ratio Dutya, and the process returns.

  Next, the operation of the second primary battery output control processing means will be described.

  In this case, the second primary battery output control processing means adjusts the duty ratio for switching the field effect transistor Trb in the booster circuit 18 to generate the required output Wsbr, and the second primary battery 16b The output Wsb is controlled.

For this purpose, the output difference calculation processing means of the second primary battery output control processing means performs output difference calculation processing, and the current value Wsbr (n) of the required output Wsbr to the previous value Wsbr (n−1). The output difference δWsb by subtracting
δWsb = Wsbr (n) −Wsbr (n−1)
And duty ratio calculation processing means as output change processing means of the second primary battery output control processing means performs duty ratio calculation processing as output change processing, reads the voltage difference δVsa and output difference δWsb, The duty ratio Dutyb is changed. When the changed duty ratio Dutyb is Dutyb ′ and the proportionality constants are k3 and k4, the value Dutyb ′ is
Dutyb ′ = Dutyb + k3 · δVsa−k4 · δWsb
To be. Therefore, the output Wsb of the second primary battery 16b can be changed according to the output Wsa of the first primary battery 16a.

Next, the flowchart of FIG. 7 will be described.
Step S26-1: A value obtained by subtracting the previous value Wsbr (n-1) from the current value Wsbr (n) of the required output Wsbr is set as the output difference δWsb.
Step S26-2: The value obtained by subtracting the value k4 · δWsb from the value obtained by adding the value k3 · δVsa to the duty ratio Dutyb is set to the duty ratio Dutyb, and the process returns.

  Thus, in the present embodiment, when the remaining capacity SOCm of the secondary battery 15 decreases, one of the first and second primary batteries 16a and 16b, in this case, the first primary battery. When the duty ratio Dutya is gradually reduced so that the voltage Vsa of 16a does not become lower than the lower limit voltage VsL, the use of the first primary battery 16a is continued, and the first primary battery 16a cannot be used. 8, the first primary battery 16a is replaced with a new one, and the second primary battery 16b is used. Therefore, the remaining capacity SOCsa of the first and second primary batteries 16a, 16b, The first and second primary batteries 16a and 16b can be used until the SOCsb becomes sufficiently small. Therefore, the cruising distance of the electric vehicle can be made sufficiently long.

  In FIG. 8, Ai (i = 1, 2,...) Represents a change in the output Wsa of the first primary battery 16a, and Bi (i = 1, 2,...) Represents an output Wsb of the second primary battery 16b. Represents changes.

  In addition, since the required output Wsbr is generated by one of the first and second primary batteries 16a and 16b, in this case, the second primary battery 16b, the drive motor 11 can provide a sufficient drive motor torque. Can be generated.

  In the present embodiment, when the remaining capacity SOCm of the secondary battery 15 decreases, one of the first and second primary batteries 16a and 16b, in this case, the voltage Vsa of the first primary battery 16a. When the first primary battery 16a cannot be used while the first primary battery 16a cannot be used while the duty ratio Dutya is gradually reduced so that the first primary battery 16a cannot be used. The battery 16a is replaced with a new one, and the second primary battery 16b is used, but the primary battery having a small remaining capacity SOCsa or SOCsb among the first and second primary batteries 16a and 16b. It is also possible to continue using the primary battery while gradually reducing the duty ratio so that the voltage does not become lower than the lower limit voltage VsL.

  In this case, the battery information acquisition processing unit acquires the remaining capacity SOCsa and SOCsb by reading, and the first battery output control processing unit prevents the voltage of the primary battery having the smallest remaining capacity from becoming lower than the threshold value VsL. In addition, the output of the primary battery is reduced.

  In addition, this invention is not limited to the said embodiment, It can change variously based on the meaning of this invention, and does not exclude them from the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 Booster circuit control part 11 Drive motor 14 Power supply part 15 Secondary battery 16a, 16b 1st, 2nd primary battery 18 Booster circuit 90 Inverter control part Dutya, Dutyb Duty ratio Tra, Trb Field effect transistor Vsa, Vsb Voltage VsL Lower limit Voltage Wsa Output Wi Inverter required power Wsbr Required output δVsa Voltage difference δWs, δWsb Output difference

Claims (8)

  An electric machine, a first battery, a plurality of second batteries connected in parallel with the first battery, an output changing unit for controlling the output of each second battery, and a control device; And the control device includes a required power calculation processing means for calculating a required power required to drive the electric machine, and a predetermined second battery among the second batteries in the output changing unit. The first battery output control processing means for reducing the output of the predetermined second battery, the required power, and the output of the predetermined second battery, so that the voltage of Necessary output calculation processing means for calculating an output required for the second battery, and a second battery output control process for generating the required output by the other second battery in the output changing unit. Battery high characterized by comprising means Lid system.   The control device is configured to determine whether or not the output of the predetermined second battery is smaller than a threshold, and when the output of the predetermined second battery is smaller than the threshold, the predetermined second battery The battery hybrid system according to claim 1, further comprising battery use processing means for terminating use of the battery.   The output changing unit includes a switching element for controlling the output of each second battery, and the first battery output control processing means has a threshold value when the voltage of the predetermined second battery is lower than the threshold value. 2. The battery hybrid system according to claim 1, wherein a duty ratio of a switching element for controlling an output of the predetermined second battery is changed in accordance with a voltage difference between the voltage of the second battery and a predetermined second battery.   The output changing unit includes a switching element for controlling the output of each second battery, and the first battery output control processing means is made to correspond to the output difference calculated based on the change amount of the required power. The battery hybrid system according to claim 1, wherein a duty ratio of a switching element for controlling an output of the predetermined second battery is changed.   The output changing unit includes a switching element for controlling the output of each second battery, and the second battery output control processing means calculates an output difference calculated based on the required output change amount. 2. The battery hybrid system according to claim 1, wherein a duty ratio of a switching element for controlling an output of the other second battery is changed in accordance with.   The output changing unit includes a switching element for controlling the output of each second battery, and the second battery output control processing means calculates an output difference calculated based on the required output change amount. The battery hybrid system according to claim 5, wherein a duty ratio of a switching element for controlling an output of the other second battery is changed in accordance with the voltage difference.   The control device includes battery information acquisition processing means for acquiring the remaining capacity of each of the second batteries, and the first battery output control processing means is configured such that the voltage of the second battery having the smallest remaining capacity is a threshold value. The battery hybrid system according to claim 1 or 3, wherein an output of the predetermined second battery is reduced so as not to lower.   A battery hybrid having an electric machine, a first battery, a plurality of second batteries connected in parallel with the first battery, an output changing unit for controlling the output of each second battery, and a control device In the method of using the system, the required power required to drive the electric machine is calculated, and the output changing unit prevents the voltage of a predetermined second battery among the second batteries from becoming lower than a threshold value. The output of the predetermined second battery is reduced, the output required for another second battery is calculated based on the required power and the output of the predetermined second battery, and the output The changing unit generates the required output by the other second battery, and uses the battery hybrid system.

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