JP2018057179A - Power supply system, and battery unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply system in which a power supply failure in a constant voltage requiring load can be suppressed while input of high power from a rotary electric machine to a booster circuit is suppressed.SOLUTION: The power supply system is provided, comprising a rotary electric machine 17 having a function as a power generator and a lead storage battery 11 and lithium-ion storage battery 12. The power supply system also comprises: a first line L1 for connecting a first connection point N1 to which the lead storage battery 11 is connected with a second connection point N2 to which the lithium-ion storage battery 12 is connected; and a second line L2 for connecting the second connection point with a third connection point N3 to which the rotary electric machine 17 is connected. The power supply system further comprises: a first switch 21 for switching conduction/interception of the first line L1; a second switch 22 for switching conduction/interception of the first line L2; and a booster circuit 24 connected in parallel to the first switch SW1, the booster circuit outputting voltage obtained by boosting a voltage input from the lithium-ion storage battery 12.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power supply system and a battery unit including a rotating electrical machine having a function as a generator, and a first storage battery and a second storage battery connected in parallel to the rotating electrical machine.

  A power supply system including two storage batteries (a first storage battery and a second storage battery) and a rotating electrical machine having a function as a generator is known (for example, Patent Document 1). In the power supply system, power efficiency is improved by appropriately using the first storage battery and the second storage battery.

Japanese Patent No. 5387383

  In a power supply system including the first storage battery and the second storage battery, and the rotating electrical machine, a connection point to which the first storage battery is connected is a first connection point, and a connection point to which the second storage battery is connected is a second connection point, A connection point to which the rotating electrical machine is connected is defined as a third connection point. Of the three paths, a path connecting the first connection point and the second connection point, a path connecting the first connection point and the third connection point, and a path connecting the second connection point and the third connection point. A configuration in which only two routes are provided as the first route and the second route can be considered. Further, a first switch and a second switch are provided for the first route and the second route, respectively. In this configuration, when power generation is performed in the rotating electrical machine, the opening / closing control is appropriately performed on the first switch and the second switch, so that the rotating electrical machine is controlled according to the state of the first storage battery and the second storage battery. Therefore, the first storage battery and the second storage battery can be selectively charged.

  Here, in addition to the first storage battery, the second storage battery, and the rotating electrical machine, a constant voltage request load (for example, an input voltage) that is an electric load that requires a stable voltage input to the power supply system having the two switches. Consider a configuration in which an electrical load is connected so that the operation is reset when the voltage drops. In this configuration, there is a concern that the output voltage of the first storage battery and the second storage battery decreases as the charging rate decreases, and the input voltage to the constant voltage required load decreases. Therefore, as in the case of Patent Document 1, it can be considered that a voltage is supplied stably to a constant voltage required load by connecting the booster circuit in parallel to the switch. In this case, if the configuration is such that the electric power generated by the rotating electrical machine is input from the rotating electrical machine to the booster circuit, it is necessary to improve the voltage resistance of the booster circuit. Cause problems.

  The present invention has been made in view of the above problems, and it is possible to suppress a power supply failure in a constant voltage required load while suppressing large power from the rotating electrical machine to the booster circuit. The main purpose is to provide a simple power supply system.

  A 1st structure is a power supply provided with the rotary electric machine (17) which has a function as a generator, and the 1st storage battery (11) and the 2nd storage battery (12) respectively connected in parallel with respect to the said rotary electric machine. A system, a path connecting a first connection point (N1) to which the first storage battery is connected and a second connection point (N2) to which the second storage battery is connected, the first connection point and the rotation Only two routes out of the three routes of the route connecting the third connection point (N3) to which the electric machine is connected and the route connecting the second connection point and the third connection point are respectively the first. A first switch (21) for switching between conduction and blocking of the first path, a second switch (22) for switching conduction and blocking of the second path, and a first switch for the first switch Or the first switch and the front Connected in parallel to the second switch comprises a booster circuit (24) for outputting boosts the voltage input from the first battery or the second battery.

  A booster circuit that boosts and outputs a voltage input from the first storage battery or the second storage battery is provided, and the booster circuit and the first switch or the first switch and the second switch are connected in parallel. In the configuration in which the first switch and the booster circuit are connected in parallel, for example, control is performed to turn on the first switch in a situation where power generation is performed in the rotating electrical machine. In the configuration in which the first switch, the second switch, and the booster circuit are connected in parallel, for example, in a situation where power generation is performed in the rotating electrical machine, both the first switch and the second switch are turned on. Implement control. If this control is performed, the current that flows from the rotating electrical machine to each storage battery flows through the first switch, or the first switch and the second switch. Input of power can be suppressed.

  Furthermore, if the constant voltage request | requirement load which requests | requires that a fixed voltage is input as an input voltage is connected with respect to the connection point where the output side of a booster circuit is connected, the output voltage of a 1st storage battery and a 2nd storage battery will be Even when the voltage drops, the boosted power can be supplied from the booster circuit to the constant voltage request load. For this reason, it is possible to suppress power supply failure in the constant voltage required load.

  According to a second configuration, in the first configuration, the power supply system includes a switch control device (30) that performs open / close control of the first switch and the second switch, and the switch control device includes the rotating electrical machine. When power generation is performed in the above, the first switch and the second switch that are connected in parallel with the booster circuit are turned on.

  In a configuration in which the first switch and the booster circuit are connected in parallel under a situation where power generation is performed in the rotating electrical machine, the first switch is turned on, and the first switch, the second switch, and the booster circuit are connected in parallel. In the connected configuration, control is performed to turn on both the first switch and the second switch. If this control is carried out, the current flowing from the rotating electrical machine to each storage battery flows through the first switch or the second switch, so that large power is input from the rotating electrical machine to the booster circuit. This can be suppressed.

  According to a third configuration, in the first or second configuration, an input voltage is in a predetermined voltage range with respect to a connection point connected to an output side of the booster circuit among the first to third connection points. A constant voltage required load (14) that is required to be connected is connected.

  If the constant voltage required load which requires that a constant voltage is input as an input voltage is connected to the connection point to which the output side of the booster circuit is connected, the output voltages of the first storage battery and the second storage battery are reduced. Even in this case, the boosted power can be supplied from the booster circuit to the constant voltage request load. For this reason, it is possible to suppress power supply failure in the constant voltage required load.

  According to a fourth configuration, in any one of the first to third configurations, a path connecting the first connection point and the third connection point is provided as the first path, and the second connection point and the A path connecting a third connection point is provided as the second path, and the booster circuit is connected in parallel to the first switch.

  A path connecting the first storage battery and the rotating electrical machine is a first path, and a path connecting the second storage battery and the rotating electrical machine is a second path. With this configuration, one of the first storage battery and the second storage battery can be selectively connected to the rotating electrical machine.

  Further, the booster circuit is connected in parallel to the first switch. When the booster circuit is configured to boost the input voltage input from the third connection point (the rotating electrical machine and the second storage battery), a constant voltage required load is connected to the first connection point (first storage battery). Thus, it is possible to supply the electric power boosted by the booster circuit to the constant voltage required load. For this reason, the power supply failure in a constant voltage load can be suppressed.

  Similarly, when the booster circuit boosts the input voltage input from the first connection point (first storage battery) side, a constant voltage required load is connected to the third connection point (rotating electrical machine and second storage battery). By doing so, it becomes possible to supply the power boosted by the booster circuit to the constant voltage required load. For this reason, the power supply failure in a constant voltage load can be suppressed.

  According to a fifth configuration, in the fourth configuration, the rotating electrical machine has a function as an electric motor, and the booster circuit boosts an input voltage input from the third connection point side, and Output to the first connection point side.

  In this configuration, the booster circuit boosts the input voltage input from the third connection point (the rotating electrical machine and the second storage battery) and outputs it to the first connection point (first storage battery). In this configuration, for example, the power boosted by the booster circuit is supplied to the constant voltage request load by connecting the constant voltage request load to the first connection point (first storage battery) as in the third configuration. It becomes possible. For this reason, the power supply failure in a constant voltage load can be suppressed.

  Further, in this configuration in which the rotating electrical machine functions as an electric motor, the rotating electrical machine and a constant voltage required load are connected via a first switch. As a result, even when the rotating electrical machine operates as an electric motor and the voltage on the third connection point side decreases, the voltage supplied to the constant voltage request load can be reduced by turning the first switch off. The decrease can be suppressed.

  According to a sixth configuration, in the fifth configuration, the power supply system includes a switch control device (30) that performs opening / closing control of the first switch and the second switch, and the switch control device includes the rotating electrical machine. When operating as an electric motor, the first switch is turned off and the second switch is turned on.

  In the fifth configuration, when the rotating electrical machine operates as a motor (powering operation), a large current flows from the storage battery to the rotating electrical machine. For this reason, due to a voltage drop or the like in the internal resistance of the storage battery, the output voltage of the storage battery that supplies power to the rotating electrical machine decreases. As the output voltage of the storage battery decreases, for example, when a constant voltage request load is connected to the third connection point, there is a concern that the operation of the constant voltage request load becomes unstable.

  Therefore, when the rotating electrical machine operates as an electric motor, a switch control device is provided in which the first switch is turned off and the second switch is turned on. By turning on the second switch, it is possible to supply power from the second storage battery to the rotating electrical machine. Further, by turning off the first switch, it is possible to suppress a decrease in voltage at the third connection point due to the operation (powering operation) of the rotating electrical machine as an electric motor and to connect to the third connection point. It becomes possible to supply electric power from both the first storage battery and the booster circuit to the electric load.

  According to a seventh configuration, in the fifth or sixth configuration, the second storage battery has higher power efficiency in charging and discharging than the first storage battery.

  In the fifth and sixth configurations, the second storage battery supplies power to the rotating electrical machine that operates as an electric motor and the electric load that is connected to the third connection point via the booster circuit. That is, the amount of power supplied by the second storage battery is greater than the amount of power supplied by the first storage battery. Therefore, by setting the second storage battery to have higher power efficiency in charging and discharging than the first storage battery, it is possible to improve the power efficiency of the entire power supply system while making the power supply system inexpensive. For example, the first storage battery may be a lead storage battery and the second storage battery may be a lithium ion storage battery.

  The eighth configuration is applied to any one of the power supply systems of the first to seventh configurations, and the second storage battery, the first path and the second path, the first switch and the second switch, A battery unit (U) having the booster circuit therein.

  According to this configuration, for example, the attachment of the power supply system to a vehicle or the like can be simplified. Further, for example, if the first power supply is provided outside the battery unit, the battery unit need not be disassembled when the first power supply is abnormal or deteriorated, and the process of replacing the first power supply is simplified. Can be

The figure showing the electric constitution of a 1st embodiment. The figure showing the state of the power supply system at the time of power-off. The figure showing the state of the power supply system immediately after starting of a vehicle system. The figure showing the state of the power supply system at the time of regenerative power generation. The figure showing the state of a power supply system during driving | running | working of a vehicle except the time of regenerative power generation. The flowchart showing the control processing of the power supply system of 1st Embodiment. The flowchart showing the control processing of the power supply system of 2nd Embodiment. The figure showing the electric constitution in a 3rd embodiment. The figure showing the electric constitution in a 4th embodiment. The figure showing the electric constitution in a 5th embodiment. The figure showing the electric constitution in a 6th embodiment. The figure showing the electric constitution in a 7th embodiment. The figure showing the electric constitution in 8th Embodiment. The figure showing the electric constitution in a 9th embodiment. The figure showing the electric constitution in a 10th embodiment. The figure showing the electric constitution in an 11th embodiment.

(First embodiment)
DESCRIPTION OF EXEMPLARY EMBODIMENTS Embodiments of the invention will be described below with reference to the drawings. In the present embodiment, an in-vehicle power supply system that supplies power to various devices of the vehicle in a vehicle that runs using an engine (internal combustion engine) as a drive source is embodied. The vehicle has a so-called idling stop function.

  As shown in FIG. 1, this power supply system is a dual power supply system having a lead storage battery 11 as a first storage battery and a lithium ion storage battery 12 as a second storage battery. Each storage battery 11, 12 can supply power to the starter 13 and various electric loads 14, 15. Further, the storage batteries 11 and 12 can be charged by the generator 16. In this system, the lead storage battery 11 and the lithium ion storage battery 12 are connected in parallel to the generator 16, and the lead storage battery 11 and the lithium ion storage battery 12 are connected in parallel to the electrical loads 14 and 15.

  The lead storage battery 11 is a well-known general-purpose storage battery. On the other hand, the lithium ion storage battery 12 is a high-density storage battery that has less power loss during charging / discharging than the lead storage battery 11, and has a high output density and energy density. The lithium ion storage battery 12 may be a storage battery having higher energy efficiency during charging / discharging than the lead storage battery 11. The lithium ion storage battery 12 is configured as an assembled battery having a plurality of battery cells connected in series or in parallel with each other. These storage batteries 11 and 12 have the same rated voltage, for example, 12V.

  The lithium ion storage battery 12 is housed in a housing case and configured as a battery unit U integrated with a substrate. In the present embodiment, the battery unit U constitutes a “power supply circuit device”. The battery unit U has connection terminals P1, P2, and P3 for connection to an external device. Among these, the lead storage battery 11, the starter 13, and the electric load 14 are connected to the connection terminals P1 and P2, and an output terminal. An electrical load 15 and a rotating electrical machine 17 are connected to P3.

  The electric loads 14 and 15 have different requirements for the voltage of the supplied power supplied from the storage batteries 11 and 12. Among these, the electric load 14 includes a constant voltage required load in which the supply voltage is required to be constant or at least within a predetermined voltage range. On the other hand, the electric load 15 is a general electric load other than the constant voltage required load. It can be said that the electric load 14 is a protected load. In addition, it can be said that the electric load 15 is a load that does not allow a power supply failure, and the electric load 14 is a load that allows a power supply failure compared to the electric load 15.

  Specific examples of the electric load 14 that is a constant voltage required load include various ECUs such as a navigation device, an audio device, a meter device, and an engine ECU. In this case, by suppressing the voltage fluctuation of the supplied power, it is possible to suppress an unnecessary reset or the like in each of the above devices, and to realize a stable operation. The electric load 14 may include a travel system actuator such as an electric steering device or a brake device. Specific examples of the electric load 15 include a seat heater, a heater for a defroster for a rear window, a headlight, a wiper for a front window, and a blower fan for an air conditioner.

  The rotating electrical machine 17 is connected to the output shaft of the engine 18 by a belt or the like. When the rotating electrical machine 17 operates as a generator, power is generated by the rotation of the engine output shaft, and the generated power is supplied to the storage batteries 11 and 12 and the electric loads 14 and 15. Further, when the rotating electrical machine 17 operates as an electric motor, electric power is supplied mainly from the lithium ion storage battery 12 among the storage batteries 11 and 12, and rotational force is applied to the engine output shaft.

  Here, a connection point between the lead storage battery 11 and the electric path constituting the power supply system is a first connection point N1, and a connection point between the lithium ion storage battery 12 and the electric path constituting the power supply system is a second connection point N2. A connection point between the rotating electrical machine 17 and the electric path constituting the power supply system is defined as a third connection point N3.

  Inside the battery unit U, a first path L1 connecting the connection terminals P1, P2 and a second path L2 connecting the connection point N3 on the first path L1 and the lithium ion storage battery 12 are provided as electrical paths. It has been. A first switch 21 is provided on the first path L1, and a second switch 22 is provided on the second path L2. More specifically, in the first path L1, a switch 21 is provided between the first connection terminal P1 to which the lead storage battery 11 is connected and the connection point N3, and in the second path L2, the lithium ion storage battery is more than the connection point N3. A switch 22 is provided on the 12 side. The electric power generated by the rotating electrical machine 17 is supplied to the lead storage battery 11 and the electric load 14 via the first path L1, and is supplied to the lithium ion storage battery 12 via the second path L2.

  Each of these switches 21 and 22 includes, for example, 2 × n MOSFETs (semiconductor switching elements) and is connected in series so that the parasitic diodes of the two sets of MOSFETs are opposite to each other. By this parasitic diode, when each switch 21 and 22 is turned off, the current flowing through the path in which the switch is provided is completely cut off. Note that IGBTs, bipolar transistors, or the like can be used as the switches 21 and 22 instead of MOSFETs. In the case where IGBTs or bipolar transistors are used as the switches 21 and 22, reverse diodes may be connected in parallel to the switches 21 and 22, respectively, instead of the parasitic diode.

  In addition, a bypass path Lb that bypasses the switch 21 is provided inside the battery unit U. The bypass path Lb is provided so as to connect the connection terminal P1 and the connection point N3 on the first path L1. By the bypass path Lb, the lead storage battery 11 and the electrical load 15 can be connected without using the switch 21.

  The bypass path Lb is provided with a bypass switch 23 that switches the bypass path Lb into a state of energization or de-energization. The bypass switch 23 is a normally closed and mechanical relay switch. If the bypass switch 23 is turned on, the generated power of the generator 16 can be supplied to the electric load 15 via the bypass path Lb even when the switch 21 is turned off. . The bypass path Lb is a dark current path that supplies dark current from the lead storage battery 11 to the electric load 15 in a stopped state of the power supply system, and power from the lead storage battery 11 to the electric load 15 when the fail safe process is performed. It also serves as a fail feeding path to be supplied.

  Here, in the configuration of the present embodiment, a path La that bypasses the switch 21 is provided inside the battery unit U. The path L1 is provided so as to connect the connection terminal P1 and the third connection point N3 on the first path L1. A booster circuit 24 is provided inside the battery unit U and on the path La. The booster circuit 24 boosts the power supplied from the connection terminal P2 side (third connection point N3 side) to a predetermined voltage and outputs it to the connection terminal P1 side (first connection point N1 side). The booster circuit 24 is, for example, a boost chopper circuit. Further, an insulation type DCDC converter may be used.

  The battery unit U includes a control unit 30 (switch control device), and each of the switches 21 to 23, the booster circuit 24, and the control unit 30 are accommodated in a housing in a state of being mounted on the same substrate, for example. ing. The switches 21 to 23, the booster circuit 24, and the control unit 30 may be separately mounted on a plurality of substrates. Further, the switches 21 to 23 may be not mounted on the substrate, for example, may be mounted directly on the storage case (housing) of the battery unit U.

  An ECU 40 outside the battery unit U is connected to the control unit 30. That is, the control unit 30 and various control devices including the ECU 40 are connected to each other via a communication network such as CAN and can communicate with each other, and are stored in the control unit 30 and various control devices including the ECU 40. Various data can be shared with each other. The ECU 40 is an electronic control device (traveling control device) having a function of performing idling stop control. As is well known, the idling stop control automatically stops the engine 18 when a predetermined automatic stop condition is satisfied, and restarts the engine 18 when the predetermined restart condition is satisfied under the automatic stop state. The ECU 40 controls the rotating electrical machine 17 and is included in the “power supply system”.

  The control unit 30 performs on / off (open / close) switching control of the switches 21 to 23, that is, open / close control, according to the operating state of the rotating electrical machine 17. In this case, the control unit 30 controls on / off of the switches 21 to 23 based on the running state of the vehicle and the storage state of the storage batteries 11 and 12. Thereby, charging / discharging is implemented using the lead storage battery 11 and the lithium ion storage battery 12 selectively.

  The charge / discharge control based on the storage state of each of the storage batteries 11 and 12 performed by the control unit 30 will be briefly described. The control unit 30 sequentially acquires the detected values of the terminal voltage or the open-circuit voltage of the lead storage battery 11 and the lithium ion storage battery 12, and sequentially supplies the energization current of the lead storage battery 11 and the lithium ion storage battery 12 detected by current detection means (not shown). get. Moreover, the control part 30 acquires sequentially the temperature of the lead storage battery 11 and the lithium ion storage battery 12 detected by the temperature detection part which is not shown in figure. The control unit 30 calculates the SOC (remaining capacity) of the lead storage battery 11 and the lithium ion storage battery 12 based on these acquired values, and supplies the SOC to the lithium ion storage battery 12 so that the SOC is maintained within a predetermined use range. The amount of charge and the amount of discharge are controlled.

  The control unit 30 of the present embodiment further drives the booster circuit 24 in accordance with the state of the rotating electrical machine 17 to boost the power supplied from the third connection point N3 side to a predetermined voltage to the first connection point N1. Output to the side (connection terminal P1 side).

  Hereinafter, the on / off control of the switches 21 to 23 and the drive of the booster circuit 24 by the control unit 30 will be described with reference to FIGS.

  As shown in FIG. 2, when the vehicle is stopped, that is, when the power of the vehicle system is off (IG off), the control unit 30 turns off the switches 21 and 22 and turns on the bypass switch 23. Further, the driving of the booster circuit 24 is stopped. Thereby, electric power is supplied from the lead storage battery 11 to the electric load 15 via the bypass path Lb. The switches 21 and 22 are semiconductor switching elements, and are normally open switching elements that are turned off when the input of the drive signal is stopped. The bypass switch 23 is a mechanical relay switch, This is a normally-closed opening / closing element that is turned on when input of a drive signal is stopped.

  As shown in FIG. 3, when the calculation of the SOC of the lithium ion storage battery 12 is not completed immediately after the start of the vehicle system, or when the temperature is low, the control unit 30 turns off the switch 22 to turn off the lithium ion storage battery. 12 charging / discharging is stopped. In addition, the control unit 30 stops charging / discharging of the lithium ion storage battery 12 by turning off the switch 22 even when the engine is started using the starter 13 immediately after the vehicle system is started. Moreover, the control part 30 implements the electric power supply from the lead storage battery 11 to the electric load 15 by turning on the switch 21.

  Further, the control unit 30 is configured such that the lithium ion storage battery 12 is in a low SOC (overdischarge state) during the power running operation of the rotating electrical machine 17 or the lithium ion storage battery 12 is in a high SOC (overcharged) during the regenerative power generation of the rotating electrical machine 17. In the same way, the charging / discharging of the lithium ion storage battery 12 is stopped by turning off the switch 22.

  When the vehicle is decelerated, regenerative power generation by the rotating electrical machine 17 is performed. In this case, as shown in FIG. 4, the control unit 30 turns on both the switches 21 and 22, and supplies power from the regenerative power generation of the rotating electrical machine 17 to the lead storage battery 11 and the lithium ion storage battery 12. Thereby, each storage battery 11 and 12 is charged appropriately.

  As shown in FIG. 5, in the engine running state, the assist running state, and the EV running state, the control unit 30 turns off the first switch 21 and turns on the second switch 22. In this state, since the first connection terminal P1 and the second connection terminal P2 are cut off, the electric load 14 is supplied with electric power from the lead storage battery 11, and the electric load 15 is supplied with electric power from the lithium ion storage battery 12. Supply is made.

  Here, the engine running state is a state in which fuel injection (fuel consumption) is performed in the engine 18 and both the regenerative operation and the power running operation in the rotating electrical machine 17 are stopped. The assist travel state is a state in which fuel injection is performed in the engine 18 and a power running operation is performed in the rotating electrical machine 17. The engine 18 and the rotating electrical machine 17 share the driving force. It is. The EV traveling state is a state in which the rotating electrical machine 17 applies a rotational force to the output shaft of the engine 18 after the engine 18 is brought into a non-combustion state. Switching between the engine travel state, the assist travel state, and the EV travel state is performed by the ECU 40.

  If the engine restart condition is satisfied during the engine automatic stop in the idling stop control, the ECU 40 starts the engine by the rotating electrical machine 17. An engine restart condition is established by performing a brake pedal depressing operation or an accelerator pedal depressing operation in the vehicle. When the engine is restarted in the idling stop control, the control unit 30 turns off the first switch 21 and turns on the second switch 22 as shown in FIG. Electric power is supplied and the rotating electrical machine 17 starts the engine. At this time, since electric power is supplied from the lithium ion storage battery 12 to the rotating electrical machine 17 and electric power is supplied from the lead storage battery 11 to the electric load 14, voltage fluctuation occurs in the electric power supplied to the electric load 14. It has never been.

  Further, the control unit 30 of the present embodiment turns off the first switch 21 and the second switch 22 and outputs a predetermined voltage from the booster circuit 24 during traveling of the vehicle except during regenerative power generation. . Here, “when the vehicle is running except during regenerative power generation” means when the engine is running, during assist running, and when the engine is restarted in idling stop control.

  According to this configuration, power supply to the electric load 14 is performed from both the lead storage battery 11 and the booster circuit 24. That is, the lithium ion storage battery 12 performs part of the power supply to the electric load 14 via the booster circuit 24. Since the lithium ion storage battery 12 has a higher power efficiency in charging / discharging than the lead storage battery 11, increasing the power shared by the lithium ion storage battery 12 can improve the power efficiency of the entire power supply system. Moreover, since the 1st switch 21 is made into the OFF state as mentioned above, even if it is a case where the output voltage of the lithium ion storage battery 12 falls temporarily with operation | movement of the rotary electric machine 17, the input voltage with respect to the electrical load 14 Can be suppressed.

  Further, when power is supplied from the booster circuit 24 to the lead storage battery 11 and the lead storage battery 11 is charged, the lead storage battery 11 is charged using the power stored in the lithium ion storage battery 12. In this case, the power efficiency of the entire power supply system is deteriorated due to the power loss in the internal resistance in both storage batteries 11 and 12 and the power loss in the booster circuit 24.

  Therefore, the control unit 30 adjusts the output voltage (predetermined voltage) of the booster circuit 24 so as to be equal to or lower than the open end voltage of the lead storage battery 11. Thereby, it is suppressed that the lead storage battery 11 is charged with the electric power supplied from the lithium ion storage battery 12 to the 1st connection terminal P1 side via the booster circuit 24, and the deterioration of the power efficiency of the whole power supply system is suppressed. Further, the control unit 30 adjusts the output voltage of the booster circuit 24 to be substantially the same as the open-end voltage of the lead storage battery 11. Thereby, the electric power output in the lead storage battery 11 can be suppressed, and the electric power supply with respect to the electric load 14 can be mainly allocated to the booster circuit 24, that is, the lithium ion storage battery 12.

  In addition, the control unit 30 controls the control unit 30 when the charging rate of the lithium ion storage battery 12 is lower than a predetermined value or when an abnormality occurs in the lithium ion storage battery 12 even during traveling of the vehicle except during regenerative power generation. However, the switch 21 is turned on and the switch 22 is turned off. Here, the predetermined value used for determination of the charging rate of the lithium ion storage battery 12 is set to a value that can suppress the lithium ion storage battery 12 from being overdischarged. With this control, when the charging rate of the lithium ion storage battery 12 is low, the discharge in the lithium ion storage battery 12 is stopped, and power supply from the lead storage battery 11 to the electric loads 14 and 15 and the rotating electrical machine 17 is performed. Is done.

  Control processing of the power supply system of the present embodiment will be described using the flowchart shown in FIG. The control process is performed every predetermined period.

  In step S01, it is determined whether or not the power supply system is on. When the power supply system is in an off state (S01: NO), in steps S02, the switches 21 and 22 are turned off, the switch 23 is turned on, the operation of the booster circuit 24 is stopped, and the process is terminated. If the power supply system is in the on state (S01: YES), in step S03, it is determined whether or not the power supply system has just been activated. If it is immediately after the power supply system is activated (S03: YES), in step S04, the switch 21 is turned on, the switches 22, 23 are turned off, the operation of the booster circuit 24 is stopped, and the process is terminated. In addition, when predetermined time passes since starting of a power supply system and the start of the engine 18 by the starter 13 is not implemented, it determines with it not being immediately after starting of a power supply system.

  If it is not immediately after starting the power supply system (S03: YES), it is determined in step S05 whether or not the lithium ion storage battery 12 is in a usable state. When the lithium ion storage battery 12 cannot be used (S05: NO), the process of step S04 is performed. When the lithium ion storage battery 12 is in a usable state (S05: YES), in step S06, it is determined whether or not regenerative power generation is being performed.

  If regenerative power generation is being performed (S06: YES), in steps S07, the switches 21 and 22 are turned on, the switch 23 is turned off, the booster circuit 24 is stopped, and the process is terminated. When regenerative power generation is not being performed (S06: NO), in step S08, the switch 22 is turned on, the switches 21 and 23 are turned off, the booster circuit 24 is operated, and the process is terminated.

(Second Embodiment)
In the first embodiment, during traveling of the vehicle except during regenerative power generation, the control unit 30 turns off the first switch 21 and turns on the second switch 22, and outputs a predetermined voltage from the booster circuit 24. The configuration. In the second embodiment, the configuration is changed as follows. During traveling of the vehicle except during regenerative power generation, the controller 30 does not change the configuration in which the first switch 21 is turned off and the second switch 22 is turned on, while the vehicle is traveling except during regenerative power generation, and When the output voltage of the lead storage battery 11 is less than a predetermined value, the control unit 30 operates the booster circuit 24. In addition, the control unit 30 is configured to stop the operation of the booster circuit 24 while the vehicle is running except during regenerative power generation and when the output voltage of the lead storage battery 11 is equal to or higher than a predetermined value. In addition, the control unit 30 sets the first switch 21 to the on state and the second switch 22 to the off state when the lithium ion storage battery 12 is in an overdischarged or low temperature state and the lithium ion storage battery 12 cannot be used. The discharge in the lithium ion storage battery 12 is stopped.

  According to this configuration, when the output voltage of the lead storage battery 11 is equal to or higher than a predetermined value, power is supplied from only the lead storage battery 11 to the electric load 14, and when the output voltage of the lead storage battery 11 is less than the predetermined value, lead is supplied. Electric power is supplied to the electrical load 14 from the storage battery 11 and the booster circuit 24 (or only the booster circuit 24). Here, if the predetermined value used for determination of the output voltage of the lead storage battery 11 is set to be equal to or higher than the minimum value of the voltage at which the electric load 14 can operate, the electric load 14 can be stably operated.

  The stable operation of the electric load 14 can also be realized by the control of the present embodiment. Further, by reducing the period during which the lead storage battery 11 is charged from the lithium ion storage battery 12 through the booster circuit 24, the discharge from the lithium ion storage battery 12 to the lead storage battery 11 is suppressed, and the power as the entire power supply system Efficiency can be reduced. In addition, by reducing the period during which the booster circuit 24 operates, it is possible to reduce power loss due to the operation of the booster circuit 24 and improve the power efficiency of the entire power supply system.

  Control processing of the power supply system of the present embodiment will be described using the flowchart shown in FIG. The control process is performed every predetermined period. The description of the same configuration as in FIG. 6 is omitted.

  When regenerative power generation is not being performed (S06: NO), in step S09, it is determined whether or not the output voltage (V (Pb)) of the lead storage battery 11 is less than a predetermined value. When the output voltage of the lead storage battery 11 is less than the predetermined value (S09: YES), the process of step S08 is performed and the process is terminated. When the output voltage of the lead storage battery 11 is equal to or higher than the predetermined value (S09: NO), in step S10, the switch 22 is turned on, the switches 21, 23 are turned off, the booster circuit 24 is stopped, and the process is terminated.

(Third embodiment)
In the first and second embodiments, the first switch 21 and the first switch 21 are connected in parallel between the first connection point N1 to which the lead storage battery 11 is connected and the third connection point N3 to which the rotating electrical machine 17 is connected. The booster circuit 24 to be connected is provided, and the second switch 22 is provided between the second connection point N2 and the third connection point N3 to which the lithium ion storage battery 12 is connected. You may change the said structure to the structure shown to the following FIGS. 8-16 (3rd-12th embodiment). 8 to 16, configurations other than the storage batteries 11 and 12, the constant voltage request load 14, the rotating electrical machine 17, the switches 21 and 22, and the booster circuit 24 are omitted. 8-16, the direction of the electric power output of the booster circuit 24 is shown using an arrow.

  In the configuration shown in FIG. 8, the first connection point N1 and the second connection point N2 are connected by an electrical path, and the second connection point N2 and the third connection point N3 are connected by an electrical path. A first switch 21 and a booster circuit 24 connected in parallel to the first switch 21 are provided between the first connection point N1 and the second connection point N2, and the second connection point N2 and the third connection point N3 are connected. A second switch 22 is provided between them. The booster circuit 24 boosts the power supplied from the second connection point N2 side to a predetermined voltage and outputs it to the first connection point N1 side.

  In this configuration, the constant voltage request load 14 is connected to the first connection point N1. During the power running operation of the rotating electrical machine 17, the control unit 30 turns off the first switch 21 to suppress a decrease in the input voltage to the constant voltage request load 14 associated with the operation of the rotating electrical machine 17. Further, during the power running operation of the rotating electrical machine 17, the control unit 30 can supply power from the lead storage battery 11 and the booster circuit 24 to the constant voltage request load 14 by operating the booster circuit 24.

(Fourth embodiment)
In the configuration shown in FIG. 9, the first connection point N1 and the second connection point N2 are connected by an electrical path, and the first connection point N1 and the third connection point N3 are connected by an electrical path. A first switch 21 and a booster circuit 24 connected in parallel to the first switch 21 are provided between the first connection point N1 and the second connection point N2, and the first connection point N1 and the third connection point N3 are connected. A second switch 22 is provided between them. The booster circuit 24 boosts the power supplied from the first connection point N1 side to a predetermined voltage and outputs it to the second connection point N2 side.

  In this configuration, the constant voltage request load 14 is connected to the second connection point N2. During the power running operation of the rotating electrical machine 17, the control unit 30 turns off the first switch 21 to suppress a decrease in the input voltage to the constant voltage request load 14 associated with the operation of the rotating electrical machine 17. Further, during the power running operation of the rotating electrical machine 17, the control unit 30 can supply power from the lithium ion storage battery 12 and the booster circuit 24 to the constant voltage required load 14 by operating the booster circuit 24.

(Fifth embodiment)
In the configuration shown in FIG. 10, the first connection point N1 and the third connection point N3 are connected by an electrical path, and the second connection point N2 and the third connection point N3 are connected by an electrical path. A first switch 21 and a booster circuit 24 connected in parallel to the first switch 21 are provided between the second connection point N2 and the third connection point N3, and the first connection point N1 and the third connection point N3 are connected. A second switch 22 is provided between them. The booster circuit 24 boosts the power supplied from the third connection point N3 side to a predetermined voltage and outputs it to the second connection point N2 side.

  In this configuration, the constant voltage request load 14 is connected to the second connection point N2. During the power running operation of the rotating electrical machine 17, the control unit 30 turns off the first switch 21 to suppress a decrease in the input voltage to the constant voltage request load 14 associated with the operation of the rotating electrical machine 17. Further, during the power running operation of the rotating electrical machine 17, the control unit 30 can supply power from the lithium ion storage battery 12 and the booster circuit 24 to the constant voltage required load 14 by operating the booster circuit 24.

(Sixth embodiment)
In the configuration shown in FIG. 11, the first connection point N1 and the second connection point N2 are connected by an electrical path, the second connection point N2 and the third connection point N3 are connected by an electrical path, and the first connection point N1. And the third connection point N3 are connected by an electric path. A first switch 21 is provided between the first connection point N1 and the second connection point N2, and a second switch 22 is provided between the second connection point N2 and the third connection point N3. Further, a booster circuit 24 connected in parallel to the first switch 21 and the second switch 22 is provided between the first connection point N1 and the third connection point N3. Further, the booster circuit 24 boosts the power supplied from the third connection point N3 side to a predetermined voltage and outputs it to the first connection point N1 side.

  In this configuration, the constant voltage request load 14 is connected to the first connection point N1. When the control unit 30 turns off the first switch 21, a decrease in the input voltage to the constant voltage request load 14 due to the operation of the rotating electrical machine 17 is suppressed. Further, the control unit 30 outputs the predetermined voltage from the booster circuit 24 while turning on the second switch 22, so that power can be supplied from the lead storage battery 11 and the booster circuit 24 to the constant voltage request load 14. In addition, the control unit 30 performs power supply from the lithium ion storage battery 12 to the rotating electrical machine 17 by turning on the second switch 22 during the power running operation of the rotating electrical machine 17.

(Seventh embodiment)
In the configuration shown in FIG. 12, the first connection point N1 and the second connection point N2 are connected by an electrical path, the second connection point N2 and the third connection point N3 are connected by an electrical path, and the first connection point N1 is connected. And the third connection point N3 are connected by an electric path. A first switch 21 is provided between the first connection point N1 and the third connection point N3, and a second switch 22 is provided between the second connection point N2 and the third connection point N3. In addition, a booster circuit 24 connected in parallel to the first switch 21 and the second switch 22 is provided between the first connection point N1 and the second connection point N2. The booster circuit 24 boosts the power supplied from the second connection point N2 side to a predetermined voltage and outputs it to the first connection point N1 side.

  In this configuration, the constant voltage request load 14 is connected to the first connection point N1. When the control unit 30 turns off the first switch 21, a decrease in the input voltage to the constant voltage request load 14 due to the power running operation of the rotating electrical machine 17 is suppressed. Further, the control unit 30 outputs a predetermined voltage from the booster circuit 24, so that power can be supplied from the lead storage battery 11 and the booster circuit 24 to the constant voltage request load 14. In addition, the control unit 30 performs power supply from the lithium ion storage battery 12 to the rotating electrical machine 17 by turning on the second switch 22 during the power running operation of the rotating electrical machine 17.

(Eighth embodiment)
In the configuration shown in FIG. 13, the first connection point N1 and the second connection point N2 are connected by an electrical path, the second connection point N2 and the third connection point N3 are connected by an electrical path, and the first connection point N1 is connected. And the third connection point N3 are connected by an electric path. A first switch 21 is provided between the second connection point N2 and the third connection point N3, and a second switch 22 is provided between the first connection point N1 and the third connection point N3. Further, a booster circuit 24 connected in parallel to the first switch 21 and the second switch 22 is provided between the first connection point N1 and the third connection point N3. Further, the booster circuit 24 boosts the power supplied from the first connection point N1 side to a predetermined voltage and outputs it to the second connection point N2 side.

  In this configuration, the constant voltage request load 14 is connected to the second connection point N2. When the control unit 30 turns off the first switch 21, a decrease in the input voltage to the constant voltage request load 14 due to the power running operation of the rotating electrical machine 17 is suppressed. Furthermore, the control unit 30 can supply power from the lithium ion storage battery 12 and the booster circuit 24 to the constant voltage request load 14 by outputting a predetermined voltage from the booster circuit 24. Further, the control unit 30 performs power supply from the lead storage battery 11 to the rotating electrical machine 17 by turning on the second switch 22 during the power running operation of the rotating electrical machine 17.

(Ninth embodiment)
In the configuration shown in FIG. 14, the first connection point N1 and the second connection point N2 are connected by an electrical path, the second connection point N2 and the third connection point N3 are connected by an electrical path, and the first connection point N1 is connected. And the third connection point N3 are connected by an electric path. A first switch 21 is provided between the first connection point N1 and the second connection point N2, and a second switch 22 is provided between the first connection point N1 and the third connection point N3. In addition, a booster circuit 24 connected in parallel to the first switch 21 and the second switch 22 is provided between the second connection point N2 and the third connection point N3. Further, the booster circuit 24 boosts the power supplied from the third connection point N3 side to a predetermined voltage and outputs it to the second connection point N2 side.

  In this configuration, the constant voltage request load 14 is connected to the second connection point N2. When the control unit 30 turns off the first switch 21, a decrease in the input voltage to the constant voltage request load 14 due to the power running operation of the rotating electrical machine 17 is suppressed. Further, the control unit 30 can turn on the second switch 22 and output a predetermined voltage from the booster circuit 24, thereby supplying power from the lithium ion storage battery 12 and the booster circuit 24 to the constant voltage request load 14. Become.

(10th Embodiment)
In the configuration shown in FIG. 15, the first connection point N1 and the second connection point N2 are connected by an electrical path, and the first connection point N1 and the third connection point N3 are connected by an electrical path. A first switch 21 and a booster circuit 24 connected in parallel to the first switch 21 are provided between the first connection point N1 and the third connection point N3, and the first connection point N1 and the second connection point N2 are connected. A second switch 22 is provided between them. Further, the booster circuit 24 boosts the power supplied from the first connection point N1 side to a predetermined voltage and outputs it to the third connection point N3 side.

  In this configuration, the constant voltage request load 14 is connected to the third connection point N3. When the control unit 30 turns off the first switch 21 and outputs a predetermined voltage from the booster circuit 24, the booster circuit 24 supplies the constant voltage required load 14 and the rotating electrical machine 17 with stable voltage at the predetermined voltage. It becomes possible.

(Eleventh embodiment)
In the configuration shown in FIG. 16, the first connection point N1 and the second connection point N2 are connected by an electrical path, and the second connection point N2 and the third connection point N3 are connected by an electrical path. A first switch 21 and a booster circuit 24 connected in parallel to the first switch 21 are provided between the second connection point N2 and the third connection point N3, and the second connection point N2 and the third connection point N3 are connected. A second switch 22 is provided between them. The booster circuit 24 boosts the power supplied from the second connection point N2 side to a predetermined voltage and outputs it to the third connection point N3 side.

  In this configuration, the constant voltage request load 14 is connected to the third connection point N3. When the control unit 30 turns off the first switch 21 and outputs a predetermined voltage from the booster circuit 24, the booster circuit 24 supplies the constant voltage required load 14 and the rotating electrical machine 17 with stable voltage at the predetermined voltage. It becomes possible.

(Other embodiments)
-The structure which abbreviate | omits bypass path | route Lb and bypass switch 23 may be sufficient. A semiconductor switch may be employed as the bypass switch 23.

  As the first and second switches 21 and 22, an IGBT or the like may be used instead of the MOSFET. In addition, when IGBT is employ | adopted as the 1st, 2nd switches 21 and 22, a set of diodes in which the cathode electrodes or the anode electrodes are connected to each other corresponds to the corresponding first and second switches 21 and 22. It is good to set it as the structure connected in parallel to each.

  Furthermore, the first and second switches 21 and 22 are not limited to semiconductor switching elements. If the switching speed of the switch from on to off and from off to on can correspond to the switching of the running state of the vehicle such as switching from the stop to the EV running, the first and second switches As 21 and 22, for example, mechanical relay switches may be used.

  The booster circuit may be a bidirectional DCDC converter. That is, for example, in the configuration of the first embodiment, in addition to the function of boosting the power supplied from the connection point N1 side to a predetermined voltage and outputting it to the connection terminal P1 side, the power supplied from the connection terminal P1 side May be provided with a function of boosting the voltage to a predetermined voltage and outputting it to the connection point N1 side.

  In the first embodiment and the second embodiment, the control unit 30 performs control by regarding the bypass switch 23 as a “first switch” when an abnormality such as a normally open abnormality occurs in the first switch 21. May be.

  In the first and second embodiments, the booster circuit 24 boosts the power supplied from the third connection point (second connection terminal P2) side, and the first connection point N1 (first connection terminal P1) side Output to. The configuration is changed so that the booster circuit 24 boosts the power supplied from the first connection point (first connection terminal P1) side and outputs the boosted power to the third connection point (second connection terminal P2) side. Also good.

  In the said structure, it is good to set it as the structure which connects the electric load 14 which is a constant voltage request | requirement load to the 3rd connection point N3. When the control unit 30 turns off the first switch 21 and outputs a predetermined voltage from the booster circuit 24, the booster circuit 24 supplies the constant voltage required load 14 and the rotating electrical machine 17 with stable voltage at the predetermined voltage. It becomes possible.

  In the first embodiment, the control unit 30 is configured to adjust the output voltage of the booster circuit 24 to be substantially the same as the open-end voltage of the lead storage battery 11, but this may be changed. For example, the control unit 30 acquires a detected value of the input current input to the electric load 14 and performs current feedback control so that the output current of the booster circuit 24 becomes equal to the input current of the electric load 14. Also good. By performing the control, all the power consumption of the electric load 14 is supplied from the booster circuit 24, and the power stored in the lithium ion storage battery 12 out of the storage batteries 11 and 12 is used preferentially. Can do. Thereby, the power efficiency of the whole power supply system can be improved.

  In the above embodiment, a lead storage battery is used as the “first storage battery” and a lithium ion storage battery is used as the “second storage battery”, but this may be changed. That is, the same type of storage battery may be used for the first storage battery and the second storage battery. Moreover, you may use another secondary battery like a nickel hydride storage battery, an electric double layer capacitor, a lithium ion capacitor, etc. as a 1st storage battery or a 2nd storage battery.

  The control unit 30 in the above embodiment switches the states of the switches 21 to 23 and operates and stops the booster circuit 24 based on the state of the rotating electrical machine 17 and the SOC (remaining capacity) of each of the storage batteries 11 and 12. It was set as the structure to do. It is good also as a structure which changes this and implements the switching of the states of the switches 21-23 based on the instruction | command of ECU40, and the operation | movement and a stop of the pressure | voltage rise circuit 24 from the control part 30. FIG. Further, the control unit 30 may have a control function of the rotating electrical machine 17 that is a part of the function of the ECU 40. Further, the control unit 30 switches the states of the switches 21 to 23 and operates and stops the booster circuit 24 based on a command from a control device other than the ECU 40, for example, a control device having only the control function of the rotating electrical machine 17. The structure to implement may be sufficient.

  Further, the configuration for switching the states of the switches 21 to 23 based on the state of the rotating electrical machine 17 and the SOC (remaining capacity) of each of the storage batteries 11 and 12 may be omitted from the control unit 30. That is, a control device other than the control unit 30 such as the ECU 40 acquires the SOC (remaining capacity) of each of the storage batteries 11 and 12 and switches the states of the switches 21 to 23 with respect to the control unit 30 based on the acquired value. Or, it may be one that commands the operation and stop of the booster circuit 24.

  In the above embodiment, the battery unit U includes the paths L 1 and L 2, the switches 21 and 22, the lithium ion storage battery 12 as the “second storage battery”, and the control as the “switch control device” inside the housing case. The unit 30 is provided and integrated. This integrated configuration may be omitted. That is, the paths L1 and L2, the switches 21 and 22, the lithium ion storage battery 12, and the control unit 30 may not be integrated.

  -The rotary electric machine 17 may have only a function as a generator.

  DESCRIPTION OF SYMBOLS 11 ... Lead acid battery, 12 ... Lithium ion storage battery, 17 ... Rotary electric machine, 21 ... 1st switch, 22 ... 2nd switch, 24 ... Booster circuit, L1 ... 1st path | route, L2 ... 2nd path | route, N1 ... 1st connection Point, N2 ... second connection point, N3 ... third connection point.

Claims (8)

A rotating electrical machine (17) having a function as a generator;
A first storage battery (11) and a second storage battery (12) connected in parallel to the rotating electrical machine, respectively,
A path connecting the first connection point (N1) to which the first storage battery is connected and the second connection point (N2) to which the second storage battery is connected, and the first connection point and the rotating electrical machine are connected. Of the three paths of the path connecting the third connection point (N3) and the path connecting the second connection point and the third connection point, only two paths are respectively the first path (L1) and As a second route (L2),
A first switch (21) for switching conduction and blocking of the first path; a second switch (22) for switching conduction and blocking of the second path;
A booster circuit (24) that is connected in parallel to the first switch or to the first switch and the second switch and boosts and outputs a voltage input from the first storage battery or the second storage battery. )When,
Power supply system comprising. The power supply system includes a switch control device (30) for performing opening / closing control of the first switch and the second switch,
2. The switch control device according to claim 1, wherein the switch control device turns on one of the first switch and the second switch that is connected in parallel with the booster circuit when generating power in the rotating electrical machine. Power system.   Among the first to third connection points, a constant voltage request load (14) required to have an input voltage within a predetermined voltage range is connected to a connection point to which the output side of the booster circuit is connected. The power supply system according to claim 1 or 2. A path connecting the first connection point and the third connection point is provided as the first path, and a path connecting the second connection point and the third connection point is provided as the second path.
The power supply system according to claim 1, wherein the booster circuit is connected in parallel to the first switch. The rotating electrical machine has a function as an electric motor,
The power supply system according to claim 4, wherein the booster circuit boosts an input voltage input from the third connection point side and outputs the boosted voltage to the first connection point side. The power supply system includes a switch control device (30) for performing opening / closing control of the first switch and the second switch,
6. The power supply system according to claim 5, wherein the switch control device turns off the first switch and turns on the second switch when the rotating electrical machine operates as an electric motor.   The power system according to claim 5 or 6, wherein the second storage battery has higher power efficiency in charging and discharging than the first storage battery. Applied to the power supply system according to any one of claims 1 to 7,
A battery unit (U) including the second storage battery, the first path and the second path, the first switch and the second switch, and the booster circuit therein.

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