JP2009268343A - Power supply apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply apparatus which meets supply of a stable high-voltage, and high reliability and high efficiency by simple constitution at the same time. <P>SOLUTION: The apparatus includes a series circuit 16 for a battery 13 and an electric storage portion 15, a DC/DC converter 17 connected so as to charge and discharge the electric storage portion 15, a switch 29 which is connected to the series circuit 16 and the battery 13 and switches to one of them, a motor 37 connected to output of the switch 29 through a power converter 36, and a control circuit 39 connected to the DC/DC converter 17, the switch 29 and the power converter 36. The control circuit 39 connects the switch 29 to a battery 13 side while the motor 37 performs a regenerative operation, connects the switch 29 to a series circuit 16 side while the motor performs power running, and charges the electric storage portion 15 by the DC/DC converter 17 if the electric storage portion 15 is discharged by the power running. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power supply device for a fuel efficiency-improving vehicle that performs idling stop and braking force regeneration.

  In recent years, from the viewpoint of protecting the global environment, there has been a demand for reduction of carbon dioxide emissions particularly by improving vehicle fuel efficiency. For this purpose, a regenerative system that collects braking energy of the vehicle as electric energy and supplies it to a vehicle driving motor, an idling stop system that stops the engine when the vehicle stops, and the like have been developed. Of these, the former system is proposed in, for example, Patent Document 1 below. FIG. 7 is a block circuit diagram of such a power supply device.

  The power supply device 101 shown in FIG. 7 has the following configuration. A capacitor C1 is connected in series to the positive electrode of the battery Eb. One end of each of the switches SW1 and SW2 is connected to both ends of the capacitor C1. Further, a voltage sensor 103 for detecting the voltage is connected to both ends of the capacitor C1. The other ends of the switches SW1 and SW2 and the negative electrode of the battery Eb are connected to the power converter 105. A motor M <b> 1 is connected to the power converter 105. A control circuit 107 is connected to the switches SW1 and SW2, the voltage sensor 103, and the power converter 105.

  Next, the operation of the power supply apparatus 101 will be described. When the motor M1 is regeneratively operated by braking the vehicle, the control circuit 107 determines that it is in a regenerative state based on a signal from the power converter 105. Thereby, if the output of the voltage sensor 103 is below a predetermined value, the control circuit 107 turns off the switch SW1 and turns on the switch SW2, thereby charging the regenerative power to the series circuit of the battery Eb and the capacitor C1, If the output of the voltage sensor 103 is larger than a predetermined value, the switch SW1 is turned on and the switch SW2 is turned off, so that only the battery Eb is charged with regenerative power.

  When the braking of the vehicle is finished and the motor M1 is in a power running operation, the control circuit 107 determines that the power running state is in accordance with a signal from the power converter 105. Thus, the control circuit 107 determines whether or not the output of the voltage sensor 103 is equal to or lower than the lowest level voltage value. If the output is larger than the lowest level voltage value, the switch SW1 is turned off and the switch SW2 is turned on. Thus, the series circuit of the battery Eb and the capacitor C1 is connected to the power converter 105. As a result, both output voltages Vout are input to the power converter 105, and the motor M1 is driven. Thereafter, along with the power supply, the voltage of the capacitor C1 decreases, and when the output of the voltage sensor 103 falls below the lowest level voltage value, the switch SW1 is turned on and the switch SW2 is turned off. Thereby, the output voltage Vout by only the battery Eb is input to the power converter 105, and the motor M1 is continuously driven.

As described above, the regenerative electric power is controlled by controlling the switches SW1 and SW2 so that the capacitor C1 can be charged during the regenerative operation, and is charged if the capacitor C1 can be discharged during the power running operation. It can be recovered effectively.
JP 2002-330545 A

  According to the above power supply device, it is possible to effectively recover the regenerative power, so that the fuel consumption can be improved. However, there are the following problems.

  The control circuit 107 is configured to control the switches SW1 and SW2 in accordance with the charging state of the capacitor C1, and to switch between charging only the battery Eb or charging the series circuit of the battery Eb and the capacitor C1. Depending on which one is switched, it is necessary to vary the charging voltage during regeneration, that is, the voltage output from the power converter 105. Therefore, there is a problem that the configuration of the power converter 105 is complicated.

  Further, since the regenerative power is charged in the series circuit of the battery Eb and the capacitor C1, when the battery Eb is fully charged, it cannot be charged any more even if the capacitor C1 is not charged. Therefore, there has been a problem that the regenerative power cannot be sufficiently recovered and the efficiency is lowered.

  Further, when the charging voltage of the capacitor C1 reaches a predetermined voltage while charging the series circuit of the battery Eb and the capacitor C1, it is necessary to switch the switches SW1 and SW2 while the charging current is flowing. At this time, when relays are used as the switches SW1 and SW2, the switch SW2 is turned off particularly in a state where the charging current is flowing, so that there is a problem that reliability may be lowered.

  Furthermore, when this power supply apparatus is applied to an idling stop system, there are the following problems.

  In the idling stop system, the motor M1 corresponds to a starter and a generator (starter generator). Accordingly, during the regenerative operation of the motor M1, the switches SW1 and SW2 are controlled so that both the capacitor C1 and the battery Eb are charged if the capacitor C1 is insufficiently charged, and only the battery Eb is charged if it is sufficient. Thereafter, when idling stop is completed and the motor M1 is driven as a starter to restart the engine, if the capacitor C1 is sufficiently charged, both the capacitor C1 and the battery Eb can be used. If the capacitor C1 is insufficiently charged, the battery is used. The switches SW1 and SW2 are controlled so as to supply power to the motor M1 only from Eb.

  Thus, since the capacitor C1 is charged only during regenerative operation, the capacitor C1 can be sufficiently charged when regenerative power is sufficiently obtained, for example, during braking from high-speed driving, but as in traffic jams. When repeating low speed driving and stopping, there is a possibility that the capacitor C1 cannot be sufficiently charged with regenerative power. In this case, particularly in a vehicle having a large displacement engine, the motor M1 is driven only by the battery Eb, so that there is a problem that the voltage drop of the battery Eb becomes large and it takes time to restart.

  The present invention solves the above-mentioned conventional problems, and provides a power supply device that can supply a stable high voltage during powering operation of the motor M1 and can simultaneously satisfy high reliability and high efficiency with a simple configuration. The purpose is to do.

  In order to solve the conventional problem, a power supply device of the present invention is connected to a battery, a power storage unit connected in series to the battery, and charging and discharging the power storage unit using the battery as an input source. A DC / DC converter, a motor that performs power running operation and generates power by regenerative operation, and power that is connected to the motor and that supplies power during the power running operation of the motor and converts regenerative power during the regenerative operation A switch that switches the connection between the converter and the power converter to either one of a series circuit of the battery and the power storage unit or only the battery, and a control connected to the DC / DC converter, the switch, and the power converter A circuit, and when the motor is performing the regenerative operation, the switch is connected to the battery side, and the motor performs the power running. When performing rolling, connect the switch to the series circuit side, the discharge amount of the power storage unit, in which so as to charge by the DC / DC converter.

  According to the power supply device of the present invention, the switch is connected to the battery side during the regenerative operation of the motor, and charging to the power storage unit is performed by the DC / DC converter, so there is no need to vary the output voltage of the power converter. Therefore, the configuration of the power converter is simplified. In addition, by operating the DC / DC converter, only the power storage unit can be charged arbitrarily, so that regenerative power can be recovered and high efficiency can be obtained.

  Further, since the switch only needs to be switched when the regenerative operation and power running operation of the motor are changed, the number of times of switching is small, and switching can be performed in a state where no current flows, so that high reliability of the switch can be obtained.

  Furthermore, since electric power is supplied from the series circuit of the battery and the power storage unit during the power running operation of the motor, the battery voltage drop can be compensated by the power storage unit, and a stable high voltage can be supplied.

  Accordingly, it is possible to realize a power supply apparatus that can simultaneously supply high voltage with stability and high reliability and high efficiency simultaneously with a simple configuration.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block circuit diagram of a power supply device according to Embodiment 1 of the present invention. FIG. 2 is a flowchart showing the operation of the power supply device according to Embodiment 1 of the present invention. In FIG. 1, thick lines indicate power system wirings, and thin lines indicate signal system wirings. In the first embodiment, a case where the power supply device is applied to a hybrid vehicle capable of running a motor and regenerating electric power will be described.

  In FIG. 1, the power supply device 11 has the following configuration. First, the power storage unit 15 is connected in series to the positive electrode of the battery 13 mounted on the vehicle to form a series circuit 16. The power storage unit 15 includes a power storage element such as a secondary battery or a large capacity capacitor.

  An input terminal 19 of a DC / DC converter 17 is connected to a connection point between the battery 13 and the power storage unit 15. The output terminal 21 of the DC / DC converter 17 is connected to the other terminal of the power storage unit 15. The ground terminal 23 of the DC / DC converter 17 is connected to the common ground with the negative electrode of the battery 13. By connecting in this way, the DC / DC converter 17 can charge and discharge the power storage unit 15 using the battery 13 side as an input source.

  A load 25 is connected to the battery 13 in parallel. The load 25 is various electrical components mounted on the vehicle.

  A first terminal 31 of a switch 29 is connected to a connection point between the series circuit 16 and the output terminal 21. The second terminal 33 of the switch 29 is connected to the positive electrode of the battery 13. Accordingly, the switch 29 can be switched to either the series circuit 16 or the battery 13. In the first embodiment, a relay is used as the switch 29.

  The common terminal 35 that is the output of the switch 29 is connected to a motor 37 that can perform a power running operation and a regenerative operation via a power converter 36. The power converter 36 performs driving of a motor and conversion of regenerative power, and is generally composed of an inverter circuit. In addition, since the power storage unit 15 is charged by the DC / DC converter 17, the power converter 36 does not need to vary the output voltage. Therefore, a simple configuration can be obtained. Further, the motor 37 is configured to perform power running by receiving power supply and to generate power by regenerative operation during vehicle braking.

  The DC / DC converter 17, the switch 29, and the power converter 36 are connected to the control circuit 39 by signal system wiring. The control circuit 39 includes a microcomputer and peripheral circuits. The control circuit 39 reads a voltage / current characteristic value VI for the battery 13 and the power storage unit 15 from the DC / DC converter 17 and controls the operation of the DC / DC converter 17. A switching signal SW for performing switching control 29 and a motor control signal Mcont for controlling the power converter 36 are output. In addition, by controlling the power converter 36 with the motor control signal Mcont, it is possible to perform control such as driving and stopping of the motor 37. Further, the control circuit 39 is also connected to a vehicle-side control circuit (not shown), and various information is exchanged by the data signal data.

  Next, the operation of the power supply device 11 will be described using the flowchart of FIG.

  First, for the initial start of the vehicle engine, the motor 37 may be driven by the battery 13 or may be driven by the series circuit 16 if the power storage unit 15 has sufficient power. Moreover, you may carry out with the starter provided separately and the method is not limited.

  When the engine is started and the flowchart of FIG. 2 is executed, the control circuit 39 switches the switch 29 to the second terminal 33 to which the battery 13 is connected (step number S11). Thereafter, it is determined whether or not the electric power of the power storage unit 15 is sufficiently stored (S13). The sufficient amount of electric power is the amount of electric power required for powering the motor 37. When a capacitor is used as the power storage unit 15, the determination can be easily made by this terminal voltage. In the case of using a secondary battery, it is necessary to obtain it by measuring the input / output amount of power of the secondary battery.

  If the power of the power storage unit 15 is not sufficient (No in S13), the control circuit 39 transmits a control signal cont to charge the power storage unit 15 to the DC / DC converter 17 (S15). In response to this, the DC / DC converter 17 charges the power storage unit 15. Then, it returns to S13 and continues charging until the electrical storage part 15 becomes sufficient electric energy.

  If the power of the power storage unit 15 is sufficient (Yes in S13), the initial charge to the power storage unit 15 is completed, and the standby state is set (S16). At this time, the DC / DC converter 17 can be stopped. By stopping it, unnecessary power consumption can be reduced.

  Next, the control circuit 39 determines whether or not the motor 37 is performing a power running operation (S17). The operating state of the motor 37 can be obtained from the data signal data from the vehicle side control circuit. Further, the regenerative operation and the power running operation of the motor 37 are switched by transmitting the motor control signal Mcont from the control circuit 39 to the power converter 36 by the data signal data from the vehicle side control circuit. This control is omitted in the flowchart of FIG.

  When performing the power running operation (Yes in S17), the control circuit 39 switches the switch 29 to the series circuit 16 side, that is, the first terminal 31 side (S18). Thereby, the electric power of the series circuit 16 of the battery 13 and the power storage unit 15 is supplied to the motor 37 via the power converter 36, and the power running operation of the motor 37 is executed.

  Next, when the power running operation continues, discharging of the battery 13 and the power storage unit 15 proceeds. Therefore, the control circuit 39 determines whether or not the power of the power storage unit 15 is sufficient (S19). This determination is the same operation as S13. If the electric power of the power storage unit 15 is sufficient (Yes in S19), the process returns to S17 to continue the power running operation. On the other hand, if the power storage unit 15 is discharged by the power running operation of the motor 37 and the stored power is not sufficient (No in S19), the power running operation is stopped (S20). Thereafter, the process returns to S17, but since the power running is stopped in S20, the power running is not performed in S17 (No in S17). This state includes a case where the motor 37 is performing a regenerative operation.

  During the period in which the power running operation is stopped (including the regenerative operation period), the switch 29 is switched to the battery 13 side, that is, the second terminal 33 side (S25). During the powering operation stop period, the power of the power storage unit 15 is determined. If the power of the power storage unit 15 is not sufficient (No in S26), the control circuit 39 charges the power storage unit 15 with respect to the DC / DC converter 17. A control signal cont is transmitted (S27). In response, DC / DC converter 17 charges power storage unit 15. In addition, it is effective to perform this charge during the period when the motor 37 is performing the regenerative operation. This is because the regenerative power can usually only be charged to the battery 13 and supplied to the load 25, but can also be used to charge the power storage unit 15 in the first embodiment. Thereafter, the process returns to S26.

  On the other hand, if the power of the power storage unit 15 is sufficient (Yes in S26), the process returns to S17 and the subsequent operations are repeated.

  In this way, by switching the switch 29 to the battery 13 side during the regenerative operation, regenerative power is supplied to the load 25, and the battery 13 is charged and the power amount of the power storage unit 15 becomes sufficient by the DC / DC converter 17. Since the power storage unit 15 can be charged to the maximum, the regenerative power can be effectively utilized to the maximum, and the efficiency of the entire vehicle can be improved.

  Further, by performing the switching of the switch 29 by determining whether the motor 37 is in the regenerative operation or the power running operation (S17) before the operation of the power converter 36, the switching can be performed in a state where the current flowing through the switch 29 is approximately 0A. Become. Therefore, since the switch 29 is not switched in the state where the charging current is flowing as in the conventional case, the reliability of the switch 29 is improved.

  The operation of the power supply device 11 described so far is summarized as follows. The control circuit 39 connects the switch 29 to the battery 13 side when the motor 37 is performing regenerative operation, and connects the switch 29 to the series circuit 16 side when the motor 37 is performing power running operation. If the power storage unit 15 is discharged by the power running operation, the DC / DC converter 17 charges the power storage unit 15 with the discharge.

  Note that the power storage unit 15 can be charged by the DC / DC converter 17 only to the power storage unit 15. Therefore, charging the power storage unit 15 during the regenerative operation of the motor 37 is efficient because the braking energy can be used. However, when the motor 37 is in a power running operation under a light load condition, or when the motor 37 is stopped, etc. The power storage unit 15 may be charged. By operating in this way, after the power storage unit 15 is discharged, it is possible to charge as soon as possible to prepare for the next high load power running operation. However, in this case, since the power storage unit 15 is charged with the power of the battery 13, the power storage unit 15 may be charged when the amount of power of the battery 13 is sufficient.

  With the above configuration and operation, it is possible to realize the power supply device 11 that can supply a stable high voltage and simultaneously satisfy high reliability and high efficiency with a simple configuration.

(Embodiment 2)
FIG. 3 is a block circuit diagram of the power supply apparatus according to Embodiment 2 of the present invention. FIG. 4 is a flowchart showing the operation of the power supply apparatus according to Embodiment 2 of the present invention. In FIG. 3, the thick line indicates the power system wiring, and the thin line indicates the signal system wiring. Moreover, in this Embodiment 2, the case where a power supply device is applied to an idling stop vehicle is demonstrated.

  3, the same components as those in FIG. 1 of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. That is, the structural features of the second embodiment are as follows.

  1) A capacitor 51 having excellent rapid charge / discharge characteristics was used as the power storage unit. As a result, when the engine is restarted after idling stop, it is possible to sufficiently supply a steep large current required for powering the motor 37. In the second embodiment, a large-capacity electric double layer capacitor is used as the capacitor 51.

  2) A diode 53 was connected in parallel with the capacitor 51. The connection direction is such that the anode is on the battery 13 side as shown in FIG. Thereby, for example, it is possible to prevent application of a reverse voltage to the power storage unit due to a large current continuously flowing without completing engine restart normally.

  3) The state detection means 55 is connected to the battery 13. Further, a temperature sensor 57 is disposed in the vicinity of the battery 13 so that the output of the temperature sensor 57 is input to the state detection means 55. The state detection means 55 obtains the state of charge and deterioration from the voltage-current characteristics of the battery 13 and the temperature from the temperature sensor 57, respectively, and transmits it to the control circuit 39 as the state signal SOH of the battery 13. Thereby, it is possible to perform control to change the charging voltage of the capacitor 51 according to the state of the battery 13.

  Other configurations are the same as those in FIG.

  Next, the operation of the power supply device according to the second embodiment will be described with reference to FIG. In FIG. 4, the same operations as those in FIG. 2 of the first embodiment are denoted by the same step numbers, detailed description thereof is omitted, and different operations will be described. 2 is changed to a capacitor in FIG.

  In FIG. 4, the initial charging operation of the capacitor 51 shown from S11 to S16 is the same as FIG. After S16, the control circuit 39 determines whether or not the vehicle performs idling stop. The charge state of the capacitor 51 is one of the determination factors, but it is determined whether or not to stop idling based on various determination factors such as the charge state of the battery 13, the engine temperature, and the stop state of the vehicle (S50). Some of these determination elements are obtained from the vehicle control circuit.

  When the idling stop is performed (Yes in S50), the engine of the vehicle is stopped and the motor 37 is also stopped. During this time, the connection of the switch 29 is switched to the series circuit 16 of the battery 13 and the capacitor 51 (S53). Note that power is supplied from the battery 13 to the load 25 while the engine is stopped.

  Thereafter, the vehicle-side control circuit restarts the engine based on a determination factor such as the driver releasing the brake. The engine is restarted by the power running operation of the motor 37. At this time, the motor 37 is supplied with power from the series circuit 16 of the battery 13 and the capacitor 51 via the power converter 36. Therefore, since a voltage higher than that of the battery 13 alone can be applied, the driving ability of the motor 37 is improved, and the restart time of the engine can be shortened.

  The control circuit 39 determines that the engine is started (S54). If the engine is not started (No in S54), the control circuit 39 returns to S54 until the engine is started. When the engine is started (Yes in S54), the control circuit 39 switches the switch 29 to the battery 13 side (S55). After the engine is started, the motor 37 is in a regenerative operation, and this regenerative power is supplied to the battery 13 and supplied to the load 25. Thereafter, the process returns to S50. At this time, since the engine is started, it is not in the idling stop state in S50 (No in S50). Accordingly, since the capacitor 51 is also discharged when the engine is started, the control circuit 39 determines the power of the capacitor 51 (S57). If the power is insufficient (No in S57), the DC / DC converter 17 causes the capacitor 51 to be discharged. 51 is charged (S59). Thereafter, the process returns to S57.

  When the power of the capacitor 51 is sufficient (Yes in S57), the process returns to the idling stop determination (S50) again.

  When the capacitor 51 is charged in S59, the control circuit 39 reads the temperature, charge state, and deterioration state of the battery 13 from the state detection means 55 of the battery 13, so that the charge voltage of the capacitor 51 according to the state of the battery 13 is read. Control to change. Specifically, the control is performed as follows. When the engine is restarted, a large current flows through the motor 37, which causes a voltage drop of the battery 13. The voltage drop width is determined by the current internal resistance value of the battery 13. Therefore, the voltage drop width is obtained based on the information of the internal resistance value estimated from the temperature, the charging state, and the deterioration state from the state detecting means 55, and the charging voltage of the capacitor 51 necessary to compensate for it is determined. For example, as the internal resistance value increases, the voltage drop width also increases, and accordingly, the charging voltage of the capacitor 51 is determined to be higher. Since the capacitor 51 is charged in this way, stable power can be supplied even when the internal resistance value gradually increases due to the deterioration of the battery 13 or the internal resistance value fluctuates due to a change in temperature. Stable restartability can also be obtained when the motor 37 is powered and restarts the engine.

  With such an operation, even if the power supply device 11 is applied to an idling stop vehicle, a stable high voltage can be supplied, so that the engine can be restarted at high speed.

  In the second embodiment, after the motor 37 is in the power running operation, the electric power discharged from the capacitor 51 is immediately charged to prepare for the next idling stop. However, this is the same as in the first embodiment. In addition, the capacitor 51 may be preferentially charged when the motor 37 performs the regenerative operation. Thereby, the highly efficient power supply device 11 is realizable.

  Moreover, it is good also as a structure which charges the capacitor | condenser 51 more electric power than the electric power required at the time of the power running operation of the motor 37 at the time of regenerative operation. Thereby, more regenerative electric power can be charged to the capacitor 51, and efficiency improves.

  In this case, even if the motor 37 performs a power running operation, power remains in the capacitor 51. Therefore, after the capacitor 51 is charged by the DC / DC converter 17, and when the motor 37 is not performing a regenerative operation. The stored power in the capacitor 51 may be discharged to the battery 13 by the DC / DC converter 17. Accordingly, since the generated power from the motor 37 is not required during the discharge of the accumulated power of the capacitor 51, the burden on the engine can be reduced and high efficiency can be obtained. Capacitor 51 is discharged to a voltage necessary for powering operation of motor 37. This voltage is determined based on the information output from the state detection means 55 of the battery 13 as described above.

  In the second embodiment, a relay having a three-terminal structure is used as the switch 29. However, two relays having a two-terminal structure may be combined. Thereby, especially when the current flowing through the switch 29 during powering operation is several times larger than the current flowing during regenerative operation as in an idling stop vehicle, the switch 29 corresponding to each current capacity can be selected. Specifically, for example, if the current during power running is 600 A and the current during regenerative operation is 100 A, the first switch connected between the series circuit 16 and the power converter 36 has a current capacity of about 600 A. The second switch connected between the battery 13 and the power converter 36 may have a current capacity of about 100A. As a result, an optimum switch configuration can be achieved, and the reliability of the switch 29 is increased.

  With the above configuration and operation, it is possible to realize the power supply device 11 that can supply a stable high voltage and satisfy high reliability and high efficiency simultaneously with a simple configuration even when applied to an idling stop vehicle.

  In the second embodiment, an electric double layer capacitor is used as the capacitor 51, but this may be another capacitor such as an electrochemical capacitor.

(Embodiment 3)
FIG. 5 is a block circuit diagram of the power supply device according to Embodiment 3 of the present invention during motor regeneration and non-operation. FIG. 6 is a block circuit diagram of the power supply device according to Embodiment 3 of the present invention during motor power running. 5 and 6, the thick line indicates the power system wiring, and the thin line indicates the signal system wiring. Also in the third embodiment, a case where the power supply device is applied to an idling stop vehicle will be described.

  5 and 6, the same components as those in FIG. 1 of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. That is, the structural features of the third embodiment are as follows.

  1) A switch 61 that is electrically connected to the input terminal 19 and the output terminal 21 of the DC / DC converter 17, the power storage unit 15, and the load 25 and is also electrically connected to the control circuit 39 is provided.

  2) As in the second embodiment, the power storage unit 15 is composed of an electric double layer capacitor.

  Other configurations are the same as those in FIG.

  Here, the detailed configuration of the switch 61 will be described below.

  With the above-described connection, the switch 61 electrically connects or disconnects the load 25 and the battery 13, and the output terminal 21 of the DC / DC converter 17 is connected to the power storage unit 15 or the load 25. It is comprised from the 2nd switch 65 electrically connected to either. All of these used relays.

  The first switch 63 and the second switch 65 are connected to the control circuit 39 by signal system wiring, and the first switch 63 and the second switch 65 are respectively received by the first switch signal SW1 and the second switch signal SW2 from the control circuit 39. And the state of the second switch 65 is switched. Thus, for example, as shown in FIG. 5, when the first switch 63 is turned on and the second switch 65 is switched to the power storage unit 15 side in the switch 61, the power of the battery 13 is supplied to the load 25. In addition to being supplied, the power of the battery 13 can be charged in the power storage unit 15 by operating the DC / DC converter 17. Further, as shown in FIG. 6, in the switch 61, when the first switch 63 is off and the second switch 65 is switched to the load 25 side, the DC / DC converter 17 is operated to operate the battery. The voltage 13 can be boosted and stabilized and supplied to the load 25.

  Next, the operation that characterizes the third embodiment will be specifically described. The operations not described here are the same as those in the first embodiment.

  First, the normal traveling time of the vehicle will be described. In this case, the switch 61 is in the state shown in FIG. The switch 29 is also switched to the second terminal 33 as shown in FIG. Here, the motor 37 performs a power running operation for restarting the engine after idling stop and a regenerative operation for generating regenerative power at the time of deceleration. During normal traveling, the motor 37 generates power by the engine torque. . Therefore, power is supplied to the load 25 and the battery 13 by setting the state of the switch 61 shown in FIG. In this case, since power is supplied from the battery 13 to the load 25 without going through the DC / DC converter 17, there is no loss due to the DC / DC converter 17, and high efficiency can be achieved.

  Next, the operation during vehicle deceleration will be described. When the control circuit 39 receives from the vehicle-side control circuit that the vehicle is decelerating by the data signal data, the control circuit 39 boosts the voltage of the battery 13 and effectively stores the regenerative power generated by the motor 37. The DC / DC converter 17 is controlled so as to be charged. At the time of power generation including the regenerative operation of the motor 37, the voltage of the battery 13 becomes equal to the output voltage of the power converter 36. Therefore, the output voltage generated by the regeneration is substantially boosted to charge the power storage unit 15. It will be. Further, at this time, since the first switch 63 is on, the regenerative power is also directly supplied to the load 25. For these reasons, the regenerative power generated by braking is charged to the battery 13 and the power storage unit 15 and also supplied to the load 25. Therefore, the regenerative power can be used effectively, and the efficiency of the vehicle can be improved.

  Thereafter, even when the vehicle stops and enters an idling stop state, the state of the switch 29 and the switch 61 remains as shown in FIG. Therefore, the power of the battery 13 is supplied to the load 25 while idling is stopped.

  Next, the operation when the idling stop is completed and the vehicle starts to travel again will be described. When the vehicle-side control circuit detects that the driver has switched from the brake pedal to the accelerator pedal, the information is transmitted to the control circuit 39 as the data signal data. In response to this, the control circuit 39 immediately switches the switch 29 to the first terminal 31 side, turns off the first switch 63, and switches the second switch 65 to the load 25 side, as shown in FIG. In this state, the control circuit 39 controls the power converter 36 to power-operate the motor 37. As a result, the engine restarts. At this time, the total voltage of the battery 13 and the power storage unit 15 is applied to the motor 37, and the motor 37 is driven by the electric power of both. Therefore, even if a large current flows immediately after driving the motor 37, the power supply from the power storage unit 15 is performed, so that the voltage drop of the battery 13 can be suppressed. Further, since it can be driven at a high voltage, the current flowing through the motor 37 can be reduced.

  However, even if the power storage unit 15 suppresses the voltage drop of the battery 13, a slight reduction still occurs. Accordingly, there is a possibility that the operation of the load 25 having a narrow voltage fluctuation tolerance range becomes unstable or stops. Therefore, in the third embodiment, the control circuit 39 controls the DC / DC converter 17 during the power running operation of the motor 37 to boost the lowered voltage of the battery 13, thereby stabilizing the voltage of the output terminal 21. Like to do. As a result, since the stable voltage is supplied to the load 25 even during the power running operation of the motor 37, the load 25 can continue normal operation.

  As described above, in the first and second embodiments, the DC / DC converter 17 is used only for charging the power storage unit 15, but in the third embodiment, the DC / DC converter 17 in the first and second embodiments is used. Since it is also used to stabilize the voltage of the battery 13 supplied to the load 25 during the power running operation of the motor 37 that is not used, the DC / DC converter 17 has a simple circuit configuration in which only the switch 61 is added. Can be effectively utilized.

  When the restart of the engine is completed, the control circuit 39 returns the switch 29 and the switch 61 to the state shown in FIG. Thereafter, the above operation is repeated.

  Note that the switch 61 is controlled so as not to be in a state other than the state described above. That is, if the switch 61 is in the state of FIG. 5 and the first switch 63 is turned off, the power supply to the load 25 is stopped. When the switch 61 is in the state shown in FIG. 5 and the second switch 65 is switched to the load 25 side, the input terminal 19 and the output terminal 21 of the DC / DC converter 17 are short-circuited, and the power storage unit 15 is charged. Can not be. Therefore, the control circuit 39 controls the switch 61 so as not to enter these states.

  The operations that characterize the above are summarized as follows. When the motor 37 is performing a regenerative operation, the control circuit 39 connects the battery 13 to the load 25 and connects the output terminal 21 to the power storage unit 15 as shown in FIG. The DC / DC converter 17 is controlled so as to charge the power storage unit 15 by boosting the voltage of the battery 13. When the motor 37 is performing a power running operation, the control circuit 39 switches the switch 61 so that the output terminal 21 of the DC / DC converter 17 is connected to the load 25, stabilizes the voltage of the battery 13, and loads the load. The DC / DC converter 17 is controlled so as to be supplied to 25.

  With the above configuration and operation, stable high voltage supply to the motor 37, high reliability and high efficiency can be simultaneously satisfied with a simple configuration, and a stable voltage is applied to the load 25 even during powering operation of the motor 37. Can be realized.

  In the third embodiment, the switching device 61 is constituted by a relay, but this may be constituted by a combination of semiconductor switches. Thereby, since there is no mechanical contact portion, high reliability can be obtained. However, in the case of the load 25 that consumes a large current, a loss occurs in the semiconductor switch. Therefore, the optimum one may be selected as appropriate according to the required current capacity.

  In the third embodiment, a relay that electrically connects or disconnects the load 25 and the battery 13 is used as the first switch 63, but this has a cathode on the load 25 side and a battery on the battery 13 side. A diode having anodes connected thereto may be used. In this case, the battery 13 and the load 25 cannot be electrically disconnected completely. However, since the operation is limited to the operation of the first switch 63 and the second switch 65 as described above, the first switch 63 is connected to the diode. Can be replaced. As a result, the above-described high reliability is advantageous, and control of the control circuit 39 is facilitated. However, since a loss due to a voltage drop occurs in the diode, the diode may be appropriately selected if the current consumption of the load 25 is small, and the relay may be appropriately selected if a large current is necessary.

  In the first to third embodiments, a relay is used for the switch 29. This is a switch that can switch between the first terminal 31 and the second terminal 33 by a switching signal SW from the control circuit 39, for example, the above-described one. As described above, a semiconductor switch may be used.

  In the first to third embodiments, the case where the power supply device 11 is applied to a hybrid vehicle or an idling stop vehicle has been described. However, the present invention is not limited thereto, and can be applied to an electric vehicle, a fuel cell vehicle, and the like. Furthermore, the present invention is not limited to a vehicle, and can also be applied as a motor drive power supply device such as an elevator or a crane.

  The power supply apparatus according to the present invention can reduce a voltage drop and supply a stable high voltage, and thus is particularly useful as a power supply apparatus for a fuel economy improving vehicle that performs idling stop or braking force regeneration.

1 is a block circuit diagram of a power supply device according to Embodiment 1 of the present invention. The flowchart which shows operation | movement of the power supply device in Embodiment 1 of this invention. Block circuit diagram of a power supply apparatus according to Embodiment 2 of the present invention The flowchart which shows operation | movement of the power supply device in Embodiment 2 of this invention. Block circuit diagram of the power supply device according to Embodiment 3 of the present invention during motor regeneration and non-operation Block circuit diagram at the time of motor power running of the power supply device in Embodiment 3 of the present invention Block diagram of a conventional power supply

DESCRIPTION OF SYMBOLS 11 Power supply device 13 Battery 15 Power storage part 16 Series circuit 17 DC / DC converter 29 Switch 36 Power converter 37 Motor 39 Control circuit 51 Capacitor 53 Diode 55 State detection means 61 Switch 63 First switch 65 Second switch

Claims (9)

Battery,
A power storage unit connected in series to the battery;
A DC / DC converter connected to charge and discharge the power storage unit using the battery as an input source;
A motor that performs power running operation and generates power by regenerative operation;
A power converter connected to the motor for supplying power during the power running operation of the motor and converting regenerative power during the regenerative operation;
A switch that switches the connection to the power converter to either one of the battery and the series circuit of the power storage unit or only the battery;
A control circuit connected to the DC / DC converter, the switch, and the power converter;
When the motor is performing the regenerative operation, connect the switch to the battery side,
When the motor is performing the power running operation, the switch is connected to the series circuit side,
A power supply device, wherein a discharge of the power storage unit is charged by the DC / DC converter. The power supply device according to claim 1, wherein the power storage unit is charged by the DC / DC converter at least when the motor performs the regenerative operation. The power supply apparatus according to claim 1, wherein the power storage unit includes a capacitor. The power supply device according to claim 3, wherein a diode is connected in parallel with the capacitor. The capacitor stored in the capacitor is discharged to the battery side by the DC / DC converter after the capacitor is charged by the DC / DC converter and when the motor is not performing the regenerative operation. Item 4. The power supply device according to Item 3. Having a configuration in which a state detection means is connected to the battery;
The power supply apparatus according to claim 3, wherein the control circuit changes a charging voltage of the capacitor according to a state of the battery output from the state detection unit. The switch includes a first switch connected between the series circuit and the power converter;
The power supply device according to claim 1, comprising a second switch connected between the battery and the power converter. The DC / DC converter includes an input terminal and an output terminal, a power storage unit, and a switch electrically connected to the load and also electrically connected to the control circuit,
When the motor is performing the regenerative operation, the control circuit connects the battery to the load and switches the switch so as to connect the output terminal to the power storage unit. Controlling the DC / DC converter to boost the voltage and charge the power storage unit;
When the motor is in a power running operation, the switch is switched so that the output terminal of the DC / DC converter is connected to the load so that the voltage of the battery is stabilized and supplied to the load. The power supply apparatus according to claim 1, wherein the DC / DC converter is controlled. The switch is a first switch that electrically connects or disconnects the load and the battery;
The power supply apparatus according to claim 8, further comprising: a second switch that electrically connects the output terminal of the DC / DC converter to either the power storage unit or the load.

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