JP3211323B2 - Charging device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device for charging a storage battery mounted on, for example, an electric vehicle.

[0002]

2. Description of the Related Art In an electric vehicle, a motor is used as a motor, a secondary battery (rechargeable battery) is mounted on a power source thereof, and motor control is performed by a motor control device. For this reason, an electric vehicle requires a charging device for charging a mounted storage battery, unlike supplying fuel such as gasoline required for a conventional vehicle using an internal combustion engine as a prime mover.

FIG. 13 shows a conventional charging device for an electric vehicle. 1 is a charging device, and 2 is an electric vehicle. A charging cable 3 is connected to output terminals A and B of the charging device 1, and the other end of the charging cable 3 is connected to input terminals A ′ and B ′ of the electric vehicle 2, so that the charging cable 3 is mounted on the electric vehicle 2. The storage battery 4 is charged.

[0004] In the charging device 1, the switch 6
, And the AC power is converted into DC power by the rectifier 7, and a DC output is obtained at the output terminals A and B via the switch 8. The control unit 9, which configures the charger in combination with the rectifier 7, controls the output current and voltage of the rectifier 7 based on the DC current and DC voltage detected by the current detection unit 10 and the voltage detection unit 11, and controls the constant current. The storage battery 4 is charged by a charging method such as a constant voltage method. As a similar known example, there is JP-A-62-166710.

[0005] The charging device 1 is required to be able to charge the storage battery 4 in a short time in view of the spread and maintenance of electric vehicles. Improvements and researches are underway.

[0006]

As described above, the charging device is provided with a large current and a high voltage for charging the storage battery of the electric vehicle so that rapid charging can be performed with the same charging time as gasoline refueling time at a gas station. Is achieved.

For this reason, the charging device requires high power energy (for example, 100 kW to 200 kW) in a short time (for example, 10 to 20 minutes) at the time of charging, and its power receiving equipment has a power receiving capacity of several hundred amperes. Need. In addition, if the charging devices are arranged in various places and the charging operations are performed at random due to the spread of electric vehicles, the power transmission and distribution equipment will have a short-time high load that occurs randomly from the power transmission and distribution equipment side. In order to cope with this, the transmission and distribution capacity must be constantly increased in spite of the short-time high load, and the equipment efficiency deteriorates.

[0008] It is an object of the present invention to provide a charging apparatus which enables rapid charging of an electric vehicle while leveling the load on the AC power supply side, and further increases the equipment efficiency of the apparatus itself.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a rectifier for rectifying an alternating current from a power receiving facility, a secondary battery for the facility, a low-current charging for the secondary battery and the secondary battery. A charger that controls the discharge from the secondary battery, and always controls the DC output from the rectifier to the DC input of the charger and switches the DC output of the charger to the charging input to the secondary battery, A switching control circuit for switching the DC output of the charger to the DC input of the secondary battery and for controlling the switching of the DC output of the charger to the DC input of the secondary battery when charging is requested from the secondary battery of the load; It is characterized by having.

Further, the present invention provides an AC / DC step-up conversion control for an AC input and a DC input for a DC input by using a facility secondary battery and a power conversion circuit having a bridge configuration of a reactor and a semiconductor switch provided at an input terminal. A charger for performing DC / DC step-up conversion control, and an AC current from a power receiving facility is always used as an AC input of the charger, and a DC output by the AC / DC step-up conversion control of the charger is supplied to the facility secondary battery. The charging control is switched to the charging input, and when charging is requested from the secondary battery on the load side, the DC power of the secondary battery is changed to the DC input of the charger, and the DC output by the DC / DC boost conversion control of the charger is changed. And a switching control circuit for performing switching control to charge input to the secondary battery.

Further, the present invention provides an AC / DC step-up conversion control for an AC input and a DC input for a DC input by using a facility secondary battery and a power conversion circuit having a bridge configuration of a reactor and a semiconductor switch at an input end. A charger that performs DC / DC step-up conversion control, a switch circuit having a step-down chopper control function of the DC output of the facility secondary battery, and an AC current from a power receiving facility that is always used as an AC input of the charger. The DC output by the AC / DC step-up conversion control of the charger is controlled to be switched to the charging input to the facility secondary battery, and the DC power of the secondary battery is switched when the charging from the secondary battery on the load side is requested. A switching system which takes out by the chopper control of the circuit, makes the DC input of the charger, and controls the DC output by the DC / DC boosting power conversion control of the charger to the charging input to the secondary battery. Characterized in that a circuit.

Further, the present invention provides a cascade connection of a reactor and a power conversion circuit having a bridge configuration of a semiconductor switch, wherein an AC input from the reactor is applied to the power conversion circuit by AC / DC step-up conversion control. A charger that obtains a DC output and obtains a DC output on the reactor side by DC / DC step-down conversion control with respect to a DC input from the power conversion circuit, and is connected to a DC input / output terminal of a power conversion circuit of the charger. And a secondary battery for equipment that performs direct current charging and discharging, and always uses an alternating current from the power receiving equipment as an input on the reactor side of the charger, and switches the charger to AC / DC conversion control, thereby controlling the load side. A switching control circuit that switches the charger to DC / DC conversion control when charging is requested from the secondary battery and switches the DC output from the reactor to the charging input to the secondary battery of the electric vehicle. Characterized by comprising and.

Further, the present invention is configured such that a cascade connection is made between a reactor and a power conversion circuit having a bridge configuration of a semiconductor switch, and an AC input from the reactor side is subjected to AC / DC step-up conversion control so that DC power is supplied to the power conversion circuit side. Get the output,
A charger for obtaining a DC output on the reactor side by DC / DC step-down conversion control with respect to a DC input from the power conversion circuit side; and a DC charge / discharge connected to the DC input / output of the power conversion circuit of the charger. And a switch circuit having a step-up chopper control function of a DC output from the reactor side of the charger, and an AC current from the power receiving facility is always input to the reactor side of the charger. The charger is switched to AC / DC conversion control, the charger is switched to DC / DC conversion control when charging is requested from the secondary battery on the load side, and the DC output from the reactor is taken out by the chopper control of the switch circuit. A switching control circuit for switching to a charging input to a secondary battery of the electric vehicle.

The present invention also provides a small current capacity AC / DC converter for converting AC power from a power receiving facility into DC power.
A secondary battery that is floatingly charged with DC power from the AC / DC converter, and a DC / DC that obtains DC power from the secondary battery and the AC / DC converter and charges the load-side secondary battery with a large current.
A DC converter, and the DC / DC converter further comprises output limiting means for limiting a charging output to a rated output of the AC / DC converter when the secondary battery is at the end of discharging. And

[0015]

According to the first aspect of the present invention, the AC power taken from the power receiving facility is converted into DC power by the rectifier, and the DC power is charged to the secondary battery for the facility by the charger. At the time of request, the DC power from the facility secondary battery is taken out by the charger, and the load secondary battery is charged. As a result, the charging device becomes a low-load and stable load by constantly charging the power receiving equipment and the like, and takes out a quick charging current from the equipment secondary battery for the load secondary battery. In addition, the efficiency of the equipment is enhanced by sharing the charger for charging the equipment secondary battery and for charging the load secondary battery.

According to a second aspect of the present invention, the secondary battery for the facility is charged by the AC / DC step-up conversion control of the charger with the AC power normally taken from the power receiving facility side, and the charging from the load-side secondary battery of an electric vehicle or the like is performed. When required, the DC power from the facility secondary battery is taken out by the DC / DC boost conversion control of the charger, and the load-side secondary battery is rapidly charged.

According to a third aspect of the present invention, the input from the facility secondary battery to the charger is chopped by a switch circuit to reduce the output from the secondary battery, thereby increasing or decreasing the charging power for an electric vehicle or the like. Can be output, and charging can be performed even when the voltage of a secondary battery such as an electric vehicle is higher or lower than the voltage of the facility secondary battery.

According to a fourth aspect of the present invention, the secondary battery for the facility is charged by the AC / DC step-up conversion control of the charger with the AC power taken from the power receiving facility at all times. DC power from the secondary battery is taken out by DC / DC step-down conversion control of the charger, and the secondary battery of an electric vehicle or the like is rapidly charged.

According to a fifth aspect of the present invention, the output from the charger is boosted by chopping the input from the reactor of the charger to the secondary battery on the load side by a switch circuit, so that the output of the secondary battery is boosted or reduced. Stepped-down charging power can be output, and charging can be performed even when the voltage of the load-side secondary battery is higher or lower than the voltage of the facility secondary battery.
According to a sixth aspect of the present invention, a small current alternating current is taken in from an electric power receiving facility by an AC / DC converter, and the secondary battery is charged with the small current DC power. A large current is taken out of the secondary battery by a container and is rapidly charged. By limiting the output of the DC / DC converter to the rated output of the AC / DC converter at the end of discharge of the secondary battery, the charging function is ensured while preventing overdischarge.

[0020]

FIG. 1 is a block diagram showing an embodiment of the present invention, in which the present invention is applied to a charging device for an electric vehicle. The charging device 21 takes in AC power from a commercial AC power supply 22 through a power receiving facility including a circuit breaker 23 and the like. The charging device 21 includes a low-current-capacity rectifier 24 that rectifies an alternating current from the power receiving facility, a large-capacity storage battery 25, and a charge that controls low-current charging of the storage battery 25 and large-current discharge from the storage battery 25. Mode in which the output of the rectifier 24 and the output of the rectifier 24 are input to the charger 26 and the output is the charging input of the storage battery 25, and the storage battery 25 is the DC input of the charger 26 and the output is the charging input of the storage battery 4 of the electric vehicle 2. And a changeover switch 27 that controls to switch between the charging mode and the charging mode.

The changeover switch 27 serves as an output section of a changeover control circuit.
And a mode command for switching between low current control in the accumulation mode and large current control in the charging mode.

In the above configuration, the changeover switch 27 is normally switched to the storage mode in which the illustrated state is set, the AC current from the power receiving facility is rectified by the rectifier 24, and this DC power is stored in the storage battery 25 through the charger 26. Charge with low current.

In the charging mode in response to a charging request from the electric vehicle 2, the changeover switch 27 is switched from the state shown in the drawing to take out a large current of DC power from the storage battery 25 to the charger 26. High-current charging, that is, rapid charging.

Accordingly, the charging device 21 reserves a large amount of power required for rapidly charging the storage battery 4 of the electric vehicle 2 as the storage power of the storage battery 25, and this stored power is reduced by the rectifier 24 and the charger 26 to a low current. To accumulate over time.

As a result, the charging device 21 has a rapid charging capability for the electric vehicle, and has a substantially constant low load on the power receiving equipment and the commercial AC power supply 22 regardless of day and night.

The charger 26 is used as a current and voltage control means in both modes of charging the storage battery 25 and discharging from the storage battery 25 to the electric vehicle 2, thereby charging the storage battery for equipment and the electric vehicle. It is not necessary to provide a charger for charging the storage battery, thereby improving facility efficiency.

In the embodiment, the rectifier 24 is a low-current AC / DC converter, is realized with a low-current capacity circuit configuration, and rarely causes a cost increase of the charging device.

FIG. 2 shows a specific circuit diagram of the present embodiment.
The rectifier 24 includes a diode D ₁ and a smoothing capacitor C _1. The current capacity of the diode and the capacitance of the capacitor may be any as long as they have a low current rectifying ability in the accumulation mode. Although a single-phase half-wave rectifier circuit is shown, a single-phase full-wave
A phase full-wave rectifier circuit may be used.

The changeover switch 27 constitutes a changeover control circuit together with the control circuit 27A. The control circuit 27A changes over the changeover switch 27 in response to a mode changeover command (a charge request from the electric vehicle) and sends a current mode signal to the charger 26. give.

The charger 21 has a DC chopper configuration,
In the accumulation mode, the transistor 28 as a switch element
Is turned on / off (chopper control), and during the ON period, the DC current from the rectifier 24 is supplied to the charging current through the path of the transistor 28 → DC reactor 29 → rectifier diode 30 → storage battery 25. Flywheel diode 31 → DC reactor 29 →
A charging current is supplied through a path from the diode 30 to the storage battery 25.

In this accumulation mode, a step-down chopper operation is performed in which the output voltage of the rectifier 24 is stepped down, and the average current is controlled by the on / off ratio of the transistor 28 by the chopper control circuit 32. In this control, the detected current from the current detector 33 is used as a feedback signal. When the charging of the battery 25 reaches the end voltage, the chopper stop control is performed by the voltage detector 34 detecting the voltage.

On the other hand, in the charging mode of the charger 21, the transistors 35 and 28 as switching elements are simultaneously turned on.
Off control is performed. When the transistor 35 is turned on at the same time as the transistor 28 is turned on, the storage battery 25
DC current from transistor 28 to DC reactor 2
9 → a short-circuit current flows through the path of the transistor 35, and the DC reactor 29 → the diode 30 → the storage battery 4 → the diode 3 by turning off the transistors 28 and 35 at the same time.
A large charging current is supplied to the storage battery 4 through the path 1.

In this charging mode, a boost chopper operation is performed in which the voltage of the storage battery 25 is boosted, and the average current is controlled by the on / off ratio of the transistors 28 and 35 by the chopper control circuit 32. Also in this case, the same current detector 33 is used for detecting and controlling the charging current, and similarly, the voltage detector 34 is used for detecting and controlling the charging end voltage.

Accordingly, the charger 21 functions as a step-up / step-down chopper, and the voltage of the AC power supply and the storage battery 4 of the electric vehicle 2
In addition, a great degree of freedom can be given to the difference in the voltage of the storage battery 25 for the facility, and it is possible to easily cope with the difference in the voltage type of the AC power supply and the difference in the storage battery voltage of the electric vehicle. .

FIG. 3 is a block diagram showing another embodiment of the present invention, in which the present invention is applied to a charging device for an electric vehicle. The charging device 21 takes in AC power from a commercial AC power supply 22 through power receiving equipment including a circuit breaker 23 and the like. In the charging device 36, a charger 39 is configured by a power conversion circuit 38 having a bridge configuration of a reactor 37 provided at an input end and a semiconductor switch. The charger 39 has a low-current AC / DC step-up conversion control function and a large-current DC / DC step-up conversion control function, and performs low-current charging and large-current discharging from the large-capacity facility storage battery 40. Control.

The charging device 36 has a storage mode in which the AC input from the power receiving equipment is used as an input to the charger 39 and the output is used as a charging input for the storage battery 40.
And a charge switch 41 for switching between a direct current input and a charge mode in which the output is a charge input of the storage battery 4 of the electric vehicle 2.

The changeover switch 41 serves as an output portion of a changeover control circuit, and when the mode is changed over, the input / output current of the charger 39 is controlled to a low-current AC / DC step-up conversion control in the accumulation mode, and to a large value in the charge mode. A mode command for switching between DC / DC step-up conversion control of current is given to charger 39.

In the above-described configuration, the changeover switch 41 is normally switched to the storage mode in which the illustrated state is set, and the alternating current from the power receiving equipment side is supplied to the storage battery 40 through the changeover switch 41, the reactor 37, and the power conversion circuit 38 to reduce the current. Charge it.

In the charging mode in response to a charging request from the electric vehicle 2, the changeover switch 41 is switched from the illustrated state, and the DC power of the storage battery 40 is taken out to the charger 39 comprising the reactor 37 and the power conversion circuit 38. The output charges the storage battery 4 of the electric vehicle 2 with a large current, that is, a quick charge.

Accordingly, the charging device 36 reserves a large amount of power required for rapidly charging the storage battery 4 of the electric vehicle 2 as the storage power of the storage battery 40, and this storage power is stored in the reactor 3
The battery is stored at low current for a long time by a charger 39 including a power conversion circuit 7 and a power conversion circuit 38.

As a result, the charging device 36 has a rapid charging capability for an electric vehicle, and has a substantially constant low load on the power receiving equipment and the commercial AC power supply 22 both day and night.

The charger 39 is used as both current and voltage control means in both modes of charging the storage battery 40 and discharging from the storage battery 40 to the electric vehicle 2 side, thereby charging the storage battery for equipment and the electric vehicle. It is not necessary to provide a charger for charging the storage battery, thereby improving facility efficiency. Further, since the charger 39 has both functions of AC / DC step-up conversion control and DC / DC step-up conversion control, a rectifier for temporarily converting AC from the AC power supply 22 side to DC is unnecessary, and the equipment efficiency is further improved. .

FIG. 4 shows a specific circuit diagram of the present embodiment.
Shown in a single-phase circuit. The power conversion circuit 38 includes transistors Tru, Trv, Trx, and Try as switch elements, and diodes Du, Dv, Dx, and Dy that are respectively anti-parallel to the transistors.
And a control circuit CN for turning on / off each transistor.
And T. 42 is a smoothing capacitor, 43
Is a voltage detector, and 44 is a current detector.

The control circuit CNT operates from the power receiving equipment to the storage battery 4.
In the accumulation mode in which charging to 0 is performed, PWM is applied to the main circuit.
Control to obtain AC / DC step-up conversion control,
In the charging mode from 0 to the storage battery 4 of the electric vehicle 2, DC / DC boost control is obtained by performing chopper control on the main circuit. In the current and voltage control in both modes, feedback control is performed based on detection signals of the current detector 44 and the voltage detector 43.

The changeover switch 41 constitutes a changeover control circuit together with the control circuit 41A. The control circuit 41A changes over the changeover switch 41 in response to a mode changeover command (a charge request from the electric vehicle), and sends a current mode signal to the charger 39. give.

The operation of the charger 39 in the accumulation mode will be described in detail below.

In this mode, the changeover switch 41 is in the state shown in the figure, and the transistors Tru, Trv, Trx, Tr
y is PWM controlled. In the PWM control, in a positive period in which the point A is positive with respect to the point B, first, a short-circuit current flows to the reactor 37 by turning on the transistor Trx, and thereafter, the transistor 37 is turned off to turn off the reactor 37.
Current is diode Du → switch 41 → storage battery 40 →
It flows along the path of the diode Dy and charges the storage battery 40.
Conversely, during the period when the point A is negative with respect to the point B, the storage battery 40 is charged when the transistor Try is turned on and then turned off.
The on / off of these transistors Trx and Try is PW
The control is performed at the carrier frequency of the M control, and the magnitude of the charging current is controlled by the modulation rate.

Next, in the charging mode, the changeover switch 41 is switched from the state shown in FIG.
rv, Trx, and Try are controlled by a boost chopper. In this chopper control, the positive electrode side of the storage battery 40 is added in parallel to the bridge connection through the reactor 41, and first, the transistors Trx and Try are turned on, a short-circuit current flows through the reactor 37, and then the transistors Trx and Try are turned off. Reactor 37 → Diode Du, D
A current flows through the route of v → storage battery 4 → storage battery 40, and the storage battery 4 is charged. At this time, the transistors Trx and Try
Is controlled by the flow rate of the chopper.

FIG. 5 is a block diagram showing another embodiment of the present invention. 3 differs from FIG. 3 in that a switch circuit 45 is provided on the input path from the equipment storage battery 40 to the reactor 37. The switch circuit 45 has a transistor Tr as a switch element and a flywheel diode D to obtain step-down chopper control, and steps down the voltage applied from the storage battery 40 to the reactor 37 in the charging mode by the on / off ratio of the transistor Tr.

The control of the charger 39 and the like in this embodiment is performed in the same manner as in FIG. 3, but the voltage of the storage battery 40 is reduced by the switch circuit 45 and applied to the charger 39. As a result, the charging device 36 can have a step-down chopper control function as well as the charging device 36 under the step-up chopper control, and can be charged even when the storage battery 4 of the electric vehicle 2 is lower than the storage battery 40, and the charging voltage can be reduced. Increase freedom.

A specific circuit diagram of this embodiment is shown in FIG.
Only the switch circuit 45 differs from that of FIG.
9 are the same. The chopper control of the switch circuit 45 is performed by the control circuit CNT of the charger.

FIG. 7 is a block diagram showing another embodiment of the present invention, in which the present invention is applied to a charging device for an electric vehicle. The charging device 46 takes in AC power from the commercial AC power supply 22 through power receiving equipment including the circuit breaker 23 and the like. In the charging device 46, a charger 49 is configured by a continuous connection of a reactor 47 provided at an input end and a power conversion circuit 48 having a bridge configuration of semiconductor switches. This charger 49
Has a bidirectional power conversion function of performing low-current AC / DC step-up conversion control on the AC input from the reactor 47 side and high-current DC / DC step-down conversion control on the DC input from the storage battery 50; It controls small-current charging and large-current discharging from the storage battery 50 for the large-capacity storage battery 50.

The charging device 46 has an accumulation mode in which an AC input from the power receiving equipment is used as an input to the charger 49 and an output thereof is used as a charging input for the storage battery 50.
And a changeover switch 51 for switching between a DC input and a charge mode in which the output is used as a charge input of the storage battery 4 of the electric vehicle 2.

The changeover switch 51 serves as an output section of a changeover control circuit.
The input / output current is supplied to the charger 49 with a mode command for switching between low-current AC / DC step-up conversion control in the accumulation mode and high-current DC / DC step-down conversion control in the charging mode.

In the above-described configuration, the changeover switch 51 is normally switched to the storage mode in which the illustrated state is set, and the alternating current from the power receiving equipment side is supplied to the storage battery 50 through the changeover switch 51, the reactor 47, and the power conversion circuit 48 to reduce the current. Charge it.

In the charging mode in response to a charging request from the electric vehicle 2, the changeover switch 51 is switched from the state shown in the drawing, and the DC power of the storage battery 50 is taken out to the reactor 47 side of the charger 49 including the power conversion circuit 48 and the reactor 47. The output of the charger charges the storage battery 4 of the electric vehicle 2 with a large current, that is, a quick charge.

Therefore, the charging device 46 secures a large amount of power required for rapidly charging the storage battery 4 of the electric vehicle 2 as the storage power of the storage battery 50, and this storage power is stored in the reactor 4
The battery is stored at a low current for a long time by a charger 49 including a power conversion circuit 7 and a power conversion circuit 48.

As a result, the charging device 46 has a rapid charging capability for electric vehicles, and has a substantially constant low load on the power receiving equipment and the commercial AC power supply 22 regardless of day or night.

The charger 49 has a bidirectional power conversion function in both modes of charging the storage battery 50 and discharging from the storage battery 50 to the electric vehicle 2, so that the battery for equipment charging and the charging of the storage battery of the electric vehicle are provided. It is not necessary to provide a charger for each device, and the changeover switch is required only on the reactor side, thereby improving facility efficiency. Further, the charger 49
Has both functions of AC / DC step-up conversion control and DC / DC step-up conversion control, so that a rectifier that once converts AC from the AC power supply 22 to DC is not required, and the equipment efficiency is further improved.

FIG. 8 shows a specific circuit diagram of this embodiment.
Shown in a single-phase circuit. Power conversion circuit 48, the transistor T _rU as a switch element, T _rV, T _rX, bridge connection constituting the switching circuit having T _rY therewith respectively antiparallel diodes _{D U, D V, D X} , and D _Y And a control circuit CNT for controlling ON / OFF of each transistor. 52 is a smoothing capacitor, 53 is a voltage detector,
54 is a current detector.

The control circuit CNT operates from the power receiving facility to the storage battery 5.
In the accumulation mode in which charging to 0 is performed, PWM is applied to the main circuit.
Control to obtain AC / DC step-up conversion control, and
In the charging mode from 0 to the storage battery 4 of the electric vehicle 2, DC / DC step-down control is obtained by performing chopper control on the main circuit. The current and voltage control in both modes is performed by detecting the current detector 54 and the voltage detectors 53 and 55, by detecting the voltage detector 53 when charging the battery 50, and by detecting the voltage detector 53 when charging the storage battery 4. Feedback control is performed by the detection of 55.

The changeover switch 51 constitutes a changeover control circuit together with the control circuit 51A. The control circuit 51A changes over the changeover switch 51 in response to a mode changeover command (a charge request from the electric vehicle), and sends a current mode signal to the charger 49. give.

The operation of the charger 49 in the accumulation mode will be described in detail below.

[0064] switch 51 is in the mode is in the illustrated state, the transistor _{T rU, T rV, T rX} , T rY the PW
M is controlled. The PWM control, A point passing a short-circuit current in the reactor 47 by first ON of the transistor T _rX is positive with positive periods for point B, the current of the reactor 47 by turning off the transistor T _rX after this diode D _U → storage battery 50 → diode D _Y flows on the route,
The storage battery 50 is charged. Conversely, during the period when the point A is negative with respect to the point B, the storage battery 50 is charged when the transistor _TrY is turned on and then turned off. The turning on and off of these transistors _TrX and _TrY are performed in a carrier cycle of PWM control, and the magnitude of the charging current is controlled by the modulation factor.

Next, in the charging mode, the changeover switch 51 is switched from the state shown in the figure, and the transistors _TrU , _TrV ,
_TrX and _TrY are controlled by a step-down chopper. This chopper control, the transistor T _rU, the positive electrode side of the battery 50 by turning on both the T _rV is added to the parallel reactor 47 flowing a charging current to the battery 4, and then the transistor T
By turning off _rU and _TrV , reactor 47 → storage battery 4
→ A charging current flows through the paths of the diodes D _X and D _Y to charge the storage battery 4. At this time, the on / off ratio of the transistors _TrU and _TrV is controlled by the _conduction rate of the chopper.

FIG. 9 is a block diagram showing another embodiment of the present invention. 7 differs from FIG. 7 in that a switch circuit 5 is provided in the charging path from the reactor 47 to the storage battery 4 of the electric vehicle 2.
6 is provided. The switch circuit 56 to obtain a step-up chopper control and a transistor T _r a blocking diode D as a switching element, turns on the transistor T _r to the voltage application to the reactor 47 in the charging mode, short-circuit current to the reactor 47 flushed, obtaining then the voltage output boosted by turning off the transistor T _r.

The control of the charger 49 and the like in this embodiment is performed in the same manner as in the case of FIG. 7, but the voltage of the storage battery 50 is boosted by the switch circuit 56 and is taken out to the electric vehicle 2. Thereby, the charger 49 can perform the step-down chopper control, but can also have the step-up chopper control function as the charging device 46, and can be charged even when the storage battery 4 of the electric vehicle 2 is higher than the storage battery 50. Increase freedom.

FIG. 10 shows a specific circuit diagram of this embodiment. The control of the charger 49 is the same except that the switch circuit 56 is different from that of FIG. The chopper control of the switch circuit 50 is performed by the control circuit CNT of the charger.

FIG. 11 is a block diagram showing another embodiment of the present invention, in which the present invention is applied to a charging device for an electric vehicle.
The charging device 57 is connected to the commercial AC power source 22 by the circuit breaker 23.
AC power is taken in through power receiving equipment composed of
The charging device 57 includes a small-current-capacity AC / DC converter 58 that converts AC power from the power receiving facility into DC power, and a storage battery 59 that is floatingly charged with the DC power from the converter 58.
And a DC / DC converter 60 that obtains DC power from the storage battery 59 and the converter 58 and charges the storage battery 4 of the electric vehicle 2 with a large current.

The AC / DC converter 58 has a DC output current controlled by a rectifier 61 and its control circuit 62. The current control is performed by a feedback control based on a set value of a current setter 63 and a detected value of a current transformer 64. Made in. Further, the current control is stopped when the charging of the storage battery 59 is performed to the end voltage. The end voltage of the floating charge and discharge of the storage battery 59 is detected by the voltage detector 65.

The DC / DC converter 60 includes a DC chopper 6
6 and its control circuit 67 control the output current.
In this current control, a set value of the current setter 68 (a large current set value for quick charging) or a set value of the setter 63 is given by switching control of the changeover switch circuit 69. The feedback control is performed based on the detected value of. Further, the current control is stopped as the charging end when the floating charging of the storage battery 4 of the electric vehicle 2 is performed to the final voltage. This voltage is detected by the voltage detector 71.

The changeover switch circuit 69 includes a voltage detector 65
Is switched by the detected voltage, and the set value of the current setting unit 68 is taken as the current set value until the voltage of the storage battery 59 decreases to the discharge end voltage. When the storage battery 59 decreases to the discharge end voltage, the current setting unit 63 To the set value.

The operation of the charging apparatus according to the present embodiment will be described in detail with reference to the waveform chart of FIG.

The AC / DC converter 58 includes a current setting unit 63
Give the low constant current output I ₁ by setting, in the normal floating charge storage battery 59 by the constant current-constant voltage method. When the storage battery 59 is charged to the charge end voltage V _MAX (time t _{1 in} FIG. 12), the output is stopped, and the storage battery 59 is stopped.
The attempt to maintain at all times the end-of-charge voltage V _MAX.

In the above-mentioned state, when the charging from the DC / DC converter 60 is started due to the charging request from the electric vehicle 2 (time t ₂ ), the DC / DC converter 60 turns on the current setting unit 6
Charging briefly T ₁ of the battery 4 with a large current I _H in accordance with 8 settings. The large electric power required at this time is mainly supplied from the storage battery 59, and the charging voltage of the storage battery 4 is changed to the charging end voltage V _S.
Is reached (time t ₃ ), charging is terminated.

At the end of charging of the storage battery 4 of the electric vehicle 2, the voltage of the storage battery 59 has dropped due to discharging, and the AC / DC converter 5 restores this voltage to the original charge termination voltage state.
The charging with the small current from 8 starts.

Accordingly, the charging device 57 secures a large amount of electric power necessary for rapidly charging the storage battery 4 of the electric vehicle 2 as the storage power of the storage battery 59. To accumulate over time. As a result, the charging device 57 has a rapid charging capability for the electric vehicle, and has a substantially constant low load on the power receiving facility and the commercial AC power supply 22 regardless of day or night.

Here, when there is a charging request from the next electric vehicle before the charging of the storage battery 59 is completed (FIG. 1).
2, at time t ₄ ), the DC / DC converter 60 performs rapid charging until the storage battery 59 reaches the discharge end voltage V _{MIN, and} when the storage battery 59 reaches the voltage (time t ₅ ), the changeover switch circuit 6
9 is switched to the set value of the current setting device 63 is performed until charging the charging completion of the battery 4 (time t ₆₎ by a lower current I _L to be set value from the DC-DC converter 60.

By this switching, the AC / DC converter 5
8 is limited by the output current I ₁ of the storage battery 5
The charging of the storage battery 4 of the electric vehicle 2 is completed while preventing the overdischarge of the battery 9. Also in this case, the charging device 57 has a constant low load on the power receiving equipment and the like.

Therefore, in this embodiment, the storage battery 4 of the electric vehicle 2 is rapidly charged by discharging from the storage battery 59 by the DC / DC converter, and the power of the storage battery 59 is received by the AC / DC converter.
It takes a relatively long time with a low current from the DC converter,
When the power storage of the storage battery 59 becomes insufficient, the battery is charged with a small current from the AC / DC converter.

Thus, the charging device 57 has a short-time rapid charging capability for an electric vehicle and a stable low load for a power receiving facility or the like. The load becomes stable when viewed from the side.
In addition, the storage battery 25 is protected from overcharge and overdischarge, and the reliability of the device is improved.

In the embodiment, the AC / DC converter 58 is a small-current power converter, is realized with a low-current-capacity circuit configuration, and rarely causes an increase in the cost of the charging device.

The storage battery 59 is always maintained in a good charge state, and when the storage battery 4 of the electric vehicle 2 needs to be replaced due to its life or the like, a part of the storage battery 59 is replaced as a substitute for the storage battery 4. And can be used as pool means for electric vehicle storage batteries.

[0084]

As described above, according to the present invention, DC power is normally obtained from an AC power source by a rectifier and a charger to constantly charge a storage battery for equipment, and the storage battery for an electric vehicle or the like is constantly charged. Since the load storage battery is charged by obtaining DC power from the storage battery by the charger at the time of the charging request, the load on the AC power supply can be smoothed by constantly charging the facility storage battery, and the With the capacity reduction and efficient use of power transmission and distribution equipment,
From the storage battery for equipment, a quick and easy charging service can be obtained by rapid charging of an electric vehicle or the like.

Further, according to the present invention, the charger can be used for controlling the constant charging of the storage battery for the facility and the rapid charging of the storage battery of the electric vehicle or the like from the storage battery, thereby improving the facility efficiency of the apparatus itself.

Further, in the present invention, the charger can be used for controlling the constant charging of the storage battery for equipment and the rapid charging of the storage battery of the electric vehicle or the like from the storage battery.
Since it has a DC conversion function and a DC / DC conversion function, a direct connection to an AC power supply eliminates the need for a rectifier therebetween, thereby greatly improving equipment efficiency.

Further, in the present invention, since a switch circuit having a step-down chopper control function is provided for charging the storage battery for an electric vehicle or the like from the storage battery for the installation, a high degree of freedom is provided in the magnitude relationship between the storage battery for the installation and the storage battery for the electric vehicle or the like. To increase the versatility of the charging device.

Further, in the present invention, the charger is a bidirectional power conversion circuit, and can be shared by one switch for controlling the regular charging of the storage battery for equipment and the rapid charging of the storage battery to the storage battery of an electric vehicle or the like. Since the charger has the functions of AC / DC conversion and DC / DC conversion, it is possible to obtain equipment directly connected to the AC power supply, eliminate the need for a rectifier between them, and increase equipment efficiency extremely.

Further, in the present invention, since a switch circuit having a boost chopper control function is provided for charging the storage battery for the facility to the electric vehicle or the like, a high degree of freedom can be obtained with respect to the voltage relationship between the storage battery for the facility and the storage battery for the electric vehicle or the like. To increase the versatility of the charging device. Further, in the present invention, the charging function can be secured while preventing overdischarging of the storage battery by limiting the output of the charger to the rated output of the AC / DC converter at the end of discharging of the storage battery.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention;

FIG. 2 is a circuit diagram of an embodiment,

FIG. 3 is a configuration diagram showing another embodiment of the present invention;

FIG. 4 is a circuit diagram of another embodiment,

FIG. 5 is a configuration diagram showing another embodiment of the present invention.

FIG. 6 is a circuit diagram of another embodiment.

FIG. 7 is a configuration diagram showing another embodiment of the present invention.

FIG. 8 is a circuit diagram of another embodiment.

FIG. 9 is a configuration diagram showing another embodiment of the present invention.

FIG. 10 is a circuit diagram of another embodiment.

FIG. 11 is a configuration diagram showing another embodiment of the present invention.

FIG. 12 is a charging waveform diagram of another embodiment.

FIG. 13 is a schematic diagram of a conventional charging device.

[Explanation of symbols]

2: electric vehicle, 4: storage battery, 21, 36, 46, 57
... Charging device, 24 ... Rectifier, 25,40,50,59 ...
Storage batteries for equipment, 26, 39, 49 ... chargers, 27, 4
1, 51: changeover switch, 27: control circuit, 32: chopper control circuit, 37, 47: reactor, 38, 48 ...
Power conversion circuits, 39, 49 charger, 58 AC / DC converter, 60 DC / DC converter.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-76139 (JP, A) JP-A-5-111171 (JP, A) JP-A 52-96230 (JP, U) JP-A 52-962 95022 (JP, U) Fully open 1987-25049 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02J ^7/ 00-7/12 H02J ⁷ /34-7/36 B60L 11/18

Claims (6)

(57) [Claims] A rectifier for rectifying an alternating current from a power receiving facility; a secondary battery for the facility; a charger for controlling low-current charging of the secondary battery and discharging from the secondary battery; The DC power from the rectifier is used as the DC input of the charger, and the DC output of the charger is switched to the charging input to the secondary battery. A charging control device for switching the DC power from the DC power to the DC input of the charger and switching the DC output from the charger to the charging input to the secondary battery. 2. An AC / DC step-up conversion control for an AC input and a DC / DC step-up control for an AC input by a facility secondary battery and a power conversion circuit having a bridge configuration of a reactor and a semiconductor switch at an input terminal. A charger that performs conversion control, and an AC current from a power receiving facility is always used as an AC input of the charger, and a DC output by the AC / DC boost conversion control of the charger is a charge input to the facility secondary battery. And when the charging from the load-side secondary battery is requested, the DC power of the secondary battery is used as the DC input of the charger, and the DC output of the charger is controlled by the DC / DC boost conversion control. A switching control circuit for performing switching control on charging input to the battery. 3. An AC / DC step-up conversion control for an AC input and a DC / DC step-up control for a DC input by a secondary battery for equipment and a power conversion circuit having a bridge configuration of a reactor and a semiconductor switch at an input terminal. A charger for performing conversion control, a switch circuit having a step-down chopper control function of a DC output of the facility secondary battery, and an AC current from a power receiving facility being always used as an AC input of the charger, and The DC output by the AC / DC step-up conversion control is switched to the charging input to the facility secondary battery, and the DC power of the secondary battery is chopper-controlled by the switch circuit when charging from the load-side secondary battery is requested. And a switching control circuit for switching the DC output from the DC / DC boost conversion control of the charger to the charging input to the secondary battery. And a charging device. 4. A cascade connection of a reactor and a power conversion circuit having a bridge configuration of a semiconductor switch, wherein a DC output is obtained on the power conversion circuit side by AC / DC step-up conversion control for AC input from the reactor side. A charger that obtains a DC output on the reactor side by DC / DC step-down conversion control with respect to a DC input from the power conversion circuit side, and a DC power supply connected to a DC input / output terminal of the power conversion circuit of the charger. A secondary battery for equipment that performs charging / discharging, and the AC current from the power receiving equipment is always input to the reactor side of the charger, and the charger is switched to AC / DC conversion control. A switching control circuit for switching the charger to DC / DC conversion control when charging is required, and for switching a DC output from the reactor to a charging input to the secondary battery. Charging device. 5. A cascade connection of a reactor and a power conversion circuit having a bridge configuration of a semiconductor switch, wherein a DC output is obtained on the power conversion circuit side by AC / DC step-up conversion control for AC input from the reactor side. A charger that obtains a DC output on the reactor side by DC / DC step-down conversion control with respect to a DC input from the power conversion circuit side, and a DC power supply connected to a DC input / output terminal of the power conversion circuit of the charger. A secondary battery for equipment that performs charging and discharging, a switch circuit having a boost chopper control function of a DC output from the reactor side of the charger, and an AC current from a power receiving facility is always input to the reactor side input of the charger. At the same time, switches the charger to AC / DC conversion control, switches the charger to DC / DC conversion control when charging is requested from the secondary battery on the load side, and switches the charger from the reactor. And a switching control circuit for taking out the DC output of the switch circuit under chopper control of the switch circuit and switching the input to the charging input to the secondary battery. 6. An AC / DC converter having a small current capacity for converting AC power from a power receiving facility into DC power, and a secondary battery floatingly charged with DC power from the AC / DC converter,
A DC / DC converter that obtains DC power from the secondary battery and the AC / DC converter and charges the load-side secondary battery with a large current, wherein the DC / DC converter is configured so that the A charging device provided with output limiting means for limiting the charging output to the rated output of the AC / DC converter when the condition is satisfied.