JP2002084673A - Power management system - Google Patents

Abstract

(57) [Problem] To provide a system capable of mutually transmitting electric power between an electric vehicle and a house, and to enable a grid-connected inverter to operate stably with high efficiency at the time of discharging. SOLUTION: In discharging, a DC voltage monitoring device 103 is used.
Acquires the DC input voltage of the system interconnection inverter 33 and outputs it to the charge / discharge controller 31 ′. The charge / discharge controller 31 ′ supplies the obtained DC input voltage to the battery controller 1 via the first and second communication antennas 35 and 51.
10 ′, the battery controller 110 ′ transmits the received DC input voltage to the inverter controller 113 ′.
Output to By switching between full-bridge operation and half-bridge operation of the on-board charge / discharge inverter 53 according to a command from the inverter controller 113 ′, the DC input voltage can be kept within a certain range, and the stable operation and discharge efficiency of the grid-connected inverter 33 can be achieved. Efficiency can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power management system for managing power efficiently, and more particularly to a power management system between a house and an electric vehicle.

[0002]

2. Description of the Related Art Conventionally, as a power management system using an electric vehicle, power is supplied from a home power supply in a house to a battery of the electric vehicle, and conversely, power is supplied from the electric vehicle to the house in an emergency or the like. The system is being developed. For example, the home power supply system disclosed in Japanese Patent Application Laid-Open No. H11-178234 includes a charger / discharger connected to the grid power on the house side, and a charge / discharge system provided on the electric vehicle side. It is possible to charge and discharge both with the house.

[0003] The residential side charger / discharger converts a household AC power into a high-frequency AC power when supplying (ie, charging) power from a household power supply in the house to a battery of the electric vehicle. Inverter and high frequency A when power is supplied (ie, discharged) from the electric vehicle to the house side
A second inverter for converting C power into household AC power, first and second selection switches for switching between the first inverter and the second inverter, and an output side (first side) of the first inverter. And a charging / discharging paddle which is a charging / discharging connector connected to the input side of the second inverter).

[0004] On the other hand, the electric vehicle has a charging / discharging connector inlet and a high frequency AC power for charging.
A third inverter for converting to electric power and a DC for discharging
A fourth inverter for converting power to high frequency AC power,
A third and a fourth selection switch for switching between the third inverter and the fourth inverter, and a battery connected to the output side of the third inverter (the input side of the fourth inverter). ing.

[0005]

The above-mentioned JP-A-11-1
In the household power supply system of No. 78234, the second inverter used when supplying electric power from the electric vehicle to the house needs to ensure the power quality of the home power supply. Once AC power is DC
It is common to rectify the power and convert the rectified DC power to household AC power.

At this time, the DC input voltage (DC input voltage) of the grid-connected inverter that converts DC power into household AC power at the house side is determined by the state of the house load, the battery voltage of the electric vehicle, and the fourth inverter. Is determined from the configuration. Here, the grid-connected inverter is D
There is a range where the power conversion efficiency is increased by the C input voltage (optimum operating voltage range) and a range where the power conversion efficiency is lowered. At least this DC input voltage falls within a range where the grid-connected inverter can operate (operating voltage range). is necessary.

When the fourth inverter is constituted by a full-bridge inverter, when the battery voltage is low and the load resistance on the house side is low (that is, the power consumption is high), the grid-connected inverter operates optimally at the DC input voltage. Stable operation within the voltage range. When the battery voltage is low and the load resistance on the house side is high (that is, the power consumption is low),
Although the DC input voltage falls within the operating voltage range, the power conversion efficiency decreases. When the battery voltage is high and the load resistance on the house side is low, the grid-connected inverter operates stably with the DC input voltage within the optimum operating voltage range. When the battery voltage is high and the load resistance on the house side is high, the DC input voltage is high and may exceed the operating range.

When the fourth inverter is constituted by a half-bridge inverter, when the battery voltage is low and the load resistance on the house side is low, the DC input voltage is low and may fall below the operating range. Battery voltage is low,
When the load resistance on the house side is large, the grid-connected inverter operates stably with the DC input voltage within the optimum operating voltage range.
When the battery voltage is high and the load resistance on the house side is low, the DC input voltage is low and may fall below the operating range. When the battery voltage is high and the load resistance on the house side is high, the grid-connected inverter operates stably with the DC input voltage within the optimum operating range.

Therefore, if the fourth inverter is fixed to either a full-bridge inverter or a half-bridge inverter, the grid-connected inverter will not operate stably depending on the combination of the battery voltage and the load resistance on the house side. There is a problem.

[0010] Therefore, the present invention provides a power source for operating a grid-connected inverter with high efficiency and stable operation and increasing discharge efficiency in a wide range of combinations of battery voltage and house-side load resistance during discharge. The purpose is to provide a management system.

[0011]

For this purpose, the invention according to claim 1 comprises a charger / discharger connected to a power line for supplying external grid power to a domestic load on the house side, and a main controller for performing overall control. A power management system capable of mutually transmitting power between a battery mounted on the electric vehicle and a house via the charger / discharger, wherein the electric vehicle includes a vehicle-mounted charge / discharge inverter; The inverter switches between full-bridge inverter operation and half-bridge inverter operation according to the battery voltage when the inverter supplies power from the electric vehicle to the house.

According to a second aspect of the present invention, the in-vehicle charge / discharge inverter switches between a full-bridge inverter operation and a half-bridge inverter operation according to the battery voltage and the state of the domestic load.

According to a third aspect of the present invention, there is provided a charging / discharging device connected to a power line for supplying external system power to a domestic load on a house side, and a main controller for performing overall control. In a power management system capable of mutually transmitting power between a battery mounted on an electric vehicle and a house, the electric vehicle includes a vehicle-mounted charge / discharge inverter, and the house-side charge / discharge device includes a high-frequency power inverter. And a grid-connected inverter that converts DC power rectified by the high-frequency power inverter to AC power for home use when the vehicle-mounted charge / discharge inverter supplies power from the electric vehicle to the house. Switching between full-bridge inverter operation and half-bridge inverter operation according to the DC input voltage of the inverter.

According to a fourth aspect of the present invention, there is provided a power management system including a high-frequency power inverter and a grid-connected inverter on a house side, wherein power can be transmitted from a battery mounted on an electric vehicle to the house side by electromagnetic induction.
An inverter provided between a coil of an electric vehicle used for electromagnetic induction and the battery, wherein a first diode and a third diode are connected in series, and both ends are connected to both ends of the battery. One diode group, a second diode and a fourth diode are connected in series,
A second diode group having both ends connected in parallel with the first diode group to both ends of the battery, a transistor connected in parallel with each diode, and an equal capacity capacitor connected in series between both ends of the battery. A capacitor,
A relay for switching and connecting a contact connected to one end of the coil to a contact connected between a second diode and a fourth diode and a contact connected between the capacitors; The other end is the first diode and the third
When power is supplied from the electric vehicle to the house side, one end of the coil is connected between a second diode and a fourth diode by switching the relay. A bridge state and a half bridge state in which one end of the coil is connected between capacitors are obtained.

[0015]

According to the first aspect of the present invention, when electric power is supplied from the electric vehicle to the house side, the full-bridge inverter operation of the on-board charge / discharge inverter mounted on the electric vehicle and the half-bridge inverter in accordance with the voltage of the battery. Since the operation is switched, the DC input voltage of the system interconnection inverter can be changed according to the change in the battery voltage, and the discharge efficiency can be increased.

According to the second aspect of the present invention, in addition to the effects of the first aspect, the full-bridge inverter operation and the half-bridge inverter operation of the vehicle-mounted charge / discharge inverter are switched according to the state of the domestic load together with the battery voltage. Therefore, it is possible to change the DC input voltage of the grid-connected inverter in response to the fluctuation of the domestic load, and it is possible to improve the discharge efficiency.

According to the third aspect of the present invention, when electric power is supplied from the electric vehicle to the house side, the full-bridge inverter operation of the on-board charge / discharge inverter mounted on the electric vehicle according to the DC input voltage of the grid-connected inverter. And the half-bridge inverter operation are switched, so that the DC input voltage of the grid-connected inverter can be kept within a certain range, and the stable operation of the grid-connected inverter and a higher discharge efficiency can be achieved.

According to the fourth aspect of the present invention, switching between full-bridge inverter operation and half-bridge inverter operation can be performed only by adding an equal-capacitance capacitor and one relay connected in series. When power is supplied to the power supply, the discharge efficiency can be increased with a simple structure.

[0019]

Embodiments of the present invention will be described below with reference to examples. FIG. 1 shows the configuration of a power management system to which the present invention is applied as a first embodiment. First, the house 20 will be described. On the house 20 side, various domestic loads 21 are connected to the system power from the power company via the switchboard 11. In the house, there is provided a main controller 100 for performing overall control of the system. The main controller 100 includes an interface 101, a load state monitoring device 102 for monitoring the usage state of the domestic load 21, and a charge / discharge device 3
0 is connected to the charge / discharge controller 31. The interface 101 has a function of displaying the state (ie, charge or discharge mode, time, remaining battery capacity, and the like) at the time of charge and discharge, and a function of receiving an input operation from a user.

The main controller 100 has a time management function, a voltage, an input / output current and a remaining capacity (hereinafter referred to as a battery state) of a battery of the electric vehicle 50 (to be described later), a running history, a reserve power amount, a reserve power amount, and a paddle connection signal. Are received from the charge / discharge controller 31. Then, it is determined whether to supply (charge) the electric vehicle 50 or supply (discharge) the electric power from the electric vehicle 50 to the house 20 based on the data and the time, and output the result to the charge / discharge controller 31. . In addition, the usage state of the home load 21 is received from the load state monitoring device 102, and the received usage state of the home load 21 is output to the charge / discharge controller 31. In addition, the battery state and the mode state of the charge or discharge mode are indicated by the interface 10.
Output to 1. The main controller 100 sends out corresponding output request signals to obtain the various information and signals described above.

A charge / discharge device 30 is further connected to the switchboard 11. The charge / discharge device 30 includes a converter 32 connected to the switchboard 11 and a charge / discharge controller 31 connected to the converter 32 and the main controller 100 described above.

The converter 32 is composed of a system interconnection inverter 33 connected to the switchboard 11 and a high frequency power inverter 34. A charge / discharge paddle 36 is connected to the high frequency power inverter 34 by a first communication antenna. 35
Are connected to the charge / discharge controller 31, respectively.
The charge / discharge controller 31 receives the battery state, the traveling history, the secured power amount, the remaining power amount, and the paddle connection signal from the electric vehicle 50 via the first communication antenna 35, and receives these data from the main controller 100. , A charge or discharge command from the main controller 100 and the state of the domestic load 21, and transmit a charge / discharge control signal and a load state to the first communication antenna 35.
, And a function of controlling charging and discharging of the converter 32.

The system interconnection inverter 33 includes a battery 60
It has a function of converting household AC power into DC power when charging the battery, and converting DC power into household AC power when discharging. The high-frequency power inverter 34 has a function of converting DC power into high-frequency AC power when charging, and converting high-frequency AC power into DC power when discharging. Therefore, converter 32 has a function of converting household AC power into high-frequency AC power when charging, and converting high-frequency AC power into household AC power when discharging.

The charging paddle 36 is connected to a high-frequency power inverter 34 in the converter 32, and has one coil 37 constituting a transformer so that power can be transmitted to an inlet 52 described later by electromagnetic induction. Have. The first communication antenna 35 connected to the charge / discharge controller 31 is connected to a second communication antenna 5 described later.
1 is provided with a function to perform wireless communication.

Next, the electric vehicle 50 will be described. A battery 60 is connected to the inlet 52 via a vehicle-mounted charge / discharge inverter 53. The inverter controller 113 is connected to the vehicle-mounted charge / discharge inverter 53. And, the inlet 52, the battery 60,
The battery controllers 110 are connected to the inverter controllers 113, respectively. Further, the battery controller 110 includes a second communication antenna 51.
Are connected, and the surplus power calculation device 111 and the traveling history acquisition device 112 are sequentially connected. A motor 62 is connected to the battery 60 via a motor inverter 61. The motor inverter 61 includes:
Motor controller 120, torque request generation device 121
Are sequentially connected, and the torque request generation device 121 is connected to the motor 62 and the input device 122.

The inlet 52 is provided with a charging / discharging paddle 36 and the other coil 55 constituting a transformer so that power can be transmitted by electromagnetic induction, and means for detecting connection of the charging / discharging paddle 36. It has a function of outputting a paddle connection signal to the battery controller 110.

The battery controller 110 monitors the battery status and transmits the battery status to the surplus power calculator 111. Then, a driving history and a surplus power calculation result, which will be described later, are received from the surplus power calculation device 111, and a connection signal of the charging paddle 36 is received from the inlet 52. The signal is transmitted to the charger / discharger 30 via the second communication antenna 51. Further, the charger / discharger 30
A charge / discharge control signal, which will be described later, and the load state of the house are received from the side via the second communication antenna 51, and the charge / discharge control signal, the load state of the house, and the battery state are output to the inverter controller 113.

The running history acquisition device 112 is a
As the traveling history of 0, the traveling distance per trip from when the charging paddle 36 is disconnected to when it is connected, the date and time, and the battery state transmitted from the battery controller 110 via the surplus power calculation device 111 are recorded. And outputs the recorded travel history to the surplus power calculation device 111.

The surplus power calculation device 111 receives the battery status and the paddle connection signal from the battery controller 110 and transmits the battery status and the paddle connection signal to the traveling history acquisition device 112. Then, the traveling history acquisition device 112
, The power consumption per trip is learned as the amount of power required for the user to travel back and forth to the daily life zone, and stored as the secured power amount. Further, the amount of power obtained by excluding the emergency power amount (for example, 20% of the total battery capacity) and the secured power amount from the remaining capacity of the battery 60 is calculated as the surplus power amount, and the travel history, the secured power amount, and the surplus power amount are calculated. Is output to the charger / discharger 30 via the battery controller 110 and the second communication antenna 51.

The traveling motor 62 is a three-phase AC motor, and is driven by the three-phase AC power converted from the DC power of the battery 60 by the motor inverter 61. The torque request generation device 121 receives a signal from the input device 122 for detecting the operation amount of the accelerator pedal, detects the current state of the motor 62, creates a required torque request signal, and Output to 120. The motor controller 120 receives a signal from the torque request generation device 121 and outputs a control signal to the motor inverter 61. Motor inverter 61
Is a three-phase AC inverter 61, which operates according to a control signal from the motor controller to drive the motor 62.

The in-vehicle charge / discharge inverter 53 converts high-frequency AC power into DC power when charging the battery 60 and converts DC power into high-frequency AC power when discharging from the battery 60 according to a control signal from an inverter controller 113 described later. It has a function of converting to electric power, and a function of switching between full-bridge operation and half-bridge operation in inverter operation when discharging.

Next, the flow of the charging and discharging mode switching control operation in the main controller 100 is shown in the flowcharts of FIGS. First, step 10
At 1, it is checked whether the charging paddle 36 is connected to the inlet 52. This is detected based on the presence / absence of a paddle connection signal transmitted from the battery controller 110 of the electric vehicle 50 to the charger / discharger 30 via the first and second communication antennas 35 and 51 to be described later.
This step is repeated until it is detected that the charging paddle 36 is connected to the inlet 52.

When the charging paddle 36 is connected to the inlet 52, it is next checked in step 102 whether or not the current time belongs to a late-night power time zone in which system power is low-cost late-night power. If not during midnight power hours,
In step 103, a battery status and an output request signal of a surplus power calculation result described later are transmitted to the electric vehicle 50 side, and data from a surplus power calculation device 111 described later via the battery controller 110 is received. It is checked whether or not the battery 60 has remaining power.

When there is remaining power, the process proceeds to step 104 to start discharging (supply of power from the battery 60 to the house 20). That is, the charge / discharge controller 31 receiving the discharge start command from the main controller 100 outputs the discharge start signal to the battery controller 110.
And the discharging operation of the converter 32 is performed. On the electric vehicle 50 side, the battery controller 11
0 causes the in-vehicle charge / discharge inverter 53 to perform a discharging operation.

During the discharge, in step 105, the remaining power calculating device 111 is set at predetermined time intervals, for example, 1 second.
, And monitors whether or not the battery 60 has a surplus power amount. Then, while there is remaining power, at step 106, it is checked whether the current time is in the midnight power time zone. Here, if it is not the midnight power time zone, the discharge is continued and the process returns to step 105.

If there is no remaining power in the check in step 105, or if the current time enters the midnight power time zone in the check in step 106, step 1
Proceed to 07. In step 107, whether or not the system power is normal is checked based on whether or not a system abnormality signal has been received from the converter 32. If the system power is not normal, that is, if there is a power outage, the process proceeds to step 108 and continues to discharge, and the check in step 107 is repeated until the system power becomes normal.

If it is determined in step 107 that the system power is normal, the discharge is terminated in step 109. That is, the charge / discharge controller 31 that has received the discharge end command ends the discharge operation of the converter 32 and transmits a discharge end signal to the battery controller 110. On the electric vehicle 50 side, the battery controller 110 terminates the discharging operation of the vehicle-mounted charge / discharge inverter 53.

Thereafter, in step 111, it is checked whether or not the current time is in the midnight power time zone, and the check is repeated until the current time is in the midnight power time zone. Then, when the midnight power time zone is reached, the process proceeds to step 112, and charging of the battery 60 is started. That is, the charge / discharge controller 31 that has received the charge start command from the main controller 100 transmits a charge start signal to the battery controller 110 of the electric vehicle, and causes the converter 32 to perform a charge operation. On the electric vehicle 50 side, the battery controller 110 causes the in-vehicle charge / discharge inverter 53 to perform a charging operation. Thereafter, while receiving and checking the battery status monitored by the battery controller 110, charging is continued until the battery is fully charged.

On the other hand, if there is no surplus power in the check in step 103, the flow advances to step 113 to check whether or not the system power is normal. Here, when the system power is normal, at step 110, data from the surplus power calculation device 111 is received, and it is checked whether or not there is a reserve power amount. If there is no sufficient power, there is a risk that going out may be hindered.
Proceed to 2 to start charging the battery 60.

If there is a reserve power amount in the check in step 110, it is possible to cope with going out of one trip.
After proceeding to step 111 and detecting that the midnight power time zone has come, charging of the battery 60 is started in step 112.

If the result of the check in step 113 is a power failure, the process proceeds to step 115 to start discharging. During the discharging, it is checked at step 116 whether or not the system power is normal at predetermined time intervals. During the power failure, the discharging is continued at step 117 until the system power 10 becomes normal. repeat.

Thus, the power supply from the electric vehicle 50 to the home load 21 of the house 20 is continued until the system power 10 becomes normal. If it is detected in step 116 that the system power 10 has returned to normal, the discharging is terminated in step 118 and
Proceed to 2 to start charging.

If the current time is in the midnight power time zone in the check in step 102, it is checked in step 114 whether the system power 1 is normal. If the system power 10 is normal, the process proceeds to step 112,
Start charging. On the other hand, if the result of the check in step 114 is a power failure, the process proceeds to step 115 to start discharging. Thereafter, steps 113 to 115
In the same manner as when the process has proceeded, the discharge is continued until the system power 10 becomes normal, power is supplied to the home load 21 of the house 20, and then charging is started.

As described above, the switching between the charging mode and the discharging mode is performed when the user operates the charging paddle 36 through the inlet 52.
It is done automatically just by connecting to. In addition,
In this embodiment, it is also possible to forcibly switch between the charge mode and the discharge mode by prioritizing the automatic switching operation shown in the above-mentioned flowchart by the user's input operation on the interface 22.

As described above, by controlling charging or discharging in accordance with the secured power amount and the remaining power amount of the battery 60, the time zone, and the state of the system power 10, it is possible to charge at low cost with late-night power and to perform a power outage or the like. Grid power 1
If there is an abnormality in the home load 21 from the battery 60,
Can be powered. And system power 10
As long as there is no abnormality in the battery, the user reserves the required amount of power necessary for traveling to and from the predetermined place in the daily life and the emergency power amount in the battery 60. The electric energy can be used on the house 20 side.

Next, FIG. 4 shows a circuit configuration of the on-vehicle charge / discharge inverter 53. Diodes D1, D2, D3, D are provided between the inlet 52 and the battery 60 so as to be able to operate as a full bridge rectifier during charging.
4 are formed, each of which has a
Points A and B, which are input / output terminals of the inlet 52, are connected between the diodes D1 and D3 and between D2 and D4, and both ends of the battery 60 are connected between the diodes D1 and D2 and between D3 and D4. . Capacitor C1 is connected to relay Ry at points A and B at the input / output end of inlet 52.
1 and capacitors C2 and C3 having the same capacity are connected in series between both ends of the battery 60.

The diodes D1, D2, D3 and D4 have:
Transistors Tr1, Tr2, Tr3, Tr4 respectively
Are arranged in parallel. Further, a relay Ry2 is provided, and a contact a connected to the point B is connected to a diode D
The connection is switched to a c-contact connected between D2 and D4 or a b-contact connected to a point Mb between the capacitors C2 and C3. Each relay R
y1, Ry2 and transistors Tr1, Tr2, T
The switches r3 and Tr4 are connected to the inverter control circuit 54, and are switched or turned on / off by a signal from the inverter control circuit 54 that receives a command from the inverter controller 113.

At the time of charging, both ends of the capacitor C1 provided in the high-frequency AC input stage are connected to the input terminals A and B by the first relay Ry1, respectively. The contact and the c contact are connected. The transistors Tr1, Tr2, Tr3, Tr4 are all off. Thereby, the on-vehicle charge / discharge inverter 53 operates as a full-bridge rectifier composed of diodes D1, D2, D3, and D4, converts high-frequency AC power input from the inlet 52 side to DC power, and outputs the DC power to the battery 60 side. I do. Note that the capacitors C2 and C3 are smoothing capacitors.

At this time, the current flows from the negative side of the battery 60 through the diode D4 to the point B at the input terminal, and from the point A at the input terminal through the diode D1 as shown by the solid arrow in FIG. The state in which the battery flows to the plus side of the battery 60 and the state in which the battery flows from the minus side of the battery 60 through the diode D3 to the point A at the input terminal, and from the point B at the input terminal through the diode D2 as indicated by the broken arrow in FIG. The state of flowing to the positive side of 60 is alternately repeated.

When discharging, the DC power input from the battery 60 is converted into high-frequency AC power and output to the inlet 52, so that the transistors Tr1, Tr2,
Either the operation as a full-bridge inverter composed of Tr3 and Tr4 or the operation as a half-bridge inverter composed of transistors Tr1 and Tr3 is selected. Further, when the first relay Ry1 is opened, the capacitor C1 is disconnected from the output terminals A and B, and does not hinder the output of the high-frequency AC power.

Transistors Tr1, Tr2, Tr3, T
When operating as a full-bridge inverter composed of r4, the second relay Ry2 connects the a contact to the c contact. Each transistor is an inverter control circuit 5
The on / off operation is performed by the switching signal from the control unit 4. When the transistors Tr1 and Tr4 are turned on and the transistors Tr2 and Tr3 are turned off, the potential at the output end point A becomes the plus potential of the battery 60, and at the output end point B becomes the minus potential of the battery 60. Flows from the side to the point B side. Conversely, when the transistors Tr1 and Tr4 are turned off and the transistors Tr2 and Tr3 are turned on, the potential at the output end point A becomes the negative potential of the battery 60, and at the output end point B becomes the positive potential of the battery 60. It flows from point B to point A. This is alternately repeated at a high frequency cycle to output high frequency AC power.

At this time, the current flows from the plus side of the battery 60 to the output terminal A through the transistor Tr1 and from the output terminal B to the transistor Tr4 as shown by the solid arrow in FIG. The state where the battery 60 flows to the minus side of the battery 60 and the state where the battery 60 flows from the plus side of the battery 60 to the point B through the transistor Tr2, and from the point A to the point B through the transistor Tr3 as shown by a broken arrow in FIG.
The state of flowing to the minus side of 0 is alternately repeated.

When operating as a half-bridge inverter composed of transistors Tr1 and Tr3, the second
Relay Ry2 connects the a contact to the b contact. Since the b-contact is connected to the point Mb between the capacitors C2 and C3 having the same capacitance, the intermediate potential of the battery 60 is given at the point B at the output end. Transistor Tr1,
Tr3 performs an on / off operation in response to a switching signal from the inverter control circuit 54, and the transistor Tr3
2. Tr4 remains off. When the transistor Tr1 is turned on and the transistor Tr3 is turned off, the output terminal A has a positive potential of the battery 60 at point A, and current flows from point A to point B. Conversely, when the transistor Tr1 is turned off and the transistor Tr3 is turned on, the potential of the output terminal A becomes the negative potential of the battery 60, and the current flows from the point B to the point A. This is alternately repeated at a high frequency cycle to output high frequency AC power.

At this time, the current flows from the plus side of the battery 60 through the transistor Tr1 to the point A, and from the point B to one end of the capacitor C3 through the point Mb, as indicated by the solid arrow in FIG. With capacitor C3
And the state in which the battery 60 flows from the opposite side to the negative side of the battery 60, as shown by the broken arrow in FIG.
Flows from the plus side to one end of the capacitor C2, and across the capacitor C2, from the opposite side through the point Mb.
The state of flowing to the point and flowing from the point A to the minus side of the battery 60 through the transistor Tr3 is alternately repeated.

As described above, when operating as a full-bridge inverter, the high-frequency AC power output terminal A
The voltage between the terminals at points B and B becomes the battery voltage, and when operating as a half-bridge inverter, the potential at point B is the intermediate potential of the battery 60. The intermediate voltage is half of the battery voltage.

The inverter controller 113 receives a charge / discharge control signal, a house load state signal and a battery state signal from the battery controller 110, instructs the on-board charge / discharge inverter 53 to perform a charging operation or a discharging operation, and discharges the battery. At this time, it is determined whether the in-vehicle charge / discharge inverter 53 operates as a full-bridge inverter or a half-bridge inverter based on the load state of the house and the voltage of the battery 60.
Command 3

Next, a method of determining whether to operate as a full-bridge inverter or a half-bridge inverter will be described with reference to FIG. In FIG. 8, the vertical axis represents the DC input voltage (DC input voltage) of the grid interconnection inverter 33 at the time of discharging, and the horizontal axis represents the load state of the house. Low power consumption). When the battery voltage Eb when operating as a full-bridge inverter is large (thick line) and small (thin line), and when the battery voltage Eb when operating as a half-bridge inverter is large (thick line) and small ( 3) Grid-connected inverter 3
3 shows the characteristics of the DC input voltage, and shows the operating voltage range and the optimum operating voltage range of the grid interconnection inverter 33.

The inverter controller 113 stores the table of FIG. 8 as a reference table, and controls the battery voltage Eb and the load condition of the house so that the DC input voltage of the grid-connected inverter falls within the optimum operating voltage range. It is determined whether the in-vehicle charge / discharge inverter is to be operated in full bridge operation or half bridge operation.

When the battery voltage Eb is high and the power consumption is small, the operating range of the grid-connected inverter is exceeded in the full-bridge operation, and the optimum operating voltage range of the grid-connected inverter in the half-bridge operation. Therefore, the half-bridge operation is performed. Battery voltage E
When b is large and the power consumption is large, the characteristic becomes lower than the operating voltage range of the grid-connected inverter in half-bridge operation, and conversely, the operating voltage range of the grid-connected inverter in full-bridge operation. , A full bridge operation is performed.

When the battery voltage Eb is low and the power consumption is low, the full-bridge operation is within the operating voltage range of the grid-connected inverter, but is higher than the optimum operating voltage range. In this case, the half-bridge operation is performed because the characteristics show the characteristics within the optimal operating voltage range of the grid-connected inverter. And the battery voltage Eb
When the power consumption is large when the power consumption is small, the operating voltage is lower than the operating voltage range of the grid-connected inverter in half-bridge operation, and conversely, it is the operating voltage range of the grid-connected inverter in full-bridge operation. Therefore, a full bridge operation is performed.

With the above configuration, when discharging, the inverter operation of the vehicle-mounted charging / discharging inverter 53 is switched between full-bridge operation and half-bridge operation in accordance with the voltage of the battery 60 and the state of the domestic load 21. The DC input voltage of the grid interconnection inverter 33 can be kept within a certain range, and a wide range with respect to the voltage of the battery 60 and an increase in discharge efficiency can be achieved.

In the first embodiment, the inverter controller 113 of the electric vehicle 50 has the function of determining whether the on-board charging / discharging inverter 53 switches between the full-bridge inverter operation and the half-bridge inverter operation. The discharge controller 31 may be provided. At this time, the charge / discharge controller 31 includes a lookup table as shown in FIG. 8, and the voltage value Eb of the battery 60 of the electric vehicle 50 is
10 and obtained through the second communication antenna 51 and the first communication antenna 35 to determine whether to switch the full-bridge inverter operation and the half-bridge inverter operation.
The determination result is transmitted to the inverter controller 113 via the first communication antenna 35, the second communication antenna 51, and the battery controller 110, and the inverter controller 113 determines the inverter of the on-vehicle charge / discharge inverter 53 from the received determination result. The full-bridge inverter operation or the half-blip inverter operation is instructed to the control circuit 54.

Next, a second embodiment will be described. FIG.
FIG. 1 is a diagram illustrating a configuration of a power management system according to an embodiment. The difference from the first embodiment is that the charge / discharge device 3 is replaced with the load condition monitoring device 102 provided on the house side.
0 ′, DC voltage monitoring device 1 that monitors the voltage between grid-connected inverter 33 and high-frequency power inverter 34
03 is connected to the charge / discharge controller 31 ′.

The DC voltage monitor 103 is connected to the electric vehicle 5
When power is supplied from 0 ′ to the house 20 ′, the DC input voltage of the grid interconnection inverter 33 is detected and output to the charge / discharge controller 31 ′. And charge / discharge controller 3
1 ′ transmits the obtained DC input voltage to the battery controller 110 ′ via the first communication antenna 35 and the second communication antenna 51. Battery controller 1
10 ′ outputs the received DC input voltage to the inverter controller 113 ′. Inverter controller 11
3 'stores data on the operating voltage range and the optimal operating voltage range of the grid interconnection inverter 33.

Next, FIG. 10 is a flowchart showing a flow of switching the inverter operation between the full bridge and the half bridge of the vehicle-mounted charging / discharging inverter 53 in the inverter controller 113 'at the time of discharging. Step 201
Then, a discharge start command is received from the main controller 100 ′ via the charge / discharge controller 31 ′, the first communication antenna 35, the second communication antenna 51, and the battery controller 110 ′.
To start discharging in the half-bridge inverter operation.

In step 202, the DC interconnection monitor 33 in the charger / discharger 30 'is operated by the DC voltage monitor 103.
, And the charge / discharge controller 31 ′,
The signal is received via the first communication antenna, the second communication antenna 51, and the battery controller 110 '. In addition,
In the following, the transmission / reception paths for commands and data are the same. In step 203, the main controller 10
It is checked whether a discharge stop command has been received from 0 '. Then, when the discharge stop command is received, step 21 is executed.
0, and if no discharge stop command has been received, the process proceeds to step 204.

In step 204, it is checked whether the detected DC input voltage has fallen below the optimum operating voltage range of the grid interconnection inverter 33. If the value is lower than the predetermined value, the process proceeds to step 205. If the value is not lower, the process proceeds to step 2.
Return to 02.

In step 205, an instruction is issued to the inverter control circuit 54 of the on-board charging / discharging inverter 53 to switch to the full-bridge inverter operation. In step 206,
Similarly to step 202, the DC input voltage of the grid interconnection inverter 33 is received and acquired by the DC voltage monitoring device 103.

In step 207, it is checked whether a discharge stop command has been received from the main controller 100 '. If a discharge stop command is received, step 2
The routine proceeds to step 10, and proceeds to step 208 if the discharge stop command has not been received.

In step 208, it is checked whether or not the detected DC input voltage has exceeded the optimum operating voltage range of the grid interconnection inverter 33. If it exceeds, the process proceeds to step 209. If it does not, the process proceeds to step 2
Return to 06.

At step 209, the inverter control circuit 54 of the in-vehicle charge / discharge inverter 53 is instructed to switch to the full-bridge inverter operation, and the process returns to step 202. In step 210, the discharge ends. Other configurations are the same as those of the first embodiment. The flow of the control operation for switching between the charging and discharging modes in the main controller 100 'is the same as that in the first embodiment.

With the above configuration, when electric power is supplied from the electric vehicle 50 ′ to the house 20 ′, the inverter operation of the vehicle-mounted charge / discharge inverter 53 is changed from the DC input voltage of the system interconnection inverter 33 to the full bridge operation or the half bridge operation. By switching to the operation, the DC input voltage can be kept within a certain range, and the stable operation of the system interconnection inverter 33, the wide range for the voltage of the battery 60, the response to the load fluctuation, and the improvement of the discharge efficiency can be achieved. Can be planned.

In the second embodiment, the inverter controller 113 'of the electric vehicle 50' has the function of determining whether the in-vehicle charge / discharge inverter 53 switches between the full-bridge inverter operation and the half-bridge inverter operation.
It may be provided in the charge / discharge controller 31 ′ of the charge / discharge device 30 ′. In this case, the input DC of the grid interconnection inverter 33 is
The charge / discharge controller 31 'includes data of the power operating voltage range and the optimum operating voltage range, and performs switching determination between the full-bridge inverter operation and the half-bridge inverter operation. The determination result is transmitted to the inverter controller 113 'via the first communication antenna 35, the second communication antenna 51, and the battery controller 110', and the inverter controller 113 '
A full-bridge inverter operation or a half-bridge inverter operation is instructed to the control circuit 54 of the vehicle-mounted charge / discharge inverter 53.

In each of the above embodiments, the communication antenna is used as the communication means between the house and the electric vehicle. However, the present invention is not limited to this. May be used.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating a flow of a control operation in the embodiment.

FIG. 3 is a flowchart illustrating a flow of a control operation in the embodiment.

FIG. 4 is a diagram schematically illustrating a circuit configuration of a vehicle-mounted charge / discharge inverter.

FIG. 5 is a diagram illustrating a current flow of the inverter circuit during charging.

FIG. 6 is a diagram illustrating the flow of current in a full-bridge inverter circuit during discharging.

FIG. 7 is a diagram illustrating the flow of current in the half-bridge inverter circuit during discharging.

FIG. 8 is a diagram showing the relationship between the DC input voltage of the grid-connected inverter and the load and battery voltage on the house side.

FIG. 9 is a block diagram showing the configuration of the second embodiment.

FIG. 10 is a flowchart showing a flow of switching of the inverter operation.

[Explanation of symbols]

 Reference Signs List 10 system power 11 switchboard 20, 20 'house 21 house load 30, 30' charge / discharger 31, 31 'charge / discharge controller 32 converter 33 system interconnection inverter 34 high frequency power inverter 35 first communication antenna 36 charging paddle 37, 55 Coil 50, 50 'Electric vehicle 51 Second communication antenna 52 Inlet 53 In-vehicle charge / discharge inverter 54 Inverter control circuit 60 Battery 61 Motor inverter 62 Motor 100, 100' Main controller 101 Interface 102 Load state monitoring device 103 DC voltage monitoring device 110, 110 'Battery controller 111 Remaining power calculation device 112 Running history acquisition device 113, 113' Inverter controller 120 Motor controller 121 Torque request generation Device 122 input device

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5G003 AA01 BA01 DA05 DA15 FA06 GB06 GB08 5G066 HB09 JA05 JB03 5H115 PA11 PG04 PI16 PO01 PO07 PO09 PO16 PU08 PV07 PV09 PV23 QN12 SL01 TI02 TI05 TI06 TI08 TO21 TR19

Claims (4)

[Claims] An electric vehicle is mounted on an electric vehicle via a charge / discharge device connected to a power line for supplying external system power to a domestic load and a main controller for performing overall control. In a power management system that enables power transmission between the battery and the house,
The electric vehicle includes a vehicle-mounted charge / discharge inverter, and the vehicle-mounted charge / discharge inverter switches between a full-bridge inverter operation and a half-bridge inverter operation according to the voltage of the battery when supplying power from the electric vehicle to the house. And a power management system. 2. The power supply according to claim 1, wherein the on-vehicle charge / discharge inverter switches between a full-bridge inverter operation and a half-bridge inverter operation according to the voltage of the battery and the state of the domestic load. Management system. And a main controller for performing overall control, wherein the main unit is provided with a charge / discharge device connected to a power line for supplying external system power to a home load, and is mounted on an electric vehicle via the charge / discharge device. In a power management system that enables power transmission between the battery and the house,
The electric vehicle includes an in-vehicle charge / discharge inverter.The house-side charge / discharge device includes a high-frequency power inverter and a system interconnection inverter.When the on-board charge / discharge inverter supplies power from the electric vehicle to the house, A power management system that switches between full-bridge inverter operation and half-bridge inverter operation according to the DC input voltage of a grid-connected inverter that converts DC power rectified by a high-frequency power inverter into AC power for home use. 4. An electric vehicle used for electromagnetic induction in a power management system including a high-frequency power inverter and a grid-connected inverter on a house side and capable of transmitting power from a battery mounted on the electric vehicle to the house side by electromagnetic induction. A first diode group having a first diode and a third diode connected in series, both ends of which are connected to both ends of the battery; and The second diode and the fourth
And a second diode connected in series to both ends of the battery in parallel with the first diode group.
A diode group, a transistor connected in parallel to each diode, a capacitor of equal capacitance connected in series between both ends of the battery, and a contact connected to one end of the coil connected to a second diode and a fourth diode. And a relay for switching between a contact connected between the diode and a contact connected between the capacitor and the other end of the coil connected between a first diode and a third diode. When power is supplied from the electric vehicle to the house, the relay is switched so that one end of the coil is connected between a second diode and a fourth diode in a full bridge state, and one end of the coil is connected. And a half-bridge state in which the capacitors are connected between capacitors.