KR20180017485A - Two-way charging system - Google Patents

Abstract

The present invention relates to a system capable of bidirectionally charging between an electric vehicle and an energy supply unit, and a method thereof. Specifically, the present invention is to more effectively utilize electric energy stored in an electric vehicle by charging any one of either a battery unit in the electric vehicle or an energy supply unit if necessary, and furthermore to have means capable of monitoring an electric energy supply state in bidirectional charging and means for preventing damages due to overcurrent/overvoltage.

Description

Two-way charging system [0002]

The present invention relates to a system capable of charging in both directions between an electric vehicle and an energy supply unit, and a method thereof. More specifically, the present invention aims at making it possible to use electric energy accumulated in an electric vehicle more efficiently by making it possible to charge the battery part and the energy supplying part of the electric vehicle to either one of them, Means for monitoring the electric energy supply state, and means for preventing damage due to overcurrent / overvoltage.

In recent years, demand for electric vehicles has increased significantly, and in response to social demands, the company is making efforts to build infrastructure to supply enough energy for electric vehicles.

On the other hand, electrical energy is generated by power plants from energy sources such as thermal power, hydroelectric power, and nuclear power, and the amount of resources is limited. Also, the power generation capacity for producing electric energy is also limited. Much effort is being made to manage.

In the future, if electric vehicles are commercialized more and the demand for electric vehicles steadily increases, the consumption of electric energy is expected to increase greatly. If such a situation arises, a sharp increase in the cost required to use electric energy Are expected to be inevitable, and supply and demand imbalances, which can not satisfy many demand, are also expected.

Therefore, in order to supply electric energy stably to cope with such a situation, a means of predicting the overall power demand and controlling the power supply is needed.

The present invention has been made in order to solve such a problem, and it has been invented to provide additional technical elements that can not easily be invented by a person having ordinary skill in the art, as well as satisfying the technical requirements in the foregoing.

The present invention relates to an energy supply of an electric vehicle, and it is intended to enable charging of a battery portion and an energy supply portion of an electric vehicle, but charging in both directions.

By realizing a bi-directional chargeable system, electric vehicles are charged normally and electric energy is supplied to the energy supply part in reverse direction when necessary, so that electricity can be reused and electric energy can be used in other demanding places.

Another object of the present invention is to prevent damage caused by an overcurrent or an overvoltage in bidirectional charging so as to improve the stability of the system.

According to an aspect of the present invention, there is provided a bi-directional charging system including an energy supply unit for supplying electric energy to a battery unit or supplying electric energy to the battery unit according to a charging mode, A sensing unit for sensing the magnitude of the current or voltage of the bus bar, and a controller for controlling the energy supply unit and the sensing unit.

Further, in the bi-directional charging system according to an embodiment of the present invention, the bus bar may include a positive bus bar and a negative bus bar.

The bidirectional charging system according to an embodiment of the present invention may further include a switch connected to both ends of the line of the positive bus bar or the negative bus bar and driven in an opened or closed state according to a control command of the controller .

In addition, the bidirectional charging system according to an embodiment of the present invention may further include an arc prevention device that disconnects the switch and the bus bar when the switch senses an overcurrent or an overvoltage.

In addition, the bidirectional charging system according to an embodiment of the present invention may include a current sensing unit, and the current sensing unit may sense a current magnitude of the positive bus bar or the negative bus bar.

In addition, the bidirectional charging system according to an embodiment of the present invention may include a voltage sensing unit, and the voltage sensing unit may sense a voltage difference between the positive bus bar and the negative bus bar.

Here, the bidirectional charging system according to an embodiment of the present invention is characterized in that the switch includes a first switch connected on the line of the positive bus bar and a second switch connected on the line of the negative bus bar, The voltage sensing unit may include a first voltage sensing unit sensing a voltage difference of a bus bar extending from one end of the first switch and a second switch, and a second voltage sensing unit sensing a voltage of a bus bar extending from the other end of the first switch and the second switch, And a second voltage sensing unit for sensing the vehicle.

The bidirectional charging system according to an embodiment of the present invention may further include a DC filter connected to one end of the energy supply unit and removing an AC component of electric energy supplied from the energy supply unit to the battery unit.

According to another aspect of the present invention, there is provided a bi-directional charging method comprising the steps of: (a) supplying an electric energy to a battery unit or supplying electric energy from the battery unit according to a charging mode; ) Sensing the magnitude of a current or voltage on the bus bar to which the electrical energy is transmitted, (c) if the magnitude of the current or voltage sensed in step (b) To the open state.

According to the present invention, the energy stored in the electric vehicle battery unit can be transmitted to the supply end as needed, thereby balancing the overall energy supply and demand.

In addition, according to the present invention, electric vehicles can be charged using electric energy supplied at a relatively low price in a predetermined time zone, for example, in the middle of the night, and electric energy set at a relatively high price during the day can be re- The energy can be economically consumed.

In addition, according to the present invention, it is possible to prevent damages due to an overcurrent or an overvoltage at the time of supplying electric energy, thereby enhancing the stability of the entire system.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a block diagram schematically showing the entire configuration of a bidirectional charging system according to the present invention.
FIG. 2 is an enlarged view of the area A of FIG. 1, that is, the control unit and the sensing unit.
Figure 3 shows a further embodiment of a switch in a bi-directional charging system.

DETAILED DESCRIPTION OF THE EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

The embodiments disclosed herein should not be construed or interpreted as limiting the scope of the present invention. It will be apparent to those of ordinary skill in the art that the description including the embodiments of the present specification has various applications. Accordingly, any embodiment described in the Detailed Description of the Invention is illustrative for a better understanding of the invention and is not intended to limit the scope of the invention to embodiments.

The functional terms shown in the drawings and described below are examples of possible expressions. In other embodiments, other terms may be used without departing from the spirit and scope of the following detailed description.

Furthermore, the expression "including an element" is merely referred to as an "open" expression, and the element should not be understood as excluding the additional elements.

Further, when an element is referred to as being "connected" or "in contact" with another element, it may be directly connected or in contact with the other element, but it should be understood that other elements may be present in between do.

Also, although the terms first, second, etc. may be used to describe various elements, the elements are not to be limited by the terms, and the terms may be used to distinguish one element from another Only.

1 shows a schematic configuration of a bidirectional charging system according to the present invention.

Referring to FIG. 1, a bidirectional charging system includes an energy supply unit 100, bus bars 310 and 330, a sensing unit 400, and a control unit 500 as a basic configuration.

The bidirectional charging system can be implemented as a bi-directional charging device, preferably in a state where the above configurations are included in one housing, and can be implemented in the form of, for example, an electric charging station. In addition, the bidirectional charging system according to the present invention is preferably assumed to be connected to and driven by the battery unit 200 in an electric vehicle in a state where the electric vehicle is connected. However, It should be understood that the present invention can also be applied to various kinds of devices and devices that can be driven by energy.

Hereinafter, each configuration will be described with reference to FIG.

First, the energy supplying unit 100 supplies electric energy to the battery unit 200 mounted in the electric vehicle or receives reverse electric energy from the battery unit 200 according to the charging mode.

The charging mode can be divided into a forward charging mode and a reverse charging mode. The forward charging mode is a state in which the energy is supplied from the energy supplying unit 100 to the battery unit 200, And the electric energy is supplied to the supplying unit 100. The switching of the charging mode can be controlled by the control unit 500, which will be described later, or can also be performed by control in the electric vehicle. For example, a person who wishes to use the bi-directional charging system can set the charging mode through a user interface (not shown) provided in the system while the electric vehicle is connected to the bidirectional charging system. Alternatively, The user may operate the interface of the electric vehicle to set the charging mode.

The energy supply unit 100 may be understood as any kind of energy storage means capable of supplying electric energy to the battery unit 200 of an electric vehicle such as an EVSE (Electric Vehicle Supply Equipment), an ESS (Energy Storage System)

As will be described later, the energy supply unit 100 may be connected to the control unit 500 via a network capable of data communication, and may be driven according to a control command received from the control unit 500. [

1, a DC filter may be connected to one end of the energy supply unit 100 or the bus bars 310 and 330 connected to the energy supply unit 100. As shown in FIG. The DC filter removes the AC component of the electric energy supplied from the energy supplying unit 100 to the battery unit 200. The DC filter may be included in the fast charging interface, but may be omitted in the slow charging interface. Therefore, in the fast charging, AC power can be applied to the battery unit 200.

Meanwhile, the battery unit 200 referred to in the description of the present invention refers to an electric energy storage provided in the electric vehicle. In this case, the battery unit 200 may include a rapid charging unit and a slow charging unit. In this case, the rapid charging unit charges the battery with a voltage of 380 V of any size of three-phase AC, and the charging unit can charge the battery with a voltage of 220 V of a single phase AC.

The bus bars 310 and 330 connect the energy supply unit 100 and the battery unit 200 and transfer electrical energy between the energy supply unit 100 and the battery unit 200. It is understood to include rod-shaped conductors that generally allow electrical connections in tanks, vehicles, aircraft, and the like. 1, the bus bar may be divided into a positive bus bar 310 and a negative bus bar 330. In the case of an AC bus, the bus bar may be divided into a positive bus bar 310 and a negative bus bar 330 And 330 of the anode bus bar 330 and the cathode bus bar 330 are conceptually distinguished for completeness of the circuit. When measuring the voltage magnitude between the energy supplying part 100 and the battery part 200, The voltage difference is measured.

Next, the sensing unit 400 senses the magnitude of the current or voltage of the bus bar. More specifically, the sensing unit 400 may include a current sensing unit 410 or a voltage sensing unit 420. The current sensing unit 410 may sense the magnitude of the current flowing through the bus bar to the voltage sensing unit 420, Detects the magnitude of the voltage across the bus bar.

In this case, for the understanding of the present invention, the sensing unit is shown in two configurations, and one sensing unit may sense at least one of the voltage and the current. In addition, one sensing section is a voltage / current sensing configuration, and the voltage sensing sections 420 and 430 may be configured separately.

The sensing unit 400 may be connected to the controller 500 to transmit and receive data. Accordingly, the magnitude of the current or voltage measured by the sensing unit may be transmitted to the controller 500 have.

The sensing unit will be described in more detail with reference to FIG.

FIG. 2 is an enlarged view of a region A of FIG. 1, and includes a current sensing unit 410 and a voltage sensing unit 420 in a detailed configuration of the sensing unit, It can be confirmed that the connection 110 is made so that the connection can be made.

First, referring to the current sensing unit 410, the current sensing unit 410 may be provided on any one of the anode bus bar and the cathode bus bar. In this case, as shown in FIG. 2, The cathode bus bar or the cathode bus bar of the bus bar is extended to both ends of the bus bar.

As a further embodiment, the current sensing part 410 may be of a Hall sensing type, in which a hall effect is generated when a magnetic field is applied to a conductor through which a current flows and a voltage is generated in a direction perpendicular to the current and the magnetic field And the direction and magnitude of the magnetic field are detected. Since the voltage generated at this time is proportional to the intensity of the current and the magnetic field, it is also used to measure the magnitude of the current flowing through the conductor.

As a further embodiment, the voltage sensing unit 420 may measure the potential difference between the anode bus bar 310 and the cathode bus bar 330. The voltage sensing unit 420 may include a large value internal resistance . In one embodiment, it may have a larger value than all resistors in the circuit connected in the bi-directional charging system.

The voltage sensing units 420 and 430 may be disposed at one end near the energy supply unit 100 and at one end near the battery unit 200 on the basis of the center point of the bus bar and may be a forward charging mode or a reverse charging mode This is to easily detect the occurrence of overvoltage at a certain time.

Referring back to FIG. 1, the control unit 500 will be described.

The control unit 500 controls the energy supply unit 100 and the sensing unit described above. The control unit 500 may include at least one computing means and storage means, which may be a general purpose central processing unit (CPU), but may be implemented as a programmable device device (CPLD, FPGA ) Or an application specific integrated circuit (ASIC) or microcontroller chip. Also, the storage means may be a volatile memory element, a non-volatile memory or a non-volatile electromagnetic storage element, or a memory within the computing means.

The control unit 500 may be connected to the energy supply unit 100 or the wired or wireless network 110 capable of data communication with the sensing unit. Preferably, the control unit 500 may be a CAN (Controller Area Network), HPGP (Homeplug Green Phy, To 28 MHZ bandwidth) can be realized.

CAN is a vehicle network that provides digital serial communication between automobile measurement and control equipment. By replacing complicated electric wiring and relay of electronic parts in vehicle with serial communication line, intelligence can reduce heavy weight and complexity and enable real time data communication have.

The HPGP is based on the IEEE 1901 standard, which means a network protocol that can be used for interworking between electric vehicles and home appliances in preparation for the spread of electric vehicles in recent years.

In this way, when the control unit 500 controls the energy supply unit 100 or the sensing unit, the control unit 500 can implement the CAN or HPGP scheme so that it can be widely compatible without replacing the conventional infrastructure as much as possible.

The control unit 500 of the present invention basically operates to change the charging mode by controlling the energy supply unit 100 and receives the measurement values from the current sensing unit 410 or the voltage sensing units 420 and 430 When the measured value exceeds the preset value, that is, when an overcurrent or an overvoltage condition occurs, the energy supply unit 100 is controlled to stop charging.

Meanwhile, the control unit 500 can drive the bidirectional charging system variously by issuing various control commands in addition to the above control.

In one embodiment, the control unit 500 may automatically change the charging mode to a predetermined time zone. Generally, the electric energy supplied in the night time zone is relatively low in cost, and the electric energy supplied in the daytime zone is relatively high, and the control unit 500 is connected to the electric vehicle in the middle of the night time zone (11:00 am, If the electric car is connected during the daytime (6:00 AM to 8:00 PM), it can be set as the reverse charging mode (electric car → energy supply).

In another embodiment, the control unit 500 determines the amount of electric energy remaining in the battery unit 200 of the electric vehicle, and if the amount of electric energy remaining in the battery unit 200 is greater than the set value, If it remains below the value, it can be set to the forward charge mode (energy supply unit → electric car).

1, a bidirectional charging system according to the present invention has been described.

3 illustrates an embodiment in which the switches 610 and 620 are further included in the bidirectional charging system described above.

The bidirectional charging system may further include switches 610 and 620 on the anode bus bar 310, the cathode bus bar 330 or the cathode bus bar 330, As shown in Fig. 3, both ends thereof are provided so as to extend to the bus bar.

The switches 610 and 620 are preferably connected to the control unit 500 to receive a control command of the control unit 500. When an overcurrent or an overvoltage is detected, the control unit 500 controls the switches 610, 620 may be driven to stop charging.

In the bidirectional charging system having the switches 610 and 620, the voltage sensing units 420 may be provided to measure voltages at both ends of the switches 610 and 620 based on the positions of the switches 610 and 620. 3, the bus bar voltage connected to one end of the switches 610 and 620 is connected to the first voltage sensing unit 420 and the bus bar voltage connected to the other ends of the switches 610 and 620 is connected to the second voltage sensing unit 430 The voltage sensing units 420 and 430 may be provided.

In the case where the voltage sensing units 420 and 430 are installed as described above, it is easy to know whether the voltages of the bus bars connected to the respective ends of the switches 610 and 620 indicate abnormal values. In addition, when the overvoltage phenomenon occurs, the switches 610 and 620 of the corresponding stage may be driven to quickly disconnect the circuit.

On the other hand, the switches 610 and 620 may further include an arc prevention device. An arc is a phenomenon in which a strong voltage is generated between two electrodes in the air due to an electrical contact failure or the like. In the case of an arc, a connected circuit generally suffers a large damage.

The present invention further minimizes the damage caused by the generation of an arc by providing an arc prevention device. Preferably, the arc prevention device is provided to be interlocked with the switches 610 and 620 so that the arc can be immediately switched off when an arc is generated . When the arc occurs, the switches 610 and 620 interlocked with the arc prevention device must be switched off regardless of the control command of the controller 500.

Figure 4 shows a bidirectional charging method according to the present invention in order.

4, the bidirectional charging method basically comprises the steps of i) supplying energy to the battery unit 200 by the energy supplying unit 100 or supplying electric energy from the battery unit 200 to the energy supplying unit 100 according to the charging mode, (S420); ii) a second step S430 of sensing the magnitude of the current or voltage on the bus bar to which electrical energy is transferred; iii) stopping the supply of the electric energy if the sensed current or voltage is equal to or greater than a preset value (S440, S450).

In order to avoid duplicated description, the description of the bidirectional charging system of FIGS. 1 to 3 will be referred to for the detailed steps 1 to 3.

The controller 500 in the bi-directional charging system determines whether the current time zone is the night time zone or the daytime zone in advance (S410), or if the battery unit 200 of the connected electric vehicle 200 It is possible to determine whether or not electric energy remains above a certain value or whether electric energy remains below a predetermined value. If the condition in the above-described step is satisfied, the control unit 500 performs charging of the electric vehicle battery unit 200 or back-charging to the energy supply unit 100 by performing the above-described first to third steps.

The bidirectional charging system according to the present invention has been described above. The embodiments of the present invention described above are disclosed for the purpose of illustration, and the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention.

100 energy supplier
110 network
200 battery part
310 anode bus bar 330 cathode bus bar
400 sensing unit
410 Current sensing unit
420 and 430,
500 controller
610, 620 switch

Claims (9)

An energy supply unit for supplying electric energy to the battery unit or supplying electric energy from the battery unit according to a charging mode;
A bus bar connecting the energy supply unit and the battery unit, and transferring electrical energy between the energy supply unit and the battery unit;
A sensing unit for sensing a magnitude of a current or a voltage of the bus bar;
A controller for controlling the energy supply unit and the sensing unit;
Lt; RTI ID = 0.0 >
The method according to claim 1,
Wherein the bus bar comprises a positive bus bar and a negative bus bar.
3. The method of claim 2,
A switch connected to both ends of the line of the anode bus bar or the cathode bus bar and driven in an opened or closed state according to a control command of the controller;
Lt; RTI ID = 0.0 > 1, < / RTI >
The method of claim 3,
Wherein the switch further comprises an arc protection device for breaking the connection between the switch and the bus bar upon over-current or over-voltage sensed.
The method of claim 3,
Wherein the sensing unit includes a current sensing unit,
Wherein the current sensing unit senses a current size of the positive bus bar or the negative bus bar.
The method of claim 3,
Wherein the sensing unit includes a voltage sensing unit,
Wherein the voltage sensing unit senses a voltage difference between the positive bus bar and the negative bus bar.
The method according to claim 6,
The switch including a first switch connected on the line of the positive bus bar and a second switch connected on the line of the negative bus bar,
The voltage sensing unit may include a first voltage sensing unit sensing a voltage difference of a bus bar extending from one end of the first switch and a second switch, and a second voltage sensing unit sensing a voltage of a bus bar extending from the other end of the first switch and the second switch, And a second voltage sensing unit for sensing the vehicle.
The method according to claim 1,
A DC filter connected to one end of the energy supply unit and removing an AC component of electric energy supplied from the energy supply unit to the battery unit;
Lt; RTI ID = 0.0 > 1, < / RTI >
(a) receiving energy from an energy supply unit to a battery unit or supplying energy from the battery unit to the energy supply unit according to a charging mode;
(b) sensing a magnitude of a current or voltage on a bus bar to which the electrical energy is transferred;
(c) driving the switch provided on the bus bar in an open state when the magnitude of the current or voltage sensed in step (b) is equal to or greater than a predetermined value;
≪ / RTI >

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