Charging system

Abstract

To provide a power supply system that can prevent a situation where an imbalance between three phases occurs and can suppress the instability of an electric power system, and to provide a three-single phase inverter used for the system.SOLUTION: The present invention relates to a charging system that can perform fast charging to an electric vehicle and / or a battery system while supplying an electric power to each user's house from a commercial system. The charging system comprises: a three-phase wiring and / or a single-phase wiring for drawing the electric power into the user's house from a pole transformer arranged in the commercial system; ACDC converters corresponding to the number of distribution lines; and one or more DCAC inverters connected to the subsequent stage of the ACDC converter. In the charging system, the fast charging with DC is performed through parallel-connection of the electric vehicles and / or the battery systems by being branched from the distribution line connecting the ACDC converter to the DCAC converter.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a charging system that rapidly charges an electric vehicle and / or a battery system while supplying power to each customer.

Background Art

[0002] The problem of carbon dioxide, which is considered to be the cause of global warming, is becoming more serious year by year. Amid the proposal of carbon neutrality, the spread of electric vehicles is desired. However, while the spread of electric vehicles is progressing in foreign countries, the current situation in Japan is that it is not progressing as expected. One of the reasons for this is the lack of charging infrastructure. Although the number of ordinary households equipped with charging facilities is increasing, it is not realistic for ordinary households to equip themselves with rapid charging facilities because the equipment investment cost is high. If it is impossible to charge at home, it is inconvenient to use, and it is natural that the spread will not progress. FIG. 10 is a conceptual diagram showing the current situation of electric vehicle charging in current ordinary households. Although the battery capacity and electricity cost are calculated based on standard levels, they are only examples. Since it is ordinary charging, it takes a certain amount of time to complete charging, and it can be understood that the electricity cost also increases to a certain extent. In addition, in Japan where the power generation ratio by renewable energy is not high, the fact that electric vehicles are not considered to be truly zero-emission may also be one of the reasons why the spread does not progress. Although electric vehicles do not emit any exhaust gas during driving, considering how electricity is generated, it may seem meaningless. If electricity is generated only by renewable energy such as solar power and wind power, or by hydropower and nuclear power, the exhaust gas will approach zero as much as possible. However, looking at the power supply situation in Japan, especially the high proportion of thermal power generation in Japan, it will be concluded that carbon neutrality will not progress even if the number of electric vehicles increases. Incidentally, regarding Japan's electricity supply situation, since not all consumers, such as houses and buildings, are located near power plants, electricity is transmitted and distributed via three-phase alternating current (AC) through high-voltage distribution lines, which are advantageous for supplying electricity over long distances. The three-phase power transmitted through the transmission and distribution network is converted into single-phase power by pole-mounted transformers (pole-mounted transformers) installed on utility poles, and then supplied as single-phase AC to consumers, such as houses and buildings. Figure 11 illustrates this process. Although only one consumer is shown as a representative example, in reality, one pole-mounted transformer supplies power to multiple consumers. Figure 11(a) shows how single-phase 100V power is supplied via two lines, and Figure 11(b) shows how single-phase 100V and single-phase 200V power are supplied via three lines. Specifically, the single-phase AC (2-wire and 3-wire) supplied to each consumer is generated by taking one pair of three phases (U-phase and V-phase, V-phase and W-phase, and U-phase and W-phase) as a single system and passing it through a pole-mounted transformer. Although not shown in the diagram, it is not uncommon for factories and other business establishments to step down three-phase high-voltage power to three-phase 200V or 400V and supply it via a 3-wire or 4-wire system. Three-phase AC transmission efficiency is 1.8 times better than single-phase AC, resulting in lower transmission losses and environmental impact, making it suitable for supplying large amounts of power. For example, prior art similar to that shown in Figure 10 can be found in Japanese Patent Publication No. 2019-134660, which describes an electric vehicle charging device comprising an AC / DC inverter 21 that converts AC power branched from a distribution board 12 to DC power, a storage battery 3 that stores the DC power converted by the AC / DC inverter 21, a DC power output unit 5 for supplying the power stored in the storage battery 3 to charge an electric vehicle, and an outlet 6 for directly supplying AC power branched from the distribution board 21 to the electric vehicle. Although this charging device utilizes power stored in the storage battery for charging, the charging method without the storage battery is no different from the conceptual diagram shown in Figure 10. [Overview of the project] [Problems that the invention aims to solve]

[0003] Given the background technologies described above, it is easy to understand the desire for an environment where rapid charging is possible in ordinary households. Furthermore, while it goes without saying that we should promote the transition to renewable energy, it is also important to enable energy-efficient charging processes even under existing power generation methods.

[0004] This invention has been made in view of the above-mentioned requirements, and aims to provide a charging system that enables rapid charging in ordinary households and energy-efficient charging processing. [Means for solving the problem]

[0005] The present invention relates to a charging system that rapidly charges electric vehicles and / or battery systems while supplying power from the commercial grid to each consumer, comprising: three-phase wiring for drawing power from a transformer located in the commercial grid into the premises of each consumer; a number of AC / DC converters corresponding to the number of wires; and one or more DC / AC inverters connected downstream of the AC / DC converters, wherein the AC / DC converters and the DC / AC stomach The aforementioned problems are solved by a charging system characterized by the fact that an electric vehicle and / or battery system are connected in parallel by branching off from the wiring connecting the inverter, thereby enabling rapid charging using DC. [Brief explanation of the drawing]

[0006] [Figure 1] This is a system configuration diagram that comprehensively illustrates the charging system of the present invention, and is shown as an abstract functional block. [Figure 2] This is a functional block diagram of a charging system according to the first embodiment of the present invention. [Figure 3] This is a functional block diagram of a charging system according to a second embodiment of the present invention. [Figure 4] This is a system configuration diagram of a charging system according to a third embodiment of the present invention, and is shown as an abstract functional block. [Figure 5] This is a system configuration diagram of a charging system according to the fourth embodiment of the present invention, and is shown as an abstract functional block. [Figure 6] This is a system configuration diagram of a modified example of the charging system according to the fourth embodiment of the present invention, and is shown as an abstract functional block. [Figure 7] This is a system configuration diagram of a charging system according to the fifth embodiment of the present invention, and is shown as an abstract functional block. [Figure 8] This is a system configuration diagram of a charging system according to the sixth embodiment of the present invention, and is shown as an abstract functional block. [Figure 9] This is a conceptual diagram illustrating rapid charging of an electric vehicle using the first embodiment of the present invention. [Figure 10] This is a conceptual diagram illustrating the current state of electric vehicle charging in typical households. [Figure 11] This is an explanatory diagram showing conventional power supply methods. [Modes for carrying out the invention]

[0007] Embodiments of the present invention will be described below with reference to the drawings. The following drawings are for illustrative purposes only, and in order to make them easier to understand, some components that are not necessary for the explanation may be intentionally omitted. Also, for illustrative purposes, some components may be intentionally enlarged or reduced in size, and the drawings do not represent an accurate scale.

[0008] (Overall configuration illustrating the concept of a charging system) Figure 1 is a system configuration diagram of a charging system 100 according to an embodiment of the present invention. Power (three-phase power, single-phase power, or both) from the transmission and distribution network TD, which is a commercial high-voltage distribution line (high-voltage line), is drawn into the interior of each consumer's house. The drawn-in power is supplied to a power conditioner 100 (hereinafter referred to as "power conditioner 100"), which is composed of an ACDC converter 1 corresponding to the number of power wirings, and one or more DCAC inverters 2 connected downstream. The power conditioner 100 outputs single-phase power of single-phase 100V or single-phase 200V, supplying power to electrical equipment used in the residence. However, as it stands, the power conditioner 100 is merely a power supply system that supplies power to electrical equipment in the residence, and there is no need to convert it to DC with the ACDC converter 1 when the input from the transmission and distribution network TD is only single-phase power. It is meaningful when the input is three-phase power, but this will be explained later. In this embodiment of the present invention, the DC wiring is branched and connected to an electric vehicle charging and discharging system 3 that can perform normal charging of about 3kW or rapid charging according to standards such as CHAdeMO® or Chaoji. In this way, the power conditioner 100 effectively constitutes the charging system 100. In this embodiment, a battery charging / discharging system 4 and a solar panel 5 are also arranged in parallel with the electric vehicle charging / discharging system 3, but their arrangement is optional. Furthermore, although the electric vehicle charging / discharging system 3 is depicted as a single block, it is possible to prepare multiple such systems to charge multiple vehicles, or to configure them to perform normal charging for vehicles that only support normal charging in addition to fast charging. In addition, the system may be configured to output power from the AC / DC converter 1 to the power transmission and distribution network TD for sale.

[0009] (First Embodiment) Figure 2 is a functional block diagram of a charging system according to the first embodiment of the present invention. The power conditioner 100 shown in Figure 2 is equipped with a power transmission and distribution network connection section 11 that is connected to low-voltage three-phase power converted from high-voltage three-phase power by a pole-mounted transformer (not shown) of the power transmission and distribution network TD (not shown), and from there three-phase three-wire power is drawn into the building of each consumer, and this power is supplied to the AC / DC converter 1. Alternatively, it is also possible to configure it to draw in high-voltage three-phase power as is. The AC / DC converter 1 is a three-phase full-wave rectifier circuit that uses rectifying elements such as diodes and thyristors to obtain a DC voltage from an AC voltage, and rectifies the difference voltage between the high and low phases of the three-phase sinusoidal AC voltage. The rectification may also have a PFC (Power Factor Correction) circuit to improve the power factor, or have functions for boosting and stepping up. The DC / AC inverter 2 converts the DC power into single-phase 100V or 200V AC, and its output is supplied to the indoor system connection section 21. Although it is depicted as a single block in Figure 2, it is actually composed of two inverters, one for 100V output and one for 200V output. Thus, it can be understood that the power conditioner 100, which is a charging system according to the first embodiment of the present invention, is a three-phase to single-phase inverter. The power conditioner 100 is mainly composed of semiconductor materials, specifically silicon semiconductors, but wide-bandgap semiconductors using materials such as GaN, SiC, and Ga2O3 may also be used.

[0010] The DC power obtained from the AC / DC converter 1 is supplied not only to electrical equipment used by consumers via the DC / AC inverter 2, but also directly to the electric vehicle charging / discharging system 3. Thus, the power conditioner 100 functions as a charging system. The electric vehicle charging / discharging system 3 is capable of performing normal charging of approximately 3kW, as well as rapid charging using standards such as CHAdeMO (registered trademark) and Chaoji. The voltage value of the DC power is appropriately set (48-1500V) to match the electric vehicle charging / discharging system 3 being used by adjusting the settings on the power conditioner 100. Until now, rapid charging of electric vehicles in ordinary households has not been implemented due to reasons such as the cost of installing equipment solely for charging not being justifiable. However, with this invention, charging equipment is provided as part of a power supply system, making it easier to implement.

[0011] The power conditioner 100, as a charging system according to the first embodiment of the present invention, also enables energy-efficient charging processing. The inventors have calculated that if the input for charging electric vehicles in detached houses (assuming 12kW) is changed from single-phase power to the three-phase input shown in Figure 2, the transmission loss between the house and the pole-mounted transformer can be reduced by approximately 50W per house. If this is calculated for 20 million detached houses, the instantaneous power can be reduced by 1 million kW (1 GW), which is equivalent to the amount of power used by the Oi Thermal Power Plant in Tokyo. If 20 million electric vehicles were fully charged every day, this would amount to a reduction of 387,000 tons of oil consumption.

[0012] In addition to this, the power conditioner 100 as a power supply system also has great significance. As shown in FIGS. 10(a) and (b), in the conventional power supply form, one pair is taken out of the three phases (between the U phase and the V phase, between the V phase and the W phase, between the U phase and the W phase). If the overall balance of power consumption of individual houses in a certain area is maintained, there will be no imbalance in the three-phase power. However, these days, there are family houses that are fully electrified, family houses equipped with electric vehicle charging facilities, and at the same time, there are houses where a single person lives and hardly uses electricity. Therefore, an imbalance in power consumption occurs among consumers, and it can be said that the risk of causing imbalances in phase and voltage in high-voltage three-phase power has increased compared to before. Under such circumstances, by many consumers in a specific area, more preferably, many consumers with large power consumption adopting the power conditioner 100 of the embodiment of the present invention, an increase in the imbalance rate of phase and voltage can be suppressed.

[0013] Furthermore, the power conditioner 100 of the embodiment of the present invention also contributes to copper neutral (reduction of copper consumption). When electric vehicles become popular, the demand for copper will increase rapidly. It is said that the importance of copper neutral will increase ahead of carbon neutral. The pole-mounted transformer (pole transformer) converts the three-phase three-wire system into a single-phase three-wire system or a single-phase two-wire system. The structure of the power conditioner 100 of the embodiment of the present invention has great significance. Since the pole transformer is made of windings, a large amount of copper and iron core materials are required. However, if three phases can be drawn into the home and a single phase can be generated by the power conditioner 100, the capacity of the pole transformer can be reduced, so the total number of pole transformers can be reduced, and the wire diameter of the copper wire can be made thinner, making it possible to reduce copper materials and iron core materials. This is because the power conditioner 100 uses semiconductor materials and does not use a large amount of windings equipped with copper and iron core materials.

[0014] Table 1 shows the relationship between the values of current with respect to power for different power supply methods.

Table 1

[0015] Returning to the description of the configuration of the first embodiment shown in FIG. 2. The ACDC converter 1 in FIG. 2 is configured to be able to sell electricity by outputting power to the power transmission and distribution network TD. However, recently, the attractiveness of selling electricity has been waning, and in the first embodiment, a battery charge and discharge system 4 for supplying power to electrical equipment used by customers other than automobiles is also provided. It is preferable to use a lithium-ion battery for the battery, but a lead battery, a battery using lithium titanate for the negative electrode material, a semi-solid battery, or an all-solid battery may also be used. Of course, if it corresponds to an electric vehicle, it is also possible to supply power from the electric vehicle charge and discharge system 3 to the electrical equipment.

[0016] Furthermore, the first embodiment can also be provided with power generation means. In FIGS. 1 and 2, it is shown as a solar panel 5, but this is an example, and other heat generation means such as an Enerfarm (registered trademark) or a windmill may be used instead of the solar panel. By the way, solar power generation itself is not very cost-effective because a power conditioner is prepared for its introduction, but according to the present invention, since the power conditioner can be used in common for all of solar power generation, charging of electric vehicles, and charging of other batteries, it becomes easier to introduce. In that sense, the present invention can also be regarded as an ideal DC power supply system that reduces power conversion loss and uses electricity efficiently.

[0017] (Second Embodiment) Figure 3 is a functional block diagram of a charging system according to a second embodiment of the present invention. The power conditioner 100 shown in Figure 3 is equipped with a power transmission and distribution network connection section 1A1 that is connected to low-voltage three-phase power converted from high-voltage three-phase power by a pole-mounted transformer (not shown) of the power transmission and distribution network TD (not shown), and from there three-phase three-wire power is drawn into the building of each consumer, and this power is supplied to the AC / DC converter 1A. Alternatively, it is also possible to draw in high-voltage three-phase power as is and supply it to the AC / DC converter 1A. The AC / DC converter 1A uses rectifying elements such as diodes and thyristors and is a three-phase full-wave rectifier circuit that obtains a DC voltage of 48 to 1500V from an AC voltage, and rectifies the difference voltage between the high and low phases of the three-phase sinusoidal AC voltage. The rectification may also have a PFC (Power Factor Correction) circuit to improve the power factor, or have functions for boosting and lowering the voltage. The configuration up to this point is the same as that of the first embodiment, but the power conditioner 100 of the second embodiment is further equipped with a power transmission and distribution network connection part 1B1 (single-phase connection part) in addition to the power transmission and distribution network connection part 1A1 (three-phase connection part). That is, the power transmission and distribution network connection part 1B1 (single-phase connection part) is converted by a pole-mounted transformer (not shown) of the power transmission and distribution network TD (not shown) and connected to a single-phase 200V power line prepared to be brought into the building of each consumer.

[0018] The second embodiment aims to mutually supplement power using the supply lines from the power transmission and distribution network connection section 1A1 (three-phase connection section) and the power transmission and distribution network connection section 1B1 (single-phase connection section). After the connection points of ACDC converters 1A and 1B, multiple DCAC inverters 2 are connected in parallel to obtain both single-phase 100V and single-phase 200V (however, they are depicted as a single block in the figure), and after these, indoor system connection sections 21 for single-phase 200V and single-phase 100V are connected respectively (however, they are depicted as a single block in the figure). When a temporary increase in power consumption is expected, auxiliary power is obtained from single-phase power. There is value in minimizing concentrated use of single-phase power and reducing the bias in single-phase power usage, but even if single-phase power is used, it is perfectly acceptable if it is for temporary and auxiliary use. The power conditioner 100 realized by these ACDC and DCAC is mainly composed of semiconductor materials, specifically silicon semiconductors, but wide-bandgap semiconductors using materials such as GaN, SiC, and Ga2O3 may also be used.

[0019] In the second embodiment, the system may be configured to automatically supplement power from single-phase 200V when it detects that power is being used up to the power usage limit of the three-phase power, or when it detects that power is being used up to an arbitrarily set predetermined value. That is, a power addition determination means (not shown) is provided to monitor whether the three-phase power is approaching the power usage limit, and the system is controlled to supply additional single-phase 200V power. Alternatively, a predetermined value that is a certain degree lower than the usage limit may be used as the criterion for determining the additional power supply.

[0020] The electric vehicle charging / discharging system 3 is the same as in the first embodiment, and the voltage (48-1500V) corresponding to the electric vehicle charging / discharging system 3 being used is set appropriately by operating the power conditioner 100. The battery charging / discharging system 4 and solar panel 5 are also the same as in the first embodiment and will be installed as appropriate according to the specifications required by the customer.

[0021] (Third embodiment) The third embodiment will be described based on Figure 4, a system configuration diagram shown as an abstract functional block. In Figure 4, the wiring from the power transmission and distribution network TD to the AC / DC converter 1 should be understood as comprehensively representing the first and second embodiments, that is, encompassing both the configuration with only three-phase connection and the configuration with both three-phase and single-phase connection. The difference between the third embodiment and the first and second embodiments is that a DC / DC converter 6 is inserted after the AC / DC converter 1 as a component of the power conditioner 100. The DC / DC converter 6 may be configured as an isolated DC / DC or an unisolated DC / DC, and the input / output relationship of the DC / DC converter 6 may be a boost, buck, or equal voltage relationship. In the third embodiment, the DC / DC converter 6 is configured to vary the voltage value in order to accommodate a voltage-variable electric vehicle charging and discharging system 3 that can perform normal charging of about 3kW to rapid charging according to standards such as CHAdeMO® and Chaoji. In other words, the voltage value is adjusted to correspond to the rated power of the electric vehicle or charging device. However, Figure 4 is just one example, and essentially, the point is to include a DC-DC converter, and this does not exclude the possibility of voltage conversion to obtain a semi-fixed or completely fixed voltage.

[0022] In addition to this, the voltage value is also adjusted to be smaller than the rated power range of the electric vehicle or charging device. That is, the system is configured to monitor the power consumption of electrical equipment used by the consumer and adjust the maximum value of the electric vehicle's charging power according to the power limit from the commercial grid. It would be counterproductive if household electrical equipment could not be used in order to charge the electric vehicle, and if charging could not be done while a large amount of electrical equipment is being used, the objective of the present invention, which is to enable rapid charging, would be undermined. Therefore, in the third embodiment, the system is designed to balance the use of electrical equipment and the charging of the electric vehicle. In other words, the third embodiment can be said to realize a function that adjusts the electric vehicle's charging power when the sum of the three-phase and single-phase input power exceeds the power usage limit. Although not shown in the figures, an ampere breaker is placed between the power transmission and distribution network TD and the AC / DC converter 1 (see also Figure 7 of the fifth embodiment described later), and appropriate sensors are installed around the ampere breaker to monitor the amount of power used.

[0023] (Fourth embodiment) Figure 5 is a system configuration diagram of a charging system according to the fourth embodiment of the present invention, and is shown as an abstract functional block. The fourth embodiment shares the same basic concept as the third embodiment, but the location where the DC-DC converter 6 is installed differs from that of the third embodiment. Furthermore, in the third embodiment, the DC-DC converter 6 was an essential component of the power conditioner 100, but in the fourth embodiment, given its wiring location, it is not necessarily an essential component and can be configured as an element within the power conditioner 100 or as a separate system from the power conditioner 100. In other words, the DC-DC converter 6 can be retrofitted to the systems of the first and second embodiments, which is advantageous in that it allows for phased equipment installation. Further modifications are shown in Figure 6. In short, this is an example that incorporates elements from both the third and fourth embodiments, in which the DC-DC converter 6 is placed either downstream of the AC-DC converter 1 or upstream of the electric vehicle charging / discharging system 3. Because it combines both the voltage conversion means for the entire DC power supply system and the individual voltage conversion means for electric vehicle charging, fine-grained adjustments are possible. In addition, the DC-DC converter 6 is placed in two stages upstream of the electric vehicle charging / discharging system 3 in order to flexibly accommodate a wide range of charging standards.

[0024] (Fifth embodiment) The electric vehicle charging system 3 connected to the power conditioner 100 in the first to fourth embodiments described above, or the battery system 4 and solar panel 5 which are installed as options, can be described as DC power supply systems. However, the fifth embodiment adds a conventional AC system to this. In other words, there are also AC-type charging devices for electric vehicles, and this can be accommodated. Figure 7 is a system configuration diagram of the charging system according to the fifth embodiment of the present invention, and is shown as an abstract functional block. As shown in the figure, an ampere breaker AB is inserted between the power transmission and distribution network TD and the AC / DC converter 1, and an AC system charging and discharging system is constructed by branching from the downstream of the ampere breaker AB. In addition to the electric vehicle charging and discharging system 3, battery charging and discharging system 4 and solar panel 5 in the power conditioner 100, an AC system electric vehicle charging and discharging system, battery charging and discharging system and solar panel are provided separately. From this, it can be understood that even when loads or power generation means are connected to the conventional system, it is possible to control the system so as not to exceed the capacity of the ampere breaker.

[0025] When electricity is used up to the maximum power capacity of the ampere breaker AB, the battery charging / discharging system 4 and the AC-system battery charging / discharging system are discharged to increase the charging power of the electric vehicle and adjust it to enable charging. Furthermore, even if a power outage occurs and power cannot be drawn from the transmission and distribution network, the circuit breaker is not manually tripped. Instead, the AC / DC converter 1 disconnects from the transmission network, and single-phase 100 / 200V power can be supplied to operate household appliances connected to the indoor system by the battery charging / discharging system 4 electrically connected to the power conditioner 100, or by the battery or solar panel power generation means installed in the electric vehicle. This is, in a sense, also assumed in the first to fourth embodiments, but in the fifth embodiment, it is also possible to utilize the AC system. If the power conditioner 100 malfunctions, the disconnection and connection by the AC / DC converter 1 and / or DC / AC inverter 2 can be controlled sequentially.

[0026] In this fifth embodiment, where the battery charging and discharging system is so well-equipped, the power supply can be switched by comparing the three-phase AC contracted power with the power consumption, storing power in the battery when the power consumption is sufficiently low, and replenishing power from the battery when the power consumption exceeds the contracted power.

[0027] (Sixth Embodiment) Up until now, only one input system has been considered (the combined use of three-phase and single-phase power is understood to be one system), but configurations with multiple input systems can also be envisioned. Figure 8 is a system configuration diagram of a charging system according to the sixth embodiment of the present invention, and is shown as an abstract functional block. The sixth embodiment, like the fifth embodiment, has not only DC but also AC systems, but has two input systems. These two input systems may be independently three-phase, single-phase, or a combination of both. The sixth embodiment is also based on the provision of an electric vehicle charging and discharging system, and the sum of the electric vehicle charger's power consumption and the power consumption of electrical equipment is controlled so as not to exceed the input power, that is, so as not to exceed a certain amount of power or so that the ampere breaker does not trip. For elements other than the basic configuration, the word "option" is added in the figure, and they are optional additional elements or configurations. For example, the power generation means is an optional additional element, and features such as power sales and charging / discharging are optional additional configurations. Note that in Figure 8, the numbers for each block have been omitted. Although not shown in the diagram, in the sixth embodiment, one or both systems may be configured without an electric vehicle charging / discharging system, and control may be performed to prioritize the use of power from the system that is preferred among the two systems. This has the advantage of allowing for advantageous usage according to the contracted electricity usage.

[0028] (Advantages of rapid charging according to embodiments of the present invention) Figure 9 is a conceptual diagram showing rapid charging of an electric vehicle using the first embodiment of the present invention. Earlier, Figure 10 was used to explain the current concept of electric vehicle charging. Figure 9 also assumes the same battery capacity as Figure 10, but the electricity charges are calculated based on the standard for a three-phase AC contract. The time to complete charging is shortened to about one-quarter, and the electricity cost is reduced by nearly half, so it is expected that this will further promote the spread of electric vehicles.

[0029] (Other embodiments) In addition, although not shown in the diagram, it is also conceivable that the input may be single-phase only. At first glance, it may seem pointless to use an AC / DC converter and a DC / AC inverter when the indoor system is single-phase 100 / 200V, but this is not the case. This is because constructing a DC power supply system using an electric vehicle charging / discharging system, a battery charging / discharging system, and solar panels reduces the total number of power converters, which is advantageous in terms of energy efficiency. Furthermore, while the main focus of this invention is the rapid charging of electric vehicles, embodiments that include only a battery charging and discharging system without an electric vehicle charging and discharging system are also conceivable. By monitoring the power consumption of electrical equipment used by consumers and adjusting battery charging according to the power limit from the commercial grid, it is possible to effectively use power within the limits stipulated in the electricity contract. Moreover, even if a mechanism is adopted to shut down electrical equipment with lower priority so that the sum of the power consumption of electrical equipment does not exceed the input power, and the connection to the battery is eliminated altogether, this can be conceived as a promising technological concept.

[0030] Although the charging system according to embodiments of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments, and any design changes, etc., that do not depart from the gist of the present invention are also included. For example, while embodiments for three-phase 200V and three-phase 400V have been described, embodiments that include three-phase 600V and combine these as appropriate are also possible. [Explanation of Symbols]

[0031] 100 Power Conditioner (Charging System) 1 AC / DC converter 1A AC / DC converter 1B AC / DC converter 1A1 Power transmission and distribution network connection section (three-phase) 1B1 Power transmission and distribution network connection section (single phase) 2 DC-AC inverters 21 Indoor system connection section 3. Electric Vehicle Charging and Discharging System 4. Battery charging and discharging system 5. Solar panels (means of power generation) 6 DC-DC converters TD transmission and distribution network AB Ampere Breaker

Claims

1. A charging system that supplies electricity from the commercial grid to each consumer while rapidly charging electric vehicles and / or battery systems, It comprises three-phase wiring for drawing power from a transformer located in the commercial grid into the interior of each customer's house, a number of ADC converters corresponding to the number of wires, and one or more DC-AC inverters connected downstream of the ADC converters. A charging system characterized by performing rapid charging in DC by connecting an electric vehicle and / or a battery system in parallel via a branch from the wiring connecting the ADC converter and the DC-AC inverter.

2. A DC-DC converter is installed between the ADC converter and the electric vehicle and / or battery system. The charging system according to claim 1, characterized in that the charging voltage is varied by the DC-DC converter.

3. Furthermore, it includes a control unit. The charging system according to claim 2, characterized in that the control unit monitors the amount of power used by electrical equipment used by the customer and adjusts the maximum value of the electric vehicle's charging power according to the power limit from the commercial grid.

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