Power supply system

Abstract

To supply power from a vehicle to a power load with a simple system configuration.SOLUTION: In the power supply system 101, the power supply device 3 supplies AC power from the vehicle 4 to the load 123 when the vehicle 4 is connected. The first electromagnetic switch 51 can switch between electrical connection and disconnection between the earth leakage breaker 1 and the overcurrent breaker 113. The second electromagnetic switch 52 can switch electrical connection and disconnection between the first electromagnetic switch 51 and the power supply device 3, and can switch electrical connection and disconnection between the overcurrent breaker 113 and the power supply device 3. The ammeter 130 measures a current value between the overcurrent breaker 113 and the load 123. The power supply system 101 closes the first electromagnetic switch 51 and opens the second electromagnetic switch 52 when the vehicle 4 is connected to the power supply device 3 and the measurement value measured by the ammeter 130 exceeds the threshold value β.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to power supply systems. [Background technology]

[0002] In a power supply system capable of supplying power from a grid power source to a residential power load, power from a vehicle can be supplied to the power load primarily in emergencies (such as when the grid power source is out of power or when the grid power source is under power pressure). In addition, it has also been proposed to supply power from a vehicle to a power load on a daily basis (such as during times when the grid power source's electricity rates are high). Japanese Patent Application Laid-Open Publication No. 2019-71721 (Patent Document 1) discloses a power supply system capable of utilizing power stored in an electric vehicle during a power outage. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-71721 Summary of the Invention [Problem to be solved by the invention]

[0004] The AC power supplied from the grid power supply and the AC power supplied from the vehicle are out of phase with each other. Therefore, it is not desirable to simultaneously supply AC power from the grid power supply and AC power from the vehicle to the power load. It is desirable to be able to supply power from the vehicle to the power load with as simple a system configuration as possible.

[0005] The present disclosure has been made to solve the above-mentioned problems, and one of the objects of the present disclosure is to provide a power supply system that can supply power from a vehicle to an electric load with a simple system configuration. [Means for solving the problem]

[0006] A power supply system according to an aspect of the present disclosure supplies AC power from a grid power supply to a power load in a house. The power supply system includes a current breaker, a load breaker, a power conversion device, a first switch, a second switch, and a meter. The current breaker receives AC power from the grid power supply to the house and interrupts the power in at least one of an earth leakage current and an overcurrent. The load breaker is configured to electrically interrupt the connection between the current breaker and the power load. The power conversion device is configured to supply AC power from a vehicle to the power load when the vehicle is connected. The first switch is configured to be able to switch between electrical connection and interruption between the current breaker and the load breaker. The second switch is configured to be able to switch between electrical connection and interruption between the first switch and the power conversion device, and to switch between electrical connection and interruption between the load breaker and the power conversion device. The meter measures at least one of a current value, a voltage value, and a power value between the load breaker and the power load. The power supply system closes the first switch and opens the second switch when the vehicle is connected to the power conversion device and the measurement value measured by the measuring instrument exceeds a threshold value. [Effects of the Invention]

[0007] According to the present disclosure, power can be supplied from a vehicle to an electric load with a simple system configuration. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a circuit block diagram showing a first example of the configuration of a power supply system according to a first embodiment. [Figure 2] 4 is a circuit block diagram showing a second example of the configuration of the power supply system according to the first embodiment. FIG. [Figure 3] 6 is a flowchart showing a first example of a processing procedure relating to control of an electromagnetic switch. [Figure 4] FIG. 10 is a circuit block diagram showing a first example of the configuration of a power supply system according to a second embodiment. [Figure 5]FIG. 10 is a circuit block diagram showing a second example of the configuration of the power supply system according to the second embodiment. [Figure 6] FIG. 10 is a circuit block diagram showing a third example of the configuration of the power supply system according to the second embodiment. [Figure 7] FIG. 10 is a circuit block diagram showing a fourth example of the configuration of the power supply system according to the second embodiment. [Figure 8] 10 is a flowchart showing a second example of a processing procedure relating to control of the electromagnetic switch. [Figure 9] 10 is a flowchart showing a third example of a processing procedure relating to control of an electromagnetic switch. [Figure 10] 4 is a circuit block diagram showing a modification of the first example of the configuration of the power supply system according to the first embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals, and description thereof will not be repeated.

[0010] [Embodiment 1] <System configuration> 1 is a circuit block diagram showing a first example of the configuration of a power supply system according to the first embodiment. The power supply system 101 supplies power from a power grid 900 to a load in a house 101A. The house 101A is typically a residence (a building where people live). However, the house 101A may also include non-residential buildings, such as buildings and structures that house equipment. The load is, for example, various types of electrical equipment, and may be located inside (indoors) or outside (outdoors) the house 101A.

[0011] The power supply system 101 includes an earth leakage breaker 1, overcurrent breakers 111 to 113, 211, and 212, a power supply device 3, and an ammeter 130. The number of overcurrent breakers is not particularly limited. The ammeter 130 is an example of a "measuring instrument" in the present disclosure.

[0012] The earth leakage breaker 1 receives AC power from the power grid 900 to the house 101A. An electric circuit PL1 for transmitting AC 100V power and an electric circuit PL2 for transmitting AC 200V power are connected to the earth leakage breaker 1. When a ground fault is detected, the earth leakage breaker 1 electrically cuts off the connection between the power grid 900 and the electric circuits PL1 and PL2. The earth leakage breaker 1 corresponds to the "current circuit breaker" according to the present disclosure.

[0013] The overcurrent breakers 111-113 are electrically connected to an AC 100V electrical circuit PL1. Although not shown, the house 101A includes multiple rooms. For example, a load 121 is provided in one room, a load 122 is provided in another room, and a load 123 is provided in yet another room. The overcurrent breakers 111-113 are provided corresponding to different rooms in the house 101A. The overcurrent breakers 111-113 are configured to electrically disconnect the earth leakage breaker 1 and the loads 121-123, respectively, upon detecting an overcurrent. The overcurrent breaker 113 corresponds to a "load breaker" according to the present disclosure. Each load corresponds to a "power load" according to the present disclosure.

[0014] The overcurrent breakers 211 and 212 are electrically connected to the AC 200V electric circuit PL2. The overcurrent breakers 211 and 212 are installed in different rooms of the house 101A, similar to the AC 100V overcurrent breakers 111 to 113. The overcurrent breakers 211 and 212 are configured to electrically cut off the connection between the earth leakage breaker 1 and the loads 221 and 222, respectively, when an overcurrent is detected.

[0015] The power supply device 3 is configured to be connected to the vehicle 4 via a power supply cable (not shown). The vehicle 4 is an electric vehicle equipped with a driving battery and capable of supplying and receiving power from outside the vehicle, specifically a BEV (Battery Electric Vehicle) or a PHEV (Plug-in Hybrid Electric Vehicle). The power supply device 3 includes an AC / DC conversion device, and is configured to supply AC power from the vehicle 4 to a load (load 123 in this example) when the vehicle 4 is connected. The power supply device 3 is an example of a "power conversion device" according to the present disclosure.

[0016] The ammeter 130 measures the value of a current flowing between the overcurrent breaker 113 and the load 123. Note that instead of an ammeter, a voltmeter that measures a voltage value or a wattmeter that measures a power value may be provided. Also, two or all of the ammeter, voltmeter, and wattmeter may be provided.

[0017] The power supply system 101 further includes a first electromagnetic switch 51, a second electromagnetic switch 52, and a controller .

[0018] A first end of the first electromagnetic switch 51 is electrically connected to the AC 100V electrical circuit PL1. A second end of the first electromagnetic switch 51 is electrically connected to the overcurrent breaker 113. As a result, the first electromagnetic switch 51 is configured to switch between electrical connection and disconnection between the earth leakage breaker 112 and the overcurrent breaker 113 in accordance with a control command from the controller 10.

[0019] A first end of the second electromagnetic switch 52 is electrically connected to a second end of the first electromagnetic switch 51 and is also electrically connected to the overcurrent breaker 113. The second end of the second electromagnetic switch 52 is electrically connected to the power supply device 3. As a result, the second electromagnetic switch 52 is configured to switch between electrical connection and disconnection between the first electromagnetic switch 51 and the power supply device 3, and between electrical connection and disconnection between the overcurrent breaker 113 and the power supply device 3, in accordance with a control command from the controller 10.

[0020] Although not shown, the earth leakage breaker 1 and the overcurrent breakers 111-113, 211, 212 are provided in a distribution board (which may be a switchboard depending on the type of house 101A). If the distribution board is large, the first electromagnetic switch 51 and the second electromagnetic switch 52 may be arranged inside the distribution board. If the distribution board is small, the first electromagnetic switch 51 and the second electromagnetic switch 52 may be attached externally to the distribution board and arranged in a housing provided near the distribution board.

[0021] The first electromagnetic switch 51 corresponds to the "first switch" according to the present disclosure, and the second electromagnetic switch 52 corresponds to the "second switch" according to the present disclosure. The first electromagnetic switch 51 and the second electromagnetic switch 52 are also collectively referred to as the "electromagnetic switch."

[0022] The controller 10 is a computer device including a processor 11 and a memory 12, and is, for example, a HEMS (Home Energy Management System) controller. The controller 10 outputs a control command to open and close (switch on / off) each of the first electromagnetic switch 51 and the second electromagnetic switch 52. As will be described later, the controller 10 may be capable of acquiring power information (such as power transaction information and electricity rate information) of the grid power supply 900 from an energy management server (not shown), and opening and closing the first electromagnetic switch 51 and the second electromagnetic switch 52 and controlling the power supply device 3 (i.e., causing power to be supplied from the vehicle 4) in accordance with the acquired power information. The controller 10 corresponds to a "control device" according to the present disclosure.

[0023] There is a phase difference between the AC power supplied from system power supply 900 and the AC power supplied from vehicle 4. Therefore, it is not preferable to simultaneously supply AC power from system power supply 900 and AC power from vehicle 4 to loads 121 to 123. According to the first embodiment, first electromagnetic switch 51 and second electromagnetic switch 52 can be used to select which of the two AC powers to supply to loads 121 to 123.

[0024] Fig. 2 is a circuit block diagram showing a second example of the configuration of the power supply system according to embodiment 1. To avoid cluttering the drawings, the house 101A and the controller 10 are omitted from Fig. 2 onwards.

[0025] The power supply system 102 shown in FIG. 2 differs from the power supply system 101 shown in FIG. 1 in that the first electromagnetic switch 51 is electrically connected to the electrical circuit PL1 for AC 100V, and the second electromagnetic switch 52 is electrically connected to the electrical circuit PL1 for AC 100V.

[0026] In the power supply system 101 shown in FIG. 1, a first electromagnetic switch 51 is provided in a position corresponding to the upstream of the overcurrent breaker 113. Therefore, only the overcurrent breaker 113 is disconnected from the earth leakage breaker 1 by opening and closing the first electromagnetic switch 51. On the other hand, the first electromagnetic switch 51 shown in FIG. 2 is provided not only in a position corresponding to the upstream of the overcurrent breaker 113, but also in a position corresponding to the upstream of the overcurrent breakers 111 and 112 in the other rooms. Therefore, when the first electromagnetic switch 51 opens, the first electromagnetic switch 51 disconnects all three overcurrent breakers 111 to 113 from the earth leakage breaker 1.

[0027] As described above, as long as it is possible to switch between electrical connection and disconnection between the earth leakage breaker 1 and at least one overcurrent breaker, there are no limitations on the placement of the first electromagnetic switch 51. The first electromagnetic switch 51 may be placed anywhere as long as it is possible to switch between connection and disconnection between the earth leakage breaker 1 and at least one of the overcurrent breakers 111 to 113.

[0028] Additionally, in the second example, the first terminal of the second electromagnetic switch 52 is electrically connected to the AC 100V electric circuit PL1 (i.e., single-phase three-wire). This allows AC power from the vehicle 4 to be supplied not only to the load 123 but also to the other loads 121 and 122.

[0029] The configuration of power supply system 102 other than the arrangement of first electromagnetic switch 51 and second electromagnetic switch 52 is similar to the corresponding configuration of power supply system 101, and therefore detailed description thereof will not be repeated.

[0030] In addition, another electromagnetic switch (not shown) instead of the first electromagnetic switch 51 may be electrically connected, for example, between the overcurrent breaker 113 and the load 123 (in other words, at a position corresponding to the downstream of the load 123).

[0031] <Processing flow> 3 is a flowchart showing a first example of a processing procedure for controlling an electromagnetic switch. The processing shown in this flowchart is executed when a predetermined condition is met (for example, at predetermined intervals). Each step is realized by software processing by the controller 10 (processor 11), but may also be realized by hardware (electrical circuitry) arranged within the controller 10. Hereinafter, steps are abbreviated as S. This also applies to other flowcharts described later.

[0032] Here, the explanation will be given taking the power supply system 101 shown in Fig. 1 as an example. It is assumed that at the start of a series of processes, the first electromagnetic switch 51 is on (closed) and the second electromagnetic switch 52 is off (open).

[0033] 1 and 3, in S100, the controller 10 determines whether or not the power supply device 3 is connected to the vehicle 4. If the power supply device 3 is connected to the vehicle 4 (YES in S100), the controller 10 proceeds to S101. If the power supply device 3 is not connected to the vehicle 4 (NO in S100), the controller 10 ends the process. Note that the process of S100 may be omitted.

[0034] In S101, the controller 10 acquires power information (current electricity rate information in this example) of the system power supply 900 from, for example, an energy management server (not shown).

[0035] In S102, the controller 10 determines whether the current electricity price acquired in S101 is higher than the reference price (for example, the average price of electricity on that day). If the current electricity price is higher than the reference price (YES in S102), the controller 10 proceeds to S103.

[0036] In S103, the controller 10 acquires the state of charge (SOC) of the battery mounted on the vehicle 4 by communication with the vehicle 4 or the like. Then, the controller 10 determines whether the acquired SOC is higher than a required value (S104). The required value is, for example, a value corresponding to the amount of power required for the vehicle 4 to run the next day. The required value may be a predetermined fixed value or a variable value determined according to the usage history of the vehicle 4.

[0037] If the SOC is higher than the required value (YES in S104), the controller 10 advances the process to S105. If the SOC is equal to or lower than the required value (NO in S104), the controller 10 advances the process to S109.

[0038] In S105, the controller 10 acquires information on the electricity price from the previous time the vehicle 4 was charged, for example, from an energy management server (not shown). Then, in S106, the controller 10 calculates the difference between the current electricity price, the information of which was acquired in S101, and the electricity price from the previous time the vehicle 4 was charged, the information of which was acquired in S105, and determines whether the difference is equal to or greater than a threshold value α. If the difference is greater than the threshold value α (YES in S106), the controller 10 proceeds to S107. If the difference is equal to or less than the threshold value α (NO in S106), the controller 10 proceeds to S110. Note that, although the threshold value α is a positive value in this embodiment, the threshold value α may also be 0. Furthermore, although an example in which the difference is calculated has been shown in this embodiment, a determination equivalent to S106 may also be made based on, for example, the ratio of b to a (b / a) instead of the difference.

[0039] For the sake of explanation, let a and b denote the current electricity rate and the electricity rate at the previous charge, respectively. Let x denote the available power capacity in the load 123. Let L denote the amount of power consumed by the ECU or the like when charging the vehicle 4 (power loss). In this case, the revenue obtained by the user when the vehicle 4 discharges power to the load 123 is bx-ax-aL. For bx-ax-aL to be greater than 0, the condition (ba) > aL / x must be satisfied. That is, the smaller the difference between b and a, the larger the threshold value of x for the user to obtain revenue. The controller 10 may set aL / x to the threshold value α, or may set the sum of aL / x and an arbitrary value to the threshold value α. This makes it possible to prevent financial losses caused by power supply from the vehicle 4 to the load 123. The controller 10 may acquire information about x from the load 123. L may be a fixed value stored in the memory 12 (FIG. 1).

[0040] In S105, information on the electricity fee for the previous charging is acquired, but the present disclosure is not limited to this. For example, if the power currently stored in vehicle 4 is stored through multiple past charging operations, information on the average electricity fee for the multiple charging operations may be acquired.

[0041] In S107, the controller 10 determines whether the measurement value (current value) measured by the ammeter 130 is equal to or less than a threshold value β. The threshold value β is a value set so as not to exceed the discharge capacity of the vehicle 4 when power is supplied to the vehicle 4. The threshold value β may be a fixed value set in advance in the memory 12 or the like, or may be a value calculated each time based on the state of the vehicle 4 (for example, SOC, etc.). If the measurement value of the ammeter 130 is equal to or less than the threshold value β (YES in S107), the controller 10 proceeds to S108. If the measurement value of the ammeter 130 exceeds the threshold value β (NO in S107), the controller 10 proceeds to S110.

[0042] The controller 10 turns off the first electromagnetic switch 51 and turns on the second electromagnetic switch 52 (S108). Then, the controller 10 controls the power feeding device 3 so that power feeding from the vehicle 4 to the load 123 starts (S109), and the process returns to S103.

[0043] If power supply from vehicle 4 continues, the SOC decreases over time. When the SOC becomes equal to or lower than the required value (NO in S104), controller 10 controls power supply device 3 to terminate power supply from vehicle 4 to load 123 (S110). Then, controller 10 turns on first electromagnetic switch 51 and turns off second electromagnetic switch 52 (S111). This completes the series of processes.

[0044] As can be seen from the flow of Figure 3, when the processing of S107 is performed again after the processing of S108, if the detection value exceeds the threshold value β (NO in S107), in S111 the first electromagnetic switch 51 is switched from the off state to the on state, and the second electromagnetic switch 52 is switched from the on state to the off state.

[0045] Furthermore, when the processing of S108 is not performed, the first electromagnetic switch 51 is in the ON state, and the second electromagnetic switch 52 is in the OFF state, if the detection value exceeds the threshold value β in the processing of S107 (NO in S107), the ON state of the first electromagnetic switch 51 and the OFF state of the second electromagnetic switch 52 are maintained in S111. In other words, in this case, the opening (OFF) of the first electromagnetic switch 51 and the closing (ON) of the second electromagnetic switch 52 are prohibited.

[0046] As will be described later in a second embodiment, if a charging device is provided in addition to the power supply device 3, or if a bidirectional power conversion device is provided instead of the power supply device 3 (see FIGS. 4, 5, etc.), when the electricity rate is equal to or lower than the reference price (NO in S102), the controller 10 may control the charging device or the bidirectional power conversion device so that the vehicle 4 is charged (S112, S113).

[0047] 3, an example has been described in which the subsequent processing is changed depending on whether the electricity rate is higher than the reference price. Alternatively, the controller 10 may switch processing depending on whether the current time is a nighttime period (a time period in which a nighttime rate is applied). This also allows for savings on electricity rates.

[0048] Alternatively, controller 10 may switch processing depending on whether the current time is a time zone in which the power demand of house 101A is at its peak. By supplying power from vehicle 4 during a time zone in which the power demand is at its peak, the peak power demand can be met even if the maximum supply current from grid power supply 900 is low, and so the so-called contracted ampere number can be reduced. This allows for savings on electricity charges.

[0049] As described above, in the first embodiment, the power supply systems 101, 102 include the first electromagnetic switch 51 and the second electromagnetic switch 52. By using the first electromagnetic switch 51 and the second electromagnetic switch 52, it is possible to select whether the AC power from the grid power supply 900 or the AC power from the vehicle 4 is to be supplied to the loads 121-123. More specifically, by turning on the first electromagnetic switch 51 and turning off the second electromagnetic switch 52, the AC power from the grid power supply 900 is selected. On the other hand, by turning off the first electromagnetic switch 51 and turning on the second electromagnetic switch 52, the AC power from the vehicle 4 is selected. Thus, according to the first embodiment, power from the vehicle 4 can be supplied to the loads with a simple system configuration that requires only the addition of two electromagnetic switches.

[0050] In addition, by turning off the second electromagnetic switch 52 and turning on the first electromagnetic switch 51 when the detection value of the ammeter 130 exceeds the threshold value β, it is possible to prevent power from being supplied from the vehicle 4 to the load 123 when there is a risk that the discharge capacity of the vehicle 4 will be exceeded.

[0051] [Embodiment 2] In the second embodiment, a configuration will be described in which a vehicle can be charged with power generated by a solar power generation device.

[0052] <System configuration> Fig. 4 is a circuit block diagram showing a first example of the configuration of a power supply system according to embodiment 2. A power supply system 201 shown in Fig. 4 differs from the power supply systems 101 and 102 (see Figs. 1 and 2) according to embodiment 1 in that the power supply system 201 further includes a third electromagnetic switch 53, a charging device 6, a power conditioner (PCS: Power Conditioning System) 7, and a solar power generation device 8.

[0053] A first end of the third electromagnetic switch 53 is electrically connected to the power conditioner 7. A second end of the third electromagnetic switch 53 is electrically connected to the charging device 6. As a result, the third electromagnetic switch 53 is configured to switch between electrical connection and disconnection between the power conditioner 7 and the charging device 6 in accordance with a control command from the controller 10 (see FIG. 1). The third electromagnetic switch 53 corresponds to the "third switch" according to the present disclosure.

[0054] The charging device 6 is configured to be connected to the vehicle 4 via a charging cable (not shown) (the charging cable may also serve as a power supply cable). The charging device 6 includes an AC / DC conversion device, and is configured to charge the vehicle 4 with AC power from the power conditioner 7 when the vehicle 4 is connected. In this example, the power supply device 3 and the charging device 6 correspond to the "power conversion device" according to the present disclosure.

[0055] The power conditioner 7 receives DC power from the solar power generation device 8 and converts it into AC power. The power conditioner 7 outputs the AC power to the earth leakage breaker 1 and also outputs it to the charging device 6 via the third electromagnetic switch 53.

[0056] The configuration of power supply system 201 other than third electromagnetic switch 53, charging device 6, power conditioner 7, and solar power generation device 8 is similar to the corresponding configuration of power supply systems 101 and 102, and therefore detailed description thereof will not be repeated.

[0057] Fig. 5 is a circuit block diagram showing a second example of the configuration of the power supply system according to embodiment 2. Power supply system 202 shown in Fig. 5 differs from power supply system 201 (see Fig. 4) in that it includes a bidirectional power conversion device 9 instead of power supply device 3 and charging device 6 (in other words, power supply device 3 and charging device 6 are integrated into one).

[0058] Fig. 6 is a circuit block diagram showing a third example of the configuration of the power supply system according to embodiment 2. Power supply system 203 shown in Fig. 6 differs from power supply system 201 (see Fig. 4) in that a first end of third electromagnetic switch 53 is electrically connected to earth leakage breaker 1 (electrical circuit PL2 for AC 200V) instead of power conditioner 7. In Fig. 6, a bidirectional power conversion device 9 may be provided instead of power feeding device 3 and charging device 6.

[0059] Fig. 7 is a circuit block diagram showing a fourth example of the configuration of the power supply system according to the second embodiment. The power supply system 204 shown in Fig. 7 differs from the power supply system 202 (see Fig. 5) in the following two points. The first difference is that the bidirectional power conversion device 9 is electrically connected to the earth leakage breaker 1 (electrical circuit PL2 for AC 200V). The second difference is that the power supply system 204 does not include the third electromagnetic switch 53, and the bidirectional power conversion device 9 can switch between power supply and charging of the vehicle 4.

[0060] Other configurations of the power supply systems 202 to 204 shown in FIGS. 5 to 7 are similar to the corresponding configurations of the power supply system 201 shown in FIG. 4, and therefore detailed description thereof will not be repeated.

[0061] <Processing flow> Fig. 8 is a flowchart showing a second example of a processing procedure for controlling the electromagnetic switches. Here, the explanation will be given using the power supply system 201 shown in Fig. 4 as an example. At the start of a series of processes, it is assumed that the first electromagnetic switch 51 is turned on, the second electromagnetic switch 52 is turned off, and the third electromagnetic switch 53 is turned off.

[0062] In S200, the controller 10 determines whether the power supply device 3 and the charging device 6 are connected to the vehicle 4. If the power supply device 3 and the charging device 6 are connected to the vehicle 4 (YES in S200), the controller 10 proceeds to S201. If the power supply device 3 and the charging device 6 are not connected to the vehicle 4 (NO in S200), the controller 10 ends the processing. Note that the processing of S200 may be omitted.

[0063] In S201, the controller 10 acquires information about the power generated by the solar power generation device 8 and also acquires information about the power consumption (load power) of each load in the house 101A. The controller 10 determines whether the amount of power generated (power generation amount) within a specified time is greater than the amount of load power (load amount) within the same specified time. If the amount of power generation is greater than the load amount (YES in S201), the controller 10 proceeds to S202.

[0064] In S202, the controller 10 determines whether the amount of power generated by the solar power generation device 8 is greater than a predetermined amount. The predetermined amount is set to an amount of power sufficient to charge the vehicle 4. If the amount of power generated by the solar power generation device 8 is greater than the predetermined amount (YES in S202), the controller 10 proceeds to S203.

[0065] In S203, the controller 10 determines whether the SOC of the vehicle 4 is higher than a required value. As described above, the required value may be set to a value corresponding to the amount of power required for the vehicle 4 to travel the next day. If the SOC is higher than the required value (YES in S203), that is, if the amount of power generated by the solar power generation device 8 is sufficient to charge the vehicle 4 but the amount of power required for travel has already been stored in the vehicle 4, the controller 10 turns on the first electromagnetic switch 51, turns off the second electromagnetic switch 52, and turns off the third electromagnetic switch 53 (S204). At this time, neither power is supplied from nor charged to the vehicle 4. The load 123 is supplied with AC power from the grid power supply 900 or power generated by the solar power generation device 8 (power after AC conversion).

[0066] If the SOC is equal to or lower than the required value (NO in S203), that is, if the amount of power generated by the solar power generation device 8 is sufficient to charge the vehicle 4 but the amount of power stored in the vehicle 4 is insufficient, the controller 10 turns on the first electromagnetic switch 51, turns off the second electromagnetic switch 52, and turns on the third electromagnetic switch 53 (S205). At this time, the vehicle 4 is charged with the power generated by the solar power generation device 8. The load 123 is supplied with AC power from the grid power supply 900 or the power generated by the solar power generation device 8.

[0067] Returning to S202, if the amount of power generated by the solar power generation device 8 is equal to or less than the predetermined amount (NO in S202), that is, if the amount of power generated is greater than the load amount but is not sufficient to charge the vehicle 4, the controller 10 turns on the first electromagnetic switch 51, turns off the second electromagnetic switch 52, and turns off the third electromagnetic switch 53 (S206). At this time, neither power is supplied from nor charged to the vehicle 4. The load 123 is supplied with AC power from the system power supply 900 or power generated by the solar power generation device 8.

[0068] Returning to S201, if the amount of power generated by the solar power generation device 8 is equal to or less than the load amount (NO in S201), that is, if the power demand of the house 101A cannot be met by the solar power generation device 8 alone, the controller 10 proceeds to S207. In S207, the controller 10 determines whether the SOC of the vehicle 4 is higher than a required value. The required value may be the same as the required value in S203, or may be a different value.

[0069] If the SOC is higher than the required value (YES in S207), that is, if there is a surplus of electric power stored in the vehicle 4, the controller 10 proceeds to S208. If the SOC is higher than the required value (NO in S207), the controller 10 proceeds to S212.

[0070] In S208, the controller 10 acquires information on the electricity price when the vehicle 4 was previously charged, for example, from an energy management server (not shown). Then, in S209, the controller 10 calculates the difference between the current electricity price and the electricity price when the vehicle 4 was previously charged, the information of which was acquired in S208, and determines whether the difference is equal to or greater than a threshold value α. If the difference is greater than the threshold value α (YES in S209), the controller 10 proceeds to S210. If the difference is equal to or less than the threshold value α (NO in S209), the controller 10 proceeds to S214. Note that in S209, the same processing as in S106 of FIG. 3 is performed, and therefore a detailed description thereof will be omitted.

[0071] In S210, the controller 10 determines whether the measurement value (current value) measured by the ammeter 130 is equal to or less than the threshold value β. If the measurement value of the ammeter 130 is equal to or less than the threshold value β (YES in S210), the controller 10 proceeds to S211. If the measurement value of the ammeter 130 exceeds the threshold value β (NO in S210), the controller 10 proceeds to S214.

[0072] The controller 10 turns off the first electromagnetic switch 51, turns on the second electromagnetic switch 52, and turns off the third electromagnetic switch 53 (S211). That is, power is supplied to the load 123 from the vehicle 4 instead of from the system power supply 900.

[0073] If the SOC is equal to or lower than the required value (NO in S207), that is, if the amount of power stored in the vehicle 4 is not enough to supply power to the outside, the controller 10 determines whether there is a charge command for the vehicle 4 (S212).

[0074] If there is a charge command (YES in S212), the controller 10 turns on the first electromagnetic switch 51, turns off the second electromagnetic switch 52, and turns on the third electromagnetic switch 53 (S213). At this time, the vehicle 4 is charged with the power generated by the solar power generation device 8. The load 123 is supplied with AC power from the system power supply 900 or the power generated by the solar power generation device 8.

[0075] If there is no charge command (NO in S212), the controller 10 turns on the first electromagnetic switch 51, turns off the second electromagnetic switch 52, and turns off the third electromagnetic switch 53 (S214). At this time, neither power supply from the vehicle 4 nor charging to the vehicle 4 is performed.

[0076] Fig. 9 is a flowchart showing a third example of the processing procedure for controlling the electromagnetic switches. Here, the explanation will be given using the power supply system 201 shown in Fig. 4 as an example. At the start of the series of processing, it is assumed that the first electromagnetic switch 51 is turned on, the second electromagnetic switch 52 is turned off, and the third electromagnetic switch 53 is turned off.

[0077] In S300, the controller 10 determines whether the power supply device 3 and the charging device 6 are connected to the vehicle 4. If the power supply device 3 and the charging device 6 are connected to the vehicle 4 (YES in S300), the controller 10 proceeds to S301. If the power supply device 3 and the charging device 6 are not connected to the vehicle 4 (NO in S300), the controller 10 ends the processing. Note that the processing of S300 may be omitted.

[0078] In S301, the controller 10 determines whether or not there is a power supply command. If there is a power supply command (YES in S301), the controller 10 proceeds to S302. If there is no power supply command (NO in S301), the controller 10 proceeds to S307.

[0079] In S302, the controller 10 acquires information on the electricity price when the vehicle 4 was last charged, for example, from an energy management server (not shown). Then, in S303, the controller 10 calculates the difference between the current electricity price and the electricity price when the vehicle 4 was last charged, the information of which was acquired in S302, and determines whether the difference is equal to or greater than a threshold value α. If the difference is greater than the threshold value α (YES in S303), the controller 10 proceeds to S304. If the difference is equal to or less than the threshold value α (NO in S303), the controller 10 proceeds to S307. Note that in S303, the same process as S106 in FIG. 3 is performed, and therefore a detailed description thereof will be omitted.

[0080] In S304, the controller 10 determines whether the measurement value (current value) measured by the ammeter 130 is equal to or less than the threshold value β. If the measurement value of the ammeter 130 is equal to or less than the threshold value β (YES in S304), the controller 10 proceeds to S305. If the measurement value of the ammeter 130 exceeds the threshold value β (NO in S304), the controller 10 proceeds to S307.

[0081] In S305, the controller 10 turns off the first electromagnetic switch 51, turns on the second electromagnetic switch 52, and turns off the third electromagnetic switch 53. Then, the controller 10 controls the power feeding device 3 to start feeding power from the vehicle 4 (S306).

[0082] In S307, the controller 10 determines whether or not a charge command has been issued. If a charge command has been issued (YES in S307), the controller 10 proceeds to S308, where it turns on the first electromagnetic switch 51, turns off the second electromagnetic switch 52, and turns on the third electromagnetic switch 53. Then, the controller 10 controls the charging device 6 to start charging the vehicle 4 (S309). The load 123 is supplied with AC power from the system power supply 900 or power generated by the solar power generation device 8.

[0083] If there is neither a power supply command nor a charging command (NO in S307), the controller 10 proceeds to S310, turns on the first electromagnetic switch 51, turns off the second electromagnetic switch 52, and turns off the third electromagnetic switch 53. In this case, neither power supply from the vehicle 4 nor charging to the vehicle 4 is performed. The load 123 is supplied with AC power from the system power supply 900 or power generated by the solar power generation device 8.

[0084] 8 and 9, the third electromagnetic switch 53 is described as being turned on or off. Even in a system configuration that does not include the third electromagnetic switch 53 as shown in Fig. 7, a person skilled in the art would understand that the same function can be achieved by switching between charging and power supply using the bidirectional power conversion device 9.

[0085] As described above, in the second embodiment, similarly to the first embodiment, the power supply systems 201 to 204 include the first electromagnetic switch 51 and the second electromagnetic switch 52. This allows power from the vehicle 4 to be supplied to the load with a simple system configuration that requires only the addition of two electromagnetic switches. In addition, in the second embodiment, the power supply systems 201 to 203 include the third electromagnetic switch 53. This allows the vehicle 4 to be charged with power generated by the solar power generation device 8 in addition to power supplied from the vehicle 4 with a simple system configuration that requires only the addition of a third electromagnetic switch.

[0086] In the above embodiment, an example in which the power supply system is provided with a ground fault circuit interrupter has been described, but the present disclosure is not limited to this. Instead of the ground fault circuit interrupter, an overcurrent circuit interrupter that electrically disconnects the system power supply 900 from the electric circuits PL1, PL2 when an overcurrent occurs (when an overcurrent is detected), or a ground fault circuit interrupter with an overcurrent circuit interrupter that electrically disconnects the system power supply 900 from the electric circuits PL1, PL2 when an overcurrent occurs or when a ground fault occurs (when a ground fault is detected) may be provided.

[0087] In the above embodiment, an example has been described in which the power supply device 3 and the bidirectional power conversion device 9 supply power to the load 123 connected to the AC 100V electrical circuit PL1, but the present disclosure is not limited to this. A power supply device or a bidirectional power conversion device may be provided that supplies power from the vehicle 4 to a load connected to the AC 200V electrical circuit PL2. The power supply device and the bidirectional power conversion device correspond to the "power conversion device" in the present disclosure.

[0088] In the above embodiment, an example has been shown in which the first electromagnetic switch 51 is electrically connected to the earth leakage breaker 113 and the overcurrent breaker 113, but the present disclosure is not limited to this. As shown in Fig. 10 , a first end of the first electromagnetic switch 51 may be electrically connected to the overcurrent breaker 113, and a second end of the first electromagnetic switch 51 may be electrically connected to the load 123. In this case, a first end of the second electromagnetic switch 52 is electrically connected to the overcurrent breaker 113 and the load 123. Note that while Fig. 10 shows a modification of the power supply system 101 of Fig. 1, the power supply systems 102, 201, 202, 203, and 204 may also be similarly modified.

[0089] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0090] 1 earth leakage breaker, 111 to 113, 211, 212 overcurrent breaker, 121 to 123, 221, 222 load, 3 power supply device, 4 vehicle, 51 first electromagnetic switch, 52 second electromagnetic switch, 53 third electromagnetic switch, 6 charging device, 7 power conditioner, 8 solar power generation device, 9 bidirectional power conversion device, 10 controller, 11 processor, 12 memory, 101, 102, 201, 202, 203, 204 power supply system, 101A house, 130 ammeter (measuring instrument), 900 system power supply, PL1, PL2 circuit.

Claims

1. A power supply system that supplies AC power from a power grid to a power load in a house, a current breaker that receives AC power from the power system to the house and breaks the power in at least one of a ground fault and an overcurrent; a load breaker configured to electrically interrupt the current breaker and the power load; a power conversion device configured to supply AC power from a vehicle to the power load when the vehicle is connected; a first switch configured to be able to switch between electrical connection and disconnection between the current breaker and the load breaker; a second switch configured to be able to switch between electrical connection and disconnection between the first switch and the power conversion device and to be able to switch between electrical connection and disconnection between the load breaker and the power conversion device; a measuring instrument that measures at least one of a current value, a voltage value, and a power value between the load breaker and the power load, a power supply system that closes the first switch and opens the second switch when the vehicle is connected to the power conversion device and the measurement value measured by the meter exceeds a threshold value;

2. The house includes a power conditioner that receives power generated by a solar power generation device, the power conversion device is configured to charge the vehicle with AC power from the power conditioner when the vehicle is connected; Further, a third switch configured to be able to switch between electrical connection and disconnection between the power conditioner and the power conversion device is provided, 2. The power supply system according to claim 1, wherein when the vehicle is connected to the power conversion device and the measurement value exceeds the threshold, the first switch is closed, the second switch is opened, and the third switch is opened.

3. the power conversion device is further configured to charge the vehicle with AC power from the current breaker when the vehicle is connected; Further, a third switch configured to be able to switch between electrical connection and interruption between the current breaker and the power conversion device is provided, 2. The power supply system according to claim 1, wherein when the vehicle is connected to the power conversion device and the measurement value exceeds the threshold, the first switch is closed, the second switch is opened, and the third switch is opened.

4. The power supply system according to any one of claims 1 to 3, wherein when the vehicle is connected to the power conversion device, the measurement value is equal to or less than the threshold value, and the current electricity price is higher than the electricity price when the power currently being charged to the vehicle is charged, the first switch is opened and the second switch is closed.

5. 4. The power supply system according to claim 1, wherein, when the vehicle is connected to the power conversion device, the first switch is open, and the second switch is closed, and the measurement value measured by the measuring instrument exceeds the threshold value, the first switch is closed and the second switch is opened.

6. 4. The power supply system according to claim 1, wherein, when the vehicle is connected to the power conversion device, the first switch is closed, and the second switch is open, if the measurement value measured by the measuring instrument exceeds the threshold value, the first switch is maintained in an open state and the second switch is maintained in a closed state.

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