JP7445511B2 - vehicle charging system - Google Patents

Description

The present invention relates to a vehicle charging system that can charge multiple vehicles at the same time.

There are vehicle charging systems that can charge a plurality of vehicles equipped with storage batteries, such as EVs (Electric Vehicles) and PHVs (Plug-in Hybrid Vehicles).
For example, in Patent Document 1, while managing power so as not to exceed the contracted power with the power supply company, in order to improve convenience for users, a relatively large current is applied to vehicles that require a large amount of charging. The charging time was controlled to avoid excessively long charging times.

Japanese Patent Application Publication No. 2013-162555

In the conventional charging system described above, priority is set according to the battery capacity of the vehicle, so the vehicle that requires more charging power is given a higher priority and can be charged with a larger current, allowing the charging of multiple vehicles. This is effective when charging is performed at the same time, and efficient charging was achieved.

However, since the vehicle that started charging later was also charged under the same conditions as the vehicle that started charging earlier, the charging time to reach full charge may be longer. Considering the amount of charge, if the battery is charged to about 20% of the storage battery capacity, for example, it is possible to drive a certain distance, such as returning home, so it is hard to imagine that it will hinder the drive. Therefore, even if it takes a long time to reach full charge, it would be more convenient for the user if the charging time to reach the amount of charge that allows the vehicle to travel a predetermined distance could be shortened.

On the other hand, there is a desire from operators of charging stations equipped with solar power generation equipment to use the surplus solar power they have been selling to charge vehicles.
However, when supplying surplus solar power to a vehicle charging system that simultaneously charges storage batteries of multiple electric vehicles, it has been difficult to supply the surplus power without waste. The reason for this is that control for allocating charging power to a plurality of storage batteries (vehicles) requires mutual communication with the vehicle, which takes time. Because control takes time, it has been difficult to properly supply solar power, which tends to fluctuate, to vehicles.

Therefore, in view of these problems, the present invention provides a vehicle charging system that can allocate surplus solar power in addition to commercial power to vehicle charging, and can perform stable distribution of the surplus at that time. It is intended to.

In order to solve the above problem, the invention of claim 1 includes a plurality of chargers for charging a vehicle and a charging control section that controls the charging current of the charger, and the invention includes commercial power and solar power generation power. In this vehicle charging system, solar power is supplied to a load different from the charger, and when surplus power is generated, it is provided to charge the vehicle via the charger. The charging control unit consists of a charging control master unit that manages surplus commercial power and solar power generation power, and a plurality of charging control units that are installed in each charger and that control the current supplied to the vehicle by the connected charger. The charging control master unit has a surplus power monitoring unit that monitors surplus power of solar power generation, and when surplus power occurs, it notifies each charging control slave unit of surplus power information all at once. On the other hand, upon receiving notification of surplus power information from the charging control master unit, the charging control slave unit displays the current charging amount, the threshold value which is the required charging amount set at the start of charging, and the surplus power information. The present invention is characterized by having a handset current control section that calculates an increase in charging current by a predetermined calculation based on and performs current increase control.
According to this configuration, since the vehicle is charged using surplus solar power, the solar power can be effectively utilized. Further, since the distribution of the surplus to each vehicle is determined by taking threshold information into consideration, the time required to reach the required charging amount set at the start of charging can be shortened, which is convenient for users.
In addition, since the distribution of surplus power is determined by the individual charging control slave unit for each vehicle, the amount of calculation by the charging control master unit can be reduced, and stable distribution without waste can be implemented in response to fluctuations in solar power generation. .

The invention according to claim 2 is the configuration according to claim 1, in which the charging control master device obtains the storage battery remaining amount information and electricity consumption information of the vehicle to be charged through the charging control slave device and the charger. and a master unit current control unit that controls the received power demand value so that it does not exceed a set reference value. In addition, the system calculates the amount of electricity that will enable each vehicle to travel a predetermined distance, sets a threshold value for the amount of charge required until the calculated amount of electricity is reached, and charges vehicles that have not reached the threshold. , the current control is performed to give priority to charging of a vehicle that has reached a threshold value.
According to this configuration, when charging a vehicle using commercial power, a threshold value for the amount of charging is set based on the amount of power that enables the vehicle to travel a predetermined distance, regardless of the type of vehicle or the remaining amount of storage battery in the vehicle, and when this threshold value is reached. Since charging of vehicles that are not available is given priority over charging of vehicles that have reached the threshold value, the time required to reach the threshold value can be shortened, which is convenient for users. Furthermore, since the mileage of vehicles whose charging amount has reached the threshold value can be approximately equal regardless of the type of vehicle, it is possible to provide equal support to users. Since demand control is also implemented, increases in electricity rates can be prevented.
Note that the electricity cost is the electricity consumption rate, and is expressed as the number of kilometers traveled per 1 kWh of electricity.

The invention according to claim 3 is characterized in that, in the configuration according to claim 2, the child device current control section obtains the threshold value information from the charging control parent device.
According to this configuration, in addition to commercial power, the distribution of surplus solar power generation power is also determined based on threshold information that allows the vehicle to travel a predetermined distance. You can definitely shorten the time.

According to the present invention, since the vehicle is charged using surplus solar power, the solar power can be effectively utilized. Further, since the distribution of the surplus to each vehicle is determined by taking threshold information into consideration, the time required to reach the required charging amount set at the start of charging can be shortened, which is convenient for users.
In addition, since the distribution of surplus power is determined by the individual charging control slave unit for each vehicle, the amount of calculation by the charging control master unit can be reduced, and stable distribution without waste can be implemented in response to fluctuations in solar power generation. .

1 is a configuration diagram showing an example of a vehicle charging system according to the present invention. It is a flowchart which shows the flow of a threshold value setting. It is a flowchart which shows the flow of allocating priorities. It is a flowchart which shows the flow of charging control. It is a flowchart which shows the flow of control of a charge control main unit when using solar power generation power for vehicle charging. It is a flowchart which shows the flow of control of a charging control slave device when using solar power generation power for vehicle charging.

Hereinafter, embodiments embodying the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an example of a vehicle charging system according to the present invention. In FIG. 1, 2 is a charging control master unit (hereinafter simply referred to as "master unit"), and 3 is a charging control slave unit (hereinafter simply referred to as "slave unit"). It consists of
The slave unit 3 is installed for each charger 4 to which the vehicle 5 is connected, the slave unit 3 and the charger 4 are connected via a signal line L1, and the base unit 2 and the slave unit 3 are connected via a signal line L2. and communicate with each other.

On the other hand, in addition to the commercial power P, a solar power generation facility 8 is connected to the power receiving equipment 7 that supplies power to the load 9 and the charger 4, and the commercial power P supplied at high voltage is transferred to the power receiving equipment 7 at a low voltage. and is supplied to the load 9 and charger 4 via power cables L3 and L4, respectively.
Note that the power generated by the solar power generation equipment 8 is mainly supplied to the load 9, and when a surplus of generated power occurs, it is supplied to the charger 4 under control described below. Moreover, although the base unit 2 and each slave unit 3 are connected by the signal line L2, the signal line L2 may be omitted and they may communicate with each other wirelessly.

The main unit 2 includes a first measurement unit 21 that obtains received power information from the smart meter 10 installed on the commercial power P lead-in line L5, and a first measurement unit 21 that detects surplus solar power from reverse power flow to the commercial power system. A second measuring section 22, a storage section 23 that stores demand values, reference values (described later), threshold values, calculation formulas, etc., and a communication section 25 (first communication section 25a, second communication section 25b, etc.) that communicates with each child device 3. - An n-th communication unit 25n), a main unit CPU 26 that determines the charging current of the charger 4 and controls each part of the main unit 2, and the like.

In addition to the function of communicating with the slave device 3, the communication unit 25 has a function of communicating with the vehicle 5 connected to the charger 4 via the slave device 3, and under the control of the parent device CPU26, the communication unit 25 has a function of communicating with the vehicle 5 connected to the charger 4 via the slave device 3. Information on the remaining capacity (kWh) of the storage battery installed in the 5 and electricity consumption (number of kilometers traveled per 1 kWh of electricity) is available.
Through the function of the communication unit 25, the main unit CPU 26 calculates a threshold value necessary for charging control based on the storage battery remaining amount information and electricity consumption information acquired from the vehicle 5.

The handset 3 includes a first handset communication unit 31 that communicates with the base unit 2, a second handset communication unit 32 that communicates with the charger 4, and a handset memory that stores an arithmetic expression for calculating an increase in charging current, etc. 33, a slave unit CPU 34 that controls the connected charger 4 and the slave unit 3, and the like.
The child device CPU 34 receives the surplus power information of the solar power generation notified from the parent device 2 and controls the charging current of the charger 4 . Further, information on the amount of charge (ascertained from the charging current and charging time) supplied to the vehicle by the charger 4 is transmitted to the base unit 2 .

The vehicle charging system configured as described above operates as follows. FIG. 2 is a flowchart of threshold setting, which will be explained with reference to FIG.
When the main unit CPU 26 acquires the storage battery remaining amount and power consumption information from the vehicle 5 via the charging control slave unit 3 and the charger 4 (S11), the main unit CPU 26 determines the amount of electric power that enables traveling a predetermined distance based on the acquired information. is calculated, and the required charging amount is calculated based on the storage battery remaining amount information (S12).
The amount of charge required to enable traveling a predetermined distance is calculated by the following formula.
Required charging amount (kWh) = Predetermined traveling distance (km) / Electricity cost (km/kWh) - Remaining battery capacity (kWh) ... (Formula 1)

The required charging amount thus calculated is set as a threshold value (S13).
In this way, the threshold value is the amount of charge required to travel a predetermined distance, regardless of the type of vehicle.
Note that the predetermined distance is set as a distance (for example, 50 km) that can be traveled to the home or the next charging station.

Once the threshold value is set, charging priorities are assigned next, and charging control for each vehicle 5 is then performed. Priority allocation is performed as follows.
FIG. 3 is a flowchart showing the flow of assigning priorities, which will be explained with reference to FIG. The main unit CPU 26 starts charging when the vehicle 5 is connected to the charger 4 (the charging plug of the vehicle 5 is connected) and the threshold value is set. At the same time, priorities are assigned together with other vehicles 5 for which charging control is already being performed.

First, the number of vehicles 5 whose charging amount is less than the threshold value (unachieved number: n) is ascertained (S21), and then the number of vehicles 5 whose charging amount is equal to or higher than the threshold value (achieved number: m) is ascertained (S21). S22).
Note that the main device CPU 26 obtains and understands the charging amount information after starting charging of each vehicle 5 from the child device 3, and compares this value with a threshold value to make a determination.

Next, the vehicles 5 included in the unachieved number n are arranged in descending order of charge amount, ranked from 1st to nth, and allocated (S23), and the vehicles 5 included in the achieved number m are further arranged in order of charge amount. They are arranged, ranked and allocated from n+1st to n+mth (S24). In this way, the order is established from the first to n+m.
At this time, among the 1st to nth vehicles 5, the first vehicle 5 has the highest amount of charge, the nth vehicle 5 has the least amount of charge, and among the n+1 to n+mth vehicles 5, the n+1th vehicle 5 has the highest amount of charge. The amount of charge is the largest, and the amount of charge of the (n+m)th vehicle 5 is the smallest. Once the priorities are assigned in this way, we proceed to control the increase/decrease of the current.

FIG. 4 shows a flowchart showing the flow of current increase/decrease control for each ordered vehicle 5, and charging control will be explained with reference to this flow. This control is also performed by the base unit 2, and the control changes greatly depending on whether the current received power is relative to the reference value.
Note that the reference value is a power value that is, for example, 10% smaller than the maximum demand value, and indicates a numerical value set by the consumer in order to reduce the maximum demand value and reduce the contract fee.

Hereinafter, a case will be described in which the criterion for determining deviation information is a reference value. After receiving the priority allocation (S31) information, first, if the deviation information is equal to 0 (proceed to the left in S32), that is, if the current received power is approximately equal to the reference value, the charging current of any vehicle 5 is The process ends without making any changes, and returns to the first step S31, where priorities are assigned. Note that the current received power is the value of the received power that the first measurement unit 21 obtains from the smart meter 10.
However, the deviation information is a value defined as in Equation 2 of the following equation.
Deviation information (kW) = Current received power (kW) - Standard value (kW) ... (Formula 2)

Next, if the deviation information is a positive value (proceeds downward in S32), that is, if the received power exceeds the reference value, control is performed to reduce the current. To be more precise, if it is determined that there is a possibility that the average power for 30 minutes will exceed the reference value by calculating and predicting the average power for 30 minutes from the current received power, control is performed to reduce the current.
Specifically, the exceeding current value (deviation value) is calculated using the following formula 3 (S33), and charging current reduction control (S34) is performed in order from vehicle 5 that has reached the threshold value and has the least amount of charge. .
Deviation value = Deviation information (kW) / Voltage (V) ... (Formula 3)

However, the maximum reduction amount per vehicle is the smaller of the current current value minus a predetermined minimum current value or the calculated deviation value (S35). For example, if the deviation value is 10 amperes and the value obtained by subtracting the predetermined minimum current value from the current current value is 5 amperes, 5 amperes is selected and the charging current of the n+mth vehicle 5 with the highest charging amount is Control is implemented to reduce the current by 5 amperes. In this way, the vehicle 5 with the least amount of charge among those that have reached the threshold becomes the highest priority target for charging current reduction. In other words, charging has the lowest priority.

Then, the current value obtained by subtracting the reduced current value from the deviation value is set as a new deviation value (S36), and the steps from S34 to S37 are repeated until the deviation value becomes 0 or for all the vehicles 5 to be charged, Control is performed in the set order of vehicles. In this way, the newly set charging current value is notified from the communication unit 25 to each charger 3 via the handset 3 (S43), and the control from S31 to S43 is repeated at predetermined time intervals such as 1 second. It will be implemented according to the following.
As a result, when reducing the received power from the commercial power P, the charging current is reduced from the vehicle 5 that has reached the threshold value. At this time, the charging current is reduced starting from the vehicle 5 that has the least amount of charge. Therefore, the amount of charge of the vehicle 5 that starts charging later does not exceed the amount of charge of the vehicle 5 that starts charging first, and the user who takes a long time to charge does not become dissatisfied.

On the other hand, when the deviation information is negative, that is, when the received power has not reached the reference value, control is performed to increase the charging current.
Specifically, the current value that can be increased (margin value) is calculated using the following equation 4 (S38), and the charging current is increased in order from the vehicle 5 with the highest charging amount to the vehicle 5 with the lowest charging amount among the vehicles 5 that do not meet the threshold value. (S39).
Margin value = - Deviation information (kW) / Voltage (V) ... (Formula 4)

However, the maximum amount of increase per vehicle is the smaller of the value obtained by subtracting the current current value from the predetermined charging maximum current value or the calculated margin value (S40). For example, if the value obtained by subtracting the current current value from the maximum charging current value is 5 amperes and the margin value is 10 amperes, 5 amperes is selected and the charging current of the first vehicle 5 with the lowest charging amount is set to 5 amperes. Control to increase amperage is implemented. In this way, the vehicle 5 with the largest amount of charge among the vehicles 5 that have not reached the threshold becomes the highest priority target for increasing the charging current, and the current is increased.

Then, the current value obtained by subtracting the increased current value from the margin value is set as a new margin value (S41), and the steps from S39 to S42 are repeated until the margin value becomes 0 or for all the vehicles 5 to be charged. , the vehicle is controlled in the set order. In this way, the newly set charging current value is notified to each charger 4 (S43), and charging is controlled.

In this way, when charging a vehicle using commercial power, a threshold value for the amount of charging is set based on the amount of power that enables the vehicle to travel a predetermined distance, regardless of the type of vehicle or the remaining battery level of the vehicle 5. Since the charging of the vehicle 5 is prioritized over the charging of the vehicle 5 that has reached the threshold value, the time until the threshold value is reached can be shortened, which is convenient for the user. Further, since the mileage of the vehicle 5 whose charging amount has reached the threshold value can be approximately equal regardless of the vehicle type, it is possible to treat users equally. Since demand control is also implemented, increases in electricity rates can be prevented.

In addition, when reducing the received power from the commercial power P, the charging current is reduced from the vehicle 5 that has reached the threshold value, and when increasing the received power from the commercial power P, the charging current is reduced from the vehicle 5 whose charging amount is below the threshold value. 5, the charging current is increased.

Next, a description will be given of vehicle charging control when a surplus of solar power generation occurs while the vehicle is being charged using commercial power.
FIG. 5 is a flowchart showing the flow of control of the base unit 2 when solar power generation power is used for vehicle charging, and FIG. 6 is a flowchart showing the control flow of the slave unit 3 when using solar power generation power for vehicle charging. This flowchart will be described with reference to this flow.
The second measuring unit 22 detects the reverse power flow to the commercial power system, that is, the power selling (S51), and when the power selling occurs (Yes in S52), the main unit CPU 26 detects the power selling from the second measuring unit 22. The value is acquired (S52), and an increase in the charging current to the vehicle 5 at which this electricity selling current becomes 0 is calculated (S53).
This increase in charging current is calculated by the following equation 5.
Current increase value = (power selling current value / system margin) / number of operating chargers ... (Formula 5)
The calculated current increase value is notified all at once to all slave units 3 in operation (S54). Notification of the current increase value is carried out at regular time intervals, and if no power selling has occurred, "0" is notified (S55).

Note that the system margin is an adjustment value when there are points to be noted depending on the system, and although "1" is theoretically desirable, it is set, for example, to 0.8, depending on the installation environment of the system. Further, information on the number of chargers 4 in operation is acquired from the slave unit 3. Further, the power supplied from the power receiving equipment 7 to the charger 4 is AC power with a constant voltage such as 200V, and the current increase value is also a power increase value of the same ratio.

On the other hand, each slave unit 3 receives notification of the current increase value from the base unit 2 (S61), and if the increase value is not 0, the slave unit 3 is in charge (connected to the slave unit 3). The allocated amount of charger 4 is calculated (Yes in S62). The controlled charging current including the allocated amount is calculated using the following equation 6 based on the notified current increase value (S63). If the notified current increase value is 0, there is no increase in charging current (No in S62).
Charging current after control (A) = Charging current value before control (A) + Increased value of charging current × (1 + (Charging amount (Wh) / Threshold value (Wh))) × Coefficient (Formula 6)
Note that the "coefficient" is a coefficient for calculating the amount of current that increases the charging current to the minimum value regardless of the charging priority, and is, for example, 0.5. 2. In addition, the "charging amount" is the charging power amount calculated by the handset 3 from the charging current and charging time of the charger 4 as described above, and the "charging amount/threshold value" is the amount of charging power that has been calculated by the handset 3 from the charging current and charging time of the charger 4. If it becomes 0, the priority is lowered to 0.
Handset 3 controls charger 4 to charge with the current value calculated in this way (S64).

In this way, the surplus solar power is used to charge the vehicle, so the solar power can be effectively utilized. In addition, the distribution of surplus power to individual vehicles 5 is calculated based on the amount of charge up to now, the threshold value that is the required amount of charge set at the start of charging, and the notified surplus power information, so charging starts. The time it takes to reach the amount of charge required to travel a predetermined distance can be shortened, which is convenient for the user.
Furthermore, the allocation of surplus power is calculated and determined by each charging control slave unit 3 for each vehicle 5, so the amount of calculation by the charging control master unit 2 can be reduced. It is possible to carry out stable distribution without any problems.

1. Vehicle charging system, 2. Charging control master device, 3. Charging control slave device, 4. Charger, 5. Vehicle, 7. Power receiving equipment, 8. Solar power generation equipment, 9. - Load, 10... Smart meter, 10... Smart meter (watt hour meter), 21... First measuring section, 22... Second measuring section (surplus power monitoring section), 23... Storage section, 25... - Communication section (charged vehicle information acquisition section, notification section), 26.. Master unit CPU (master unit current control section), 33.. Handset CPU (handset current control section), P.. Commercial power.

Claims (3)

A vehicle charging system that includes a plurality of chargers for charging a vehicle and a charging control unit that controls the charging current of the charger, and that charges the vehicle using commercial power and solar power generation power,
The photovoltaic power is supplied to a load different from the charger, and if surplus power occurs in the generated power, it is provided to charge the vehicle via the charger,
The charging control unit includes a charging control master unit that manages surplus commercial power and solar power generation power;
a plurality of charging control slave units installed for each of the chargers to control the current supplied to the vehicle by the charger to which it is connected;
The charging control master unit includes a surplus power monitoring unit that monitors the surplus power of solar power generation power;
and a notification unit that simultaneously notifies each charging control slave device of surplus power information when the surplus power is generated;
Upon receiving the notification of the surplus power information from the charging control master device, the charging control slave device determines the amount of charge to date, the threshold value that is the required amount of charge set at the start of charging, and the surplus power information. A vehicle charging system comprising: a slave current control section that calculates an increase in charging current by a predetermined calculation and performs current increase control. The charging control master unit includes a charging vehicle information obtaining unit that obtains storage battery remaining amount information and electricity consumption information of the vehicle to be charged via the charging control slave unit and the charger;
A main unit current control unit that controls the demand value of the received power so that it does not exceed a set reference value,
The main unit current control unit calculates the amount of electric power that enables each vehicle to travel a predetermined distance based on the information obtained by the charging vehicle information acquisition unit, and
A charging amount required until the calculated amount of electric power is reached is set as the threshold value, and current control is performed to prioritize charging of a vehicle that has not reached the threshold value over charging of a vehicle that has reached the threshold value. The vehicle charging system according to claim 1. 3. The vehicle charging system according to claim 2, wherein the child device current control unit obtains the threshold information from the charging control parent device.

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