JP7077970B2 - Power supply system - Google Patents

Description

The present invention relates to a power feeding system.

In the charging power control system disclosed in Patent Document 1, in an environment where a plurality of chargers operate at the same time as electrical equipment other than the charger, a plurality of chargers are used within the range of the remaining allowable power excluding the power used by the other electrical equipment. Efficiently charge with the charger. Therefore, the power consumption by the electric equipment other than the charger is measured, and the power consumption by each charger is measured. Then, the allocated power to the charger is determined based on the power consumption by the other charger and the electric equipment other than the charger and the conversion efficiency of the AC / DC conversion unit, and the charger notifies the allocated power. In response, the charging current to be supplied to the connected secondary battery is determined within the range that does not exceed the allocated power.

WO2012 / 118184

By the way, in the case of controlling the electric power of the charger for charging the electric vehicle so as not to exceed the contract electric power, it is necessary to establish a specific calculation method of the charged electric power indicated value.
An object of the present invention is to provide a power supply system capable of calculating a charge power instruction value within a range not exceeding the contract power.

The power supply system for solving the above problems includes an electric energy acquisition unit that acquires the electric energy supplied from the electric energy system, and a plurality of electric energy units for charging a vehicle connected to the electric energy system and equipped with a storage battery. A power supply system including the charger and a device other than the plurality of chargers connected to the power system, the charging controller having a charging controller for controlling the charging power for the plurality of chargers. Calculates the allocated electric energy per control unit time from the control unit time that divides the unit time for the contracted electric energy per unit time, and also the integrated electric energy amount per control unit time by the electric energy acquisition unit and the plurality. From the total charge electric energy per control unit time to the charger, the electric energy per control unit time to a plurality of devices other than the charger is calculated, and further, the allotted electric energy per control unit time and the plurality of The total chargeable electric energy per control unit time is calculated from the electric energy per control unit time for devices other than the charger, and based on the total chargeable electric energy, the plurality of chargers in the control unit time from the present time. The gist is to determine the indicated value of charging power to.

According to this, the allocated power amount per control unit time is calculated from the control unit time that divides the unit time for the contract power per unit time. The integrated power amount per control unit time by the electric energy acquisition unit and the total charge power amount per unit time for controlling multiple chargers are calculated as the power amount per control unit time for devices other than multiple chargers. .. Further, the total rechargeable electric energy per control unit time is calculated from the allocated electric energy per control unit time and the electric energy per control unit time for devices other than a plurality of chargers, and is based on the total rechargeable electric energy. From the present time, the charging power indicated values for the plurality of chargers in the control unit time are determined. Therefore, it is possible to calculate the charge power instruction value within the range that does not exceed the contract power.

Further, in the power supply system, the charging controller calculates an error power amount per control unit time from the allocated power amount per control unit time and the integrated power amount per control unit time, and determines the total rechargeable power amount. It is preferable to add the error power amount at the time of calculation and reset the added error power amount when the unit time elapses for the contract power per unit time.

Further, in the power supply system, the charging controller may set a predetermined set value as the initial total rechargeable electric energy after the reset or the total rechargeable electric energy immediately before the reset.

According to the present invention, it is possible to calculate a charge power indicated value within a range that does not exceed the contract power.

Block diagram showing a power supply system. The flowchart for demonstrating the operation of 1st Embodiment. The figure which shows the transition of electric power. The figure which shows the transition of electric power. The flowchart for demonstrating the operation of the 2nd Embodiment. The figure which shows the transition of electric power. The figure which shows the transition of electric power. The figure which shows the transition of the integrated electric energy reading value and the charger electric energy within the range of the contract electric energy.

(First Embodiment)
Hereinafter, an embodiment embodying the present invention will be described with reference to the drawings.
As shown in FIG. 1, in the present embodiment, a charging stand capable of charging a plurality of electric forklifts (vehicles indicated by reference numerals 60 and 70 in the figure) is assumed in the factory. The power supply system 10 has a plurality of chargers 30 and 31 and a plurality of devices 40 other than the chargers. The charger 30 is connected to the electric power system and is for charging the vehicle 60 equipped with the storage battery 61. The charger 31 is connected to the electric power system and is for charging the vehicle 70 equipped with the storage battery 71. The device 40 other than the plurality of chargers is connected to the power system.

The electric power of the power system is sent to the plurality of chargers 30 and 31 and the plurality of devices 40 other than the chargers via the relay device 21. The relay device 21 includes a cubicle and a distribution board. The relay device 21 and the plurality of chargers 30 and 31 are connected by a power supply line L10, and the electric power of the power system is sent to the plurality of chargers 30 and 31 via the power supply line L10 to charge the storage battery of the vehicle. Will be done. Further, the relay device 21 and the device 40 other than the plurality of chargers are connected by the power supply line L11, and the power of the power system is sent to the device 40 other than the plurality of chargers via the power supply line L11, and a plurality of devices other than the charger are sent. It is used to drive a device 40 other than a charger.

The electric energy meter 20 of the electric power company measures the amount of electric power sent from the electric power system to the relay device 21.
The power supply system 10 includes an electric energy measuring device 22 and a charging controller 50 that controls charging power for a plurality of chargers 30 and 31. The measurement result of the integrated electric energy is sent from the watt-hour meter 20 to the electric energy measuring device 22 by a pulse. The electric energy measuring device 22 as the electric energy acquisition unit measures the electric energy Pk supplied from the electric power system, that is, the integrated electric energy (system) Pk.

The electric energy measuring device 22 sends the electric energy Pk per unit time to the charging controller 50. The contract power information is sent to the charging controller 50, and the charging controller 50 acquires the contract power (amount) Pc.

The charging controller 50 and the chargers 30 and 31 are communicably connected by a communication line L20. Charging power information is sent from the chargers 30 and 31 to the charging controller 50 via the communication line L20, and the charging controller 50 acquires the charging power information from the chargers 30 and 31. The charging controller 50 sends a charging power instruction value to each of the chargers 30 and 31 via the communication line L20. For example, when the device 40 other than the plurality of chargers requires a large amount of electric power, the charging electric power by the plurality of chargers 30 and 31 is reduced so as not to exceed the contracted electric power. Each of the chargers 30 and 31 charges the storage battery of the vehicle according to the charge power instruction value from the charge controller 50.

Next, the operation will be described.
In FIG. 3, the horizontal axis represents time and the vertical axis represents electric energy. On the horizontal axis of FIG. 3, -Tc before the control unit time Tc with respect to the present and the present, -2Tc before the control unit time Tc twice with respect to the present, and before the control unit time Tc three times with respect to the present. -3Tc and Tc after the control unit time Tc with respect to the present. On the vertical axis of FIG. 3, the allocated power amount per control unit time is represented by Pct, and the power amount per control unit time to the devices 40 other than the plurality of chargers is represented by Pot. Further, the total charge power amount per control unit time for the plurality of chargers 30 and 31 is represented by Pjt, the total chargeable power amount per control unit time is represented by Pjat, and the control unit time by the power amount measuring device 22 is represented. The integrated electric energy (system) of is represented by Pkt.

The charging controller 50 executes the process shown in FIG. In the present embodiment, as shown in FIG. 4, the contract power Pc per unit time Tpc is, for example, 3000 kWh / 60 minutes. In the present embodiment, the control unit time Tc for dividing the unit time Tpc is, for example, 1 minute. That is, for example, with respect to the contract power Pc per unit time Tpc, the control unit time Tc divides the unit time Tpc into 60.

As shown in FIG. 2, in step S100, the charging controller 50 has a contract power Pc per unit time, an integrated power amount (system) Pk, and a total charge power amount per control unit time for a plurality of chargers 30 and 31. Get Pjt.

As shown in FIG. 2, in step S101, as shown in FIG. 3, the charging controller 50 allocates per control unit time from the control unit time Tc that divides the unit time Tpc for the contract power Pc per unit time Tpc. Calculate the electric energy Pct. Specifically, it is calculated by Pct = Pc / (60 × Tc). That is, it is assumed that 3000 kWh in FIG. 4 can be evenly divided and 50 kWh per minute, which is the control unit time Tc, can be consumed. This is the ideal power usage line L100 in FIG. The Tc value is exemplified for 1 minute, but may be 0.5 minutes, 2 minutes, or the like.

As shown in FIG. 3, in step S102 of FIG. 2, the charging controller 50 has an integrated electric energy Pkt per control unit time by the electric energy measuring device 22 and the total amount per control unit time for the plurality of chargers 30 and 31. From the charging electric energy Pjt, the electric energy Pot per control unit time for the devices 40 other than the plurality of chargers is calculated. Specifically, it is calculated by Pot = Pkt-Pjt. The Pjt value is the total electric energy (total charge electric energy) to the plurality of chargers 30 and 31.

As shown in FIG. 3, in step S103, the charging controller 50 has an allocated electric energy Pct per control unit time and an electric energy Pot per control unit time for devices 40 other than the plurality of chargers. Calculate the total chargeable electric energy Pjat. Specifically, it is calculated by Pjat = Pct-Pot.

In step S104 of FIG. 2, the charging controller 50 has a plurality of chargeable power reading values in the control unit time from the present time in order to give charge power instruction values to the chargers 30 and 31 based on the total chargeable electric energy Pjat per control unit time. The charge power instruction value for the chargers 30 and 31 is determined. That is, the total rechargeable electric energy before the control unit time Tc is set as the total rechargeable electric energy of the control unit time Tc.

The initial value of the total chargeable electric energy Pjat per control unit time is a fixed value.
In the comparative example shown in FIG. 4, when a fixed charge allocation amount is provided and the charge amount has a constant limiter function, the amount of power used for charging is small over time while keeping the contract power. .. On the other hand, as shown in FIG. 4, in the first embodiment, the power supplied for charging can be increased with time while not exceeding the contract power.

Conventionally, when the contract power is not exceeded by controlling the power of the charger for charging the electric vehicle, it is necessary to establish a specific calculation method of the charge power indicated value. Further, as shown in FIG. 8, the integrated power measured by the electric energy meter 20 is the total of the electric power used by the device 40 other than the charger and the electric power used by the chargers 30 and 31, and the integrated electric energy amount. Since the amount of power of the charger is included in this, it is necessary to know the available power. In the present embodiment, the Pjat value can be calculated even if the integrated electric power includes the charger electric energy, and the electric power to be used for charging, which is the available electric power, can be grasped.

In step S105 of FIG. 2, the charging controller 50 outputs the charging power indicated value to the plurality of chargers 30 and 31. According to this instruction, each of the chargers 30 and 31 charges the vehicle equipped with the storage battery by, for example, Pjat / 2 minutes per vehicle. That is, charging is performed within the range of the charge power indicated value.

According to the first embodiment, the following effects can be obtained.
(1) As a configuration of the power supply system 10, a power quantity measuring device 22 as a power quantity acquisition unit for acquiring the power quantity supplied from the power system, and a vehicle 60 connected to the power system and equipped with storage batteries 61 and 71, It has a plurality of chargers 30 and 31 for charging the 70, and a plurality of devices other than the charger 40 connected to the power system. It has a charging controller 50 that controls charging power for a plurality of chargers 30 and 31. The charging controller 50 calculates the allocated electric energy Pct (= Pc / 60 × Tc) per control unit time from the control unit time Tc that divides the unit time Tpc for the contract power Pc per unit time Tpc. The charging controller 50 charges a plurality of charge from the integrated electric energy Pkt per control unit time by the electric energy measuring device 22 as the electric energy acquisition unit and the total charge electric energy Pjt per control unit time to the plurality of chargers 30 and 31. The electric energy Pot (= Pkt-Pjt) per control unit time for the device 40 other than the device is calculated. The charging controller 50 has an allotted electric energy Pct per control unit time and a total rechargeable electric energy Pjat (= Pct-Pot) from the electric energy Pot per control unit time to the devices 40 other than the plurality of chargers. ) Is calculated. Then, the charging controller 50 determines the charging power instruction values for the plurality of chargers 30 and 31 in the control unit time from the present time based on the total chargeable electric energy Pjat. Therefore, it is possible to calculate the charge power instruction value within the range that does not exceed the contract power.

(Second embodiment)
Next, the second embodiment will be described focusing on the differences from the first embodiment.
In the second embodiment, the following functions are added as compared with the first embodiment.

In the present embodiment, as shown in FIG. 6, the difference between the instructed total charge power amount and the actually used total charge power amount is defined as the error power amount Pgt, and the error power amount Pgt in the next Tc (for example, 1 minute). Indicate the total charge power amount by adding (adding). By effectively utilizing this error power amount, that is, the surplus power, it becomes possible to approach the ideal power usage line L100 as shown in FIG. 4 in the second embodiment.

Instead of FIG. 1, the process of FIG. 5 is executed. In FIG. 5, the processing of steps S100, S101, S102, and S103 is the same as the processing of steps S100, S101, S102, and S103 of FIG. In the present embodiment, if there is an error electric energy Pgt (see FIG. 7), it is added (added) at the time of the next calculation of the total rechargeable electric energy.

As shown in FIG. 5, in step S200, as shown in FIG. 6, the charging controller 50 has an error power per control unit time from the allocated power amount Pct per control unit time and the integrated power amount Pkt per control unit time. Calculate the amount Pgt. Specifically, it is calculated by Pgt = Pct-Pkt. Then, in step S201 of FIG. 5, the charging controller 50 adds the error electric energy Pgt when calculating the total chargeable electric energy Pjat per control unit time. That is, if there is an error power amount Pgt, it is added at the time of the next calculation of the total rechargeable power amount.

Therefore, as shown in FIG. 6, the total chargeable electric energy Pjagt obtained by adding the error electric energy is a plurality of sums of the allocated electric energy Pct per control unit time and the error electric energy Pgt per control unit time. It is obtained by subtracting the electric energy Pot per control unit time for the device 40 other than the charger (Pjagt = Pct + Pgt-Poc).

Similarly, as shown in FIG. 7, the error power amount Pgt is added. Then, the charging controller 50 determines in step S202 of FIG. 5 whether or not the unit time Tpc for the contracted power per unit time has elapsed. The charging controller 50 resets the error power amount Pgt added in step S203 when the unit time Tpc for the contract power per unit time elapses. At this time, the charging controller 50 sets a preset value (fixed value) as the initial total rechargeable electric energy Pjat after the reset or the total rechargeable electric energy immediately before the reset.

In step S104 of FIG. 5, the charging controller 50 has a control unit time from the present time in order to give a charge power instruction value to each of the chargers 30 and 31 based on the total chargeable electric energy Pjat (Pjagt) per control unit time. The charging power instruction value for the plurality of chargers 30 and 31 in the above is determined. In step S105 of FIG. 5, the charging controller 50 outputs the charging power indicated value to the plurality of chargers 30 and 31. According to this instruction, the plurality of chargers 30 and 31 charge the vehicles 60 and 70 equipped with the storage batteries 61 and 71. That is, charging is performed within the range of the charge power indicated value.

As a result, as shown in FIG. 4, in the first embodiment, the electric power used for charging with time while not exceeding the contracted electric power tends to be different from the ideal electric power use line L100, but the second one. In the embodiment, by determining the total rechargeable electric power Pjat (Pjagt) in consideration of the error electric energy Pgt, the electric power supplied for charging can be increased with time while not exceeding the contracted electric power.

According to the second embodiment, the following effects can be obtained in addition to the above-mentioned effect (1).
(2) The charging controller 50 calculates the error power amount Pgt (= Pct-Pkt) per control unit time from the allocated power amount Pct per control unit time and the integrated power amount Pkt per control unit time, and can be fully charged. The error electric energy Pgt is added at the time of calculating the electric energy Pjat, and the error electric energy added when the unit time Tpc for the contract electric energy Pc per unit time Tpc elapses is reset. Therefore, it is possible to calculate the charging power instruction value within the range not exceeding the contract power so as to be closer to the contract power.

(3) The charging controller 50 is practical because it sets a preset value as the initial total rechargeable electric energy Pjat after the reset or the total rechargeable electric energy immediately before the reset.

The embodiment is not limited to the above, and may be embodied as follows, for example.
○ The electric energy of the electric energy system is acquired from the electric energy meter by using the electric energy measuring device 22 as the electric energy acquisition unit for acquiring the electric energy supplied from the electric energy system. The electric energy may be acquired by calculating the acquired instantaneous power.

○ There may be multiple chargers, and the number does not matter.
○ The vehicle equipped with the storage battery may be an electric industrial vehicle other than an electric forklift, or an electric vehicle (passenger car) other than the industrial vehicle.

10 ... Power supply system, 22 ... Electric energy measuring device, 30, 31 ... Charger, 40 ... Equipment other than multiple chargers, 50 ... Charging controller, 60 ... Vehicle, 61 ... Storage battery, 70 ... Vehicle, 71 ... Storage battery, Pc ... Contract power per unit time, Pct ... Control power allocation per unit time, Pjt ... Control to multiple chargers Total charge power amount per unit time, Pot ... Control to devices other than multiple chargers Electric energy per unit time, Pjat ... Total rechargeable electric energy per control unit time, Pgt ... Error electric energy per control unit time, Pk ... Integrated electric energy per control unit time, Tc ... Control unit time, Tpc ... Unit time.

Claims (3)

The electric energy acquisition unit that acquires the amount of electric power supplied from the electric power system,
A plurality of chargers connected to the power system to charge a vehicle equipped with a storage battery, and
With devices other than the plurality of chargers connected to the power system,
Is a power supply system with
It has a charging controller that controls the charging power for the plurality of chargers.
The charging controller is
The allocated electric energy per control unit time is calculated from the control unit time that divides the unit time for the contracted electric energy per unit time, and the integrated electric energy amount per control unit time by the electric energy acquisition unit and the plurality of chargings are performed. The amount of power per control unit time for devices other than a plurality of chargers is calculated from the total amount of charge power per control unit time for the device, and further, the amount of power allocated per control unit time and the plurality of chargers. The total rechargeable electric energy per control unit time is calculated from the electric energy per control unit time to devices other than the device, and based on the total rechargeable electric energy, the plurality of chargers in the control unit time from the present time are used. A power supply system characterized in determining a charge power instruction value. The charging controller is
The error power amount per control unit time is calculated from the allocated power amount per control unit time and the integrated power amount per control unit time, and the error power amount is added at the time of calculating the total rechargeable power amount. The power supply system according to claim 1, wherein the added error electric energy is reset when the unit time elapses with respect to the contracted electric power per unit time. The charging controller is
The power supply system according to claim 2, wherein a predetermined set value or a total rechargeable electric energy immediately before the reset is set as the initial total rechargeable electric energy after the reset.

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