WO2019097582A1 - Dc power supply system - Google Patents

Abstract

The present invention addresses the problem of effectively utilizing power generation in a natural energy power generation device without suppressing the power generation. Each time rechargeable electric power Wc and weather forecast information Dwf are acquired, a power management device 9 calculates, for the next cycle, an expected recharging electric power Wcp for a storage battery 11, a predicted generated electric power Wgf in a power generation device 3b, and predicted load electric powers Wlfa, Wlfb in load devices 71a, 71b, and compares the electric power sum Wsm of the electric powers Wlfa, Wlfb, Wcp with the predicted generated electric power Wgf. When it is determined that the predicted generated electric power Wgf is greater than the electric power sum Wsm, the power management device 9 operates a bidirectional DC/DC converter 14 in the current cycle to supply the storage battery 11 with electric power equal to the expected recharging electric power Wcp, and operates DC/DC converters 5a, 5b in the current cycle to supply the load devices 71a, 71b with electric power equal to the predicted load electric powers Wlfa, Wlfb, and supply a load device 71c in a stopped state with electric power equal to the difference between the predicted generated electric power Wgf and the electric power sum Wsm.

Description

DC power supply system

The present invention relates to a stand-alone DC power supply system not connected to a commercial power supply.

As a direct current feed system of this type, a direct current feed system disclosed in Patent Document 1 below is known. The DC power feeding system includes a natural energy power generation device, a load device having a regulation load and operating with generated power from the natural energy power generation device, and a storage battery connected to the natural energy power generation device and the load device to perform charging and discharging. A stand-alone power supply system including a power storage device, wherein the stand-alone power supply system calculates demand forecast data of a load device and generation output forecast data of a natural energy power plant using the weather forecast data, and the demand When it is predicted by the prediction data and the power generation output prediction data that the storage battery is charged beyond the maximum charging power of the storage battery, the power generation output from the natural energy power generation device is suppressed.

According to this independent power supply system, when it is predicted that the storage battery is charged by exceeding the maximum charge power of the storage battery by the demand forecast data and the power generation output forecast data, the power generation output from the solar power generation apparatus is Since the control is performed, it is possible to control so as not to exceed the maximum charging power of the storage battery.

WO 2013/128731 (page 2, 13; Figure 1)

However, in the above-described conventional direct current feeding system, when it is predicted that the storage battery is charged beyond the maximum charging power of the storage battery, the direct current supply system is configured to suppress the power generation output from the natural energy power generation apparatus. In the feed system, there is a problem to be solved that the suppressed power of the generated power that can be originally generated in the natural energy power generation apparatus is wasted.

This invention is made in view of the said subject, and an object of this invention is to provide the direct current | flow electric power feeding system which can be effectively utilized, without suppressing the electric power generation in a natural energy electric power generating apparatus.

In order to achieve the above object, in the direct current feed system according to the present invention, a direct current bus serving as a bus bar for direct current feed, a power generating device generating power based on natural energy, and the generated power of the power generating device is supplied to the DC bus. It is connected between the first converter, the storage battery, the storage battery, and the DC bus, and the generated power supplied to the DC bus and the charging power of the storage battery are bi-directionally converted to power, Bi-directional converter for supplying power from the DC bus to the storage battery or from the storage battery to the DC bus, and voltage converting DC power of at least one of the generated power and the charging power supplied to the DC bus A second converter for supplying the load equipment, a power generation log including a weather condition and generated power when the power generation apparatus is operated, and the load equipment is operated Control unit which acquires a load log including the current weather condition and load power, and sequentially acquires the chargeable power of the storage battery and the weather prediction information at a predetermined acquisition time, the control unit Charge power calculation processing for calculating, based on the chargeable power and the weather forecast information, scheduled charge power for the storage battery in a period until the acquisition time that arrives next, each time the chargeable power and the weather forecast information are acquired; Generated power prediction processing for calculating predicted power generation of the power generation apparatus in the period based on the power generation log and the weather prediction information; predicted load power on the load device in the period is the load log and the weather prediction information Load power prediction processing calculated based on the total power of the predicted load power and the planned charging power and The electric power comparison process of comparing with the predicted generated power is executed, and when it is determined in the electric power comparison process that the predicted generated power is larger than the total power, the storage battery is sent to the storage battery with respect to the bidirectional converter in the period. Charging / discharging control processing for supplying power for scheduled charging power; and supplying the predicted load power to the load device for which the predicted load power of the load devices has been calculated by the second converter, A load device control process is performed to supply the difference power between the predicted generated power and the total power to the load device in a stopped state among the load devices.

According to the present invention, when the predicted generated power is larger than the total power, surplus power (difference power between the predicted generated power and the total power) generated in the predicted generated power is supplied to the load device which is normally in a stopped state. Because the power generation apparatus operates based on natural energy, the power generated by the power generation apparatus can be effectively used without suppressing the power generation of the power generation apparatus.

ADVANTAGE OF THE INVENTION According to this invention, it can utilize effectively, without suppressing the electric power generation in a natural energy electric power generating apparatus.

FIG. 1 is a block diagram of a DC power supply system 1; FIG. 10 is an explanatory diagram for describing first to fourth processing contents of charge / discharge control processing and load device control processing. FIG. 6 is an explanatory diagram for explaining an operation of the DC power supply system 1; FIG. 7 is another explanatory view for explaining the operation of the direct current feed system 1;

Hereinafter, an embodiment of a direct current feed system will be described with reference to the attached drawings. The direct current feed system is not limited to the following embodiments. Further, the components described below include those which can be easily conceived by those skilled in the art, and substantially the same components, and the components can be appropriately combined.

First, the configuration of the direct current feed system 1 as a direct current feed system will be described.

The DC power supply system 1 includes a DC bus 2 and one or more power generation devices 3 (in this example, three power generation devices 3a, 3b, 3c as an example, hereinafter referred to as "power generation device 3" when not distinguished) The first converter 4 (three power conditioners 4a, 4b and 4c described later as an example in this example) disposed corresponding to the three, and one or more load devices 71 (one or more load devices connected to the DC feeding system 1) In this example, three load devices 71a, 71b, 71c as an example (hereinafter also referred to as "load device 71" when not distinguished), a second converter 5 (in this example, three examples described later as an example) second converter 5a, 5b, 5c. hereinafter, when no distinction is also referred to as "second converter 5"), a plurality of direct-current power supply 6 (DC power supply units _{61 and} 62 2, ..., 6 ), Third converter 7, and includes a power management apparatus 9 generates a DC voltage based on the power generated by the power generator 3, a stand-alone can be supplied to the load device 71 DC power supply system (commercial power supply ( It is configured as a DC power supply system not connected to a commercial AC power supply).

The DC bus 2 is laid over the installation place of the power generation device 3, the installation place of each DC power supply 6, and the installation place of the load device 71, and functions as a bus bar of DC power supply. Further, DC bus 2 has a predetermined voltage including a nominal bus voltage as a result of control of charge / discharge operation of bidirectional DC / DC converter 14 in a plurality of DC power supply devices 6 described later by power management device 9. The bus voltage Vbs is defined within a range (for example, within a voltage range of DC 350 V or more and DC 400 V or less including DC 370 V as a nominal bus voltage).

The power generation device 3 is configured of a distributed power supply device. In this case, the distributed power supply unit is configured of a power generation unit using natural renewable energy such as a solar power generation unit, a wind power generation unit, or a hydroelectric generation unit, or an engine type power generation unit using fossil energy such as light oil and gasoline. It is possible. In this example, for easy understanding, as one example, it is configured by one engine type power generation device 3a and power generation devices 3b and 3c using natural regenerated energy.

The power generation device 3a is started and stopped by an operation (manually) by the operator, and generates and outputs an AC voltage V1 of a predetermined voltage value in an operation state. The power management apparatus 9 can also control start / stop. In addition, the power generation device 3a is included in the plurality of DC power supply devices 6, such as at the time of the first startup of the DC power supply system 1, and at the time of restart after the DC power supply system 1 stops for a long time. When a large amount of charging power is temporarily required to charge the storage battery 11, the storage battery 11 is operated only for a predetermined period. Therefore, as an example in the present embodiment, the power generation device 3a is required for the load device 71 (two in the present embodiment, as an example, the load devices 71a and 71b) in each cycle T described later included in the fixed period. It is assumed that it is possible to generate sufficient power (predetermined known generated power Wgap) capable of charging the storage battery 11 while supplying various load powers. Further, for example, by adopting a configuration such as outputting to the power management device 9 a state signal indicating that the power generation device 3a is in operation in the operating state, the power management device 9 can detect the operation / stop of the power generation device 3a. Is configured.

In addition, the power generation device 3b is configured of a solar power generation device as an example, and automatically generates generated power Wgbp (generated power in each cycle T) that changes according to the sunshine condition in the daytime, and direct current The voltage V2b is generated and output. In addition, the power generation device 3c is configured of a pumped storage hydroelectric power generation device as one example, and is controlled by the power management device 9 to execute one of the storage operation, the power generation operation, and the operation stop. In this case, in the storage operation, the power generation device 3c performs an operation of pumping water from the lower pond to the upper pond dam by operating a pumping pump as a load device 71c described later, and in the power generation operation, the upper pond dam The water is dropped from the lower reservoir to the lower reservoir and the generator is operated to generate and output a DC voltage V2c.

The first converter 4 is composed of three power conditioners 4a, 4b, 4c arranged corresponding to the two power generation devices 3a, 3b, 3c in this example. In the present embodiment, as an example, power conditioner 4a is configured to include an AC / DC converter, and is disposed corresponding to power generation device 3a. The power conditioner 4a operates with the DC voltage internally generated based on the AC voltage V1, and is controlled by the power management device 9 to generate the AC voltage V1 as the generated power output from the power generation device 3a as a bus. The voltage is converted into a voltage Vbs and supplied to the DC bus 2.

Power conditioners 4b and 4c are configured to include, for example, a DC / DC converter, and are arranged corresponding to power generation devices 3b and 3c. The power conditioner 4b operates with the DC voltage generated internally based on the DC voltage V2b, and is controlled by the power management device 9 to control the power generation operation of the corresponding power generation device 3b to generate generated power. While being configured to be controllable, the DC voltage V2b as the generated power output from the power generation device 3b is converted into the bus voltage Vbs and supplied to the DC bus 2. Further, the power conditioner 4c operates with the DC voltage internally generated based on the DC voltage V2c, converts the DC voltage V2c as the generated power output from the power generation device 3c into the bus voltage Vbs, Supply to 2.

The second converter 5 is configured of, for example, a DC / DC converter that operates with a DC voltage generated internally based on the bus voltage Vbs. In this example, for easy understanding, it is assumed that the load devices 71 (DC loads) connected to the DC power feeding system 1 are three load devices 71a, 71b and 71c, and the second converter 5 is a load The second converter 5a (also referred to as DC / DC converter 5a) corresponding to the device 71a, the second converter 5b (also referred to as DC / DC converter 5b) corresponding to the load device 71b, and the second converter 5c corresponding to the load device 71c Suppose that it is comprised by three (it is also called DC / DC converter 5c). In this case, the DC / DC converter 5a is controlled by the power management device 9 to convert the bus voltage Vbs into a load voltage VLa which is a DC voltage used by the load device 71a (DC voltage conversion). Supply to The DC / DC converter 5a also has a current limiting function of limiting the load current supplied from the DC bus 2 to the load device 71a with the upper limit current value set from the power management unit 9.

Similar to the DC / DC converter 5a, the DC / DC converters 5b and 5c are controlled by the power management device 9, respectively, and the bus voltage Vbs is a load voltage which is a DC voltage used by the corresponding load devices 71b and 71c. The voltage is converted into each of VLb and VLc (DC voltage conversion), and is supplied to the load devices 71b and 71c. Further, the DC / DC converters 5b and 5c have a current limiting function of limiting the load current supplied from the DC bus 2 to the load devices 71b and 71c with the upper limit current value set from the power management unit 9. .

The load devices 71a, 71b, 71c are DC loads that operate by receiving the load voltages VLa, VLb, VLc (hereinafter, also referred to as load voltage VL unless otherwise specified), which are DC voltages, The load devices 71a and 71b include lighting devices operating with direct current voltage, household appliances such as a television and a refrigerator operating with direct current voltage, and information devices such as a personal computer and a portable terminal operating with direct current voltage. In addition, the load device 71c is configured by a pumping pump (an electric pump constituting a part of the power generation device 3c) for pumped storage power generation that operates with a direct current voltage. In addition, the load device 71 c is configured to be on / off controllable by the power management device 9. The load device 71 c is not limited to the pumping pump for the pumped storage power generation, and various devices (for example, direct current) may be used as long as the power management device 9 can control ON / OFF thereof. It is possible to set it as the cooling device etc. which cool the inside of the building in which the power supply device 6 was arrange | positioned.

DC power supply device 6 includes a DC power supply device 6 _1, 6 _2, · · ·, n-number of 6 _n (n is an integer of 2 or more. Or less, particularly when no distinction is also referred to as a DC power supply device 6) is disposed There is. Each DC power supply device 6 is configured to include a storage battery 11, a battery management unit (BMU (Battery Management Unit)) 12, a contactor 13 and a bidirectional DC / DC converter 14, respectively. The storage batteries 11 ₁ , 11 ₂ ,..., 11 _n (hereinafter, also referred to as the storage battery 11 when not distinguished in particular) are formed of lithium ion batteries as an example, but are not limited thereto. It can also be configured with a hydrogen battery and a NAS battery (sodium-sulfur battery). Each storage battery 11 has a prescribed power capacity (nominal capacity), and is configured to be capable of charge operation and discharge operation within a predetermined working voltage range including a nominal voltage.

Further, although one of the storage batteries 11 (in the example, the storage battery 11 _{1 in the} example) is also used for supplying power to the DC bus 2, the BMU 12 of each of the DC power supply devices 6 ₁ to 6 _n The battery mainly functions as a storage battery for supplying power (operation voltage Vop) for the operation of the contactor 13 and the power management apparatus 9. Therefore, the storage battery 11 _1, corresponding bidirectional DC / DC converter 14 ₁ is in the operating state, and through the contactor 13 ₁ in the coupled state are connected to a bidirectional DC / DC converter 14 ₁ In the operating state, charge and discharge control is performed by power management device 9 such that charge voltage Vba is less than the upper limit value of the working voltage range and equal to or higher than the voltage threshold (predetermined voltage value) exceeding the lower limit value. .

_{BMU12 1, 12 2, ···,} 12 n ( hereinafter, especially when no distinction is also referred to as BMU12), each storage battery _{11 1,} 11 2 corresponding, ..., are respectively disposed 11 _n, later Operate with the operating voltage Vop. In addition, each BMU 12 measures the charge voltage Vba of the storage battery 11 as an example, and calculates the SOC (State of charge) by measuring the current value of the charge / discharge current of the storage battery 11 in the operating state. And the function of outputting information including the measured charging voltage Vba, the current value of the charging / discharging current, and the calculated SOC to the power management apparatus 9 as battery information. Further, when the BMU 12 receives the contactor control information from the power management apparatus 9, the BMU 12 executes the control contents indicated by the contactor control information to the contactor 13 (when the control content is a cutoff instruction, the contactor 13 shifts to the cutoff state). When the control content is a connection instruction, the contactor 13 is also brought into a connected state.

Contactor _{13 1,} 13 2, ..., 13 _n (hereinafter, when not particularly distinguished, also referred to as contactor 13), the corresponding storage battery _{11 1,} 11 2, ..., and positive and negative 11 _n, corresponding .., 14 _n are disposed between the storage batteries 11 ₁ , 11 ₂ ,..., 11 _n on the side of the storage batteries 11 ₁ , 14 ₂ ,. Operate with the operating voltage Vop. Each contactor 13 is controlled by the corresponding BMU 12 to shift to any one of the blocking state and the coupling state, and in the blocking state, the positive electrode and the negative electrode, and the pair of input / output terminals Are cut off (disconnected), and in the connected state, the positive electrode and the negative electrode are connected to the pair of input / output terminals.

The bi-directional DC / DC converters 14 ₁ , 14 ₂ ,..., 14 _n (hereinafter also referred to as bi-directional DC / DC converter 14 when not particularly distinguished) are a pair of input / output of the storage battery 11 side as described above. The terminals (one pair of input / output terminals) are connected to the storage battery 11 via the contactor 13 and the other pair of input / output terminals are connected to the DC bus 2 so that the storage battery 11 and the DC bus 2 It is connected (arranged) between. In addition, the bidirectional DC / DC converter 14 performs CV operation (constant voltage charging / discharging operation) with a DC voltage generated internally based on the bus voltage Vbs, and is operation controlled by the power management device 9. Specifically, when the control information received from power management device 9 indicates a charge instruction, bi-directional DC / DC converter 14 boosts or reduces (voltage conversion) bus voltage Vbs input from the other pair of input / output terminals. Then, the direct current constant current is supplied to the storage battery 11 for charging by performing output to the storage battery 11 from one pair of input / output terminals (charging operation is performed). Thereby, the bus voltage Vbs of the DC bus 2 is lowered. On the other hand, when the received control information is a discharge instruction, bidirectional DC / DC converter 14 boosts or lowers (converts voltage) the charging voltage Vba of storage battery 11 input from one pair of input / output terminals to set the other pair. The storage battery 11 is discharged with a DC constant current by performing output to the DC bus 2 from the input / output terminal of (a discharge operation is performed). Thus, the bus voltage Vbs of the DC bus 2 is raised. The bi-directional DC / DC converter 14 can be configured by, for example, a known bi-directional DC / DC converter disclosed in JP-A-2016-152641.

The bidirectional DC / DC converter 14 also has a current limiting function of limiting each current value of the charging current supplied to the storage battery 11 and the discharge current discharged from the storage battery 11 to the maximum current value or less of the storage battery 11.

The third converter 7 is configured of a DC / DC converter (hereinafter, also referred to as a DC / DC converter 7). Further, DC / DC converter 7, the positive electrode and the negative electrode thereof a pair of input terminals of the storage battery 11 ₁ of the DC power supply device _61, and is connected without passing through the contactor 13 _1, the charging voltage Vba of the battery 11 ₁ Operate. In addition, DC / DC converter 7 boosts or lowers (converts voltage) the charging voltage Vba of storage battery 11 in the operating state, so that BMU 12 and contactor 13 of each DC power supply device 6 and power management device 9 The operation voltage Vop to be used is generated and output.

The power management device 9 is configured by a computer operating at the operation voltage Vop and functions as a control unit. Further, the power management device 9 is a power generation log (a past log in which the weather condition when the power generation device 3b operates and the generated power at that time are associated) Drg1 for the power generation device 3b using natural regenerated energy Acquisition processing for acquiring load logs (the respective past logs in which the weather conditions when the load devices 71a, 71b operate and the load power at each time are associated with each other) for the load devices 71a, 71b (Hereafter, it is also referred to as first acquisition processing to distinguish). In addition, the power management apparatus 9 defines in advance an acquisition process (hereinafter, also referred to as a second acquisition process to distinguish) for acquiring weather prediction information Dwf for an area (area) including the installation place of the power generation device 3b. Execute at acquisition time. In this example, as an example, the acquisition time is defined as the time of arrival at a predetermined cycle T (one hour in this example) defined in advance, such as 1:00, 2:00,. Therefore, in the present example, the power management apparatus 9 executes the second acquisition process at a cycle T (for example, at an hour interval).

As an example, the power management apparatus 9 includes a communication apparatus connectable to a network such as the Internet or a local area network, executes the first acquisition processing, and generates the above power generation log Drg1 and load log from an external server via the network. Drg2 is acquired and stored, and the second acquisition processing is executed to acquire and store the above-described weather prediction information Dwf from the weather data distribution site via the network.

The weather forecast information Dwf is, for example, weather forecast data for one day starting from a cycle T arriving after the current cycle T (that is, the latest weather forecast data for one day starting from the next cycle T) Information that can predict the amount of solar radiation to the power generation device 3b (for example, information indicating whether it is daytime or nighttime (is it a solar radiation period), and information indicating weather such as sunny, cloudy, or rain And the like, and together with the predicted amount of solar radiation, includes information (such as temperature) necessary to predict the power generated by the power generation device 3b. That is, the power management apparatus 9 acquires, at a cycle T, the weather prediction information Dwf including the latest information described above. In this example, since the power generation device 3b is configured by a solar power generation device, the weather prediction information Dwf is configured to include information capable of predicting the amount of solar radiation, but the power generation device 3b is a wind power generation device. When configured, the weather prediction information Dwf is configured of information that can predict the power generated by the wind turbine generator, such as the wind volume (wind speed).

In addition, the power management apparatus 9 executes an acquisition process (hereinafter also referred to as a third acquisition process to distinguish) for acquiring the chargeable electric power Wc of each storage battery 11 at a cycle T. In the third acquisition process, the power management apparatus 9 first acquires the battery information output from each BMU 12, and then, the SOC of each storage battery 11 included in the acquired battery information and the rating of each known storage battery 11 Based on the capacity, the chargeable power Wc (= rated capacity-SOC) of each storage battery 11 is calculated and acquired. Thus, the power management apparatus 9 acquires the latest chargeable power Wc for each storage battery 11 at a cycle T.

The power management apparatus 9 executes charge power calculation processing, generated power prediction processing, load power prediction processing, and power comparison processing each time the weather prediction information Dwf and the chargeable power Wc are acquired (every cycle T).

In this case, in the charge power calculation process, the power management device 9 calculates the scheduled charge power Wcp for each storage battery 11 in the cycle T that arrives next, based on the weather prediction information Dwf and the chargeable power Wc.

Specifically, in the charging power calculation process in the stopped state of the power generation device 3a, the power management apparatus 9 first includes a solar radiation period (period from dawn to sunset) (daytime) included in the weather prediction information Dwf. It is detected whether the next period T is included in the solar radiation period based on the information on. Then, when the result of this detection is that the next cycle T is included in the solar radiation period, the power management apparatus 9 specifies a continuous period starting from the next cycle T and ending simultaneously with the end of the solar radiation period. Identified as a sunshine period.

Also, when the specific sunshine period is specified in this way, the power management apparatus 9 determines how many cycles T are included in the specific sunshine period (the number of specific sunshine periods is m (m is a positive integer)). Calculate that consists of T). The power management unit 9, the storage battery _{11 1,} 11 2, ..., chargeable power _{Wc 1,} Wc 2 of 11 _n, ..., by dividing each _{Wc n} in this number m, the specific Scheduled charge powers Wcp ₁ , Wcp ₂ ,..., Wcp _n for charging the storage batteries 11 ₁ , 11 ₂ ,..., 11 _n in each cycle T (including the next cycle T) included in the sunshine period = Calculate chargeable power Wc ₁ / m, Wc ₂ / m, ..., Wc _n / m). Below, chargeable power _{Wc 1, Wc 2, ···,} for the _{Wc n,} in particular, also referred to as a rechargeable electric power Wc when no distinction, planned charging power _{Wcp 1, Wcp 2, ···,} will also Wcp _n, particularly distinguished Also referred to as scheduled charging power Wcp when not.

The reason why the chargeable power Wc is dispersed in each cycle T included in the specific sunshine period in this manner is that the storage batteries 11 are completely filled at the end of the specific sunshine period as compared with the case where they are not dispersed. It is because the possibility that the current value of the charging current to the storage battery 11 can be made lower than the maximum current value can be increased while transitioning to the charging state. The SOCs of the respective storage batteries 111, 112, ..., 11n at the start of the specific sunshine period may differ depending on the storage battery 11 according to the respective charge / discharge states, whereby the rated capacities of the respective storage batteries 11 are the same. Even in this case, the chargeable powers Wc1, Wc2,..., Wcn may be different for each of the batteries 111, 112,. In this example, each chargeable power Wc is distributed to the same m periods T in a common specific sunshine period (divided into m), and the planned charge power Wcp (the planned charge power Wcp is the chargeable power Wc). By proportionally charging, each storage battery 11 which may have a different SOC is gradually shifted to a fully charged state in a common specific sunshine period.

Therefore, when the sunshine duration is 8 h, although the specific sunshine duration decreases by one cycle T (one hour each) like 8 h, 7 h, ..., each time one cycle T elapses, Since the SOC also increases by the scheduled charging power Wcp, the scheduled charging power Wcp for each cycle T in the sunshine period has a substantially constant value for each storage battery 11. For example, when the chargeable power Wc at the start of the sunshine period (8 h as an example) of one storage battery 11 is 16 kWh, the scheduled charge power Wcp in the first one cycle T (1 hour) is the specific sunshine period 8 h Therefore, the planned charging power Wcp in the next one cycle T (one hour) is 2 kW (= 16/8), but the specific sunshine time is 7 h, but only 2 kWh is charged, so 2 kW (= 14/7), and the planned charging power Wcp in the next one cycle T (1 hour) is 2 kW (= 12/6) because it is further charged by 2 kWh although the specific sunshine time is 6 h. The planned charging power Wcp remains constant at 2 kW until the last period T of the sunshine period.

Therefore, even if the storage battery 11 is of a specification capable of charging 5 kWh in one hour at the maximum current value, for example, a total of 16 kWh of electric power can be stored in the storage battery 11 every one hour such as 5 kWh, 5 kWh, 5 kWh, 1 kWh. The charging current of the storage battery 11 can be suppressed to less than the maximum current value as compared to the case of charging (in this case, the battery will be fully charged in the first 4 hours of the daylight hours 8h). ing.

In addition, when the power management device 9 detects that the above-described next period T is included in the solar radiation period when the power generation device 3a is in the stopped state, the result is not included in the solar radiation period. Since there is no specific sunshine period of (ie, the specific sunshine period is zero), the planned charging power Wcp in the next cycle T is calculated as zero.

On the other hand, in the charge power calculation process in each cycle T (that is, each cycle T included in the above-described fixed period for operating the power generation device 3a) in the operation state of the power generation device 3a, the power management device 9 A period starting from T and ending simultaneously with the end of this fixed period is specified as a specific charging period (continuous period). Further, the power management apparatus 9 calculates how many cycles T are included in the specific charge period (the specific charge period is composed of m periods T). The power management unit 9, the storage battery _{11 1,} 11 2, ..., chargeable power _{Wc 1,} Wc 2 of 11 _n, ..., by dividing each _{Wc n} in this number m, the specific Scheduled charging powers Wcp ₁ , Wcp ₂ ,..., Wcp _n for charging the storage batteries 11 ₁ , 11 ₂ ,..., 11 _n in each cycle T (including the next cycle T) included in the charging period = Calculate chargeable power Wc ₁ / m, Wc ₂ / m, ..., Wc _n / m). The reason why the chargeable power Wc is dispersed in each period T included in the specific charge period in this manner is the same as in the stop state of the power generation device 3a described above, as compared with the time when it is not dispersed. Because it is possible to increase the possibility that the current value of the charging current to the storage battery 11 can be made lower than the maximum current value while making each storage battery 11 shift to the full charge state just at the end of the specific charging period. is there.

Further, in the generated power prediction process, the power management device 9 predicts the predicted generated power Wgf (= generated power Wgbp) of the power generation device 3b in the next cycle T based on the power generation log Drg1 and the weather prediction information Dwf. Calculate. In this case, if the result of detecting whether the next cycle T is included in the solar radiation period in the above charging power calculation process is not included in the solar radiation period, that is, the above-mentioned specific sunshine period is If not present, the predicted generated power Wgf is calculated to be zero. However, in the generated power prediction process in the operating state of the power generation device 3a, the power management device 9 adds the known generated power Wgap in the cycle T of the power generation device 3a to the above-mentioned predicted generated power Wgf (generated power Let Wgap and Wgbp be the predicted generated power Wgf in the generated power prediction process.

Further, in the load power prediction process, the power management apparatus 9 calculates the predicted load powers Wlfa and Wlfb for the load devices 71a and 71b in the next cycle T, the load log Drg2 for the load devices 71a and 71b, and the weather prediction information Calculated based on Dwf.

Further, in the power comparison process, the power management apparatus 9 sums the predicted load power Wlf at each load device 71a, 71b (Wlfa + Wlfb) and the scheduled charge power Wcp at each storage battery 11 (Wcp ₁ + Wcp ₂ +. · Calculate the total power Wsm of + Wcp _n ) and compare the calculated predicted generated power Wgf with the total power Wsm to obtain a comparison result (determine the magnitude relationship between the predicted generated power Wgf and the total power Wsm) . Further, in the power comparison process, the power management apparatus 9 compares the sum of the predicted load power Wlf and the predicted generated power Wgf to obtain the comparison result (size of predicted load power Wlf and predicted generated power Wgf Determine the relationship).

Further, the power management device 9 executes charge / discharge control processing for each DC power supply device 6 and load device control processing for each load device 71 from the beginning of the arriving cycle T. The power management device 9 also executes a voltage measurement process of measuring the bus voltage Vbs. In this case, the power management apparatus 9 can adopt a configuration in which the bus voltage Vbs is directly measured. For example, the first converter 4 (at least one of the power conditioners 4a, 4b, 4c) A configuration in which the power management apparatus 9 indirectly measures the bus voltage Vbs via the first converter 4 may be employed so as to have a function of measuring the voltage Vbs and outputting the same to the power management apparatus 9.

Next, the operation of the DC power supply system 1 will be described. Note that the storage battery 11 _1, since they are used to power components, such as power management apparatus 9, as described above, the charging voltage Vba is less than the upper limit of the voltage range, and more voltage threshold It shall be charged beforehand so that it may become. Also, each contactor 13 is initially in the disconnected state.

In this DC power feeding system 1, for example, at the time of the first start of the DC power feeding system 1 or at the time of restarting after the long-term stop of the DC power feeding system 1, other storage batteries 11 ₂ to 11 _n excluding the storage battery 11 ₁ When it is assumed that the battery is in the overdischarged state (the state where the charging voltage Vba is lower than the lower limit value of the working voltage range), first, the generator 3a is operated for a certain period to output the AC voltage V1.

For this reason, first, the operation of the DC power feeding system 1 when operating the power generation device 3a will be described. In this case, the power conditioner 4 a operates by receiving the supply of the AC voltage V 1, converts the AC voltage V 1 into the bus voltage Vbs, and supplies the bus voltage V bs to the DC bus 2. Therefore, the bus voltage Vbs of the DC bus 2 rises within a predetermined voltage range (voltage range of DC 350 V or more and DC 400 V or less).

In the daytime, the power generation device 3b automatically generates power and outputs the DC voltage V2. Thus, the power conditioner 4b operates by receiving the supply of the DC voltage V2, converts the DC voltage V2 into the bus voltage Vbs, and supplies the bus voltage Vbs to the DC bus 2. In the present example, as described above, the generated power Wgap capable of sufficiently charging the storage battery 11 while supplying the necessary load power to the load device 71 in each cycle T included in the fixed period as the power generation device 3a. Therefore, during the power generation operation of the power generation device 3b, the power allocated to the charge of the storage battery 11 becomes too large. In this case, since the bidirectional DC / DC converter 14 of this example is configured to perform the CV operation, the charging current to the storage battery 11 will be too large, and the deterioration of the storage battery 11 will be accelerated.

In order to avoid this, when the power management device 9 detects that the power generation device 3a is in operation based on the state signal output from the power generation device 3a, the above-mentioned surplus power (in addition, the power generation device 3b The load device control process is executed to cause the load device 71c to consume the generated power generated when the power generation operation is started, thereby reducing the power allocated to the charge of the storage battery 11.

In the DC power supply system 1, DC / DC converter 7 from the storage battery 11 ₁ and is supplied with a charging voltage Vba is operated day and night, and BMU12 and contactor 13 of each DC power supply device 6, the power management apparatus 9 The operation voltage Vop is output (supplied) at the same time. Therefore, the BMU 12 and the contactor 13 of each DC power supply 6 and the power management unit 9 are in operation. Therefore, BMUs 12 ₁ to 12 _n of DC power supply devices 6 ₁ to 6 _{n in} the operating state periodically charge voltage Vba etc. for corresponding storage batteries 11 ₁ to 11 _n (for example, a cycle shorter than cycle T) Or at the same cycle as cycle T) and output to the power management unit 9 as battery information.

Further, the power management apparatus 9 in the operating state executes, for example, the first acquisition process once at the time of the first activation of the DC power feeding system 1 to acquire and store the power generation log Drg1 and the load log Drg2. In this example, as an example, since the power generation log Drg1 and the load log Drg2 are configured of past logs for one year, the configuration of the DC power feeding system 1 does not change, and the weather condition at the installation site does not change significantly. As long as it is possible, for example, the power generation log Drg1 and the load log Drg2 acquired in the first acquisition processing executed only once at the time of startup can be used continuously even after the second year. The configuration for acquiring the power generation log Drg1 and the load log Drg2 is not limited to this configuration, and for example, a predetermined period such as several weeks, several months, or a year may be (1) Acquisition processing may be executed and acquired.

Thereafter, the power management apparatus 9 defines the processing contents in the charge / discharge control processing and the load device control processing for each cycle T based on the information obtained in the immediately preceding cycle T, while the charge / discharge control processing and the load device Start an operation to execute control processing. Further, the power management apparatus 9 acquires information to acquire the above information for defining the contents of each process in the charge / discharge control process and the load device control process executed in the next coming cycle T (the next cycle T). The process is executed every cycle T.

In this information acquisition process, the power management apparatus 9 performs a second acquisition process of acquiring weather forecast information Dwf, a third acquisition process of acquiring chargeable power Wc for each storage battery 11, and the acquired chargeable power Wc. Generated power prediction processing for calculating predicted generated power Wgf of the entire power generation devices 3a and 3b based on charge power calculation processing for calculating scheduled charging power Wcp for each storage battery 11, acquired weather forecast information Dwf, power generation log Drg1, etc. Load power prediction processing for calculating the predicted load power Wlf in each load device 71a, 71b based on the acquired weather prediction information Dwf and the load log Drg2, and total power Wsm (= total of predicted load power Wlf + each storage battery 11 Of the estimated charging power Wcp at the time of comparison with the predicted generated power Wgf and the total of the predicted load power Wlf A running power comparison process for obtaining a result of comparison between the predicted power generation WGF, acquires information for specifying the processing content in executing the next cycle T charge and discharge control process and the load device control.

This information includes the cycle T in the solar radiation period together with the planned charging power Wcp in the incoming cycle T, the predicted generated power Wgf in the cycle T, and the predicted load power Wlf in the cycle T described above. Information indicating the comparison result of the predicted generated power Wgf and the total power Wsm, and the information indicating the comparison result of the sum of the predicted load power Wlf and the predicted generated power Wgf. When the power generation device 3a is in operation, the generated power Wgap of the power generation device 3a is included in the predicted generated power Wgf. Therefore, for information indicating the comparison result of the predicted generated power Wgf and the total power Wsm, The comparison shows that the predicted generated power Wgf is larger than the total power Wsm.

The processing contents in the charge / discharge control processing and the load device control processing are divided into the following four processing contents from the first processing contents to the fourth processing contents based on the respective information acquired in the immediately preceding cycle T ((4) See Figure 2). The first processing content among them is the processing content when the comparison result of the predicted generated power Wgf and the total power Wsm is the comparison result that the predicted generated power Wgf is larger than the total power Wsm, and the second processing content Is the processing content when the comparison result between the predicted generated power Wgf and the total power Wsm is the comparison result that the predicted generated power Wgf matches the total power Wsm, and the third processing content is the total with the predicted generated power Wgf The comparison result with the power Wsm is a comparison result that the predicted generated power Wgf is smaller than the total power Wsm, and the comparison result between the predicted load power Wlf and the predicted generated power Wgf is a predicted generated power Wgf The processing content in the case of the comparison result of being larger than the total of the predicted load power Wlf, and the fourth processing content is that the comparison result of the predicted generated power Wgf and the total power Wsm is the predicted generation The comparison result that the power Wgf is smaller than the total power Wsm, and the comparison result between the sum of the predicted load power Wlf and the predicted generated power Wgf is that the predicted generated power Wgf is less than or equal to the total of the predicted load power Wlf It is the processing content at the time of a comparison result.

Specifically, when the first processing content corresponds to the above, since the predicted power generation Wgf is larger than the total power Wsm, the surplus power (the predicted power generation Wgf and the total power Wsm Differential power (= predicted generated power Wgf−total power Wsm) is generated. For this reason, in this state, the power allocated to charging the storage battery 11 becomes too large (beyond the planned charging power Wcp), which causes the bi-directional DC / DC converter 14 to perform CV operation. The charging current becomes too large, which may accelerate the deterioration of the storage battery 11.

Therefore, as shown in FIG. 2, in the charge / discharge control process, the first process content is to charge the bi-directional DC / DC converter 14 by supplying the scheduled charging power Wcp to the corresponding storage battery 11 for charging. It is processing content. In this charge / discharge control process, power management device 9 charges voltage Vba of each storage battery 11 included in the battery information acquired from BMU 12 of each DC power supply device 6 in the third acquisition process (for each storage battery 11 included in the battery information While specifying DC power supply device 6 having rechargeable storage battery 11 (storage battery 11 whose charge voltage Vba has not reached the upper limit value of the working voltage range) based on SOC, identified DC power supply device 6 The contact control information indicating the connection instruction to the BMU 12 is output from the beginning to the end of the current cycle T, and the charge instruction to the bidirectional DC / DC converter 14 of the DC power supply 6 (scheduled charging power Wcp Control information indicating an instruction to average the battery over the entire cycle T and charge the storage battery 11 is output.

Further, as shown in FIG. 2, in the load device control process, the first processing content is a load voltage VLa, which is used by the corresponding load devices 71a and 71b for each DC / DC converter 5a and 5b. The processing content is to cause the load devices 71a and 71b to supply the predicted load powers Wlfa and Wlfb while converting and outputting the bus voltage Vbs so as to be VLb. Further, as described above, since surplus power (differential power (= predicted power generation Wgf−total power Wsm)) is generated in the predicted generated power Wgf, the DC / DC converter 5c is further processed in the load device control process. Control the load device 71c in the stopped state to shift the load device 71c to the operating state while converting and outputting the bus voltage Vbs to the load voltage VLc used by the corresponding load device 71c. And the above-described surplus power is supplied to the load device 71c with respect to the DC / DC converter 5c. As a result, the power supplied to each storage battery 11 (power allocated to charging the storage battery 11) can be made the scheduled charging power Wcp.

Further, when the content of the second process is satisfied, since the predicted generated power Wgf matches the total power Wsm, the above-described surplus power is not generated in the predicted generated power Wgf. Therefore, as shown in FIG. 2, in the charge / discharge control process, the second process content is to charge the bi-directional DC / DC converter 14 by supplying the scheduled charge power Wcp to the corresponding storage battery 11 for charging. It is processing content. Further, in the load device control process, the bus voltage Vbs is converted and output to the DC / DC converters 5a and 5b so that the load voltages VLa and VLb used by the corresponding load devices 71a and 71b are obtained. In addition, the processing content is that the load devices 71a and 71b are supplied with the predicted load powers Wlfa and Wlfb. Further, since no surplus power is generated in the predicted generated power Wgf, in the load device control process, the operation of converting the bus voltage Vbs and outputting the load voltage VLc to the DC / DC converter 5c is stopped and The processing content is to cause the load device 71c to maintain the stopped state.

Further, in the case where the above-described third processing content is applied, since the predicted generated power Wgf is larger than the total of the predicted load power Wlf, the predicted load power Wlfa, Wlfb can be supplied to the load devices 71a, 71b. Since the generated power Wgf is smaller than the total power Wsm, when the predicted load powers Wlfa and Wlfb are supplied to the load devices 71a and 71b, the charging power that can be supplied to each storage battery 11 is smaller than the scheduled charging power Wcp. Therefore, as shown in FIG. 2, in the load device control process, the third process content is the load voltage VLa, which is used by the corresponding load devices 71a and 71b for each DC / DC converter 5a and 5b. The processing content is to cause the load devices 71a and 71b to supply the predicted load powers Wlfa and Wlfb while converting and outputting the bus voltage Vbs so as to be VLb. Further, since the predicted generated power Wgf is smaller than the total power Wsm, the difference power of the total of the predicted generated power Wgf and the predicted load power Wlf (= the total of the predicted generated power Wgf−the predicted load power Wlf) is charged to each storage battery 11 In the case of using it, the surplus power does not occur in the predicted generated power Wgf. Therefore, in the load device control process, the operation of converting the bus voltage Vbs and outputting the load voltage VLc to the DC / DC converter 5c is stopped, and the stopped state is maintained for the load device 71c. Processing content. Further, in the charge / discharge control process, although each scheduled storage power Wcp can not be charged to each storage battery 11, predicted generated power Wgf and predicted load power Wlf for each bidirectional DC / DC converter 14 are obtained. The processing content is, for example, evenly dividing and charging each storage battery 11 of the difference power of the sum of.

Further, in the case where the above-described fourth processing content is applied, the predicted generated power Wgf is less than or equal to the total of the predicted load power Wlf, so when trying to supply the predicted load power Wlfa, Wlfb to the load devices 71a, 71b, There is no electric power that can be used to charge the storage battery 11, and when the predicted generated power Wgf is less than the total of the predicted load power Wlf, it is necessary to discharge the storage batteries 11 in reverse. Therefore, as shown in FIG. 2, in the load device control process, the fourth processing content is the load voltage VLa, which is used by the corresponding load devices 71a and 71b for each DC / DC converter 5a and 5b. The processing content is to cause the load devices 71a and 71b to supply the predicted load powers Wlfa and Wlfb while converting and outputting the bus voltage Vbs so as to be VLb. Further, since the predicted generated power Wgf is equal to or less than the total of the predicted load power Wlf, there is no surplus power for charging each storage battery 11 or operating the load device 71c. Therefore, the DC / DC converter 5c is processed to stop the operation of converting the bus voltage Vbs and outputting the load voltage VLc and causing the load device 71c to maintain the stopped state.

Further, as described above, when the predicted generated power Wgf is less than the total of the predicted load power Wlf, the total of the predicted load power Wlf can not be equaled with the predicted generated power Wgf alone. For this reason, in the above-described fourth control content, in the charge and discharge control process, the shortage of power (= sum of predicted load power Wlf−predicted generated power Wgf) generated in predicted generated power Wgf is equally applied to each storage battery 11 The processing content is to divide and discharge. In the charge / discharge control process, the power management apparatus 9 determines the charge voltage Vba of each storage battery 11 included in the battery information acquired from the BMU 12 of each DC power supply 6 in the third acquisition process (for each storage battery 11 included in the battery information While specifying the DC power supply device 6 having the rechargeable storage battery 11 (the storage battery 11 in which the charging voltage Vba has not reached the lower limit value of the working voltage range) based on the SOC, Output contact control information indicating a connection instruction to the BMU 12 from the beginning to the end of the current cycle T, and a discharge instruction to the bi-directional DC / DC converter 14 of the DC power supply 6 (scheduled charging power Wcp Control information indicating an instruction to average and discharge the storage battery 11 over the entire cycle T is output.

As described above, the information indicating the comparison result of the predicted generated power Wgf and the total power Wsm during the fixed period in which the power generation device 3a is operating is the comparison result that the predicted generated power Wgf is larger than the total power Wsm It is shown. Therefore, based on the comparison result, the power management apparatus 9 executes the charge / discharge control process and the load device control process with the first control content described above. Here, the surplus power (surplus power generated in the predicted generated power Wgf) in each period T in a fixed period during which the power generation device 3a is operating refers to the surplus power generated mainly in the generated power Wgap generated by the power generation device 3a. However, when it is predicted that the power generation device 3b is operated, the predicted power generation Wgf (= generated power Wgbp) of the power generation device 3b is added.

Therefore, the power management apparatus 9 changes the processing contents of supplying the predicted load powers Wlfa and Wlfb to the load devices 71a and 71b and shifts the load device 71c in the stopped state to the operating state and surplus power (differential power = predicted generated power The load device control process is executed with the process of supplying Wgf−total power Wsm) to the load device 71c. Thereby, since the surplus power generated in the predicted generated power Wgf can be used for the operation of the load device 71c, it is possible to effectively utilize the generated power in the power generation device 3a. Further, when the power generation device 3b is also in the power generation state, it is possible to effectively utilize the power generated by the power generation device 3b without suppressing the power generation by the power generation device 3b.

Also, as a result of this surplus power (differential power) being supplied to the load device 71c, it becomes possible to make the total power allocated to charge of each storage battery 11 equal to the sum of the respective scheduled charge powers Wcp. Therefore, the power management device 9 executes the charge / discharge control process with the process content of charging each storage battery 11 with the respective scheduled charging power Wcp.

Thus, each storage battery 11 identified as being chargeable is charged at each period T corresponding to the corresponding planned charging power Wcp, that is, charged using the entire area for a fixed period, and at the end of the fixed period It is almost fully charged. Power management device 9 determines whether or not charging voltage Vba included in the battery information output in a cycle T from BMU 12 of each DC power supply device 6 has reached the upper limit value of the operating voltage range (or included in the battery information). Of the DC power supply device 6 including the storage battery 11 when it is determined that the fully charged state has been detected while detecting whether the storage battery 11 has reached the full charge state). The contact control information indicating a shutoff instruction is output to the BMU 12, and the storage battery 11 is disconnected from the bidirectional DC / DC converter 14 by shifting the contactor 13 to the shutoff state. Thereby, overcharging of the storage battery 11 is prevented. The power management unit 9, upon charging of each battery ₁₁ 1 ~ 11 _n, which perform the charging of the battery 11 ₁ for outputting a charging voltage Vba to be used in generating operating voltage Vop preferentially. Thus, the storage battery 11 _1, the charging voltage Vba is always charged to be the upper limit vicinity of the voltage range.

In addition, in the power generation device 3c, the pumping pump, which is the load device 71c, is operated for a certain period, so that the working period of the pumping pump (that is, for a certain period) from the lower pond to the upper pond dam. It is in a state where water of a corresponding amount of water is pumped up (a state where power storage corresponding to the length of a certain period is performed).

In each cycle T, the power management apparatus 9 performs the second acquisition process, the third acquisition process, the charge power calculation process, the generated power prediction process, the load power, and the charge / discharge control process and the load device control process described above. Information for defining the control content in charge / discharge control processing and load device control processing to be executed in the next coming cycle T by executing prediction processing and power comparison processing (planned charging power Wcp in coming cycle T Information on whether or not this cycle T is included in the solar radiation period together with the predicted generated power Wgf in this cycle T, and the predicted load power Wlf in this cycle T, comparison between the predicted generated power Wgf and the total power Wsm Information indicating the result, and information indicating the comparison result of the sum of the predicted load power Wlf and the predicted generated power Wgf) is acquired.

The power generation device 3a is operated only for a fixed period and stopped. In this case, the power management device 9 detects the stop of the power generation device 3a, and shifts to the operation based on the power generated by the power generation devices 3b and 3c.

In each cycle T when the power generation apparatus 3a is not operating, the power management apparatus 9 performs the second acquisition process, the third acquisition process, the charge power calculation process, the generated power prediction process, and the load power prediction performed in the immediately preceding cycle T. Processing and information obtained by execution of the power comparison processing (the scheduled charge power Wcp in the current cycle T, the predicted generated power Wgf in this cycle T, and the predicted load power Wlf in this cycle T, this cycle T In the information on whether the solar radiation period is included, the information indicating the comparison result of the predicted generated power Wgf and the total power Wsm, and the information indicating the comparison result of the sum of the predicted load power Wlf and the predicted generated power Wgf) The control content in the charge / discharge control processing and the load device control processing is defined based on the above, and the charge / discharge control processing and the load device control processing are executed with the prescribed control content. .

Next, a specific example is given and demonstrated. Planned charging power Wcp (total of) every day (every hour in this example) in the daytime (sunshine hour) and the period (nighttime) before and after that in one day, predicted generated power Wgf and predicted load power Wlf For example, it is assumed that (sum of Wlfa and Wlfb) is calculated and predicted by the power management apparatus 9 as shown in FIG. In this case, regarding the relationship between the predicted generated power Wgf and the total power Wsm (= the predicted load power Wlf + the scheduled charging power Wcp in each storage battery 11), the power management apparatus 9 may The predicted generated power Wgf becomes less than the total power Wsm at 16 o'clock and 17 o'clock, and the predicted generated power Wgf coincides with the total power Wsm at 9 o'clock and the predicted generated power at 10 o'clock to 15 o'clock When Wgf exceeds the total power Wsm, prediction is made in a time (period T) immediately before each time (period T). Further, regarding the relationship between the predicted generated power Wgf and the predicted load power Wlf, the power management apparatus 9 makes the predicted generated power Wgf equal to or less than the predicted load power Wlf at night, for example, at 7 o'clock and 17 o'clock (for example, 7) On a hourly basis, if the predicted generated power Wgf exceeds the predicted load power Wlf from 8:00 to 16:00, the predicted generated power Wgf matches the predicted load power Wlf), and the prediction is made in the cycle T immediately before each cycle T Do.

Therefore, the power management apparatus 9 predicts the estimated generated power Wgf to be less than the total electric power Wsm and predicts the estimated generated power Wgf at the 7 o'clock and 17 o'clock stages at the 6 o'clock and 16 o'clock stages. It is predicted that the load power Wlf will be less than or equal to (the predicted generated power Wgf coincides with the predicted load power Wlf for 7 o'clock), and based on the predicted information, the fourth mentioned above for this 7 o'clock and 17 o'clock Execute charge / discharge control processing and load device control processing according to the processing content.

That is, as shown in FIG. 4, in the load device control process, power management device 9 applies load voltages VLa and VLb used by corresponding load devices 71a and 71b to DC / DC converters 5a and 5b. The predicted load powers Wlfa and Wlfb are supplied as they are to the load devices 71a and 71b while the bus voltage Vbs is converted and output as they become (the same actual load power as the predicted load powers Wlfa and Wlfb (hereinafter referred to as actual load power Wlfa , Wlfb))). Further, the power management apparatus 9 causes the DC / DC converter 5 c to stop the operation of converting the bus voltage Vbs and outputting the load voltage VLc, and causes the load device 71 c to maintain the stopped state. Execute control.

Further, in the charge and discharge control process, the power management device 9 equally divides the insufficient power (= predicted load power Wlf−predicted generated power Wgf) generated in the predicted generated power Wgf into each storage battery 11 and discharges it. At around 7 o'clock, since the predicted load power Wlf matches the predicted generated power Wgf and the above-mentioned insufficient power is zero, the discharge amount is zero. In the charge / discharge control process, the power management apparatus 9 determines the charge voltage Vba of each storage battery 11 included in the battery information acquired from the BMU 12 of each DC power supply 6 in the third acquisition process (for each storage battery 11 included in the battery information While specifying the DC power supply device 6 having the rechargeable storage battery 11 (the storage battery 11 in which the charging voltage Vba has not reached the lower limit value of the working voltage range) based on the SOC, The contact control information indicating the connection instruction is output to the BMU 12 and the control information indicating the discharge instruction is output to the bidirectional DC / DC converter 14 of the DC power supply device 6 (discharge operation is performed).

Furthermore, even if the storage battery 11 is discharged in this way, if the total of the predicted load powers Wlf can not be obtained, the power management device 9 can execute the control for the power generation device 3c to perform the power generation operation.

Further, in the power management apparatus 9, for example, at the 7 o'clock and 15 o'clock stages, the predicted generated power Wgf becomes less than the total electric power Wsm and the predicted generated power Wgf is about the 8 o'clock and 16 o'clock coming next. It is predicted that the predicted load power W1f will be exceeded, and based on the predicted information, the charge / discharge control process and the load device control process according to the third process described above are executed at 8 o'clock and 16 o'clock.

That is, as shown in FIG. 4, in the load device control process, power management device 9 applies load voltages VLa and VLb used by corresponding load devices 71a and 71b to DC / DC converters 5a and 5b. Control is performed to supply the predicted load powers Wlfa and Wlfb to the load devices 71a and 71b as they are (to supply the actual load powers Wlfa and Wlfb) while converting the bus voltage Vbs so as to be output. Further, the power management apparatus 9 causes the DC / DC converter 5 c to stop the operation of converting the bus voltage Vbs and outputting the load voltage VLc, and causes the load device 71 c to maintain the stopped state. Execute control.

In addition, although the power management device 9 is smaller than the planned charging power Wcp in the charge and discharge control processing, the power obtained by evenly dividing the differential power (= the predicted generated power Wgf-the predicted load power Wlf) into each storage battery 11 Charge it. In this charge / discharge control process, the power management device 9 outputs contact control information indicating a connection instruction to the BMU 12 of the DC power supply 6 identified as having the rechargeable storage battery 11, and the DC power supply 6. By outputting control information indicating a charging instruction to the bidirectional DC / DC converter 14, the storage battery 11 of the DC power supply device 6 is charged (a charging operation is performed).

Further, for example, at 8 o'clock, the power management apparatus 9 predicts that the predicted generated power Wgf matches the total power Wsm at the next 9 o'clock, and based on the predicted information, the 9 o'clock In the above, the charge / discharge control process and the load device control process with the second process content described above are executed.

That is, as shown in FIG. 4, in the load device control process, power management device 9 applies load voltages VLa and VLb used by corresponding load devices 71a and 71b to DC / DC converters 5a and 5b. Control is performed to supply the predicted load powers Wlfa and Wlfb to the load devices 71a and 71b as they are (to supply the actual load powers Wlfa and Wlfb) while converting the bus voltage Vbs so as to be output. Further, the power management apparatus 9 causes the DC / DC converter 5 c to stop the operation of converting the bus voltage Vbs and outputting the load voltage VLc, and causes the load device 71 c to maintain the stopped state. Execute control.

Further, in charge / discharge control processing, power management device 9 executes control similar to that in the charge / discharge control processing in the above-described third processing content to DC power supply 6, and charges planned charge power Wcp as it is. (The same actual charging power as the scheduled charging power Wcp (hereinafter, also referred to as the actual charging power Wcp) is charged).

Also, for example, in the 9 o'clock to 14 o'clock range, the power management apparatus 9 predicts that the predicted generated power Wgf will be larger than the total power Wsm in the next 10 o'clock to 15 o'clock range. Based on the predicted information, the charge / discharge control process and the load device control process in the first process described above are executed in the 10 to 15 o'clock range.

That is, as shown in FIG. 4, in the load device control process, power management device 9 applies load voltages VLa and VLb used by corresponding load devices 71a and 71b to DC / DC converters 5a and 5b. Control is performed to supply the predicted load powers Wlfa and Wlfb to the load devices 71a and 71b as they are (to supply the actual load powers Wlfa and Wlfb) while converting the bus voltage Vbs so as to be output. Further, the power management apparatus 9 executes control on the load device 71c in the stopped state to shift the load device 71c to the operating state, and the above-mentioned surplus power in the load device 71c with respect to the DC / DC converter 5c. The control is executed to supply the difference power = predicted power generation Wgf−total power Wsm (power indicated by a white arrow in FIG. 4) as the load power Wlfc. Thus, by causing the load device 71c to consume the surplus power, it is possible to make the power supplied to each storage battery 11 be the scheduled charging power Wcp. In addition, in the charge and discharge control process, the power management apparatus 9 executes the same control as that of the charge and discharge control process in the third process content described above on the DC power supply device 6. It becomes possible to charge the actual charging power Wcp having the same power value as the scheduled charging power Wcp. Therefore, the charging current of each storage battery 11 can be suppressed to less than the maximum current value.

As described above, the power management apparatus 9 supplies each storage battery 11 with the same actual charging power Wcp as the corresponding planned charging power Wcp in a period in which the predicted generated power Wgf in the solar radiation period becomes larger than the total power Wsm. As described above, by supplying the above-mentioned differential power (surplus power) to the load device 71c as the load power Wlfc and operating it, the generated power Wgbp of the power generation device 3b is effectively used to the storage batteries 11 While increasing the possibility that the current value of the charging current can be lowered as much as possible, the storage batteries 11 are almost fully charged using almost the entire sunshine period.

Further, the power management apparatus 9 executes the second acquisition process, the third acquisition process, the charge power calculation process, the generated power prediction process, the load power prediction process, and the power comparison process described above at each time (period T). Information for defining control contents in charge / discharge control processing and load device control processing to be executed in next coming cycle T (planned charging power Wcp in coming cycle T, predicted generated power Wgf in this cycle T Together with predicted load power Wlf at this cycle T, information on whether or not this cycle T is included in the solar radiation period, information indicating the comparison result of predicted generated power Wgf and total power Wsm, and predicted load power Wlf Information indicating the comparison result of the sum of the above and the predicted generated power Wgf).

As described above, in the DC power feeding system 1, the power management apparatus 9 predicts the result of the comparison in the power comparison process executed before the next cycle T (in the cycle T immediately before this cycle T). If the result is that the generated power Wgf is larger than the total power Wsm (= the sum of the predicted load powers Wlfa and Wlfb + the total of the scheduled charging power Wcp in each storage battery 11) (the predicted generated power Wgf is larger than the total power Wsm In the next cycle T, when it is determined that the control content in the charge / discharge control processing and the load device control processing is defined as the first control content described above, it is executed. Specifically, in the next cycle T, power management device 9 supplies power to bi-directional DC / DC converter 14 from direct current bus 2 to corresponding storage battery 11 for the same actual charging power Wcp as planned charging power Wcp. The charge / discharge control process of charging the storage battery 11 by supplying it is executed, and the same actual load power Wlfa, Wlfb as the predicted load power Wlfa, Wlfb is applied to the corresponding load devices 71a, 71b for each DC / DC converter 5a, 5b. Is executed to supply the DC / DC converter 5c with the difference power between the predicted generated power Wgf and the total power Wsm as the load power Wlfc to operate the corresponding load device 71c. .

Therefore, according to this DC feeding system 1, the surplus power (the difference power between the predicted generated power Wgf and the total power Wsm) generated in the predicted generated power Wgf when the predicted generated power Wgf is larger than the total power Wsm is Can be supplied to the load device 71c in the stopped state and operated, so that the generated power in the power generation device 3b can be effectively used without suppressing the power generation in the power generation device 3b. Further, the power supplied to each storage battery 11 can be reduced to the same as the planned charging power Wcp, so that the power allocated to charging the storage battery 11 becomes too large (that is, the charging current is at or near the maximum current value). It can be avoided that the current value becomes large), thereby avoiding the occurrence of a situation where the deterioration of the storage battery 11 is accelerated. Thereby, deterioration of the storage battery 11 can be delayed.

Further, according to the DC power feeding system 1, the pumping equipment of the power generation device 3c as the pumping type hydroelectric power generation device configured to be able to supply power to the DC bus 2 is used as the load equipment 71c. Since it is possible to cause the power generation device 3c to perform the storage operation with the generated surplus power, the power generation device 3c is caused to perform the power generation operation even when the power generated by the power generation device 3b or the discharge power from the storage battery 11 is insufficient. As a result, it is possible to supply power to the DC bus 2 and to continue supply of the predicted load powers Wlfa and Wlfb to the load devices 71a and 71b. In the above example, although the acquisition time for acquiring the weather prediction information Dwf and the like arrives at a constant period T, the present invention is not limited to this configuration, and a configuration that arrives at different time intervals (For example, it may be configured to arrive at a short time interval in a time zone in which the power generation device 3b using natural regenerative energy operates, and to arrive at a longer time interval in a time zone in which the power generation device 3b stops operation) .

Further, the DC power supply system 1 described above operates on the basis of the charging power of the storage battery 11 _1, BMU12, contactors 13, and a configuration including the DC / DC converter 7 supplies an operating voltage Vop to the power management apparatus 9 Although employed, it is not limited to this. For example, the bus voltage Vbs of the DC bus 2 is sufficiently set within a predetermined voltage range (voltage range of 350 V or more and 400 V or less of DC) by the DC power supply 6 after the power generation device 3b stops power generation and resumes power generation. BMU 12 and contactor 13 are configured such that the capacity of each storage battery 11 is sufficiently large and charging voltage Vba does not fall below the lower limit of the working voltage range. The power management device 9 operates with the charging voltage Vba of at least one of the storage batteries 11 and operates the charging voltage Vba of the corresponding storage battery 11. It can be omitted.

According to the present invention, the present invention can be widely applied to a stand-alone DC power supply system having a natural energy power generation device because the present invention can be effectively used without suppressing power generation in the natural energy power generation device.

DESCRIPTION OF SYMBOLS 1 DC electric power feeding system 2 DC bus 3 Electric power generation apparatus 4 1st converter 5 2nd converter 8 Temperature measurement part 9 Power management apparatus 11 Storage battery 14 Bidirectional DC / DC converter 71 Load apparatus Drg1 Power generation log Drg2 Load log Dwf Weather forecast information VLa, VLb load voltage

Claims (1)

1. A DC bus which is a bus bar of DC power supply,
   A generator that generates electricity based on natural energy,
   A first converter for supplying power generated by the power generation device to the DC bus;
   A storage battery,
   Connected between the storage battery and the DC bus, the generated power supplied to the DC bus and the charging power of the storage battery are bi-directionally converted to power from the DC bus to the storage battery, or A bi-directional converter that supplies power from the storage battery to the DC bus;
   A second converter for converting the DC power of at least one of the generated power and the charging power supplied to the DC bus, and supplying the converted power to a load device;
   A power generation log including weather conditions and generated power when the power generating apparatus operates, and a load log including weather conditions and load power when the load device operates, and chargeable power and weather prediction of the storage battery And a control unit that sequentially acquires information at a predetermined acquisition time,
   The control unit calculates, on the basis of the chargeable power and the weather prediction information, the scheduled charging power for the storage battery in the period up to the acquisition time that arrives next, each time the chargeable power and the weather prediction information are acquired. Charge power calculation processing, power generation prediction processing for calculating predicted power generation of the power generation apparatus in the period based on the power generation log and the weather prediction information, predicted load power of the load device in the period during the load Load power prediction processing calculated based on a log and the weather prediction information, and power comparison processing for comparing the total power of the predicted load power and the planned charging power with the predicted generated power
   Charge / discharge control processing for supplying the planned charging power to the storage battery with respect to the bi-directional converter during the period when it is determined in the power comparison processing that the predicted generated power is larger than the total power; The predicted load power is supplied to the load device for which the predicted load power of the load devices has been calculated with respect to the second converter, and the predicted power generation is performed on the load devices in the stopped state of the load devices. A DC power supply system that executes a load device control process of supplying power of a difference power between power and the total power.

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