JP2009159730A - Dc power distribution system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a DC power distribution system efficiently utilizing secondary batteries contained in a distributed power supply. <P>SOLUTION: The control unit 40 of a controller 4 allows a discharge device 3 to carry out discharge until the residual capacity of a secondary battery 1 is lowered to less than 100% of a prescribed ratio with respect to a capacity at full charging, when a power system AC is not interrupted. The controller allows a charge device 2 to carry out charging, when the residual capacity of the secondary battery 1 is lowered to the prescribed ratio. More practically, the DC power charged in the secondary battery 1 is supplied to a load L at the time other than the power failure time in the power system AC, as long as the residual capacity of the secondary battery 1 is not below the residual capacity needed against a power failure. Thus, the needed DC power is always charged in the secondary battery 1 even at AC power failure, and the DC power discharged from the secondary battery 1 is supplied to the load L to efficiently utilize the secondary battery 1, regardless of whether the power system AC is interrupted. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a DC power distribution system.

In recent years, an AC / DC converter (AC / DC converter) that converts AC power supplied from a power system into DC power and a distributed power source such as a solar cell or a fuel cell are linked to distribute DC power to a DC load. DC power distribution systems are attracting attention. Such a DC power distribution system includes an emergency power supply as a distributed power supply for supplying DC power to a DC load in an emergency such as a power failure at night. The emergency power source has a secondary battery and a charger, and the charger charges the secondary battery with DC power supplied from a DC / DC converter or a distributed power source such as a solar cell or a fuel cell. In such an emergency, the secondary battery is discharged to supply DC power to the DC load. Patent Document 1 describes an uninterruptible power supply device that can continuously supply DC power even in the above-described emergency.
JP 2000-184615 A

  By the way, in the conventional DC power distribution system, like the uninterruptible power supply device described in Patent Document 1, the secondary battery is always kept in a fully charged state in preparation for an emergency. For this reason, the DC power stored in the secondary battery is hardly used except in an emergency.

  This invention is made | formed in view of the said situation, The objective is to provide the direct current power distribution system which can utilize effectively the secondary battery contained in a distributed power supply.

  In order to achieve the above object, the invention of claim 1 is an AC / DC converter that converts AC power supplied from a power system into DC power, one or more distributed power sources that supply DC power, and AC A DC / DC converter and a distributed power source each connected to one or more DC loads to distribute DC power, and at least one distributed power source includes a secondary battery and an AC / DC converter to the power distribution path Device for charging a secondary battery with DC power distributed through the battery, a discharge device for sending DC power discharged from the secondary battery to a distribution path, and a charging operation and discharge device for the secondary battery by the charging device And a control device that controls the discharge operation from the secondary battery to the distribution path by the control device, and the control device has a remaining capacity of the secondary battery of less than 100% with respect to the capacity at the time of full charge except during a power failure of the power system To a certain percentage of In order to supply power to the DC load, the discharging device performs a discharging operation, and when the remaining capacity of the secondary battery decreases to the predetermined ratio, the charging device performs a charging operation. The discharge operation of the discharge device is continued even when the remaining capacity decreases below the predetermined ratio.

  According to the first aspect of the present invention, the control device controls the discharge device so that the discharge device continues the discharge operation even when the remaining capacity of the secondary battery falls below a predetermined ratio of less than 100% at the time of power failure of the power system. In addition, the discharge device performs a discharge operation to supply power to the DC load until the remaining capacity of the secondary battery is reduced to the predetermined ratio with respect to the capacity at the time of full charge except at the time of power failure of the power system and the secondary battery When the remaining capacity of the battery is reduced to the predetermined rate, the control device controls the charging device and the discharging device so that the charging device performs the charging operation. Therefore, from the secondary battery not only at the time of power failure but also at the time of power failure The secondary battery can be effectively used by supplying the DC power to be discharged to the load. In addition, since the secondary battery is charged and discharged within a range that does not cause overcharge and overdischarge except during a power failure in the power system, the life of the secondary battery can be extended.

  According to a second aspect of the present invention, in the first aspect of the present invention, the control device increases the predetermined ratio according to the degree of aging of the secondary battery.

  According to the invention of claim 2, even if the full charge capacity of the secondary battery is reduced due to aging, the DC power necessary for power failure is supplied by increasing the predetermined rate at which discharge is permitted except during power failure. Can do.

  According to a third aspect of the present invention, in the first or second aspect of the invention, the control device includes a determination unit that determines whether or not a predetermined condition for causing the charging device to start a charging operation is satisfied. When the remaining capacity of the secondary battery decreases to the predetermined ratio, the charging device is caused to perform a charging operation when the determination unit determines that the predetermined condition is satisfied.

  The invention of claim 4 is the invention of any one of claims 1 to 3, comprising a solar cell as a distributed power source, and the charging device is distributed from the solar cell or the AC / DC converter via the distribution path. The secondary battery is charged with DC power, and the control device causes the charging device to perform a charging operation using DC power distributed from the AC / DC converter in a specific time zone at night, and the remaining capacity of the secondary battery is reduced. The charging operation is stopped when the capacity reaches less than 100% with respect to the capacity at the time of full charge and higher than the predetermined ratio.

  According to the invention of claim 4, in order to charge the secondary battery with surplus power fed from the solar battery during the day, the secondary battery is fed with DC power fed from the AC / DC converter in the night time zone. It is possible to increase the efficiency of the entire system by not charging the battery until it is fully charged.

  In the invention of claim 5, in the invention of claim 4, the control device stops the charging operation of the charging device up to the predetermined value when the next day's weather is predicted to be sunny, and the next day's weather is cloudy or rainy. Is expected to cause the charging device to perform a charging operation until the secondary battery is fully charged.

  According to the invention of claim 5, when the next day's weather is cloudy or rainy, it is not expected to charge the secondary battery with surplus power of the solar battery. The efficiency of the entire system can be increased by charging the secondary battery to the full charge with the DC power fed from the AC / DC converter to the belt.

  According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the control device includes a weather prediction unit that predicts the weather by detecting at least one of humidity and atmospheric pressure, and the weather of the next day predicted by the weather prediction unit. The charging operation of the charging device is controlled according to the above.

  According to the invention of claim 6, the efficiency of the entire system can be improved by controlling the charging operation of the charging device based on the local weather predicted by the weather prediction means.

  According to a seventh aspect of the present invention, in the fifth aspect of the invention, the control device has means for acquiring the prediction information from the server providing the weather prediction information via the Internet, and the next day's weather acquired from the server. The charging operation of the charging device is controlled according to the prediction information.

  According to the invention of claim 7, since the charging operation of the charging device is controlled in accordance with the weather prediction information acquired from the server via the Internet, the weather prediction accuracy can be improved.

  ADVANTAGE OF THE INVENTION According to this invention, the secondary battery contained in a distributed power supply can be used effectively.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  As shown in FIG. 1A, the DC power distribution system of the present embodiment is an AC / DC converter (AC / DC converter) AD that converts AC power supplied from a power system (commercial power system) AC into DC power. A distributed power source PV composed of solar cells, a distributed power source SB that has the secondary battery 1 and supplies DC power, an AC / DC converter AD, and distributed power sources PV and SB, each of which has a plurality of DC loads (hereinafter referred to as It is abbreviated as “load.”) A distribution path Lp that is connected to L and distributes DC power is provided.

  The distributed power source SB includes a secondary battery 1, a charging device 2 that charges the secondary battery 1 with DC power distributed from the AC / DC converter AD and the distributed power source PV via the distribution path Lp, and the secondary battery 1. The discharge device 3 for sending the DC power discharged from the power distribution path Lp, and the control for controlling the charging operation of the secondary battery 1 by the charging device 2 and the discharging operation from the secondary battery 1 to the distribution path Lp by the discharging device 3 Device 4. The secondary battery 1 consists of a nickel metal hydride battery or a lithium ion battery. The discharge device 3 is provided with a DC / DC converter that boosts or lowers the discharge voltage of the secondary battery 1.

  As shown in FIG. 1B, the control device 4 includes a control unit 40 including a microcomputer as a main component, a terminal voltage of the secondary battery 1, an electric quantity measuring unit 41 that measures a discharge current and a charging current, A counter unit 42 that counts the number of times the secondary battery 1 is charged / discharged, a storage unit 43 that stores information (data table) such as various threshold values, remaining capacity of the secondary battery 1 and the degree of deterioration, and the humidity and pressure And a battery temperature measuring unit 45 for measuring the battery temperature of the secondary battery 1 (for example, the surface temperature of the secondary battery 1 and the ambient temperature around the secondary battery 1). Yes. The storage unit 43 stores a data table of charge / discharge characteristics corresponding to the type of the secondary battery 1 (nickel metal hydride battery, lithium ion battery, etc.), a data table of the degree of aging deterioration, and the like. The secondary battery 1 based on the terminal voltage and current (discharge current, charging current) measured by the quantity measuring unit 41, the battery temperature measured by the battery temperature measuring unit 45, and the data table of the charge / discharge characteristics and the aging deterioration degree. It has a function to calculate the remaining capacity and the degree of deterioration over time. The control unit 40 also has a function of determining the power failure of the power system AC by monitoring the output voltage of the AC / DC converter AD, and a function of predicting the weather based on the humidity and atmospheric pressure detected by the weather sensor unit 44. Have.

  Next, the operation of the distributed power supply SB that is the gist of the present invention will be described.

  When the power system AC is not out of power, the control unit 40 of the control device 4 is configured such that the remaining capacity of the secondary battery 1 is a fully charged capacity (hereinafter referred to as “full charge capacity”) as shown in FIG. .) With respect to the predetermined ratio (for example, an arbitrary ratio of 50% to 80%) of less than 100%, the discharging operation by the discharge device 3 is performed until the remaining capacity of the secondary battery 1 reaches the predetermined ratio. When the voltage drops, the charging device 2 is charged. However, the predetermined ratio is set to a value that can secure a remaining capacity necessary for supplying DC power necessary for a predetermined time to a predetermined load L when a power failure occurs in the power system AC. That is, the DC power charged to the secondary battery 1 is supplied to the load L in a range where the remaining capacity of the secondary battery 1 does not fall below the necessary remaining capacity at the time of the power failure except during the power system AC power failure. Even when a power failure occurs, the DC power required at the time of the power failure is always charged in the secondary battery 1, so the DC power discharged from the secondary battery 1 not only during a power failure but also during a power failure is loaded L The secondary battery 1 can be effectively used by supplying power to. Moreover, since the secondary battery 1 is charged and discharged within a range that does not cause overcharge and overdischarge except during a power failure of the power system AC, the life of the secondary battery 1 can be extended. Needless to say, the control unit 40 of the control device 4 continues the discharge operation of the discharge device 3 even when the remaining capacity of the secondary battery 1 drops below the predetermined ratio during a power failure of the power system AC.

  By the way, since the charge capacity of the secondary battery 1 deteriorates over time due to repeated charge and discharge, DC power necessary for a predetermined time is supplied to a predetermined load L at the time of a power failure of the power system AC. In order to always ensure the remaining capacity necessary for this, it is necessary to increase the predetermined ratio according to the degree of aging of the secondary battery 1 as shown in FIG. Here, as shown in FIG. 4A, the degree of aging of the secondary battery 1 is greatly influenced by the battery temperature. For example, the battery temperature T is T = 20 ° C., T = 45 ° C., T = 60. When compared at the time of ° C., as the battery temperature T is higher, the degree of aging deterioration (the degree of decrease in the full charge capacity with respect to the number of charge / discharge cycles) tends to increase.

  Therefore, in the control unit 40 of the control device 4, the number of times of charging / discharging counted by the counter unit 42 and the battery temperature measured by the battery temperature measuring unit 45 are always stored in the storage unit 43 in association with each other, and according to the battery temperature. Based on the relationship between the number of times of charging / discharging and the maximum capacity (full charge capacity) of the secondary battery 1 (characteristic shown in FIG. 4A), the degree of aging (full charge capacity) at that time is determined and stored in advance. The predetermined ratio is increased in comparison with the data table stored in the unit 43 (see FIG. 4B). For example, in the data table shown in FIG. 4B, the predetermined ratio (initial value) when the aging deterioration degree is zero (full charge capacity is 100%) is 50.0%, and the aging deterioration degree is 10% ( When the full charge capacity is 90%), the predetermined ratio is 55.6%, when the degree of aging is 20% (full charge capacity is 80%), the predetermined ratio is 62.5%, and the degree of aging is 30% ( When the full charge capacity is 70%, the predetermined ratio is 71.4%, when the degree of aging is 40% (full charge capacity is 60%), the predetermined ratio is 83.3%, and the degree of aging is 50% ( The predetermined ratio when the full charge capacity is 50%) is set to 100.0%. Thus, the remaining capacity of the secondary battery 1 can always be maintained at a certain level or higher by increasing the predetermined ratio according to the degree of aging of the secondary battery 1.

  In addition, the secondary battery 1 must be charged with DC power supplied from the AC / DC converter AD at night when power cannot be supplied from the distributed power source PV made of solar cells. On the other hand, since the amount of power (power generation) supplied by the distributed power source PV, which is a solar cell, often exceeds the amount of power consumed by the load L during sunny days, the secondary battery 1 uses surplus power from the distributed power source PV. Is desirable to increase the efficiency of the entire system. Furthermore, power companies that provide the power grid AC offer a service that discounts electricity charges in the late night hours when power demand is reduced compared to the daytime, so it is possible to reduce costs by charging in such late night hours. .

  Therefore, in the control unit 40 of the control device 4, when the remaining capacity of the secondary battery 1 falls below a predetermined ratio, a predetermined condition (specifically, it is a midnight time zone in which the power rate is discounted or Battery power distribution PV, the surplus power being generated) is determined to be satisfied, and when it is determined that the condition is satisfied, the charging device 2 is used to perform a charging operation. Yes. Further, the control unit 40 predicts the weather based on the humidity and atmospheric pressure detection results detected by the weather sensor unit 44 by the control unit 40 of the control device 4 when charging the secondary battery 1 in the midnight time zone, and the next day ( Alternatively, if the weather on the day is predicted to be cloudy or rainy, the charging device 2 is charged until the secondary battery 1 is fully charged (see FIG. 3A), but the weather is predicted to be sunny. In this case, when the remaining capacity of the secondary battery 1 reaches a ratio (second ratio) lower than 100% and higher than the predetermined ratio with respect to the charging capacity, the charging operation of the charging device 2 is stopped (FIG. 3 ( b)). In order to charge the secondary battery 1 with the surplus electric power fed from the distributed power source (solar cell) PV during the day by the control unit 40 of the control device 4 performing the above-described control operation, the night time zone Then, the secondary battery 1 is not fully charged with the DC power supplied from the AC / DC converter AD, and when the next day's weather is cloudy or rainy, the secondary power 1 is supplied with the surplus power of the distributed power source (solar battery) PV. Since the secondary battery 1 cannot be expected to be charged, when it is predicted to be cloudy or rainy, the secondary battery 1 is fully charged with the DC power supplied from the AC / DC converter AD in the late-night time zone. By doing so, the efficiency of the entire system can be increased.

  Here, the control device 4 is provided with means for acquiring the prediction information from the server that provides the weather prediction information via the Internet, and the control unit 40 determines whether the control unit 40 is in accordance with the weather prediction information for the next day acquired from the server. If the charging operation 2 is controlled, the weather prediction accuracy can be increased as compared with the case where the weather is predicted from the detection result of the weather sensor unit 44. However, the means for acquiring weather prediction information from the server via the Internet can be realized by using a conventionally known network communication technique, and therefore, detailed illustration and description thereof will be omitted.

  Here, another embodiment of the present invention will be described with reference to FIG. The embodiment described below assumes a detached house as a building to which the present invention is applied, but does not prevent the technical idea of the present invention from being applied to an apartment house. In the house H, as shown in FIG. 4, in addition to the distributed power source SB having the secondary battery 1, the charging device 2, the discharging device 3, and the control device 4, the distributed power source PV having a solar cell and the distributed power source having a fuel cell are provided. FV is connected to the output side of the AC / DC converter AD via the cooperative control unit 113. Then, DC power is supplied to the DC device 102 through the distribution path Wdc branched from the output end of the cooperative control unit 113. Between the cooperative control unit 113 and the DC device 102, the current flowing through the distribution path Wdc is monitored, and when an abnormality is detected, the power supply from the cooperative control unit 113 to the DC device 102 is limited or cut off on the distribution path Wdc. A DC breaker 114 is provided.

  The distribution path Wdc is a DC power supply path and is also used as a communication path, and is a device connected to the distribution path Wdc by superimposing a communication signal for transmitting data on a DC voltage using a high-frequency carrier wave. Communication between them. This technique is similar to a power line carrier technique in which a communication signal is superimposed on an AC voltage in a power line that supplies AC power.

  The power distribution path Wdc is connected to the home server 116 via the AC / DC converter AD. The in-home server 116 is a main device for constructing a home communication network (hereinafter referred to as “home network”), and communicates with a subsystem constructed by the DC device 102 in the home network.

  In the example shown in the drawing, as an subsystem, an illumination system comprising an information equipment system K101 comprising an information-system DC device 102 such as a personal computer, a wireless access point, a router, and an IP telephone, and an illumination system DC equipment 102 such as a lighting fixture. K102, K105, an intercom system K103 including a DC device 102 for handling visitors and monitoring intruders, a residential alarm system K104 including a DC device 102 for an alarm system such as a fire detector, and the like. Each subsystem constitutes a self-supporting distributed system, and can operate even with the subsystem alone.

  The DC breaker 114 described above is provided in association with a subsystem. In the illustrated example, four DC breakers are associated with the information equipment system K101, the lighting system K102 and the intercom system K103, the house alarm system K104, and the lighting system K105. 114 is provided. When a plurality of subsystems are associated with one DC breaker 114, a connection box 121 that divides the system of the DC supply line Wdc is provided for each subsystem. In the illustrated example, a connection box 121 is provided between the illumination system K102 and the intercom system K103.

  As the information equipment system K101, there is provided an information equipment system K101 composed of a DC equipment 102 connected to a DC outlet 131 arranged in advance in the house H (constructed when the house H is constructed) in the form of a wall outlet or a floor outlet.

  The lighting systems K102 and K105 include a lighting system K102 including a lighting fixture (DC device 102) arranged in advance in the house H, and a lighting fixture (DC device 102) connected to a hook ceiling 132 arranged in advance on the ceiling. An illumination system K105 is provided. At the time of interior construction of the house H, the contractor attaches the lighting fixture to the hook ceiling 132, or the resident himself attaches the lighting fixture.

  In addition to using an infrared remote control device, a control instruction for the lighting apparatus that is the DC device 102 constituting the lighting system K102 can be given using a communication signal from the switch 141 connected to the power distribution path Wdc. That is, the switch 141 has a communication function together with the DC device 102. In addition, a control instruction may be given by a communication signal from another DC device 102 in the home network or the home server 116 regardless of the operation of the switch 141. The instructions to the lighting fixture include lighting, extinguishing, dimming, and blinking lighting.

  Since any DC device 102 can be connected to the DC outlet 131 and the hooking ceiling 132 described above and DC power is output to the connected DC device 102, the DC outlet 131 and the hooking ceiling 132 are distinguished below. When it is not necessary, it is called “DC outlet”.

  These DC outlets have a plug-in connection port into which a contact (not shown) provided directly on the DC device 102 or a contact (not shown) provided via a connection line is inserted into the body. The contact receiver that directly contacts the contact inserted into the connection port is held by the container. That is, the direct current outlet supplies power in a contact manner. When the DC device 102 connected to the DC outlet has a communication function, a communication signal can be transmitted through the power distribution path Wdc. A communication function is provided not only in the DC device 102 but also in the DC outlet.

  The home server 116 not only is connected to the home network, but also has a connection port connected to the wide area network NT that constructs the Internet. When the in-home server 116 is connected to the wide area network NT, it is possible to receive services from the center server 200 that is a computer server connected to the wide area network NT.

  The service provided by the center server 200 includes a service that enables monitoring and control of equipment (including mainly the DC equipment 102 but also other equipment having a communication function) connected to the home network through the wide area network NT. is there. This service makes it possible to monitor and control devices connected to the home network using a communication terminal (not shown) having a browser function such as a personal computer, Internet TV, or mobile phone.

  The in-home server 116 has both functions of communication with the center server 200 connected to the wide area network NT and communication with equipment connected to the home network, and identification information on equipment in the home network ( Here, it is assumed that an IP address is used).

  The home server 116 enables monitoring and control of home devices through the center server 200 from a communication terminal connected to the wide area network NT by using a communication function with the center server 200. The center server 200 mediates between home devices and communication terminals on the wide area network NT.

  When monitoring and controlling home devices from a communication terminal, monitoring and control requests are stored in the center server 200, and the home device periodically performs one-way polling communication to monitor from the communication terminal. And receive control requests. With this operation, it is possible to monitor and control devices in the house from the communication terminal.

  Further, when an event that should be notified to the communication terminal, such as a fire detection, occurs in the home device, the home device notifies the center server 200, and the center server 200 notifies the communication terminal by e-mail.

  An important function among the communication functions with the home network in the home server 116 is the detection and management of devices constituting the home network. The home server 116 automatically detects devices connected to the home network by applying UPnP (Universal Plug and Play). The home server 116 includes a display device 117 having a browser function, and displays a list of detected devices on the display device 117. The display device 117 has a configuration with a touch panel type or an operation unit, and can perform an operation of selecting desired contents from options displayed on the screen of the display device 117. Therefore, the user (contractor or householder) of the home server 116 can monitor or control the device on the screen of the display device 117. The display device 117 may be provided separately from the home server 116.

  The in-home server 116 manages information related to device connection, and grasps the type, function, and address of the device connected to the home network. Accordingly, the devices in the home network can be operated in conjunction with each other. Information on the connection of the device is automatically detected as described above. In order to operate the device in an interlocking manner, the device itself is automatically associated with the attribute held by the device itself, and the home server 116 is configured as a personal computer. It is also possible to connect various information terminals and use the browser function of the information terminals to associate devices.

  Each device holds the relationship of the interlocking operation of the devices. Therefore, the device can operate in an interlocked manner without passing through the home server 116. By associating the linked operations for each device, for example, by operating a switch that is a device, it is possible to turn on or off the lighting fixture that is the device. In many cases, the association of the interlocking operations is performed within the subsystem, but the association beyond the subsystem is also possible.

  Incidentally, the AC / DC converter AD is housed in the distribution board 110 and is connected to the power system AC through the main breaker 111 housed in the distribution board 110. The cooperative control unit 113 connected to the output side of the AC / DC converter AD controls the distribution of power from the DC power system including the AC / DC converter AD and the distributed power sources SB, PV, FV to the DC devices 102. It has a function to do.

  Since the driving voltage of the DC device 102 is selected from a plurality of types of voltages according to the device, a DC / DC converter is provided in the cooperative control unit 113, and the DC voltage obtained from the DC power system and the distributed power sources SB, PV, FV is used. It is desirable to convert it to the required voltage. Normally, one type of voltage is supplied to one subsystem (or DC device 102 connected to one DC breaker 114), but three or more wires are used for one subsystem. A plurality of types of voltages may be supplied. Alternatively, it is possible to adopt a configuration in which the DC supply line Wdc is of a two-wire type and the voltage applied between the lines is changed with time. The DC / DC converter may be provided in a plurality of dispersed manners like the DC breaker.

  In the above configuration example, only one AC / DC converter AD is shown, but a plurality of AC / DC converters AD can be arranged in parallel, and a plurality of AC / DC converters AD are provided. Sometimes, it is desirable to increase or decrease the number of AC / DC converters AD that are operated according to the magnitude of the load.

  The AC / DC converter AD, the cooperative control unit 113, the DC breaker 114, and the distributed power sources SB, PV, and FV described above are provided with a communication function, and the AC / DC converter AD and the distributed power sources SB, PV, FV, etc. It is possible to perform a cooperative operation to cope with a load state including the DC device 102. The communication signal used for this communication is transmitted in the form of being superimposed on the DC voltage in the same manner as the communication signal used for the DC device 102.

  In the above example, the AC / DC converter AD is arranged in the distribution board 110 in order to convert the AC power output from the main breaker 111 into DC power by the AC / DC converter AD. On the output side of 111, an AC supply line is branched into a plurality of systems by a branch breaker (not shown) provided in the distribution board 110, and an AC / DC converter AD is provided on each system AC supply line. You may employ | adopt the structure converted into direct-current power.

  In this case, since a DC power system can be provided for each floor or room of the house H, the DC power system can be managed for each unit, and the DC device 102 that uses DC power can be managed. Since the distance of the power distribution path Wdc in between becomes short, the power loss by the voltage drop in the power distribution path Wdc can be reduced. Further, the main breaker 111 and the branch breaker are housed in the distribution board 110, and the AC / DC converter AD, the cooperative control unit 113, the DC breaker 114, and the home server 116 are housed in a separate board from the distribution board 110. May be.

1 shows an embodiment of the present invention, (a) is a system configuration diagram, (b) is a block diagram of a control device. (A) and (b) are operation | movement explanatory drawings same as the above. (A) and (b) are operation | movement explanatory drawings same as the above. (A) is explanatory drawing explaining the change of the aging deterioration degree with respect to the battery temperature of a secondary battery, (b) is explanatory drawing of the data table for changing a predetermined ratio according to aging deterioration degree. It is a system block diagram which shows other embodiment.

Explanation of symbols

AC power system AD AC / DC converter PV Distributed power supply (solar cell)
SB Distributed power supply Lp Distribution path L Load 1 Secondary battery 2 Charging device 3 Discharging device 4 Control device

Claims (7)

An AC / DC converter that converts AC power supplied from the power system into DC power, one or more distributed power sources that supply DC power, and one or more DC loads each of the AC / DC converter and the distributed power source And a distribution path that distributes DC power by connecting to
At least one distributed power source distributes a secondary battery, a charging device that charges the secondary battery with DC power distributed from the AC / DC converter via the distribution path, and DC power discharged from the secondary battery. A discharge device to be sent to the road, and a control device for controlling the charging operation of the secondary battery by the charging device and the discharging operation from the secondary battery to the distribution path by the discharging device,
The control device performs a discharging operation by the discharging device to supply power to the DC load until the remaining capacity of the secondary battery is reduced to a predetermined ratio of less than 100% with respect to the capacity at the time of full charge except at the time of power failure of the power system. When the remaining capacity of the secondary battery decreases to the predetermined rate, the charging device performs a charging operation, and when the power system fails, even if the remaining capacity of the secondary battery decreases below the predetermined rate, the discharging operation of the discharging device DC distribution system characterized by continuing the operation.   2. The DC power distribution system according to claim 1, wherein the control device increases the predetermined ratio according to a degree of deterioration of the secondary battery over time.   The control device includes a determination unit that determines whether or not a predetermined condition for causing the charging device to start the charging operation is satisfied. When the remaining capacity of the secondary battery decreases to the predetermined ratio, the determination unit 3. The DC power distribution system according to claim 1, wherein the charging device is caused to perform a charging operation when it is determined that the predetermined condition is satisfied. Equipped with solar cells as a distributed power source,
The charging device charges the secondary battery with the DC power distributed through the distribution path from the solar cell or the AC / DC converter,
The control device stops the charging operation when the remaining capacity of the secondary battery reaches a rate lower than 100% and higher than the predetermined rate with respect to the fully charged capacity in a specific time zone at night. The DC power distribution system according to any one of claims 1 to 3.   The control device stops the charging operation of the charging device up to the predetermined value when the next day's weather is predicted to be sunny, and the secondary battery is fully charged when the next day's weather is predicted to be cloudy or rainy. The direct current distribution system according to claim 4, wherein the charging device is caused to perform a charging operation up to.   The control device includes a weather prediction unit that predicts the weather by detecting at least one of humidity and atmospheric pressure, and controls the charging operation of the charging device according to the weather of the next day predicted by the weather prediction unit. The DC power distribution system according to claim 5.   The control device includes means for acquiring the prediction information from the server that provides the weather prediction information via the Internet, and controls the charging operation of the charging device according to the weather prediction information of the next day acquired from the server. The DC power distribution system according to claim 5.

Images