JP2011091968A - Power feeding apparatus and controller used therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power feeding apparatus capable of improving power conversion efficiency as the entire of a plurality of power converters; and to provide a controller used therefor. <P>SOLUTION: A share deciding section 15 of the controller 1 sequentially calculates the total input power of all AC/DC converters 2a, 2b, 2c when the total output current is allocated by using each of six kinds of allocation patterns in a pattern storage section 14. Further, the share deciding section 15 calculates the conversion efficiency of power in the entire converter group 20 from the relation between the total input power and the total output power of all the AC/DC converters 2a, 2b, 2c, and uses an allocation pattern at which the conversion efficiency is the maximum as an applied pattern. A layout control section 16 allocates the total output current in accordance with the applied pattern, and instructs the magnitude of supplied power to be output from each converter to each of the AC/DC converters 2a, 2b, 2c. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a power supply device having a power converter that converts input power into desired output power, and a controller used therefor.

  Conventionally, AC power from a commercial power source is converted into DC power by a large-capacity and high-efficiency AC / DC converter (AC / DC converter) disposed in a distribution board such as a house, and a DC load (DC A distribution system that distributes DC power from a distribution board via a distribution path to a load that operates by receiving power supply has been proposed (for example, see Patent Document 1).

  The power distribution system described in Patent Document 1 uses not only DC power obtained by converting power from a commercial power supply but also DC power obtained from these distributed power supplies by using a secondary battery, a solar battery, or the like as a distributed power supply. Electricity can also be used together. These distributed power supplies are provided with a DC / DC converter as a power converter for stepping up or stepping down the output voltage.

  Here, it is known that a general power converter changes the power conversion efficiency according to the magnitude of its output current (output power). Therefore, Patent Document 1 adopts a configuration in which the output of another distributed power source is controlled so that an AC / DC converter as a power converter is operated in a state close to the maximum conversion efficiency. Patent Document 1 also describes that a plurality of AC / DC converters are juxtaposed and the number of AC / DC converters to be operated is increased or decreased according to the magnitude of power supplied to the load.

JP 2009-153301 A

  By the way, in the conventional power distribution system, when power is supplied to a load from a power supply device having a plurality of power converters (AC / DC converter, DC / DC converter, etc.), the plurality of power converters as a whole There is no idea to increase the power conversion efficiency. For this reason, although attention is paid to some of the power converters, it operates with high conversion efficiency, but the conversion efficiency of the plurality of power converters as a whole is low, and as a result, the power supply device as a whole performs power conversion. The resulting loss can be significant. For example, in the example of Patent Document 1, the AC / DC converter operates in a state close to the maximum conversion efficiency, but the conversion efficiency of the DC / DC converters of other distributed power supplies is low, so that the power distribution system as a whole is converted. Efficiency can be low.

  The present invention has been made in view of the above-described reasons, and an object thereof is to provide a power supply device capable of increasing the power conversion efficiency of the plurality of power converters as a whole and a controller used therefor. Do

  The invention of claim 1 has a converter group composed of a plurality of power converters each converting input power into desired output power, and the sum of supply currents output from all the power converters of the converter group Is supplied to the load as a total output current, and the power conversion efficiency in each power converter varies according to the magnitude of the respective supply current, and the power supply efficiency and the conversion efficiency for each power converter An efficiency storage unit in which a correspondence relationship is stored in advance, a pattern storage unit in which a plurality of allocation patterns representing rules of allocation of total output current to each power converter in the converter group are stored in advance, and a converter group Applying one allocation pattern in the pattern storage unit using the total output instruction unit instructing the total output current required for the output, the total output current instructed by the total output instruction unit, and the conversion efficiency stored in the efficiency storage unit Patter And an assignment control unit that controls the output of each power converter so that the total output current is assigned to each power converter according to the selected application pattern. When the total output current is allocated to the power converters of the converter group according to each allocation pattern in the storage unit, the total input power in the entire converter group is calculated for each allocation pattern using the conversion efficiency in the efficiency storage unit. An allocation pattern that minimizes the sum of the input powers is selected as an application pattern.

  According to this configuration, the total output current, which is the sum of the supply currents output from the converter group composed of a plurality of power converters, is calculated according to the application pattern selected by the sharing determination unit. Therefore, even if the total output current is constant, the supply current output from each power converter varies depending on the selected application pattern. Here, the assignment determination unit is the sum of the input power in the entire converter group when the total output current is allocated to the power converters of the converter group according to each of the plurality of allocation patterns stored in advance in the pattern storage unit. Is calculated for each allocation pattern using the conversion efficiency in the efficiency storage unit, and an allocation pattern that minimizes the sum of the input power is selected as an application pattern. Therefore, by assigning the total output current according to the selection pattern, the power conversion efficiency of the plurality of power converters constituting the converter group as a whole is higher than when assigning according to another assignment pattern. . As a result, there is an advantage that the loss that occurs during power conversion can be reduced as a whole power supply apparatus.

  According to a second aspect of the present invention, in the first aspect of the present invention, the total output is supplied to the pattern storage unit by a supply current at which each conversion efficiency is maximum for at least one power converter of the converter group. An allotment pattern that assigns the remainder of the total output current to any one power converter in the converter group after assigning the current, and the total output current for all power converters in the converter group between the power converters A total averaging pattern that is assigned so as to reduce the variation in supply current, and a quasi-averaged pattern that is assigned so as to reduce the variation in supply current between power converters for a part of the converters in the converter group. Among these, at least two or more allocation patterns are stored in advance.

  According to this configuration, the allocation of the total output current to each power converter in the converter group is relatively simple regardless of which allocation pattern of the bias pattern, the total average pattern, and the semi-average pattern is selected. Since calculation is possible, the processing load when assigning the total output current can be reduced.

  According to a third aspect of the present invention, in the second aspect of the present invention, the bias pattern is a first pattern in which the surplus is assigned to a power converter different from the power converter to which the supply current that maximizes the conversion efficiency is assigned. And a second pattern in which the remaining power is allocated to any one of the power converters to which the supply current that maximizes the efficiency conversion is allocated.

  According to this configuration, since the uneven weight pattern is further finely divided into the first pattern and the second pattern, the choice when the assignment determination unit selects the application pattern increases, and the total output current is determined according to a more appropriate allocation pattern. Can be assigned.

  According to a fourth aspect of the present invention, there is provided the AC / DC converter according to any one of the first to third aspects, wherein at least one power converter of the converter group converts AC power into DC power. It is characterized by that.

  According to this configuration, even in a power supply device that converts AC power from a commercial power source into DC power and provides it to the load, the power conversion efficiency of the plurality of power converters constituting the converter group as a whole The loss generated during power conversion can be reduced as a whole power supply apparatus.

  The invention of claim 5 is characterized in that, in any of the inventions of claims 1 to 4, all the power converters of the converter group share a change characteristic of power conversion efficiency with respect to a supply current. To do.

  According to this configuration, all the power converters in the converter group share the same change characteristics of the power conversion efficiency with respect to the supply current. Therefore, if a combination of current values to be assigned is determined, each current value is assigned to any power value. Even if it assigns to a converter, the power conversion efficiency as a whole of a plurality of power converters which constitute a converter group becomes constant. Therefore, there are fewer options when the sharing determination unit selects an application pattern, and the processing of the sharing determination unit can be simplified.

  According to a sixth aspect of the present invention, in the fifth aspect of the invention, the sharing determination unit determines a combination of the supply currents that minimizes the sum of the input power in the entire converter group, and each supply A unique allocation unit that determines to which power converter the current is allocated, and an integration monitoring unit that monitors the integrated value of the amount of current supplied from each power converter for each power converter is provided. The allocating unit determines an allocation destination of each supply current so that a large supply current is allocated in order from a power converter having a small integrated value of the supply current amount.

  According to this configuration, since the large supply current is allocated in order from the power converter having the smallest integrated value of the supply current amount by the specific allocation unit, the variation in the integrated value of the supply current amount among the power converters can be reduced. it can. That is, there is an advantage that a plurality of power converters can be used without bias, and it is possible to avoid shortening the life of the specific power converter by only overusing the specific power converter.

  According to a seventh aspect of the present invention, in any one of the first to fourth aspects of the present invention, at least one of the power converters in the converter group has a power conversion efficiency change characteristic with respect to a supply current that has other power. It is different from the converter.

  According to this configuration, since at least one power converter of the converter group is different from other power converters in changing characteristics of power conversion efficiency with respect to a supply current, not only a combination of current values to be allocated, Depending on which power converter each current value is assigned to, the power conversion efficiency of the plurality of power converters constituting the converter group as a whole changes. For this reason, the choice when the assignment determination unit selects the application pattern increases, and the total output current can be assigned according to a more appropriate assignment pattern.

  The invention of claim 8 is used in the power supply device according to any one of claims 1 to 7, wherein the efficiency storage unit, the pattern storage unit, the total output instruction unit, and the sharing determination unit, The allocation control unit is provided in an apparatus main body.

  According to this configuration, the existing power that has a converter group including a plurality of power converters and supplies the total sum of supply currents output from all the power converters of the converter group as a total output current to the load. An effect similar to that of any one of claims 1 to 7 can be obtained by simply changing the system configuration to the supply device.

  In the present invention, the sharing determination unit allocates the total output current to the power converters of the converter group according to each of a plurality of allocation patterns stored in advance in the pattern storage unit. The total is calculated for each allocation pattern using the conversion efficiency in the efficiency storage unit, and the allocation pattern that minimizes the total sum of the input power is selected as the application pattern. Therefore, by allocating the total output current according to the selection pattern, there is an advantage that the power conversion efficiency of the plurality of power converters constituting the converter group as a whole is higher than in the case of following other allocation patterns. is there.

It is a schematic block diagram of the principal part of the power distribution system of Embodiment 1 of this invention. It is a schematic block diagram which shows the whole structure same as the above. It is a conversion efficiency-output characteristic figure of the AC / DC converter used for the same as the above. It is a flowchart which shows operation | movement of the assignment determination part same as the above. It is a schematic block diagram of the principal part which shows the other structure same as the above. It is explanatory drawing which shows operation | movement of Embodiment 2 of this invention.

(Embodiment 1)
As shown in FIG. 2, the power distribution system of this embodiment includes AC / DC converters 2a, 2b, and 2c as power converters (hereinafter simply referred to as “AC / DC converter 2” unless otherwise distinguished). , A power storage device 3 and a solar cell 4 as a distributed power source, and a controller 1 that controls operations of the AC / DC converter 2, the power storage device 3, the solar cell 4, and the like. This power distribution system is configured to supply supply currents output from each of the AC / DC converter 2, the power storage device 3, and the solar battery 4 to the plurality of loads 6 via the power distribution path 5. The load 6 illustrated here is a DC load that operates by receiving supply of DC power, and includes, for example, an LED (light emitting diode) lighting device, a home alarm device, and the like.

  A plurality (three in this case) of AC / DC converters 2 are connected in parallel to the commercial power supply AC, and a group of converter groups 20 is constituted by the plurality of AC / DC converters 2a, 2b, and 2c. . These AC / DC converters 2a, 2b, and 2c convert AC power from the commercial power source AC into DC power, respectively, and supply currents output from all the AC / DC converters 2a, 2b, and 2c constituting the converter group 20 Is connected to the power distribution path 5 so that the sum of the two is supplied to the load 6 as a total output current.

  Here, each AC / DC converter 2a, 2b, 2c is a so-called switching power supply device, and the power conversion efficiency when converting AC power to DC power as shown in FIG. It has a conversion efficiency-output characteristic that changes in accordance with the size of. In the present embodiment, the AC / DC converter 2 has the maximum conversion efficiency when the supply current is the maximum efficiency value Ip lower than the rated current value, and all the AC / DC converters 2a, 2b, 2c in the converter group 20 are used. And a common conversion efficiency-output characteristic (conversion efficiency curve). That is, the power conversion efficiency in the AC / DC converter 2 is maximized when the supply current is at the maximum efficiency value Ip, and decreases as it increases or decreases from the maximum efficiency value Ip.

  The power storage device 3 has a secondary battery (not shown) as a main component, charges the secondary battery with DC power distributed from the AC / DC converter 2 and the solar battery 4 via the distribution path 5, and A charge / discharge circuit (not shown) for discharging the battery power to the distribution path 5 and a control circuit (not shown) for controlling the operation of the charge / discharge circuit are provided. The charge / discharge circuit is provided with a DC / DC converter as a power converter that boosts or lowers the discharge voltage of the secondary battery. Further, the solar cell 4 is provided with a DC / DC converter (not shown) as a power converter for stepping up or stepping down the output voltage, and the generated power of the solar cell 4 passes through the DC / DC converter. Are configured to be sent to the distribution path 5.

  Accordingly, a constant DC voltage is applied to the distribution path 5 from the AC / DC converters 2 a, 2 b, 2 c, the power storage device 3, and the solar cell 4.

  The controller 1 is connected to the power distribution path 5 and is consumed by the supply current output from each of the AC / DC converter 2, the power storage device 3, and the solar battery 4, the remaining capacity of the secondary battery, and the load 6. The power is monitored to control the operation of the AC / DC converter 2, the charge / discharge operation of the power storage device 3 (including the operation of the DC / DC converter), and the like. Here, a communication function is provided between the controller 1 and the AC / DC converter 2 and further between the controller 1 and the control circuit of each distributed power supply so that data can be transmitted via the power distribution path 5. The communication function performs communication by superimposing a communication signal on a DC voltage applied to the load 6 through the distribution path 5. Since this type of communication function is well known, detailed description thereof is omitted. The controller 1 and the converter group 20 constitute a power supply device.

  Next, a more specific configuration of the power supply apparatus including the controller 1 and the AC / DC converters 2a, 2b, and 2c will be described with reference to FIG.

  Each of the AC / DC converters 2a, 2b, and 2c includes a communication unit 21 that communicates with the controller 1 and the like via the distribution path 5, a current control circuit 22 that converts input power into DC power, and a current control circuit. And an output control unit 23 that controls the magnitude of the supply current output to the distribution path 5 by performing feedback control of the control circuit 22. In FIG. 1, the internal configuration is shown only for one AC / DC converter 2a, but the other AC / DC converters 2b and 2c have the same configuration.

  The controller 1 includes a communication unit 11 that communicates with the AC / DC converters 2a, 2b, 2c, and the like via the power distribution path 5, and a total output instruction unit 12 that calculates a total output current that needs to be output from the converter group 20. And. The total output instruction unit 12 converts the remaining capacity and charge / discharge capacity of the secondary battery collected via the communication unit 11, the operation status (power generation amount) of the solar cell 4, and the current consumption at the load 6. The total output current to be output by the AC / DC converters 2a, 2b, 2c of the unit group 20 is calculated. That is, when the current output from the power storage device 3 and the solar battery 4 to the distribution path 5 is smaller than the current consumed by the load 6 connected to the distribution path 5, the difference is output from the converter group 20. The total output current to be obtained. If the system configuration is such that there is no power storage device or solar cell, the current consumption at the load 6 is the total output current.

  Further, the controller 1 includes an efficiency storage unit 13 in which a correspondence relationship between the supply current and the conversion efficiency is stored in advance for each AC / DC converter 2a, 2b, 2c, and a total to each AC / DC converter 2a, 2b, 2c. And a pattern storage unit 14 in which a plurality of types of allocation patterns representing rules for how to allocate output currents are stored in advance. The controller 1 also includes an assignment determination unit 15 that determines which assignment pattern stored in the pattern storage unit 14 is used to assign the total output current, and the assignment selected by the assignment determination unit 15. An allocation control unit 16 that actually gives an instruction to allocate the total output current according to the pattern is provided.

  Here, since all the AC / DC converters 2a, 2b, and 2c have the same conversion efficiency-output characteristics, the efficiency storage unit 13 stores, for example, in Table 1 below based on the conversion efficiency-output characteristics shown in FIG. Such an efficiency table indicating the correspondence between the supply current and the conversion efficiency is stored. In the example of Table 1, the power conversion efficiency corresponding to the supply current up to the rated current value (4.0 [A]) of the AC / DC converters 2a, 2b, and 2c is 0.1 [A] increments of the supply current. It is represented by That is, each of the AC / DC converters 2a, 2b, 2c has the maximum power conversion efficiency (here 75 [%] when the output current supplied is the maximum efficiency value (here 2.0 [A]) Ip. ]). Hereinafter, description will be made on the assumption that the efficiency table of Table 1 is used.

  When the total output current is output from the converter group 20, the allocation pattern stored in the pattern storage unit 14 is for each of the plurality of AC / DC converters 2 a, 2 b, and 2 c that constitute the converter group 20. It specifies how the total output current is allocated. That is, the allocation pattern needs to be output to each of the AC / DC converters 2a, 2b, and 2c constituting the converter group 20 in order to cause the converter group 20 to output a certain total output current. It represents a rule for determining the magnitude of the supply current. In the present embodiment, the pattern storage unit 14 stores six types of allocation patterns “No. 1” to “No. 6” shown in Table 2 below. Note that the allocation patterns of “No. 1” to “No. 6” are merely examples, and only a part of them can be used as an allocation pattern, or other allocation patterns can be used.

  Each allocation pattern in Table 2 will be described below. The “assignment example” column at the right end of Table 2 shows an example of current values assigned to the AC / DC converters 2a, 2b, and 2c according to each assignment pattern when the total output current is 5.0 [A]. Show.

  The six types of allocation patterns “No. 1” to “No. 6” include the uneven distribution patterns of “No. 1” and “No. 2” and the total average of “No. 3” and “No. 4”. The patterns are roughly classified into “No. 5” and “No. 6” quasi-averaged patterns.

  First, the bias pattern (Nos. 1 and 2) is a total output current for each supply current (maximum efficiency value Ip) at which each conversion efficiency is maximum for at least one AC / DC converter 2 in the converter group 20. , And the remainder of the total output current is assigned to any one of the AC / DC converters 2. For this reason, in this bias pattern, an emphasis is placed on increasing the conversion efficiency of the individual AC / DC converters 2a, 2b, and 2c.

  Here, the first pattern of “No. 1” and the second pattern of “No. 2” are different in the handling of the remaining of the total output current. That is, in the first pattern, the remaining current is allocated to one AC / DC converter 2 other than the AC / DC converter 2 to which the supply current having the maximum efficiency value Ip has already been allocated. Therefore, if the remaining current is equal to or less than the maximum efficiency value Ip, the AC / DC converter 2 to which the remaining current is assigned outputs a supply current equal to or less than the maximum efficiency value Ip. Therefore, for example, when the total output current is 5.0 [A], the total output current is assigned to each AC / DC converter 2a, 2b, 2c as 2 [A], 2 [A], 1 [A] is assigned.

  On the other hand, in the second pattern, the remaining current is added to any one of the AC / DC converters 2 to which the supply current of the maximum efficiency value has already been assigned. Accordingly, a supply current larger than the maximum efficiency value Ip is output from the AC / DC converter 2 to which the remaining current is allocated. Therefore, for example, when the total output current is 5.0 [A], the total output current is assigned to each AC / DC converter 2a, 2b, 2c by 3 [A], 2 [A], 0 [A] is assigned at a time.

  Further, the total average pattern (Nos. 3 and 4) is the total output current between all the AC / DC converters 2a, 2b and 2c constituting the converter group 20 between the AC / DC converters 2a, 2b and 2c. In this pattern, as much as possible is assigned so as to reduce the variation in the supply current at the same time. In short, in the total averaging pattern, the magnitude of the total output current is divided by the number of AC / DC converters 2a, 2b, 2c constituting the converter group 20, and the result is the respective AC / DC converters 2a, 2b, 2c. Allocated to Therefore, in this total averaging pattern, the conversion efficiency of the individual AC / DC converters 2a, 2b, and 2c is not emphasized, and the operation of the plurality of AC / DC converters 2a, 2b, and 2c constituting the converter group 20 is not performed. Emphasis will be placed on balance.

  Here, the uniform pattern of “No. 3” and the residual pattern of “No. 4” differ depending on whether they are equally allocated at the decimal level or even at the integer level. That is, in the uniform pattern, when the total output current is assigned to all the AC / DC converters 2a, 2b, and 2c, the supply current of each AC / DC converter 2a, 2b, and 2c has a decimal point (here, a decimal first) Allocate evenly up to the value of. Here, when the remainder after the decimal point is generated, the remaining current is also allocated to all the AC / DC converters 2a, 2b, 2c as evenly as possible. Therefore, for example, when the total output current is 5.0 [A], the total output current is 1.7 [A], 1.7 for each AC / DC converter 2a, 2b, 2c in the “No. 3” allocation pattern. [A] and 1.6 [A] are assigned.

  On the other hand, in the residual pattern, when assigning the total output current to all the AC / DC converters 2a, 2b, 2c, only the integer part of the supply current of each AC / DC converter 2a, 2b, 2c is equalized. Make assignments as follows. Here, when a residue occurs, only an integer part of the remaining current is allocated to all AC / DC converters 2a, 2b, and 2c as evenly as possible. Therefore, for example, when the total output current is 5.0 [A], the total output current is assigned to each AC / DC converter 2a, 2b, 2c as 2 [A], 2 [A], 1 [A] is assigned. When the remaining current includes a value after the decimal point, the value after the decimal point is assigned to one of the AC / DC converters 2 for allocation. At this time, as the AC / DC converter 2 to which the current value after the decimal point is assigned, it is desirable to select one that increases the power conversion efficiency by adding the current value.

  Further, the quasi-averaged pattern (Nos. 5 and 6) indicates that the total output current of these AC / DC converters 2 is a part of the AC / DC converters 2 constituting the converter group 20 (here, two). In this pattern, as much as possible, the variation in supply current between the converters 2 is reduced. In short, in the quasi-averaged pattern, the magnitude of the total output current is divided by the number of AC / DC converters 2 that are part of the converter group 20 (two in this case), and the result is a part of these AC / DC converters. / DC converter 2 is allocated. Therefore, in this quasi-averaged pattern, at least one AC / DC converter 2 stops operating. The control of the output of each AC / DC converter 2 performed by the allocation control unit 16 includes not only controlling the magnitude of the supply current but also controlling the operation of the AC / DC converter 2 in this way. . Here, the relationship between the uniform pattern of “No. 5” and the residual pattern of “No. 6” is the same as that of the above-described all average pattern (No. 3, 4). Omitted.

  Therefore, for example, when the total output current is 5.0 [A], the total output current is assigned to each AC / DC converter 2a, 2b, 2c as 2 [A], 2 [A], 1 [A] is allocated, and 2 [A], 2 [A], and 1 [A] are allocated in “No. 6” allocation patterns 2a, 2b, and 2c.

  By the way, the assignment determination unit 15 of the controller 1 uses all the six types of allocation patterns in the pattern storage unit 14 and assigns the total output current to all the AC / DC converters 2a and 2b in the converter group 20. , 2c (hereinafter referred to as “total input power”). Furthermore, the sharing determination unit 15 determines the entire converter group 20 based on the relationship between the total input power and the sum of the output powers of all the AC / DC converters 2a, 2b, and 2c (hereinafter referred to as “total output power”). The conversion efficiency of power (hereinafter referred to as “total conversion efficiency”) is calculated, and an allocation pattern that maximizes the total conversion efficiency is obtained. The allocation pattern having the maximum total conversion efficiency obtained in this manner is an application pattern used for actual total output current allocation.

  Specifically, the assignment determination unit 15 first receives an instruction of the total output current value from the total output instruction unit 12, and each of the converter groups 20 that constitutes the converter group 20 when the total output current is allocated according to each allocation pattern. The supply current of AC / DC converter 2a, 2b, 2c is calculated | required. Then, the sharing determination unit 15 uses the supply currents of the AC / DC converters 2a, 2b, and 2c thus obtained based on the efficiency table in the efficiency storage unit 13, and the AC / DC converters 2a, 2b, and 2c. Find the power conversion efficiency at. As a result, the supply current and the conversion efficiency are obtained for each AC / DC converter 2a, 2b, 2c, and each AC / DC converter 2a is used using these and a known output voltage (voltage applied to the distribution path 5). , 2b, 2c can be calculated. The total sum of the input powers for all AC / DC converters 2a, 2b, and 2c thus determined is the total input power, and the total conversion efficiency can be determined from the relationship between the total input power and the known total output power. The sharing determination unit 15 stores the obtained total conversion efficiency in a temporary storage unit (not shown) for each allocation pattern.

  Next, the operation of the assignment determination unit 15 will be described with reference to the flowchart of FIG. Here, it is assumed that the output voltages of the AC / DC converters 2a, 2b, and 2c are 100 [V], the total output current is 5.0 [A], and the total output power is 500 [W].

  The sharing determination unit 15 first executes a process of calculating the total conversion efficiency for the allocation pattern “No. 1” in Table 2 (S1). At this time, in the allocation pattern of “No. 1” in Table 2, since the total output current of 5.0 [A] is allocated by 2 [A], 2 [A], and 1 [A], each AC / DC The output power of converters 2a, 2b, and 2c is 200 [W], 200 [W], and 100 [W], respectively. In this case, the conversion efficiencies of the AC / DC converters 2a, 2b, and 2c are found to be 75%, 75%, and 70%, respectively, from the efficiency table in Table 1. The input power of each AC / DC converter 2a, 2b, 2c is obtained as 267 [W], 267 [W], 143 [W]. Therefore, the total input power in this case is 677 [W], and the total conversion efficiency is 73.9 [%] in relation to the total output power 500 [W]. The sharing determination unit 15 stores the obtained total conversion efficiency in the temporary storage unit.

  Furthermore, the assignment determination unit 15 sequentially performs the process of calculating the total conversion efficiency for each of the above-described allocation patterns for each of the allocation patterns from “No. 2” to “No. 6” (S2 to S6). The total conversion efficiency obtained in step 1 is temporarily stored for each allocation pattern. In this way, the sharing determination unit 15 acquires the total conversion efficiency for all the allocation patterns for the total output current instructed from the total output instruction unit 12 by a simple calculation.

  Thereafter, the sharing determination unit 15 determines one allocation pattern that maximizes the obtained total conversion efficiency from all allocation patterns (S7), and uses the allocation pattern for actual total output current allocation. The pattern is selected (S8 to S13). It is assumed that the total conversion efficiency in the temporary storage unit is deleted after the application pattern is selected. For example, when the total conversion efficiency is maximized at the same rate in a plurality of allocation patterns, such as lowering the priority of selection from “No. 1” to “No. 6”, which allocation pattern is given priority. It is desirable to prescribe whether to select.

  The application pattern (any allocation pattern) selected by the assignment determination unit 15 as described above is notified to the allocation control unit 16. Upon receiving the notification of the application pattern, the allocation control unit 16 assigns the total output current according to the application pattern, and obtains the magnitude of the supply current to be output from each AC / DC converter 2a, 2b, 2c. The allocation control unit 16 transmits a current command representing the obtained magnitude of the supplied current to each AC / DC converter 2a, 2b, 2c through the communication unit 11.

  In the AC / DC converters 2a, 2b, and 2c that have received the current command from the controller (assignment control unit 16) 1 in the communication unit 21, the output control unit 23 controls the current control circuit 22 according to the current command. Thereby, the supply current designated by the current command is output from each AC / DC converter 2a, 2b, 2c.

  The controller 1 selects an application pattern every time the magnitude of the total output current changes beyond a predetermined allowable range, and reassigns the total output current to each AC / DC converter 2a, 2b, 2c. And However, the present invention is not limited to this, and the selection of the application pattern and the reallocation of the total output current may be performed periodically.

  According to the above-described configuration, the AC / DC converters 2a, 2b, and 2c of the converter group 20 output supply currents having the magnitudes assigned to the AC / DC converters 2a, 2b, and 2c according to the application pattern. Will be. Here, since the application pattern is an allocation pattern selected so that the total conversion efficiency is maximized from among a plurality of types of allocation patterns, the AC / DC converters 2a constituting the converter group 20 by following the application pattern. , 2b, 2c as a whole has a relatively high power conversion efficiency. As a result, it is possible to reduce the loss that occurs during the power conversion in the converter group 20, improve the power conversion efficiency of the entire power supply device, and suppress the consumption of the commercial power supply AC as low as possible. There are advantages.

  By the way, when conversion efficiency-output characteristics are common in all AC / DC converters 2a, 2b, and 2c constituting the converter group 20 as in this embodiment, each supply current assigned according to the application pattern is set to any of the supply currents. The total conversion efficiency is constant even when assigned to the AC / DC converters 2a, 2b, 2c. In other words, as long as the combination of supply currents follows the application pattern, the total conversion efficiency does not change even if the assignment destination of each supply current is exchanged between AC / DC converters 2a, 2b, and 2c. For example, in the allocation pattern of “No. 1”, when the total output current of 5 [A] is allocated 2 [A], 2 [A], and 1 [A] at a time, the AC / Regardless of the DC converter 2a, 2b, 2c, the total conversion efficiency is the same.

  Therefore, as another configuration example of the present embodiment, as shown in FIG. 5, a combination determination unit 15a that determines a combination of supply currents to be assigned to the sharing determination unit 15, and each of the supply currents to any AC / DC converter 2a , 2b, 2c can be considered to have a unique allocation unit 15b that determines whether the allocation is performed. In this configuration, first, the combination determination unit 15a determines the combination of supply currents that maximizes the total conversion efficiency according to the allocation pattern, and then the specific allocation unit 15b determines the application pattern including the supply current allocation destination. become.

  In this case, it may be possible to randomly determine the supply current allocation destination to be allocated by the specific allocation unit 15b. However, priority is given to the AC / DC converters 2a, 2b, and 2c, and the higher priority is assigned in descending order. It is desirable to have a supply current allocated. Here, the priority is not fixedly determined, but is variably determined so that the burden is not biased to some AC / DC converters 2a, 2b, and 2c.

  Specifically, as shown in FIG. 5, an integration monitoring unit 17 that monitors an integrated value of the amount of current supplied from each AC / DC converter 2a, 2b, 2c for each AC / DC converter 2a, 2b, 2c; The controller 1 is provided with a priority determination unit 18 that determines priority based on the monitoring result of the integration monitoring unit 17.

  The integration monitoring unit 17 monitors the supply current for each of the AC / DC converters 2a, 2b, 2c constituting the converter group 20, and the integrated value [Ah] of the supply current amount is displayed on a table as shown in Table 3 below. to manage. Integration is performed periodically (for example, every second). The integrated value of the supply current amount may be performed by each AC / DC converter instead of the controller 1.

  The priority determination unit 18 determines the priorities of the AC / DC converters 2a, 2b, and 2c so that the priorities increase in ascending order of the integrated values. Therefore, in the example of Table 3, the priority of the AC / DC converter 2c is “high”, the priority of the AC / DC converter 2b is “medium”, and the priority of the AC / DC converter 2a is “low”. The priority is regularly updated, and here, it is updated every day at a predetermined time (for example, 6:00 am).

  As described above, in the configuration in which the assignment destination is determined based on the priority of the AC / DC converters 2a, 2b, and 2c, a large supply current is assigned in order from the AC / DC converters 2a, 2b, and 2c having the smallest integrated value of the supply current. Therefore, the variation in the amount of supplied current between the AC / DC converters 2a, 2b, 2c can be reduced. That is, by distributing the operating time evenly and averaging the operating rates of the plurality of AC / DC converters 2a, 2b, 2c, the burden on some AC / DC converters 2a, 2b, 2cn is biased. Can be prevented. Therefore, it is possible to avoid shortening the service life of some of the AC / DC converters 2a, 2b, and 2c due to overuse, and the power distribution system can be provided without requiring replacement of the AC / DC converters 2a, 2b, and 2c. The period of continuous use becomes longer.

  In the above embodiment, an example in which the conversion efficiency-output characteristics of the AC / DC converters 2a, 2b, and 2c are stored in the efficiency storage unit 13 as an efficiency table is shown. However, the present invention is not limited to this example. An arithmetic expression indicating a correspondence relationship with the efficiency may be stored in the efficiency storage unit 13. In this case, the sharing determination unit 13 can obtain the conversion efficiencies of the AC / DC converters 2a, 2b, and 2c using the arithmetic expression.

  Further, when the total output current calculated by the total output instruction unit 12 exceeds the sum of the rated currents of the AC / DC converters 2a, 2b, and 2c constituting the converter group 20, the fact is detected. It is also possible to provide the controller 1 with a function of suppressing power supply to the load 6. In this case, when the power supply to the load 6 is suppressed, the power supply to the load 6 is stopped in order from the lowest priority according to the priority order determined in advance for each load 6, or the power consumption of the load 6 is reduced. The total output current required is reduced by switching to mode. The power supply to the load 6 is stopped by a switch (not shown) provided for each system on the distribution path 5 or by interrupting the power supply by the load 6 itself.

(Embodiment 2)
In the power distribution system of the present embodiment, at least one of the plurality of AC / DC converters 2a, 2b, 2c constituting the converter group 20 has a conversion efficiency-output characteristic (conversion efficiency curve) different from the others. The point is different from the power distribution system of the first embodiment.

  That is, in this embodiment, not only the combination of the supply currents assigned to the plurality of AC / DC converters 2a, 2b, 2c, but also depending on which of the AC / DC converters 2a, 2b, 2c each supply current is assigned to. Total conversion efficiency varies. For example, in the allocation pattern of “No. 1” described in the first embodiment, when the total output current of 5 [A] is allocated 2 [A], 2 [A], and 1 [A] each, the supply current is The total conversion efficiency varies depending on which of the AC / DC converters 2a, 2b, and 2c is 1 [A].

  Therefore, in the present embodiment, six types of allocation patterns (hereinafter referred to as “upper pattern”) of “N0.1” to “No. 6” in Table 2 described in the first embodiment are further assigned to supply currents. The patterns finely classified (hereinafter referred to as “lower pattern”) are used as allocation patterns. The sharing determination unit 15 calculates the total conversion efficiency for each of the allocation patterns finely classified as described above, and selects the allocation pattern having the maximum total conversion efficiency as an application pattern.

  Hereinafter, a specific example will be described. Here, the three AC / DC converters constituting the converter group 20 have different conversion efficiencies and output characteristics in all of 2a, 2b, and 2c, and supply currents are 2 [A], 3 [A], and 4 respectively. It is assumed that the power conversion efficiency is maximum at [A] (that is, each maximum efficiency value Ip is 2 [A], 3 [A], 4 [A]).

  As shown in FIG. 6, the sharing determination unit 15 receives an instruction of the total output current, and assigns each of the six types of upper patterns “N0.1” to “No. 6” further classified into a plurality of lower patterns. The total conversion efficiency is obtained for the pattern. For example, assuming that the total output current is 7 [A], the distribution pattern of “No. 1” is the supply having the maximum efficiency value Ip for any of the three AC / DC converters 2a, 2b, and 2c. There are three sub-patterns depending on whether the current is allocated. That is, a first sub-pattern assigned to each AC / DC converter 2a, 2b, 2c by 2 [A], 3 [A], 2 [A], and 0 [A], 3 [A], 4 There are a second lower pattern assigned by [A] and a third lower pattern assigned by 2 [A], 1 [A], and 4 [A]. The sharing determination unit 15 calculates the total conversion efficiency (X [%], Y [%], Z [%]) for each of these subordinate patterns.

  According to the configuration of the present embodiment described above, even when the converter group 20 is configured by combining AC / DC converters 2a, 2b, and 2c of different models, the conversion efficiency of the converter group 20 as a whole is increased. can do. In addition, by using the subordinate pattern that is finely classified in consideration of the supply current allocation destination, there are more choices when selecting the allocation pattern that maximizes the total conversion efficiency than when only the upper pattern is used. . As a result, there is an advantage that the total output current can be allocated with a more optimal application pattern in terms of the total conversion efficiency.

  In the present embodiment, the converter group 20 is described as being configured only by the AC / DC converter 2. However, for example, the DC / DC converter in the power storage device 3 may be included in the converter group 20. Good. In this case, the conversion efficiency-output characteristic (conversion efficiency curve) of the DC / DC converter is stored in the efficiency storage unit 13.

  Other configurations and functions are the same as those of the first embodiment.

  By the way, when the power supply to the load 6 is provided only by the single AC / DC converter 2, the supply current of the AC / DC converter 2 is uniquely determined by the power consumption of the load 6. It is difficult to operate 2 in a state close to the maximum conversion efficiency. On the other hand, when the sum of the supply currents from the plurality of AC / DC converters 2a, 2b, and 2c is supplied to the load 6 as in the above embodiments, each AC / DC depends on how the total output current is allocated. Since the supply currents of the converters 2a, 2b, and 2c are variable, the AC / DC converters 2a, 2b, and 2c can be easily operated in a state close to the maximum conversion efficiency.

  Moreover, the AC / DC converter 2 has a characteristic that the conversion efficiency peaks when the supply current is the maximum efficiency value Ip close to the rated value as shown in FIG. 3, and the conversion efficiency decreases as the distance from the maximum efficiency value Ip increases. . Therefore, when power supply to the load 6 is covered by a single large-capacity AC / DC converter 2, when the power consumption of the load 6 is small, the conversion efficiency is lowered because the supply current is significantly different from the rated output value. . On the other hand, in the present embodiment, by using a plurality of AC / DC converters 2 having relatively small capacities, the AC / DC converters 2a, 2b, 2c can be set to the maximum efficiency value Ip even when the power consumption of the load 6 is small. The conversion efficiency can be improved. Further, the use of a plurality of AC / DC converters 2a, 2b, and 2c has an advantage that the variable range of current that can be supplied to the load 6 is wider than when a single AC / DC converter 2 is used. There is also. Furthermore, even if some of the AC / DC converters 2 are stopped, the supply current can be supplied from the other AC / DC converters 2, and the availability of the system is improved.

1 controller 2a, 2b, 2c AC / DC converter (power converter)
6 Load 12 Total Output Instruction Unit 13 Efficiency Storage Unit 14 Pattern Storage Unit 15 Allocation Determination Unit 16 Allocation Control Unit 20 Converter Group

Claims (8)

  Each has a converter group consisting of a plurality of power converters that convert input power into desired output power, and the sum of the supply currents output from all the power converters of the converter group as a total output current to the load In the power supply device to be supplied, the power conversion efficiency in each power converter varies according to the magnitude of the respective supply current, and the correspondence between the supply current and the conversion efficiency is stored in advance for each power converter. An efficiency storage unit, a pattern storage unit in which a plurality of allocation patterns representing rules of allocation of total output current to each power converter of the converter group are stored in advance, and a total output current required for the converter group One allocation pattern in the pattern storage unit is selected as an application pattern using the total output instruction unit to be instructed, the total output current instructed by the total output instruction unit, and the conversion efficiency stored in the efficiency storage unit A sharing determination unit, and an allocation control unit that controls the output of each power converter so that the total output current is allocated to each power converter according to the selected application pattern. When the total output current is allocated to the power converters of the converter group according to the allocation pattern, the total input power in the entire converter group is calculated for each allocation pattern using the conversion efficiency in the efficiency storage unit, and the input power A power supply device that selects an allocation pattern that minimizes the sum of the two as an application pattern.   In the pattern storage unit, the total output current is allocated to the at least one power converter of the converter group for each supply current that maximizes the respective conversion efficiency, and then the remainder of the total output current is converted. Unbalance pattern to be assigned to any one power converter in the converter group, and total averaging that assigns the total output current to all power converters in the converter group so that the variation in supply current among the power converters is reduced At least two or more allocation patterns are pre-stored among the pattern and a quasi-averaged pattern that is allocated to a power converter that is part of the converter group so as to reduce variation in supply current between the power converters. The power supply device according to claim 1, wherein:   The bias pattern includes a first pattern in which the remaining power is allocated to a power converter different from the power converter to which a supply current that maximizes conversion efficiency is allocated, and power that is allocated a supply current in which efficiency conversion is maximized. The power supply device according to claim 2, wherein the power supply device is divided into a second pattern in which a remaining power is allocated to any one of the converters.   4. The power according to claim 1, wherein at least one of the power converters of the converter group includes an AC / DC converter that converts AC power into DC power. 5. Feeding device.   5. The power supply device according to claim 1, wherein all the power converters of the converter group share a change characteristic of power conversion efficiency with respect to a supply current. 6.   The sharing determination unit determines a combination determination unit that determines a combination of the supply currents that minimizes the total sum of input power in the entire converter group, and determines which power converter is assigned to each supply current. And a unique monitoring unit that monitors the integrated value of the supplied current amount from each power converter for each power converter, and the unique allocated unit is a power converter that has a small integrated value of the supplied current amount. 6. The power supply apparatus according to claim 5, wherein an allocation destination of each supply current is determined so that a large supply current is allocated in order from the device.   5. The power converter according to claim 1, wherein at least one of the power converters of the converter group is different from other power converters in a change characteristic of power conversion efficiency with respect to a supply current. The power supply device described in 1. The power supply device according to claim 1, wherein the efficiency storage unit, the pattern storage unit, the total output instruction unit, the assignment determination unit, and the allocation control unit are provided. A controller characterized by comprising a main body.

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