Distributed power supply management device, distributed power supply management method, and distributed power supply management program

Abstract

To preferably control a frequency of a power supply system with commands from a decentralized power supply management device to respective PCSs.SOLUTION: There is provided a decentralized power supply management device which manages a plurality of decentralized power supplies in an electric power system comprising the plurality of decentralized power supplies and one or more loads, and the decentralized power supply management device comprises an acquisition part which acquires load information on sizes of the loads, and a calculation part which calculates, based upon the load information, a command value for active electric power to be generated by at least some of the plurality of decentralized power supplies so that the difference between a convergent value of the frequency of the electric power system and a target frequency value becomes small, wherein the calculation part has a vector generation part which generates a vector including the load information and command value, and a matrix generation part which generates a connection matrix representing connection relation between the plurality of decentralized power supplies and nodes including the one or more loads, and the calculation part calculates the command value based upon the product of the connection matrix and the vector.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a distributed power supply management device, a distributed power supply management method, and a distributed power supply management program. [Background technology]

[0002] Patent Document 1 states that "a control method and system for a microgrid that supplies a substantially constant voltage to a power distribution system is provided" (abstract). Patent Document 2 states that "the active power and reactive power output from the power converter to the power grid are appropriately controlled" (abstract). In power systems, a technique using droop control to restore a fluctuating frequency to a reference value is known (for example, Non-Patent Document 1). [Prior art document] [Patent documents] [Patent Document 1] JP 2017-060380 A [Patent Document 2] JP 2018-023202 A [Non-patent literature] [Non-Patent Document 1] J.W. Simpson-Porco, F. Dorfler, and F. Bullo, "Synchronization and Power Sharing for Droop-Controlled Inverters in Islanded Microgrids," Automatica, vol. 49, no. 9, pp. 2603-2611, 2013 Summary of the Invention [Problem to be solved by the invention]

[0003] It is desirable to be able to control the frequency of the power system by sending commands from the distributed power management device to each PCS. [Means for solving the problem]

[0004] A first aspect of the present invention provides a distributed power management device. The distributed power management device manages a plurality of distributed power sources in a power system including the plurality of distributed power sources and one or more loads. The distributed power management device includes an acquisition unit that acquires load information about the magnitude of the load, and a calculation unit that calculates, based on the load information, a command value for active power to be generated by at least some of the plurality of distributed power sources so as to reduce the difference between the convergence value of the frequency in the power system and the target frequency value. The calculation unit includes a vector generation unit that generates a vector including the load information and the command value, and a matrix generation unit that generates a connection matrix that represents the connection relationships between nodes including the plurality of distributed power sources and one or more loads. The calculation unit calculates the command value based on the product of the connection matrix and the vector.

[0005] The calculation unit may calculate the command value based on the absolute value of the product of the connection matrix and the vector.

[0006] The calculation unit may calculate the command value so that the absolute value of the product of the connection matrix and the vector is minimized.

[0007] When each row of the connection matrix corresponds to a node, each column of the connection matrix corresponds to a wire connecting the nodes, and the vector is a column vector, the calculation unit may calculate a command value based on the product of the transpose of the connection matrix and the vector.

[0008] The calculation unit may calculate the command value so that the sum of the active power consumed by one or more loads approaches the sum of the active power generated by the plurality of distributed power sources.

[0009] The calculation unit may calculate the command value so that the total of the active power consumed by the one or more loads is equal to the total of the active power generated by the plurality of distributed power sources.

[0010] The calculation unit may calculate the command value so as to maximize the stability of the synchronous state in the power system.

[0011] The calculation unit may calculate the command value so as to converge most quickly to the most stable synchronous state.

[0012] The calculation unit may calculate a linear programming problem in which the constraints are that the total active power consumed by one or more loads is equal to the total active power generated by the multiple distributed power sources, and that the command value is greater than or equal to 0 and less than or equal to a predetermined planned value, and the objective function is to minimize the absolute value of the product of the connection matrix and the vector.

[0013] The calculation of the command value by the calculation unit, the transmission of the calculated command value to at least some of the distributed power sources by the transmission unit, the acquisition of new load information by the acquisition unit, and the calculation of the new command value by the calculation unit may be repeated until the difference between the convergence value of the frequency and the target value of the frequency becomes equal to or less than a predetermined value.

[0014] A second aspect of the present invention provides a distributed power management method. The distributed power management method manages a plurality of distributed power sources in a power system including the plurality of distributed power sources and one or more loads. The distributed power management method includes an acquisition step of acquiring load information about the magnitude of the load, and a calculation step of calculating, based on the load information, a command value for active power to be generated by at least some of the plurality of distributed power sources so as to reduce the difference between a convergence value of the frequency in the power system and a target frequency value. The calculation step includes a vector generation step of generating a vector including the load information and the command value, and a matrix generation step of generating a connection matrix representing the connection relationships between nodes including the plurality of distributed power sources and one or more loads. The calculation step calculates the command value based on the product of the connection matrix and the vector.

[0015] A third aspect of the present invention provides a distributed power supply management program that causes a computer to function as a distributed power supply management device.

[0016] The above summary of the invention does not list all of the features of the present invention, and subcombinations of these features may also be inventions. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a conceptual diagram showing an example of a power grid system to which a distributed power management apparatus 100 according to an embodiment of the present invention is applied. [Figure 2] 2 is a diagram showing a difference ωsync between a convergence value ω of the frequency and a target value ωo of the frequency in the power system 2. FIG. [Figure 3] 1 is a diagram illustrating an example of a schematic configuration of a distributed power management apparatus 100 according to a first embodiment of the present invention. [Figure 4A] FIG. 2 is a diagram illustrating an example of a schematic configuration of a calculation unit 140. [Figure 4B] 2 is a diagram showing an example of a connection relationship between nodes in a power system 2. FIG. [Figure 4C] 4B shows an example of a connection matrix B when the connection relationship between nodes in the power system 2 is as shown in FIG. 4B. [Figure 5] 3 is a flowchart showing an example of a management method in the first embodiment of the present invention. [Figure 6] 10 is a flowchart illustrating an example of a command value calculation process. [Figure 7] FIG. 10 is a diagram illustrating an example of a schematic configuration of a distributed power management apparatus 100 according to a second embodiment of the present invention. [Figure 8] 10 is a flowchart showing an example of a management method according to a second embodiment of the present invention. [Figure 9] 10 is a flowchart showing another example of the management method in the second embodiment of the present invention. [Figure 10] 10 is a flowchart showing another example of the management method in the second embodiment of the present invention. [Figure 11] 22 illustrates an example computer 2200 in which aspects of the present invention may be embodied, in whole or in part. DETAILED DESCRIPTION OF THE INVENTION

[0018] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0019] 1 is a conceptual diagram showing an example of a power grid system to which a distributed power management apparatus 100 according to an embodiment of the present invention is applied. The distributed power management apparatus 100 of this example controls the active power output by a plurality of distributed power sources 10-1, 10-2, 10-3, and 10-4 to adjust the frequency ω of the power grid 2.

[0020] The power system 2 includes a plurality of distributed power sources 10-1, 10-2, 10-3, and 10-4 (sometimes collectively referred to as distributed power sources 10). The power system 2 includes one or more loads 20-1, 20-2, 20-3, 20-4, 20-5, and 20-6 (sometimes collectively referred to as loads 20). The power system 2 may be a microgrid that supplies power only from the distributed power sources 10.

[0021] The distributed power sources 10 are small-scale power generation facilities that are distributed and located in different locations. The distributed power sources 10 may be power sources such as photovoltaic power generation devices using solar panels, wind power generation devices, and fuel cell power generation devices.

[0022] Distributed power source 10-1 includes distributed power source main unit 11-1 and PCS 12-1. Similarly, distributed power source 10-2 includes distributed power source main unit 11-2 and PCS 12-2, distributed power source 10-3 includes distributed power source main unit 11-3 and PCS 12-3, and distributed power source 10-4 includes distributed power source main unit 11-4 and PCS 12-4. Distributed power sources 11-1, 11-2, 11-3, and 11-4 (sometimes collectively referred to as distributed power source main unit 11) generate electric power.

[0023] PCS12-1, PCS12-2, PCS12-3, and PCS12-4 (sometimes referred to as PCS12) may be devices called PCSs (Power Conditioning Systems) or inverters. Each PCS12 may be a power converter that converts power generated by a corresponding distributed power supply main unit 11 into power according to the power grid 2. The microgrid may be a network in which PCSs 12 and loads 20 are randomly connected.

[0024] The load 20 may be a facility that consumes power. The load 20 is also called a consumer. A plurality of distributed power sources 10 and the loads 20 are connected by electric wires 3 to form a power system 2. The power system 2 may be a distribution system. The power system 2 may include a closed loop. Note that the resistance of the electric wires 3 of the power system 2 may be 1 / 10 or less of the reactance.

[0025] The distributed power management apparatus 100 manages a plurality of distributed power sources 10 in the power system 2. The distributed power management apparatus 100 acquires load information on the magnitudes of the loads 20-1, 20-2, 20-3, 20-4, 20-5, and 20-6. Based on the load information, the distributed power management apparatus 100 calculates a command value for the active power to be generated by at least some of the plurality of distributed power sources 10. This brings the frequency closer to the target value ωo.

[0026] 2 is a diagram showing the difference ωsync between the convergence value ω of the frequency and the target value ωo of the frequency in the power system 2. The difference ωsync is also called a synchronization frequency. The distributed power management apparatus 100 has a calculation unit 140 (described later). The calculation unit 140 calculates command values ​​for active power to be generated in at least some of the distributed power sources 10 based on load information so as to reduce the difference ωsync. Each calculated command value is transmitted to at least some of the distributed power sources 10.

[0027] 3 is a diagram showing an example of a schematic configuration of a distributed power management apparatus 100 according to the first embodiment of the present invention. The distributed power management apparatus 100 may be one or more computers. In one example, the distributed power management apparatus 100 is a DERMS (DER Management System).

[0028] The distributed power management apparatus 100 includes an acquisition unit 110 and a calculation unit 140. The distributed power management apparatus 100 may include a transmission unit 150. The acquisition unit 110 acquires load information about the size of the loads 20. In one example, the load information may be the power consumption of each load 20, or may be current and voltage for calculating the power consumption. The acquisition unit 110 may acquire the load information from a sensor 30. The sensor 30 may be a plurality of ammeters and voltmeters provided at nodes of the power system 2. The load information is provided to the calculation unit 140.

[0029] The calculation unit 140 calculates a command value for active power to be generated by at least some of the distributed power sources 10 based on the load information so as to reduce the difference ωsync between the convergence value ωc of the frequency and the target value ωo of the frequency in the power system 2. In this example, the calculation unit 140 calculates the command value for all of the multiple distributed power sources 10 that are under management.

[0030] The distributed power management apparatus 100 controls the frequency of the power grid 2 by a command value parameter P i The distributed power supply management apparatus 100 may calculate Pi from the grid information. The distributed power supply management apparatus 100 transmits the calculation result of Pi to each distributed power supply 10. Each distributed power supply 10 receives the calculation result of Pi.

[0031] Control for stabilizing the frequency of the power system 2 is given by the following equation. In one example, the total number of nodes in the power system 2 is assumed to be n. Of the total number of nodes, n, the number of loads 20 is assumed to be m. The number of PCSs 12 is nm. In the example shown in FIG. 1, m is 6, but n and m are not limited to these cases. ωi (t) is the frequency (angular frequency) of the output voltage of the i-th PCS 12. i and j are natural numbers from 0 to n. ωo is the target frequency (nominal frequency). The target frequency may be the commercial power frequency. In one example, the commercial power frequency may be 50 Hz in eastern Japan and 60 Hz in western Japan. n i is a positive constant called a droop coefficient, which may be given in advance.

[0032] P e,i is the active power supplied by the i-th node. The i-th node may be a PCS or a load. P e,i If P is a positive value, it indicates that the node is supplying power to other nodes (loads, PCS, batteries, etc.). e,i If is a negative value, it indicates that power is being supplied to the node from an external node (load, PCS, battery, etc.).

[0033] P i is the command value of the active power output for the i-th PCS 12. P i is also called a nominal active power set value. The calculation unit 140 calculates this command value P i By calculating and adjusting i (t) to approach the target frequency ωo. I is the set of nodes corresponding to PCS12 (inverter). L is the set of nodes corresponding to load 20. L、 ν I} is the set of all nodes. |ν|=n.

[0034] The phase dynamics of the inverter with pseudo-inertia is given by equation (1a). The power flow balance equation for the load is given by equation (1b).

number

[0035] In equation (1a), Mi is the inertia coefficient and Di is the damping coefficient.i is a preset positive parameter. The first term on the left side of equation (1a), i.e., the product of the second derivative of θi and Mi, is a pseudo-inertial term. The first term on the left side of equation (1a) represents the transient state of the PCS 12. When the PCS 12 is in a steady state, the first term on the left side of equation (1a) is zero.

[0036] When the power system 2 includes a plurality of PCSs 12 and a plurality of loads 20, P in equation (1a) e,i is the active power P of multiple PCS12s e,i is the sum of P in equation (1b). e,i is the active power P of multiple loads 20 e,i When the PCS12 is in a steady state, the effective power P e,i and the effective power P in equation (1b) e,i Therefore, when PCS12 is in a steady state, adding both sides of equation (1a) and equation (1b) gives P e,i can be eliminated, and the following equation (2) is obtained.

number

[0037] The calculation unit 140 reduces the numerator on the right side of equation (2) to make ωsync equal to or smaller than a predetermined value. Li and the active power P generated by the multiple distributed power sources 10 i The sum of ΣP i The calculation unit 140 calculates the command value so that the sum of the active powers consumed by the plurality of loads 20, ΣP Li and the sum of the active power generated by multiple distributed power sources 10, ΣP i The command value may be calculated so that the absolute value of ΣP is equal to Li is a negative value, and ΣP i is a positive value, so ΣP Li +ΣP i would ideally be 0.

[0038] The calculation unit 140 may calculate the command value so as to maximize the stability of the synchronous state in the power system 2. The synchronous state is a state in which the frequencies at all nodes (PCS 12, load 20) are aligned. The synchronous state is a state in which the phase difference between all nodes is maintained at a constant value. The stability of the synchronous state refers to the ability of the power system 2, which has temporarily become out of synchronous due to a disturbance, to recover to a synchronous state after the disturbance disappears. The calculation unit 140 may calculate the command value so as to maximize the convergence to the synchronous state with the highest stability. The calculation unit 140 may calculate the command value under the condition that the command value is equal to or greater than 0 and equal to or less than a predetermined planned value. The predetermined planned value is, for example, the rated capacity of the PCS 12.

[0039] 4A is a diagram illustrating an example of a schematic configuration of the calculation unit 140. The calculation unit 140 includes a vector generation unit 141 and a matrix generation unit 142. The calculation unit 140 may include a multiplication unit 143, an absolute value calculation unit 144, and a linear programming problem calculation unit 145.

[0040] The vector generation unit 141 generates a vector P. The components of the vector P are the load information P L,1 P L,2 P L,3 ···P L,m and the command values ​​P1, P2, P3, P n-m Includes:

number

[0041] The matrix generation unit 142 generates a connection matrix that represents the connection relationships between nodes in the power system 2. The nodes include a plurality of distributed power sources 10 and one or more loads 20. The nodes may refer to either the plurality of distributed power sources 10 or the one or more loads 20. The connection matrix generated by the matrix generation unit 142 is referred to as connection matrix B.

[0042] 4B is a diagram showing an example of the connection relationship between nodes in the power system 2. In FIG. 4B, n1 to n5 are nodes. Nodes n1 to n5 are connected by electric wires 3. In FIG. 4B, e1 to e4 indicate the direction of transmission in the electric wires 3. FIG. 4B shows an example in which there are five nodes and four electric wires 3.

[0043] FIG. 4C is an example of the connection matrix B when the connection relationship between nodes in the power system 2 is as shown in FIG. 4B. FIG. 4C is an example of the case where the rows of the connection matrix B are nodes and the columns are wires 3. When one wire 3 is connected to one node, the corresponding matrix element of the connection matrix B is "+1" or "-1." When one wire 3 is not connected to one node, the corresponding matrix element of the connection matrix B is "0."

[0044] When one node is connected to another node (for example, node n2 and node n3 in FIG. 4C) by one electric wire 3 (for example, electric wire 3-2 in FIG. 4C), the direction of transmission from the one node to the other node is defined as the + direction, and the direction of transmission opposite to the + direction is defined as the - direction. In this case, the matrix element corresponding to electric wire 3-2 and node n2 is "+1," and the matrix element corresponding to electric wire 3-2 and node n3 is "-1." The connection matrix B is a matrix in which all connection relationships between nodes in the power system 2 are expressed in terms of matrix elements.

[0045] The multiplication unit 143 (see FIG. 4A) multiplies the connection matrix B by the vector P (Equation 3). The calculation unit 140 (see FIG. 3) calculates the command value P based on the product of the connection matrix B and the vector P. i In the example of FIG. 4C, each row of the connection matrix B corresponds to each of the nodes n1 to n5, and each column of the connection matrix B corresponds to the electric wire 3 connecting the nodes n1 to n5. The vector P shown in equation (3) is a column vector. Therefore, in this example, the calculation unit 140 calculates the command value P based on the product of the transposed matrix of the connection matrix B and the vector P. i Calculate.

[0046] The absolute value calculation unit 144 calculates the absolute value (L2 norm) Γ of the product of the connection matrix B and the vector P. P tilde in equation (4a) is an n-dimensional vector. P tilde is defined by equation (4b).

number

[0047] If ωsync=0, then Γ corresponds to the absolute value (L2) of the product of the connection matrix B and the vector P.

number

[0048] The speed at which the phase angle θ of the PCS12 converges is an exponential function θ=e -λt It is known that Γ is given by the following equation. λ is a positive value. The larger λ is, the faster the phase angle θ converges. λ is a function of time. Here, λ and Γ have the following relationship: where c is a constant.

number

[0049] By reducing Γ, λ can be increased. As a result, the convergence of the phase angle θ becomes faster. When Γ is at its minimum value, the convergence of the phase angle θ becomes fastest. The calculation unit 140 calculates the command value P i may be calculated.

[0050] The calculation unit 140 may calculate a linear programming problem (optimization problem). In this example, the linear programming problem is a problem of calculating the sum of active power consumed by one or more loads 20, ΣP Li and the sum of the active power generated by the multiple distributed power sources 10, ΣP i and the command value P i is greater than or equal to 0 and the predetermined planned value P imaxThe constraint (st) is as follows: In this example, the linear programming problem has the objective function of minimizing Γ in equation (5).

number

[0051] 5 is a flowchart showing an example of a management method according to the first embodiment of the present invention. The management method manages a plurality of distributed power sources 10 in a power system 2 including the plurality of distributed power sources 10 and one or more loads 20. The acquisition unit 110 acquires load information about the magnitude of the load (step S10). The load information may be the power consumption of each load 20.

[0052] The calculation unit 140 calculates a command value P of active power to be generated by at least some of the distributed power sources 10 based on the load information so that the difference ωsync between the convergence value of the frequency in the power system 2 and the target value of the frequency becomes small. i (Step S30). The transmission unit 150 calculates the command value P i to at least some of the distributed power sources 10 (step S40). The distributed power management apparatus 100 determines whether the difference ωsync between the frequency convergence value ω and the target value ωo is equal to or less than a predetermined value (step S50). If the difference ωsync between the frequency convergence value ω and the target value ωo is greater than the predetermined value (step S50: NO), the distributed power management apparatus 100 repeats the following steps: calculation of a command value Pi by the calculation unit 140 (step S30), transmission of the calculated command value Pi to the distributed power sources 10 by the transmission unit 150 (step S40), acquisition of new load information by the acquisition unit 110 (step S10), and calculation of a new command value by the calculation unit 140 (step S30) until the difference ωsync between the frequency convergence value and the target frequency value becomes equal to or less than a predetermined value (step S50: YES).

[0053] 6 is a flowchart showing an example of the command value calculation process. FIG. 6 may be a subroutine of step S30 in FIG. 5. The vector generation unit 141 generates a vector P (step S200). The components of the vector P are the load information P L,1 P L,2 P L,3 ···P L,M and the command values ​​P1, P2, P3, P n-m Includes:

[0054] The matrix generation unit 142 generates a connection matrix B (see FIGS. 4B and 4C) that represents the connection relationships between nodes including a plurality of distributed power sources 10 and one or more loads 20 (step S202). i The step of calculating (step S30 in FIG. 5) is a step of calculating a command value Pi based on the product of the connection matrix B and the vector P. The multiplication unit 143 multiplies the connection matrix B by the vector P (Equation (3)) (step S204). The absolute value calculation unit 144 calculates the absolute value (L2)Γ of the product of the connection matrix B and the vector P (step S206).

[0055] The linear programming problem calculation unit 145 calculates a linear programming problem (optimization problem) (step S208). The linear programming problem calculation unit 145 sets the minimization of Γ under the constraint conditions as an objective function. Minimizing Γ corresponds to the phase angle θ converging to a stable state as quickly as possible. The linear programming problem is solved by solving the sum ΣP of active power consumed in one or more loads 20. Li and the sum of the active power generated by the multiple distributed power sources 10, ΣP i and the command value P i is greater than or equal to 0 and the predetermined planned value P imax The constraint is that the planned value P imax may be the rated capacity of the PCS 12. In this way, the linear programming problem calculation unit 145 calculates the linear programming problem (optimization problem) to obtain the command values ​​P1, P2, P3, P n-m Calculate.

[0056] According to the distributed power management device 100 of this embodiment, the distributed power management device 100 collects load information and the like, so the PCSs do not necessarily need to have a function for communicating with each other. Unlike conventional cases in which PCSs communicate with each other to solve nonlinear differential equations, the distributed power management device 100 can be applied even when the communication period is 1 second or more. For a microgrid that supplies power using distributed power sources 10, it is possible to restore a fluctuating system frequency to a target frequency. In particular, the distributed power management device 100 can set optimal command values ​​P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, P11, P12, P13, P14, P15, P16, P17, P18, P19, P20, P21, P22, P23, P24, P25, P26, P27, P28, P29, P30, P31, P32, P33, P34, P35, P36, P37, P38, P39, P40, P41, P42, P43, P44, P45, P46, P47, P48, P49, P49, P50, P51, P52, P53, P54, P55, P56, P57, P58, P59, P59, P60, P61, P62, P63, P64, P65, P66, P67, P68, P69, P69, P70, P71, P72, P73, P74, P75, P76, P77, P78, P79, P79, P80, P81, P82, P83, P84, P85, P86, P87, P88, P89, P90 n-m By transmitting this, the grid frequency can be quickly restored to the target frequency.

[0057] 7 is a diagram showing an example of a schematic configuration of a distributed power management apparatus 100 according to the second embodiment of the present invention. The calculation unit 140 in the distributed power management apparatus 100 according to the first embodiment calculates a command value P i The transmission unit 150 calculates the command value P i The distributed power management apparatus 100 in the second embodiment is not limited to this case. i If the number of distributed power sources 10 to which commands are to be sent increases, the time required for the transmission process by the distributed power management apparatus 100 tends to increase. If the required command frequency (interval) is 10 seconds, the upper limit of M(t) is limited to the number of devices that can be transmitted in 10 seconds.

[0058] The calculation unit 140 calculates a command value P of the active power to be generated by some of the distributed power sources 10 that it manages, rather than by all of the distributed power sources 10. i In this example, the distributed power management apparatus 100 includes a determination unit 160. The determination unit 160 determines the active power command value P i In the example shown in FIG. 8, the distributed generation 10 for which the active power command value P iThe distributed power supply management apparatus 100 in the second embodiment is similar to the distributed power supply management apparatus 100 in the first embodiment except for this point.

[0059] The command value P i By transmitting the command value P, it is possible to prevent a decrease in control performance due to a transmission delay in the distributed power source management apparatus 100. The determination unit 160 extracts the distributed power sources 10 that can significantly contribute to frequency recovery, and assigns the command value P i By transmitting the

[0060] When minimizing the absolute value Γ of the product of the incidence matrix B and the vector P, the auxiliary variable δ i (t) may be introduced. An auxiliary variable δ i (t) is the time when the i-th distributed power management apparatus 100 issues a command value P i If the parameter is a calculation (transmission) target, it may indicate 1, and if it is not a calculation (transmission) target, it may indicate 0. i When (t) is introduced, the calculation unit 140 calculates the following optimization problem.

number

[0061] M(t) is the command value P i This number may be determined by the determination unit 160. i When (t)=1, that is, when the i-th distributed generation 10 is in the command value P i If the calculation target (transmission target) is δ, it matches the constraint in equation (7). i When (t)=0, that is, when the i-th distributed generation 10 is in the command value P i If it is not subject to calculation (subject to transmission), P i (t)=P i It becomes (t-1).

[0062] Command value Pi The number M(t) of the distributed power sources 10 to be calculated may be determined by the determination unit 160 based on the load information. That is, the determination unit 160 may determine the number M(t) so as to cover the power consumption of the load 20. i When the number of distributed power sources 10 to which commands are to be sent increases, the time required for the distributed power management apparatus 100 to perform the transmission process tends to become longer. The upper limit of M(t) is limited to the number of devices that can be subjected to the transmission process, depending on the required command frequency (interval). Therefore, the determination unit 160 may determine the upper limit of the number M(t) based on the time required for the distributed power management apparatus 100 to perform the transmission process.

[0063] Instead of the determination unit 160 determining the number M, other information related to the number may be restricted, so that the command value P i For example, the determination unit 160 may calculate and transmit the command value P based on information on the rated capacity of each of the multiple distributed power sources 10 that it manages. i The EPA may determine a portion of the distributed generation that is subject to the calculation.

[0064] The decision unit 160 determines the command value P i Alternatively, the acquisition unit 110 may determine a portion of the distributed power sources 10 that are the targets of the calculation of the power consumption. The output of the plurality of distributed power sources 10 may be acquired from the power measurement unit 32 by the acquisition unit 110.

[0065] Fig. 8 is a flowchart showing an example of a management method according to the second embodiment of the present invention. In Fig. 8, the processes of steps S10, S40 and S50 are the same as those of the management method according to the first embodiment in Fig. 5. Therefore, detailed explanations will be omitted.

[0066] The determination unit 160 determines the command value P i In step S32, the determination unit 160 determines the number M(t) of the distributed power sources 10 for which the command value P iThe calculation unit 140 calculates the command value P of the active power to be generated by the distributed generation 10 determined by the determination unit 160. i is calculated (step S32).

[0067] In step S32, the calculation unit 140 and the determination unit 160 solve the mixed integer programming problem (MIP) of equation (8). The determination unit 160 extracts some of the distributed power sources 10 from the plurality of distributed power sources 10 so that the difference ωsync between the convergence value of the frequency in the power system 2 and the target value of the frequency becomes small. The calculation unit 140 determines the command value P i The calculation unit 140 calculates the sum of the active power consumed by one or more loads, ΣP Li and the active power ΣP generated by the multiple distributed power sources 10 i The command value P for the part of the distributed generation 10 extracted by the decision unit 160 is set so as to approach the sum of i may be calculated.

[0068] The calculation unit 140 calculates the sum of active power consumed by one or more loads, ΣP Li and the active power ΣP generated by the multiple distributed power sources 10 i The command value P for the part of the distributed generation 10 extracted by the determination unit 160 is set to be equal to the sum of i may be calculated.

[0069] The determination unit 160 may extract some of the distributed power sources 10 from the plurality of distributed power sources 10 so as to maximize the stability of the synchronous state in the power system 2. The calculation unit 140 calculates the command value P i The calculation unit 140 may calculate the command value P i may be calculated.

[0070] Fig. 9 is a flowchart showing another example of the management method according to the second embodiment of the present invention. In the example shown in Fig. 9, the acquisition unit 110 acquires information on the rated capacity of each of the multiple distributed power sources 10 that it manages (step S24). The rated capacity of each of the distributed power sources 10 may be acquired in advance.

[0071] In step S32, the calculation unit 140 and the determination unit 160 solve the mixed integer programming problem (MIP) of equation (8). However, instead of the constraint limiting the number M(t), a constraint that the total rated capacity is equal to or less than a predetermined value may be used. In this case, too, some distributed power sources 10 are extracted from the plurality of distributed power sources 10 so that the difference ωsync between the convergence value of the frequency in the power system 2 and the target frequency value is small.

[0072] Fig. 10 is a flowchart showing another example of the management method according to the second embodiment of the present invention. In the example shown in Fig. 10, the acquisition unit 110 acquires information on the outputs of the multiple distributed power sources 10 at a predetermined time (step S26).

[0073] A computer program may be provided to implement the management method of the present invention, which causes a computer to function as the distributed power management apparatus 100 of at least one of the first and second embodiments.

[0074] 11 shows an example of a computer 2200 in which aspects of the present invention may be embodied, in whole or in part. The computer 2200 according to this embodiment includes a CPU 2212, a RAM 2214, a graphics controller 2216, and a display device 2218, which are interconnected by a host controller 2210. The computer 2200 also includes input / output units such as a communication interface 2222, a hard disk drive 2224, a DVD-ROM drive 2226, and an IC card drive, which are connected to the host controller 2210 via an input / output controller 2220. The computer also includes legacy input / output units such as a ROM 2230 and a keyboard 2242, which are connected to the input / output controller 2220 via an input / output chip 2240.

[0075] The CPU 2212 operates according to programs stored in the ROM 2230 and RAM 2214, thereby controlling each unit. The graphics controller 2216 acquires image data generated by the CPU 2212 into a frame buffer or the like provided in the RAM 2214 or into the graphics controller 2216 itself, and causes the image data to be displayed on the display device 2218.

[0076] The communication interface 2222 communicates with other electronic devices via a network. The hard disk drive 2224 stores programs and data used by the CPU 2212 in the computer 2200. The DVD-ROM drive 2226 reads programs or data from the DVD-ROM 2201 and provides the programs or data to the hard disk drive 2224 via the RAM 2214. The IC card drive reads programs and data from an IC card and / or writes programs and data to an IC card.

[0077] The ROM 2230 stores therein a boot program or the like that is executed by the computer 2200 upon activation, and / or programs that depend on the hardware of the computer 2200. The input / output chip 2240 may also connect various input / output units to the input / output controller 2220 via a parallel port, a serial port, a keyboard port, a mouse port, etc.

[0078] The programs are provided by a computer-readable medium such as a DVD-ROM 2201 or an IC card. The programs are read from the computer-readable medium, installed in the hard disk drive 2224, RAM 2214, or ROM 2230, which are also examples of computer-readable media, and executed by the CPU 2212. Information processing described in these programs is read by the computer 2200, and brings about cooperation between the programs and the various types of hardware resources described above. An apparatus or method may be configured by realizing information manipulation or processing in accordance with the use of the computer 2200.

[0079] For example, when communication is performed between the computer 2200 and an external device, the CPU 2212 may execute a communication program loaded into the RAM 2214 and instruct the communication interface 2222 to perform communication processing based on the processing described in the communication program. Under the control of the CPU 2212, the communication interface 2222 reads transmission data stored in a transmission buffer processing area provided in the RAM 2214, the hard disk drive 2224, the DVD-ROM 2201, or a recording medium such as an IC card, and transmits the read transmission data to the network, or writes reception data received from the network to a reception buffer processing area or the like provided on the recording medium.

[0080] The CPU 2212 may also cause all or a necessary portion of a file or database stored on an external recording medium such as the hard disk drive 2224, the DVD-ROM drive 2226 (DVD-ROM 2201), an IC card, etc. to be read into the RAM 2214, and perform various types of processing on the data on the RAM 2214. The CPU 2212 then writes back the processed data to the external recording medium.

[0081] Various types of information, such as various types of programs, data, tables, and databases, may be stored on the recording medium and may undergo information processing. The CPU 2212 may perform various types of processing on data read from the RAM 2214, including various types of operations, information processing, conditional judgment, conditional branching, unconditional branching, information search / replacement, etc., as described throughout this disclosure and specified by the instruction sequences of the programs, and write the results back to the RAM 2214. The CPU 2212 may also search for information in a file, database, etc. on the recording medium. For example, if multiple entries each having an attribute value of a first attribute associated with an attribute value of a second attribute are stored on the recording medium, the CPU 2212 may search for an entry that matches a condition specified by the attribute value of the first attribute from among the multiple entries, read the attribute value of the second attribute stored in the entry, and thereby obtain the attribute value of the second attribute associated with the first attribute that satisfies a predetermined condition.

[0082] The above-described programs or software modules may be stored in a computer-readable medium on or near the computer 2200. A recording medium such as a hard disk or RAM provided in a server system connected to a dedicated communication network or the Internet can also be used as a computer-readable medium, thereby providing the programs to the computer 2200 via the network.

[0083] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the claims that such modifications and improvements can also be included within the technical scope of the present invention.

[0084] It should be noted that the execution order of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before," "prior to," etc., and that the processes can be performed in any order unless the output of a previous process is used in a subsequent process. Even if the operational flow in the claims, specifications, and drawings is described using "first," "next," etc. for convenience, this does not mean that the processes must be performed in this order. [Explanation of symbols]

[0085] 2 Power system, 3 Power line, 10 Distributed power source, 11 Distributed power source main unit, 12 PCS, 20 Load, 30 Sensor, 32 Power measurement unit, 100 Distributed power management device, 110 Acquisition unit, 140 Calculation unit, 141 Vector generation unit, 142 Matrix generation unit, 143 Multiplication unit, 144 Absolute value calculation unit, 145 Linear programming problem calculation unit, 150 Transmission unit, 160 Decision unit, 2200 Con Computer, 2201···DVD-ROM, 2210···Host controller, 2212···CPU, 2214···RAM, 2216···Graphics controller, 2218···Display device, 2220···Input / output controller, 2222···Communication interface, 2224···Hard disk drive, 2226···DVD-ROM drive, 2230···ROM, 2240···Input / output chip, 2242···Keyboard

Claims

1. 1. A distributed power management device that manages a plurality of distributed power sources in a power system including a plurality of distributed power sources and one or more loads, comprising: an acquisition unit that acquires load information regarding the magnitude of the load; a calculation unit that calculates a command value for active power to be generated by at least some of the distributed power sources based on the load information so that a difference between a convergence value of the frequency in the power grid and a target value of the frequency becomes small; and Equipped with The calculation unit a vector generating unit that generates a vector including the load information and the command value; a matrix generation unit that generates a connection matrix representing a connection relationship between the plurality of distributed power sources and a node including the one or more loads; and the calculation unit calculates the command value based on a product of the connection matrix and the vector. Distributed power management device.

2. The distributed power management device according to claim 1 , wherein the calculation unit calculates the command value based on an absolute value of a product of the connection matrix and the vector.

3. The distributed power management device according to claim 2 , wherein the calculation unit calculates the command value so that an absolute value of a product of the connection matrix and the vector is minimized.

4. 4. The distributed power management device according to claim 1, wherein when each row of the connection matrix corresponds to each of the nodes, each column of the connection matrix corresponds to an electric wire connecting the nodes, and the vector is a column vector, the calculation unit calculates the command value based on the product of a transpose of the connection matrix and the vector.

5. 5. The distributed power management device according to claim 1, wherein the calculation unit calculates the command value so that the sum of the active power consumed by the one or more loads approaches the sum of the active power generated by the plurality of distributed power sources.

6. 6. The distributed power management device according to claim 5, wherein the calculation unit calculates the command value so that a sum of active power consumed by the one or more loads is equal to a sum of active power generated by the plurality of distributed power sources.

7. The distributed power management apparatus according to claim 1 , wherein the calculation unit calculates the command value so as to maximize stability of a synchronous state in the power grid.

8. The distributed power management apparatus according to claim 7 , wherein the calculation unit calculates the command value so as to converge most quickly to the synchronous state with the highest stability.

9. 9. The distributed power management device of claim 1, wherein the calculation unit calculates a linear programming problem with constraints that a sum of active power consumed by the one or more loads is equal to a sum of active power generated by the plurality of distributed power sources and that the command value is greater than or equal to 0 and less than or equal to a predetermined planned value, and an objective function that minimizes the absolute value of the product of the connection matrix and the vector.

10. 10. The distributed power management device of claim 1, wherein the calculation of the command value by the calculation unit, the transmission of the calculated command value to at least some of the distributed power sources by a transmission unit, the acquisition of new load information by an acquisition unit, and the calculation of the new command value by the calculation unit are repeated until a difference between the convergence value of the frequency and the target value of the frequency becomes equal to or less than a predetermined value.

11. 1. A management method for managing a plurality of distributed power sources in a power system including a plurality of distributed power sources and one or more loads, the method comprising: an acquisition step in which one or more computers acquire load information regarding the magnitude of the load; a calculation step in which the one or more computers calculate, based on the load information, a command value for active power to be generated by at least some of the distributed power sources so that a difference between a convergence value of the frequency in the power grid and a target value of the frequency becomes small; Equipped with The calculation step comprises: a vector generation step of generating a vector including the load information and the command value; a matrix generation step of generating a connection matrix representing a connection relationship between the plurality of distributed power sources and a node including the one or more loads; and the calculation step is a step of calculating the command value based on a product of the connection matrix and the vector. Distributed power management methods.

12. A distributed power supply management program for causing a computer to function as the distributed power supply management apparatus according to any one of claims 1 to 10.

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