WO2016006091A1

WO2016006091A1 - Power system analysis device and method

Info

Publication number: WO2016006091A1
Application number: PCT/JP2014/068530
Authority: WO
Inventors: 犬塚　達基; 俊之三宅
Original assignee: 株式会社日立製作所
Priority date: 2014-07-11
Filing date: 2014-07-11
Publication date: 2016-01-14

Abstract

If a change occurs in the configuration of a power system, it becomes necessary to rewrite a power equation that is a mathematical model, and load flow calculation cannot be continued in response to other power system structures (a mesh structure, a tree structure, or the like) or dynamic reconfiguration. Accordingly, the present invention is a power system analysis device that analyzes a power system configured on the basis of a plurality of nodes and branches that connect the nodes, said power system analysis device being characterized by the provision of: a means for calculating a load power that represents the power on a load side that is connected to the nodes; a means for calculating the complex voltage gradient of the branches on the basis of the load power; a means for calculating, on the basis of the complex voltage gradient, a correction amount for the complex voltage of an adjacent node that is connected to the nodes via the branches; and a means for calculating the correction amount for nodes within a predetermined range in the power system.

Description

Power system analysis apparatus and method

The present invention relates to a power system analysis apparatus and method for analyzing a power system.

The power system is operated with a balance between supply and demand, while various devices that generate and consume power perform their own operations. Conventionally, many power plants that generate electric power have been centrally installed and operated by electric power companies. Recently, however, distributed power sources such as solar power generation and wind power generation have begun to spread in order to utilize natural energy. The power generation amount of these distributed power sources varies depending on weather conditions. For example, the amount of solar radiation, wind direction, and wind speed cause changes in power generation. In addition, a large-capacity storage battery may be mounted on an electric vehicle or the like, and may be connected to the grid while changing the connection point, the connection time, the charge / discharge capacity, and the like. These fluctuation factors cause, for example, voltage fluctuations in the power system, and degrade the quality of power.
The power system is composed of a combination of L (inductance), C (capacitance), R (resistance), etc., and the state values of the power system are V (voltage), I (current), P (active power), Q (invalid) Power) and θ (phase). For these state values, a mathematical model can be described by equations such as power and voltage.

Simulators that perform power flow calculations for system analysis using equations related to such power systems are widely used. It is used to calculate the power flowing through the line by specifying state values such as input / output power of the load.

Although the literature is not cited, the power flow calculation method is known as a known technique. To analyze the power flow of the power grid, if you have voltage V, current I, admittance A, power S,

[Equation 1]
I = A ・ V
Multiply both sides by V and convert to unit of power S,

[Equation 2]
S = I ・ V = A ・ V ・ V
This is a nonlinear simultaneous equation and is called a power equation. By solving this equation, the power flow can be calculated.

Further, there is Patent Document 1 as a method for calculating a mathematical model of a power system by parallel calculation. The behavior of voltage and current is calculated by setting the time step for calculation and repeatedly calculating.

JP-A-9-107633

Since the power equation described above is a nonlinear simultaneous equation, a numerical calculation method such as the Newton-Raphson method is used. In order to solve the power equation by convergence calculation using the Newton-Raphson method, a matrix-type nonlinear power equation is prepared in advance. Therefore, if there is a change in the system configuration, it is necessary to rewrite the power equation, which is a mathematical model, and the power flow calculation cannot be continued in response to another structure (mesh structure, tree structure, etc.) or dynamic reconfiguration of the power system.

Patent Document 1 calculates a voltage / current waveform for the purpose of power system surge analysis, and is not suitable for calculating power flow.

In order to solve the above-described problem, the present invention provides a power system analysis device that analyzes a power system configured based on a plurality of nodes and a branch that connects the nodes, and includes power on a load side connected to the nodes. Means for calculating a load power indicative of a complex voltage gradient of the branch based on the load power, and a complex voltage of an adjacent node connected to the node via the branch based on the complex voltage gradient And means for calculating the correction amount for nodes within a predetermined range in the power system.

According to the present invention, since a power system schematic model is used in power flow calculation, power flow calculation can be started without preprocessing such as making a mathematical model in advance. , Tree structure, etc.) or dynamic flow reconstruction can be continued.

Diagram showing an example of system configuration Diagram showing an example of a two-dimensional array diagram model Diagram showing an example of a two-dimensional array diagram model Diagram showing voltage gradient between adjacent nodes flowchart Figure showing an example of setting adjacent nodes Figure showing an example of setting adjacent nodes Diagram showing power system scanning order Illustration of constraint function Diagram showing device configuration Diagram showing device configuration

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following examples show specific examples of the contents of the present invention, and the present invention is not limited to these examples, but by those skilled in the art within the scope of the technical idea disclosed in this specification. Various changes and modifications are possible.

Principle of Proposed Method Here, the relationship between the power system to be analyzed and the power flow calculation that simulates the power system is organized. First, there is a time relationship between online and offline. In the former online, the operation of the power system and the operation of power flow calculation are synchronized at the same time. Although there are factors such as the processing speed of the computer and the data transmission speed, generally speaking, online refers to the same time. System state values can be input from sensors provided in the power system and used for power flow calculations. On the other hand, the latter offline refers to an asynchronous operation that does not assume time sharing. The state value of the system from the power system is temporarily stored in a memory or the like and used as past data. Online and offline are properly used depending on the purpose of tidal current calculation. Off-line may be used for the purpose of evaluating and analyzing the characteristics of the system configuration in advance. On the other hand, if the purpose is to calculate a control command to a control device in the power system, an online form is obtained. The present invention described below can be applied to both online and offline.

Fig. 1 schematically shows the configuration of the power system. As basic elements constituting the power system, two types of nodes 101 (denoted as N in the figure) and branches 102 (denoted as Line in the figure) connecting the nodes are prepared. The node 101 is a system component such as a transformer, reactance, capacitance, etc., or a load installed by a consumer, a distributed power source using renewable energy. The branch 102 is a line connecting the nodes 101 and has characteristics such as line type and line impedance. The power system can be described as a relationship in which the node 101 and the branch 102 are connected. For example, a method for describing the connection relationship between the node 101 and the branch 102 with text data is easy to create and highly versatile, but preprocessing for replacing the text data with a mathematical model is essential.

On the other hand, the present invention arranges the node 101 and the branch 102 in a diagrammatic manner. The mathematical model will be called a graphical model. The graphical meaning is to describe a picture on a two-dimensional plane while maintaining the adjacent relationship between the node 101 and the branch 102. In other words, this corresponds to writing the elements that are adjacent to each other on the power system so that they are adjacent to each other in a two-dimensional array. When this two-dimensional array has a data structure prepared in a programming language, it is possible to refer to adjacent elements by changing the array index by one. Alternatively, when the two-dimensional array is a memory device, the elements in the adjacent relationship can be referred to by regular change of the memory address.

There are several ways to graphically represent a schematic model. As shown in FIG. 2, the node 101 is represented by a symbol □, the branch 102 is represented by a line connecting □, and information on the node 101 and the branch 102 can be written as attached information. As shown in FIG. 3, the node 101 and the branch 102 may be represented by the same symbol □. Or you may handle the intersection of a grid-like vertical and horizontal line as an element. Since the node 101 and the branch 102 have different functions, they may be distinguished from each other. As an adjacent relationship of the two-dimensional array, there are a method of diagonally up and down, left and right as viewed from a certain node 101, a method of four directions up and down, left and right as viewed from a certain node 101, and an appropriate one direction as viewed from a certain node How to do, etc. These are related to the calculation procedure described later.

Such a schematic model enables interactive data input with the operator. The above-described graphically represented screen is presented to the operator, and the operator can write the power system while viewing the screen, or can correct the data input in advance. Furthermore, the written screen can be used for a calculation procedure to be described later by treating it as a two-dimensional schematic model. Since the calculation results are made of the same two-dimensional array, the calculation results can be displayed on the screen superimposed on the input data. These input, calculation, two-dimensional array data used in the result stage, and means for storing the two-dimensional array data can be made in common.

As shown in FIG. 4, a node of interest is N ₃ , an adjacent node is N ₄ , and a branch connecting the two is Line ₃₄ . The voltage of each node is V ₃ and V ₄ , the impedance of the branch is Z ₃₄ , and the flowing current is I ₃₄ . The node N ₄ is connected to a load and consumes power S. In the initial state, all node voltages are Vs, and the current flowing through the branch is zero. By initializing the impedance of the branch as infinite, it does not contribute to the calculation of the power flow when there is no allocation of power system elements. These variables are expressed as complex numbers including phase. In the following description, the complex number format may not be specified for the sake of simplicity. FIG. 5 shows a flowchart. Since the power S is consumed at the node N ₄ , the current L ₄ flowing through the load is

[Equation 3]
L ₄ = S / V ₄
The branch current leading to node N ₄ is

[Equation 4]
I ₃₄ = L ₄
To pass this current between node N ₃ and node N ₄ from Ohm's law,

[Equation 5]
I ₃₄ = (V ₄ -V ₃ ) / Z ₃₄
Must.

In order to satisfy this relationship, it is necessary to make modifications so as to establish the relationship between the complex current and the complex voltage between the nodes. In other words, the voltage at node N ₃

[Equation 6]
V ₃ = V ₄ -I ₃₄・ Z ₃₄
You can correct it. Or it may share the magnitude of the voltage correction calculated in the node N ₃ and the node N ₄ adjacent.

However, this correction value is obtained only from the relationship between the node N ₃ and the node N ₄ , but in reality, other connected nodes must be considered. Further, when the correction value is directly used, the solution may oscillate or diverge. Therefore, a correction coefficient K is prepared so that the correction is gradually performed, and the following is set as a correction value.

[Equation 7]
V ₃ = (V ₄ -I ₃₄・ Z ₃₄ ) ・ K
The correction coefficient K is used as a numerical value of 0 <K <1 in the repeated calculation described below.

As shown in FIG. 6, the above basic calculation is obtained from the relationship between two adjacent nodes. This procedure may be extended to the relationship between adjacent nodes as shown in FIG. For example, the relationship between the complex voltage and the complex current is derived from the relationship between the node N of interest and the node adjacent to the node N.

In this case as well, the correction coefficient K is used as a numerical value of 0 <K <1 to gradually reflect the correction value in the repeated calculation described below.

In the present invention, based on the above procedure, the correction value is calculated by scanning all the combinations of nodes and branches constituting the system. FIG. 8 shows an example of the order in which the calculation proceeds. For example, the scanning order may be such that the upper left of the graphical model is the starting point and the lower right is the ending point, such as the scanning order of electron beams of a cathode ray tube. By initializing the impedance of grid points to which elements of the power system are not assigned to infinity, other nodes and branches are not affected, so scanning can be performed regularly without determining whether elements are assigned. become. Alternatively, for a region with a complicated system configuration, a large number of repeated calculations may be performed to help convergence. It is also possible to increase the speed by skipping scanning in the area where the power system is not arranged. Such density of power system arrangement may be determined in advance or may be determined in the course of repeated scanning.

繰り返す By repeating the procedure for scanning the above-described schematic model in an appropriate order, the correction amount gradually decreases and approaches a stable state. The situation gradually approaching the stable state is adjusted by the correction coefficient K described above. A method for setting the correction coefficient K will be described later.

There are two approaches to this iterative calculation. One obtains a stable solution by iterative calculation in order to calculate a state value at a certain fixed time. The other follows a stable solution by sequentially calculating repeatedly in synchronization with the advance of time. Alternatively, both are mixed and repeated calculation is performed at a certain time, then the time is advanced and repeated calculation is continued. In order to determine whether or not a stable solution has been obtained, a convergence determination is made using some threshold value. Or, without determining, the number of repeated calculations is set and the result is set as a stable solution.

In the configuration of the online device, iteratively proceeding with repeated calculations over time can be realized by appropriately combining the above repeated calculations. In the calculation of sequential tracking, there is a case where the time does not sufficiently converge at each time, but priority is given to tracking as time progresses. Or if it is the structure of an off-line apparatus, since it can calculate by stopping a time axis, it will suffice if it repeats calculation sufficiently at each time and it is made to converge.

As described above, the power flow calculation procedure of the present invention does not need to prepare a mathematical model of the power system in advance. Since iterative calculations are performed based on the schematic model, if there is a change in the system configuration over the course of the iterative calculation, there is a feature that enables dynamic reconfiguration that can be reflected in the calculation simply by changing the schematic model . There is no need to do any pre-processing before starting the tidal calculation. The calculation can be advanced by scanning the two-dimensional array prepared on the memory. This two-dimensional array can have the same data structure for the purpose of writing the configuration of the power system and the purpose of writing the result.

Even if the system is a mesh type structure, a loop type structure, a tree structure, or a mixture of these, there is no need to change the calculation procedure because there is no such distinction in the schematic model of the present invention.

Note that the above calculation range may be applied to the entire power system, or of course within a predetermined range.

Electric power diffusion The above principle will be described from another viewpoint. Look at the heat flow as an analogy. In the procedure for calculating the temperature distribution by the finite element method, the amount of heat flowing between adjacent elements is prepared as a differential equation or a difference equation and used as a basic unit of calculation. A stable solution is obtained by repeating the calculation of this basic unit over the entire structure.

It can be said that the procedure for obtaining a stable power solution according to the present invention by repetitive calculation reproduces the state in which power gradually diffuses, similar to heat diffusion. However, while the temperature is a scalar value, the power system is represented by a complex number. Elements constituting the power system include supply and consumption of power. The present invention interprets the flow of power to reach a stable solution through repeated trial and error. In the process of trial and error leading to a stable solution, the correction amount per time may be an appropriate minute amount that does not diverge.

Correction coefficient setting method, adaptive setting The correction coefficient K is prepared and the correction amount is calculated. This correction coefficient is set to 0 <K <1 as described above. The larger the value, the more likely the solution to diverge, and the smaller the value, the greater the number of iterative calculations to stabilize. The size can be variably set while observing the above restrictions. These tendencies may vary depending on the structure of the system. As the correction coefficient, the same numerical value may be used for the entire system, but it may be a different correction coefficient depending on the type and area of the system. Further, in combination with means for observing the degree of convergence, the numerical values may be switched in the process of repeated calculation. A numerical value is set by preparing means for determining and determining determination criteria such as stable convergence and quick convergence. When the degree of convergence depending on the system configuration is unknown, a numerical value for characteristic confirmation can be set, and the numerical value can be variably set based on the result. When the stability differs depending on the part or region of the system configuration, the correction coefficient may be set to a different value depending on the part or region of the system configuration.

Alternatively, the device may be configured such that the operator sets this correction factor via an interface. For example, an interface that allows the operator to explicitly adjust the correction coefficient can be prepared. This purpose is useful, for example, to help the operator learn the calculation algorithm.

Loads There are various characteristics of loads linked to the power system, such as linear and non-linear distinction, impedance load, constant power load, etc., and program-controlled load. Here, the impedance load is a device whose load power is determined based on Ohm's law, and corresponds to, for example, a lamp. The constant power load is a device that uses a semiconductor circuit to control the load power to be constant. For example, there is a corresponding device such as an air conditioner. In addition, the load for driving the semiconductor circuit by program control can have power characteristics that cannot be approximated by the simple mathematical model as described above. It is easy to reproduce the operation of the program control in the repeated calculation. Both loads consider the characteristics of active power and reactive power, that is, power factor. For this purpose, it is convenient to calculate in a complex form as described above. In the power flow calculation of the present invention, the node voltage is corrected in the process of repetitive calculation, so that the current flowing through the load changes due to voltage fluctuation. The recalculation of these load powers is executed in the repeated calculation.

Equipment that supplies power, such as solar power generation, can be regarded as a load having a minus sign. Since the storage battery performs both consumption and supply, it can be regarded as a load that can be switched. Since both are DC power supplies, conversion by an inverter is indispensable for connecting to an AC system. For example, a device called PCS (Power Conditioning System) may have control functions such as control of power factor (active power and reactive power) and suppression of power supply in addition to the inverter function. If these operation contents are known, it is easy to incorporate them into the power flow calculation procedure of the present invention.

Transformer
The voltage used in the power system is called a voltage class. In the power transmission system, a high voltage is used to reduce power loss due to the line, and in the power distribution system, a low voltage suitable for supplying to general consumers is used. Transformers are used to convert these voltages. The transformer is a device that performs voltage conversion using a ratio of the number of windings on the primary side and the secondary side. In the present invention, the voltage conversion function of the transformer is assigned as a function of a node connected to the branch on the primary side and the secondary side. In the node, the primary side and the secondary side are discriminated and the winding ratio between the primary side and the secondary side is set in advance. The complex voltage and complex current of this node itself are set as the primary side, for example. And the complex voltage and complex current converted by the winding ratio are allocated to the branch connected to the secondary side. Thus, the node having the function of the transformer can see the converted complex voltage and complex current on the primary side and the secondary side, respectively.

Also, it is possible to incorporate a function for performing voltage conversion with a circuit configuration called a switching converter using a semiconductor circuit. A switching converter is configured by combining an inductance, a capacitance, a diode, and the like with a semiconductor switch that performs high-speed on / off. However, when paying attention to voltage conversion, it is not necessary to consider the semiconductor circuit and the high-speed switching operation.

Voltage control equipment Control equipment for the purpose of voltage stabilization is used in the power system. In addition to cases where individual devices operate independently, there are cases where control content is transmitted from a centralized management means. The operation of these control devices is simulated and incorporated into the power flow calculation.

∙ Since SVR is a kind of transformer, it can be handled in the same way as the above-mentioned transformer. However, the turns ratio can be changed by tap switching. An input means for the tap switching signal is prepared. Voltage control devices such as SVCs and storage batteries can be handled in the same way as loads connected to nodes. Both can be incorporated into the tidal current calculation by deciding the operation of the aircraft while observing the voltage and current in the process of repeated calculations.

Constraint function In the operation of the power system, control is performed to achieve a desired state. One of them is voltage, and if it is a distribution system, it is required to be within the range of 101 ± 6V. Similar voltage ranges are determined for other voltage classes.

In the present invention, in order to realize such a voltage range constraint, the present invention provides a voltage constraint function in the process of calculating the voltage of the node and branch. For the correction amount calculated when it is near the periphery of the voltage range, the correction amount is multiplied by a constraint function so that the correction amount is not directed to the outside of the voltage range. FIG. 9 shows an example of the constraint function. If the shape has a size of 0 around the voltage range, this constraint function works so as not to create a correction amount that goes outside the voltage range. Or it can be rephrased as an induction function because it works to induce voltage.

∙ The above constraint function or induction function can be determined in advance, and can be arbitrarily changed while observing the state of the system. Since the power flow calculation means stores the state value of the entire target system in a variable or some kind of memory, it goes without saying that the state at an arbitrary location can be observed. Furthermore, it is possible to prepare some evaluation function created by combining variables, and to switch the above-described constraint function or induction function while looking at the result of the evaluation function. The target value is a state value such as voltage, current, or power, or a tap setting value of a device including a tap switching unit.

Also, it is possible to switch the constraint function or the induction function as described above from the situation such as the time zone when the load on the customer during the day is large or the time when the supply is excessive at night, taking in the time factor.

This procedure can be used to calculate a control signal for voltage stabilization of the power system, such as setting a higher voltage or setting a lower voltage.

Three-phase unbalanced power systems are often configured as a set of three phases shifted in AC phase. On the other hand, in order to simply analyze the power flow of alternating current, it is often necessary to consider only one phase. One method applied to the polyphase is to assign one line to one phase, and the polyphase is described by combining single-phase lines. The other is to assign polyphase properties to one line and incorporate the polyphase calculation into a single line calculation procedure. The present invention can realize any configuration.

GUI
In the present invention, nodes and branches are arranged in a diagrammatic manner to advance calculation of power flow.
A graphical user interface can be used as a diagrammatic arrangement mechanism. An example is shown below.

A screen on which array elements as shown in FIG. 10 are arranged is prepared. The element □ is distinguished by a node and a branch, and both are arranged alternately. This figure shows the progress of the repeated calculation described by the mouse operation on the display screen 104 of the PC 103.
After preparing these input screens in advance, the nodes and branches are actually selected with a mouse, pen, or keyboard. The selected array element is assigned a device type, function, performance, etc. in configuring the power system. When it is not assigned, only selectable frameworks are shown or initial values are provided so as not to contribute to the system configuration. In order to improve the visual design and improve the efficiency of the operator, elements that do not contribute may be written.

Including the process of repeated calculation, display can be performed using the above-described array element format, and state values relating to the power system can be displayed. It is possible to confirm the state of convergence with the so-called “jiwajiwa”. However, this does not always indicate a transient response.
Thus, by displaying the power system input screen and the screen for displaying the result of power flow calculation in an overlapping manner, the relationship between the cause and the result can be displayed in an easily understandable manner.

The present invention can be used as a simulator for analyzing a power system. The present invention can also be used as a control device that generates a control signal for controlling an electric power system. When the present invention is used as a control device, various sensor data related to the power system can be collected and used in a calculation procedure. The control device can be applied to any configuration called a centralized type or a distributed type. Compare the collected sensor data with the simulator output according to the present invention, and correct the characteristics of the simulator of the present invention so as to reduce the error between the two.
It can be used as a so-called observer.

Speeding up by parallel computing Parallel programming or parallel processing by a multi-core processor is used to speed up computations. The processor format is not limited, but a general-purpose processor called CPU (Central Processing Unit), a many-core processor called GPU (Graphic Processing Unit, General Purpose Unit, etc.), etc. are used. As shown in FIG. 11, in general, there are many configurations in which the CPU 105 performs overall system processing such as OS management, and the GPU 106 is installed as an additional device of the system. The additional device equipped with the GPU 106 can be obtained as a general-purpose graphics board 109 or a dedicated parallel computing board. A two-dimensional array memory 107 for handling image data is provided. However, while image processing is targeted for scalar values in units of pixels, the power flow calculation of the present invention is based on complex numbers. Complex numbers can be treated as scalar values by decomposing them into real and imaginary parts. However, since operations involving complex number multiplication and division are associated with the real part and the imaginary part, they cannot be handled independently.

Next, an example of a parallel calculation method using the GPU 106 will be described. The nodes and branches of the power system are allocated to a two-dimensional array memory, and the device characteristics are written in the memory 107. Nodes and branches may be assigned as different variables in the same memory area. In any case, the operation is regularly executed by storing the adjacent nodes and the characteristics of the branch connecting them in a memory with regular addresses. The GPU 106 is characterized by including a plurality of arithmetic units, and the individual arithmetic units execute memory access and arithmetic operations in parallel, thereby realizing high-speed overall signal processing.

In the power flow calculation of the power system of the present invention, the characteristic data of the power system is graphically arranged in the memory 107. It becomes easy to assign a plurality of arithmetic units included in the GPU 106 to elements constituting the power system. A plurality of arithmetic units can perform parallel processing, which is effective in speeding up repeated calculations. The program for instructing the calculation procedure is described in the same manner as the image processing that handles pixel data, and the effect of parallel execution is obtained. Further, the graphics board 109 provided with the GPU 106 can execute parallel computation and screen display simultaneously. The memory 107 that stores the elements and status of the system configuration may be used in common for both purposes.

∙ To use the GPU 106, pay attention to the use of memory and the mechanism of data exchange with the CPU 105. There are several types of memory accessed by the GPU 106 with different speeds and capacities. It is desirable to store frequently accessed data in a fast memory.

Combination with thermal model Electric power can be replaced with other energy by unit conversion. For example, heat and power can be converted to units of joules and watts using the relational equation J = Ws. By interposing such unit conversion, the energy flowing through the devices and branches arranged at the nodes may be replaced with heat.
A primary side and a secondary side having different units as in the transformer described above are prepared. The primary side and the secondary side are distinguished from each other, power is taken into the primary side, and the secondary side has a function of heat diffusion (or consumption). Both perform energy conversion according to the conversion equation described above. The flow of electric power and heat can be calculated by performing energy conversion in the repeated calculation of the power flow calculation of the present invention.

Calculate by combining the heat energy consumed in a certain area or building and the power system that supplies it as a power flow.

101 Node 102 Branch 103 PC
104 Display screen 105 CPU
106 GUI
107 memory 108 hard disk 109 graphic board 110 input / output IF
111 processor 112 display 113 bus

Claims

In a power system analysis device that analyzes a power system configured based on a plurality of nodes and a branch connecting the nodes,
Means for calculating load power indicating load-side power connected to the node;
Means for calculating a complex voltage gradient of the branch based on the load power;
Means for calculating a correction amount of a complex voltage of an adjacent node connected to the node via the branch based on the complex voltage gradient;
Means for calculating the correction amount for nodes within a predetermined range in the power system;
A power system analysis device comprising:
In the electric power system analysis device according to claim 1,
The complex voltage gradient is calculated based on the complex current of the branch calculated based on the load power;
The power system analysis apparatus characterized in that the correction amount is calculated based on a difference between the complex voltage and an initial value of the adjacent node.
In the electric power system analysis device according to claim 1,
An electric power system analyzing apparatus that calculates a correction amount of the complex voltage of each of the adjacent node and the node based on the complex voltage gradient.
In the electric power system analysis device according to claim 1,
The power system analysis apparatus further comprising an interface for displaying the correction amount in a multi-layered manner together with configuration information or status information of the power system.
In the electric power system analysis device according to claim 1,
An electric power system analysis apparatus characterized in that the correction amount of an adjacent node different from the node connected to the adjacent node via a branch is calculated, and the scan is sequentially performed on the nodes within the predetermined range.
In the electric power system analysis device according to claim 5,
The power system analysis apparatus characterized by repeating the scan from the beginning after the scan is performed on nodes within the predetermined range until the correction amount at each node of the power system converges within a predetermined threshold.
In the electric power system analysis device according to claim 5,
The power system analysis apparatus characterized by repeating the scanning from the beginning for a predetermined number of times after the scanning is performed for nodes within the predetermined range.
In the electric power system analysis device according to claim 1,
The correction amount is a value obtained by taking a product of the complex voltage and a correction coefficient larger than 0 and smaller than 1.
In the electric power system analysis device according to claim 8,
The power system analysis apparatus, wherein the correction coefficient is set with a different value for each type or predetermined area of the power system.
In the electric power system analysis device according to claim 8,
The power system analysis apparatus characterized in that the correction coefficient is calculated using a constraint function for convergence within a specified voltage range in the power system.
In the electric power system analysis device according to claim 8,
An electric power system analyzing apparatus further comprising an interface capable of adjusting the correction coefficient.
In the electric power system analysis device according to claim 1,
After correcting the complex voltage with the correction amount, the load power is calculated again.
In the electric power system analysis device according to claim 1,
The node includes at least one of a transformer including an SVR or a converter, a voltage control device including an SVC or a storage battery.
In the electric power system analysis device according to claim 1,
Means for converting the calculated power information into other types of energy information including thermal information;
An electric power system analyzing apparatus further comprising an interface for displaying the energy information of the other format in combination with the power information.
In a power system analysis method for analyzing a power system configured based on a plurality of nodes and a branch connecting the nodes,
Calculating load power indicating load-side power connected to the node;
Calculating a complex voltage gradient of the branch based on the load power;
Calculating a correction amount of a complex voltage of an adjacent node connected to the node via the branch based on the complex voltage gradient;
Calculating the correction amount for nodes within a predetermined range in the power system;
A power system analysis method comprising: