KR20050028174A - System and method for evaluation of marginal loss factors for application to two way bidding pool(twbp) - Google Patents

Abstract

A system and a method for evaluating marginal loss factors to be applied to a TWBP(Two-Way Bidding Pool) are provided to calculate each power-flow value according to each bus based on power system data, and to calculate marginal loss factors in a reference generator based on the current values and the system data, thereby dealing with exact power transactions. A DB(505) stores system data of a power system. A power exchange server(503) calculates power-flow values of each bus, calculates marginal loss factors based on the power-flow values and the system data, calculates bidding prices for generator/sales business by applying the marginal loss factors, and determines spot market prices of power sales. A generator provider server(501) supplies bidding price information to the power exchange server(503), and receives information on generator provider bidding prices from the server(503). A sales provider server(507) supplies bidding price information on sales providers to the server(503), and receives information on sales provider bidding prices.

Description

System and Method for Evaluation of Marginal Loss Factors for Application to Two Way Bidding Pool (TWBP)}

The present invention relates to the calculation of the marginal transmission loss coefficient in the wholesale power market, and more particularly, an algorithm capable of analytically deriving the marginal transmission loss coefficient at the generator side and the load side center at the power system. The present invention relates to a method for calculating the marginal transmission loss factor for application to the bidirectional wholesale power market that can contribute to the development of software for Windows in the form of a GUI (Graphic User Interface).

In general, the power industry in the past, characterized by vertical integration, monopoly and regulation of power generation / transmission / distribution and sales, is transformed into a new paradigm of vertical division by sector, competition in sector, deregulation and active participation of private capital. Doing. In other words, the operation of the power system is based on an approach to minimize costs, but the competitive power market is changing in terms of profit or profit maximization of market participants (generators, transmission companies, sales operators).

To do this, it is necessary to accurately calculate the nodal price of the power system, and in order to apply such a marginal cost mechanism, the marginal power loss coefficients (MLFs) derived from the equation constraint of the power equation must be calculated. The marginal power loss factor is the sensitivity of the system loss function in a particular tidal current and is calculated from the amount of change in generation relative to the change in load. In addition, the marginal power loss coefficients (MLFs) have been reflected in the competitive power market in many countries in many ways because they lead to basic pricing decisions in the competitive power market.

In particular, Australia's NEMMCO derives marginal transmission loss coefficients using eigenvectors corresponding to eigenvalues, which are zeros of Jacobian matrices including the reference busbar. Also, in Sweden, each mothership is designated as a slack busline, and the bird's-eye calculation is performed to calculate the marginal power loss factor by using the entire mother bow.In Canada, the marginal power loss factor and the penalty factor are inversely used. To derive it.

However, the methodologies for deriving the load-centered marginal power loss coefficients are based on the assumption that Jacobian ignores changes in voltage magnitude despite changes in the voltage magnitude (ie reactive power change) of all buses in the power system. The load center limit transmission loss coefficient is derived using only the H matrix representing the change in active power with respect to the phase angle change in the matrix.

In Sweden, the generator-centered marginal power loss factor, which is defined as the amount of change in the generation of an arbitrary busbar with respect to the load increase of the entire system, is applied. The marginal transmission loss coefficient is derived. The above method has caused a problem that the computational burden is very large because it is necessary to perform tidal current calculation as much as the total number of buses in order to derive the generator-centered marginal transmission loss coefficient of all buses.

The present invention was created to solve the above problems, and an object of the present invention is to present a methodology that can be efficiently derived through the research and analysis of the existing methodology that can calculate the marginal power loss coefficient applied in the competitive power market. At the same time, several marginal transmission loss factor calculation methodologies are included so that practitioners and related parties who operate the power market can calculate the marginal transmission loss factor in real time or off-line to support the calculation of the marginal transmission loss factor appropriate for the realities of the Korean electricity market. The present invention provides a system and method for calculating the marginal transmission loss factor for the application to the bidirectional wholesale power market in which the built-in software can be built.

According to a first aspect of the present invention, there is provided a system for calculating a marginal power loss factor in a bidirectional wholesale power market, including: a database for storing system data of a power system; The tidal current value of each bus line of the power system is calculated on the basis of the grid data, the marginal transmission loss coefficient according to the total Jacobian equation is calculated on the basis of the result of the tidal flow value and the grid data, A power exchange server that calculates a bid price of a power generation business and a bid price of a sale business by applying the marginal transmission loss coefficient as a bid of a sale business, and determines a spot market price of power sales according to the calculation result; A power generation server that forms a network with the power exchange server and provides bid information of power generation companies to the power exchange server, and receives the power generation business bid price information from the power exchange server; And a sales operator server that forms a network with the power exchange server, provides bid information of sales operators to the power exchange server, and receives the sales business bid price information from the power exchange server.

In addition, the method of calculating the marginal transmission loss factor in the bidirectional wholesale power market according to the second aspect of the present invention for achieving the above object, calculates the tidal current value for each bus line of the power system based on the system data of the power system, Based on the result of the value and the system data, the marginal transmission loss factor of the total Jacobian calculation formula is calculated, and then the marginal transmission loss of the power exchange server that calculates the power sales price in the power market based on the marginal transmission loss coefficient. A method of calculating coefficients, the method comprising: a) designating a slack busbar as busbar-1 and setting a reference busbar as the slack busbar; b) calculating an amount of change in effective input power of the reference bus with respect to the magnitude and phase angle of the bus voltage, assuming that the voltage magnitude change of the power generation bus is zero from the entire Jacobian matrix used for calculating the tidal current value; And c) deriving the change amount of the effective input power from the generation of the change of the reference bus with respect to the load increase of any bus-i, wherein the load change of the remaining buses other than the bus-i is assumed to be zero (0). It is characterized in that the step of calculating the marginal transmission loss coefficient of the bus-i assuming that the power generation change of the other bus except the reference bus to zero (0).

The present invention having such features will be described in detail with reference to the accompanying drawings. 1 is a configuration diagram of a power system. First, in calculating the marginal power loss coefficient according to the present invention, it has a power system configuration as shown in FIG. 1, wherein the slack bus is designated as bus-1 and the reference bus at the time of calculating the marginal power loss coefficient is as the slack bus. do. In addition, the reactive power for the active power increment in any load bus-i is represented by Equation 1;

Set to. here, Is the increase in active power at any load bus-i, Is the increase in active power at any load bus-i, Is Is the power factor angle at mothership-i.

In the present invention, the power factor is not considered for a bus in which active power and reactive power are zero (0) or only reactive power exist in the bus-i of the power system before load increase in Equation 1 above. This is because the change of reactive power with respect to the increase of the actual active power cannot be taken into account. In addition, when calculating the marginal power loss coefficient, the tidal current calculation result of the power system is given.

Under such preconditions, the marginal power loss coefficient according to the present invention is calculated as follows.

First, when the reference busbar is designated as the slack busbar, the entire Jacobian matrix used for bird calculation is represented;

Same as here Is the effective / invalid input power increment at bus-i, Is the voltage phase angle and voltage magnitude increment in bus-i, where n is the overall parent of the power system, where n is to be.

Meanwhile, the effective input power of the reference bus, that is, the slack bus, For the bus voltage magnitude and phase angle for Equation 2;

, Where Is the amount of change in effective input power at the reference bus.

remind Denotes the change of the voltage magnitude in the power generation bus, and the change of the voltage magnitude can be ignored if the power generation voltage is kept constant. Therefore, mothership- from mothership-1 Voltage to ) Is treated as zero, and on the basis of this, the Jacobian matrix is expanded to be represented by Equation 3;

Represented by Is an effective input power increment vector of size (n-1) × 1, Reactive reactive power increment vector Is a busbar phase angle vector of size (n-1) × 1, Is the size Is the bus voltage magnitude vector, Is size (n-1) × (n-1) Jacobian matrix consisting of The size is (n-1) × ( )sign Jacobian matrix consisting of Is the size ( ) × (n-1) Jacobian matrix consisting of Is the size ( ) × ( )sign Jacobian matrix consisting of

Therefore, the effective input power change amount (Equation 2) ) Is represented by Equation 4;

It is expressed as here, Denotes the voltage magnitude and phase angle at bus-i, Is size (1) × (n-1) Is a matrix of The size is 1 × ( )sign Is a matrix of Is the effective input power at the reference bus.

On the other hand, taking the inverse of the Jacobian matrix of Equation 3 and substituting the equation 4 into Equation 5;

It is expressed as Further, when Equation 5 is expanded on the left side binomial;

Same as Where above Is the effective input power increment vector containing the reference bus of size n × 1. In addition, to facilitate the development of the limit transmission loss coefficient To If it is expressed as Equation 6;

It is expressed as

At this time, Speaking of equation (7);

here, Wow Is the change amount of the effective / effective power generation in bus-i, Wow Is the amount of change in the effective / invalid load on bus-i.

On the other hand, if Equation 7 is developed as follows: Equation 8;

Same as

At this time, the power generation bus of the power system And the load bus Assuming the game, Silver mothership Equivalent to the mother-n in. In this case, when Equation 8 is developed at the power factor of Equation 1, Equation 9;

Becomes Here, the marginal transmission loss factor is the amount of change in the generation amount of the reference bus (slack bus) with respect to the load increase of any bus-i, that is, Since the change in load of other buses except for bus-i is zero (0) and the change in power generation of the bus other than the reference bus, that is, bus-1, is zero (0), the marginal transmission loss factor of bus-i is Equation 10;

In the case of power generation bus (bus -1 to bus -n _G ),

For load bus (bus-n _{G + 1} to bus-n),

It is expressed as The marginal transmission loss coefficient thus derived is used to calculate the bid price and settlement of market participants. The present invention provides a computer simulation on a window based on the limit transmission loss coefficient, and the recommended specification is preferably an IBM-PC compatible computer with Intel Pentium IV or higher. Also, a 512MB or more memory, a VGA or more graphics card and monitor, a 10MB or more free hard disk space, an OS in which the framework according to the present invention is installed, a CD-ROM drive, a mouse, or the like may be appropriate. The operation description of the present invention refers to the calculation procedure of the limit transmission loss coefficient shown in FIG. 2 and the capture screen provided in FIG. 3.

First, as shown in FIG. 2, power market operation performance data for calculating the marginal power loss coefficient is loaded through step S201. The data corresponds to the power market operation performance data of versions 27, 28, and 29 of the current commercial program PSS / E, which indicates base values, bus data, load data, generator data, transformer data, and parallel capacitance data of the power system. . In (a) of FIG. 3, system data is loaded.

In step S203, it is determined whether the input of the data is normally performed, which is performed by the task and the display listed through a predetermined execution file. 3B is a screen showing input data of a power system and displays bus name, bus number, voltage size (VM), bus voltage phase angle (VA) information based on the data. Thereafter, in order to calculate the marginal power loss coefficient according to the present invention, the algal calculation result for each bus line is calculated through S205.

The results of the tidal current calculation are shown in (c) of FIG. 3, and the bus number, type (power bus or load bus), voltage size (VM), bus voltage phase angle (VA), and effective load amount of bus (PL) The reactive load (QL) and effective power generation (PG) values are listed along the bus. Thereafter, in step S207, the limit transmission loss coefficient is calculated, as shown in FIG. 3 (d), the load center limit transmission loss coefficient through Equation 11 and the generator center limit transmission proposed by the present inventors of the present invention. Generator center limit transmission loss factor (GFMLF (GGDF)) using GGDF using hybrid type algorithm proposed in the present invention taking into account loss factor (GFMLF), penalty factor, electrical distance, generator center using Kirschen algorithm Calculate the marginal transmission loss factor (GFMLF (Kirschen)) and generator-centered marginal transmission loss factor (GFMLF (Bialek)) using the Bialek algorithm, and compare the results of the marginal transmission loss coefficients for each methodology under specific tidal conditions. .

Here, since the marginal transmission loss coefficient has a unique calculation method for each country's electric power market, in addition to the marginal transmission loss coefficient according to the present invention, the generator-centered marginal transmission loss coefficient (GSMLF (Kirschen)) or It is possible to compare the marginal transmission loss coefficient (GSMLF (GGDF)) using the GGDF information or the generator-based marginal transmission loss coefficient (GSMLF (Bialek)) using the Bialek algorithm, so that the marginal transmission loss coefficients can be compared. . FIG. 3 (d) shows a screen shot of calculating a plurality of marginal power loss coefficients including penalty factors.

The calculation result of the limit transmission loss coefficient is stored in a predetermined memory (not shown) of the computer through step S209. The marginal transmission loss coefficient calculated as described above can be more accurately calculated in the spot market price (MCP), the feed amount of the power generation company, and the market participant's settlement, and the marginal transmission loss according to the present invention based on the power system of the specific bus. The difference between the bidding result and the market clearing price due to the coefficient and the marginal transmission loss coefficient according to the conventional method is as follows.

4 is a configuration diagram showing a 5 bus power system according to an embodiment of the present invention. As shown, an example of the generation of the bus-1, bus-3 and bus-5 and the distribution and sales of bus-2 and bus-4 are trading power through the power exchange. At this time, it is assumed that the power generation company and the distribution and sales company bid in two sections, and the bidding data for this is shown in Table 1.

Bidding data of power generation company bus Bid Segment 1 Bidding Segment 2 Bidding capacity [MW] Bid price [$ / MW] Bidding capacity [MW] Bid price [$ / MW] Gen-1 Bus-1 100 40 100 60 Gen-2 Bus-2 100 10 100 30 Gen-3 Bus-3 100 20 100 50

Bidding Data of Distribution and Sales Operators

bus Bid Segment 1 Bidding Segment 2 Bidding capacity [MW] Bid price [$ / MW] Bidding capacity [MW] Bid price [$ / MW] Load-1 Bus-2 150 70 200 55 Load-2 Bus-4 200 60 150 40

Here, selecting the bus-1 in Fig. 4 as the reference bus, and compares the limit transmission loss coefficient according to the present invention and the limit transmission loss coefficient according to the existing methodology is shown in Table 2 below.

Methodology of the Invention Existing Methodology Difference(%) Bus-1 1.0000000 1.0000000 0.000 Bus-2 1.0147486 1.0121534 0.260 Bus-3 0.9922736 0.9922973 0.002 Bus-4 1.0077946 1.0065231 0.127 Bus-5 0.9819454 0.9820946 0.015

As shown in Table 2, the largest difference of 0.260% occurs in bus-2 and the smallest difference of 0.002% occurs in bus-3. The difference in the marginal power loss coefficient of the power generation bus is because the marginal power loss coefficient is more accurately calculated by using the entire Jacobian used in the current tide calculation.

Based on the calculation result, the market surplus of the market participants can be derived by multiplying the spot market price by the marginal transmission loss coefficient. Therefore, the surplus that is generated by the marginal transmission loss coefficient derived by the marginal transmission loss coefficient of the present application It can be expected to be larger than by conventional methodology. Table 3 shows bid prices according to the above results.

Bidding Data of Generators bus Bid Segment 1 Bidding Segment 2 Bidding capacity [MW] * Bid Price [$ / MW] Bid price [$ / MW] Bidding capacity [MW] * Bid Price [$ / MW] Bid price [$ / MW] Gen-1 Bus-1 100 40.0000 40.0000 100 60.0000 60.0000 Gen-2 Bus-3 100 10.0779 10.0776 100 30.2336 30.2329 Gen-3 Bus-5 100 20.3677 20.3646 100 50.9193 50.9116

Bidding Data of Distribution and Sales Operators

bus Bid Segment 1 Bidding Segment 2 Bidding capacity [MW] * Bid Price [$ / MW] Bid price [$ / MW] Bidding capacity [MW] * Bid Price [$ / MW] Bid price [$ / MW] Load-1 Bus-2 150 68.9826 69.1594 200 54.2006 54.3396 Load-2 Bus-4 200 59.5359 59.6111 150 39.6906 39.7408

'*' Is the bid price derived from the marginal transmission loss coefficient for application in the present invention

As shown in Table 3, the difference in bid price is changed according to the loss change amount of load increase in the bus, taking into account the electrical distance between the specific bus and the reference bus. 5 shows a system of a wholesale power market based on a marginal transmission loss coefficient according to the present invention.

First, referring to the system configuration of the wholesale electric power market, a tidal current is calculated based on a database 505 for storing system data of a power system and system data stored in the database 505, and the tidal flow result value and the The power exchange server 503 for calculating the marginal transmission loss coefficient based on the grid data, and the power generation server 501, which is networked with the power exchange server 503 and receives a spot market price corresponding to the power generation energy output. And a sales operator server 501 which is networked with the power exchange server 503 and calculates a spot market price corresponding to the sales volume of generated energy based on the marginal transmission loss coefficient and then performs a bidding based thereon. Settlement surplus is based on the difference in the mutual spot market price calculated by the power generation company server 501 and the sales company server 507. It consists of a ball transmission business server 509 receives.

The system data indicates a power system base value of a bidding target, a parent bow, a load number, a generator number, a transformer number, and a parallel capacitance number. The calculation of the flow rate value and the limit transmission loss coefficient is a calculation module of the power exchange server 503. It is calculated by and has the result of Equation 10. At this time, the marginal transmission loss coefficient calculates each coefficient according to the power generation bus and the load bus, and based on the calculation result, the total power sales price corresponding to the electric power trading volume, the system data of the relevant power system, and the bidding information is calculated. Calculate through

At this time, the generator server 501 makes a bid according to the power generation capacity corresponding to each bus and generator of the power system, the seller server 507 makes a bid according to the consumption energy capacity corresponding to the bus. Proceed. The bidding data of the generator server 501 is provided in units of a predetermined time, including bidding information such as the minimum output possible tendency and the bid price of the generator, the output quantity and the price above and below the minimum output possible quantity, and the seller server. The bid data of 507 provides the power exchange server 503 with information to purchase power, including a load amount and price information, in predetermined time units.

The power exchange server 503 calculates a marginal transmission loss coefficient based on the grid data and the bird calculation result, and applies the calculation result to the bids presented by the power generation company server 501 and the sales company server 507. That is, the power exchange server 503 constructs an approximate market price system for each mother ship by using the marginal transmission loss coefficient, calculates an approximate selling price according to the bid, and provides the same. Accordingly, the power exchange server 503 provides a power transaction price that is proportional to the amount of load and the amount of power generated in real time.

On the other hand, since the marginal transmission loss coefficient calculated from the power exchange server 503 calculates the marginal transmission loss coefficient using the entire Jacobian used in the tide calculation, the result of the marginal transmission loss coefficient in the power generation bus according to the load change It is preferable that the difference between the bid of the sales business and the bid of the power generation business derived from the settlement surplus is transferred to the power transmission business, and replaced with the power line use of the power transmission business.

As described above, based on the marginal transmission loss coefficient applied in the present invention, the bid price of the market participants is multiplied by the marginal transmission loss coefficient for each mother / region by the actual measured power generation and power consumption of the power generation company and the distribution and sales operators. As the market participants derive their settlements, they will calculate the exact numerical value of the transmission loss and conduct electricity transactions based on it.

What has been described above is only one embodiment for the system and method for calculating the marginal power loss coefficient in the bidirectional wholesale power market according to the present invention, the present invention is not limited to the above-described embodiment, in the following claims As claimed, any person having ordinary skill in the art without departing from the gist of the present invention will have the technical spirit of the present invention to the extent that various modifications can be made.

In the present invention, the system and method for calculating the marginal transmission loss coefficient in the bidirectional wholesale power market according to the present invention calculates a tidal current value for each bus based on the grid data of the power system, and based on the tidal flow value and the grid data, The marginal transmission loss coefficient is calculated by the overall Jacobian matrix in Esau, and the power transmission in the electric power market is made more accurate according to the marginal transmission loss coefficient. Provide the effect.

In addition, by constructing an approximate market price system for each bus line using marginal transmission loss coefficients in a single price system that applies the same price for each bus bar, the price stability of the power market is obtained.

1 is a configuration diagram showing a power system.

2 is a flowchart for calculating a limit transmission loss coefficient according to the present invention.

3 is a computer screen shot showing the calculation process of the limit transmission loss coefficient according to the present invention.

4 is a five-bus case system diagram according to an embodiment of the present invention.

5 is a block diagram showing a network of power transactions using the marginal transmission loss coefficient of the present invention.

<Description of Symbols for Main Drawings>

501: power generation server 503: power exchange server

505: database 507: the seller server

509: Transmission Business Server

Claims (7)

A database for storing grid data of the power system; The tidal current value of each bus line of the power system is calculated on the basis of the grid data, the marginal transmission loss coefficient according to the total Jacobian equation is calculated on the basis of the result of the tidal flow value and the grid data, A power exchange server that calculates a bid price of a power generation business and a bid price of a sale business by applying the marginal transmission loss coefficient as a bid of a sale business, and determines a spot market price of power sales according to the calculation result; A power generation server that forms a network with the power exchange server and provides bid information of power generation companies to the power exchange server, and receives the power generation business bid price information from the power exchange server; And In a two-way wholesale power market characterized in that the network with the power exchange server to provide the bid information of the sales operators to the power exchange server, the sales server server receiving the sales bid price information from the power exchange server Limiting loss factor calculation system for the application of The method of claim 1, wherein when a difference occurs in each spot market price calculated by the generator server and the seller server, the surplus is transferred to the power transmission business. Limiting loss factor calculation system The system of claim 1, wherein the system data is a base value of a power system, which is a bidding target, a number of loads, a number of loads, a number of generators, a number of transformers, and a number of parallel capacitances. Loss Factor Estimation System. The method of claim 1, wherein the critical transmission loss coefficient in the power generation bus; A system for calculating the marginal transmission loss factor for application in the bidirectional wholesale electricity market, which is calculated according to the above. The method of claim 1, wherein the critical transmission loss coefficient is represented by the following equation in the load bus; A system for calculating the marginal transmission loss factor for application in the bidirectional wholesale electricity market, characterized by Based on the grid data of the power system, the tidal current value of each bus line of the power system is calculated, and based on the result of the tidal current value and the grid data, the marginal power loss coefficient according to the total Jacobian calculation formula is calculated, and then the marginal power loss. In the calculation method of the marginal transmission loss coefficient of the power exchange server for calculating the power sales price in the power market based on the coefficient, a) designating a slack busbar as busbar-1 and setting a reference busbar as the slack busbar; b) calculating an amount of change in effective input power of the reference bus with respect to the magnitude and phase angle of the bus voltage, assuming that the voltage magnitude change of the power generation bus is zero from the entire Jacobian matrix used for calculating the tidal current value; And c) The amount of change in the effective input power is derived from the generation change of the reference bus for the load increase of any bus-i, where the load change of the other bus except for the bus-i is assumed to be zero (0), the reference Calculating the marginal transmission loss coefficient of the bus-i by assuming that the generation variation of the other buses except for the mother bus is zero (0), the method of calculating the marginal transmission loss coefficient for the application in the bidirectional wholesale power market . 7. The method of claim 6, wherein the marginal power loss factor is used to calculate the spot market price (MCP), the amount of electricity supplied by power generation companies, and the settlement amount of market participants. How to calculate the marginal transmission loss factor.