Optimization calculation method and system for dynamically adjusting tie line plan based on control section power flow

Abstract

The invention discloses an optimal calculation method and system for dynamically adjusting tie line plans based on control section power flow, and the method comprises the steps: obtaining tie line plans of a D day and a D-1 day, a clearing plan of a unit at the D-1 day, and the sensitivity of the unit to a tie line in a day-ahead market; calculating in-province and out-of-province components of the tie line on the D-1 day, the sum of out-of-province components of the tie line on the D day, out-of-province components of the tie line on the D day and a tie line plan after adjustment on the D day; the method comprises the following steps: acquiring tie line plans at a time period t and a time period t-1, a unit clearing plan at the time period t-1 and the sensitivity to tie lines in a real-time market, and calculating in-province and out-of-province components of the tie lines at the time period t-1, the sum of the out-of-province components of the tie lines at the time period t, out-of-province components of all the tie lines at the time period t and a tie line plan after adjustment at the time period t; the invention aims to eliminate the potential risk that the tie line section power flow is out-of-limit caused by unreasonable tie line plan distribution in the current power market, and improve the safety and stability of a power grid.

Description

TECHNICAL FIELD

[0001] The application relates to an optimization calculation method and system, in particular to an optimization calculation method and system for dynamically adjusting a tie-line plan based on control section power flow. BACKGROUND

[0002] In actual production of power system dispatching, determination of a tie-line plan usually depends on inter-provincial transaction results and a linear distribution principle of tie-line transmission capacity. However, the distribution method fails to fully consider actual generator unit output conditions related to the tie-line and lacks effective positive and negative feedback mechanisms. Therefore, the tie-line plan is relatively static in the adjustment and optimization process and cannot dynamically respond to changes in unit output, leading to the phenomenon that a tie-line section is prone to over-limit or obstruction. These problems not only interfere with the rules of market pricing but also may pose a threat to safe operation of the power grid, seriously affecting normal operation of the market.

[0003] In a day-ahead power market, although the tie-line plan formulated based on inter-provincial transaction results and tie-line transmission capacity can provide certain protection, its static nature limits its actual application effect in the optimization calculation process. Therefore, the plan cannot effectively participate in optimization calculation of generator unit output adjustment, leading to the fact that even with the flexibility of inter-provincial transactions, market benefits are not maximized. More critically, the static distribution method will lead to frequent start-stop of part of coal-fired units, increase unnecessary operation cost, waste social resources and reduce economic efficiency of the power market.

[0004] In summary, the current tie-line plan distribution method of the power market has many deficiencies and cannot effectively cope with challenges brought by changes in generator unit output, affecting optimized operation of the market. SUMMARY

[0005] The application aims to provide an optimization calculation method for dynamically adjusting a tie-line plan based on control section power flow to solve the problem of over-limit of section power flow caused by unreasonable distribution of the tie-line plan in the current power market, adapt to actual conditions in the power generation process, improve operation efficiency and safety of the power market, and on the other hand, provide an optimization calculation system for dynamically adjusting a tie-line plan based on control section power flow.

[0006] The optimization calculation method comprises the following steps:

[0007] Based on a day-ahead market, tie-line plans for D day and D-1 day, a D-1 day unit out-clear plan and unit sensitivity to the tie-line are acquired, D-1 day tie-line intra-provincial and inter-provincial components, D day tie-line inter-provincial component sum, D day tie-line inter-provincial component and the tie-line plan after adjustment of D day are calculated;

[0008] Based on the real-time market, obtain the tie line plans for time period t and time period t-1, the unit clearing plan for time period t-1, and the sensitivity of the units to the tie lines. Calculate the intra-provincial and inter-provincial components of the tie lines for time period t-1, the sum of the inter-provincial components of the tie lines for time period t, the inter-provincial components of each tie line for time period t, and the tie line plan after adjustment for time period t.

[0009] Based on the adjusted link plan for day D and the adjusted link plan for time period t, the link plan for time period t on day D is adjusted.

[0010] Preferably, the formula for calculating the intra-provincial and inter-provincial components of the D-1 day connection line is as follows:

[0011]

[0012] in, This indicates the provincial weight of each connecting line on D-1. This indicates the out-of-province weight of each connecting line on D-1. This indicates the province's crew clearance plan for D-1, SF i,tie This indicates the sensitivity of the generating units within the province to the tie line, where i represents the ID of the generating unit within the province, and P represents the output of the generating unit.

[0013] Preferably, the formula for calculating the sum of the provincial components of the D-day connecting line is as follows:

[0014]

[0015] in, This represents the total number of provincial components of the D-day connecting line. β represents the sum of the inter-provincial components of the connecting line during time period t on day D-1. t This indicates the scaling factor, TieP represents the planned size of the tie line, the subscript tie represents the tie line ID, and t represents the time period. This indicates the D-day connecting line plan. This indicates the D-1 day contact line plan. This represents the total number of provincial components of the connecting line during time period t on day D-1.

[0016] Preferably, the formulas for calculating the intra-provincial and inter-provincial components of the t-1 time period connecting line are as follows:

[0017]

[0018] in, This indicates the provincial component of the connecting line during the t-1 time period on day D. This indicates the out-of-province component of the connecting line during the t-1 time period on day D. This indicates the province's unit clearing plan for the t-1 period on day D, SF i,tie This indicates the sensitivity of the generating units within the province to the connecting lines. This indicates the planned connection line for the t-1 time period on day D.

[0019] Preferably, the formula for calculating the sum of the provincial components of the connecting line during time period t is as follows:

[0020]

[0021] in, This represents the total number of inter-provincial components of the connecting lines during the time period t on day D. α represents the sum of the inter-provincial components of the connecting line during time period t on day D-1. t This represents the proportionality coefficient.

[0022] Preferably, the adjusted tie-line plan formula is as follows:

[0023]

[0024] in, This indicates the planned connection line after the adjustment of the t-hour period on day D.

[0025] Preferably, the adjusted tie-line plan needs to satisfy the following relationship:

[0026]

[0027] in, and S represents the upper and lower limits of the cross-section, respectively. l This represents the set of connecting lines contained in section l.

[0028] The optimization computing system of the present invention includes:

[0029] The data acquisition module is used to acquire the tie-line plans for day-ahead market D-day and D-1-day, the unit clearing plan for day-1-day, and the sensitivity of units to tie-lines; and to acquire the tie-line plans for real-time market time periods t and t-1, the unit clearing plan for time period t-1, and the sensitivity of units to tie-lines.

[0030] The data calculation module is used to calculate the intra-provincial and inter-provincial components of the D-1 day connection line in the day-ahead market, the sum of the inter-provincial components of the D day connection line, the inter-provincial components of the D day connection line, and the connection line plan after adjustment on D day. It also calculates the intra-provincial and inter-provincial components of the connection line in the real-time market during the t-1 time period, the sum of the inter-provincial components of the connection line during the t time period, the inter-provincial components of each connection line during the t time period, and the connection line plan after adjustment during the t time period.

[0031] The adjustment module is used to adjust the connection line plan for the t-hour period on day D.

[0032] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: By dynamically adjusting the tie-line plan in the day-ahead market and the real-time market, and adjusting the tie-line plan in a timely manner according to the clearing results, the power flow of the cross sections related to the tie-line does not exceed the limit, thereby improving the overall operating efficiency and reliability of the power system and ensuring the safe operation of the power grid. Attached Figure Description

[0033] Figure 1 This is a schematic diagram illustrating the current market contact line plan adjustment process of this invention;

[0034] Figure 2 This is a schematic diagram of the real-time market contact line plan adjustment process of the present invention. Detailed Implementation

[0035] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0036] An optimized calculation method based on the dynamic adjustment of tie-line plans at control sections includes optimized calculations for both day-ahead and real-time markets.

[0037] The optimized calculation method for the recent adjustment of the dynamic connection line plan for the market control section includes the following steps:

[0038] S1, Obtain the D-day contact line plan D-1 Day Connection Plan

[0039] Where TieP represents the size of the tie line plan, the subscript tie represents the tie line ID, t represents the time period, which defaults to 1 to 96 (15 minutes per time period, the day-ahead calculation period is 24 hours, so it consists of 96 time periods), D represents the trading day, and D-1 represents the day before the trading day.

[0040] S2. Obtain the provincial unit clearing plan for day D-1. And the sensitivity of the unit within the province to the tie line SF i,tie .

[0041] Where i represents the unit ID within the province, and P represents the unit output.

[0042] S3. Calculate the provincial component of each connecting line on day D-1. D-1 Day: Provincial connections of various connecting lines The calculation formula is as follows:

[0043]

[0044] S4. Calculate the total sum of the out-of-province components of the D-day connecting line.

[0045] It is generally believed that the sum of the out-of-province components and the sum of the in-province components of the connecting line are proportional. The deviation in the connecting line plan between two days should be proportionally allocated to the sum of the out-of-province components and the sum of the in-province components of the connecting line according to their respective magnitudes. Therefore, the sum of the out-of-province components of the connecting line on day D-1 is added to the connecting line plan deviation on day D and day D-1, multiplied by the proportionality coefficient β. t The total number of provincial components of the D-day connecting line is obtained, and the proportionality coefficient β is obtained. t The calculation formula is as follows:

[0046]

[0047] in, This represents the total number of provincial components of the connecting line during time period t on day D-1.

[0048] and The calculation formula is as follows:

[0049]

[0050] The total weight of the D-day connecting line outside the province The calculation formula is:

[0051]

[0052] S5. Calculate the out-of-province component of each connecting line on day D.

[0053] With the power grid structure unchanged, the proportions of the out-of-province components of each tie line remain essentially constant. Therefore, the difference between the sums of the out-of-province components of the tie lines on the two days before and after are proportionally divided according to the magnitude of the out-of-province components of each tie line on day D-1, and then superimposed onto the out-of-province components of the tie lines on day D-1 to obtain the out-of-province components of the tie lines on day D. The calculation formula is as follows:

[0054]

[0055] S6. Calculate the tie-line plan after the adjustment on day D.

[0056] The D-day tie line plan needs to be adjusted according to the power flow at the tie line cross-section to ensure that the tie line cross-section does not exceed the limit. The calculation formula is as follows:

[0057]

[0058] A tie-line section typically consists of two or more tie-lines; therefore, the power flow is the superposition of tie-line plans within the section, denoted by S. l This represents the set of connecting lines contained in section l. and These represent the upper and lower limits of the cross-section, respectively.

[0059] The optimized calculation method for real-time market control section dynamic tie line planning adjustment includes the following steps:

[0060] S1, Obtain the contact line plan for day D, time period t. D-day t-1 time period connection plan

[0061] Where TieP represents the tie line plan size, the subscript tie represents the tie line ID, and t represents the time period. The real-time market defaults to 1 to 8 (15 minutes per time period, and the real-time calculation cycle is 2 hours, so it consists of 8 time periods). The real-time calculation is performed every 15 minutes. Therefore, for time period t, the tie line plan and unit output for time period t-1 are known quantities.

[0062] S2. Obtain the provincial unit clearing plan for the t-1 time period on day D. And the sensitivity of the unit within the province to the tie line SF i,tie .

[0063] S3. Calculate the provincial component of the connecting line during the t-1 time period on day D. And the inter-provincial component of the connecting line during the t-1 time period on day D. The calculation formula is as follows:

[0064]

[0065] S4. Calculate the total sum of the out-of-province components of the connecting line during the t-hour period on day D.

[0066] It is generally believed that the sum of the out-of-province components and the sum of the in-province components of the connecting line are proportional. The deviation of the connecting line plan between different time periods should be proportionally distributed between the sum of the out-of-province components and the sum of the in-province components of the connecting line according to their respective magnitudes. Therefore, the deviation of the sum of the out-of-province components of the connecting line at time t-1 on day D, plus the sum of the planned connecting line at time t on day D and time t-1, multiplied by the proportionality coefficient α, is calculated as follows: t The total number of inter-provincial components of the connecting line during the time period t on day D is obtained, with a proportionality coefficient α. t The calculation formula is as follows:

[0067]

[0068] in, This represents the total number of provincial components of the connecting line during the time period t-1 on day D. and The calculation method is as follows:

[0069]

[0070] The total number of inter-provincial connections during the D-day t-hour period. The calculation formula is:

[0071]

[0072] S5. Calculate the out-of-province components of each connecting line during the t-hour period on day D.

[0073] With the power grid structure unchanged, the proportion of power transmitted to other provinces by each tie line remains basically constant. Therefore, the difference between the sum of the tie line's power transmission to other provinces in time period t and time period t-1 is proportionally divided according to the magnitude of each tie line's power transmission to other provinces in time period t-1 of day D, and then superimposed on the tie line's power transmission to other provinces in time period t-1 of day D to obtain the tie line's power transmission to other provinces in time period t of day D. The calculation formula is as follows:

[0074]

[0075] S6. Calculate the connecting line plan after the adjustment of the t-day period on day D.

[0076] The tie line plan needs to be adjusted according to the power flow of the tie line cross-section to ensure that the tie line cross-section does not exceed the limit. The calculation formula is as follows:

[0077]

[0078] A tie-line section typically consists of two or more tie-lines; therefore, the power flow is the superposition of tie-line plans within the section, denoted by S. l This represents the set of connecting lines contained in section l. and These represent the upper and lower limits of the cross-section, respectively.

[0079] An optimization calculation system based on dynamic adjustment of tie line plans according to control section power flow includes:

[0080] The data acquisition module is used to acquire the tie-line plans for day-ahead market D-day and D-1-day, the unit clearing plan for day-1-day, and the sensitivity of units to tie-lines; and to acquire the tie-line plans for real-time market time periods t and t-1, the unit clearing plan for time period t-1, and the sensitivity of units to tie-lines.

[0081] The data calculation module is used to calculate the intra-provincial and inter-provincial components of the D-1 day connection line in the day-ahead market, the sum of the inter-provincial components of the D day connection line, the inter-provincial components of the D day connection line, and the connection line plan after adjustment on D day. It also calculates the intra-provincial and inter-provincial components of the connection line in the real-time market during the t-1 time period, the sum of the inter-provincial components of the connection line during the t time period, the inter-provincial components of each connection line during the t time period, and the connection line plan after adjustment during the t time period.

[0082] The adjustment module is used to adjust the connection line plan for the t-hour period on day D.

Claims

1. An optimization calculation method for tie-line planning based on dynamic adjustment of power flow at control sections, characterized in that, Includes the following steps: Based on the current market, obtain the tie line plans for D day and D-1 day, the unit clearing plan for D-1 day, and the sensitivity of the units to the tie line. Calculate the provincial and inter-provincial components of the tie line on D-1 day, the sum of the inter-provincial components of the tie line on D day, the inter-provincial components of the tie line on D day, and the tie line plan after adjustment on D day. Based on the real-time market, obtain the tie line plans for time period t and time period t-1, the unit clearing plan for time period t-1, and the sensitivity of the units to the tie lines. Calculate the intra-provincial and inter-provincial components of the tie lines for time period t-1, the sum of the inter-provincial components of the tie lines for time period t, the inter-provincial components of each tie line for time period t, and the tie line plan after adjustment for time period t. Based on the adjusted link plan for day D and the adjusted link plan for time period t, the link plan for time period t on day D is adjusted.

2. The optimization calculation method according to claim 1, characterized in that, The formulas for calculating the provincial and inter-provincial components of the D-1 day connection line are as follows: in, This indicates the provincial weight of each connecting line on D-1. This indicates the out-of-province weight of each connecting line on D-1. This indicates the province's crew clearance plan for D-1, SF i,tie This indicates the sensitivity of the generating units within the province to the tie line, where i represents the ID of the generating unit within the province, and P represents the output of the generating unit.

3. The optimization calculation method according to claim 1, characterized in that, The formula for calculating the sum of the provincial components of the D-day connecting line is as follows: in, This represents the total number of provincial components of the D-day connecting line. β represents the sum of the inter-provincial components of the connecting line during time period t on day D-1. t This indicates the scaling factor, TieP represents the planned size of the tie line, the subscript tie represents the tie line ID, and t represents the time period. This indicates the D-day connecting line plan. This indicates the D-1 day contact line plan. This represents the total number of provincial components of the connecting line during time period t on day D-1.

4. The optimization calculation method according to claim 1, characterized in that, The formulas for calculating the intra-provincial and inter-provincial components of the connecting line during the t-1 time period are as follows: in, This indicates the provincial component of the connecting line during the t-1 time period on day D. This indicates the out-of-province component of the connecting line during the t-1 time period on day D. This indicates the province's unit clearing plan for the t-1 period on day D, SF i,tie This indicates the sensitivity of the generating units within the province to the connecting lines. This indicates the planned connection line for the t-1 time period on day D.

5. The optimization calculation method according to claim 1, characterized in that, The formula for calculating the sum of the provincial components of the connecting line during time period t is as follows: in, This represents the total number of inter-provincial components of the connecting lines during the time period t on day D. α represents the sum of the inter-provincial components of the connecting line during time period t on day D-1. t This represents the proportionality coefficient.

6. The optimization calculation method according to claim 1, characterized in that, The adjusted formula for the connecting line plan is as follows: in, This indicates the planned connection line after the adjustment of the t-hour period on day D.

7. The optimization calculation method according to claim 6, characterized in that, The adjusted tie-line plan needs to satisfy the following relationship: in, and S represents the upper and lower limits of the cross-section, respectively. l This represents the set of connecting lines contained in section l.

8. An optimization calculation system for dynamic adjustment of tie-line plans based on control section power flow, characterized in that, include: The data acquisition module is used to acquire the tie-line plans for day-ahead market D-day and D-1-day, the unit clearing plan for day-1-day, and the sensitivity of units to tie-lines; and to acquire the tie-line plans for real-time market time periods t and t-1, the unit clearing plan for time period t-1, and the sensitivity of units to tie-lines. The data calculation module is used to calculate the intra-provincial and inter-provincial components of the D-1 day connection line in the day-ahead market, the sum of the inter-provincial components of the D day connection line, the inter-provincial components of the D day connection line, and the connection line plan after adjustment on D day. It also calculates the intra-provincial and inter-provincial components of the connection line in the real-time market during the t-1 time period, the sum of the inter-provincial components of the connection line during the t time period, the inter-provincial components of each connection line during the t time period, and the connection line plan after adjustment during the t time period. The adjustment module is used to adjust the connection line plan for the t-hour period on day D.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the optimization calculation method according to any one of claims 1 to 7.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the optimization calculation method according to any one of claims 1 to 7.

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