Method for determining reactive compensation capacity of asynchronous power generation system

Abstract

The invention relates to the technical field of asynchronous power generation, and discloses an asynchronous power generation system reactive compensation capacity determination method, which comprises the following steps: acquiring each asynchronous generator in an asynchronous power generation system and generator basic information and transformer substation basic information corresponding to a network access transformer substation corresponding to the asynchronous generator; reactive power compensation capacity required by each asynchronous generator and reactive power compensation capacity required by a network access substation are calculated; according to the distance between each asynchronous generator and the corresponding network access substation, determining a planning path corresponding to a power transmission line connecting the asynchronous generator and the network access substation, and according to the planning path corresponding to the power transmission line, calculating reactive compensation capacity required by the power transmission line; and calculating the reactive compensation total capacity corresponding to the asynchronous power generation system based on a preset compensation total capacity calculation formula.

Description

Technical Field

[0001] The present invention relates to the technical field of asynchronous power generation, and in particular to a method for determining reactive power compensation capacity of an asynchronous power generation system. Background Art

[0002] In the power system, the management of reactive power is one of the key factors to ensure the stability and efficiency of the system. As a common power generation method, the asynchronous power generation system requires effective reactive power compensation to maintain the voltage level and power factor of the system in actual operation. Reactive power compensation can not only improve the power factor of the system and reduce transmission losses, but also improve the voltage quality and improve the overall performance and reliability of the system.

[0003] Traditional reactive power compensation methods usually only consider the reactive power demand of a single device or a local area, and lack comprehensive consideration of the entire system. This may lead to uneven distribution of reactive power compensation capacity, with some parts being overcompensated and others being undercompensated, thus affecting the overall performance of the system. Summary of the invention

[0004] One of the purposes of the present invention is to provide a method for determining the reactive compensation capacity of an asynchronous power generation system, which can achieve comprehensive consideration of the reactive compensation requirements of various devices in the asynchronous power generation system, greatly improve the calculation reliability and scientificity of the reactive compensation requirements of the entire asynchronous power generation system, and thus achieve efficient and stable operation of the system.

[0005] In order to achieve the above object, a method for determining reactive power compensation capacity of an asynchronous power generation system is provided, comprising the following steps:

[0006] S1. Obtain basic information of each asynchronous generator in the asynchronous power generation system, and basic information of the generator and the substation corresponding to the grid-connected substation corresponding to the asynchronous generator;

[0007] S2. Calculate the reactive power compensation capacity required by each asynchronous generator and the reactive power compensation capacity required by the grid-connected substation according to the basic information of the generator corresponding to each asynchronous generator and the basic information of the substation corresponding to the grid-connected substation;

[0008] S3. According to the distance between each asynchronous generator and the corresponding grid-connected substation, determine the planned path corresponding to the transmission line connecting the asynchronous generator and the grid-connected substation, and calculate the reactive power compensation capacity required for the transmission line according to the planned path corresponding to the transmission line;

[0009] S4. According to the reactive compensation capacity required by each asynchronous generator, the reactive compensation capacity required by the grid-connected substation and the reactive compensation capacity required by the transmission line, the total reactive compensation capacity corresponding to the asynchronous power generation system is calculated based on a preset total compensation capacity calculation formula.

[0010] Technical principles and effects of this scheme: In this scheme, first, basic information of the generators and basic information of the substations corresponding to the asynchronous generators in the asynchronous power generation system and the grid-connected substations corresponding to the asynchronous generators are obtained, and then the reactive compensation capacity required by each asynchronous generator and the reactive compensation capacity required by the grid-connected substation are calculated through the acquired basic information of the generators and the basic information of the substations, and the planned path corresponding to the transmission line connecting the asynchronous generator and the grid-connected substation is planned and determined in combination with the distance between each asynchronous generator and the corresponding grid-connected substation, so as to calculate the reactive compensation capacity required by the transmission line through the corresponding planned path, and finally, according to the reactive compensation capacity required by each asynchronous generator, the reactive compensation capacity required by the grid-connected substation and the reactive compensation capacity required by the transmission line, the total reactive compensation capacity corresponding to the asynchronous power generation system is calculated based on the preset total compensation capacity calculation formula.

[0011] 1. This solution not only takes into account the reactive power demand of each asynchronous generator, but also the reactive power demand of the grid-connected substation and transmission line, ensuring that the reactive power compensation of the entire system is comprehensive and balanced. By accurately calculating the reactive power compensation demand of each part, over-compensation or under-compensation can be avoided, thereby optimizing the allocation of resources and improving the overall efficiency of the system, that is, realizing comprehensive consideration of the reactive power compensation demand of each device in the asynchronous power generation system, greatly improving the calculation reliability and scientificity of the reactive power compensation demand of the entire asynchronous power generation system, and thus achieving efficient and stable operation of the system.

[0012] 2. By accurately calculating and implementing reactive power compensation, the power factor of the system can be effectively improved, the transmission loss of reactive power can be reduced, and the overall efficiency of the system can be improved.

[0013] Furthermore, the preset total compensation capacity calculation formula is:

[0014] Z=αX i +βY j +γS k +ε

[0015] In the formula, Z is the total reactive power compensation capacity corresponding to the asynchronous power generation system, X i is the total reactive power compensation capacity required by each asynchronous generator, Y j is the reactive power compensation capacity required by the grid-connected substation, S k is the reactive power compensation capacity required for the transmission line, α, β, γ are the corresponding weight values, and α, β, γ are dynamically changing. ε is the capacity increment corresponding to the total reactive power compensation capacity of all asynchronous generators in the asynchronous power generation system corresponding to the preset time period.

[0016] Beneficial effects: In this scheme, by dynamically adjusting the weight value, reactive power compensation resources can be reasonably allocated according to the actual operating conditions and system requirements to avoid over-compensation or under-compensation, thereby optimizing resource allocation and improving the overall efficiency of the system.

[0017] In some cases, such as extreme weather conditions, equipment failure, equipment loss or emergencies, the system may need additional reactive power compensation capacity to maintain stable operation. The preset capacity increment ε can be used as an emergency reserve to ensure that the system can still operate normally in these situations. With the reserved redundant capacity, the system can respond quickly when abnormal situations occur to ensure the stable operation of the system. For example, when a generator or substation fails, the system stability can be maintained by increasing the reactive power compensation capacity. The voltage fluctuation and instability caused by insufficient reactive power compensation can be reduced, thereby reducing the risk of equipment failure. This helps to improve the overall reliability and stability of the system.

[0018] Further, the method further includes S5, determining the size and setting position of the corresponding capacitor group and each capacitor in the capacitor group based on the calculated total reactive power compensation capacity corresponding to the asynchronous power generation system and a preset capacitor selection strategy;

[0019] The preset capacitor selection strategy is:

[0020] According to the total reactive power compensation capacity corresponding to the asynchronous power generation system, determine the total demand corresponding to the required capacitor bank;

[0021] According to the reactive power compensation capacity required by each asynchronous generator, the reactive power compensation capacity required by the grid-connected substation, and the reactive power compensation capacity required by the transmission line, the corresponding division ratio B is calculated, B = X i :Y j :S k , the total demand is divided according to the division ratio B to form a first demand Z1 corresponding to all asynchronous generators, a second demand Z2 corresponding to the grid-connected substations, and a third demand Z3 corresponding to the transmission lines;

[0022] According to the first demand Z1 corresponding to all asynchronous generators and the total reactive power compensation capacity required by each asynchronous generator, the first demand Z1 and the corresponding total reactive power compensation capacity X are determined. i The relationship between the values;

[0023] If Z1=X i , the first demand quantity is allocated according to the reactive power compensation capacity corresponding to each asynchronous generator;

[0024] If Z1>X i, the first demand quantity is allocated according to the reactive power compensation capacity corresponding to each asynchronous generator, and then the corresponding demand difference |Z1-X is calculated. i |; Obtain the historical reactive power compensation capacity corresponding to each asynchronous generator from the database, and calculate the performance value of each asynchronous generator based on the historical reactive power compensation capacity corresponding to each asynchronous generator and the preset asynchronous generator performance value calculation formula, and sort the performance values ​​of each asynchronous generator in ascending order to form a performance value sorting table;

[0025] The preset asynchronous generator performance value calculation formula is:

[0026]

[0027] Where E is the performance value of the asynchronous generator, Q(t) is the historical reactive power compensation capacity corresponding to a certain asynchronous generator at the historical time t, N is the total number of historical reactive power compensation capacities, and P is avg is the average active power corresponding to the asynchronous generator, W1 and W2 are the corresponding weighting coefficients;

[0028] According to the performance value ranking table, the asynchronous generator corresponding to the asynchronous generator performance value corresponding to the preset ranking is selected to allocate the demand difference. The smaller the asynchronous generator performance value corresponding to the asynchronous generator, the greater the demand allocated by the demand difference.

[0029] If Z1 <X i , then calculate the missing difference |X i -Z1|, dynamically adjust α according to the corresponding missing difference. The larger the missing difference, the larger the adjustment range of α, and re-execute S4.

[0030] Beneficial effects: In this scheme, by calculating the performance values ​​of asynchronous generators, generators with poor performance can be identified. Generators with smaller performance values ​​indicate that their reactive power compensation demand fluctuations in historical operation are large or their average reactive power compensation demand is high. These generators may need additional reactive power compensation in actual operation. Reasonable allocation of demand difference: According to the performance value sorting table, the demand difference |Z_1-X_i|) is allocated to the generator with smaller performance value. This ensures that reactive power compensation resources are allocated to the places where they are most needed, thereby improving the overall efficiency of the system.

[0031] In demand difference allocation, when Z1>X iWhen the demand difference is allocated according to the performance value sorting table, the generator with a smaller performance value will obtain more reactive power compensation capacity, which helps to prioritize the problem of generators with poor performance, thereby improving the performance of the entire system. Intelligent allocation based on performance value can quickly respond to system changes in a short time, ensuring that the system is always in the best condition, especially when the load fluctuates greatly.

[0032] When Z1 <X i When the system is running, the weight value is adjusted dynamically and the total reactive power compensation capacity is recalculated. This self-healing mechanism enables the system to automatically adjust when deviations occur, ensuring the stable operation of the system.

[0033] Furthermore, it also includes:

[0034] According to the basic information of each asynchronous generator, the generator model and the use time of each asynchronous generator are identified. According to the corresponding generator model, the corresponding generator model is identified in the historical database. If there is an identical generator model, the historical operation data corresponding to the historical asynchronous generator corresponding to the identical generator model is retrieved.

[0035] If there is no identical generator model, then based on the model similarity table, the historical operation data corresponding to the historical asynchronous generator with the highest similarity to the corresponding generator model is selected;

[0036] According to the service life of the asynchronous generator and the historical operation data of the selected historical asynchronous generator, the change degree of the reactive compensation capacity corresponding to the historical asynchronous generator within a preset time period after the corresponding generator service life is identified, and the capacity increment of the reactive compensation capacity corresponding to the corresponding asynchronous generator within the preset time period is determined according to the corresponding change degree, and the capacity increments corresponding to all asynchronous generators are summed up to form the capacity increment corresponding to the total reactive compensation capacity of all asynchronous generators in the asynchronous power generation system corresponding to the preset time period.

[0037] Beneficial effects: By retrieving the historical operating data of generators of the same or similar models, the reactive power compensation demand of the current generator in the future can be more accurately predicted, ensuring that reactive power compensation resources are reasonably allocated to where they are most needed, avoiding over-compensation or under-compensation. By analyzing the trend of reactive power compensation capacity changes in historical data, future demand changes can be more accurately estimated, thereby improving the prediction accuracy. By accurately predicting and reasonably allocating reactive power compensation capacity, voltage fluctuations can be effectively reduced and the voltage stability and reliability of the system can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1The present invention is a flowchart of a method for determining reactive power compensation capacity of an asynchronous power generation system in Embodiment 1 of the present invention. DETAILED DESCRIPTION

[0039] The following is further described in detail through specific implementation methods:

[0040] Embodiment 1

[0041] The method for determining the reactive power compensation capacity of asynchronous power generation system is basically as follows: Figure 1 As shown, the following steps are included:

[0042] S1. Obtain basic information of each asynchronous generator in the asynchronous power generation system and the corresponding grid-connected substation to which the asynchronous generator corresponds, as well as basic information of the substation; in this embodiment, the basic information of the generator includes the rated power, rated voltage, actual active power, actual power factor, generator model, generator usage time, and historical reactive power compensation capacity data of the asynchronous generator. Basic information of the substation includes substation capacity, voltage level, load characteristics, and historical reactive power compensation capacity data.

[0043] S2. Calculate the reactive power compensation capacity required by each asynchronous generator and the reactive power compensation capacity required by the grid-connected substation according to the basic information of the generator corresponding to each asynchronous generator and the basic information of the substation corresponding to the grid-connected substation;

[0044] S3. According to the distance between each asynchronous generator and the corresponding grid-connected substation, determine the planned path corresponding to the transmission line connecting the asynchronous generator and the grid-connected substation, and calculate the reactive compensation capacity required for the transmission line according to the planned path corresponding to the transmission line; in this embodiment, the distance between each asynchronous generator and the grid-connected substation is determined according to the geographic information system (GIS) or map data. Select the shortest path or the optimal path (considering factors such as terrain and environment), and use the existing optimization algorithm to plan the optimal path.

[0045] S4. According to the reactive compensation capacity required by each asynchronous generator, the reactive compensation capacity required by the grid-connected substation and the reactive compensation capacity required by the transmission line, the total reactive compensation capacity corresponding to the asynchronous power generation system is calculated based on a preset total compensation capacity calculation formula.

[0046] The preset total compensation capacity calculation formula is:

[0047] Z=αX i +βY j +γS k +ε

[0048] In the formula, Z is the total reactive power compensation capacity corresponding to the asynchronous power generation system, X iis the total reactive power compensation capacity required by each asynchronous generator, Y j is the reactive power compensation capacity required by the grid-connected substation, S k is the reactive power compensation capacity required for the transmission line, α, β, γ are the corresponding weight values, and α, β, γ are dynamically changing. ε is the capacity increment corresponding to the total reactive power compensation capacity of all asynchronous generators in the asynchronous power generation system corresponding to the preset time period.

[0049] Also includes:

[0050] According to the basic information of each asynchronous generator, the generator model and the use time of each asynchronous generator are identified. According to the corresponding generator model, the corresponding generator model is identified in the historical database. If there is an identical generator model, the historical operation data corresponding to the historical asynchronous generator corresponding to the identical generator model is retrieved.

[0051] If there is no identical generator model, the historical operating data corresponding to the historical asynchronous generator with the highest similarity to the corresponding generator model is selected based on the model similarity table; in this embodiment, the model similarity table is stored in the database, which records the similarity between each generator model and other generator models, as well as the historical operating data of the generator corresponding to each generator model.

[0052] According to the service life of the asynchronous generator and the historical operation data of the selected historical asynchronous generator, the change degree of the reactive compensation capacity corresponding to the historical asynchronous generator within a preset time period after the corresponding generator service life is identified, and the capacity increment of the reactive compensation capacity corresponding to the corresponding asynchronous generator within the preset time period is determined according to the corresponding change degree, and the capacity increments corresponding to all asynchronous generators are summed up to form the capacity increment corresponding to the total reactive compensation capacity of all asynchronous generators in the asynchronous power generation system corresponding to the preset time period.

[0053] The method further includes S5, determining the size and setting position of the corresponding capacitor group and each capacitor in the capacitor group according to the calculated total reactive power compensation capacity corresponding to the asynchronous power generation system and based on a preset capacitor selection strategy;

[0054] The preset capacitor selection strategy is:

[0055] According to the total reactive power compensation capacity corresponding to the asynchronous power generation system, determine the total demand corresponding to the required capacitor bank;

[0056] According to the reactive power compensation capacity required by each asynchronous generator, the reactive power compensation capacity required by the grid-connected substation, and the reactive power compensation capacity required by the transmission line, the corresponding division ratio B is calculated, B = X i :Y j :S k , the total demand is divided according to the division ratio B to form a first demand Z1 corresponding to all asynchronous generators, a second demand Z2 corresponding to the grid-connected substations, and a third demand Z3 corresponding to the transmission lines;

[0057] In this embodiment,

[0058] According to the first demand Z1 corresponding to all asynchronous generators and the total reactive power compensation capacity required by each asynchronous generator, the first demand Z1 and the corresponding total reactive power compensation capacity X are determined. i The relationship between the values;

[0059] If Z1=X i , the first demand quantity is allocated according to the reactive power compensation capacity corresponding to each asynchronous generator;

[0060] If Z1>X i , the first demand quantity is allocated according to the reactive power compensation capacity corresponding to each asynchronous generator, and then the corresponding demand difference |Z1-X is calculated. i |; Obtain the historical reactive power compensation capacity corresponding to each asynchronous generator from the database, and calculate the performance value of each asynchronous generator based on the historical reactive power compensation capacity corresponding to each asynchronous generator and the preset asynchronous generator performance value calculation formula, and sort the performance values ​​of each asynchronous generator in ascending order to form a performance value sorting table;

[0061] The preset asynchronous generator performance value calculation formula is:

[0062]

[0063] Where E is the performance value of the asynchronous generator, Q(t) is the historical reactive power compensation capacity corresponding to a certain asynchronous generator at the historical time t, N is the total number of historical reactive power compensation capacities, and P is avg is the average active power corresponding to the asynchronous generator, W1 and W2 are the corresponding weighting coefficients;

[0064] According to the performance value sorting table, the asynchronous generator corresponding to the asynchronous generator performance value corresponding to the preset ranking is selected to allocate the demand difference. The smaller the asynchronous generator performance value corresponding to the asynchronous generator, the greater the demand allocated by the demand difference. In this embodiment, the setting of the preset ranking is mainly related to the specific quantity in the performance value sorting table. Different data corresponds to different preset rankings.

[0065] If Z1 <X i , then calculate the missing difference |X i -Z1|, dynamically adjust α according to the corresponding missing difference. The larger the missing difference, the larger the adjustment range of α, and re-execute S4.

[0066] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is described too much here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field of the invention before the application date or priority date, can know all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A method for determining reactive power compensation capacity of an asynchronous power generation system, characterized in that: The following steps are involved: S1. Obtain basic information of each asynchronous generator in the asynchronous power generation system, and basic information of the generator and the substation corresponding to the grid-connected substation corresponding to the asynchronous generator; S2. Calculate the reactive power compensation capacity required by each asynchronous generator and the reactive power compensation capacity required by the grid-connected substation according to the basic information of the generator corresponding to each asynchronous generator and the basic information of the substation corresponding to the grid-connected substation; S3. According to the distance between each asynchronous generator and the corresponding grid-connected substation, determine the planned path corresponding to the transmission line connecting the asynchronous generator and the grid-connected substation, and calculate the reactive power compensation capacity required for the transmission line according to the planned path corresponding to the transmission line; S4. According to the reactive compensation capacity required by each asynchronous generator, the reactive compensation capacity required by the grid-connected substation and the reactive compensation capacity required by the transmission line, the total reactive compensation capacity corresponding to the asynchronous power generation system is calculated based on a preset total compensation capacity calculation formula.

2. The method for determining reactive power compensation capacity of an asynchronous power generation system according to claim 1, characterized in that: The preset total compensation capacity calculation formula is: Z=αX i +βY j +γS k +e In the formula, Z is the total reactive power compensation capacity corresponding to the asynchronous power generation system, X i is the total reactive power compensation capacity required by each asynchronous generator, Y j is the reactive power compensation capacity required by the grid-connected substation, S k is the reactive power compensation capacity required for the transmission line, α, β, γ are the corresponding weight values, and α, β, γ are dynamically changing. ε is the capacity increment corresponding to the total reactive power compensation capacity of the asynchronous power generation system corresponding to the preset time period.

3. The method for determining reactive power compensation capacity of an asynchronous power generation system according to claim 2, characterized in that: The method further includes S5, determining the size and setting position of the corresponding capacitor group and each capacitor in the capacitor group according to the calculated total reactive power compensation capacity corresponding to the asynchronous power generation system and based on a preset capacitor selection strategy; The preset capacitor selection strategy is: According to the total reactive power compensation capacity corresponding to the asynchronous power generation system, determine the total demand corresponding to the required capacitor bank; According to the reactive power compensation capacity required by each asynchronous generator, the reactive power compensation capacity required by the grid-connected substation, and the reactive power compensation capacity required by the transmission line, the corresponding division ratio B is calculated, B = X i :Y j :S k , the total demand is divided according to the division ratio B to form a first demand Z1 corresponding to all asynchronous generators, a second demand Z2 corresponding to the grid-connected substations, and a third demand Z3 corresponding to the transmission lines; According to the first demand Z1 corresponding to all asynchronous generators and the total reactive power compensation capacity required by each asynchronous generator, the first demand Z1 and the corresponding total reactive power compensation capacity X are determined. i The relationship between the values; If Z1=X i , the first demand quantity is allocated according to the reactive power compensation capacity corresponding to each asynchronous generator; If Z1>X i , the first demand quantity is allocated according to the reactive power compensation capacity corresponding to each asynchronous generator, and then the corresponding demand difference |Z1-Z is calculated. i |; Obtain the historical reactive power compensation capacity corresponding to each asynchronous generator from the database, and calculate the performance value of each asynchronous generator based on the historical reactive power compensation capacity corresponding to each asynchronous generator and the preset asynchronous generator performance value calculation formula, and sort the performance values ​​of each asynchronous generator in ascending order to form a performance value sorting table; The preset asynchronous generator performance value calculation formula is: Where E is the performance value of the asynchronous generator, Q(t) is the historical reactive power compensation capacity corresponding to a certain asynchronous generator at the historical time t, N is the total number of historical reactive power compensation capacities, and P is avg is the average active power corresponding to the asynchronous generator, W1 and W2 are the corresponding weighting coefficients; According to the performance value ranking table, the asynchronous generator corresponding to the asynchronous generator performance value corresponding to the preset ranking is selected to allocate the demand difference. The smaller the asynchronous generator performance value corresponding to the asynchronous generator, the greater the demand allocated by the demand difference. If Z1 <X i , then calculate the missing difference |X i -Z1|, dynamically adjust α according to the corresponding missing difference. The larger the missing difference, the larger the adjustment range of α, and re-execute S4.

4. The method for determining reactive power compensation capacity of an asynchronous power generation system according to claim 3, characterized in that: Also includes: According to the basic information of each asynchronous generator, the generator model and the use time of each asynchronous generator are identified. According to the corresponding generator model, the corresponding generator model is identified in the historical database. If there is an identical generator model, the historical operation data corresponding to the historical asynchronous generator corresponding to the identical generator model is retrieved. If there is no identical generator model, then based on the model similarity table, the historical operation data corresponding to the historical asynchronous generator with the highest similarity to the corresponding generator model is selected; According to the service life of the asynchronous generator and the historical operation data of the selected historical asynchronous generator, the change degree of the reactive compensation capacity corresponding to the historical asynchronous generator within a preset time period after the corresponding generator service life is identified, and the capacity increment of the reactive compensation capacity corresponding to the corresponding asynchronous generator within the preset time period is determined according to the corresponding change degree, and the capacity increments corresponding to all asynchronous generators are summed up to form the capacity increment corresponding to the total reactive compensation capacity of all asynchronous generators in the asynchronous power generation system corresponding to the preset time period.

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