New energy field station distributed phase modifier capacity configuration method based on electrical parameter weighted proportion index

Abstract

The invention discloses a new energy field station distributed phase modifier capacity configuration method based on an electrical parameter weighted proportion index, and the method comprises the steps: S1, building a new energy grid-connected system simulation model according to the parameters of a new energy grid-connected system; s2, obtaining sample data based on the simulation model, and calculating the grey correlation degree of the electrical parameters and the transient overvoltage; s3, taking the grey correlation degree as a weight, and establishing an electrical parameter weighted proportion index alpha; and S4, configuring the distributed phase modifier by taking alpha as an index to obtain a final configuration scheme. The invention provides a new energy field station distributed phase modifier capacity configuration method which takes an overvoltage index as a constraint and is based on an electrical parameter weighted proportion index. Safe and stable operation of the new energy grid-connected system is guaranteed, and the configuration method has certain economical efficiency and effectiveness.

Description

Technical Field

[0001] The present invention belongs to the technical field of reactive power compensation for a new energy grid-connected system, and in particular relates to a method for configuring the capacity of a distributed phase-shifting device in a new energy station based on a weighted proportion index of electrical parameters. Background Art

[0002] At present, traditional synchronous machines are gradually being replaced by new energy power generation equipment, and the proportion of new energy output in the power grid is increasing. As the number of new energy power generation equipment increases, the system short-circuit ratio continues to decline, resulting in the gradual weakening of the stability of the power system, which poses a huge challenge to the operation of the power system.

[0003] Synchronous phase condensers, as a type of synchronous motor, can improve the voltage support capacity by adjusting the reactive power in the power system, thereby improving the stability of the power system. At present, there are many studies on the location of synchronous phase condensers, but there are few studies on the capacity configuration of synchronous phase condensers. Therefore, the present invention proposes a method for configuring the capacity of distributed phase condensers in new energy stations based on the weighted proportion index of electrical parameters. This method can have good economy and effectiveness under the premise of ensuring the transient stability of the new energy grid-connected system. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for configuring the capacity of distributed phase regulators in new energy stations based on the weighted proportion of electrical parameters, aiming at the configuration problem of distributed phase regulators in new energy stations. The transient stability of the new energy multi-station system is ensured, while having good economy and effectiveness.

[0005] In order to solve the above technical problems, the technical solution of the present invention is:

[0006] A method for configuring the capacity of distributed phase-shifting devices in new energy stations based on weighted proportion indicators of electrical parameters, comprising:

[0007] Step S1, establishing a new energy grid-connected system simulation model according to the new energy grid-connected system parameters;

[0008] Step S2, obtaining sample data based on the simulation model, and calculating the grey correlation between electrical parameters and transient overvoltage;

[0009] Step S3, using the grey correlation degree as the weight, establishing the electrical parameter weighted proportion index α;

[0010] Step S4: configure the distributed phase regulator using α as an indicator to obtain a final configuration solution.

[0011] Furthermore, in step S1, a simulation model of a new energy grid-connected system is established according to the parameters of the new energy grid-connected system, which specifically includes the following steps:

[0012] Obtain the impedance parameters of the new energy grid-connected system and the control parameters of the wind farm, and establish a new energy grid-connected system model;

[0013] Obtain the control parameters of the distributed phase regulator and establish a distributed phase regulator model.

[0014] In the step S2, sample data is obtained based on the simulation model, and the grey correlation between electrical parameters and transient overvoltage is calculated, which specifically includes the following steps:

[0015] Obtain data related to wind farm capacity and transient overvoltage, as well as data related to electrical distance and transient overvoltage;

[0016] The grey correlation between wind farm capacity and electrical distance and transient overvoltage is calculated respectively.

[0017] In the step S3, the grey correlation degree is used as the weight to establish the electrical parameter weighted proportion index α, which specifically includes the following steps:

[0018] The electrical parameters of each wind farm, namely, wind farm capacity and electrical distance, are obtained respectively;

[0019] Based on the electrical parameters of the wind farm and taking the grey correlation as the weight, the electrical parameter weighted proportion index α is established.

[0020] In step S4, the distributed phase regulator is configured with α as the index to obtain a final configuration scheme, which specifically includes the following steps:

[0021] Set a commutation failure fault at the receiving end of the new energy DC transmission system and run the system to observe whether there is a 35kV node with a transient voltage per unit value greater than 1.3;

[0022] Calculate the α value of each 35kV node when commutation failure occurs, and configure distributed phase regulators on the 35kV bus with the largest α value;

[0023] Repeat the above steps until the transient voltage per unit value of the 35kV node in the system is less than 1.3.

[0024] The specific expression of the electrical parameter weighted proportion index α is:

[0025]

[0026] Among them, γ1 and γ2 are the grey correlation between wind farm capacity and electrical distance, λ n It represents the proportion of the nth wind farm to the total wind farm capacity, It indicates the ratio of the electrical distance between the nth wind farm and the DC side to the total electrical distance.

[0027] λ n and The expression is:

[0028]

[0029] By adopting the above indicators, the present invention has the following beneficial effects:

[0030] The present invention firstly establishes a simulation model of a new energy grid-connected system according to the parameters of the new energy grid-connected system; secondly, the grey correlation between electrical parameters and transient overvoltage is calculated based on the simulation model, and the electrical parameter weighted proportion index α is established with the grey correlation as the weight; finally, the distributed phase regulator is configured with α as the index to obtain the final configuration scheme.

[0031] The present invention configures the distributed phase regulator based on the electrical parameter weighted proportion index α, which has certain advantages in terms of economy and effectiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a simulation model of the new energy grid-connected system of the present invention;

[0033] Figure 2 The distributed phase regulator capacity configuration flow chart of the present invention;

[0034] Figure 3 It is the simulation result image of the present invention (transient voltage image of three configuration methods). DETAILED DESCRIPTION

[0035] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments in conjunction with the accompanying drawings.

[0036] like Figure 1 As shown in the figure, the new energy grid-connected system consists of a sending-end system, a receiving-end system and n wind farms, where the sending-end AC system capacity is 4000MVA, and n is taken as 4. S1 = 1500MVA, S1:S2:S3:S4 = 10:9:8:7, and l1:l2:l3:l4 = 1:2:3:4.

[0037] like Figure 2 As shown in the figure, this example provides a distributed phase-converter capacity configuration method for a renewable energy grid-connected system, which includes:

[0038] Set a commutation failure fault at the receiving end of the new energy grid-connected system and run the system to observe whether there is a 35kV node with a transient voltage per unit value greater than 1.3;

[0039] Calculate the α value of each 35kV node when commutation failure occurs, and configure distributed phase regulators on the 35kV bus with the largest α value;

[0040] Run the simulation program of the new energy grid-connected system to observe whether there is a 35kV node with a transient voltage per unit value greater than 1.3; if so, repeat the above steps; if not, complete the distributed phase-converter configuration process.

[0041] like Figure 3 As shown in the figure, taking 1.3pu as the upper limit target value of overvoltage suppression, this example obtains transient voltage images of three schemes of configuring distributed phase-shifting devices using wind farm capacity, electrical distance and α as indicators, and compares the advantages and disadvantages of the three schemes, that is, the required capacity configured with wind farm capacity and electrical distance is 750Mvar, while only 700Mvar is needed to meet the transient voltage requirement when α is used as an indicator, which verifies the effectiveness and economy of the method proposed in the present invention.

Claims

1. A method for configuring the capacity of a distributed phase-shifting machine in a new energy station based on a weighted proportion index of electrical parameters, comprising: Step S1, establishing a new energy grid-connected system simulation model according to the new energy grid-connected system parameters; Step S2, obtaining sample data based on the simulation model, and calculating the grey correlation between electrical parameters and transient overvoltage; Step S3, using the grey correlation degree as the weight, establishing the electrical parameter weighted proportion index α; Step S4: configure the distributed phase regulator using α as an indicator to obtain a final configuration solution.

2. The method for configuring the capacity of distributed phase-shifting devices in new energy stations based on the weighted proportion index of electrical parameters according to claim 1 is characterized in that: In step S1, a simulation model of a new energy grid-connected system is established according to the parameters of the new energy grid-connected system, which specifically includes the following steps: Obtain the grid-connected parameters of the new energy grid-connected system, including line impedance parameters, wind farm control parameters, etc., and establish a simulation model of the new energy grid-connected system; Obtain the control parameters of the distributed phase regulator and establish a distributed phase regulator model.

3. The method for configuring the capacity of distributed phase-shifting devices in new energy stations based on the weighted proportion index of electrical parameters according to claim 1 is characterized in that: In the step S2, the grey correlation between the electrical parameters and the transient overvoltage is calculated, which specifically includes the following steps: Obtain data related to wind farm capacity and transient overvoltage based on the simulation model, as well as data related to electrical distance and transient overvoltage; The grey correlation between wind farm capacity, electrical distance and transient overvoltage is calculated respectively.

4. The method for configuring the capacity of distributed phase-shifting devices in new energy stations based on the weighted proportion index of electrical parameters according to claim 1 is characterized in that: In the step S3, the grey correlation degree is used as the weight to establish the electrical parameter weighted proportion index α, which specifically includes the following steps: The electrical parameters of each wind farm, namely, wind farm capacity and electrical distance, are obtained respectively; Based on the electrical parameters of the wind farm and taking the grey correlation as the weight, the electrical parameter weighted proportion index α is established.

5. The method for configuring the capacity of distributed phase-shifting devices in new energy stations based on the weighted proportion index of electrical parameters according to claim 1 is characterized in that: In step S4, the distributed phase regulator is configured with α as the index to obtain a final configuration scheme, which specifically includes the following steps: Set a commutation failure fault at the receiving end of the new energy grid-connected system and run the system to observe whether there is a 35kV node with a transient voltage per unit value greater than 1.3; Calculate the α value of each 35kV node when commutation failure occurs, and configure distributed phase regulators on the 35kV bus with the largest α value; Repeat the above steps until the transient voltage per unit value of all 35kV nodes in the system is less than 1.3.

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