A voltage regulation method for a multi-source power system

Abstract

The present invention discloses a voltage regulation method for a multi-source power system. The voltage regulation method ranks the priority of each output source participating in the system voltage regulation according to the reactive compensation margin index C1 for evaluating the reactive compensation margin capability of each output source, the response time index C2 for evaluating the response speed of each output source, and the carbon emission intensity index C3 for evaluating the carbon emission of each output source, and performs voltage regulation according to the priority; wherein the reactive compensation margin index and the response time evaluation index have a response time scale of seconds and milliseconds, which greatly shortens the transient time of voltage regulation, improves the voltage regulation capability of the multi-source system to cope with transient faults, avoids the occurrence of subsequent chain failures, and improves safety. Compared with the existing multi-source power system which often ignores the control of carbon emissions when participating in voltage regulation, the carbon emission intensity index in the voltage regulation method of the present invention can effectively optimize the carbon emissions of the voltage regulation process and improve the environmental protection of the voltage regulation process.

Description

Technical field:

[0001] The present invention belongs to the technical field of new energy grid-connected power generation, and relates to a voltage regulation method for a multi-source power system, which is suitable for voltage regulation of a multi-source power system including offshore wind power. Background technology:

[0002] With the increasing shortage of fossil energy and the proposed goal of "carbon peak and carbon neutrality", clean energy such as wind power and photovoltaics will gradually become an important part of the energy production side. Since the output of clean energy has certain volatility and randomness, in order to improve the adaptability of clean energy to the grid, the voltage regulation problem of multi-source systems containing clean energy has become one of the problems that need to be solved urgently.

[0003] At present, the multi-source power system does not consider the carbon emission problem in the voltage regulation process, which is not conducive to environmental protection. In addition, the scheduling time scale of the existing multi-source power system optimization scheduling method is relatively long, ranging from minutes to hours. In the face of instantaneous faults, the voltage cannot be adjusted in time, which is easy to cause subsequent chain failures or even large system collapse.

[0004] The output sources of a multi-source power system including offshore wind power generally include wind power, photovoltaic power, hydropower, and thermal power output sources, and the output of its output sources often has certain volatility and randomness. In the case of system voltage fluctuations, the response rate and margin of the reactive power output of wind power, photovoltaic power and other renewable energy sources in a multi-source power system including offshore wind power need to be used as an important basis for measuring the priority of renewable energy in participating in system voltage regulation. Secondly, the existing multi-source system often ignores the control of carbon emissions when participating in voltage regulation, causing certain damage to the environment and is not conducive to sustainable development. Therefore, how to optimize carbon emissions in the process of voltage regulation is also an important basis for each output source to participate in system voltage regulation.

[0005] In the context of vigorously developing renewable energy power generation, it is necessary to improve the grid-connected adaptability of renewable energy, enhance the support capacity of multi-source systems including offshore wind power for system voltage, and optimize the control of carbon emissions during the voltage regulation process of multi-source systems. Summary of the invention:

[0006] In order to solve the problems existing in the prior art, the present invention proposes a voltage regulation method for a multi-source power system, which takes into account the output volatility of each output source in the multi-source power system and the environmental protection of the voltage regulation process of the multi-source system, and sorts the priority of each output source participating in the voltage regulation in the multi-source power system, so as to effectively improve the system voltage stability under the premise of environmental protection.

[0007] The technical solution of the present invention is as follows:

[0008] A voltage regulation method for a multi-source power system, wherein the output sources of the multi-source power system include at least two of wind power, photovoltaic power, hydropower, and thermal power output sources, and the voltage regulation method comprises:

[0009] Real-time acquisition of the attenuation ΔP of the maximum active output of each output source participating in voltage regulation, the increase ΔQ of the maximum reactive output, the time Δt required to complete the reactive increase, and the carbon emission ΔV;

[0010] When the system voltage deviates from the reference value, the reactive power compensation margin index C1 for evaluating the reactive power compensation margin capability of each output source, the response time index C2 for evaluating the response speed of each output source, and the carbon emission intensity index C3 for evaluating the carbon emission of each output source are calculated;

[0011] Then, according to the above index, the priority of each output source participating in the system voltage regulation is sorted, and the voltage is regulated according to the priority;

[0012] The reactive power compensation margin index C1 is the ratio of the attenuation ΔP of the active power output of the output source participating in voltage regulation to the increase ΔQ of the reactive power output.

[0013] The response time evaluation index C2 is the ratio of the increase in reactive power output ΔQ of the output source participating in voltage regulation to the time Δt required to complete the reactive power increase.

[0014] The carbon emission intensity index C3 is the ratio of the carbon emission of the output source ΔV to the increase in reactive output ΔQ involved in voltage regulation.

[0015] Preferably, the attenuation amount ΔP of the maximum active output of each output source participating in voltage regulation is the difference between the current active output of each output source and the minimum active output;

[0016] The increase in the maximum reactive output ΔQ of each output source is the difference between the reactive output under the lowest active output state and the current reactive output;

[0017] The time Δt and carbon emission intensity ΔV required for each output source to complete reactive power generation are based on actual engineering experience.

[0018] Preferably, the priority of each output source participating in the system voltage regulation is sorted as follows:

[0019] Firstly, the relative weight coefficients of reactive power compensation margin index C1, response time index C2 and carbon emission intensity index C3 are obtained by using the analytic hierarchy process;

[0020] Then, the relative weight coefficient is corrected by using the entropy weight matrix method to obtain the comprehensive weight coefficients of the reactive power compensation margin index C1, the response time index C2 and the carbon emission intensity index C3;

[0021] Finally, according to the comprehensive weight coefficient, the extension matter-element comprehensive evaluation method is adopted to obtain the priority of each output source participating in the system voltage regulation.

[0022] Preferably, the method of using the hierarchical analysis method to obtain the relative weight coefficients of the reactive power compensation margin index C1, the response time index C2 and the carbon emission intensity index C3 includes the following specific steps:

[0023] Construct a comparison matrix A among the reactive power compensation margin index C1, the response time index C2 and the carbon emission intensity index C3, and set the initial value of each element in the comparison matrix A;

[0024] According to the initial value, the consistency index CI of the comparison matrix A is calculated, and the average random consistency index RI of the comparison matrix A is obtained, and then the consistency ratio CR of the comparison matrix A is calculated;

[0025] If the consistency ratio CR of the comparison matrix A is less than 0.1, the comparison matrix A is consistent, and each element in the eigenvector ω(A)=(a1, a2, a3) of the comparison matrix A is the relative weight coefficient of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index; otherwise, the initial value of each element in the comparison matrix A is reset, and the relative weight coefficient of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index is obtained according to the reset initial value according to the above method;

[0026] in,

[0027]

[0028] In the formula, λ max is the maximum eigenvalue of the comparison matrix A.

[0029] Preferably, the average random consistency index RI of the comparison matrix A is obtained from an average random consistency index table.

[0030] Preferably, the entropy weight matrix method is used to correct the relative weight coefficients to obtain the comprehensive weight coefficients of the reactive power compensation margin index C1, the response time index C2 and the carbon emission intensity index C3, including the following specific steps:

[0031] First, the comparison matrix A is normalized to obtain the normalized matrix B;

[0032] Then calculate the entropy weight matrix D = (d1, d2, d3) according to the following formula:

[0033]

[0034]

[0035] Where, d i is the i-th element in the entropy weight matrix D; x i is the intermediate variable; A ij is the element in the i-th row and j-th column of the comparison matrix A; B ij is the element in the i-th row and j-th column of the normalized matrix B;

[0036] Finally, the comprehensive weight matrix F is calculated according to the following formula. Each element in the comprehensive weight matrix F = (f1, f2, f3) is the comprehensive weight coefficient of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index C3:

[0037]

[0038] In the formula, f i is the i-th element in the comprehensive weight matrix F.

[0039] Preferably, the step of obtaining the priority of each output source participating in the system voltage regulation by using the extension matter-element comprehensive evaluation method according to the comprehensive weight coefficient comprises the following specific steps:

[0040] Firstly, the classic domain and the node domain are determined, and the priority of each output source participating in the system voltage regulation is divided into two levels: high priority P1 and low priority P2;

[0041] Among them, the classical domain is:

[0042]

[0043] The section domain is:

[0044]

[0045] In the above formula, R p is a 3D object element; R1 and R2 are R p The first and second sub-element of the substance; P is the priority of each output source participating in the system voltage regulation; P1 is a high priority; P2 is a low priority; N1, N2 and N3 are the dividing points corresponding to C1, C2 and C3 respectively;

[0046] Then, according to the established classic domain and section domain, the closeness of reactive compensation margin index C1, response time index C2 and carbon emission intensity index C3 of each output source to the high priority P1 and the closeness to the low priority P2 are obtained respectively;

[0047] Among them, the closeness m1, m2 and m3 of C1, C2 and C3 to the high priority P1 are:

[0048] m1=N1-C1 m2=C2-N2 m3=N3-C3

[0049] The closeness of C1, C2 and C3 to the low priority P2, h1, h2 and h3, are:

[0050] h1=C1-N1 h2=N2-C2 h3=C3-N3

[0051] Then calculate the comprehensive relevance K1 of each output source relative to the high priority and the comprehensive relevance K2 relative to the low priority according to the following formula, where:

[0052] The comprehensive relevance K1 relative to the high priority is:

[0053] K1=m1·f1+m2·f2+m3·f3

[0054] The comprehensive relevance K2 relative to the low priority is:

[0055] K2=h1·f1+h2·f2+h3·f3

[0056] Among them, f1, f2, and f3 are the elements in the comprehensive weight matrix F respectively;

[0057] If K1≥K2, the priority of the output source participating in the system voltage regulation is high priority; if K1<K2, the priority of the output source participating in the system voltage regulation is low priority.

[0058] Compared with the prior art, the present invention has the following beneficial effects:

[0059] The present invention provides a voltage regulation method for a multi-source power system. The voltage regulation method ranks the priority of each output source participating in the system voltage regulation according to the reactive compensation margin index C1 for evaluating the reactive compensation margin capability of each output source, the response time index C2 for evaluating the response speed of each output source, and the carbon emission intensity index C3 for evaluating the carbon emission of each output source, and performs voltage regulation according to the priority; wherein the reactive compensation margin index and the response time evaluation index have a response time scale of seconds and milliseconds, which greatly shortens the transient time of voltage regulation, improves the voltage regulation capability of the multi-source system to cope with transient faults, avoids the occurrence of subsequent chain failures, and improves safety. Compared with the existing multi-source power system which often ignores the control of carbon emissions when participating in voltage regulation, the carbon emission intensity index in the voltage regulation method of the present invention can effectively optimize the carbon emissions of the voltage regulation process and improve the environmental protection of the voltage regulation process. Description of the drawings:

[0060] Figure 1 It is a control flow chart of the present invention in an embodiment. Specific implementation method:

[0061] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is described in detail below in conjunction with the accompanying drawings and implementation examples. It should be understood that the specific implementation examples described herein are only used to explain the present invention and are not used to limit the invention.

[0062] Embodiment one:

[0063] In this example, a voltage regulation method for a multi-source power system is provided, wherein the output sources of the multi-source power system include at least two of wind power, photovoltaic power, hydropower, and thermal power output sources, such as Figure 1 As shown, the voltage regulation method includes:

[0064] Obtain in real time the attenuation of the maximum active output ΔP, the increase in the maximum reactive output ΔQ, the time Δt required to complete the reactive increase, and the carbon emissions ΔV of each output source participating in the voltage regulation;

[0065] When the system voltage deviates from the reference value, the reactive power compensation margin index C1 for evaluating the reactive power compensation margin capability of each output source, the response time index C2 for evaluating the response speed of each output source, and the carbon emission intensity index C3 for evaluating the carbon emission of each output source are calculated;

[0066] Then, according to the above index, the priority of each output source participating in the system voltage regulation is sorted, and the voltage regulation is performed in order of high to low priority, that is, the high-priority output source is first used to participate in the voltage regulation. If the reactive output meets the voltage regulation demand, the voltage regulation is terminated; otherwise, the low-priority output source is used to participate in the voltage regulation so that the reactive output meets the voltage regulation demand.

[0067] Among them, the reactive power compensation margin index C1 is the ratio of the attenuation ΔP of the active power output of the output source participating in voltage regulation to the increase ΔQ of the reactive power output. The attenuation ΔP of the maximum active output of each output source participating in voltage regulation is the difference between the current active output of each output source and the minimum active output;

[0068] The increase in the maximum reactive output of each output source, ΔQ, is the difference between the reactive output under the lowest active output state and the current reactive output;

[0069] The response time evaluation index C2 is the ratio of the increase in reactive power output ΔQ of the output source participating in voltage regulation to the time Δt required to complete the reactive power increase. The time Δt and carbon emission intensity ΔV required for each output source to complete reactive power generation are taken from actual engineering experience.

[0070] The carbon emission intensity index C3 is the ratio of the carbon emission of the output source ΔV to the increase in reactive power output ΔQ involved in voltage regulation.

[0071] Embodiment 2:

[0072] A further optional design of this example is that in this example, the priority of each output source participating in the system voltage regulation is sorted as follows:

[0073] Firstly, the relative weight coefficients of reactive power compensation margin index C1, response time index C2 and carbon emission intensity index C3 are obtained by using the analytic hierarchy process;

[0074] Then the entropy weight matrix method is used to correct the relative weight coefficients to obtain the comprehensive weight coefficients of reactive compensation margin index C1, response time index C2 and carbon emission intensity index C3;

[0075] Finally, according to the comprehensive weight coefficient, the extension matter-element comprehensive evaluation method is adopted to obtain the priority of each output source participating in the system voltage regulation.

[0076] Embodiment three:

[0077] A further optional design of this example is that in this example, the relative weight coefficients of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index C3 are obtained by using the hierarchical analysis method, including the following specific steps:

[0078] Construct a comparison matrix A among the reactive power compensation margin index C1, the response time index C2 and the carbon emission intensity index C3, and set the initial value of each element in the comparison matrix A;

[0079] According to the initial value, the consistency index CI of the comparison matrix A is calculated, and the average random consistency index RI of the comparison matrix A is obtained, and then the consistency ratio CR of the comparison matrix A is calculated;

[0080] If the consistency ratio CR of the comparison matrix A is less than 0.1, the comparison matrix A is consistent, and each element in the eigenvector ω(A)=(a1, a2, a3) of the comparison matrix A corresponds to the relative weight coefficient of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index C3, that is, a1 corresponds to C1, a2 corresponds to C2, and a3 corresponds to C3; otherwise, the initial value of each element in the comparison matrix A is reset, and the relative weight coefficient of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index is obtained according to the reset initial value according to the above method;

[0081] in,

[0082]

[0083] In the formula, λ max is the maximum eigenvalue of the comparison matrix A.

[0084] Embodiment four:

[0085] A further optional design of this example is that in this example, the average random consistency index RI of the comparison matrix A is obtained from an average random consistency index table.

[0086] Embodiment five:

[0087] A further optional design of this example is that: in this example, the entropy weight matrix method is used to correct the relative weight coefficients to obtain the comprehensive weight coefficients of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index C3, including the following specific steps:

[0088] First, the comparison matrix A is normalized to obtain the normalized matrix B;

[0089] Then calculate the entropy weight matrix D = (d1, d2, d3) according to the following formula:

[0090]

[0091]

[0092] Where, d i is the i-th element in the entropy weight matrix D; x i is the intermediate variable; A ij is the element in the i-th row and j-th column of the comparison matrix A; B ij is the element in the i-th row and j-th column of the normalized matrix B;

[0093] Finally, the comprehensive weight matrix F is calculated according to the following formula. Each element in the comprehensive weight matrix F = (f1, f2, f3) corresponds to the comprehensive weight coefficient of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index C3. f1 corresponds to C1, f2 corresponds to C2, and f3 corresponds to C3. Among them,

[0094]

[0095] In the formula, F i is the i-th element in the comprehensive weight matrix F.

[0096] Embodiment six:

[0097] A further optional design of this example is: In this example, according to the comprehensive weight coefficient, the extension matter-element comprehensive evaluation method is adopted to obtain the priority of each output source participating in the system voltage regulation, including the following specific steps:

[0098] Firstly, the classic domain and the node domain are determined, and the priority of each output source participating in the system voltage regulation is divided into two levels: high priority P1 and low priority P2;

[0099] Among them, the classical domain is:

[0100]

[0101] The section domain is:

[0102]

[0103] In the above formula, R p is a 3D object element; R1 and R2 are R p The first and second sub-element of the substance; P is the priority of each output source participating in the system voltage regulation; P1 is a high priority; P2 is a low priority; N1, N2 and N3 are the dividing points corresponding to C1, C2 and C3 respectively;

[0104] Then, according to the established classic domain and section domain, the closeness of reactive compensation margin index C1, response time index C2 and carbon emission intensity index C3 of each output source to the high priority P1 and the closeness to the low priority P2 are obtained respectively;

[0105] Among them, the closeness m1, m2 and m3 of C1, C2 and C3 to the high priority P1 are:

[0106] m1=N1-C1 m2=C2-N2 m3=N3-C3

[0107] The closeness h1, h2 and h3 of C1, C2 and C3 to the low priority P2 are:

[0108] h1=C1-N1 h2=N2-C2 h3=C3-N3

[0109] Then calculate the comprehensive relevance K1 of each output source relative to the high priority and the comprehensive relevance K2 relative to the low priority according to the following formula, where:

[0110] The comprehensive relevance K1 relative to the high priority is:

[0111] K1=m1·f1+m2·f2+m3·f3

[0112] The comprehensive relevance K2 relative to the low priority is:

[0113] K2=h1·f1+h2·f2+h3·f3

[0114] Among them, f1, f2, and f3 are the elements in the comprehensive weight matrix F respectively;

[0115] If K1≥K2, the priority of the output source participating in the system voltage regulation is high priority; if K1<K2, the priority of the output source participating in the system voltage regulation is low priority.

[0116] Application examples:

[0117] In this example, the voltage regulation method of the present invention is used to control the voltage regulation of a multi-source power system of an offshore wind power plant. The output sources of the power system include four types of output sources: wind power, photovoltaic power, hydropower, and thermal power. The voltage regulation method includes:

[0118] Obtain in real time the attenuation of the maximum active output ΔP, the increase in the maximum reactive output ΔQ, the time Δt required to complete the reactive increase, and the carbon emissions ΔV of each output source participating in the voltage regulation;

[0119] When the system voltage deviates from the reference value, the reactive compensation margin index C1 for evaluating the reactive compensation margin capability of each output source, the response time index C2 for evaluating the response speed of each output source, and the carbon emission intensity index C3 for evaluating the carbon emissions of each output source are calculated; wherein, the reactive compensation margin index C1 is the ratio of the attenuation ΔP of the active output of the output source participating in voltage regulation to the increase ΔQ of the reactive output,

[0120] The response time evaluation index C2 is the ratio of the increase in reactive power output ΔQ of the output source participating in voltage regulation to the time Δt required to complete the reactive power increase.

[0121] The carbon emission intensity index C3 is the ratio of the carbon emission of the output source ΔV to the increase in reactive power output ΔQ involved in voltage regulation.

[0122] The attenuation ΔP of the maximum active output of each output source participating in voltage regulation is the difference between the current active output of each output source and the minimum active output;

[0123] The increase in the maximum reactive output of each output source, ΔQ, is the difference between the reactive output under the lowest active output state and the current reactive output;

[0124] The time Δt and carbon emission intensity ΔV required for each output source to complete reactive power generation are taken from actual engineering experience.

[0125] Then, according to the above index, the priority of each output source participating in the system voltage regulation is sorted, and the voltage regulation is performed in order of priority from high to low, that is, the output source with high priority is used to participate in the voltage regulation first. If the reactive output meets the voltage regulation requirements, the voltage regulation is terminated; otherwise, the output source with low priority is used to participate in the voltage regulation so that the reactive output meets the voltage regulation requirements. Among them, the priority of each output source participating in the system voltage regulation is sorted according to the following method:

[0126] Firstly, the relative weight coefficients of reactive power compensation margin index C1, response time index C2 and carbon emission intensity index C3 are obtained by using the analytic hierarchy process, which includes the following specific steps:

[0127] A comparison matrix A among the reactive power compensation margin index C1, the response time index C2 and the carbon emission intensity index C3 is constructed, and the initial value of each element in the comparison matrix A is set, as shown in Table 1.

[0128] Table 1 Comparison matrix initial value table

[0129]

[0130]

[0131] The maximum eigenvalue λ of the contrast matrix A max (A) is 3, and the corresponding eigenvector ω(A) is [0.1482 0.28570.5717],

[0132] According to the above initial values, the consistency index CI of the comparison matrix A is calculated to be 0, and the average random consistency index RI of the comparison matrix A is obtained to be 0.58. The average random consistency index RI of the comparison matrix A is obtained from the average random consistency index table 2.

[0133] Table 2 Average random consistency index table

[0134] Matrix order 1 2 3 4 5 RI 0 0 0.58 0.9 1.12

[0135] Then, the consistency ratio CR of the comparison matrix A is calculated to be 0; since the consistency ratio CR of the comparison matrix A is < 0.1, the comparison matrix A is consistent, and each element in the characteristic vector ω(A) of the comparison matrix A is the relative weight coefficient of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index;

[0136] in,

[0137]

[0138] In the formula, λ max is the maximum eigenvalue of the comparison matrix A.

[0139] The entropy weight matrix method is then used to correct the relative weight coefficients to obtain the comprehensive weight coefficients of reactive compensation margin index C1, response time index C2 and carbon emission intensity index C3, including the following specific steps:

[0140] First, the comparison matrix A is normalized to obtain the normalized matrix B;

[0141] Then calculate the entropy weight matrix D = (d1, d2, d3) according to the following formula:

[0142]

[0143]

[0144] Where, d i is the i-th element in the entropy weight matrix D; x i is the intermediate variable; A ij is the element in the i-th row and j-th column of the comparison matrix A; B ij is the element in the i-th row and j-th column of the normalized matrix B;

[0145] Finally, the comprehensive weight matrix F is calculated according to the following formula. Each element in the comprehensive weight matrix F = [0.0796 0.2492 0.6715] is the comprehensive weight coefficient of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index C3:

[0146]

[0147] In the formula, f i is the i-th element in the comprehensive weight matrix F.

[0148] Finally, according to the comprehensive weight coefficient, the extension matter-element comprehensive evaluation method is adopted to obtain the priority of each output source participating in the system voltage regulation, including the following specific steps:

[0149] Firstly, the classic domain and the node domain are determined, and the priority of each output source participating in the system voltage regulation is divided into two levels: high priority P1 and low priority P2; the dividing points N1, N2 and N3 corresponding to C1, C2 and C3 are 0.5, 100 and 0.3 respectively;

[0150] Among them, the classical domain is:

[0151]

[0152] The section domain is:

[0153]

[0154] In the above formula, R p is a 3D object element; R1 and R2 are R p The first and second sub-element of the substance; P is the priority of each output source participating in the system voltage regulation; P1 is the high priority; P2 is the low priority;

[0155] Then, according to the established classic domain and section domain, the closeness of reactive compensation margin index C1, response time index C2 and carbon emission intensity index C3 of each output source to the high priority P1 and the closeness to the low priority P2 are obtained respectively;

[0156] Then calculate the comprehensive relevance K1 of each output source relative to the high priority and the comprehensive relevance K2 relative to the low priority. For example, for wind power, the closeness m1, m2 and m3 of wind power reactive compensation margin index C1, response time index C2 and carbon emission intensity index C3 relative to the high priority P1 are:

[0157] m1=0.5-C1 m2=C2-100 m3=0.3-C3

[0158] The closeness h1, h2 and h3 of C1, C2 and C3 to the low priority P2 are:

[0159] h1=C1-0.5 h2=100-C2 h3=C3-0.3

[0160] The comprehensive relevance K1 of wind power relative to high priority and the comprehensive relevance K2 of wind power relative to low priority are:

[0161] K1=m1·0.0796+m2·0.2492+m3·0.6715

[0162] K2=h1·0.0796+h2·0.2492+h3·0.6715

[0163] If K1≥K2, the priority of the output source participating in the system voltage regulation is high priority; if K1<K2, the priority of the output source participating in the system voltage regulation is low priority.

Claims

1. A voltage regulation method for a multi-source power system, wherein the output sources of the multi-source power system include at least two of wind power, photovoltaic power, hydropower, and thermal power output sources, characterized in that: The voltage regulation method includes: Real-time acquisition of the attenuation ΔP of the maximum active output of each output source participating in voltage regulation, the increase ΔQ of the maximum reactive output, the time Δt required to complete the reactive increase, and the carbon emission ΔV; When the system voltage deviates from the reference value, the reactive power compensation margin index C1 for evaluating the reactive power compensation margin capability of each output source, the response time index C2 for evaluating the response speed of each output source, and the carbon emission intensity index C3 for evaluating the carbon emission of each output source are calculated; Then, according to the above index, the priority of each output source participating in the system voltage regulation is sorted, and the voltage is regulated according to the priority; The reactive power compensation margin index C1 is the ratio of the attenuation ΔP of the active power output of the output source participating in voltage regulation to the increase ΔQ of the reactive power output. The response time evaluation index C2 is the ratio of the increase in reactive power output ΔQ of the output source participating in voltage regulation to the time Δt required to complete the reactive power increase. The carbon emission intensity index C3 is the ratio of the carbon emission of the output source ΔV to the increase in reactive output ΔQ involved in voltage regulation. The priority of each output source participating in the system voltage regulation is sorted as follows: Firstly, the relative weight coefficients of reactive power compensation margin index C1, response time index C2 and carbon emission intensity index C3 are obtained by using the analytic hierarchy process; Then, the relative weight coefficient is corrected by using the entropy weight matrix method to obtain the comprehensive weight coefficients of the reactive power compensation margin index C1, the response time index C2 and the carbon emission intensity index C3; Finally, according to the comprehensive weight coefficient, the priority of each output source participating in the system voltage regulation is obtained by using the extension matter-element comprehensive evaluation method; The method of using the hierarchical analysis method to obtain the relative weight coefficients of the reactive power compensation margin index C1, the response time index C2 and the carbon emission intensity index C3 includes the following specific steps: Construct a comparison matrix A among the reactive power compensation margin index C1, the response time index C2 and the carbon emission intensity index C3, and set the initial value of each element in the comparison matrix A; According to the initial value, the consistency index CI of the comparison matrix A is calculated, and the average random consistency index RI of the comparison matrix A is obtained, and then the consistency ratio CR of the comparison matrix A is calculated; If the consistency ratio CR of the comparison matrix A is less than 0.1, the comparison matrix A is consistent, and each element in the eigenvector ω(A)=(a1, a2, a3) of the comparison matrix A is the relative weight coefficient of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index; otherwise, the initial value of each element in the comparison matrix A is reset, and the relative weight coefficient of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index is obtained according to the reset initial value according to the above method; in, In the formula, λ max is the maximum eigenvalue of the contrast matrix A; The average random consistency index RI of the comparison matrix A is obtained from the average random consistency index table; Then, the relative weight coefficient is corrected by using the entropy weight matrix method to obtain the comprehensive weight coefficients of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index C3, including the following specific steps: First, the comparison matrix A is normalized to obtain the normalized matrix B; Then calculate the entropy weight matrix D = (d1, d2, d3) according to the following formula: Where, d i is the i-th element in the entropy weight matrix D; x i is the intermediate variable; A ij is the element in the i-th row and j-th column of the comparison matrix A; B ij is the element in the i-th row and j-th column of the normalized matrix B; Finally, the comprehensive weight matrix F is calculated according to the following formula. Each element in the comprehensive weight matrix F = (f1, f2, f3) is the comprehensive weight coefficient of the reactive compensation margin index C1, the response time index C2 and the carbon emission intensity index C3: In the formula, f i is the i-th element in the comprehensive weight matrix F; The step of obtaining the priority of each output source participating in the system voltage regulation by using the extension matter-element comprehensive evaluation method according to the comprehensive weight coefficient includes the following specific steps: Firstly, the classic domain and the node domain are determined, and the priority of each output source participating in the system voltage regulation is divided into two levels: high priority P1 and low priority P2; Among them, the classical domain is: The section domain is: In the above formula, R p is a 3D object element; R1 and R2 are R p The first and second sub-element of the substance; P is the priority of each output source participating in the system voltage regulation; P1 is a high priority; P2 is a low priority; N1, N2 and N3 are the dividing points corresponding to C1, C2 and C3 respectively; Then, according to the established classic domain and node domain, the closeness of reactive compensation margin index C1, response time index C2 and carbon emission intensity index C3 of each output source to the high priority P1 and the closeness to the low priority P2 are obtained respectively; Among them, the closeness m1, m2 and m3 of C1, C2 and C3 to the high priority P1 are: m1=N1-C1 m2=C2-N2 m3=N3-C3 The closeness of C1, C2 and C3 to the low priority P2, h1, h2 and h3, are: h1=C1-N1 h2=N2-C2 h3=C3-N3 Then calculate the comprehensive relevance K1 of each output source relative to the high priority and the comprehensive relevance K2 relative to the low priority according to the following formula, where: The comprehensive relevance K1 relative to the high priority is: K1=m1·f1+m2·f2+m3·f3 The comprehensive relevance K2 relative to the low priority is: K2=h1·f1+h2·f2+h3·f3 Among them, f1, f2, and f3 are the elements in the comprehensive weight matrix F respectively; If K1≥K2, the priority of the output source participating in the system voltage regulation is high priority; if K1<K2, the priority of the output source participating in the system voltage regulation is low priority.

2. The voltage regulation method of a multi-source power system according to claim 1, characterized in that: The attenuation ΔP of the maximum active output of each output source participating in the voltage regulation is the difference between the current active output of each output source and the minimum active output; The increase in the maximum reactive output ΔQ of each output source is the difference between the reactive output under the lowest active output state and the current reactive output; The time Δt and carbon emission intensity ΔV required for each output source to complete reactive power generation are based on actual engineering experience.

Images