Effectiveness analysis method and device for resonance suppression strategy of series branch of power system

Abstract

The invention relates to the technical field of resonance analysis, in particular to an effectiveness analysis method and device for a resonance suppression strategy of a series branch of a power system. According to the method, by constructing the resonance suppression evaluation indexes and constructing the corresponding series branch resonance suppression feasible regions, effectiveness evaluation of series branch resonance suppression is achieved, and the problems that an application scene of an existing resonance suppression method is limited, and a series branch resonance scene is not matched with the resonance suppression method can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of resonance analysis, and in particular to a method and a device for analyzing the effectiveness of a resonance suppression strategy for series branches of an electric power system. Background Art

[0002] Resonance suppression strategies are mostly designed based on specific series / parallel resonance scenarios such as filter resonance, equipment interaction resonance, interaction resonance between equipment and the power grid, and new energy grid-connected resonance. Since the resonance characteristics contain multi-dimensional information such as amplitude, frequency, and phase, the suppression effect of the same resonance suppression strategy in different situations may be very different. Improper strategies may cause the resonance amplification frequency to shift, that is, amplify the resonance peak at the new resonance frequency. However, existing studies pay little attention to the scope and effectiveness of the applicable scenarios of suppression strategies and are mostly aimed at traditional parallel resonances. There is a lack of effectiveness analysis methods for resonance suppression strategies for series branch resonance problems. Therefore, in order to form a better correspondence between resonance suppression strategies and scenarios, it is necessary to study the effectiveness evaluation methods of series branch resonance suppression strategies in different scenarios, which will help promote the application and optimization of series branch resonance suppression methods, and the research on series branch resonance suppression methods is of far-reaching significance. Summary of the invention

[0003] In view of this, the present invention provides a method and device for analyzing the effectiveness of a resonance suppression strategy for series branches of a power system, so as to solve the problem in the prior art of lacking a method for analyzing the effectiveness of a resonance suppression strategy for series branch resonance problems.

[0004] In the first aspect, the present invention provides a method for analyzing the effectiveness of a resonance suppression strategy for a series branch of a power system, the method comprising: determining disturbance injection nodes, resonance branches to be controlled and resonance suppression strategy action nodes based on a branch method; determining a resonance suppression evaluation index based on harmonic current amplitude changes of disturbance injection nodes, resonance branches to be controlled and resonance suppression strategy action nodes before and after resonance suppression, the harmonic current amplitude changes being determined based on a node admittance matrix and a node impedance matrix; determining a series branch resonance suppression feasible domain based on a frequency band of interest, an equivalent impedance and the resonance suppression evaluation index of the resonance suppression strategy; determining an ideal feasible domain of series branch resonance suppression based on an intersection of the series branch resonance suppression feasible domain and a four-quadrant part; and evaluating the effectiveness of the resonance suppression strategy based on a relationship between the equivalent impedance of the resonance suppression strategy and the series branch resonance suppression feasible domain and the ideal feasible domain of series branch resonance suppression.

[0005] In the present invention, the method realizes the effectiveness evaluation of series branch resonance suppression by constructing a resonance suppression evaluation index and a corresponding series branch resonance suppression feasible domain, which can solve the problems that the current resonance suppression method is limited in application scenarios and the series branch resonance scenario is not compatible with the resonance suppression method.

[0006] In the present invention, the ideal feasible domain of series branch resonance suppression is determined based on the intersection of the feasible domain of series branch resonance suppression and the first and fourth quadrants, so that the constructed ideal feasible domain not only takes into account the resonance suppression effect, but also further takes into account that when the equivalent impedance of the resonance suppression strategy is located in the second and third quadrants, negative impedance will be introduced into the system, reducing system damping and causing system instability. Therefore, the ideal feasible domain is used to determine multiple resonance suppression scheme selections and parameter optimization suggestions, which can reduce the risk of system instability.

[0007] In an optional implementation, the method further includes: determining a plurality of resonance suppression scheme selections and parameter optimization suggestions based on an effectiveness evaluation result of the resonance suppression strategy.

[0008] In an optional embodiment, the disturbance injection node, the resonance branch to be controlled and the resonance suppression strategy action node are determined based on the branch method, including: constructing a series branch resonance analysis matrix based on the relationship between the node voltage and the injected current in the power system, the admittance matrix of the series branch in the power system, and the node impedance matrix; performing a frequency scan on the series branch resonance analysis matrix to obtain the series branch resonance distribution, and determining the disturbance injection node, the resonance branch to be controlled and the resonance suppression strategy action node.

[0009] In the present invention, the current is analyzed by the branch method, and a series branch resonance analysis matrix is ​​constructed thereby, which provides a data basis for the series branch resonance analysis; at the same time, it also provides a data basis for evaluating the resonance suppression effect based on the corresponding element value in the series branch resonance analysis matrix, i.e., the series branch harmonic current amplitude.

[0010] In an optional implementation, the resonance suppression evaluation index is expressed by the following formula:

[0011]

[0012] Where D is the admittance matrix of the series branch, C is the correlation matrix, and Z is 0f , Z f They represent the system node impedance matrices before and after resonance suppression at frequency f, m represents the resonance branch to be controlled, p represents the disturbance injection node, and τ is the threshold.

[0013] In the present invention, by adopting the above formula as an evaluation index, a data basis is provided for the accuracy evaluation of the resonance suppression effect.

[0014] In an optional embodiment, the feasible domain of series branch resonance suppression is determined based on the focus frequency band of the resonance suppression strategy, the equivalent impedance and the resonance suppression evaluation index, including: determining the impedance relationship before and after resonance suppression according to the branch addition method and the equivalent impedance of the resonance suppression strategy; substituting the impedance relationship into the resonance suppression evaluation index to obtain the relationship between the equivalent impedance and the impedance after resonance suppression; determining the feasible domain of series branch resonance suppression at a single frequency based on the relationship between the equivalent impedance and the impedance after resonance suppression; determining the feasible domain of series branch resonance suppression within the focus frequency band based on the focus frequency band of the resonance suppression strategy and the feasible domain of series branch resonance suppression at a single frequency.

[0015] In the present invention, after determining the feasible domain of series branch resonance suppression at a single frequency, the feasible domain of series branch resonance suppression within the focus frequency band is further determined according to the focus frequency band of the resonance suppression strategy, so that the constructed feasible domain takes into account the resonance frequency transfer phenomenon, thereby making the effectiveness evaluation of the resonance suppression strategy based on the feasible domain more accurate.

[0016] In an optional embodiment, when τ>0, the boundary of the series branch resonance suppression is a circle with (α, β) as the center and r as the radius, and the inner area of ​​the circle is the feasible domain of the series branch resonance suppression; when τ=0, the boundary of resonance suppression or amplification is a straight line, and the feasible domain of the series branch resonance suppression is one side of the straight line.

[0017] In the present invention, the boundary of the feasible region for suppressing resonance of the series branch is limited, thereby making the determined feasible region more intuitive.

[0018] In an optional embodiment, the effectiveness of the resonance suppression strategy is evaluated based on the relationship between the equivalent impedance of the resonance suppression strategy and the feasible domain of series branch resonance suppression and the ideal feasible domain of series branch resonance suppression, including: comparing the overlap between the equivalent impedances of multiple resonance suppression schemes and the feasible domain of series branch resonance suppression and the ideal feasible domain of series branch resonance suppression in the frequency band of interest, and evaluating the effectiveness of the resonance suppression strategy.

[0019] In a second aspect, the present invention provides an effectiveness analysis device for a resonance suppression strategy of a series branch of a power system, the device comprising: a node determination module, which is used to determine a disturbance injection node, a resonance control branch and an action node of a resonance suppression strategy based on a branch method; an evaluation index determination module, which is used to determine a resonance suppression evaluation index based on the harmonic current amplitude changes of the disturbance injection node, the resonance control branch and the action node of the resonance suppression strategy before and after resonance suppression, and the harmonic current amplitude changes are determined based on a node admittance matrix and a node impedance matrix; a feasible domain determination module, which is used to determine a feasible domain of series branch resonance suppression based on a frequency band of interest, an equivalent impedance and the resonance suppression evaluation index of the resonance suppression strategy; an ideal feasible domain determination module, which determines an ideal feasible domain of series branch resonance suppression based on an intersection of the feasible domain of series branch resonance suppression and a four-quadrant part; an evaluation module, which is used to evaluate the effectiveness of the resonance suppression strategy based on the relationship between the equivalent impedance of the resonance suppression strategy and the feasible domain of series branch resonance suppression and the ideal feasible domain of series branch resonance suppression.

[0020] In a third aspect, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the method for analyzing the effectiveness of the power system series branch resonance suppression strategy of the first aspect or any corresponding embodiment thereof by executing the computer instructions.

[0021] In a fourth aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the effectiveness analysis method of the power system series branch resonance suppression strategy of the first aspect or any corresponding embodiment thereof.

[0022] In a fifth aspect, the present invention provides a computer program product, comprising computer instructions, the computer instructions being used to enable a computer to execute the effectiveness analysis method of the power system series branch resonance suppression strategy of the above-mentioned first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 is a flow chart of a method for analyzing the effectiveness of a power system series branch resonance suppression strategy according to an embodiment of the present invention;

[0025] Figure 2 is a flow chart of another method for analyzing the effectiveness of a power system series branch resonance suppression strategy according to an embodiment of the present invention;

[0026] 3(a) and 3(b) are schematic diagrams showing the distribution of the boundary of the feasible region for suppressing resonance of the series branch when the threshold value τ takes different values ​​according to an embodiment of the present invention;

[0027] Figure 4 is a schematic diagram of a simplified network structure of a power system according to an embodiment of the present invention;

[0028] FIG. 5( a ), FIG. 5( b ) and FIG. 5( c ) are current amplitude-frequency curves of the series branch 1 , the series branch 2 and the series branch 3 according to an embodiment of the present invention;

[0029] 6(a) and 6(b) are schematic diagrams showing the distribution of existing resonance suppression strategies in a feasible domain when the resonance suppression strategy according to an embodiment of the present invention acts on different nodes;

[0030] FIG. 7( a ) and FIG. 7( b ) are series branch current amplitude-frequency curves before and after resonance suppression when the resonance suppression strategy according to an embodiment of the present invention acts on different nodes;

[0031] Figure 8 is a structural block diagram of a device for analyzing the effectiveness of a series branch resonance suppression strategy in a power system according to an embodiment of the present invention;

[0032] Fig. 9 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0034] According to an embodiment of the present invention, an embodiment of a method for analyzing the effectiveness of a series branch resonance suppression strategy in a power system is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0035] In this embodiment, a method for analyzing the effectiveness of a series branch resonance suppression strategy for a power system is provided, which can be used in electronic devices such as computers, mobile phones, tablet computers, etc. Figure 1 is a flow chart of a method for analyzing the effectiveness of a power system series branch resonance suppression strategy according to an embodiment of the present invention. Figure 1 As shown, the process includes the following steps:

[0036] Step S101, determining disturbance injection nodes, resonance control branches and resonance suppression strategy action nodes based on the branch method.

[0037] Specifically, the basic idea of ​​the branch method is to establish the relationship between the series branch current and the node injection current. In a power system, the node injection current refers to the current flowing into the node from the outside, while the series branch current is the current flowing through the series branch (a branch composed of inductors, capacitors, resistors and other components in series). Then, by frequency scanning, changing the frequency of the input signal, and recalculating the relationship between the series branch current and the node injection current, the relationship between the series branch current and the injection current with frequency can be obtained. When the series branch current reaches a peak at a certain frequency, it means that at this frequency, the circuit has a series branch resonance.

[0038] Among them, the series branch determined by the branch method when the series branch resonance occurs is regarded as the resonance branch that needs to be controlled. The resonance suppression strategy injection node is the location where the resonance suppression measures are implemented, that is, by implementing the resonance suppression measures at these locations, the electrical parameters of the node are changed, thereby changing the electrical characteristics of the resonance branch that needs to be controlled, and achieving the purpose of suppressing resonance. In specific implementation, the selection of the resonance suppression strategy action node is usually related to the resonance branch that needs to be controlled. Generally, the suppression strategy is adopted at the node where the resonance branch that needs to be controlled is connected or at the node that can effectively change the electrical parameters of the branch. For example, if a series branch resonates, measures may be taken at the nodes at both ends of the branch connection, such as adding damping resistors at the nodes, installing reactors or capacitors, etc. to change the electrical parameters of the branch.

[0039] The disturbance injection node is usually used to inject disturbance signals and observe the response of the system (such as changes in the current of the series branch, fluctuations in the node voltage, etc.) to detect whether the system is resonant and the characteristics of the resonance. That is, the disturbance injection node is mainly used to diagnose the resonance of the system. Therefore, the disturbance injection node is usually selected at a location that can effectively affect the system state and facilitate monitoring of the system response. In the branch method, the disturbance can be injected into the node close to the series branch or the representative node in the system. For example, in a power system, if there are multiple series branches that may resonate, a disturbance signal, such as a small voltage pulse or current pulse, can be injected into the common bus node connecting these series branches.

[0040] Step S102, based on the change of harmonic current amplitude of the disturbance injection node, the resonance control branch and the resonance suppression strategy action node before and after the resonance suppression, the resonance suppression evaluation index is determined, and the harmonic current amplitude change is determined based on the node admittance matrix and the node impedance matrix. Specifically, according to the analysis of step S101, the series branch resonance is determined by the relationship between the series branch current and the injection current with the frequency, so the resonance suppression evaluation index can be determined by the change of the current amplitude before and after the resonance. The resonance suppression evaluation index can be understood as an evaluation of the resonance suppression effect of the implementation of the resonance suppression strategy. Specifically, when the current amplitude change before and after the resonance meets certain conditions such as meeting a threshold, it is considered that the implemented resonance suppression evaluation strategy has achieved the resonance suppression effect. The change of the harmonic current amplitude is related to the change of the node admittance matrix and the node impedance matrix, so the resonance suppression evaluation index can be further determined by the change of the node admittance matrix and the node impedance matrix.

[0041] Step S103, based on the concerned frequency band of the resonance suppression strategy, the equivalent impedance and the resonance suppression evaluation index, the feasible domain of the series branch resonance suppression is determined. Specifically, when the resonance suppression strategy is implemented at a node in the power system, its equivalent impedance will change, and after different resonance suppression strategies are implemented, the change of equivalent impedance is not the same. Therefore, different resonance suppression strategies can be represented by equivalent impedance in the resonance suppression evaluation index. Then, the corresponding feasible domain is obtained by combining the node impedance change in the evaluation index. The feasible domain can be understood as the area that characterizes the effect of the resonance suppression strategy.

[0042] Since the resonance suppression strategy may cause the resonance frequency shift phenomenon (i.e. the current at the resonance frequency decreases and the current at the surrounding frequency increases), the resonance suppression domain near the resonance frequency range should be analyzed not only at the resonance frequency, but also to determine the corresponding frequency band of interest for each resonance suppression strategy, and further adjust the feasible domain in combination with the frequency band of interest to obtain the feasible domain of resonance suppression of the series branch in the frequency band of interest. The frequency range in the frequency band of interest is [f r -Δf,f r +Δf], where f r is the resonance peak frequency, and the bandwidth Δf can be flexibly designed according to application requirements.

[0043] Step S104, determining the ideal feasible domain of series branch resonance suppression based on the intersection of the feasible domain of series branch resonance suppression and a four-quadrant part; determining the ideal feasible domain of series branch resonance suppression based on the intersection of the feasible domain of series branch resonance suppression and a four-quadrant part, so that the constructed ideal feasible domain not only takes into account the resonance suppression effect, but also further takes into account that when the equivalent impedance of the resonance suppression strategy is located in the second and third quadrants, negative impedance will be introduced into the system, reducing system damping and causing system instability. Therefore, the ideal feasible domain is used to determine multiple resonance suppression scheme selections and parameter optimization suggestions, which can reduce the risk of system instability.

[0044] Step S105, based on the relationship between the equivalent impedance of the resonance suppression strategy and the feasible domain of series branch resonance suppression and the ideal feasible domain of series branch resonance suppression, the effectiveness of the resonance suppression strategy is evaluated. Specifically, the effectiveness of the corresponding resonance suppression scheme can be evaluated by the distribution of the equivalent impedance of the resonance suppression scheme in the feasible domain.

[0045] The embodiment of the present invention provides a method for analyzing the effectiveness of a series branch resonance suppression strategy for a power system. The method constructs a resonance suppression evaluation index and a corresponding series branch resonance suppression feasible domain, thereby realizing an effectiveness evaluation of series branch resonance suppression. The method can solve the problems of limited application scenarios of current resonance suppression methods and incompatibility between series branch resonance scenarios and resonance suppression methods.

[0046] In this embodiment, a method for analyzing the effectiveness of a power system series branch resonance suppression strategy is provided. Figure 2 As shown, the method comprises the following steps:

[0047] Step S201, determining the disturbance injection node, the resonance control branch and the resonance suppression strategy action node based on the branch method.

[0048] Specifically, the above step S201 includes:

[0049] Step S2011, constructing a series branch resonance analysis matrix based on the relationship between node voltage and injection current in the power system, the admittance matrix of the series branch in the power system, and the node impedance matrix.

[0050] Step S2012, frequency scanning the series branch resonance analysis matrix to obtain the series branch resonance distribution, determine the disturbance injection node, the resonance control branch and the resonance suppression strategy action node.

[0051] For an n-node system, the relationship between the node voltage and the injected current is as follows:

[0052]

[0053] U=Y -1I (2)

[0054] Where Y is the node admittance matrix, U is the node voltage vector, and I is the injected node current vector.

[0055] The voltage of branch m between nodes i and j is:

[0056] U' m =U i -U j (3)

[0057] The connection relationship and coupling degree between nodes can be obtained from the elements of matrix Y. Assuming there are r independent series branches, the branches are numbered in the order from the initial node from small to large, and we have:

[0058]

[0059] U'=CU (5)

[0060] Where C is the incidence matrix. Assume that branch m is between node i and node j, and y ij ≠0, then:

[0061]

[0062] From equations (3) and (6), we can get the current of series branch m as J m =-U′ m y ij , d m =-y ij .

[0063] The admittance matrix of the series branch is:

[0064] D=diag(d1,d2,K,d r ) (7)

[0065] At this time, the branch current vector J=[J1,J2,K,J r ] T for:

[0066] J=DCU (8)

[0067] Combining formula (2) with formula (8), we can get:

[0068] J=HI (9)

[0069] H=DCY -1 =DCZ (10)

[0070] Where: Z is the node impedance matrix.

[0071] When unit harmonic current is injected into node i, the current of each series branch in the power grid is shown in formula (11):

[0072]

[0073] At this time, the change of each element in the matrix H with frequency can represent the change law of the harmonic current amplification of any series branch with frequency. When the harmonic current amplification frequency is the same as the system series branch resonance frequency (that is, when each element in H has a maximum value point), the system series branch resonance is the reason for the amplification peak of the series branch harmonic current. Therefore, the relationship between the series branch current and the injected current with frequency can reflect the system series branch resonance. The matrix H is the series branch resonance analysis matrix. By analyzing the frequency sweep results of each element in the matrix H, the system series branch resonance distribution is obtained, and the resonance branch to be governed and the action node of the suppression method are determined. At the same time, the resonance suppression effect can be evaluated by the effect of suppressing the amplitude of the series branch harmonic current (that is, the amplitude of the corresponding element in the series branch resonance analysis matrix H).

[0074] Step S202, determining a resonance suppression evaluation index based on the harmonic current amplitude changes of the disturbance injection node, the resonance control branch and the resonance suppression strategy action node before and after resonance suppression, wherein the harmonic current amplitude changes are determined based on the node admittance matrix and the node impedance matrix.

[0075] Specifically, if the disturbance injection node is p, the resonance branch to be controlled is m, and the resonance suppression strategy acts on node s. The resonance suppression effect of the series branch resonance suppression strategy can be reflected by the change in the amplitude of the corresponding elements in the series branch resonance analysis matrix H before and after suppression. The corresponding elements in the matrix H before and after resonance suppression at frequency f are H 0f (m,p),H f (m,p). When the change of the corresponding element is greater than the threshold, it can be considered that the resonance of branch m in series is suppressed, that is:

[0076] |H 0,f (m,p)| 2 -|H f (m,p)| 2 >τ (12)

[0077] Where τ is the threshold, τ ≥ 0. The value of τ can be flexibly selected according to the needs of the actual project.

[0078] From equations (5), (7) and (10), it can be seen that the resonance suppression strategy only affects the node admittance matrix, so equation (12) can be transformed into:

[0079]

[0080] In the formula, Z 0f , Zf They respectively represent the system node impedance matrix before and after resonance suppression at frequency f.

[0081] Further sorting:

[0082] |Z 0,f (i,p)-Z 0,f (j,p)| 2 -|Z f (i,p)-Z f (j,p)| 2 >τ|z l,m | 2 (14)

[0083] Where: i and j are the nodes at both ends of branch m, z l,m is the impedance of branch m, || represents the amplitude.

[0084] Step S203, determining a feasible region for series branch resonance suppression based on the concerned frequency band, equivalent impedance and the resonance suppression evaluation index of the resonance suppression strategy;

[0085] Specifically, the above step S203 includes:

[0086] Step S2031, determining the impedance relationship before and after resonance suppression according to the branch adding method and the equivalent impedance of the resonance suppression strategy.

[0087] Step S2032: Substitute the impedance relationship into the resonance suppression evaluation index to obtain the relationship between the equivalent impedance and the impedance after resonance suppression.

[0088] Step S2033, determining a feasible region for series branch resonance suppression at a single frequency based on the relationship between the equivalent impedance and the impedance after resonance suppression.

[0089] Step S2034, determining a feasible region for series branch resonance suppression within the frequency band of interest based on the frequency band of interest of the resonance suppression strategy and a feasible region for series branch resonance suppression at a single frequency.

[0090] Among them, the branch addition method is a method of gradually building a circuit model and solving the node impedance matrix. In circuit analysis, you may start with a simple basic circuit, and then gradually add branches (such as branches composed of resistors, inductors, capacitors and other components) to build a complete circuit model. Each additional branch will have a corresponding impact on the node impedance matrix, and the node impedance matrix is ​​updated through a series of matrix operations. Therefore, the resonance suppression strategy implemented in the power system is equivalent to adding a ground-connected branch with an impedance of δ to the system (that is, a branch with one end connected to the system node and the other end grounded). Therefore, Z in formula (14) f (i,p),Z f (j,p) can be transformed into:

[0091]

[0092] In the formula, δ represents the equivalent impedance corresponding to the resonance suppression strategy. To simplify the symbols, the subscript f will be omitted in the following text.

[0093] Substituting equations (15) and (16) into equation (14) and further rearranging, we can obtain:

[0094]

[0095] Where: A=(z is -z js ) sp , B = z ip -z jp , C=AB * .z is is the mutual impedance between system node i and node s before resonance suppression, z js 、z sp 、z ip 、z jp Similarly. ss,r 、z ss,i is the real and imaginary part of the self-impedance of the system node s before resonance suppression. The impedance of each node in the system can be obtained by inverting the system node admittance matrix before suppression. * is the conjugate of B, δ r , δ i denote the real and imaginary parts of δ, respectively, C r , C i Represent the real part and imaginary part of C respectively. Whether the threshold in formula (17) is 0 will affect the final expression of the criterion. Further deduction shows that the series branch resonance suppression feasible domain (SRSD) is:

[0096] Ω SRS ={(δ r ,δ i )ε1(δ r ,δ i )<0} (18)

[0097]

[0098] α=[(|B| 2 -τ|z l,m | 2 ) ss,r -C r ] / (τ|z l,m | 2 ) (20)

[0099] β=[(|B| 2 -τ|zl,m | 2 ) ss,i -C i ] / (τ|z l,m | 2 ) (twenty one)

[0100]

[0101] It can be seen from equations (18)-(22) that when τ>0, the boundary of the series branch resonance suppression is a circle with (α, β) as the center and r as the radius, and the inner area of ​​the circle is the feasible domain of series branch resonance suppression; when τ=0, the boundary of resonance suppression / amplification is a straight line, and the feasible domain of series branch resonance suppression is one side of the straight line.

[0102] It can be seen from formula (19) that the feasible domain of series branch resonance suppression decouples the equivalent impedance of the resonance suppression strategy from the series branch resonance analysis matrix H. By observing the distribution position of the equivalent impedance of the resonance suppression strategy in the feasible domain, it can be used to judge the rationality of the resonance suppression strategy and optimize it. The distribution of the feasible domain of series branch resonance suppression when τ is 0 can be used to judge the effect of the suppression strategy on resonance (i.e., whether the resonance is reduced or amplified); the feasible domain of resonance suppression when τ>0 can be used to judge the suppression effect of the suppression strategy on resonance (i.e., resonance is reduced), and guide the design of the resonance suppression strategy.

[0103] The feasible domain of series branch resonance suppression determined by the above method is the feasible domain of series branch resonance suppression at a single frequency. However, given that resonance is usually presented in the form of a resonance peak, the frequency band around the resonance frequency will also have a large current distribution, that is, resonance suppression should pay attention to the frequency band around the resonance frequency in addition to paying attention to the feasible domain distribution at the resonance frequency. Therefore, the range and frequency interval of the resonance frequency band of interest should be given, and the feasible domain of series branch resonance suppression within the frequency band should be drawn one by one. The frequency band of interest should be designed according to the analysis and suppression requirements under different scenarios and resonance characteristics.

[0104] The distribution of the feasible domain boundary of the resonance suppression of the series branch at the resonant frequency and at different frequency points in the frequency band is shown in Figure 3(a) and Figure 3(b), where Figure 3(a) shows the schematic diagram of the distribution of the feasible domain boundary of the resonance suppression of the series branch when τ = 0, and Figure 3(b) shows the schematic diagram of the distribution of the feasible domain boundary of the resonance suppression of the series branch when τ = 0.5. When the threshold is selected as 0, the boundary of the feasible domain of the resonance suppression of the series branch at a certain frequency is a straight line, and the two sides of the straight line are the resonance amplification area and the suppression area, respectively. The dotted line corresponds to the boundary of the resonance suppression feasible domain at the resonance peak frequency, and the solid line corresponds to the boundary of the resonance suppression feasible domain at other frequencies in the frequency band of interest; when the threshold is not selected as 0, the area inside the circle of any circular boundary in the figure is the resonance suppression feasible domain of its equivalent impedance.

[0105] In order to ensure that the resonance suppression effect is achieved within a certain resonance frequency band, the equivalent impedance of the resonance suppression strategy needs to be within the feasible domain of resonance suppression at each frequency at the same time.

[0106] Step S204, based on the intersection of the feasible domain of series branch resonance suppression and the one-four-quadrant part, the ideal feasible domain of series branch resonance suppression is determined; specifically, when the equivalent impedance of the resonance suppression strategy is located in the second three quadrants, negative impedance will be introduced into the system, reducing the system damping and causing instability in the system. Therefore, based on the intersection of the feasible domain of series branch resonance suppression and the one-four-quadrant part, the ideal feasible domain of series branch resonance suppression is determined, corresponding to the gray shaded area in the figure. The admittance change is always in the ideal feasible domain within the frequency band, which is a sufficient condition for the resonance to be safely and effectively suppressed.

[0107] Step S205, based on the relationship between the equivalent impedance of the resonance suppression strategy and the feasible domain of series branch resonance suppression and the ideal feasible domain of series branch resonance suppression, the effectiveness of the resonance suppression strategy is evaluated. Specifically, the existing resonance suppression strategies mainly include active damping control, installation of resonance suppression equipment, change of system parameters, etc. The impact of the access of the resonance suppression strategy on the system operation state can be reflected by its equivalent impedance. By comparing the overlap of the distribution of equivalent impedances under different resonance suppression strategies and parameters with the feasible domain of series branch resonance suppression in the frequency band, the effectiveness of the resonance suppression strategy can be judged. Among them, when judging, if the equivalent impedance of the resonance suppression strategy is simultaneously located in the feasible domain of resonance suppression of each frequency, it means that the resonance suppression effect is played in the frequency band of interest of resonance suppression.

[0108] Step S206, based on the effectiveness evaluation result of the resonance suppression strategy, multiple resonance suppression scheme selections and parameter optimization suggestions are determined. Specifically, after determining the ideal feasible domain of series branch resonance suppression, the resonance suppression strategy selection and parameter optimization suggestions can be given by comprehensively considering the resonance suppression strategy effectiveness analysis conclusion in step S205 and combining the overlap between the resonance suppression strategy and the ideal feasible domain.

[0109] As a specific application example of the present invention, in order to verify the effectiveness analysis method of the proposed power system series branch resonance suppression strategy, Figure 4 The model is the analysis object. The model includes three series branches. Each branch includes a voltage source converter (VSC) composed of an LCL filter (including two inductors and one capacitor) and a switching element. The impedance between the VSC and the grid connection point is represented by Z l Indicates that the grid connection point to the grid u g The impedance between Z gIndicates that nodes 2, 3, and 4 respectively represent the output terminal positions of the VSC, and node 1 represents the bus position to which the three branches are connected. In this embodiment, nodes 1, 2, 3, and 4 are used as disturbance injection nodes, I1, I2, I3, and I4 respectively represent the current vectors of the corresponding injection nodes, and J1, J2, and J3 respectively represent the current vectors of the three branches. Figure 4 The parameter settings of the model are shown in Table 1 below.

[0110] Table 1

[0111]

[0112]

[0113] Establish Figure 4 The node admittance matrix of the mathematical model is Y, the admittance matrix of the series branch is D and the correlation matrix is ​​C, and the series branch resonance analysis matrix H is established according to formula (10). The specific modeling process is omitted here. By analyzing the frequency sweep results of each element in the matrix H, the resonance distribution of the system series branch is obtained as shown in Figure 5(a), Figure 5(b) and Figure 5(c). Among them, Figure 5(a) shows the current amplitude-frequency curve of series branch 1, Figure 5(b) shows the current amplitude-frequency curve of series branch 2, and Figure 5(c) shows the current amplitude-frequency curve of series branch 3. Branch 1 and branch 2 are branches with the same parameters, and both have two resonance points of 625Hz and 742Hz. When the disturbance injection node is a node at both ends of the branch, the 625Hz resonance point will have a slight frequency offset. Among the two resonance points of branch 1, the 742Hz harmonic current amplification is the most serious when the disturbance injection nodes are 2 and 3, and branch 2 is similar. There is only one obvious resonance point of 742 Hz in branch 3, and the harmonic current amplification is more serious only when the disturbance injection node is 4.

[0114] The effectiveness of the resonance suppression strategy can be evaluated by using the feasible domain of the resonance suppression of the series branch when τ is 0 proposed in this embodiment. Taking the two resonance suppression strategies of virtual impedance and passive damping of resistor and capacitor in series, resistor and inductor in series as examples, for the 742Hz series branch resonance of branch 1 when the disturbance injection node is 2 in this example, the corresponding frequency band of interest is 722Hz-762Hz. Figure 6(a) shows the distribution of the feasible domain of resonance suppression of the series branch when the resonance suppression strategy acts on node 2, and Figure 6(b) shows the distribution of the feasible domain of resonance suppression of the series branch when the resonance suppression strategy acts on node 3. At the same time, Figures 6(a) and 6(b) also show the impedance changes of 1Ω-5Ω virtual impedance, passive damping of resistor 0.01Ω-0.05Ω and capacitor 5μF-25μF in series, and passive damping of resistor 0.01Ω-0.05Ω and inductor 1mH-5mH in series, and compare the impedance distribution in the three cases with the boundary.

[0115] From the feasible domain expressions of series branch resonance suppression in equations (18)-(22), it can be seen that the distribution of the feasible domain of series branch resonance suppression is related to the self-impedance of the node where the resonance suppression strategy works and the mutual impedance between the node where the resonance suppression strategy works and the nodes at both ends of the branch. The coefficients A and z in the corresponding expressions are ss , when the resonance suppression strategy acts on different nodes, the coefficients A and z ss The difference makes the distribution of the feasible domain of series branch resonance suppression different. Figure 6(a) and 6(b) This phenomenon can be seen. When the resonance suppression strategy acts on node 2 (as shown in Figure 6 (a)), the ideal feasible domain range of the resonance suppression of the series branch is the largest, and the virtual impedance is always within the ideal feasible domain; when the passive damping corresponds to a small access impedance, it is within the ideal feasible domain, but as the impedance value (corresponding to a decrease in capacitance and an increase in inductance) increases, the passive damping gradually enters the resonance amplification region of certain frequency bands, which leads to resonance amplification of some frequencies in the frequency band. When the parameters are further increased, it may even lead to resonance peak amplification. When the resonance suppression strategy acts on node 3 (as shown in Figure 6 (b)), the ideal feasible domain range of the resonance suppression of the series branch is smaller than when it acts on node 2. Neither the virtual impedance nor the passive damping is within the ideal feasible domain, that is, it is located in the resonance amplification region of certain frequencies, resulting in resonance amplification of some frequency bands.

[0116] From the above analysis, it can be seen that the virtual impedance resonance suppression strategy has a good suppression effect on the 742 Hz series branch resonance of series branch 1 when acting on node 2.

[0117] Taking passive damping scheme 1 with 4Ω virtual impedance, 0.03Ω resistor and 15μF capacitor in series and passive damping scheme 2 with 0.05Ω resistor and 5mH inductor in series as examples, a frequency sweep analysis of series branch resonance is performed to verify the accuracy of the effectiveness evaluation method of the resonance suppression strategy based on the feasible domain of series branch resonance suppression. Figure 7(a) shows the series branch current amplitude-frequency curve before and after resonance suppression when the resonance suppression strategy acts on node 2; Figure 7(b) shows the series branch current amplitude-frequency curve before and after resonance suppression when the resonance suppression strategy acts on node 2. Figure 7(a) and 7(b) It can be seen that when the virtual impedance acts on nodes 2 and 3, most of the harmonic currents in the frequency range are reduced, which suppresses the resonance. However, the access of passive damping causes the resonant frequency to shift and the harmonic currents in the frequency band of interest to be amplified. Figure 6(a) and 6(b) The analysis results are consistent.

[0118] The effectiveness of the above resonance suppression methods is evaluated in Figure 6(a) and 6(b)As well as in Figure 7(a) and Figure 7(b), the drawing of the series branch current amplitude-frequency curve in Figure 7(a) and Figure 7(b) requires substituting the mathematical model of the resonance suppression method into the admittance matrix Y in the series branch resonance analysis matrix H one by one and inverting it, which requires a large amount of calculation. Figure 6(a) and 6(b) The feasible domain analysis only starts from the perspective of equivalent impedance of the resonance suppression strategy. By analyzing the distribution of equivalent impedance in the feasible domain, the rationality of the resonance suppression method can be directly judged and parameter setting suggestions can be given. The analysis results are more efficient and direct.

[0119] Through the above description, the basic functions of the effectiveness analysis method of the power system series branch resonance suppression strategy have been explained. The feasible domain analysis method of the power system series branch resonance suppression provided by the present invention can evaluate the effectiveness of the series branch resonance suppression strategy in different scenarios and provide design guidance, avoiding the inverse calculation of the complex matrix for each suppression scenario, simplifying the evaluation process, and having good applicability to different types of resonance suppression strategies. It is of great significance to solve the problem that the current resonance suppression method is limited in application scenarios and the series branch resonance scenario is not compatible with the resonance suppression method.

[0120] In this embodiment, a device for analyzing the effectiveness of a power system series branch resonance suppression strategy is also provided, and the device is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. As used below, the term "module" can implement a combination of software and / or hardware of a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0121] This embodiment provides a device for analyzing the effectiveness of a series branch resonance suppression strategy in a power system. Figure 8 As shown, including:

[0122] A node determination module 81 is used to determine the disturbance injection node, the resonance control branch and the resonance suppression strategy action node based on the branch method;

[0123] An evaluation index determination module 82 is used to determine a resonance suppression evaluation index based on the harmonic current amplitude changes of the disturbance injection node, the resonance control branch and the resonance suppression strategy action node before and after the resonance suppression, and the harmonic current amplitude changes are determined based on the node admittance matrix and the node impedance matrix;

[0124] A feasible domain determination module 83, used to determine the feasible domain of series branch resonance suppression based on the concerned frequency band of the resonance suppression strategy, the equivalent impedance and the resonance suppression evaluation index;

[0125] An ideal feasible region determination module 84 determines an ideal feasible region for series branch resonance suppression based on an intersection of a series branch resonance suppression feasible region and a four-quadrant part;

[0126] The evaluation module 85 is used to evaluate the effectiveness of the resonance suppression strategy based on the relationship between the equivalent impedance of the resonance suppression strategy and the feasible domain of the series branch resonance suppression and the ideal feasible domain of the series branch resonance suppression.

[0127] In an optional implementation, the device further includes: an optimization module, configured to determine a plurality of resonance suppression scheme selections and parameter optimization suggestions based on the effectiveness evaluation results of the resonance suppression strategy.

[0128] In an optional embodiment, the node determination module is specifically used to construct a series branch resonance analysis matrix based on the relationship between the node voltage and the injected current in the power system, the admittance matrix of the series branch in the power system, and the node impedance matrix; perform a frequency scan on the series branch resonance analysis matrix to obtain the series branch resonance distribution, and determine the disturbance injection node, the resonance branch to be controlled, and the node where the resonance suppression strategy acts.

[0129] In an optional implementation, the resonance suppression evaluation index is expressed by the following formula:

[0130]

[0131] Where D is the admittance matrix of the series branch, C is the correlation matrix, and Z is 0f , Z f They represent the system node impedance matrices before and after resonance suppression at frequency f, m represents the resonance branch to be controlled, p represents the disturbance injection node, and τ is the threshold.

[0132] In an optional embodiment, the feasible domain determination module is specifically used to: determine the impedance relationship before and after resonance suppression based on the equivalent impedance of the branch addition method and the resonance suppression strategy; substitute the impedance relationship into the resonance suppression evaluation index to obtain the relationship between the equivalent impedance and the impedance after resonance suppression; determine the feasible domain of series branch resonance suppression at a single frequency based on the relationship between the equivalent impedance and the impedance after resonance suppression; determine the feasible domain of series branch resonance suppression within the frequency band of interest based on the frequency band of interest of the resonance suppression strategy and the feasible domain of series branch resonance suppression at a single frequency.

[0133] In an optional embodiment, when τ>0, the boundary of the series branch resonance suppression is a circle with (α, β) as the center and r as the radius, and the inner area of ​​the circle is the feasible domain of the series branch resonance suppression; when τ=0, the boundary of resonance suppression or amplification is a straight line, and the feasible domain of the series branch resonance suppression is one side of the straight line.

[0134] In an optional implementation, the evaluation module is specifically used to compare the equivalent impedances of multiple resonance suppression schemes with the overlap between the feasible domain of series branch resonance suppression and the ideal feasible domain of series branch resonance suppression in the frequency band of interest, so as to evaluate the effectiveness of the resonance suppression strategy.

[0135] The further functional description of each of the above modules is the same as that of the above corresponding embodiments and will not be repeated here.

[0136] The embodiment of the present invention also provides a computer device having the above Figure 8 The effectiveness analysis device of the power system series branch resonance suppression strategy is shown.

[0137] See also Fig. 9 , Fig. 9 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Fig. 9 As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process the instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as, a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Fig. 9 A processor 10 is taken as an example.

[0138] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0139] The memory 20 stores instructions executable by at least one processor 10, so that at least one processor 10 executes the method shown in the above embodiment.

[0140] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created by the use of a computer device based on the presentation of a small program landing page, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0141] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0142] The computer device further comprises a communication interface 30 for the computer device to communicate with other devices or a communication network.

[0143] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0144] A part of the present invention may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should understand that the existence of the computer program instruction in a computer-readable medium includes, but is not limited to, a source file, an executable file, an installation package file, etc., and accordingly, the way in which the computer program instruction is executed by the computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium may be any available computer-readable storage medium or communication medium accessible to the computer.

[0145] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A method for analyzing the effectiveness of a series branch resonance suppression strategy for a power system, characterized in that: The method comprises: Based on the branch method, the disturbance injection node, the resonance branch to be controlled and the resonance suppression strategy action node are determined; The resonance suppression evaluation index is determined based on the harmonic current amplitude changes of the disturbance injection nodes, the resonance control branches and the resonance suppression strategy action nodes before and after the resonance suppression. The harmonic current amplitude changes are determined based on the node admittance matrix and the node impedance matrix. Determine the feasible domain of series branch resonance suppression based on the concerned frequency band, equivalent impedance and the resonance suppression evaluation index of the resonance suppression strategy; Based on the intersection of the feasible region for series branch resonance suppression and a four-quadrant part, the ideal feasible region for series branch resonance suppression is determined; Based on the relationship between the equivalent impedance of the resonance suppression strategy and the feasible region of series branch resonance suppression and the ideal feasible region of series branch resonance suppression, the effectiveness of the resonance suppression strategy is evaluated.

2. The method according to claim 1, characterized in that The method further comprises: Based on the effectiveness evaluation results of the resonance suppression strategy, multiple resonance suppression scheme selections and parameter optimization recommendations are determined.

3. The method according to claim 1, characterized in that Based on the branch method, the disturbance injection node, the resonance branch to be controlled and the resonance suppression strategy action node are determined, including: Construct a series branch resonance analysis matrix based on the relationship between node voltage and injected current in the power system, the admittance matrix of the series branch in the power system, and the node impedance matrix; The resonance analysis matrix of the series branch is frequency scanned to obtain the resonance distribution of the series branch, and the disturbance injection node, the resonance branch to be controlled, and the node where the resonance suppression strategy works are determined.

4. The method according to claim 3, characterized in that The resonance suppression evaluation index is expressed by the following formula: Where D is the admittance matrix of the series branch, C is the correlation matrix, and Z is 0f , Z f They represent the system node impedance matrices before and after resonance suppression at frequency f, m represents the resonance branch to be controlled, p represents the disturbance injection node, and τ is the threshold.

5. The method according to claim 1, characterized in that The feasible domain of series branch resonance suppression is determined based on the concerned frequency band, equivalent impedance and the resonance suppression evaluation index of the resonance suppression strategy, including: Determine the impedance relationship before and after resonance suppression based on the branch addition method and the equivalent impedance of the resonance suppression strategy; Substituting the impedance relationship into the resonance suppression evaluation index to obtain the relationship between the equivalent impedance and the impedance after resonance suppression; Determine a feasible domain for series branch resonance suppression at a single frequency based on the relationship between the equivalent impedance and the impedance after resonance suppression; The feasible domain of series branch resonance suppression within the frequency band of interest is determined based on the frequency band of interest of the resonance suppression strategy and the feasible domain of series branch resonance suppression at a single frequency.

6. The method according to claim 5, characterized in that: When τ>0, the boundary of series branch resonance suppression is a circle with (α, β) as the center and r as the radius, and the inner area of ​​the circle is the feasible domain of series branch resonance suppression; when τ=0, the boundary of resonance suppression or amplification is a straight line, and the feasible domain of series branch resonance suppression is one side of the straight line.

7. The method according to claim 5, characterized in that Based on the relationship between the equivalent impedance of the resonance suppression strategy and the feasible region of the series branch resonance suppression and the ideal feasible region of the series branch resonance suppression, the effectiveness of the resonance suppression strategy is evaluated, including: The effectiveness of the resonance suppression strategy is evaluated by comparing the equivalent impedances of multiple resonance suppression schemes with the overlap of the feasible domain of series branch resonance suppression and the ideal feasible domain of series branch resonance suppression within the frequency band of interest.

8. A device for analyzing the effectiveness of a series branch resonance suppression strategy in a power system, characterized in that: The device comprises: A node determination module is used to determine the disturbance injection node, the resonance control branch and the resonance suppression strategy action node based on the branch method; An evaluation index determination module is used to determine the resonance suppression evaluation index based on the harmonic current amplitude changes of the disturbance injection node, the resonance control branch and the resonance suppression strategy action node before and after the resonance suppression, and the harmonic current amplitude changes are determined based on the node admittance matrix and the node impedance matrix; A feasible domain determination module, used to determine a feasible domain for series branch resonance suppression based on a concerned frequency band, equivalent impedance and the resonance suppression evaluation index of the resonance suppression strategy; An ideal feasible region determination module determines an ideal feasible region for series branch resonance suppression based on the intersection of the series branch resonance suppression feasible region and a four-quadrant part; The evaluation module is used to evaluate the effectiveness of the resonance suppression strategy based on the relationship between the equivalent impedance of the resonance suppression strategy and the feasible domain of the series branch resonance suppression and the ideal feasible domain of the series branch resonance suppression.

9. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the effectiveness analysis method of the power system series branch resonance suppression strategy according to any one of claims 1 to 7 by executing the computer instructions.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the effectiveness analysis method of the power system series branch resonance suppression strategy according to any one of claims 1 to 7.

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