A real-time adjustable capacity calculation method for power quality regulation resource combination

Abstract

The application provides a real-time adjustable capacity calculation method for power quality regulation resource combination, and belongs to the field of power regulation, and comprises the following steps: step 1: acquiring and solving m single regulation resources required for real-time power parameter calculation, based on a power decomposition method, each type of compensation capacity of each single regulation resource real-time output is calculated by decomposition; step 2: calculating the real-time compensated output capacity of each single regulation resource and the real-time adjustable capacity of each single regulation resource; step 3: based on the calculation formula of the real-time adjustable capacity of each single regulation resource, the real-time adjustable capacity of the power quality regulation resource combination is integrated. The application helps to realize the combined optimization configuration of a large number of heterogeneous power quality regulation resources in a power grid.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of electric energy regulation, and particularly relates to a real-time adjustable capacity calculation method for power quality regulation resource combination. BACKGROUND

[0002] With the deepening of the construction of new power systems, a large number of grid-related converters are widely connected, the scale of disturbance sources and governance resources is rapidly expanded, power quality problems are scattered in multiple points, and are coupled in multiple frequency bands and dynamically related in wide time and space. The power supply and utilization system has evolved into a complex system. At the same time, the governance demand of multiple time scales and the regulation capacity of a large number of heterogeneous resources are dynamically time-varying. The efficient governance of complex giant systems with multiple targets, multiple frequency bands, and multiple time scales of global power quality faces severe challenges.

[0003] At present, the demand for optimal configuration of power quality regulation resource combination of power grid is increasing, but there is still a lack of real-time adjustable capacity calculation method for power quality regulation resource combination, and the traditional real-time adjustable capacity calculation method of single regulation resource has the disadvantages of insufficient precision and poor applicability. SUMMARY

[0004] In order to accurately and effectively calculate the real-time adjustable capacity of power quality regulation resource combination, and to help realize the optimal configuration of a large number of heterogeneous power quality regulation resources, the present application provides a real-time adjustable capacity calculation method for power quality regulation resource combination. The power decomposition method is applied to first decompose and calculate the equivalent capacity and real-time adjustable capacity of each type of compensation output by each single regulation resource, and then obtain the real-time adjustable capacity of the power quality regulation resource combination, thereby providing a general calculation method for the real-time adjustable capacity of any type of power quality regulation resource combination, to help realize the optimal configuration of a large number of heterogeneous power quality regulation resources in the power grid.

[0005] To achieve the above purpose, the present application adopts the following technical solution:

[0006] A real-time adjustable capacity calculation method for power quality regulation resource combination, comprising the following steps:

[0007] Step 1: Obtain and solve the real-time power parameters required for m single regulation resource calculation, based on the power decomposition method, decompose and calculate the real-time fundamental positive sequence capacity, real-time unbalanced compensation equivalent capacity, and real-time harmonic compensation equivalent capacity output by each single regulation resource in real time;

[0008] Step 2: Calculate the real-time compensated output capacity of each single regulation resource and the real-time adjustable capacity of each single regulation resource;

[0009] Step 3: Based on the calculation formula of the real-time adjustable capacity of each single regulation resource, the real-time adjustable capacity of the power quality regulation resource combination is integrated.

[0010] Advantages:

[0011] 1、The power decomposition method is used as a basis to independently and in detail solve equivalent capacities of different compensation types, and the method has better accuracy compared with traditional general methods.

[0012] 2、The method can be directly applied to the case that power quality regulation resources simultaneously output any combination of compensation types, and is not limited to specific power quality regulation resources, has wide applicability, and can be well applied to the combined optimization configuration of a large number of heterogeneous power quality regulation resources. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 A power grid simplified connection schematic diagram of a power quality regulation resource combination is provided for the application.

[0014] Figure 2 A flowchart of a real-time adjustable capacity calculation method of a power quality regulation resource combination is provided for the application.

[0015] Figure 3 A simulation calculation result comparison chart. DETAILED DESCRIPTION

[0016] In order to make the objectives, technical solutions and advantages of the application clearer, the application is further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the application, and are not used to limit the application. In addition, the technical features involved in each embodiment of the application described below can be combined with each other as long as they do not conflict with each other.

[0017] As shown in Figure 2 The application provides a real-time adjustable capacity calculation method of a power quality regulation resource combination, comprising the following steps:

[0018] Step 1: Obtain and solve real-time power parameters required for m single regulation resource calculation, based on a power decomposition method, decompose and calculate each type of compensation capacity output by each single regulation resource in real time, including:

[0019] Step 11: Obtain and solve various real-time power parameters:

[0020] Measure and obtain real-time working voltage and current data of each single regulation resource in the power quality regulation resource combination, and obtain effective values of each harmonic voltage and current and positive, negative and zero sequence component effective values of fundamental voltage and current based on an FFT (fast Fourier transform) decomposition method and a symmetrical component method.

[0021] Taking a power quality regulation resource combination containing SVG (static var generator), STATCOM (static synchronous compensator), APF (active power filter) and UPQC (unified power quality controller) as an example for analysis. Figure 1 A simplified connection diagram of a power grid of a power quality regulation resource combination containing m single regulation resources shown in the present application is shown in the figure, assuming that the regional power grid is a three-phase three-wire system, and the m single regulation resources are connected to the power grid in parallel, wherein i is the single regulation resource number, u i , i i are the total voltage and current instantaneous values output by the i th single regulation resource, respectively, and the real-time power parameters required by the present application can be obtained by measuring and calculating them. PCC is the common connection point of each single regulation resource and the power grid.

[0022] Based on the power decomposition method, in a three-phase three-wire system, the calculation method of each type of single regulation resource has uniformity, so the i th single regulation resource is taken as an example for analysis and calculation, and the following power parameters are calculated according to the voltage and current measurement data:

[0023] (1)

[0024] Wherein, i is the single regulation resource number, j is the harmonic number, and n is the maximum harmonic number, are the j th harmonic current effective value, j th harmonic voltage effective value, total non-fundamental current effective value, and total non-fundamental voltage effective value output by the i th single regulation resource in real time; are the positive and negative sequence component effective values of the fundamental current and the positive and negative sequence component effective values of the fundamental voltage output by the i th single regulation resource in real time, are the unbalanced voltage effective value and unbalanced current effective value output by the i th single regulation resource in real time.

[0025] Step 12: Calculate the real-time fundamental positive sequence capacity of the i th single regulation resource :

[0026] Combined with the real-time power parameters in formula (1), the real-time fundamental positive sequence capacity of the i th single regulation resource output can be obtained according to the power decomposition method :

[0027] (2)

[0028] Step 13: Calculate the real-time unbalanced compensation equivalent capacity of the i th single regulation resource :

[0029] According to the power decomposition method, the equivalent capacity of the i th single regulation resource for treating unbalanced problems is denoted as , then can be further decomposed into three parts: the 1st part of apparent power , the 2nd part of apparent power and the 3rd part of apparent power .

[0030] According to the decomposition relationship of the equivalent capacity of unbalance compensation in the power decomposition method, the real-time equivalent capacity of unbalance compensation of the i-th single adjustment resource is:

[0031] (3)

[0032] Step 14: Calculate the real-time harmonic compensation equivalent capacity of the i-th single adjustment resource :

[0033] According to the power decomposition method, the equivalent capacity of the i-th single adjustment resource for harmonic problem is denoted as , then can be further decomposed into three parts: the 1st part of apparent power , the 2nd part of apparent power and the 3rd part of apparent power .

[0034] According to the decomposition relationship of the equivalent capacity of harmonic compensation in the power decomposition method, the real-time equivalent capacity of harmonic compensation of the i-th single adjustment resource is:

[0035] (4)

[0036] Where, i is the number of single adjustment resource, j is the harmonic number, and n is the maximum harmonic number. , is the 1st harmonic current and voltage of the i-th single adjustment resource.

[0037] Step 2: Calculate the real-time compensated output capacity of each single adjustment resource and the real-time adjustable capacity of each single adjustment resource , including:

[0038] Step 21: According to the equivalent capacity decomposition relationship of each type of compensation in the power decomposition method, the real-time compensated output capacity of the i-th single adjustment resource is calculated from the results of step 1:

[0039] (5)

[0040] Step 22: Assuming that the rated capacity of the i-th single adjustment resource is , the work efficiency is The real-time adjustable capacity of the ith single adjustment resource is calculated from the result of step 21 :

[0041] (6)

[0042] Step 3: Based on the calculation formula of the real-time adjustable capacity of each single adjustment resource , the real-time adjustable capacity of the power quality adjustment resource combination is integrated ;

[0043] It is known that there are m single adjustment resources in the power quality adjustment resource combination, and they are connected in parallel to the power grid. By combining equations (2), (3), (4), and (6), the real-time adjustable capacity of the power quality adjustment resource combination is obtained as :

[0044] (7)

[0045] Where i is the number of single adjustment resources, j is the harmonic number, n is the maximum harmonic number, and m is the total number of single adjustment resources in the power quality adjustment resource combination.

[0046] Embodiment:

[0047] Taking a power quality adjustment resource combination containing 10 single adjustment resources (i.e. m = 10) as an example, the real-time adjustable capacity calculation method proposed in the present application is compared with the general calculation method. In this embodiment, only harmonics of 50 times and below (i.e. n = 50) are considered. Then, under the method of the present application, The calculation expression of the real-time adjustable capacity is specifically:

[0048] (8)

[0049] The general calculation method of real-time adjustable capacity in this embodiment is to proportionally estimate using the total effective value of the output compensation current of each single adjustment resource and the rated current . Then, the calculation expression of the real-time adjustable capacity of the power quality adjustment resource combination calculated by this method is specifically:

[0050] (9)

[0051] ​The adjustable capacity calculation method of the present application is realized by programming, a 10*106 dimensional matrix composed of the effective values of each voltage and current component and basic parameters of the 10 single regulating resources is defined as the calculation data matrix, wherein the i-th row data (i.e. the calculation data of the i-th single regulating resource) is arranged as follows:

[0052] (10)

[0053] wherein, , is the 50th harmonic current and voltage of the i-th single regulating resource.

[0054] It is assumed that each single regulating resource in the combination participates in the fundamental compensation and harmonic compensation (mainly including 3rd, 7th, 11th, 13th and 35th harmonic compensation) of the power grid, and the total rated capacity of the power quality regulating resource combination under different operating conditions (condition 1-condition 5) is simulated by modifying the compensated output current value or rated parameter of each single regulating resource. Figure 3 The total rated capacity of the power quality regulating resource combination under different operating conditions in the simulation is as follows: 1, condition 1: 1.52356 MVar; 2, condition 2: 1.3981 MVar (modify the rated parameter); 3, condition 3: 1.69 MVar (modify the rated parameter); 4, condition 4: 1.52356 MVar (modify the compensation current value); 5, condition 5: 1.52356 MVar (modify the compensation current value).

[0055] The comparison chart of the simulation calculation results is shown in Figure 3 . It can be seen from the comparison of the calculation results that the results estimated by the general calculation method are smaller and it is difficult to accurately evaluate the real-time adjustable capacity of the power quality regulating resource combination. The calculation method proposed by the present application considers the fundamental positive sequence capacity, unbalanced compensation capacity and harmonic compensation capacity in detail, rather than estimation, and has better accuracy, so as to fully evaluate the real-time adjustable capacity of the power quality regulating resource combination and realize the optimal configuration of the resource combination.

Claims

1. A method for real-time adjustable capacity calculation of power quality regulation resource portfolio, characterized in that, The method comprises the following steps: Step 1: obtaining and solving real-time power parameters required for m single adjustment resource calculation, based on a power decomposition method, decomposing and calculating real-time fundamental positive sequence capacity, real-time unbalance compensation equivalent capacity and real-time harmonic compensation equivalent capacity of real-time output of each single adjustment resource; calculating a real-time fundamental positive sequence capacity of the ith single unit regulating resource comprising: In combination with the measured electric quantity parameters, the real-time fundamental positive sequence capacity of the i-th single body adjusting resource output is obtained according to a power decomposition method is: (2) Real-time imbalance compensation equivalent capacity of the ith monomer adjustment resource Decomposed into three parts: 1st part apparent power , 2nd part apparent power , and 3rd part apparent power ; Real-time harmonic compensation equivalent capacity of the ith monomer regulating resource Decomposed into three parts: 1st part apparent power , 2nd part apparent power , and 3rd part apparent power ; Step 2: calculating real-time compensated output capacity of each single adjustment resource and real-time adjustable capacity of each single adjustment resource; According to the equivalent capacity decomposition relationship of various compensations in the power decomposition method, the real-time compensated output capacity of the i th single body regulation resource is calculated by the real-time fundamental positive sequence capacity, the real-time unbalance compensation equivalent capacity and the real-time harmonic compensation equivalent capacity of the i th single body regulation resource in step 1 : (5) Step 3: based on a calculation formula of real-time adjustable capacity of each single adjustment resource, integrating to obtain real-time adjustable capacity of the power quality adjustment resource combination.

2. The method of claim 1, wherein, The step 1 comprises: Step 11: obtaining and solving various real-time power parameters: Based on the power decomposition method, in a three-phase three-wire system, for the i th single adjustment resource, the following power parameters are calculated according to the voltage and current measurement data: (1) Wherein, i is the monomer adjustment resource number, j is the harmonic number, n is the maximum harmonic number, Respectively, the i th monomer adjustment resource real-time output j harmonic current effective value, j harmonic voltage effective value, non-base wave current total effective value, non-base wave voltage total effective value; Respectively, the i th monomer adjustment resource real-time output j harmonic current effective value, j harmonic voltage effective value, non-base wave current total effective value, non-base wave voltage total effective value; Respectively, the i th monomer adjustment resource real-time output j harmonic current effective value, j harmonic voltage effective value, non-base wave current total effective value, non-base wave voltage total effective value; 3. The method for calculating the real-time adjustable capacity of power quality regulation resource combination according to claim 2, characterized in that, According to the decomposition relationship of the unbalance compensation equivalent capacity in the power decomposition method, the simultaneous equation (1) obtains the real-time unbalance compensation equivalent capacity of the ith single body adjustment resource is: (3)。 4. The method for calculating the real-time adjustable capacity of power quality regulation resource combination according to claim 3, characterized in that, According to the decomposition relationship of the harmonic compensation equivalent capacity in the power decomposition method, the simultaneous equation (1) is obtained to get the real-time harmonic compensation equivalent capacity of the ith single body adjustment resource is: (4) , 1st harmonic current, voltage to regulate resource for ith monomer.

5. The method for calculating the real-time adjustable capacity of power quality regulation resource combination according to claim 4, characterized in that, The step 2 further comprises: Step 22: assuming the rated capacity of the ith single adjustment resource is , the work efficiency is , the real-time compensable output capacity of the ith single adjustment resource is , the real-time adjustable capacity of the ith single adjustment resource is calculated as : (6)。 6. The method for calculating the real-time adjustable capacity of power quality regulation resource combination according to claim 5, characterized in that, The step 3 comprises: There are m monomer regulation resources in the known combination, and they are connected to the power grid in parallel. The simultaneous equations (2), (3), (4), and (6) are integrated to obtain the real-time adjustable capacity of the power quality regulation resource combination is: (7) Wherein, i is the single adjustment resource number, j is the harmonic number, n is the maximum harmonic number, and m is the total number of single adjustment resources in the power quality adjustment resource combination.

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