CN105514987A - 10kV Distribution Line Distributed Photovoltaic Capacity Constant Method and System - Google Patents

Abstract

The invention relates to a 10kV distribution line distributed photovoltaic constant volume method and a system, wherein the method comprises the following steps: acquiring characteristic parameters of an object line; selecting a characteristic parameter of a corresponding ground state line according to the type of the object line, and performing per-unit on the characteristic parameter of the object line to obtain a per-unit value parameter; obtaining the terminal photovoltaic limit capacity absorption ratio of the object line according to the per unit value parameter and a line terminal photovoltaic limit capacity absorption ratio constant volume formula corresponding to the type of the object line; correcting the terminal photovoltaic limit capacity consumption ratio according to the actual access position information of the distributed photovoltaic in the object line and the type of the object line to obtain the consumable photovoltaic limit capacity ratio of the object line; and obtaining the consumable photovoltaic limit capacity of the object line according to the total capacity of the distribution transformer of the object line and the consumable photovoltaic limit capacity ratio. The method has guiding significance for the constant volume problem of the distributed photovoltaic access power distribution network.

Description

10kV Distribution Line Distributed Photovoltaic Capacity Constant Method and System

technical field

The invention relates to the technical field of capacity stabilization of distributed power sources connected to distribution networks, in particular to a distributed photovoltaic capacity stabilization method and system for 10kV power distribution lines.

Background technique

With the gradual depletion of fossil energy and the gradual enhancement of social environmental protection awareness, new energy is becoming more and more active in the public's field of vision as an alternative energy source, and photovoltaic power generation has been widely distributed due to its wide resource distribution, less pollution, and renewable characteristics. Favored by people, it is a kind of renewable energy with broad development prospects, and it has become one of the new energy sources with the highest utilization rate. In the power grid, especially the medium and low voltage distribution network, the proportion of photovoltaic power generation is rising rapidly. According to the latest announcement by the National Energy Administration, in 2014 alone, the installed capacity of photovoltaic power generation within the business scope of China Southern Power Grid Corporation reached 280,000 kilowatts, of which photovoltaic power plants were 120,000 kilowatts, and distributed 160,000 kilowatts. Jiangsu, Zhejiang and Guangdong have accumulated distributed grid-connected The capacity is the largest, reaching 700,000 kilowatts, 460,000 kilowatts and 440,000 kilowatts respectively.

However, according to the current relevant technical regulations on distributed energy access, the total capacity of distributed power should not exceed 25% of the maximum load in the upper-level transformer power supply area in principle. If strictly implemented in accordance with this technical regulation, the distributed photovoltaic capacity that can be accommodated by the current power distribution lines will be very limited. Due to the maturity of distributed photovoltaic technology and the attention and support of policies around the world, overly conservative technical regulations cannot adapt to the trend of large-scale photovoltaic grid connection.

At present, the main method of distributed power optimization planning research is to first mathematically model the distribution network, and then solve the model through modern heuristic algorithms such as genetic algorithm and particle swarm optimization according to different optimization objectives. These methods will face the dilemma of complex modeling, difficult or even impossible solution in practical engineering.

Contents of the invention

Based on this, in order to solve the problems in the prior art, the present invention provides a 10kV power distribution line distributed photovoltaic capacity constant method and system, by collecting the characteristic parameters of the 10kV power distribution line, it is possible to accurately obtain the voltage constraints of the line It can accommodate the limit capacity of photovoltaics.

In order to achieve the above purpose, the embodiment of the present invention adopts the following technical solutions:

A 10kV distribution line distributed photovoltaic constant capacity method, comprising the following steps:

Obtain the characteristic parameters of the object line;

Selecting the characteristic parameter of the corresponding ground state circuit according to the type of the object circuit, performing per-unit transformation on the characteristic parameter of the object circuit, and obtaining the per-unit value parameter;

According to the per unit value parameter and the line end photovoltaic limit capacity consumption ratio constant formula corresponding to the type of the target line, the terminal photovoltaic limit capacity consumption ratio of the target line is obtained;

According to the actual access location information of distributed photovoltaics in the target line and the type of the target line, the terminal photovoltaic limit capacity absorptive ratio is corrected to obtain the accommodable photovoltaic limit capacity ratio of the target line;

According to the total capacity of the distribution transformer of the object line and the ratio of the absorbable photovoltaic limit capacity, the absorbable photovoltaic limit capacity of the object line is obtained

And a 10kV distribution line distributed photovoltaic constant capacity system, including:

A feature parameter acquisition module, configured to acquire feature parameters of the object line;

The per-unit conversion module is used to select the characteristic parameter of the corresponding ground-state circuit according to the type of the target circuit, perform per-unit conversion on the characteristic parameter of the target circuit, and obtain the per-unit value parameter;

The accommodation ratio calculation module is used to obtain the terminal photovoltaic limit capacity accommodation of the object line according to the per unit value parameter and the line end photovoltaic limit capacity accommodation ratio constant formula corresponding to the type of the object line Compare;

A correction module, configured to correct the terminal photovoltaic limit capacity absorptive ratio according to the actual access location information of distributed photovoltaics in the target line and the type of the target line, so as to obtain the accommodative ratio of the target line Photovoltaic limit capacity ratio;

A constant capacity calculation module, configured to obtain the accommodable limit capacity of photovoltaics of the target line according to the total capacity of the distribution transformer of the target line and the ratio of the accommodable limit capacity of photovoltaics.

The present invention is based on a typical ground state line as a reference. After obtaining the characteristic parameters of the target line, it can accurately obtain the maximum distributed photovoltaic capacity that can be connected to the 10kV power distribution line under the condition of ensuring the safety of voltage operation, so as to provide a reference for the line. Distributed photovoltaic configuration provides quantitative reference. The technical solution provided by the invention is easy to implement, and has guiding significance for the problem of constant capacity of distributed photovoltaics connected to distribution networks.

Description of drawings

Fig. 1 is the schematic flow chart of the 10kV power distribution line distributed photovoltaic constant capacity method in one embodiment of the present invention;

Fig. 2 is a simplified 10kV power distribution line model containing distributed photovoltaics in the embodiment of the present invention;

Fig. 3 is the specific flow diagram of the 10kV distribution line distributed photovoltaic constant capacity method of the present invention in implementation;

Fig. 4 is a schematic structural diagram of an embodiment of the distributed photovoltaic constant capacity system for 10kV power distribution lines of the present invention.

detailed description

The content of the present invention will be further described in detail below in conjunction with preferred embodiments and accompanying drawings. Apparently, the embodiments described below are only used to explain the present invention, not to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention. It should be noted that, for the convenience of description, only parts related to the present invention are shown in the drawings but not all content.

Fig. 1 is a schematic flow chart of an embodiment of the distributed photovoltaic capacity constant method for 10kV distribution lines of the present invention. The distributed photovoltaic capacity constant method for 10kV power distribution lines in this embodiment can be executed by a software system. As shown in Figure 1, the distributed photovoltaic capacity constant method for 10kV distribution lines in this embodiment includes the following steps:

Step S110, acquiring characteristic parameters of the target line;

The target line refers to the line to be connected to distributed photovoltaics. The characteristic parameters of the target line can be used for the distributed photovoltaic capacity of the target line. In this embodiment, the characteristic parameters include the length of the main line, the area of the main line diameter, Substation 10kV bus voltage, minimum load average load rate, line power factor and average capacity of distribution transformers are analyzed and explained below.

Figure 2 shows a simplified 10kV distribution line model with distributed photovoltaics, including a 10kV substation, a 10kV feeder, a distributed photovoltaic power source and a load node. Taking the 10kV substation bus as the balance node, the power transmitted through the line is P+jQ, the line impedance is R+jX, the terminal load power is P _L +jQ _L , and the output of distributed photovoltaics is P ₀ +jQ ₀ .

After the distributed photovoltaic is connected, the power transmitted by the line is:

$\left\{\begin{array}{c}\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; L</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}\\ \mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; L</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}\end{array}\right.$

Neglecting the transverse component of the voltage drop, the voltage loss on the line is:

$\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; V</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Q</span>}\mathrm{<span\; class="notranslate">\; x</span>}}{{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}$

In the above formula, R and X are the resistance and reactance of the distribution line respectively, and V ₀ is the bus voltage of the 10kV substation.

The voltage at the end of the line is the difference between the busbar voltage of the 10kV substation and the line loss voltage, namely:

$\mathrm{<span\; class="notranslate">\; V</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; V</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; P</span>}\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; Q</span>}\mathrm{<span\; class="notranslate">\; x</span>}}{{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}$

From the above derivation process, it can be seen that the factors affecting the node voltage V of the distribution line are:

V ₀ , specifically the voltage amplitude of the previous node, can be understood as the bus voltage of 10kV substation by extension;

R and X, that is, the impedance of the distribution line, specifically including the length and diameter area of the line;

P and Q are specifically related to _PL , Q _L , P ₀ and Q _0. When P ₀ and Q ₀ are research variables, P and Q are specifically reflected in load rate and power factor.

In addition, since the power load is generally connected to the 10kV distribution line through the distribution transformer, the loss of the distribution transformer will also affect the line voltage distribution due to the influence of the transmission power. At present, the loss of distribution transformers is mainly related to capacity. Generally speaking, distribution transformers with larger capacities have smaller losses and better energy-saving effects, while those with smaller capacities are the opposite.

Based on the above analysis, it can be seen that the distribution line node voltage is related to the length of the line, wire diameter area, load rate, power factor, 10kV substation bus voltage and the capacity of the distribution transformer. Therefore, in this embodiment, for the object The distributed photovoltaic capacity of the line is determined, and the characteristic parameters of the target line are selected as the trunk length of the target line, the trunk line diameter area, the 10kV bus voltage of the substation, the minimum load average load rate, the line power factor and the average capacity of the distribution transformer.

Step S120, select the characteristic parameter of the corresponding ground state line according to the type of the target line, perform per-unit transformation on the characteristic parameter of the target line, and obtain the per-unit value parameter;

Considering the large difference in electrical characteristics between urban lines and rural lines, urban lines generally have the characteristics of many cable lines, large wire diameters, small power supply radius, heavy loads, and large transformer capacity; while rural lines are basically overhead lines with relatively small wire diameters. Small, large power supply radius, light load and small transformer capacity. Therefore, in this embodiment, typical lines are classified according to urban cable lines and rural overhead lines, and object lines are divided into two types: cable lines and overhead lines.

Per-unitization is a commonly used numerical processing method in power system analysis and engineering calculation. In this embodiment, the ground state line corresponding to the type of the target line is selected, and the characteristic parameters of the ground state line are used as the reference value. The characteristic parameters are per unitized to obtain per unit value parameters. The per unit value parameter represents the relative value of each physical quantity and parameter.

In an optional implementation manner, if the type of the object line is a cable line, the characteristic parameters of the ground state line include:

The main line length is 4.0 kilometers, the main line diameter area is 240 square millimeters, the voltage of the 10kV busbar in the substation is 10.3 volts, the average load rate of the minimum load is 35%, the power factor of the line is 0.93, and the average capacity of the distribution transformer is 630 kVA .

In another optional implementation manner, if the type of the object line is an overhead line, the characteristic parameters of the ground state line include:

The trunk length of the line is 10.0 kilometers, the trunk diameter area is 185 square millimeters, the voltage of the 10kV bus in the substation is 10.3 volts, the average load rate of the minimum load is 35%, the power factor of the line is 0.88, and the average capacity of the distribution transformer is 200 kVA .

Select the characteristic parameter of the corresponding ground state line according to the type of the target line, then the characteristic parameter of the ground state line can be used as a reference value, and the characteristic parameter of the target line can be per unitized to obtain the per unit value parameter.

Step S130, according to the per unit value parameter and the line end photovoltaic limit capacity consumption ratio constant formula corresponding to the type of the target line, obtain the terminal photovoltaic limit capacity consumption ratio of the target line;

The consumption ratio of photovoltaic limit capacity at the end of the line refers to the ratio of the maximum distributed photovoltaic capacity that can be connected to the 10kV distribution line to the total capacity of the distribution transformer of the 10kV distribution line under the premise of ensuring that the node voltage does not exceed the upper limit. The type of the target line is different, and the selected formula of the photovoltaic limit capacity consumption ratio at the end of the line is also different. In an optional implementation, if the type of the target line is a cable line, the photovoltaic limit capacity consumption ratio of the line end The constant volume formula is:

y＝C ₁ -ax ₁ +bx ₂ -cx ₃ +dx ₄ -ex ₅ -fx ₆ (1)

In the formula (1), x ₁ is the per unit value parameter of the trunk length of the line, x ₂ is the per unit value parameter of the trunk line diameter area, x ₃ is the per unit value parameter of the 10kV bus voltage of the substation, and x ₄ is the minimum load average The per unit value parameter of the load rate, x ₅ is the per unit value parameter of the line power factor, x ₆ is the per unit value parameter of the average capacity of the distribution transformer; a, b, c, d, e, f are the per unit value parameters respectively The sensitivity coefficient of the value parameter; C ₁ is the correction coefficient; y is the photovoltaic limit capacity consumption ratio at the end of the line.

In another optional implementation, if the type of the object line is an overhead line, the photovoltaic limit capacity consumption ratio constant formula at the end of the line is:

y＝C ₁ -ax ₁ +bx ₂ -cx ₃ +dx ₄ -ex ₅ +fx ₆ (2)

In the formula (2), x ₁ is the per unit value parameter of the trunk length of the line, x ₂ is the per unit value parameter of the trunk line diameter area, x ₃ is the per unit value parameter of the 10kV bus voltage of the substation, and x ₄ is the minimum load average The per unit value parameter of the load rate, x ₅ is the per unit value parameter of the line power factor, x ₆ is the per unit value parameter of the average capacity of the distribution transformer; a, b, c, d, e, f are the per unit value parameters respectively The sensitivity coefficient of the value parameter; C ₁ is the correction coefficient; y is the photovoltaic limit capacity consumption ratio at the end of the line.

According to the type of the target line, select the corresponding fixed capacity formula of the photovoltaic limit capacity consumption ratio at the end of the line, and enter the per unit value parameter, and then the terminal photovoltaic limit capacity consumption ratio of the target line can be obtained.

Step S140, according to the actual access position information of distributed photovoltaics in the target line and the type of the target line, correct the terminal photovoltaic limit capacity consumption ratio to obtain the accommodable photovoltaic limit of the target line capacity ratio;

After obtaining the terminal photovoltaic limit capacity consumption ratio of the target line, according to the type of the target line, and then according to the actual access location information of distributed photovoltaics in the target line, the terminal photovoltaic limit capacity consumption ratio of the target line is corrected. In an optional implementation manner, when making corrections, the target line is divided into several segments according to the length of the trunk, and the actual access location information of distributed photovoltaics is the segment where distributed photovoltaics access the target line information. Preferably, the target line can be divided into three sections according to the length of the trunk. When the segment information of the distributed photovoltaic access target line is different, the correction coefficient _C2 used is also different, that is, when the distributed photovoltaic is in different segment positions When accessing, different correction coefficients _C2 are used to correct the terminal photovoltaic limit capacity absorption ratio of the target line. _The specific values of C2 are as follows:

If the type of the object line is a cable line, take the value in the following table:

The location of distributed photovoltaic 0～1/2 stage 1/2～3/4 stage 3/4～end Correction factor C ₂ 1.65 1.27 0.95

If the type of the object line is an overhead line, take the value in the following table:

The location of distributed photovoltaic 0～1/2 stage 1/2～3/4 stage 3/4～end Correction factor C ₂ 1.5 1.22 0.95

In an optional implementation manner, the accommodable limit photovoltaic capacity ratio of the target line can be obtained by multiplying the correction coefficient C ₂ by the terminal photovoltaic limit capacity ratio of the target line.

Step S150, obtaining the accommodable limit photovoltaic capacity of the target line according to the total capacity of the distribution transformer of the target line and the accommodable limit photovoltaic capacity ratio.

The absorptable photovoltaic limit capacity of the target line specifically refers to the maximum distributed photovoltaic capacity that the target line can access under the constraint that the node voltage does not exceed the upper limit. Multiply the absorbable photovoltaic limit capacity ratio of the object line with the total capacity of the distribution transformer of the object line to obtain the absorbable photovoltaic limit capacity of the object line.

Fig. 3 is a schematic flow chart of the implementation of the distributed photovoltaic capacity constant method for 10kV distribution lines of the present invention. The following takes a certain 10kV cable line in the southern region as an example to illustrate the implementation process and beneficial effects of the present invention.

The characteristic parameters of the 10kV cable line are as follows: the trunk length of the line is 5.6km, the diameter area of the trunk line is 300mm ² , the voltage of the 10kV busbar of the substation is 10.5kV, the average load rate of the minimum load is 40%, the power factor of the line is 0.95, and the power distribution The average capacity of the transformer is 486kVA.

Then select the characteristic parameters of the ground state line relative to the cable line, carry out per-unit transformation on the characteristic parameters of the cable line, and obtain the per-unit value parameters as follows:

_{x1 x2 x3 x4 x5 x6} 1.400 1.250 1.019 1.143 1.022 0.771

Then, according to the per unit value parameter of the target line and the photovoltaic limit capacity consumption ratio constant formula at the end of the line corresponding to the type of the target line, the terminal photovoltaic limit capacity consumption ratio of the target line is calculated. Since the target line is a cable line, formula (1) is selected, and the per unit value parameters x ₁ , x ₂ , x ₃ , x ₄ , x ₅ , and x ₆ are substituted into formula (1) for calculation. In the present embodiment, the values of the sensitivity coefficients a, b, c, d, e, and f in the formula (1) are respectively 0.141, 0.337, 7.161, 0.323, 1.822, 0.238; the correction coefficient C is _9.323 . The terminal photovoltaic limit capacity consumption ratio of the cable line is obtained through calculation, as follows:

y＝C ₁ -ax ₁ +bx ₂ -cx ₃ +dx ₄ -ex ₅ -fx ₆

=9.323-0.141×1.400+0.337×1.250-7.161×1.019

+0.323×1.143-1.822×1.022-0.238×0.771

=0.57

Then, according to the actual access position of distributed photovoltaics, the terminal photovoltaic limit capacity consumption ratio is corrected. In this embodiment, the distributed photovoltaic access position of the target line is 4.1 km away from the feeder head end, that is, the distributed photovoltaic is located in the 1/2 to 3/4 section of the line, so the corresponding correction coefficient C ₂ is selected as 1.27, and the The correction coefficient C ₂ is multiplied by the terminal photovoltaic limit capacity consumption ratio calculated above, and the corrected photovoltaic limit capacity ratio of the target line can be obtained as 0.72. Then the above results are restored by the total capacity of the distribution transformer of the target line, that is, the absorbable photovoltaic limit capacity ratio of the target line 0.72 is multiplied by the total capacity of the distribution transformer of the target line 11175kVA, and the absorbable photovoltaic limit of the target line is obtained The capacity is 8046kW.

The target line is modeled and simulated on the distribution network power flow calculation software. By gradually increasing the connected distributed photovoltaic capacity and performing power flow calculation, the target line can be connected under the premise of ensuring that the node voltage does not exceed the upper limit. The accommodative ratio of the actual photovoltaic limit capacity is 0.75, which is slightly higher than the accommodable photovoltaic limit capacity ratio calculated by the technical solution of the present invention, and there is still a certain margin under the premise of ensuring safety, which meets the needs of actual engineering planning .

In addition, a 10kV overhead line in the southern region was selected as the target line, and the characteristic parameters of the target line were collected as follows: the trunk length of the line is 18.74km, the diameter area of the trunk line is 150mm ² , the voltage of the 10kV busbar in the substation is 10.5kV, and the minimum load The average load rate is 50%, the line power factor is 0.90, and the average capacity of the distribution transformer is 250kVA.

The characteristic parameters of the target line are per unitized with the characteristic parameters of the ground state line as the reference value, and the per unit value parameters of the target line are obtained as follows:

_{x1 x2 x3 x4 x5 x6} 1.874 0.811 1.019 1.429 1.023 1.250

Then, according to the per unit value parameter of the target line and the photovoltaic limit capacity consumption ratio constant formula at the end of the line corresponding to the type of the target line, the terminal photovoltaic limit capacity consumption ratio of the target line is calculated. Since the object line is an overhead line, formula (2) is selected for calculation. In the present embodiment, the values of the sensitivity coefficients a, b, c, d, e, and f in the formula (1) are respectively 0.023, 0.157, 2.397, 0.261, 0.454, and 0.010; the value _of the correction coefficient C is 2.825 . Then, substitute the per unit value parameters x ₁ , x ₂ , x ₃ , x ₄ , x ₅ , and x ₆ into the formula (2), and obtain the terminal photovoltaic limit capacity consumption ratio of the overhead line through calculation, as follows:

y＝C ₁ -ax ₁ +bx ₂ -cx ₃ +dx ₄ -ex ₅ +fx ₆

=2.825-0.023×1.874+0.157×0.811-2.397×1.019

+0.261×1.429-0.454×1.023-0.010×1.250

=0.39

Then, according to the actual access location information of distributed photovoltaics, the terminal photovoltaic limit capacity consumption ratio is corrected. The distributed photovoltaic access position of the target line is 9.3km away from the head end of the feeder, that is, the distributed photovoltaic is located in the 0~1/2 section of the line, so the corresponding correction coefficient C ₂ is selected as 1.5, and the correction coefficient C ₂ is calculated with the above calculation Multiplying the terminal photovoltaic limit capacity consumption ratio of the target line after correction, the absorbable photovoltaic limit capacity ratio of the target line is 0.59. Then the above results are restored by the total capacity of the distribution transformer of the target line, that is, the absorbable photovoltaic limit capacity ratio of the target line 0.59 is multiplied by the total capacity of the distribution transformer of the target line 9000kVA, and the absorbable photovoltaic limit of the target line is obtained The capacity is 5310kW.

On the distribution network power flow calculation software, the object line is modeled and simulated. By gradually increasing the connected distributed photovoltaic capacity and performing power flow calculation, the object line can be connected under the premise of ensuring that the node voltage does not exceed the upper limit. The absorptive ratio of the actual photovoltaic limit capacity is 0.60, which is slightly higher than the accommodable photovoltaic limit capacity ratio calculated by the technical solution provided by the present invention. There is still a certain margin under the premise of ensuring safety, which can also meet the actual engineering needs.

Based on the above contents, it can be seen that by adopting the distributed photovoltaic constant capacity method of the 10kV distribution line of the present invention, the calculated absorbable photovoltaic limit capacity is very close to and slightly smaller than the actual photovoltaic limit capacity of the line. Therefore, based on the typical ground state line as a reference, the technical solution of the present invention can accurately obtain the maximum distributed capacity that can be connected to the 10kV distribution line under the condition of ensuring the safety of voltage operation, so as to provide the distributed photovoltaic system for the line. The configuration provides a quantitative reference.

According to the above-mentioned 10kV power distribution line distributed photovoltaic constant capacity method of the present invention, the present invention also provides a 10kV power distribution line distributed photovoltaic constant capacity system. The type photovoltaic constant capacity system will be described in detail.

Fig. 4 is a schematic structural diagram of an embodiment of the distributed photovoltaic constant capacity system for 10kV power distribution lines of the present invention. As shown in Figure 4, the 10kV distribution line distributed photovoltaic constant capacity system in this embodiment includes:

A feature parameter acquisition module 100, configured to acquire feature parameters of the target line;

The per-unit conversion module 200 is configured to select the characteristic parameter of the corresponding ground-state line according to the type of the target line, perform per-unit conversion on the characteristic parameter of the target line, and obtain the per-unit value parameter;

The absorption ratio calculation module 300 is used to obtain the terminal photovoltaic limit capacity consumption of the object line according to the per unit value parameter and the line end photovoltaic limit capacity absorption ratio constant formula corresponding to the type of the object line. Nabi;

The correction module 400 is used to correct the terminal photovoltaic limit capacity consumption ratio according to the actual access location information of distributed photovoltaics in the target line and the type of the target line, so as to obtain the dissimilarity ratio of the target line. Nano-photovoltaic limit capacity ratio;

The constant capacity calculation module 500 is configured to obtain the accommodable limit capacity of photovoltaics of the target line according to the total capacity of the distribution transformer of the target line and the ratio of the limit capacity of photovoltaics that can be accommodated.

In an optional implementation, the characteristic parameters include line trunk length, trunk line diameter area, substation 10kV bus voltage, minimum load average load rate, line power factor and distribution transformer average capacity.

In an optional implementation manner, the actual access location information of distributed photovoltaics is segment information of distributed photovoltaics accessing the target line.

The above-mentioned 10kV distribution line distributed photovoltaic capacity constant system can implement the 10kV power distribution line distributed photovoltaic capacity constant method provided by the embodiment of the present invention, and has corresponding functional modules and beneficial effects for executing the method.

The various technical features of the above-mentioned embodiments can be combined arbitrarily. For the sake of concise description, all possible combinations of the various technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (10)

1. a 10kV distribution line distributed photovoltaic constant volume method, is characterized in that, comprise the steps:

Obtain the characteristic parameter of object circuit;

According to the characteristic parameter of ground state circuit corresponding to the type selecting of described object circuit, standardization is carried out to the characteristic parameter of described object circuit, obtain perunit value parameter;

Dissolve than constant volume formula according to described perunit value parameter and the line end photovoltaic power-carrying corresponding with the type of described object circuit, the end photovoltaic power-carrying obtaining described object circuit is dissolved ratio;

According to the actual accessing position information of distributed photovoltaic in described object circuit and the type of described object circuit, described end photovoltaic power-carrying being dissolved than revising, obtaining the dissolved photovoltaic power-carrying ratio of described object circuit;

According to distribution transformer total capacity and described the dissolved photovoltaic power-carrying of photovoltaic power-carrying than the described object circuit of acquisition of dissolving of described object circuit.

2. 10kV distribution line distributed photovoltaic constant volume method according to claim 1, it is characterized in that, described characteristic parameter comprises circuit beam length, backbone footpath area, transformer station 10kV busbar voltage, minimum load Rate of average load, line power factor and distribution transformer average size.

3. 10kV distribution line distributed photovoltaic constant volume method according to claim 2, it is characterized in that, if the type of described object circuit is cable line, then the characteristic parameter of described ground state circuit comprises:

Described circuit beam length is 4.0 kms, described backbone footpath area is 240 square millimeters, and described transformer station 10kV busbar voltage is 10.3 kilovolts, and described minimum load Rate of average load is 35%, described line power factor is 0.93, and described distribution transformer average size is 630 kilovolt-amperes.

4. 10kV distribution line distributed photovoltaic constant volume method according to claim 2, it is characterized in that, if the type of described object circuit is overhead transmission line, then the characteristic parameter of described ground state circuit comprises:

Described circuit beam length is 10.0 kms, described backbone footpath area is 185 square millimeters, and described transformer station 10kV busbar voltage is 10.3 kilovolts, and described minimum load Rate of average load is 35%, described line power factor is 0.88, and described distribution transformer average size is 200 kilovolt-amperes.

5. 10kV distribution line distributed photovoltaic constant volume method according to claim 2, is characterized in that, if the type of described object circuit is cable line, then described line end photovoltaic power-carrying is dissolved than constant volume formula and is:

y＝C ₁-ax ₁+bx ₂-cx ₃+dx ₄-ex ₅-fx ₆

In formula, x ₁for perunit value parameter, the x of described circuit beam length ₂for perunit value parameter, the x of described backbone footpath area ₃for perunit value parameter, the x of described transformer station 10kV busbar voltage ₄for perunit value parameter, the x of described minimum load Rate of average load ₅for perunit value parameter, the x of described line power factor ₆for the perunit value parameter of described distribution transformer average size; A, b, c, d, e, f are respectively the sensitivity coefficient of each perunit value parameter; C ₁for correction factor; Y is that line end photovoltaic power-carrying is dissolved ratio.

6. 10kV distribution line distributed photovoltaic constant volume method according to claim 2, is characterized in that, if the type of described object circuit is overhead transmission line, then described line end photovoltaic power-carrying is dissolved than constant volume formula and is:

y＝C ₁-ax ₁+bx ₂-cx ₃+dx ₄-ex ₅+fx ₆

In formula, x ₁for perunit value parameter, the x of described circuit beam length ₂for perunit value parameter, the x of described backbone footpath area ₃for perunit value parameter, the x of described transformer station 10kV busbar voltage ₄for perunit value parameter, the x of described minimum load Rate of average load ₅for perunit value parameter, the x of described line power factor ₆for the perunit value parameter of described distribution transformer average size; A, b, c, d, e, f are respectively the sensitivity coefficient of each perunit value parameter; C ₁for correction factor; Y is that line end photovoltaic power-carrying is dissolved ratio.

7. 10kV distribution line distributed photovoltaic constant volume method according to claim 1, it is characterized in that, the actual accessing position information of described distributed photovoltaic is the segment information that described distributed photovoltaic accesses described object circuit.

8. a 10kV distribution line distributed photovoltaic constant volume system, is characterized in that, comprising:

Characteristic parameter acquisition module, for obtaining the characteristic parameter of object circuit;

Standardization module, for the characteristic parameter according to ground state circuit corresponding to the type selecting of described object circuit, carries out standardization to the characteristic parameter of described object circuit, obtains perunit value parameter;

Dissolve than computing module, for dissolving than constant volume formula according to described perunit value parameter and the line end photovoltaic power-carrying corresponding with the type of described object circuit, the end photovoltaic power-carrying obtaining described object circuit is dissolved ratio;

Correcting module, for according to the actual accessing position information of distributed photovoltaic in described object circuit and the type of described object circuit, dissolving than revising to described end photovoltaic power-carrying, obtaining the dissolved photovoltaic power-carrying ratio of described object circuit;

Constant volume computing module, for according to the distribution transformer total capacity of described object circuit and described photovoltaic power-carrying of dissolving than the dissolved photovoltaic power-carrying obtaining described object circuit.

9. 10kV distribution line distributed photovoltaic constant volume system according to claim 8, it is characterized in that, described characteristic parameter comprises circuit beam length, backbone footpath area, transformer station 10kV busbar voltage, minimum load Rate of average load, line power factor and distribution transformer average size.

10. 10kV distribution line distributed photovoltaic constant volume system according to claim 8, is characterized in that, the actual accessing position information of described distributed photovoltaic is the segment information that described distributed photovoltaic accesses described object circuit.