User-side self-discipline voltage regulation method and device considering responsibility definition

Abstract

The invention discloses a user side self-discipline voltage regulation method and device considering responsibility definition, and the method comprises the steps: S1, obtaining a unit impedance value and length of a power distribution line by a power grid company, and carrying out the calculation to obtain the total resistance and reactance of the line from a user node to a power supply node; s2, the power grid company sets the reference active power and reactive power of the user according to the power consumption condition of the user and issues the set values to the user side; s3, the user obtains active power and reactive power of the user; s4, the user calculates an active power fluctuation quantity and a reactive power fluctuation quantity of the user; s5, the user calculates an active power fluctuation ratio and a reactive power fluctuation ratio of the user; s6, the user judges whether at least one of the own # imgabs0 # exceeds a reference threshold value or not, if yes, a success rate out-of-limit signal Sig1 is generated, and the step S7 is executed; if not, generating a power non-out-of-limit signal Sig2 and executing the step S3; s7, the user calculates the self-discipline compensation amount required by the user; and S8, the user uses a parallel capacitor, an SVG static var generator and other devices to carry out on-site compensation. According to the invention, the problem that the voltage regulation responsibility sharing is not clear is solved, and the privacy security of the user is also ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of reactive power compensation and voltage regulation in distribution networks, and in particular to a user-side autonomous voltage regulation method and device taking responsibility definition into consideration. Background Art

[0002] In recent years, energy shortage and environmental pollution have become increasingly serious. The penetration rate of units based on renewable energy such as solar energy, wind energy, and biomass energy in the power grid has increased dramatically. The uncertainty and variability of these renewable energy sources have also led to an increase in the voltage volatility of the power system. The difficulty of regulating the grid voltage has gradually increased, and it is particularly important and urgent to take effective and convenient voltage regulation measures. At the voltage regulation strategy level of the distribution network, there has been good development both at home and abroad, which can be mainly divided into three categories: centralized, distributed, and decentralized regulation strategies.

[0003] Centralized control optimizes and coordinates all controllable resources through a central controller, and uses information such as network parameters and operating status to perform centralized calculations to obtain the operation and control plan of the active distribution network. At present, the centralized control architecture requires a large amount of long-distance information interaction between the distribution station and the user. It is difficult for the distribution station to make the control of the nodes far away very fine. More importantly, a large amount of information interaction makes it difficult to ensure the privacy and security of users. Distributed control achieves the control goal by setting up autonomous intelligent agents in the network to iteratively calculate information. This type of architecture often requires information exchange between nodes and continuous iteration of information to make the control more refined. Similarly, this information interaction is also difficult to ensure the privacy and security of users. Decentralized control focuses more on each node itself, does not require global information, only the information of its own node. This type of architecture achieves real-time and rapid response to voltage uncertainty fluctuations through local controllers, and decisions are made directly at the node, and there is basically no privacy violation problem.

[0004] At present, the voltage control structure based on local voltage offset feedback control is mainly used in the decentralized control architecture. This control structure calculates the reactive power compensation amount through the local voltage offset. However, in the distribution network system, the voltage fluctuation of a certain node is not caused by the action of this node alone. The power consumption of other load nodes in the line will also affect the voltage of this node, which leads to the problem that the root cause of voltage offset is unclear and the responsibility for voltage regulation is unclear. Summary of the invention

[0005] In view of the above problems, the present invention provides a user-side autonomous voltage regulation method and device taking responsibility definition into consideration.

[0006] In the first aspect, the technical solution of the present invention provides a user-side self-regulatory voltage regulation method that takes into account the definition of responsibilities. Most of the operations are completed on the user side, and the user basically does not need to provide local information, thereby protecting the user's privacy. At the same time, the method provided by the present invention regulates the voltage based on power fluctuations. Each user is only responsible for the power fluctuations of its own node, and the distribution of voltage regulation responsibilities is also relatively fair. The method includes the following steps:

[0007] Step S1: The power grid company obtains the unit impedance value and length of the distribution line and calculates the total line resistance R from the user node to the power node. m Reactance X m ;

[0008] Step S2: The power grid company sets the user's baseline active power according to the user's power consumption. and reactive power And distribute the set value to the user end;

[0009] Step S3: The user obtains its own active power P mk and reactive power Q mk ;

[0010] Step S4: The user calculates its own active power fluctuation ΔP mk and reactive power fluctuation ΔQ mk ;

[0011] Step S5: The user calculates its own active power fluctuation rate and reactive power fluctuation rate

[0012] Step S6: User determines his / her own Whether at least one of the If yes, then generate a power limit-exceeding signal Sig1 and execute step S7; if no, generate a power limit-free signal Sig2 and execute step S3;

[0013] Step S7: The user calculates the amount of self-discipline compensation required

[0014] Step S8: The user uses shunt capacitors and SVG static VAR generators and other equipment for on-site compensation.

[0015] Furthermore, the active power fluctuation of the mth user at time k in step S4 is and reactive power fluctuation

[0016] Furthermore, in step S5, the active power fluctuation rate of the mth user at time k is and reactive power fluctuation rate

[0017] Furthermore, the self-discipline compensation amount required by the mth user at time k in step S7 is The calculation method is:

[0018]

[0019] In the above formula, U mk is the voltage of the node before regulation of the mth user at time k, Δ mk =b 2 -4ac, where:

[0020] a=R m 2 +X m 2 ;

[0021]

[0022] The reactive power compensation is only related to the user's local power, power fluctuation and line parameters, so each user node compensates itself and is responsible for the voltage fluctuation caused by its own power fluctuation.

[0023] In a second aspect, the technical solution of the present invention provides a user-side autonomous voltage regulation device that takes responsibility definition into consideration, including a collection module, a calculation module, and a control module:

[0024] The acquisition module is used to obtain the user's active power P mk and reactive power Q mk ;

[0025] Calculation module for calculating active power according to the reference Reactive power And the active power P obtained by the acquisition module mk , reactive power Q mk Calculate the user's active power fluctuation ΔP mk and reactive power fluctuation ΔQ mk ; Used to calculate the user's active power fluctuation rate based on the power fluctuation amount and reactive power fluctuation rate And judge and Whether it exceeds the reference threshold If yes, a power over-limit signal Sig1 is generated; if no, a power non-over-limit signal Sig2 is generated; used to calculate the self-discipline compensation amount required by the user when receiving the power over-limit signal Sig1 provided by this module

[0026] The control module is used to receive the power limit signal Sig2 provided by the calculation module, according to the compensation amount information provided by the calculation module. Control compensation equipment such as shunt capacitors and SVG static VAR generators to perform compensation;

[0027] In the above modules, the acquisition module is connected to the calculation module and transmits data P to the calculation module. mk , Q mk , and receives the power limit signal Sig2 provided by the calculation module; the calculation module is connected to the control module and transmits data to it

[0028] The present invention uses user self-discipline to perform on-site compensation, offsets the impact of load fluctuations on line voltage drops, effectively suppresses the fluctuation of the voltage difference between the distribution station and the user node, and achieves the goal of basically stabilizing the load voltage of the controlled node. The distribution network reactive power compensation method provided by the present invention requires users to be responsible for the voltage changes caused by their own power fluctuations and perform self-discipline on-site compensation, which not only better solves the problem of unclear sharing of voltage regulation responsibilities, but also protects user privacy and security.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) The present invention does not regulate voltage based on local voltage offset feedback control, but regulates voltage based on local power fluctuation. Each user is only responsible for the power fluctuation of the local node, and there is basically no problem of unclear distribution of voltage regulation responsibilities.

[0031] (2) The present invention requires that most of the voltage regulation process be completed locally by the user, thus avoiding a large amount of information interaction between nodes and protecting the privacy security of the user to a great extent.

[0032] In addition, the invention has a reliable design principle, a simple structure and a very broad application prospect.

[0033] It can be seen that compared with the prior art, the present invention has outstanding substantive features and significant progress, and the beneficial effects of its implementation are also obvious. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0035] Figure 1 A schematic flow chart of a method according to an embodiment of the present invention;

[0036] Figure 2 A schematic block diagram of an apparatus according to an embodiment of the present invention;

[0037] Figure 3 A schematic diagram of an IEEE 37-node active power distribution network provided by an embodiment of the present invention;

[0038] Figure 4 (a) and Figure 4 (b) is a temporal and spatial distribution diagram of voltage before and after the implementation of a method according to an embodiment of the present invention, wherein: Figure 4 (a) is the temporal and spatial distribution diagram of voltage before regulation. Figure 4 (b) Spatiotemporal distribution of voltage after regulation;

[0039] Figure 5 This is a user power distribution diagram before regulation according to an embodiment of the present invention.

[0040] Figure 6 This is a spatiotemporal distribution diagram of user reactive compensation amount according to an embodiment of the present invention. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions 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 only 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 ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0042] Example 1

[0043] like Figure 1 As shown, this embodiment provides a user-side autonomous voltage regulation method considering responsibility definition, including the following steps:

[0044] Step S1: The power grid company obtains the unit impedance value and length of the distribution line and calculates the total line resistance R from the mth user node to the power node. m Reactance X m ;

[0045] Step S2: The power grid company sets the benchmark active power of the mth user according to the user's power consumption. and reactive power And distribute the set value to the user end;

[0046] Step S3: The mth user obtains its own active power P at time k mk and reactive power Q mk ;

[0047] The mth user calculates its own active power fluctuation at time k and reactive power fluctuation

[0048] Step S5: The mth user calculates its own active power fluctuation rate at time k and reactive power fluctuation rate;

[0049] Step S6: The mth user determines his own Whether at least one of the If yes, then generate a power limit-exceeding signal Sig1 and execute step S7; if no, generate a power limit-free signal Sig2 and execute step S3;

[0050] Step S7: The mth user calculates the self-discipline compensation required for himself at time k Where:

[0051]

[0052] Among them, P mk , Q mk , U mk are the active power, reactive power and pre-regulation node voltage of the mth user at time k, ΔP mk , ΔQ mk are respectively the active power fluctuation and reactive power fluctuation of the mth user at time k. In addition, Δ mk =b 2 -4ac, where:

[0053] a=R m 2 +X m 2 ;

[0054]

[0055] Step S8: The mth user uses shunt capacitors and SVG static VAR generators and other equipment for on-site compensation.

[0056] Example 2

[0057] like Figure 2 As shown, this embodiment provides a user-side autonomous voltage regulation device considering responsibility definition, including a collection module, a calculation module and a control module;

[0058] The acquisition module is used to obtain the active power P of the mth user at time k. mk and reactive power Q mk ;

[0059] Calculation module for calculating active power according to the reference Reactive power And the active power P obtained by the acquisition module mk, reactive power Q mk Calculate the active power fluctuation ΔP of the mth user at time k mk and reactive power fluctuation ΔQ mk ; Used to calculate the active power fluctuation rate of the mth user at time k based on the power fluctuation and reactive power fluctuation rate And judge and Whether it exceeds the reference threshold If yes, a power over-limit signal Sig1 is generated; if no, a power non-over-limit signal Sig2 is generated; used to calculate the self-discipline compensation required by the mth user at the kth moment when the power over-limit signal Sig1 provided by this module is received

[0060] The control module is used to receive the power limit signal Sig2 provided by the calculation module, according to the compensation amount information provided by the calculation module. Control compensation equipment such as shunt capacitors and SVG static VAR generators to perform compensation;

[0061] In the above modules, the acquisition module is connected to the calculation module and transmits data P to the calculation module. mk , Q mk , and receives the power limit signal Sig2 provided by the calculation module; the calculation module is connected to the control module and transmits data to it

[0062] Example 3

[0063] like Figure 3 As shown in the figure, it is a schematic diagram of the IEEE 37-node active distribution network. The voltage at the head end of the network structure in the figure is 10kV. There are four different node load types in the distribution network, namely residential, commercial, industrial and agricultural. The present invention uses this as an example to simulate and verify the proposed method; first, the unit impedance value and length of each line are obtained, and the total resistance R of a line to a power node is calculated. m Reactance X m Taking user nodes 727 and 732 as examples, the total line resistance and reactance from these two user nodes to the power supply node 799 are R 1(727) =0.2686Ω、X 1(727) = 0.4561Ω and R 2(732) =0.4231Ω、X 2(732) =0.7623Ω.

[0064] In this embodiment, taking user nodes 727 and 732 as an example, the power grid company sets the benchmark active power and reactive power

[0065] like Figure 4 The figure shows the temporal and spatial distribution of voltage in the entire power distribution network before and after the implementation of the method proposed by the present invention. Figure 4 As can be seen from sub-figure (a), the voltage changes of users in the network fluctuate significantly and need to be regulated. In this embodiment, the threshold Set to 30%.

[0066] like Figure 5 As shown in FIG. 1 , it is a user power distribution diagram before regulation of this embodiment. Before the method is implemented, taking user nodes 727 and 732 as an example, Figure 5 In the time periods of 3:00-5:00 and 21:00-22:00 shown in FIG, the power fluctuation rate of user node 727 is higher than the reference threshold It is necessary to adopt the method proposed by the present invention for self-discipline compensation, and the user does not need to perform self-discipline reactive power compensation in other time periods; Figure 5 In the time periods of 1:00-5:00, 8:00-11:00, 13:00-16:00, and 19:00-23:00 shown in FIG, the power fluctuation rate of the user node 732 is higher than the reference threshold. It is necessary to adopt the method proposed in the present invention to perform self-discipline compensation, and the user does not need to perform self-discipline reactive power compensation in other time periods.

[0067] from Figure 4 As can be seen in sub-figure (b), after the implementation of the method, all users in the network operate within a safe range, and the safety margin of the user node voltage is also improved.

[0068] like Figure 6 As shown in FIG. 1 , it is a spatiotemporal distribution diagram of reactive power compensation of each user in the power distribution network under the implementation of the method. Taking user nodes 727 and 732 as examples, the power fluctuation rate of user node 727 in the time periods of 3:00-5:00 and 21:00-22:00 is higher than the reference threshold, and the power fluctuation rate of user node 732 in the time periods of 1:00-5:00, 8:00-11:00, 13:00-16:00, and 19:00-23:00 is higher than the reference threshold. Therefore, the two nodes perform self-discipline compensation according to the method of the present invention, which can be Figure 6 It can be seen that the reactive power compensation amount borne by the two user nodes in different time periods is different; in other time periods, the power fluctuation rate of the two user nodes does not exceed the reference threshold, so no self-discipline compensation is performed. Figure 6It can be seen that the compensation amount is zero. At 3:00, the compensation amount of user node 727 is 131.73 kVar, while the compensation amount of user node 732 is 255.37 kVar because the power exceeds the threshold more. It can be seen that this method reasonably and effectively defines the different voltage regulation responsibilities between different users in the power grid, and the problem of unclear voltage regulation responsibilities caused by different load power sizes between users has been solved to a certain extent.

[0069] Although the present invention has been described in detail by referring to the accompanying drawings and in combination with the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person of ordinary skill in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions shall be within the scope of the present invention. Any person of ordinary skill in the art may easily think of changes or substitutions within the technical scope disclosed by the present invention, and these shall be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A user-side autonomous voltage regulation method considering responsibility definition, characterized in that: include: Step S1: The power grid company obtains the unit impedance value and length of the distribution line and calculates the total line resistance R from the user node to the power node. m Reactance X m ; Step S2: The power grid company sets the user's baseline active power according to the user's power consumption. and reactive power And send the set value to the user end; Step S3: The user obtains its own active power P mk and reactive power Q mk ; Step S4: The user calculates its own active power fluctuation ΔP mk and reactive power fluctuation ΔQ mk ; Step S5: The user calculates its own active power fluctuation rate and reactive power fluctuation rate Step S6: User determines his / her own Whether at least one of the If yes, then generate a power limit-exceeding signal Sig1 and execute step S7; if no, generate a power limit-free signal Sig2 and execute step S3; Step S7: The user calculates the amount of self-discipline compensation required Step S8: The user uses shunt capacitors and SVG static VAR generators and other equipment for on-site compensation.

2. A user-side autonomous voltage regulation method considering responsibility definition as claimed in claim 1, characterized in that: Active power fluctuation of the mth user at time k in step S4 and reactive power fluctuation 3. A user-side autonomous voltage regulation method considering responsibility definition as claimed in claim 1, characterized in that: Active power fluctuation rate of the mth user at time k in step S5 and reactive power fluctuation rate 4. A user-side autonomous voltage regulation method considering responsibility definition as claimed in claim 1, characterized in that: The self-discipline compensation amount required by the mth user at time k in step S7 The calculation method is: In the above formula, U mk is the voltage of the node before regulation of the mth user at time k, Δ mk =b 2 -4ac, where: a=R m 2 +X m 2 The reactive power compensation amount is only related to the user's local power, power fluctuation and line parameters, so each user node compensates itself and is responsible for the voltage fluctuation caused by its own power fluctuation.

5. A user-side autonomous voltage regulation device considering responsibility definition, characterized in that: Including acquisition module, calculation module and control module: The acquisition module is used to obtain the user's active power P mk and reactive power Q mk ; Calculation module for calculating active power according to the reference Reactive power And the active power P obtained by the acquisition module mk , reactive power Q mk Calculate the user's active power fluctuation ΔP mk and reactive power fluctuation ΔQ mk ; Used to calculate the user's active power fluctuation rate based on the power fluctuation amount and reactive power fluctuation rate And judge and Whether it exceeds the reference threshold If yes, a power over-limit signal Sig1 is generated; if no, a power non-over-limit signal Sig2 is generated; used to calculate the self-discipline compensation amount required by the user when receiving the power over-limit signal Sig1 provided by this module The control module is used to receive the power limit signal Sig2 provided by the calculation module, according to the compensation amount information provided by the calculation module. Control compensation equipment such as shunt capacitors and SVG static VAR generators to perform compensation; In the above modules, the acquisition module is connected to the calculation module and transmits data P to the calculation module. mk , Q mk , and receives the power limit signal Sig2 provided by the calculation module; the calculation module is connected to the control module and transmits data to it

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