CN106532729B - It saves ground and coordinates the method that control 220kV collects substation's high voltage bus voltage - Google Patents

Abstract

The present invention relates to a method for provincially coordinated control of the voltage of the high-voltage bus of a 220kV collection substation, including: in the provincial regulation control system, obtaining the voltage adjustment demand of the high-voltage bus of the 220kV collection substation in the collection area of the jth renewable energy station; Calculate the total voltage regulation capacity of all 220kV renewable energy stations in the collection area of the jth renewable energy station; evaluate whether the total voltage regulation capacity is sufficient; if the total voltage regulation capacity is insufficient, calculate the provincial area corresponding to the 220kV collection substation Coordinate the limit value range of reactive power demand at the gateway; the provincial dispatch control system sends the limit value range to the local dispatch control system, and the local dispatch control system controls reactive power equipment to supplement and adjust the 220kV collection substation in the jth renewable energy station collection area The voltage of the high voltage busbar. The method can effectively realize land-saving coordinated control of the high-voltage busbar voltage of the 220kV converging substation.

Description

Coordinated control method of high-voltage busbar voltage in 220kV converging substation in provinces and regions

technical field

The invention relates to the technical field of voltage control in a renewable energy collection area, in particular to a method for coordinating and controlling the voltage of a high-voltage bus of a 220kV collection substation in an area-saving manner.

Background technique

In recent years, affected by global warming and the energy crisis, the importance of clean energy has become increasingly prominent. Renewable energy such as wind power and photovoltaic power generation has been widely accepted by countries all over the world due to its huge development potential and relatively mature development technology. Pay attention and develop rapidly at an unprecedented speed.

my country adopts a large-scale centralized development model for renewable energy. In renewable energy grid-connected areas, multiple 220kV renewable energy stations (such as wind power stations) and 110kV wind power stations are connected to the grid through a 220kV substation. , this 220kV substation is generally called a wind power collection substation, and the wind power collection substation and all the wind power stations it brings are called a wind power collection area. A typical area is shown in Figure 1. As shown in Figure 1, wind power stations B and C on the high-voltage side of the 220kV collection substation are controlled by the provincial AVC (Automatic Voltage Control) system, and the 220kV collection substation is controlled by the local AVC system.

China's power grid is interconnected and integrated. The traditional AVC system independently controls all levels of power grids. Its control object is only a part of the entire power system, and it lacks coordination from the perspective of the overall power grid. Referring to Figure 1, in the prior art, the AVC system for provincial regulation and the AVC system for local regulation are isolated in control, without coordinated control between each other, any local control will have an impact on the state of the global power grid, especially for some relatively closely related If only independent control is carried out in the power system, control oscillation may occur on the boundary of both sides or the control effect may decline from the perspective of the global power grid, which is not conducive to the stability and quality of the grid voltage.

Contents of the invention

In order to overcome the problems in the related technologies, the present invention provides a land-saving two-level coordinated control method for the voltage of the high-voltage bus of a 220kV converging substation. This method can effectively realize the coordinated control of reactive power and voltage between the 220kV renewable energy station and the 220kV renewable energy collection substation. To adjust the voltage, to avoid reactive power adjustment through switching too many capacitors or reactors in the 220kV renewable energy collection substation; Real-time exchange of information between AVC systems at the ground level, so that the AVC of the ground dispatcher can timely input or remove the reactive equipment (such as capacitors or reactors) in the 220kV renewable energy collection substation, so that the bus voltage in the renewable energy collection area is within the normal range, improving Renewable energy pooling regional grid voltage stability and voltage quality.

According to the first aspect of the embodiments of the present invention, a method for coordinating and controlling the high-voltage busbar voltage of a 220kV collection substation in a provincial area is provided. In each renewable energy station collection area, multiple 220kV renewable energy The substation is connected to the power grid, the 220kV renewable energy stations are controlled by the automatic voltage control system for provincial regulation, and the 220kV converging substation is controlled by the automatic voltage control system for local regulation. When the control cycle comes, the execution is as follows Step: Step S1, in the provincial automatic voltage control system, obtain the voltage regulation demand of the 220kV collection substation high-voltage busbar in the jth renewable energy station collection area, j is a natural number, 1≤j≤renewable in the predetermined area The total number of energy station collection areas; Step S2, calculate the total voltage regulation capacity of all 220kV renewable energy stations in the jth renewable energy station collection area; Step S3, evaluate whether the total voltage regulation capacity meets the required The above-mentioned voltage adjustment demand; step S4, if the total voltage adjustment capacity is enough to adjust the voltage of the high-voltage busbar of the 220kV collection substation in the collection area of the jth renewable energy station, then use the voltage regulation of the 220kV renewable energy station ability to adjust the voltage of the high-voltage bus of the 220kV collection substation in the collection area of the jth renewable energy station; step S5, if the total voltage regulation capacity is not enough to adjust the 220kV collection area of the jth renewable energy station collection area For the voltage of the high-voltage busbar of the substation, calculate the reactive power demand limit range of the provincial coordination gateway corresponding to the 220kV converging substation; step S6, the automatic voltage control system for provincial regulation sends the limit value range to the automatic voltage control system for local regulation In the above, the local automatic voltage control system controls the reactive equipment in the 220kV converging substation in the converging area of the jth renewable energy station, so that in addition to using the total voltage regulation capability in step S2 to adjust the jth renewable energy field In addition to the voltage of the 220kV collection substation high-voltage busbar in the station collection area, the reactive power equipment supplements and adjusts the voltage of the 220kV collection substation high-voltage busbar in the jth renewable energy station collection area; step S7, making j=j+1, Return to step S1.

Preferably, step S1 includes:

In the provincial automatic voltage control system, the voltage regulation demand of the 220kV collection substation high-voltage bus in the jth renewable energy station collection area in the power grid is obtained, namely:

in: In the automatic voltage control system of the provincial power grid, the control target value of the high-voltage bus of the 220kV converging substation is given by the global optimization calculation, is the actual value of the bus voltage, Regulates demand for bus voltage.

Preferably, step S2 includes:

Step S21, receiving the reactive power increase and reactive power reduction from the ith 220kV renewable energy station in the collection area of the jth renewable energy station in real time, and according to the i-th 220kV renewable energy station For the reactive voltage sensitivity of the high-voltage bus of the 220kV converging substation, calculate the voltage increase/decrease adjustment capability of the i-th 220kV renewable energy station to the high-voltage bus of the 220kV converging substation:

in It is the reactive power increase and reactive power reduction that the i-th 220kV renewable energy station in the collection area of the j-th renewable energy station sends in real time, i is a natural number, 1≤i≤j-th renewable energy field The total number of 220kV renewable energy stations in the station collection area;

Step S22, make i=i+1, return to execute step S21;

Step S23, accumulating the voltage increase/decrease adjustment capabilities of all 220kV renewable energy stations in the collection area of the jth renewable energy station:

Preferably, step S3 includes:

Step S31, if Then check and judge:

If Equation (4) holds true, it is determined that the overall voltage increase regulation capacity of all 220kV renewable energy stations in the collection area of the jth renewable energy station is insufficient, where, is the threshold value of voltage regulation, taking 0.5-1.0kV; R _p is the threshold value of coordinated control of renewable energy stations and substations, taking 0.5-0.7;

Step S32, if Then check and judge:

If Equation (5) holds true, it is determined that the overall voltage reduction and regulation capacity of all 220kV renewable energy stations in the jth renewable energy station collection area is insufficient, where, Rp is the threshold value of the current coordinated substation high-voltage bus voltage adjustment, which is 0.5-1.0kV; R _p is the coordinated control threshold value of the renewable energy field station and substation, which is 0.5-0.7.

Preferably, step S5 includes:

Step S51, initialize the reactive power demand limit range of the provincial coordination gateway corresponding to the 220kV converging substation as follows:

in: In order to coordinate the current reactive power value of the provincial and local gateways, In order to save land and coordinate the pass reactive power adjustment dead zone parameter value, take 20-30Mvar;

Step S52, if And in step S301, it is judged that the overall voltage increase and adjustment capacity of all 220kV renewable energy stations in the jth renewable energy station collection area is insufficient, and the reactive power coordination control adjustment requirements of the 220kV collection substation are calculated as follows:

in is the reactive power injection voltage sensitivity of the high-voltage bus of the 220kV collection substation in the collection area of the jth renewable energy station; according to the calculation results, the coordination reactive upper limit of the provincial coordination gateway corresponding to the 220kV collection substation is adjusted as follows:

in, In order to increase the reactive power adjustment capacity of the provincial coordination gateway corresponding to the 220kV collection substation sent by the AVC of the ground dispatching station, the reactive power demand limit of the provincial coordination gateway corresponding to the 220kV collection substation is updated as follows:

Step S53, if And in step S302, it is determined that the overall voltage reduction and regulation capacity of all 220kV renewable energy stations in the collection area of the jth renewable energy station is insufficient, and the reactive power coordination control adjustment requirements of the 220kV collection substation are calculated as follows:

in is the reactive power injection voltage sensitivity of the high-voltage busbar of the 220kV collection substation in the power collection area of the jth renewable energy station; according to the calculation results, the coordination reactive upper limit of the provincial coordination gateway corresponding to the 220kV collection substation is adjusted as follows:

in, In order to reduce the reactive power adjustment capacity of the provincial coordination gateway corresponding to the 220kV collection substation sent by the ground dispatching AVC, update the reactive power demand limit of the provincial coordination gateway corresponding to the 220kV collection substation as:

The provincial adjustment automatic voltage control system will adjust the above-mentioned limit value range It is sent to the automatic voltage control system for local regulation. The automatic voltage control system for local regulation controls the reactive equipment in the 220kV converging substation so that the voltage adjustment capability of the reactive equipment plus the total voltage adjustment capability in step S2 meets the required The above voltage regulation demand.

Preferably, the renewable energy field station may be a wind power station or a photovoltaic power station.

Preferably, every 5 minutes is a control cycle.

To sum up, a method for provincially coordinated control of the high-voltage busbar voltage of 220kV collection substation is provided. In each renewable energy station collection area, multiple 220kV renewable energy stations are connected to the power grid through a 220kV collection substation. Among them, the 220kV renewable energy stations are all controlled by the automatic voltage control system for provincial regulation, and the 220kV converging substation is controlled by the automatic voltage control system for local regulation. When the control period comes, the following steps are performed: step S1, In the provincial automatic voltage control system, obtain the voltage regulation demand of the high-voltage bus of the 220kV collection substation in the jth renewable energy station collection area, j is a natural number, 1≤j≤the renewable energy station collection area in the predetermined area The total number of; Step S2, calculate the total voltage regulation capacity of all 220kV renewable energy stations in the jth renewable energy station collection area; Step S3, evaluate whether the total voltage regulation capacity meets the voltage regulation demand ; Step S4, if the total voltage adjustment capability is sufficient to adjust the voltage of the high-voltage busbar of the 220kV collection substation in the collection area of the jth renewable energy station, use the voltage regulation capability of the 220kV renewable energy station to adjust the jth The voltage of the high-voltage busbar of the 220kV collection substation in the collection area of a renewable energy station; step S5, if the total voltage regulation capability is not enough to adjust the voltage of the high-voltage busbar of the 220kV collection substation in the collection area of the jth renewable energy station , then calculate the reactive power demand limit range of the provincial coordination gateway corresponding to the 220kV converging substation; step S6, the automatic voltage control system of the provincial dispatch sends the limit value range to the automatic voltage control system of the local dispatch, and the automatic voltage control system of the local dispatch The voltage control system controls the reactive power equipment in the 220kV collection substation of the j-th renewable energy station collection area, so that the 220kV collection area of the j-th renewable energy station collection area can be adjusted in addition to using the total voltage adjustment capability in step S2. In addition to the voltage of the high-voltage bus of the converging substation, the reactive equipment additionally adjusts the voltage of the high-voltage bus of the 220kV converging substation in the converging area of the jth renewable energy station; step S7, set j=j+1, and return to step S1. This method can effectively realize the reactive power and voltage coordinated control of the 220kV renewable energy station and the 220kV renewable energy collection substation. When the reactive power adjustment capability of the renewable energy station itself is sufficient, the reactive power of the renewable energy station itself is given priority. To adjust the voltage, avoiding the reactive power adjustment through too many capacitors or reactors switching in the 220kV renewable energy collection substation; Real-time exchange of information between AVC systems, so that the AVC of the ground dispatcher can timely input or remove the reactive power equipment in the 220kV renewable energy collection substation, so that the bus voltage in the renewable energy collection area is within the normal range, and improve the stability of the grid voltage in the renewable energy collection area sex and voltage quality.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description serve to explain the principles of the invention.

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, In other words, other drawings can also be obtained from these drawings without paying creative labor.

Figure 1 is a schematic diagram of the new energy collection regional power grid;

Fig. 2 is a schematic flowchart of a method for coordinated control of high-voltage busbars in a 220kV converging substation provided by an embodiment of the present invention.

Detailed ways

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numerals in different drawings refer to the same or similar elements unless otherwise indicated. The implementations described in the following exemplary examples do not represent all implementations consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with aspects of the invention as recited in the appended claims.

Usually, in each renewable energy station collection area, multiple 220kV renewable energy stations are connected to the grid through a 220kV collection substation, and the 220kV renewable energy stations are controlled by a provincial automatic voltage control system. The 220kV collection substation is controlled by the local automatic voltage control system. In order to avoid large-scale cascading grid disconnection caused by voltage, the reactive power adjustment capability of the renewable energy station itself should be fully utilized in the base state to replace static capacitors or reactors to play the role of voltage support and avoid excessive investment in the base state. Cutting capacitors or reactors results in a large amount of excess reactive power during fault disturbances.

Therefore, the reactive power and voltage coordination principles of renewable energy stations and 220kV collection substations are as follows:

1. Prioritize the use of reactive power regulation capabilities of renewable energy stations in the base state

When the renewable energy station has reactive power regulation capability, the low-voltage reactive power equipment in the 220kV collection substation does not participate in the voltage regulation of the renewable energy station, and the renewable energy and SVC (StaticVar Compensator, static The reactive power adjustment of the reactive power compensator) makes the busbar voltage of the 220kV converging substation within the safe voltage static safe area of the wind power area N-1.

2. When the reactive power adjustment capacity of the renewable energy station is insufficient, use the low-voltage side reactive power equipment in the 220kV converging substation for renewable energy regional voltage regulation

When the reactive power adjustment capacity of the renewable energy station in the renewable energy collection area is insufficient, that is, when the reactive power adjustment capacity in the renewable energy station is lower than a given limit, the low voltage in the 220kV collection substation is switched Reactive equipment, so that the bus voltage in the 220kV collection substation is within the voltage safety limit.

In order to realize the reactive power and voltage coordinated control principle of the above-mentioned renewable energy field station and 220kV collection substation, the present invention proposes and implements a land-saving two-level coordinated control method. As shown in Figure 2, the method for provincially coordinated control of the high-voltage bus voltage of the 220kV converging substation includes the following steps when the control cycle (every 5 minutes is a control cycle) arrives:

Step S1, in the provincial automatic voltage control system, obtain the voltage regulation demand of the 220kV collection substation high-voltage bus in the jth renewable energy station collection area, j is a natural number, 1≤j≤renewable energy field in the predetermined area The total number of station pooling areas. Here, the predetermined area may be, for example, the entire Yunnan Province or a certain area of Yunnan Province.

Step S2, calculating the total voltage regulation capacity of all 220kV renewable energy stations in the collection area of the jth renewable energy station.

Step S3, assessing whether the total voltage regulation capability satisfies the voltage regulation requirement.

Step S4, if the total voltage adjustment capability is sufficient to adjust the voltage of the high-voltage bus of the 220kV collection substation in the collection area of the jth renewable energy station, use the voltage regulation capability of the 220kV renewable energy station to adjust the jth The voltage of the high-voltage busbar of the 220kV collection substation in the collection area of the renewable energy station.

Step S5, if the total voltage adjustment capability is not enough to adjust the voltage of the high-voltage busbar of the 220kV collection substation in the collection area of the jth renewable energy station, calculate the reactive power demand of the provincial coordination gateway corresponding to the 220kV collection substation range of limits.

In step S6, the automatic voltage control system for provincial regulation sends the limit value range to the automatic voltage control system for local regulation. Reactive equipment, so that in addition to using the total voltage adjustment capability in step S2 to adjust the voltage of the 220kV collection substation high-voltage busbar in the collection area of the jth renewable energy station, the reactive equipment supplementary regulation of the jth renewable energy The voltage of the high-voltage bus of the 220kV collection substation in the collection area of the energy station.

Step S7, set j=j+1, return to step S1.

According to an embodiment of the present invention, the above step S1 may specifically include:

In the provincial automatic voltage control system, the voltage regulation demand of the 220kV collection substation high-voltage bus in the jth renewable energy station collection area in the power grid is obtained, namely:

in: In the automatic voltage control system of the provincial power grid, the control target value of the high-voltage bus of the 220kV converging substation is given by the global optimization calculation, is the actual value of the bus voltage, Regulates demand for bus voltage.

According to an embodiment of the present invention, the above step S2 may specifically include:

Step S21, receiving the reactive power increase and reactive power reduction from the ith 220kV renewable energy station in the collection area of the jth renewable energy station in real time, and according to the i-th 220kV renewable energy station For the reactive voltage sensitivity of the high-voltage bus of the 220kV converging substation, calculate the voltage increase/decrease adjustment capability of the i-th 220kV renewable energy station to the high-voltage bus of the 220kV converging substation:

in It is the reactive power increase and reactive power reduction that the i-th 220kV renewable energy station in the collection area of the j-th renewable energy station sends in real time, i is a natural number, 1≤i≤j-th renewable energy field The total number of 220kV renewable energy stations in the station collection area;

Step S22, make i=i+1, return to execute step S21;

Step S23, accumulating the voltage increase/decrease adjustment capabilities of all 220kV renewable energy stations in the collection area of the jth renewable energy station:

According to an embodiment of the present invention, the above step S3 may specifically include:

Step S31, if Then check and judge:

If Equation (4) holds true, it is determined that the overall voltage increase regulation capacity of all 220kV renewable energy stations in the collection area of the jth renewable energy station is insufficient, where, R _p is the threshold value for the current coordinated control of the voltage of the high-voltage bus in the substation, which is 0.5-1.0kV;

Step S32, if Then check and judge:

If Equation (5) holds true, it is determined that the overall voltage reduction and regulation capacity of all 220kV renewable energy stations in the jth renewable energy station collection area is insufficient, where, Rp is the threshold value of the current coordinated substation high-voltage bus voltage adjustment, which is 0.5-1.0kV; R _p is the coordinated control threshold value of the renewable energy field station and substation, which is 0.5-0.7.

According to an embodiment of the present invention, the above step S5 may specifically include:

Step S51, initialize the reactive power demand limit range of the provincial coordination gateway corresponding to the 220kV converging substation as follows:

in: In order to coordinate the current reactive power value of the provincial and local gateways, In order to save land and coordinate the pass reactive power adjustment dead zone parameter value, take 20-30Mvar;

Step S52, if And in step S31, it is judged that the overall voltage increase and regulation capacity of all 220kV renewable energy stations in the collection area of the j-th renewable energy station is insufficient, then the reactive power coordination control adjustment requirements of the 220kV collection substation are calculated as follows:

in is the reactive power injection voltage sensitivity of the high-voltage bus of the 220kV collection substation in the collection area of the jth renewable energy station; according to the calculation results, the coordination reactive upper limit of the provincial coordination gateway corresponding to the 220kV collection substation is adjusted as follows:

in, In order to increase the reactive power adjustment capacity of the provincial coordination gateway corresponding to the 220kV collection substation sent by the automatic voltage control system of the ground dispatching system, update the reactive power demand limit of the provincial coordination gateway corresponding to the 220kV collection substation as follows:

Step S53, if And in step S32, it is determined that the overall voltage reduction and regulation capacity of all 220kV renewable energy stations in the jth renewable energy station collection area is insufficient, then the reactive power coordination control adjustment requirements of the 220kV collection substation are calculated as follows:

in is the reactive power injection voltage sensitivity of the high-voltage busbar of the 220kV collection substation in the power collection area of the jth renewable energy station; according to the calculation results, the coordination reactive upper limit of the provincial coordination gateway corresponding to the 220kV collection substation is adjusted as follows:

in, For the reactive power reduction adjustment capability of the provincial coordination gateway corresponding to the 220kV collection substation sent by the ground dispatching automatic voltage control system, the reactive power demand limit of the provincial coordination gateway corresponding to the 220kV collection substation is updated as follows:

The provincial adjustment automatic voltage control system will adjust the above-mentioned limit value range It is sent to the automatic voltage control system for local regulation. The automatic voltage control system for local regulation controls the reactive equipment in the 220kV converging substation so that the voltage adjustment capability of the reactive equipment plus the total voltage adjustment capability in step S2 meets the required The above voltage regulation demand.

According to an embodiment of the present invention, the renewable energy field station is a wind power station or a photovoltaic power station.

The following is an example to describe the method of the present invention for the land-saving coordinated control of the high-voltage busbar voltage of the 220kV converging substation with reference to FIG. 1 . Figure 1 is a schematic diagram of the new energy collection regional grid architecture of the regional grid. As shown in Figure 1, the provincial AVC system directly controls 220kV wind farm B and 220kV wind farm C; the local AVC system directly controls the 220kV wind power collection substation A. Among them, the current voltage of the high-voltage bus (220kV bus) of the 220kV wind power substation is 229.06kV, and the set voltage is 230.50kV. Each renewable energy station is equipped with SVC (Static Var Compensator, static var compensator).

For the regional power grid shown in Fig. 1, the method for the coordinated control of 220kV pooled substation high-voltage busbar voltage of the present invention, when the control cycle (every 5 minutes is a control cycle) comes, the following steps are performed:

1) In the provincial regulation AVC, obtain the voltage regulation demand of the high-voltage busbar of the 220kV collection substation in the jth wind power collection area in the power grid, namely:

in: In the automatic voltage control system of the provincial power grid, the control target value of the high-voltage bus of the 220kV converging substation is given by the global optimization calculation, is the actual value of the bus voltage, Regulating demand for bus voltage;

2) In the provincial AVC system, the following calculations are performed for each 220kV wind farm in the jth wind power collection area:

2-1) Receive the incremental reactive power sent by wind farms B and C in the collection area in real time and subtractable reactive power And according to the reactive voltage sensitivity of the wind farm to the high-voltage bus of the 220kV wind power collection substation, calculate the voltage increase and decrease adjustment capacity of the wind farm to the high-voltage bus of the 220kV wind power collection substation:

B wind farm: Sensitivity is 0.2, calculated upward adjustable voltage 2.0*0.2=0.4kV and downward adjustable voltage 3.0*0.2=0.6kV;

C wind farm: Sensitivity is 0.2, calculated upward adjustable voltage 2.0*0.2=0.4kV and downward adjustable voltage 2.5*0.2=0.5kV;

2-2) The adjustment capacity of the wind farm B and C to the high-voltage side bus of the main transformer substation of the wind power collection substation is accumulated into the total bus voltage regulation capacity of the wind power collection area:

3) Assess the voltage regulation capability of all wind farms in the wind power collection area, the method is as follows:

Pick R _p =0.6, current (1.44>1.0), then judge whether the following formula holds true: (0.8<1.44*0.6); if this formula is established, it is determined that the wind power voltage increase adjustment capacity in the area is insufficient;

4) According to the evaluation results of the voltage regulation capability of the wind farms participating in the wind power collection area in step 3), calculate the reactive power demand limit range of the 220kV wind power collection substation corresponding to the provincial coordination gateway. The method is as follows:

4-1) Initialize the reactive power demand limit range of the provincial coordination gateway corresponding to the 220kV collection substation,

in:

4-2) Since it has been determined in step 3) that the overall voltage increase and regulation capacity of all wind farms in the current wind power collection area is insufficient, the wind power collection substation needs to coordinate boosting,

4-2-1) According to the previous formula (7), the reactive power coordination control adjustment requirements of the wind power collection substation are calculated as follows:

Pick

4-2-2) According to the previous formula (8), adjust the upper limit of coordination reactive power of the provincial coordination gateway corresponding to the 220kV wind power collection substation:

5) The province-adjusted AVC will set the above-mentioned revised limit value range After being converted into a power factor [0.97, 1.0], it is sent to the ground dispatching AVC system. The local dispatching AVC system controls the 220kV wind power to collect the reactive equipment in the substation (for example, capacitors or reactors in the capacitor/reactor group), The reactive power at the provincial-local coordination gate can meet the requirements of the provincial AVC.

6) Return to step 1), and continue to process the 220kV collection substation in the next wind power collection area until the processing of the 220kV collection substations in all wind power collection areas in the grid is completed.

To sum up, the present invention provides a method for coordinated control of the high-voltage busbar voltage of the 220kV collection substation in a land-saving manner. This method can effectively realize the coordinated control of reactive power and voltage between the 220kV renewable energy station and the 220kV renewable energy collection substation. When the reactive power adjustment capability of the renewable energy station itself is sufficient, the reactive power of the renewable energy station itself is given priority to adjust the voltage, avoiding excessive investment in capacitors in the 220kV renewable energy collection substation; when the renewable energy station itself When the reactive power adjustment capability is insufficient, through the real-time exchange of information between the provincial two-level AVC system, the AVC of the local dispatcher can timely invest in the reactive power equipment in the 220kV renewable energy collection substation, so that the bus voltage in the renewable energy collection area is within the normal range , to improve the voltage stability and voltage quality of the renewable energy collection area grid.

Other embodiments of the invention will be readily apparent to those skilled in the art from consideration of the specification and practice of the invention disclosure herein. This application is intended to cover any modification, use or adaptation of the present invention, these modifications, uses or adaptations follow the general principles of the present invention and include common knowledge or conventional technical means in the technical field not disclosed in the present invention . The specification and examples are to be considered exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

It should be understood that the present invention is not limited to the precise constructions which have been described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.

Claims (7)

1. A method for provincial and local coordination control of high-voltage bus voltage of 220kV convergence substations is characterized in that in each convergence area of renewable energy stations, a plurality of 220kV renewable energy stations are connected into a power grid through a 220kV convergence substation, the 220kV renewable energy stations are controlled by a provincial dispatching automatic voltage control system, the 220kV convergence substation is controlled by a local dispatching automatic voltage control system,

when the control period comes, the method executes the following steps:

step S1, acquiring the voltage regulation demand of a 220kV collection substation high-voltage bus in a jth renewable energy station collection area in a provincial regulation automatic voltage control system, wherein j is a natural number, and j is more than or equal to 1 and less than or equal to the total number of the renewable energy station collection areas in a preset area;

step S2, calculating the total voltage regulation capacity of all 220kV renewable energy stations in the jth renewable energy station gathering area;

step S3, evaluating whether the total voltage regulation capability satisfies the voltage regulation demand;

step S4, if the total voltage regulation capacity is enough to regulate the voltage of the 220kV collection substation high-voltage bus in the jth renewable energy station collection area, the voltage regulation capacity of the 220kV renewable energy station is used for regulating the voltage of the 220kV collection substation high-voltage bus in the jth renewable energy station collection area;

step S5, if the total voltage regulation capacity is not enough to regulate the voltage of a high-voltage bus of a 220kV collection substation in a collection area of a jth renewable energy station, calculating a provincial and local coordination gateway reactive power demand limit range corresponding to the 220kV collection substation;

step S6, the provincial dispatching automatic voltage control system issues the limit value range to a local dispatching automatic voltage control system, the local dispatching automatic voltage control system controls reactive equipment in a 220kV convergence substation in a jth renewable energy station convergence region, so that the reactive equipment supplements and adjusts the voltage of the 220kV convergence substation high-voltage bus in the jth renewable energy station convergence region except that the total voltage adjusting capacity in the step S2 is used for adjusting the voltage of the 220kV convergence substation high-voltage bus in the jth renewable energy station convergence region;

in step S7, j is changed to j +1, and the process returns to step S1.

2. The method for provincial and local coordination control of 220kV collection substation high voltage bus voltages according to claim 1, wherein step S1 comprises:

in a provincial dispatching automatic voltage control system, acquiring the voltage regulation demand of a 220kV collection substation high-voltage bus in a collection area of a jth renewable energy station in a power grid, namely:

wherein:for the control target value of the high-voltage bus of the 220kV collection substation given by global optimization calculation in the provincial automatic voltage control system,is the actual value of the bus voltage,the demand is regulated for the bus voltage.

3. The method for provincial and local coordination control of 220kV collection substation high voltage bus voltages according to claim 2, wherein step S2 comprises:

step S21, receiving the increasable reactive power and the reducible reactive power sent by the ith 220kV renewable energy station in the jth renewable energy station convergence area in real time, and calculating the voltage increase and decrease adjusting capability of the ith 220kV renewable energy station to the 220kV convergence substation high-voltage bus according to the reactive voltage sensitivity of the ith 220kV renewable energy station to the 220kV convergence substation high-voltage bus:

whereinThe increasable reactive power and the decreasable reactive power are uploaded to the ith 220kV renewable energy station in the jth renewable energy station gathering area in real time,the reactive injection voltage sensitivity of a high-voltage bus of a 220kV collection substation in a jth renewable energy station collection area is represented, i is a natural number, and i is more than or equal to 1 and less than or equal to the total number of 220kV renewable energy stations in the jth renewable energy station collection area;

step S22, return to step S21 with i equal to i + 1;

step S23, accumulating the voltage increase and decrease adjustment capacities of all 220kV renewable energy stations in the jth renewable energy station gathering area:

4. the method for provincial and local coordination control of 220kV collection substation high voltage bus voltages according to claim 3, wherein step S3 comprises:

step S31, ifThen checking and judging:

if equation (4) is true, it is determined that the total voltage increase regulation capability of all 220kV renewable energy stations in the jth renewable energy station concentration area is insufficient, wherein,taking 0.5-1.0kV as a threshold value for regulating the voltage of a high-voltage bus of the current coordinated substation; r_pTaking 0.5-0.7 of a threshold value for the coordinated control of the renewable energy source station and the transformer substation;

step S32, ifThen checking and judging:

if equation (5) holds, it is determined that the total voltage reduction regulation capability of all 220kV renewable energy stations in the jth renewable energy station concentration area is insufficient, wherein,taking 0.5-1.0kV as a threshold value for regulating the voltage of a high-voltage bus of the current coordinated substation; r_pAnd taking 0.5-0.7 as a renewable energy source station and a transformer substation coordination control threshold value.

5. The method for provincial and local coordination control of 220kV collection substation high voltage bus voltages according to claim 4, wherein step S5 comprises:

step S51, initializing a reactive power demand limit range of a provincial and local coordination gateway corresponding to the 220kV convergence substation as follows:

wherein:to coordinate the current reactive value of the gateway conservatively,taking 20-30Mvar for provincial and local coordination gateway reactive power regulation dead zone parameter values;

step S52, ifAnd if it is determined in step S31 that the total voltage increase regulation capability of all 220kV renewable energy stations in the jth renewable energy station convergence area is insufficient, calculating the reactive coordination of the 220kV convergence substationThe control regulation requirements are as follows:

according to the calculation result, adjusting the coordination reactive upper limit of a provincial and local coordination gateway corresponding to the 220kV convergence substation to be:

wherein,for the reactive power increase and regulation capacity of the provincial and local coordination gateway corresponding to the 220kV convergence substation sent by the local dispatching automatic voltage control system, the reactive power requirement limit value of the provincial and local coordination gateway corresponding to the 220kV convergence substation is updated as follows:

step S53, ifAnd in step S32, if it is determined that the total voltage reduction regulation capability of all 220kV renewable energy stations in the jth renewable energy station convergence area is insufficient, calculating the reactive power coordination control regulation requirement of the 220kV convergence substation as follows:

whereinThe reactive injection voltage sensitivity of a high-voltage bus of a 220kV collection substation in the electric collection area of the jth renewable energy station is obtained; according to the calculation result, adjusting the coordination reactive upper limit of a provincial and local coordination gateway corresponding to the 220kV convergence substationComprises the following steps:

wherein,for the reactive power reduction regulation capacity of the provincial and local coordination gateway corresponding to the 220kV convergence substation sent by the local dispatching automatic voltage control system, the reactive power requirement limit value of the provincial and local coordination gateway corresponding to the 220kV convergence substation is updated to be:

the corrected limit value range is adjusted by the provincial dispatching automatic voltage control systemAnd sending the voltage to a local dispatching automatic voltage control system, wherein the local dispatching automatic voltage control system collects reactive equipment in a transformer substation by controlling 220kV, so that the voltage regulation capacity of the reactive equipment and the total voltage regulation capacity in the step S2 meet the voltage regulation demand.

6. The method for provincial-local coordination control of 220kV collection substation high-voltage bus voltages according to claim 1, wherein the renewable energy station is a wind power station or a photovoltaic power station.

7. The method for provincial-local coordination control of the voltage of the high-voltage bus of the 220kV collection substation according to claim 1, wherein every 5 minutes is a control period.