A real-time stability control device suitable for new energy grid-connected systems

Abstract

This invention provides a real-time stability control device suitable for new energy grid-connected systems, relating to the field of new energy grid-connected control. This real-time stability control device for new energy grid-connected systems includes a power grid system, a communication system, a wind power integrated management system, and a wind power inter-regional consumption system. The power grid system includes a main grid, distribution network, wind farms, electrical equipment, and transmission lines. The wind farm includes wind turbines, generator sets, and substations. The communication system consists of a GPS system, a dispatch center, a power dispatch data network, network switches, and a wind power integrated management communication terminal. By combining the wind farm aggregation station with the conditions of wind farms in various regions, inter-regional transmission lines are selectively activated. When a region reaches a low-load period, the electricity generated by the wind farms in that region is transmitted inter-regionally to regions with high load during that period, effectively avoiding excessively high wind curtailment rates and contributing to grid stability.

Description

Technical Field

[0001] This invention relates to the field of new energy grid-connected control systems, specifically a real-time stable control device suitable for new energy grid-connected systems. Background Technology

[0002] The entire system of substations and their transmission and distribution lines at various voltages in a power system is called a power grid. Grid connection, as the name suggests, means merging the power grid together. New energy grid connection mainly includes two forms: wind power and photovoltaic power generation connected to the main grid and distributed power generation connected to the distribution network. my country's abundant wind and solar energy resources are mainly located in the "Three Norths" region. Most new energy power generation is located at the end of the power grid, resulting in a relatively simple power supply structure. The power grid structure is weak and its regulation capacity is limited. Wind power, photovoltaic and other new energy power plants are all connected to the grid and controlled through power electronic converters.

[0003] Taking wind power grid connection as an example, wind power is highly random, intermittent, and fluctuates significantly with irregular frequency. The anti-peak-shaving characteristics of wind power increase the difficulty of grid peak regulation. According to statistics from the Northeast, Inner Mongolia West, and Jilin power grids, the probabilities of wind power anti-peak regulation are 60%, 57%, and 56%, respectively. Due to wind power integration, the peak-valley difference in the Jilin power grid increases for 210 days a year. Due to insufficient peak-shaving capacity, both the Jilin and Inner Mongolia West power grids have experienced wind curtailment during low-load periods. Wind curtailment refers to the phenomenon where, under normal conditions, some wind turbines are shut down due to insufficient local grid capacity, mismatched construction schedules of wind farms, and the inherent instability of wind power. This phenomenon is detrimental to the stable operation of the power grid. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a real-time stability control device suitable for new energy grid-connected systems, which solves the problem of frequent wind curtailment caused by the anti-peak-shaving characteristics of wind power, which affects the stability of the power grid system when new energy is connected to the grid, taking wind power as an example.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a real-time stability control device suitable for new energy grid-connected systems, comprising a power grid system, a communication system, a wind power integrated management system, and a wind power inter-regional consumption system. The power grid system includes a main grid, a distribution network, wind farms, electrical equipment, and transmission lines. The wind farm includes wind turbines, generator sets, and substations. The communication system consists of a GPS system, a dispatch center, a power dispatch data network, a network switch, and a wind power integrated management communication terminal. The wind power integrated management system relies on the wind power integrated management communication terminal for implementation, and the wind power inter-regional consumption system relies on the control of the wind farm collection station for implementation.

[0006] Preferably, the wind power integrated management system comprises a substation integrated automation system, a wind turbine monitoring system, a reactive power compensation system, and a wind farm AGC / AVC control system. The substation integrated automation system is an automated system composed of multiple microcomputers, interface circuits, and communication networks. By collecting various required data and information, and leveraging the high-speed computing power and logical judgment capabilities of computers, it monitors, controls, or adjusts various equipment in the substation. The wind turbine monitoring system is a fully automatic control system capable of controlling the automatic start-up of wind turbines, controlling the mechanical adjustment devices of blade pitch, and stopping the turbines under normal and abnormal conditions. The wind turbine monitoring system is also used to monitor and provide information such as wind turbine operating status, wind speed, and wind direction. The reactive power compensation system improves the proportional constant of active power through reactive power compensation, which helps reduce the losses of power supply transformers and transmission lines, improve power supply efficiency, and improve the power supply environment.

[0007] Preferably, the wind power inter-regional consumption system comprises regional planning, establishment of a regional power load model, and construction of inter-regional transmission lines. The regional planning is based on regional characteristics, the establishment of the regional power load model is based on the current regional characteristics and historical big data on electricity consumption, and the construction of inter-regional transmission lines is based on the principle of complementarity and proximity to analyze and calculate the regional power load model and match the region.

[0008] Preferably, the wind farm AGC / AVC control system comprises wind farm active power control, wind farm reactive power control, an emergency control system, and wind farm power prediction. The wind farm active power control is used to calculate and control the electrical power generated by the wind farm that is converted into other forms of energy (mechanical energy, thermal energy, chemical energy, acoustic energy). The reactive power control is used to calculate and control the reactive power generated by the wind farm (the exchange rate of the electrical energy generated by the wind farm periodically exchanged between the power source and the reactive components). The emergency control system includes an automatic control system and a manual control system. The automatic control system automatically tracks and monitors in real time according to the instructions issued by the dispatch center. When it detects abnormal real-time operating data parameters due to equipment abnormality, it immediately issues an alarm. When it detects a system communication failure or fails to receive instructions from the dispatch center within a timeout period, it immediately switches to the manual control system.

[0009] Preferably, the implementation method of the real-time stability control device suitable for new energy grid-connected systems includes the following steps:

[0010] S1: Establishing a regional joint control objective

[0011] First, the time parameters of each region are unified according to the GPS system to ensure that there is no time deviation. Second, a regional power load model is established based on the regional characteristics and the past regional power consumption. Then, based on the principles of complementarity and proximity, cross-regional wind farm transmission lines are established, that is, wind farms in one region are connected to the distribution network of other regions.

[0012] S2: Establish regional independent control objectives

[0013] (1) The wind turbine monitoring system collects real-time operating data of each wind turbine in the wind farm, and the substation integrated automation system collects real-time operating data of the substation grid connection point;

[0014] (2) Transmit the above data to the communication system and the wind farm AGC / AVC control system;

[0015] (3) The dispatch center sends commands such as the active power target value and active power curve of the wind farm to the wind farm AGC / AVC control system based on the power dispatch data network.

[0016] (4) The wind farm AGC / AVC control system receives commands, performs optimization calculations based on the actual situation of the regional wind farm, determines the target value of active power output of a single wind turbine, and transmits the target value to the wind turbine monitoring system through the wind farm integrated management communication terminal. The wind turbine monitoring system adjusts the corresponding wind turbines according to the target value to achieve real-time stable control.

[0017] S3: Wind farm collection station control

[0018] Wind farm aggregation stations selectively activate inter-regional transmission lines based on the conditions of wind farms in various regions. When a region reaches a low-load period, the electricity generated by the wind farms in that region is transmitted to the high-load area during that period. This can effectively avoid excessive wind curtailment and is conducive to the stability of the power grid.

[0019] This invention provides a real-time stability control device suitable for new energy grid-connected systems. It has the following beneficial effects:

[0020] This invention establishes a connection between independent regional control and joint regional control by setting up a wind power inter-regional consumption system. Independent regional control is mainly achieved through a wind power integrated management system and a communication system. By using GPS to unify time parameters, real-time data from wind farms is collected and analyzed to control the power of wind turbines and substation grid connection points in real time, ensuring the stability of the power grid system. Joint regional control is achieved by establishing a power load model to match and build transmission lines between regions. At the same time, the wind power inter-regional consumption system can rely on wind farm aggregation stations. These stations selectively activate inter-regional transmission lines based on the conditions of wind farms in each region. When a region reaches a low-load period, the electricity generated by the wind farms in that region is transmitted to regions with high load during that period, effectively avoiding excessively high wind curtailment rates and contributing to the stability of the power grid. Attached Figure Description

[0021] Figure 1 This is a system block diagram of the present invention;

[0022] Figure 2 This is a system block diagram of the power grid system of the present invention;

[0023] Figure 3 This is a system block diagram of the wind farm of the present invention;

[0024] Figure 4 This is a block diagram illustrating the control principle of the present invention;

[0025] Figure 5 This is a system block diagram of the communication system of the present invention;

[0026] Figure 6 This is a system block diagram of the wind farm AGC / AVC control system of the present invention;

[0027] Figure 7 This is a logic diagram of the control method of the present invention. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example:

[0030] like Figure 1-6As shown, this embodiment of the invention provides a real-time stability control device suitable for new energy grid-connected systems, including a power grid system, a communication system, a wind power integrated management system, and a wind power inter-regional consumption system. The power grid system includes a main grid, a distribution network, wind farms, electrical equipment, and transmission lines. Wind farms are connected to the main grid after adjustment by substations. The electrical energy transmitted by the main grid is distributed to electrical equipment through the distribution network. Wind farms include wind turbines, generator sets, and substations. Wind turbines convert wind energy into mechanical energy, and generators convert mechanical energy into electrical energy. The communication system consists of a GPS system, a dispatch center, a power dispatch data network, network switches, and a wind power integrated management communication terminal. The dispatch center is generally located near wind farms in various regions, serving as the central control center for wind farms. The power dispatch data network is used to transmit grid automation information, dispatch command instructions, and control information of relay protection and safety automatic devices. The network switches can connect different networks to achieve communication between different networks. The wind power integrated management system relies on the wind power integrated management communication terminal, and the wind power inter-regional consumption system relies on the control of the wind farm aggregation station.

[0031] The wind power integrated management system comprises a substation automation system, a wind turbine monitoring system, a reactive power compensation system, and a wind farm AGC / AVC control system. The substation automation system is an automated system utilizing multiple microcomputers, interface circuits, and communication networks. By collecting various necessary data and information, and leveraging the high-speed computing power and logical judgment capabilities of computers, it monitors, controls, and adjusts various equipment in the substation. The wind turbine monitoring system is a fully automatic control system capable of controlling the automatic start-up of wind turbines, controlling the mechanical adjustment devices for blade pitch, and shutting down turbines under normal and abnormal conditions. The system also monitors and provides information such as wind turbine operating status, wind speed, and wind direction. The reactive power compensation system increases the proportion constant of active power through reactive power compensation, which helps reduce losses in power supply transformers and transmission lines, improves power supply efficiency, and enhances the power supply environment.

[0032] The wind power inter-regional consumption system consists of regional planning, the establishment of regional power load models, and the construction of inter-regional transmission lines. Regional planning is based on regional characteristics, and the establishment of regional power load models is based on current regional characteristics and historical big data on electricity consumption. The construction of inter-regional transmission lines is based on the principles of complementarity and proximity, and the regional power load models are analyzed and calculated to match the regions.

[0033] The wind farm AGC / AVC control system comprises active power control, reactive power control, emergency control, and power prediction. Active power control calculates and controls the electrical power generated by the wind farm, converting it into other forms of energy (mechanical, thermal, chemical, and acoustic). Reactive power control calculates and controls the reactive power generated by the wind farm (the exchange rate of electrical energy periodically exchanged between power sources and reactive components). The emergency control system includes automatic and manual control. The automatic control system automatically tracks and monitors data in real time based on instructions from the dispatch center. It immediately issues an alarm when abnormal real-time operating data parameters are detected due to equipment malfunctions. It switches to manual control immediately when a system communication failure is detected or instructions from the dispatch center are not received within a timeout period. Power prediction requires reasonable forecasting of the regional power load based on changes in regional climate conditions and the construction of a prediction model.

[0034] A method for implementing a real-time stability control device suitable for new energy grid-connected systems includes the following steps:

[0035] S1: Establishing a regional joint control objective

[0036] First, the time parameters of each region are unified according to the GPS system to ensure that there is no time deviation. Second, a regional power load model is established based on the regional characteristics and the past regional power consumption. Then, based on the principles of complementarity and proximity, cross-regional wind farm transmission lines are established, that is, wind farms in one region are connected to the distribution network of other regions.

[0037] S2: Establish regional independent control objectives

[0038] (1) The wind turbine monitoring system collects real-time operating data of each wind turbine in the wind farm, including information such as output active power, reactive power, voltage, and current. The substation integrated automation system collects real-time operating data of the substation grid connection point, including information such as voltage, current, active power, reactive power, active power power factor, etc. of the substation grid connection point.

[0039] (2) Transmit the above data to the communication system and the wind farm AGC / AVC control system;

[0040] (3) The dispatch center sends commands such as the active power target value and active power curve of the wind farm to the wind farm AGC / AVC control system based on the power dispatch data network.

[0041] (4) The wind farm AGC / AVC control system receives commands, performs optimization calculations based on the actual situation of the regional wind farm, determines the target value of active power output of a single wind turbine, and transmits the target value to the wind turbine monitoring system through the wind farm integrated management communication terminal. The wind turbine monitoring system adjusts the corresponding wind turbines according to the target value to achieve real-time stable control.

[0042] S3: Wind farm collection station control

[0043] Wind farm aggregation stations selectively activate inter-regional transmission lines based on the conditions of wind farms in various regions. When a region reaches a low-load period, the electricity generated by the wind farms in that region is transmitted to the high-load area during that period. This can effectively avoid excessive wind curtailment and is conducive to the stability of the power grid.

[0044] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A real-time stability control device suitable for a new energy grid-connected system, comprising a grid system, a communication system, a wind power comprehensive management system and a wind power cross-region consumption system, characterized in that, The power grid system comprises a main grid, a distribution grid, a wind farm, a power consumption device and a transmission line, the communication system is composed of a GPS system, a dispatching center, a power dispatching data network, a network switch and a wind power integrated management communication terminal, the wind power integrated management system is realized by relying on the wind power integrated management communication terminal, and the wind power cross-region consumption system is realized by relying on wind farm collection station control; The wind power cross-region consumption system is composed of regional planning, regional power load model establishment and cross-region transmission line, the regional planning is carried out according to regional characteristics, the regional power load model is established according to current regional characteristics and past big data power consumption, and the cross-region transmission line is built based on the analysis and calculation of the regional power load model according to the complementary principle and the nearby principle. The wind power integrated management system is composed of a booster station integrated system, a wind turbine monitoring system, a reactive power compensation system and a wind farm AGC / AVC control system, the wind farm AGC / AVC control system is composed of wind farm active power control, wind farm reactive power control, an emergency control system and wind farm power prediction, the wind farm active power control is used to calculate and control the electric power generated by the wind farm into other forms of energy, the reactive power control is used to calculate and control the reactive power generated by the wind farm, the emergency control system comprises an automatic control system and a manual control system, the automatic control system automatically tracks and monitors in real time according to the instructions issued by the dispatching center, and immediately alarms when detecting that the real-time operation data parameters are abnormal due to equipment abnormalities, and immediately switches to the manual control system when detecting that the system communication fails or the dispatching center instructions are not received within a timeout period. 2.The real-time stability control device for grid-connected system of new energy according to claim 1, wherein, The booster station integrated system is an automatic system composed of multiple microcomputers, interface circuits and communication networks, which realizes the monitoring, control or adjustment of various devices in the substation by collecting various required data and information and using the high-speed computing power and logical judgment ability of the computer, the wind turbine monitoring system is a full-automatic control system capable of controlling the automatic start of the wind turbine, controlling the mechanical adjusting device of the blade pitch and stopping under normal and abnormal conditions, the wind turbine monitoring system is also used for monitoring to provide wind turbine operation state, wind speed and wind direction information, and the reactive power compensation system improves the proportion constant of active power by reactive power compensation, which is beneficial to reducing the loss of power supply transformer and transmission line, improving power supply efficiency and improving power supply environment. 3.The implementation method of the real-time stability control device suitable for the grid-connected system of new energy according to claim 1, characterized in that, The method comprises the following steps: S1: establishing a regional joint control target First, unify the time parameters of all regions according to the GPS system to ensure that there is no deviation in time, second, establish a regional power load model according to regional characteristics and past regional power consumption, and third, establish a cross-region wind farm transmission line according to the complementary principle and the nearby principle, that is, integrate the wind farm of one region into the distribution grid of other regions; S2: establishing a regional independent control target (1) Using the wind turbine monitoring system to collect real-time operation data of each wind turbine in the wind farm, and using the booster station integrated system to collect real-time operation data of the grid-connected point of the booster station; (2) The above data is transmitted to the communication system and the wind farm AGC / AVC control system; (3) The dispatching center issues the wind farm active power target value and active power curve command to the wind farm AGC / AVC control system according to the power dispatching data network; (4) The wind farm AGC / AVC control system receives the command, optimizes the calculation combined with the actual situation of the regional wind farm, determines the active power output target value of a single wind turbine, and transmits the target value to the wind turbine monitoring system through the wind farm integrated management communication terminal. The wind turbine monitoring system regulates the corresponding wind turbine according to the target value to realize real-time stable control; S3: Wind farm collection station control The wind farm collection station selects the cross-region transmission line according to the situation of each regional wind farm, and selectively opens the cross-region transmission line. When a certain region reaches the low load period, the power generated by the wind farm in this region is transmitted to the high load period, effectively avoiding the high probability of wind power abandonment, and is conducive to the stability of the power grid.

Images