Application Analysis of Large Capacity Battery Energy Storage Technology in Wind Power 1 Introduction The power system is a dynamic balancing system, and the power transmission and distribution power must be balanced at all times. Wind energy is an intermittent energy source, and there is a certain error in wind speed prediction. Therefore, wind farms cannot provide continuous and stable power, and power generation stability and continuity are poor. In the traditional power system, the dynamic unbalanced power caused by any small disturbance will lead to oscillation between the units. The large-capacity energy storage system combined with the wind turbine can effectively suppress or mitigate the fluctuation of wind power and reduce the impact of wind power on the power grid. . As long as the energy storage device capacity is large enough and the response speed is fast enough, the complete balance of system power can be realized under any circumstances, which is an idea of ​​actively stabilizing the power system [1]. Since the stabilizing control device associated with the energy storage technology does not have to interact with the excitation system of the generator, it is convenient to use the most effective portion in the system for suppressing the oscillation. At the same time, since the control amount generated by the stable control device can directly act on the source that causes the system to oscillate, and accurately compensate the unbalanced power, the influence of the change of the operating state of the system on the control effect of the control device can be less or even not considered. Therefore, the parameter setting of the device is very easy, and the robustness to the change of the operating state of the system is also very good. 2 battery energy storage technology development status at home and abroad In recent years, developed countries such as Japan, the United States, and Europe have invested heavily in battery energy storage technology and are leading the technology. Japan is at the forefront of research and application of sodium-sulfur batteries, and NGKINSULATORS has received orders for 300MWNAS battery systems and central monitoring systems from the Abu Dhabi Water and Electricity Authority in the United Arab Emirates. In 2009, Panasonic and Matsushita Electric and the Danish power company SEAS-NVE jointly launched an empirical experiment aimed at realizing smart grids. Toshiba announced in 2010 that it will receive an order for Okinawa Electric's "Island Microgrid System Empirical Test" related equipment to be started in Miyako Island in the fall of 2010. It will build a new generation of power system with a renewable energy load with a sharp balance of battery balance power. . Sanyo Electric also introduced 1.5MW·h lithium-ion batteries in its “Western Green Energy Parkâ€, and other manufacturers are actively participating in battery energy storage projects. In Europe and the United States, in 2001, Canada VRBPowerSystems built a 250kW all-vanadium liquid storage battery demonstration system in South Africa to realize the commercial operation of the all-vanadium liquid storage battery. VRB PowerSystems's all-vanadium flow energy storage battery for wind power generation built by HydroTasmaniaon KingIsland in Australia was completed in November 2003. The system has a storage capacity of 800 kW·h and an output of 250 kW. In February 2004, VRBPowerSystems built an all-vanadium flow energy storage battery system with an output of 250 kW and an energy storage capacity of 2 MW·h for CastleValley and UtahPacificCorp. At the end of 2006, the company began to build the largest internationally rated output power of 2MW (pulse output power 3MW) and 12MW·h all vanadium redox flow energy storage battery system for Ireland. In the United States, the two-MW and 6MW all-vanadium liquid flow energy storage battery demonstration operation systems were established by using the technology of Sumitomo Electric Industries Co., Ltd. and VRB Power Systems. Innogy of the UK started construction of the first commercial-scale power storage peaking demonstration power plant in August 2000. It is equipped with a 680MW gas turbine power plant with an energy storage capacity of 120MW·h, which can satisfy 10,000 households. A full day of electricity demand. EVONIK Industries AG announced that it will jointly develop high-capacity, low-cost storage lithium-ion battery power plants for wind and solar power , in conjunction with research and development institutions such as Daimler Automotive, and plan to build a power plant in Saarland in western Germany. 1MW energy storage device. In terms of large-scale battery energy storage device technology, China started late, and there is still a big gap with foreign developed countries. The main performances are as follows: First, the equipment capacity is still small; second, the equipment has short life and low utilization efficiency; It is the level of intelligence of the device is weak. In terms of energy storage applications, China's advanced level from foreign countries is also very large. There are dozens of energy storage power stations in operation abroad, and there is no demonstration project for large-capacity battery energy storage devices in China. At present, the application scale of battery energy storage in China is still very small, but with the adjustment of national energy policy and the implementation of energy conservation and environmental protection policies, its application scale is expected to gradually expand. Shanghai Electric Power Company has built three energy storage demonstration power stations including Tunxi Station, Qianwei Station and Baiyin Station. The power dispatching center can directly implement unified dispatching and remote monitoring of energy storage stations distributed throughout the country through the grid energy storage management system. BYD has established a 1MW (4MW·h) energy storage power station in Longgang, Shenzhen. Xinyuan Holdings Co., Ltd., affiliated to State Grid, and Zhangbei County, Zhangjiakou City, developed and built the nation's first comprehensive project of wind and light energy storage. The total scale of the project is wind power 500MW, photoelectric 100MW and energy storage 70MW. The Zhangbei Fengguang Storage Project is the world's largest trinity demonstration project for wind and light storage, but it has not yet entered the operation. At present, the first phase of the project design has been completed and the first phase of construction work is underway. 3 Rapid development of wind power requirements for energy storage technology As a clean and renewable energy source, wind energy is receiving more and more attention from all countries in the world. China's wind energy reserves are large and widely distributed, and only about 253 million kW of wind energy reserves on land. In recent years, China's grid-connected wind power has developed rapidly. As of the end of 2007, the country's cumulative installed capacity was about 6 million kW. In December 2008, the total installed capacity of wind power in China exceeded 10 million kW, ranking fifth in the world. As of mid-March 2011, the cumulative installed capacity of wind power in China reached 44.5 million kW, and the scale of wind power construction ranked first in the world. This also means that China has entered the ranks of renewable energy powers. The development prospects of China's wind power and other new energy power generation industries are very broad. It is expected that the high-speed development will continue for a long time in the future, and the profitability will also increase steadily as the technology matures. At the same time that China's wind power construction is ranked first in the world, the wind power grid connection problem has always restricted the healthy development of China's wind power. According to statistics, China's wind power installed capacity is connected to 31.07 million kW, but there are still nearly 30% of wind power connected to the grid. This is due to the randomness and intermittent nature of wind energy, resulting in frequent fluctuations in the output of wind turbines, thus contributing to the reliability of wind farms. It is also poor, the proportion of wind power is too large, which will increase the frequency regulation and peaking pressure of the power grid, and the technical requirements and operating costs of the long-distance power transmission of the power grid will increase sharply. Therefore, large-scale grid-connected access to wind farms The operation of the power system also brings some new problems: 1) The randomness and uncontrollability of wind power bring new challenges to power system planning and stable operation; 2) The fluctuation characteristics of wind power and the fluctuation characteristics of grid load are difficult to be consistent, which makes the peak shaving problem of the power grid more prominent, and puts higher requirements on peak shaving capacity and response speed; 3) Due to changes in wind speed, wind turbines are prone to grid voltage and power fluctuations, as well as reactive voltage control and power quality issues. The contradiction between intermittent and volatility of wind power and real-time balance of power system requires that the fluctuation of grid-connected wind power needs to be balanced by conventional power supply regulation and energy storage system, which has become a major problem that has long plagued wind power grid-connected. However, due to geographical limitations, water storage and energy storage power stations do not have universal availability. Therefore, the introduction of universally applicable large-capacity battery energy storage devices combined with wind farms to compensate for the various impacts of wind power fluctuations on the power grid. Is a suitable technology choice [8]. Through the coordination between the energy storage system and the wind power system, not only the impact and impact of wind power on the system are effectively reduced, the consistency of wind power output and prediction is improved, the reliability of power supply is guaranteed, the spare capacity of the power system is reduced, and the power is increased. The economics of the system operation, while improving the ability of the power system to accept wind power. 4 Domestic and foreign requirements for wind power grid connection More and more large and medium-sized wind farms have been built and put into operation. When the proportion of wind power increases gradually, the power fluctuation of wind farms will affect the power quality of local power grids, resulting in voltage fluctuations and flicker. It will have a significant impact on the local power grid, and in severe cases it will cause serious accidents [9,10]. The technical requirements for grid-connected wind farms in various countries have imposed requirements on the active power changes of wind farms, such as: 1) Eltra and Eltra&Elkraft require that the output power of the grid-connected wind farm lmin be less than or equal to 5% of the maximum power of the wind farm. The wind farm can be guaranteed to fall below 20% of the rated power within 2s by the control system. Eltra&Elkraf requires that the power rate per minute of the wind farm be adjustable from 10% to 100%; 2) While E.ON and ESBNG require the wind farm output power to be less than its registered capacity at any time. E.ON requires that the power reduction per minute should be at least 10% of the rated capacity. The power variation of ESBNG required for 15 minutes is related to the scale of the wind farm. The power variation of the wind farm less than 100MW is less than 5% per minute, and the power of the wind farm is less than 200MW per minute. The change is less than 4% of the rated capacity, and the power change per minute of the wind farm greater than 200MW is less than 2% of the rated capacity; 3) Scottish grid connection technology requires that the wind farm output power can exceed the rated power within a reasonable time; 4) China State Grid Corporation has specified the power change rate of wind farms for 1 min and 10 min. The rate of change is related to the installed capacity of wind farms. For example, the maximum change of wind farms of less than 30 MW is 20 MW, and the maximum change of 1 min is 6 MW. 5) Scottish requires the wind farm to start and stop to meet the voltage quality requirements. Scottish also requires the wind farm to start and stop to meet the maximum power change requirements, and no more than 25% of the rated capacity can be jumped off and phased out in 30 minutes. . 5 large-capacity battery energy storage technology for the smooth effect of wind power Obviously, the most important means of adjusting active power is energy storage. High-power, large-capacity energy storage systems can stabilize the volatility and intermittentness of wind power. When the capacity of the energy storage system reaches a certain scale, combining the energy storage system with the wind turbine can effectively suppress or mitigate the fluctuation of wind power and reduce the impact of wind power on the power grid [11, 12]. Large-capacity battery energy storage technology can achieve the following functions in wind power grid connection: 1) Smoothing unit output: Combine the battery energy storage system with the wind turbine, smooth the wind farm output under rapid wind speed disturbance, reduce the impact of wind farm output fluctuation on the grid, and reduce the impact of wind power fluctuation on the grid. 2) Improve the consistency of wind power output and prediction: adjust the output with energy storage as the cooperation, optimize the output according to the output curve predicted by the wind farm, and improve the credibility of wind power output. 3) Improve the dispatching ability: The energy storage system can control the active power and reactive power output of the wind power generation, and is used for power peak shaving, so that the wind power generation unit operates as a dispatch unit, and has the frequency control and fastness to the power system. The ability of auxiliary services such as power response. 4) Peak transfer: The high-power large-capacity energy storage system can collect unstable wind power and release it smoothly at an appropriate time, shifting the peak value and reducing the impact on the power grid; 5) Ensure that the wind power generation system continues to supply power reliably: When the environmental factors or external conditions change rapidly and the wind power generation system cannot output power stably, the energy stored in the energy storage system can generate certain energy and power support functions, ensuring The load is continuously and stably supplied. 6) System operation reliability and redundancy are greatly improved: the parallel group control operation of multiple grid-connected inverters with small capacity enables the system to start different numbers of grid-connected inverters according to the characteristics of various new energy generation systems. The device is controlled so that the power generation efficiency of the system is optimized, and the system reliability and redundancy are further improved. 7) Make wind power generation schedulable: a simple new energy power generation system is greatly affected by environmental factors, so it is impossible to formulate a specific power generation plan. If the energy storage device is configured, the required power can be supplied at a specific time without considering the power generation of the power generation unit at this time. The new energy power generation system can be connected to the power grid to feed the power grid and provide peak clipping. , emergency power support and other services. Simply follow the pre-defined power generation plan to generate electricity. The greater the capacity of the energy storage device, the more free the scheduling of the system, the more economic benefits can be obtained, but the greater the investment required, the key is to find the best economic balance. 6 Conclusion This paper reviews the development status of energy storage technology at home and abroad, analyzes the problems faced by China's wind power development under rapid development, and proposes the application prospect of large-capacity battery energy storage technology in wind power systems. The research results at home and abroad show that the large-capacity battery energy storage technology provides energy storage functions with a wide time range. These provide new ideas and effective solutions to wind power integration, improve the stability of power systems, and improve power quality. Technical Support. Therefore, all countries in the world, especially developed countries, are actively conducting research in this area. We should make full use of China's abundant wind resources and good opportunities for power system reform. We will actively carry out research in this field and provide new technical support for the safe and efficient operation of China's power system. Large-capacity battery energy storage technology plays an increasingly important role in clean energy generation. The market has great potential and has increasingly important economic and social values. Kone Elevator Cable,Control Cable for Elevator,Elevator Travel Cable,Elevator Cable Yuanqi Elevator Parts Co., Ltd. , http://www.cnelevatorparts.com