Research on Micro-miniature Compressed Air Energy Storage System Li Liansheng, Yang Qichao, Zhao Yuanyang (Hefei General Machinery Research Institute National Key in Compressor Technology.
Effect of Compressed Specific Pressure Ratio on Compressor and Expander Efficiency In small compressed air energy storage systems, the effect of changes in compressor and expander efficiency on system efficiency at high pressure ratios needs to be considered. It indicates the influence of compressed air storage pressure on the energy storage efficiency and storage density of the system. That is, the storage energy density of the compressed air energy storage system increases with the increase of storage pressure, but the energy storage efficiency of the system increases with the storage pressure. High and gradually reduced. Therefore, the storage pressure of the compressed air energy storage system needs to be optimized based on factors such as system efficiency, energy storage density and operational reliability.
The output power of the compressed air energy storage system varies with the flow rate at different pressure ratios. As shown, the compressor power consumption and the expander output power of the compressed air energy storage system increase with the increase of the flow rate and pressure ratio. And the power consumption of the compressor increases at an obvious rate. For a fixed capacity compressed air energy storage system, the flow rate of the expander is determined by the power of the expander and the operating pressure. The ratio of compressor flow to expander flow reflects the charge and discharge time of the compressed air energy storage system. When the flow rate is constant, the volume of the gas storage tank determines the length of the peaking time of the compressed air energy storage system. The larger the volume of the gas storage tank, the longer the peaking time of the system.
The maximum efficiency of the system and the minimum tank volume are shown in Table 1. It can be seen from Table 1 that at the same peaking time, as the gas storage pressure increases, the volume of the gas storage tank decreases, but the charging time increases, while the compression power consumption increases, and the energy storage system increases. The efficiency is gradually decreasing. Therefore, the data in Table 1 also indicates that the gas storage pressure of the micro-miniature compressed air energy storage system is closely related to the storage volume, system efficiency and energy storage density.
Table 1 Micro-miniature compressed air energy storage system parameters and performance system peaking gas storage charging gas storage tank volume total pressure total expansion system capacity time pressure time reduction work expansion efficiency 3.2 economic analysis 3 micro-miniature compressed air energy storage system and Its key technology 3.1 system scheme China's wind farm single-machine scale is mainly 2MW, MW units, and the development focus is 5MW. If each 2MW or wind power 3MW unit is equipped with micro-miniature compressed air energy storage system, the principle is as follows. In the micro-miniature compressed air energy storage system, the expander (structure type) and generator specifications can be selected according to the power generation power, and the compressor (structure type) and the gas tank size can be selected according to the gas volume and pressure.
Micro-miniature compressed air energy storage and its utilization principle The peaking time is calculated according to 15, 0 and 60min. In theory, the economic benefits of compressed air energy storage power station mainly include static efficiency and dynamic benefit. The static benefit is the economic and reliability benefits of the power station when it is responsible for peak filling and energy conversion. The dynamic benefit refers to the economic and reliability benefits embodied in the accidental backup power supply, load standby, etc. due to the adaptability, flexibility and high reliability of the energy storage power station. The main functions of the compressed air energy storage system applied to wind power sites are peak capacity and spare capacity, which reduces the installed capacity requirements of wind power, thereby saving investment and operating costs of wind power equipment.
3.3 Key parameters and technical gas storage pressure and its optimization. Compressed air storage pressure is closely related to the energy density of the power generation system and the efficiency of the energy storage system, and needs to be optimized. In order to increase the pressure and reduce the storage volume, it is necessary to select a compressor unit and an expansion unit of different structural types.
Expansion ratio and its control. In the compressed air energy storage system, the expansion process is often in an unstable state, and the change of the inlet parameters has a great influence on the output characteristics of the expander. It is necessary to develop an output performance control technology that meets the requirements of the grid connection technology.
System efficiency and related technologies for improving efficiency. To achieve efficient, reliable and stable operation of energy storage systems under variable operating conditions, it is necessary to improve the efficiency of compressors (groups) and expanders (groups), develop system fluidization machinery optimization and control strategies, and thermal management technologies such as compression. Hot recycling and savings.
4 Conclusions A single wind turbine is equipped with a micro-small compressed air energy storage system, which can effectively improve the quality of wind power generation and photovoltaic power generation, and can be used as an emergency power source, which is easy to operate and maintain, and has the least impact on the failure of such equipment; compressed air The storage pressure is a key parameter of the energy storage system, affecting the system efficiency and the storage density. The choice of storage pressure also needs to consider the cost and operational reliability of the system; the design and manufacture of the expander and the expansion ratio control technology are the key to the development of micro-miniature compressed air energy storage systems.
Aluminium CNC Service,CNC Turning Machine Parts,CNC Milling Stainless Steel,CNC Machining Stainless Steel
Grand Nakamura Mechanical and Electrical (Suzhou) Co., Ltd. , https://www.gns-mp.com