Power electronic technology is a kind of current aiming technique that tricks power electronic devices to transform and control electric energy. The basic functions include: rectification, inverter, chopping, frequency conversion, switching, intelligent control, etc.

　　1 Application field of power electronic technology 　　Power electronic technology is a kind of current aiming technique that coaxes power electronic devices to transform and control electric energy. The basic functions include: rectification, inversion, chopping, frequency conversion, switching and intelligent control. It enables the power frequency electric energy of the power grid to be finally converted into electric energy of different nature and different purposes, in order to comply with the different needs of the ever-changing power assembly. Modern power electronic technology is mainly used in the following three areas:

　　1) The frequency converter is a combination of microelectronics, power electronics and I control technology. It converts a fixed frequency AC power source into an adjustable voltage and frequency adjustable AC power to achieve stepless speed regulation of the AC electromechanical system. It plays a prominent role in saving electricity, improving production technology, and raising the level of production automation.

　　2) Electronic power supplies are mainly divided into switching power supplies and uninterrupted power supplies. In addition, there are many other types, such as variable frequency power supplies, electrolytic plating power supplies, welding power supplies, induction heating power supplies, charging power supplies, neon lights and lighting power supplies. There are many types and widespread distribution. Provide power support for modern communications, computing, lighting and other industries.

　　3) The application in the power system includes: a power generation system, static excitation control assembly of large-scale generators, variable speed and constant frequency of hydraulic and wind power generators, variable frequency speed regulation of fans and water pumps in power plants, solar power generation control system: hum Electrical system, flexible AC transmission technology (FACTS), high voltage direct current transmission technology (HVDC), static var compensator (SVC): c power distribution system: d. power consumption system.　　2 Discussion on the growth trend of power critical technologies

　　2.1 Solar power generation technology

　　Solar-type inexhaustible renewable energy, .-J YongJ huge amount. Years of solar radiation energy, depending on the difference of latitude, can reach 870～3400KWh/m20 according to the conversion efficiency 020. In general, a solar cell with an area of 10 square meters can provide 3000-5000KWh/m2 of electricity throughout the year, which is enough for For general households, solar power technology mainly includes photovoltaic power generation (PV) technology and solar thermal power generation technology.

　　Photovoltaic power generation (PV) technology, which uses solar cells to directly convert solar energy into electrical energy, is considered to be one of the most promising technologies for industrial-scale use of renewable energy in the next century. At present, the global photovoltaic power generation scale is still small. The output of a single solar cell increases rapidly in capacity, doubling approximately every 3-4 years. By the middle of the next century, the installation capacity of photovoltaic power generation will be considerable. The key to large-scale use of photovoltaic power generation technology is its price. Due to the progress of photovoltaic cell research in recent years, the price of photovoltaic power generation is expected to compete with conventional power generation technologies around 2000.webcam factory

　　2.2 Fuel cell power generation technology 　　 Fuel cell (FC) type is an assembly that directly converts the chemical energy of fuel into electrical energy. The fuel cell power generation efficiency is high, and the power can reach more than 600/o. If the high temperature fuel cell is combined with the combined cycle, the efficiency can reach 85%. Moreover, the efficiency is greatly affected by the size and load of the fuel cell. Fuel cell power generation can quickly track load changes, with a speed of up to 500/o of full load change per second, and strong peak shaving capabilities.

　　The important advantage of FC power generation is that the pollution of the stack is very small, and because there is no combustion process, it can achieve practically zero emissions. The fuel cell has another advantage-saving water. This is extremely important to our country where water capital is lacking. In addition, fuel cell power generation still has the advantages of being suitable for distributed power supply, saving power transmission investment, modular structure, and easy expansion.

　　2.3 Flexible thanks to L transmission technology

　　Flexible AC Transmission System (FACTS) is a new technology that emerged in the late 1980s and has grown rapidly in recent years. Experts predict that this technology will cause major changes in power transmission and distribution in the future, and will play an important role in enriching the existing power grid capital and realizing the efficient use of electric energy. The so-called "flexible AC power transmission technology" refers to the use of large power electronic devices as large power high-voltage switches, and other power equipment to form FACTS equipment to achieve control of power system parameters, such as line impedance, phase angle, and power control. Continuous conditioning and control, thereby greatly improving the transmission capacity of transmission lines and improving the stability of the power system, reducing transmission consumption.

　　2.4 Electric energy storage technology

　　Electric energy storage is an important way to achieve high-efficiency energy use. In addition to pumped storage, a practical energy storage system is battery energy storage (BESS). Its focal component is an AC-DC converter composed of storage batteries and GTO devices. The battery energy storage system can be used as a spinning reserve, as well as a peak shaving and R local frequency power supply, or directly installed in important users as a large uninterrupted power supply. At the same time, BESS also has the function of reactive power conditioning.

　　2.5 Power quality control technology

　　An important part of the efficient use of electric energy is to provide users with reliable and high-quality electric energy supply. The growth of modern society has put forward higher and higher requirements for improving the reliability of power supply and improving the quality of power. In modern enterprises, due to the adoption of variable frequency speed control drives, robots, automatic production lines, and fine processing tools, due to the increasingly common use of programmable controllers and computer information cave systems, the control of power quality is strict. Requirements. These equipments are very sensitive to power fluctuations and various interferences, and any deterioration in power supply quality may cause a decline in product quality, resulting in heavy losses.

　　3Exhibition of new application fields of modern power electronic technology

　　1) Energy-saving electromechanical systems, design special electromechanical and special power electronic control equipment to improve the efficiency of electric energy: 2) Electric vehicles and charging station network, the use of electric vehicles has become an important issue for environmental protection, and its charging network The construction is still in the preliminary stage, so there will be a lot of room for growth; 3) The medium and high voltage DC transmission and distribution system, which has the advantages of high power factor, low grid pollution, and energy saving; 4) Electric energy storage and assembly, deceive power electronics The technology stores electric energy in batteries or superconducting coils, which can realize the storage of electric energy and provide a solution to the reasonable deception of electric energy that cannot be achieved.