What are the current electrical technology frontiers
1、 New electrical technology and development of motor and electric appliance
In the second half of the 20th century, the new electrical technology is mainly developing towards new principles, new theories, new materials and new technologies. For example, if the room temperature superconducting material is successfully developed, the resistance loss of the superconducting motor winding will be reduced to zero, which not only solves the problems of armature winding heating and temperature rise, but also greatly improves the efficiency of the motor. More importantly, the critical magnetic field strength and critical current density of superconductor are very high, so that the air gap flux density and winding current density of superconductor motor can be several times or even tens of times higher than that of conventional motor. This greatly improves the power density of the motor and reduces the weight, volume and material consumption of the motor.
In the 21st century, human beings expect to enter a new period of sustainable development. Based on the development of the 20th century, electrical technology will further develop rapidly. In addition to profound changes in the development of traditional electric power, electrical machinery and electrical control, it will also play an important role in promoting the development of energy, transportation and other industries. For example, in terms of energy and electricity, we can use nuclear power, magnetic fluid power, wind power and so on; In terms of transportation, maglev trains and electric vehicles are becoming popular, and MHD propulsion ships are also being studied.
More importantly, the importance of motor is more prominent in machine production and power generation. And the motor has changed from a single motor to a professional motor with different functions. In the field of power generation, such as nuclear power generator, MHD generator, wind power generator, solar power generator, tidal power generator. In the field of motor, such as high-performance permanent magnet motor, AC asynchronous motor, single-phase asynchronous motor, shaded pole motor, hysteresis synchronous motor and so on.
The development of motor not only greatly improves human productivity, but also greatly enriches human life. In our daily life, the motor is everywhere, our air conditioner, our refrigerator, our microwave oven, our computer, more or less have the existence of motor. We can see the importance of motor in our life
2、 Power system
Power system is a system of power generation, transformation, transmission, distribution and consumption. Its function is to convert the natural primary energy into electric energy through power generation power plant (mainly including boiler, steam turbine, generator and auxiliary production system of power plant), and then supply electric energy to each load center through transmission, transformation system and distribution system, and then convert it into power, heat, light and other different forms of energy through various equipment, so as to serve the regional economy and people's life. Because most of the power supply points and load centers are located in different areas, and can not be stored in large quantities, their production, transmission, distribution and consumption are completed at the same time, and form an organic whole in the same area, so the power production must always maintain a balance with consumption. Therefore, the centralized development and decentralized use of electric energy, the continuous supply of electric energy and the random change of load restrict the structure and operation of power system. Therefore, in order to realize its functions, the power system needs to set up corresponding information and control systems in each link and at different levels, so as to measure, regulate, control, protect, communicate and dispatch the process of power production and transportation, so as to ensure that users can obtain safe, economic and high-quality power.
The establishment of a large-scale power system with reasonable structure is not only conducive to the centralized management, unified dispatching and distribution of power production and consumption, reducing the total installed capacity, saving the investment in power facilities, but also conducive to the rational development and utilization of regional energy resources, and meeting the growing power demand of regional national economy to a greater extent. Power system construction is often an important part of national and regional economic development planning.
The emergence of the power system makes the efficient, pollution-free, easy to use, easy to control power widely used, promotes the changes in various fields of social production, creates the era of electric power, and the second technological revolution has taken place. The scale and technical level of power system has become one of the symbols of a country's economic development level.
3、 High voltage and insulation technology
Application technology based on experimental research. This paper mainly studies the performance of various insulating dielectrics and different types of discharge phenomena under the action of high voltage, the insulation structure design of high voltage equipment, the equipment and methods of high voltage test and measurement, the impact of strong electric field, strong magnetic field or electromagnetic wave generated by overvoltage, high voltage or large current of power system on the environment and protective measures, as well as the application of high voltage and large current. High voltage technology has a significant impact on the development of power industry, electrical manufacturing industry and Modern Physics (such as X-ray device, particle accelerator, high-power pulse generator, etc.). High voltage and insulation technology is characterized by strong experimental, theoretical and cross.
Since the late 1960s, high voltage technology has been widely used in fields other than electrical engineering; At the same time, it also adopts new technology to develop itself. The former mainly refers to high-voltage technology in particle accelerator, high-power pulse generator, controlled thermonuclear reaction research, lightning and electrostatic control and protection in aviation and aerospace field, magnetic fluid power generation, laser technology, plasma cutting, underwater oil exploration by electric water hammer, shock processing, stone breaking in human body, as well as electrostatic dust removal, electrostatic spraying Electrostatic copying and other applications. The new technologies used in the field of high voltage include computing the transient process of power system and the wave process of substation by computer; Laser technology is used to measure large current under high voltage; Optical fiber technology is used to transfer and measure high voltage; Using information technology for data processing. All these constitute an important aspect of the development of high voltage technology in recent years.
High voltage power transmission not only can transmit electricity, but also has obvious economy. Local power generation is more resource-saving than transportation power generation, which leads to the current power strategy of high-voltage transportation in China.
4、 Power electronics and electric drive
Power electronics. Power electronic technology is a new technology, which is formed by the intersection of power science, electronics and control theory. It has become an indispensable professional basic course of modern electrical engineering and automation, and plays an important role in the cultivation of professional talents. Electronic technology includes information electronic technology and power electronic technology. Generally speaking, analog electronic technology and digital electronic technology belong to information electronic technology. Power electronic technology is an electronic technology applied in power field. Specifically, it is the technology of using power electronic devices to transform and control electric energy. Power electronics is a subject to study weak current, which is closely related to automation, but it often deals with strong current, so it is called the bridge between weak current and strong current.
Power electronics technology has important applications in motor control, current control, rectification, automation and simulation. Therefore, power electronics has become an important interface between information industry and traditional industry. The application of power electronic technology has penetrated into all aspects of industrial production and social activities.
Electric drive. Electric drive is to use electric motor to convert electric energy into mechanical energy to drive various types of production machinery, traffic vehicles and objects that need to move in life. Since human beings invented and mastered all kinds of machines to help them work, they need to have the motive force to drive them. Apart from human power itself, they initially used animal power, water power and wind power. Later, they invented steam engine, diesel engine and gasoline engine. In the 19th century, they invented electric motor.
The efficiency of the motor is high, the operation is more economical, the transmission and distribution of electric energy is more convenient, and the electric energy is easy to control, so now the electric drive has become the most mechanical transmission mode, and has become an important foundation of industrialization. One way of transmission is mechanical transmission, such as rocker arm, pressure transmission, such as hydraulic transmission, and the way of transmission by controlling motor is electrical transmission. As large as a country, as small as a factory, its electric drive automation technology level directly reflects its modernization level.