Talking about the rectifier circuit in power electronic technology

Since the advent of the first thyristor in the 1950s, power electronics technology has begun to enter the stage of modern electrical drive technology. The silicon-controlled rectifier device developed on this basis is a revolution in the field of electrical drive and transforms electrical energy. And control has entered the era of converters composed of power electronic devices from rotating converter units and static ion converters, which marked the birth of power electronics. In the 1970s, thyristors began to form a series of products ranging from low voltage and small current to high voltage and large current. The semi-controlled devices that ordinary thyristors cannot self-shut down are called the first generation of power electronic devices. With the continuous improvement of power electronic technology theoretical research and manufacturing technology level, power electronic devices have been greatly developed in terms of ease and type, which is another leap in power electronic technology. GTR.GTO, power MOSFET, etc. have been developed successively. Turn off the fully controlled second-generation power electronic devices. The third-generation power electronic devices represented by insulated gate bipolar transistors (IGBTs) have begun to develop in the direction of easy, high frequency, fast response, and low loss. In the 1990s, power electronic devices are developing in the direction of integration, standard modularization, intelligence, and power integration. Based on this, a theoretical research, device development, and application penetration of power electronic technology has been formed. Shanghai power electronics technology is the most competitive high-tech field.  The rectifier tube is the simplest and most widely used device among power electronic devices. At present, three series of products of ordinary type, fast recovery type and Schottky type have been formed. Power rectifiers play a very important role in improving the performance of various power electronic circuits, reducing circuit losses and improving current efficiency. Since 1958, when General Electric Company of the United States developed the first industrial common thyristor, its structure improvement and process reform laid the foundation for the development and research of new devices. In the following ten years, the two-way, inverter and inverse thyristor were developed and developed. Conductive and asymmetrical thyristors, so far, the thyristor series products still have a wider market.  In 1964, the first successful trial production of 0.5kV/0.01kA shut-off GTO in the United States has been achieved so far, and the current turn-off GTO has reached 9kV/0.25kA/0.8kHz, and currently it has reached 9kV/2.5kA/ At 0.8kHZ and 6kV/6kA/1kHZ levels, GTO has the largest capacity among various self-shut-off devices, but its operating frequency is the lowest, but it has obvious advantages in high-power electric traction drives, so it is in medium voltage , Occupies a place in the field of large passenger volume. The GTR series products were developed in the 1970s, and their rated values have reached 1.8kV/0.8kA/2kHZ, 0.6kV/0.003kA/100kHZ. It has the characteristics of flexible and mature circuit composition, low switching loss and short switching time. 2. It is widely used in medium frequency circuits. As a high-performance, large-capacity third-generation insulated gate bipolar transistor IGBT, it has voltage control, large input impedance, low drive power, low switching loss and operating frequency. High-level characteristics, it has broad prospects for development. IGCT is a new type of device developed recently. It is a device developed on the basis of GTO. It is called an integrated gate commutated thyristor. It is also called an emitter turn-off thyristor. Its instantaneous switching frequency can reach 20kHZ. Breaking time is 1μs, dildt 4kA/ms, du/dt10-20kV/ms, AC blocking voltage 6kV, DC blocking voltage 3.9kV, switching time <2ks, when the conduction voltage drop is 3600A, 2.8V, switching frequency> 1000Hz.  Entering the research and development of power electronic devices in the 1990s, it has entered the era of high frequency, standard modularization, integration and intelligence. From theoretical analysis and experiments, it is proved that the reduction of the volume and weight of electrical products is inversely proportional to the square root of the power supply frequency. In other words, when we greatly increase the standard second frequency of 50Hz, the volume and weight of electrical equipment using such power frequency It can be greatly reduced, making electrical equipment manufacturing save materials, saving electricity more obviously during operation, and greatly improving the system performance of the equipment, especially for the aerospace industry, which is of far-reaching significance. Therefore, the high frequency of power electronic devices is the leading direction of power electronic technology innovation in the future, and the standard module of the hardware structure is the inevitable trend of device development. The current advanced modules include switching elements and freewheeling diodes in reverse parallel with them. Multiple units of internal and drive protection circuit are standardized and produced serial products, and can reach a very high level of consistency and reliability. At present, many large companies in the world have developed IPM intelligent power modules. For example, Japan's Mitsubishi, Toshiba and the United States' International Rectifier Company have already launched mature products. The main features of the IPM intelligent power module of Shindenmoto Company in Japan are: 1 It integrates power chip, detection circuit and driving circuit inside, making the structure of the main circuit the simplest. 2 Its power chip adopts IGBT with high switching speed and small drive current, and has its own current sensor, which can efficiently detect over-current and short-circuit current, so as to protect the power chip safely.  3 In the internal wiring, the wiring length of the power supply circuit and the drive circuit is controlled to the shortest, so as to well solve the problems of surge voltage and noise affecting misoperation.  4 Comes with reliable safety protection measures, when a fault occurs, it can turn off the power devices in time and issue a clear instruction from Prime Minister Zhu Ji in 1998. In the future, the construction of the national innovation system must be accelerated. Therefore, it can be said with certainty that in the early 21st century In the development of the country, technological innovation will become the dominant content of the work of enterprises, and the development and establishment of a technological innovation mechanism suitable for China's national conditions in the electrical industry will promote the continuous upgrade and progress of the new electrical industry through the rapid progress of power electronic technology and then go global. Although power electronics technology has many common characteristics of microelectronics technology, such as rapid development and changes, its penetration and innovation performance is very prominent, its vitality is exceptionally strong, and it is in the sunshine industry status, and it merges with other disciplines and creates new opportunities for development. , And power electronics technology has its own unique characteristics, such as high voltage, large capacity and large control power range. Therefore, the difficulty of technological innovation lies in the need to cross the barrier of high voltage and high power, and the comprehensive difficulty of the technology. , Such as the material industry and manufacturing process, and the reliability of power electronic devices is an extremely important technical indicator. For this reason, the innovation of power electronics technology is interpenetrating with a variety of disciplines and has a strong penetration in various industrial fields. Therefore, the power electronic technology is closely related to the country's basic industries, and the requirements for matching with national development guidelines and industrial policies will become stronger and stronger in the 21st century. Power electronics technology is also called energy flow technology, so the development and innovation of power electronics technology is an important part of the sustainable development strategy program in the 21st century. Accelerating the transformation of modern power electronics in the early 21st century will surely form a sunrise high-tech industrial chain and promote technological innovation in my country's industrial field.  The innovation of power electronic technology and the manufacturing process of power electronic devices have become the most competitive position in the field of industrial automation control and mechatronics in all countries in the world. All developed countries have injected great manpower, material and financial resources in this field to make In terms of the theoretical research on power electronics technology, Japan, the United States, France, the Netherlands, Denmark and other Western European countries can be said to go hand in hand. In these countries, various advanced power electronics power quantities are continuously developed and improved to promote electric power Electronic technology is moving towards high frequency, realizing high efficiency and energy saving of electrical equipment, laying an important technical foundation for realizing the miniaturization, light weight, and intelligence of industrial control equipment, and it also depicts the continuous expansion and innovation of power electronic technology in the 21st century. Broad prospects. Compared with foreign developed countries, my country’s comprehensive technical capabilities for developing power electronic devices still lag far behind. To develop and innovate my country’s power electronics technology and form an industrial scale, it is necessary to take the lead in industry-university innovation with Chinese characteristics. The way is to firmly adhere to and master the method of combining production, learning, and research to take the road of common development. From tracking foreign advanced technology, gradually embarking on independent innovation, innovation from interdisciplinary mutual penetration, innovation from device development selection and circuit structure transformation, this is especially practical for power technology innovation. It is also necessary to guide innovation from the device manufacturing process technology, and to innovate from the application of new material science, so as to promote the technological innovation of the power electronics manufacturing process and improve the reliability of the device. As a result, a basic accumulation-based innovation path is formed. And it is necessary to organically integrate technological innovation with product application and market promotion, which has accelerated the self-reinforcing cycle of technological innovation, and has a stable foundation for promoting and driving technological innovation, so that my country's power electronic technology and device manufacturing process technology can have a considerable development , And form a brand-new waste-to-sun industry, transform it into huge productivity, promote my country's industrial field from a rough management to a centralized one, and promote the national economy to develop at a high speed, height and sustainability.