From the mid-1980s to the end of the 20th century, great progress has been made in the research, development, production, application and introduction of foreign technology and power supply products in China.
Since the late 1980s, high-frequency pulse width modulation (PWM) technology has been successfully and widely used in rectifier products. After 1990, high-frequency switching rectifiers have gradually replaced the thyristor phase-controlled rectifiers that have been used for many years. Compared with phase-controlled rectifiers, high-frequency switching rectifiers have undeniable advantages in terms of technical indicators, economic indicators and application effects. Since high-frequency switching power supply has a huge market in my country, since 1990, there have been dozens of high-frequency switching power supply manufacturers with certain research and development capabilities and production scale in my country.
The late 1990s was a period when my country's communication power supply entered a period of upgrading. By the end of 1994, whether it was the renewal of the original communication station power supply or the selection of the newly built communication station power supply, the high-frequency switching power supply was unanimously preferred. my country's communication industry has been using thyristor phase-controlled power supplies for 20 zu 30 years and has gradually withdrawn from the market of communication power supplies. The output voltage specifications of the high-frequency switching rectifiers independently developed and produced in my country are -24V and -48V, and the single-unit current is 10~100A. The output current of the power system composed of high-frequency switching rectifier modules can reach thousands of amperes. The main electrical technical indicators of high-frequency switching rectifiers produced by some manufacturers, such as voltage regulation accuracy, input power factor and efficiency, have reached or exceeded the technical level of similar foreign products, and the efficiency of PWM hard-switching rectifiers can reach 90% 92% , The efficiency of the soft-switching working mode can reach 94%~95%.