The Technical Level and Characteristics of Chinese Switching Power Supply Products in 2024
Article Source:mbd | Author:Sihan Industrial Research Institute | Issuing Time:2024.04.18
1. The technical level of the industry
At present, China has become an important production base in the switching power supply industry, and Chinese power supply enterprises have achieved rapid development, forming a relatively complete industrial chain, including a group of enterprises with certain competitiveness in the switching power supply field. In the field of power adapters, the technology of Chinese domestic enterprises has reached the international advanced level; In the field of server power supply, the overall technological gap between domestic power companies in China and international power giants is gradually narrowing.
2. Technical characteristics of the industry
The technical platforms of switching power supplies mainly include flyback, phase-shifting full bridge, LLC (resonant), ACF (active clamp), PFC (power factor correction), DSP (digital signal processing), etc. Zero voltage/zero current soft switching technology, synchronous rectification technology, all digital control technology and other technologies are widely used in the industry.
① Zero voltage/zero current soft switching technology
The zero voltage/zero current soft switching technology introduces a resonant process before and after the switching process to achieve conduction when the voltage at both ends of the switch is zero, or to turn off when the current flowing through the switch is zero, effectively reducing the switching loss and noise of the circuit, and improving the conversion efficiency.
② Synchronous rectification technology
Synchronous rectification technology uses low conduction resistance power MOSFETs to replace the output rectifier diodes in switching converters, in order to reduce rectification losses and improve efficiency. With the development of computer and communication technology, low-voltage high current switching modules have become one of the important research and development topics in the industry. Synchronous rectification technology has been widely applied in the field of low-voltage high current switching module power supplies.
③ All digital control technology
The control of switch mode power supply has shifted from analog control to mixed analog and digital control, and has entered the stage of full digital control. Using digital signal processors (DSP) or microcontrollers (MCU) as the core, digital power drivers, PWM controllers, PFM controllers, etc
Control objects to achieve power control, management, and monitoring functions. Digital systems in switching power supplies have advantages such as flexibility, easy implementation of modular management, and high integration. The digital control chip and software of the switch converter have been continuously updated and iterated, and its performance can fully meet the current needs of switch power supplies. Therefore, the application of digitization in high-precision power supplies will become increasingly widespread, becoming an important direction for the development of modern power supply technology.
④ Integrated technology for low-power power supply systems
Integrated technology can integrate multiple electronic components into a chip, reducing external discrete components. By using integrated technology, it is convenient to make circuit compensation, temperature compensation, stable driving drift, overload protection, etc. The output voltage is stable, the output current is easy to control, and the efficiency of the switching power source can be improved. Overload and short circuit protection is complete. Fully automated production can be adopted to save manpower, reduce labor costs, and ensure stable product quality, high reliability, and good consistency.
⑤ Power factor correction technology
Due to the input rectification and filtering of switch mode power supplies, distortion of the current waveform in the power grid is caused, containing a large number of harmonic components, resulting in low power factor, pollution to the power grid, and interference with other electrical equipment. Therefore, adding a power factor correction circuit on the input side of the switching power supply corrects the distorted current to a sinusoidal current, which is in the same phase as the voltage, so that the power factor value is close to 1. This is an important technology in designing switching power supplies with input power of over 75W.
⑥ Design Technology for Distributed Power System Architecture
The structure design of distributed power supply system is easy to dissipate heat, can achieve uniform heat distribution, and also helps to modularize AC/DC converter components and N+1 power redundancy, which is conducive to online replacement of failed modules. It is suitable for power supply in workstations composed of ultra high speed integrated circuits (such as image processing stations), digital electronic switching systems, etc.