ML Series 12W

AC/DC conversion is to convert AC to DC, the power flow direction can be bidirectional, the power flow from the power supply to the load is called "rectifier", the power flow from the load back to the power supply is called "active inverter". AC/DC converter input is 50/60Hz alternating current, which must be rectified and filtered, so relatively large filter capacitors are essential. At the same time, due to safety standards (such as UL, CCEE, etc.) and EMC directives (such as IEC, FCC, CSA), EMC filtering and components conforming to safety standards must be added to the AC input side, this limits the miniaturization of AC/DC power supply volume. In addition, due to the internal high-frequency, high-voltage and high-current switching actions, it is more difficult to solve the EMC electromagnetic compatibility problem, which also puts forward high requirements for the internal high-density installation circuit design. For the same reason, high-voltage and high-current switching increases the power consumption and limits the modularization process of AC/DC converters, therefore, it is necessary to use the power system optimization design method to make its work efficiency to a certain degree of satisfaction. AC/DC conversion can be divided into half-wave circuit and full-wave circuit according to the wiring mode of the circuit. It can be divided into single-phase, three-phase and multi-phase according to the number of power supply phases. According to the working quadrant of the circuit, it can be divided into one quadrant, two quadrants, three quadrants and four quadrants.

Simple design: only a power module, with a small number of discrete components, you can get the power supply. Shorten the development cycle: the module power supply is generally equipped with a variety of input and output options. Users can also repeat superposition or cross superposition to form a building block combined power supply to achieve multiple inputs and outputs, greatly reducing the prototype development time. Flexible change: If the product design needs to be changed, it only needs to convert or connect another suitable power supply module in parallel. Low technical requirements: modular power supplies are generally equipped with standardized front ends, highly integrated power modules and other components, thus making power supply design simpler. The module power supply shell has a trinity structure of heat sink, radiator and shell, which realizes the conduction cooling mode of the module power supply and makes the temperature value of the power supply close to the minimum value. At the same time, it gives the module power Jinyu its table packaging. High quality and reliable: the module power supply is generally fully automated production, and with high-tech production technology, so the quality is stable and reliable. Wide range of uses: modular power supply can be widely used in various fields of social production and life, such as aerospace, locomotive and ship, military weapons, power generation and distribution, post and telecommunications, metallurgy and mining, automatic control, household appliances, instruments and meters, scientific research and experiment, etc., especially in the field of high reliability and high technology.

The switching power supply module is a modular package of discrete components on the switching power supply, thus forming a smaller and higher power density module power supply, and its internal circuit is also a switching power supply. Switching power supply can be divided into AC/DC and DC/DC two categories, DC/DC converter has been modular, and the design technology and production process at home and abroad have been mature and standardized, and has been recognized by users, but AC/DC modular, because of its own characteristics in the process of modularization, encountered more complex technology and process manufacturing problems.

DC/DC conversion is to convert a fixed DC voltage into a variable DC voltage, also known as DC chopping. Chopper works in two ways, one is the pulse width modulation mode Ts unchanged, change ton (general), the second is the frequency modulation mode, ton unchanged, change Ts (easy to produce interference). Its specific circuit consists of the following categories: (1) Buck circuit-step-down chopper, its output average voltage Uo is less than the input voltage Ui, the polarity is the same. (2) Boost circuit-boost chopper, its output average voltage Uo is greater than the input voltage Ui, the polarity is the same. (3) Buck-Boost circuit-buck or boost chopper, its output average voltage Uo is greater than or less than the input voltage Ui, polarity is opposite, inductive transmission. (4) Cuk circuit-buck or boost chopper, its output average voltage Uo is greater than or less than the input voltage UI, polarity is opposite, capacitive transmission. Today's soft switching technology has made a qualitative leap in DC/DC. A variety of ECI soft switching DC/DC converters designed and manufactured by VICOR Company in the United States have maximum output powers of 300W, 600W, 800W, etc. The corresponding power density is (6, 2, 10, 17)W/cm3, and the efficiency is (80-90)%. The latest RM series of high-frequency switching power supply modules using soft switching technology introduced by NemicLambda Corporation of Japan has a switching frequency of (200~300)kHz and a power density of 27W/cm3. Synchronous rectifiers (MOS-FET instead of Schottky diodes) are used to increase the efficiency of the entire circuit to 90%.