【正文】 源的發(fā)展過程可以了解國際開關電源發(fā)展的一個側面，雖然一般說來，我國技術發(fā)展水平與國際先進水平平均有5～ 10 年差距。特點是：多路輸出，不 可維修性，要求長期不改變性能，設置冗余模塊，可靠性高， EMC 滿足空間環(huán)境條件，高效，輕小。要求電源沖擊電流小，動態(tài)特性好，無過沖，負載個影響軟開關性質。 90 年代，中小型（ 500W 以下） AC－ DC 和 DCDC 開關電源的特點是：高頻化（開關頻率達 300－ 400kHZ）以達到高功率密度，體小量輕；力求高效和高可靠；低成本；低輸出電壓（ ≤3V； AC 輸入端高功率同數(shù)等。開關電源高頻化可以縮小體積重量，但開關損耗卻更大了（功耗與頻率成正比）。 由于輸入端有整流一電容元件， AC－ DC 開關電源及一大類整流電源供電的電子設備（如逆變器， UPS）等的電網測功率團數(shù)僅為， 80 年代用 APFC 技術后可提高到 ～ ，既治理了電網的諧波 “污染 ”，又提高了開關電源的整體效率。 以上簡要回顧了開關電源發(fā)展的歷程和取得的業(yè)績。 90 年代末又提出了新型開關電源的研制開發(fā)，這也是新世紀開關電源的發(fā)展遠景。如電流型控制及多環(huán)控制，電 荷控制，一周期控制，功率因數(shù)控制， DSP 控制；及相應專用集成控制芯片的研制成功等，使開關電源動態(tài)性能有很大提高，電路也大幅度簡化。 關技術使高效率高頻開關變換器的實現(xiàn)有了可能。 可以看出 20 一 30 年中，我國開關電源的應用領域和技術性能有很大進展，這與因家基礎工業(yè)和國力增強有密切關系，也和國際先進開關電源技術影響有關。輸出 20kW， 500A，開關頻率 40kHZ，效率 92％。 90 年代我國又研制開發(fā)了一批新型專用非關電源，典型例子如下： 。因此對開關電源提出了小型輕量要求，包括磁性元件和電容的體積重量要小。 to efficient and reliable。 spacecraft, submarines, military power and switch the batteries used portable electronic devices (such as mobile puters, mobile phones, etc.) need more small , Lightweight power. Hence the switch to power a small light requirements, including magic ponents and capacitors the size of small weight. In addition switching power supply requirements to higher efficiency, better performance, reliability, and so on. China39。s level of technological development with the international advanced level in an average of 5 to 10 gap. 1970s, I join in black and white TV sets, small and mediumsized puter in the beginning of 5 V ,20200A, 20kHZ ACDC switching power supply. 1980s into mass production and extensive application stage and Development of ~ 5 MHz quasiresonant softswitching power supply. In the 1980s, China39。 ZVTPWM/ZCTPWM (90 in the early) fullbridge phaseshift ZVZCSPWM (90 years), and so on. China has The latest softswitching technology to 6 Kw power of munication, efficiency up to 93% 3. Control Technology progress. Such as the current control and multiloop control, load control, a cycle control, power factor control, DSP control, and the corresponding private Integrated control of the successful development of the chip, so that switching power supply has greatly improved dynamic performance, the circuit also greatly simplified 4. Active Power Mission of Correction ( APFC) the development, improve the ACDC switching power supply power factor. Due to the importation Rectification of a capacitora device, ACDC switching power supply and a large class of the rectifier power supply electronic equipment (such as inverters, UPS), and so the power grid measuring only a few corporations with the APFC ,80 technology can improve To to , both the management of the power grid harmonic pollution and also