【正文】 ，電壓達(dá)到90伏特。術(shù)語(yǔ) 開(kāi)關(guān)模式這個(gè)詞開(kāi)始作為術(shù)語(yǔ)應(yīng)用還是很廣泛的，直到摩托羅拉將其注冊(cè)為商標(biāo)，將這種開(kāi)關(guān)模式的電源市場(chǎng)化，并開(kāi)始強(qiáng)化他們的商標(biāo)。一些潛艇像蘇聯(lián)阿爾法級(jí)潛艇利用兩個(gè)同步發(fā)電機(jī)提供一個(gè)變量三相電流， 2 1500千瓦， 400伏， 400赫茲。2006年，在英特爾開(kāi)發(fā)商論壇，谷歌工程師建議使用一個(gè)單一的12 V電源在PC ，高效率的開(kāi)關(guān)模式用品直接在PCB上。Quasiresonant諧振/開(kāi)關(guān) 一個(gè)諧振/零電壓開(kāi)關(guān)（零電流/零電壓）是一種設(shè)計(jì)的“每個(gè)開(kāi)關(guān)周期提供了一個(gè)量化39。在余下的部分交流周期電容器提供能源的電力供應(yīng)。 反饋電路需求的運(yùn)行功率，然后才可以發(fā)電，從而增加非開(kāi)關(guān)電源。如果有一個(gè)錯(cuò)誤的輸出電壓，反饋電路補(bǔ)償調(diào)整的時(shí)機(jī)與該MOSFET的是接通或關(guān)斷。反饋控制回路是用來(lái)調(diào)節(jié)輸出電壓，通過(guò)改變占空比來(lái)彌補(bǔ)投入的變化電壓。與肖特基二極管相比，它們可將電壓控制在較低范圍。電壓轉(zhuǎn)換器和輸出整流器 如果輸出要與輸入分開(kāi)，常常作為工作電路提供主電源。頻率通常選擇將超過(guò)20千赫，使人們察覺(jué)不到。一個(gè)開(kāi)關(guān)電源設(shè)計(jì)的AC輸入然后變?yōu)橹绷鞴╇姡▽?30V交流變?yōu)?30V直流） ，直流經(jīng)過(guò)整流階段不變。這就是所謂的整流。通常幾個(gè)二級(jí)整流器，一系列電感、電容和濾波提供各種直流輸出低紋波。s however advisable to consult the manual before trying this, though most supplies are quite capable of such operation even though nothing is mentioned in the documentation. However, this type of use may be harmful to the rectifier stage as it will only utilize half of diodes in the rectifier for the full load. This may result in overheating of these ponents, and cause them to fail prematurely.If an input range switch is used, the rectifier stage is usually configured to operate as a voltage doubler when operating on the low voltage (~120 VAC) range and as a straight rectifier when operating on the high voltage (~240 VAC) range. If an input range switch is not used, then a fullwave rectifier is usually used and the downstream inverter stage is simply designed to be flexible enough to accept the wide range of dc voltages that will be produced by the rectifier stage. In higherpower SMPSs, some form of automatic range switching may be used.Inverter stageThe inverter stage converts DC, whether directly from the input or from the rectifier stage described above, to AC by running it through a power oscillator, whose output transformer is very small with few windings at a frequency of tens or hundreds of kilohertz (kHz). The frequency is usually chosen to be above 20 kHz, to make it inaudible to humans. The output voltage is optically coupled to the input and thus very tightly controlled. The switching is implemented as a multistage (to achieve high gain) MOSFET amplifier. MOSFETs are a type of transistor with a low onresistance and a high currenthandling capacity. Since only the last stage has a large duty cycle, previous stages can be implemented by bipolar transistors leading to roughly the same efficiency. The second last stage needs to be of a plementary design, where one transistor charges the last MOSFET and another one discharges the MOSFET. A design using a resistor would run idle most of the time and reduce efficiency. All earlier stages do not weight into efficiency because power decreases by a factor of 10 for every stage (going backwards) and thus the earlier stages are responsible for at most 1% of the efficiency. This section refers to the block marked Chopper in the block diagram.Voltage converter and output rectifierIf the output is required to be isolated from the input, as is usually the case in mains power supplies, the inverted AC is used to drive the primary winding of a highfrequency transformer. This converts the voltage up or down to the required output level on its secondary winding. The output transformer in the block diagram serves this purpose. If a DC output is required, the AC output from the transformer is rectified. For output voltages above ten volts or so, ordinary silicon diodes are monly used. For lower voltages, Schottky diodes are monly used as the rectifier elements。packet39。缺點(diǎn)包括更大的復(fù)雜性，產(chǎn)生高振幅，高頻率能量，必須加低通濾波器，以避免電磁干擾 （ EMI ）之類(lèi)，和紋波電壓的開(kāi)關(guān)頻率和諧波頻率不足。整流器產(chǎn)生穩(wěn)壓直流電壓，然后通過(guò)一個(gè)大型濾波電容器。這可能導(dǎo)致器件過(guò)熱，并導(dǎo)致電源受到損害。 MOSFET的是一種有低導(dǎo)通、高電流能力的晶體管。如果需要輸出直流，糾正變壓器輸出的交流。 簡(jiǎn)單的說(shuō)，非隔離式電源包含一個(gè)電感，而不是變壓器。通過(guò)增加第二個(gè)電感的CUK和SEPIC整流器，或者通過(guò)增加額外的積極開(kāi)關(guān)，各種橋變換器可以實(shí)現(xiàn)。電腦，電視機(jī)和錄像機(jī)用品的開(kāi)關(guān)電源中的光耦合器嚴(yán)格控制輸出電壓。 有幾個(gè)不同的設(shè)計(jì)，變壓器50赫茲與500千赫。諧波可以刪除通過(guò)使用濾波器的過(guò)濾，但非常昂貴，以及電力企業(yè)可能需要一個(gè)非常低的功率因數(shù)，以購(gòu)買(mǎi)和安裝過(guò)濾現(xiàn)場(chǎng)。 “ 效率 較高的輸入電壓在同步整流模式轉(zhuǎn)換過(guò)程中更有效率。 某些應(yīng)用程序，如在汽車(chē)行業(yè)，普通汽車(chē)經(jīng)常使用12伏直流電，在某些工業(yè)環(huán)境中，直流電源選擇，以避免哼聲和干涉和易用性的一體化電容器和電池用來(lái)緩沖的電壓。在國(guó)際空間站使用120伏