EMC電(dian)磁兼(jian)容(rong)原(yuan)理(li)

EMC - a definition
EMC means nothing more than "an electronic or electrical product shall work as intended in its environment. The electronic or electrical product shall not generate electromagnetic disturbances, which may influence other products". In other words, EMC deals with problems of noise emission as well as noise immunity of electronic and electrical products and systems. Electromagnetic disturbances occur as conducted interference as well as radiated emissions and immunity problems.
Generally EMC, Electro Magnetic Compatibility, should really not be difficult to understand, but as you know, the devil is in the details. Let us explain the topic in a little bit more details. For those of you who are EMC-experts, we hope you excuse us for making some "non-scientific" simplifications. 
The word EMC does not include the influence of electromagnetic waves (either desired or undesired) on biological systems. This is a much larger field and is covered by the expression "EMCE" ("E" is for environmental), which is not the topic here and is also not the field in which EM TEST works.

Where EMC got started
The history of EMC
Let us go back in the history of EMC. EMC is older than you may believe.
We are all living with our history. The same is for EMC. You may not know, as many EMC experts also do not know, how everything was started. We want to give you a short summary of the history of EMC in Europe. The following is not given in great detail, but it does illustrate why we are where we are today in the EMC world.

The new age of communication in Europe began 1892 when the German Parliament voted to create the "Law of egraph in the German Empire". This was the first law in the world that dealt with influences of electromagnetic disturbances on products and installations in the field of egraph technique. This law also regulated the procedures to be followed in case such electromagnetic disturbances were found. People at that time had discovered very quickly that cables did disturb each other. The disturbances on egraph and ephone communication were the most severe. The German Society of Electrotechnicians, founded in 1893, was the foundation of what today is well known as VDE. Wilhelm von Siemens was one of the original founders of this famous society.

More than 110 years ago EMC was not a big matter but this was changed immediay in the evening of December 22 in 1920. On this night, the radio station of König Wusterhausen southeast of Berlin broadcasted the Christmas concert of the German mail officials. The concert was a live event and the audience included the German Chancellor Hermann Müller, who was close to the concert location in the famous castle of König Wusterhausen. The Chancellor was not very amused by the electrical noise interference generated by vehicles passing by and he gave strict orders to immediay prevent such disturbances. The hour of "Radiated Emission" had come and was then later on called EMC.

EMC standardization in the past
The first steps towards standardization ...
Germany was among the first to recognize the need to prevent and solve the problems of radiated emissions. In 1933, the international committee for radiated emissions, better known as CISPR was founded. Late in the 60's, concrete investigations were made to deal with the immunity of electrical products. In 1973 the International Electrotechnical Commission, the IEC, founded the technical committee TC77 whose function is to develop standards related to EMC.

In the 2nd World War knowledge of electromagnetic waves and their ability to create disturbances was used. During the war, radar technology was developed. Not only did the new communication technologies of radio, evision and ephone require electromagnetic compatibility, they were the driving force in changing from tube technology to transistors. The evolution of highly integrated chip technologies requires a broad understanding and use of EMC design experience.

As the technology progressed, legislation and standardization was developed to insure the harmony of the new sciences from an EMC standpoint.

Lets go back again to the German example. In 1927 the first edition of the "Deutsche Hochfrequenzgerätegesetz" was published. The recommendations of Chancellor Müller were successfully introduced although it took about 7 years to result in an official law. The new law was revised several times and was matched to the technical progress. This law was valid until December 31 of 1995 and was then replaced by the German EMC law, which is based on the European Directive.

Every product's reliability depends on EMC
No electrical product or installation can be designed seriously unless all aspects of EMC are taken into account. This is not only important for common products such as radios, evision sets, computers, ephones, washing machines, etc., but it is also especially important for complex products such as vehicles, aircraft, ships and large industrial installations. These are very sensitive to EMC problems and no one wants to accept serious disturbances within a big chemical plant.

Because of all the efforts made and being made to insure EMC compatibility, people start to believe that, after a certain time, all products are safe and immune. Sorry, but this has not come true as yet. Each new generation of engineers and technicians are again challenged by the issue of EMC with each new product and within each new installation. Practical solutions to EMC problems are not taught at universities. This can only be achieved with many years of experience in the field and testing. This is where EM Test can be of help.

EM Test has the task of educating engineers and technicians about EMC. EM Test can use its EMC experience to help all. Remember how this very interesting technical field began and developed. Only those who know the sources, and our sources are the basics of EMC, know where he has to go. We know the issues from the very beginning and will support you so that you better understand them. Let's go together a part of this way and let's keep in contact. By reading this message you have completed the first step.
電(dian)磁兼(jian)容(rong)性-定(ding)義
EMC指的(de)只(zhi)是(shi)“電(dian)子產品或(huo)電子(zi)產品在其環(huan)境中(zhong)的(de)工(gong)作(zuo)原(yuan)理(li)”。電(dian)子(zi)或(huo)電氣(qi)產(chan)品不應(ying)產(chan)生(sheng)電磁幹(gan)擾(rao)，可能(neng)影響(xiang)其他(ta)產品。換(huan)句話(hua)說(shuo)，EMC涉(she)及(ji)電(dian)子(zi)電(dian)氣(qi)產(chan)品和系統(tong)的(de)噪聲發(fa)射(she)和(he)抗噪聲問(wen)題(ti)。電(dian)磁幹(gan)擾(rao)主(zhu)要(yao)表(biao)現為(wei)傳導(dao)幹(gan)擾(rao)和輻(fu)射(she)發(fa)射和免(mian)疫(yi)問題(ti)。
壹(yi)般(ban)來說(shuo)電(dian)磁兼(jian)容(rong)，電磁兼(jian)容(rong)性，真(zhen)的(de)不(bu)難(nan)理(li)解(jie)，但(dan)妳知(zhi)道(dao)，魔鬼是在細(xi)節(jie)。讓(rang)我們更(geng)詳(xiang)細(xi)地(di)解(jie)釋(shi)壹(yi)下這個(ge)話(hua)題(ti)。對(dui)於(yu)妳們(men)這(zhe)些(xie)EMC專(zhuan)家來(lai)說(shuo)，我(wo)們希望妳們(men)原(yuan)諒(liang)我們進(jin)行壹些(xie)“非(fei)科(ke)學”的(de)簡化。
EMC這(zhe)個(ge)詞(ci)不(bu)包括電磁波（無(wu)論是期(qi)望的(de)還(hai)是(shi)不(bu)希望的(de)）對(dui)生(sheng)物系統(tong)的(de)影響(xiang)。這是(shi)壹個(ge)更(geng)大(da)的(de)領域，由(you)“東蒙(meng)大(da)拿教(jiao)育學院”（“E”是(shi)環境），這(zhe)不(bu)是今(jin)天的(de)主(zhu)題(ti)，也(ye)不(bu)在EM測(ce)試工作(zuo)的(de)領域。

EMC在哪裏開始(shi)的(de)
電(dian)磁兼(jian)容(rong)的(de)歷(li)史(shi)
讓(rang)我們回到EMC的(de)歷(li)史(shi)。電(dian)磁兼(jian)容(rong)比妳想象(xiang)的(de)要(yao)老。
我們都生(sheng)活在我們的(de)歷(li)史(shi)中(zhong)。EMC也(ye)是(shi)如(ru)此。妳可(ke)能(neng)不知(zhi)道(dao)，很多(duo)EMC專(zhuan)家也(ye)不(bu)知(zhi)道(dao)，壹切都是(shi)怎(zen)麽(me)開始(shi)的(de)。我(wo)們(men)想給(gei)妳簡要(yao)介紹(shao)壹(yi)下歐洲(zhou)電(dian)磁兼(jian)容(rong)的(de)歷(li)史(shi)。下面的(de)內容(rong)並(bing)不(bu)是非常(chang)詳(xiang)細(xi)的(de)，但(dan)它(ta)確實說(shuo)明了我(wo)們今(jin)天在EMC世界中(zhong)的(de)地(di)位。

歐(ou)洲(zhou)的(de)新(xin)通(tong)訊時代(dai)開始(shi)於(yu)1892年，當時德(de)國議會投票(piao)決(jue)定建立德(de)意(yi)誌帝國的(de)《電(dian)報法》。這(zhe)是(shi)世界上*條處理(li)電(dian)報技術領域中(zhong)電磁幹(gan)擾(rao)對(dui)產(chan)品(pin)和(he)裝(zhuang)置影響(xiang)的(de)法律。該法還(hai)規定了在發現電磁幹(gan)擾(rao)的(de)情(qing)況(kuang)下應(ying)遵(zun)循的(de)程序。當時的(de)人(ren)們(men)很(hen)快就發現電纜(lan)確實互相幹(gan)擾(rao)。電報和(he)通信的(de)幹(gan)擾(rao)zui為(wei)嚴重(zhong)。對(dui)電(dian)工(gong)的(de)德(de)國社會，成立於(yu)1893，是(shi)*的(de)VDE是(shi)什麽今(jin)天的(de)基(ji)礎(chu)。Wilhelm von Siemens是(shi)這個(ge)社會的(de)創(chuang)始人(ren)之(zhi)壹(yi)。

110多年前EMC並(bing)不(bu)是壹件(jian)大(da)事(shi)，但(dan)在1920 12月22日的(de)晚(wan)上，這種(zhong)情(qing)況(kuang)立即改(gai)變了。在這個(ge)晚(wan)上，KöNIG Wusterhausen東南(nan)柏林電臺(tai)播(bo)出的(de)德(de)國郵政(zheng)官(guan)員(yuan)的(de)聖(sheng)誕(dan)音(yin)樂會。這場(chang)音樂會是壹(yi)個(ge)生(sheng)活事(shi)件和觀(guan)眾(zhong)包括德(de)國總理(li)Hermann Müller，誰(shui)是(shi)接(jie)近(jin)演唱會地(di)點在的(de)KöNIG武(wu)斯特(te)豪(hao)森城堡。校長對(dui)過(guo)路車輛(liang)產生(sheng)的(de)電(dian)噪音幹(gan)擾(rao)不甚(shen)感(gan)興趣(qu)，他下令立即阻止(zhi)這(zhe)種(zhong)幹(gan)擾(rao)。“輻射(she)發(fa)射(she)”的(de)時間(jian)已經到來，後(hou)來(lai)稱為(wei)電磁兼(jian)容(rong)。

電磁兼(jian)容(rong)標(biao)準化
走(zou)向標(biao)準化的(de)*步(bu)…
德(de)國是zui先(xian)認識(shi)到需(xu)要(yao)防止和解決(jue)輻射(she)排放(fang)問題(ti)的(de)國家之(zhi)壹。1933、輻(fu)射委(wei)員會，更(geng)好(hao)地(di)稱(cheng)為(wei)CISPR成立。60年底，就電氣(qi)產(chan)品的(de)豁(huo)免問題(ti)進(jin)行了具體調查(zha)。1973電(dian)工委(wei)員會，IEC，成立了技術委(wei)員會TC77其職(zhi)能(neng)是制(zhi)定相關的(de)電(dian)磁兼(jian)容(rong)標(biao)準。

在第二次(ci)世(shi)界大(da)戰中(zhong)，電磁波的(de)知(zhi)識和(he)它(ta)們制(zhi)造幹(gan)擾(rao)的(de)能(neng)力被(bei)使用了。戰(zhan)爭(zheng)期(qi)間，雷(lei)達技術得(de)到發(fa)展。無(wu)線(xian)、電視、等新(xin)的(de)通(tong)信技術不僅(jin)要(yao)求(qiu)電磁兼(jian)容(rong)，而且(qie)是從(cong)管(guan)技術向晶體(ti)管轉換(huan)的(de)驅動(dong)力。高度集(ji)成的(de)芯(xin)片(pian)技術的(de)發(fa)展需(xu)要(yao)廣(guang)泛(fan)理(li)解(jie)和(he)使用EMC設(she)計經(jing)驗(yan)。

隨著(zhe)技術的(de)進(jin)步(bu)，立法和(he)標(biao)準化的(de)發(fa)展，以(yi)確保(bao)和(he)諧的(de)新(xin)科(ke)學，從(cong)EMC的(de)立場(chang)。

讓我(wo)們(men)再回到德(de)國的(de)例(li)子中(zhong)。1927的(de)*個(ge)版(ban)本(ben)的(de)“德(de)意(yi)誌hochfrequenzgerätegesetz”出版(ban)。校長ü建議M ller成(cheng)功(gong)引進(jin)了雖然(ran)大(da)約花(hua)了7年的(de)結果(guo)在壹個(ge)正(zheng)式的(de)法律。新(xin)法律修訂了幾(ji)次(ci)，與(yu)技術進(jin)步(bu)相匹(pi)配(pei)。該法有(you)效(xiao)期(qi)至1995 12月31日，其後(hou)由(you)德(de)國EMC法取代(dai)，該法以(yi)歐洲指令為(wei)基(ji)礎(chu)。

每(mei)個(ge)產(chan)品(pin)的(de)可(ke)靠(kao)性(xing)取決(jue)於EMC。
除(chu)非(fei)考(kao)慮到EMC的(de)所(suo)有(you)方(fang)面，否(fou)則不(bu)能(neng)認真(zhen)設計電(dian)氣(qi)產(chan)品或(huo)安(an)裝(zhuang)。這不僅(jin)對(dui)收音機、電視機、計算機(ji)、、洗衣機(ji)等(deng)常(chang)見(jian)產(chan)品很重要(yao)，而且對(dui)諸(zhu)如(ru)汽(qi)車(che)、飛(fei)機(ji)、輪(lun)船和(he)大(da)型工業(ye)裝(zhuang)置等(deng)復雜產(chan)品(pin)也(ye)特(te)別重要(yao)。這些(xie)對(dui)EMC問(wen)題(ti)非(fei)常(chang)敏(min)感(gan)，沒有(you)人(ren)願(yuan)意接(jie)受(shou)大(da)型化工(gong)廠(chang)的(de)嚴重(zhong)幹(gan)擾(rao)。

由於(yu)所(suo)有(you)的(de)努力(li)和確保(bao)EMC兼(jian)容(rong)性的(de)努力(li)，人們開始(shi)相信，經(jing)過(guo)壹定(ding)時間(jian)，所(suo)有(you)產(chan)品(pin)都(dou)是(shi)安(an)全(quan)和免疫(yi)的(de)。對(dui)不(bu)起(qi)，這(zhe)還(hai)沒有(you)實現。每(mei)壹代(dai)的(de)工(gong)程師和技術人員都再次(ci)受(shou)到電磁兼(jian)容(rong)問題(ti)的(de)困(kun)擾(rao)。大(da)學不教(jiao)授電(dian)磁兼(jian)容(rong)問題(ti)的(de)實際解決(jue)方(fang)案(an)。這只(zhi)能(neng)通過(guo)多年的(de)實地(di)經(jing)驗和測(ce)試來實現。這是(shi)EM測(ce)試可以(yi)幫(bang)助的(de)地(di)方(fang)。

電磁測(ce)試對(dui)工(gong)程技術人員進(jin)行電磁兼(jian)容(rong)教(jiao)育。EM測(ce)試可以(yi)利(li)用它(ta)的(de)EMC經(jing)驗(yan)來(lai)幫(bang)助所有(you)人(ren)。記(ji)住(zhu)這(zhe)個(ge)非(fei)常(chang)有(you)趣(qu)的(de)技術領域是(shi)如何(he)開始(shi)和(he)發展起(qi)來(lai)的(de)。只(zhi)有(you)那(na)些(xie)知(zhi)道(dao)來源和我(wo)們(men)的(de)來(lai)源是EMC的(de)基(ji)礎(chu)，知(zhi)道(dao)他必須(xu)去(qu)哪裏。我(wo)們從(cong)壹(yi)開始(shi)就知(zhi)道(dao)問題(ti)，並(bing)會支持妳，以(yi)便(bian)妳更(geng)好(hao)地(di)理(li)解(jie)它(ta)們。讓(rang)我(wo)們(men)壹起(qi)走(zou)這(zhe)條路的(de)壹(yi)部(bu)分(fen)，讓(rang)我(wo)們(men)保(bao)持。通(tong)過閱讀(du)這條信息(xi)，妳已經完(wan)成了*步(bu)。