EMC電磁兼容原理

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.
電磁兼容性-定義
EMC指的只是“電子產品或電子產品在其環境中的工作原理”。電子或電氣產品不應產生電磁干擾，可能影響其他產品。換句話說，EMC涉及電子電氣產品和系統的噪聲發射和抗噪聲問題。電磁干擾主要表現為傳導干擾和輻射發射和免疫問題。
一般來說電磁兼容，電磁兼容性，真的不難理解，但你知道，魔鬼是在細節。讓我們更詳細地解釋一下這個話題。對于你們這些EMC專家來說，我們希望你們原諒我們進行一些“非科學”的簡化。
EMC這個詞不包括電磁波（無論是期望的還是不希望的）對生物系統的影響。這是一個更大的領域，由“東蒙大拿教育學院”（“E”是環境），這不是今天的主題，也不在EM測試工作的領域。

EMC在哪里開始的
電磁兼容的歷史
讓我們回到EMC的歷史。電磁兼容比你想象的要老。
我們都生活在我們的歷史中。EMC也是如此。你可能不知道，很多EMC專家也不知道，一切都是怎么開始的。我們想給你簡要介紹一下歐洲電磁兼容的歷史。下面的內容并不是非常詳細的，但它確實說明了我們今天在EMC世界中的地位。

歐洲的新通訊時代開始于1892年，當時德國議會投票決定建立德意志帝國的《電報法》。這是世界上*條處理電報技術領域中電磁干擾對產品和裝置影響的法律。該法還規定了在發現電磁干擾的情況下應遵循的程序。當時的人們很快就發現電纜確實互相干擾。電報和通信的干擾zui為嚴重。對電工的德國社會，成立于1893，是*的VDE是什么今天的基礎。Wilhelm von Siemens是這個社會的創始人之一。

110多年前EMC并不是一件大事，但在1920 12月22日的晚上，這種情況立即改變了。在這個晚上，KöNIG Wusterhausen東南柏林電臺播出的德國郵政官員的圣誕音樂會。這場音樂會是一個生活事件和觀眾包括德國總理Hermann Müller，誰是接近演唱會地點在的KöNIG武斯特豪森城堡。校長對過路車輛產生的電噪音干擾不甚感興趣，他下令立即阻止這種干擾。“輻射發射”的時間已經到來，后來稱為電磁兼容。

電磁兼容標準化
走向標準化的*步…
德國是zui先認識到需要防止和解決輻射排放問題的國家之一。1933、輻射委員會，更好地稱為CISPR成立。60年底，就電氣產品的豁免問題進行了具體調查。1973電工委員會，IEC，成立了技術委員會TC77其職能是制定相關的電磁兼容標準。

在第二次世界大戰中，電磁波的知識和它們制造干擾的能力被使用了。戰爭期間，雷達技術得到發展。無線、電視、等新的通信技術不僅要求電磁兼容，而且是從管技術向晶體管轉換的驅動力。高度集成的芯片技術的發展需要廣泛理解和使用EMC設計經驗。

隨著技術的進步，立法和標準化的發展，以確保和諧的新科學，從EMC的立場。

讓我們再回到德國的例子中。1927的*個版本的“德意志hochfrequenzgerätegesetz”出版。校長ü建議M ller成功引進了雖然大約花了7年的結果在一個正式的法律。新法律修訂了幾次，與技術進步相匹配。該法有效期至1995 12月31日，其后由德國EMC法取代，該法以歐洲指令為基礎。

每個產品的可靠性取決于EMC。
除非考慮到EMC的所有方面，否則不能認真設計電氣產品或安裝。這不僅對收音機、電視機、計算機、、洗衣機等常見產品很重要，而且對諸如汽車、飛機、輪船和大型工業裝置等復雜產品也特別重要。這些對EMC問題非常敏感，沒有人愿意接受大型化工廠的嚴重干擾。

由于所有的努力和確保EMC兼容性的努力，人們開始相信，經過一定時間，所有產品都是安全和免疫的。對不起，這還沒有實現。每一代的工程師和技術人員都再次受到電磁兼容問題的困擾。大學不教授電磁兼容問題的實際解決方案。這只能通過多年的實地經驗和測試來實現。這是EM測試可以幫助的地方。

電磁測試對工程技術人員進行電磁兼容教育。EM測試可以利用它的EMC經驗來幫助所有人。記住這個非常有趣的技術領域是如何開始和發展起來的。只有那些知道來源和我們的來源是EMC的基礎，知道他必須去哪里。我們從一開始就知道問題，并會支持你，以便你更好地理解它們。讓我們一起走這條路的一部分，讓我們保持。通過閱讀這條信息，你已經完成了*步。