【電磁技術在線】【EMC篇】- 1. EMC概覽
講師：Andreas Barchanski
01：30 EMC仿真概覽
04：00 電路EMC案例
09：00 三維EMC概覽
13：40 總體EMC流程
16：40 EMC應用：
輻射與耐受，大電流注入（BCI），屏蔽，靈敏度劣化，電擊，EMP， 共址干擾。
As all of you know, EMC compliance is crucial for releasing products to the market. Without compliance to EMC Standards, that are defined by legal bodies like for example the FCC or some European commission a product can not be sold in the given country. Furthermore, OEM’s like for example Car or Aerospace manufacturers might have their own, even more strict standard imposed on their suppliers.
In the past, EMC engineering was typically associated with measurements, only. It was applied late in the design stage as it required a working prototype. When problems appeared in the tests, a lot of effort was spend on trouble shooting by applying some counter measures in order to pass the test. Often the source ofthe problem was undetected and only the symptoms were mitigated. This approach can be very cost intensive as changes to the design at a late stage of the design process require a very high effort. In the worst case the time to the market of the product can be delayed not only causing increasing cost but also problems to the relation with your customer.
In general, there are two EMC simulations in the design process. First process is during the design stage, in which simulation can accompany the design process and be employed at an early design stage, give answers to fundamental “what if” questions and also can deliver output not accessible by measurements, without a prototype. The second process is to troubleshot at later stage, then simulation can also help to understand behavior of the device. Simulation is not a competitor to measurements, both should be used as complementary.
In another way, EMC simulation can be done in combination of 3D and circuit simulator，which both advantages can be used. The circuit simulate faster, but priori knowledge of coupling path is required. 3D simulation can take the coupling effect automatically and, but slower and passive. Thus, combine circuit and full-wave simulation to get best of both worlds !
Combine result is based on the superposition principle: 3D monitor results are calculated for each port separately, and circuit simulator calculates the (complex valued) voltages andcurrents at all pins of the 3D block. These values are then used to superposition the frequency domain field monitors in 3D. Much faster than a full 3D simulation.
Emission
oConducted emission
oRadiated emission
oShielding effectiveness
oEmission from cables
Susceptibility
oElectro static discharge
oRadiated immunity
oSurge / Electric fast transients
oBulk current injection
