EMC simulations - Application of simple antenna models to represent electromagnetic generators in vehicles 2008-36-0050
Nowadays, electromagnetic compatibility (EMC) has taken an important role in automotive development. This is because the effects that EMC can cause in a vehicle or on the environment. All systems contained in a vehicle emit EMC, and can be influenced by it also. During the vehicle design phase some variables have to be considered and improved to make the vehicle to be electromagnetic compatible.
We can list the vehicle systems as electromagnetic generators or victims, as below:
GPS transmission system
Mobile phone transmission system
Control modules (BCM, ECM, etc.)
An example of a complete system subject to the EM effects is the X-by-wire (or drive-by-wire) system, where mechanical systems are substituted by modules, cables, sensors, actuators. This system has to be designed considering electromagnetic compatibility.
The main tools to test the EMC on systems or full vehicles are:
Anechoic or reverberant chambers
The first option is more expensive and usually can be applied only at the final phases of vehicle development, when a concrete prototype is available. That way, the design engineers do not have enough time to work on the corrections of some eventual EMC problem, due to the fact the design stage is close to the end.
Computing simulation can be applied very earlier than measurement in chambers, because it only needs the mathematical model that usually is available on the first steps of vehicle development. Considering this affirmative, we will present some topics about vehicular electromagnetic environment simulations:
CAD math model importing
CAE modeling (Finite Elements Model)
Boundary conditions definition
Processing (Computing resource)
As complementary topic will be presented a mathematical concept to represent virtual electromagnetic generators, the so called “Equivalent Radiated Emission Source”, usually represented as a single loop antenna, that are developed based on bench (real) measurements. This concept simplifies the EM modeling and requires less computer resources to analyze the model.