What are the technical terms for electromagnetic compatibility
(1) Electromagnetic compatibility
Electromagnetic compatibility refers to the ability of the equipment or system to work properly in its electromagnetic environment, and does not constitute an intolerable electromagnetic nuisance to anything in that environment.
(2) Electromagnetic harassment
Electromagnetic harassment refers to any electromagnetic phenomenon that may cause equipment, equipment or system performance degradation or damage to living or non-living material. Electromagnetic harassment can cause degradation of equipment, transmission channel or system performance. Its main elements are natural and man-made sources of nuisance, coupling through the common ground impedance/internal resistance, electromagnetic nuisance conducted along the power line and radiated interference. The path of interference to the electronic system is: through the power supply, through the signal line or control cable, field penetration, through the antenna directly into; through the cable coupling, conducted interference from other equipment; electronic system internal field coupling; radiated interference from other equipment; external coupling to the internal field of electronic equipment; broadband transmitter antenna system; external environmental fields and so on.
(3) Electromagnetic Environment
Electromagnetic environment is a time-varying electromagnetic phenomenon that apparently does not transmit information, which may be superimposed or combined with useful signals.
(4) Electromagnetic Radiation
Electromagnetic radiation is a phenomenon in which electromagnetic waves are emitted from a source into space. The term "electromagnetic radiation" is sometimes extended to include the phenomenon of electromagnetic induction.RFI/EMI can be radiated through openings, vents, entrances, exits, cables, measurement holes, door frames, hatch covers, drawers, and panels of any type of equipment enclosure, as well as through non-ideal attachment surfaces of the enclosure. radiated by wires and cables entering sensitive equipment, and any good emitter of electromagnetic energy can also act as a good receiver.
(5) Pulse
An impulse is a physical quantity that changes abruptly over a short period of time and then returns quickly to its initial value.
(6) Common mode interference and differential mode interference
There are two types of interference on a power line, common mode interference and differential mode interference. Common mode interference exists between any one of the power supply to earth or wire to earth. Common mode interference is sometimes called longitudinal mode interference, asymmetrical interference or ground interference. This is interference between a current-carrying conductor and earth. Differential mode interference exists between the power supply phase and centre wires and between the phase and phase wires. Differential mode interference is also known as normal mode interference, transverse mode interference or symmetrical interference. It is interference between current-carrying conductors. Common mode interference suggests that the interference is coupled into the circuit by radiation or crosstalk, while differential mode interference suggests that the interference originates from the same power circuit. Often these two types of interference are present at the same time, and the situation is complicated by the fact that the two types of interference are also transformed into each other in transmission due to the imbalance of the line impedance. After transmission over long distances, the interference decays more in the differential mode component than in the common mode, due to the difference in line-to-line impedance and line-to-ground impedance. For the same reason, common mode interference also radiates into neighbouring space during line transmission, whereas differential mode does not, so common mode interference is more likely to cause EMI than differential mode. Different methods of interference suppression should be adopted to be effective. An easy way to determine the interference method is to use a current probe. The current probe first individually around each wire, the inductance value of a single wire, and then around two wires (one of which is the ground), to detect the inductance of the situation. If the induced value is increasing, the interfering current in the line is common mode; conversely, it is differential mode.
