Interference Emissions And Interference Immunity; The Frequency Converter And Its Emc; The Frequency Converter As A Source Of Interference - Siemens SINAMICS G130 Engineering Manual

2.2.2

Interference emissions and interference immunity

Interference emissions
The interference emission is a type of interference emitted from the frequency converter to the environment.
High-frequency interference emissions from frequency converters are regulated by the EMC product standard
EN 61800-3, which defines limit values for:
·
High-frequency conducted interference at the supply system connection point (radio interference voltages)
·
High-frequency electromagnetically-radiated interference (interference radiation)
The defined limit values depend on the ambient conditions ("first" or "second" environment).
Low-frequency interference emissions from frequency converters (normally referred to as harmonic effects on the
supply system or supply system perturbation) are regulated by different standards. EN 61000-2-2 is applicable for
public low-voltage supply systems, while EN 61000-2-4 is applicable for industrial supply systems. Outside of Europe,
reference is often made to IEEE 519. The regulations of the local power supply company must also be observed.
Interference immunity
Interference immunity describes the behaviour of frequency converters under the influence of electromagnetic
interference, which affects the converter through the environment. Types of interference include:
High-frequency conducted interference (radio interference voltages)
High-frequency electromagnetic radiation (interference radiation)
The requirements and criteria for evaluating behaviour under the influence of these types of interference are also
regulated by the EMC product standard EN 61800-3.

2.3 The frequency converter and its EMC

2.3.1

The frequency converter as a source of interference

Method of operation of SINAMICS frequency converters
SINAMICS frequency converters comprise a line-side rectifier that supplies a DC link. The inverter connected to the
DC link generates an output voltage V (comprising virtually rectangular voltage pulses) from the DC link voltage using
the method of pulse-width modulation. The smoothing effect of the motor inductance generates a largely sinusoidal
motor current I.
Principles of operation of SINAMICS frequency converters and schematic representation of output voltage V and motor
current I
EMC Installation Guideline
Engineering Information
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