15 - Protecting from poor AC (mains) and DC power quality

Provides 1.5 hours towards CPD

Read more about CPD with EMC Standards


Protecting from poor power quality

This module helps engineers understand that mains power suffers from many electromagnetic disturbances....

– surges, spikes, transients, bursts of fast transients, electrostatic discharge, common-mode radio-frequency (RF) voltages and currents, etc...

– all of which are common to all conductors and are dealt with by our other course modules

This module covers ‘non-RF’ mains power quality issues. ie. Frequencies <150 kHz

The module is 80 slides over 40 pages


1) Introduction

2) Overvoltages (swells)

3) Frequency variations

4) 3-phase unbalance

5) DC in AC supplies

6) Common-Mode Low-Frequency voltages

7 ) Undervoltages
(sags, brownouts, dips, dropouts and interruptions)

8) Voltage fluctuations

9) Waveform distortion (harmonic and interharmonic)

10) Improving the quality of the mains supply itself

11) Tripping out

12) Some useful references



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