Recently, interest in the power quality of the AC system is increasing due to the spread of distributed power sources such as solar power generation
and wind power generation, the spread and expansion of power electronic application devices, and the diversification of load facilities.
By monitoring and analyzing the power quality, it is possible to prevent system damage and interruption in advance,
and it is easier to find a solution by isolating the problem area separately in the future.
If a power quality meter is installed and continuously monitored, managers can respond more actively to power quality problems,
and prevent problems in productivity and business revenue loss caused by downtime and production loss in advance.
In the case of alternating current, power quality means transient voltage and current, individual waveform capture, harmonic distortion,
sag and swell, frequency fluctuation, and power factor that are out of a predetermined range and affect the operation of electronic devices.
Regarding the definition of these parameters, the International Electrotechnical Commission (IEC) has been working on a
measurement method for quality parameters related to AC power, and currently IEC 61000-4-30 Class A and Class S,
IEC61000-4- 7 Harmonic measurements and flicker are defined in IEC61000-4-15,
and most utilities have adopted these power quality standards.