Providing uninterrupted and undistorted power supply is essential due to increasing use of sensitive electronic devices which could malfunction under poor quality of power supply. Voltage flicker is one
power quality issue which can arise due to fluctuating electrical loads or due to intermittent power
sources such as solar and wind energy systems. Voltage flicker can manifest as repeated fluctuations
in indoor light intensity which can cause health issues. Voltage flicker can also lead to malfunction of
sensitive electronic equipment. Measurement of flicker is important to design flicker mitigation methodologies and to verify the effectiveness of the implemented flicker mitigation steps. International Electro Technical Commission (IEC) 61000-4-15 standard defines a method to quantify and measure the flicker level.
In order to continuously monitor the flicker level, power utilities install Flicker meters. In modern
digital substations that follow IEC 61850 standard for substation automation, the conventional analog
electrical signals are replaced with digitized sample values as defined in IEC 61850-9-2 standard.
Hence, a Flickermeter installed in such a substation need to rely on sampled values instead of the
analog voltage signals from instrument transformers.
This paper investigates the possibility of implementing an IEC Flickermeter based on IEC 61850-9-2
sampled values. The Flickermeter was successfully implemented on a RTDS real time simulator
with GTNET card, and its performance was confirmed using the standard test signals prescribed in
the IEC 61000–4–15 standard. The effects of the merging unit and the communication network
performance on flicker calculation were evaluated. The tests showed that the bit resolution of the
merging unit analog to digital converter and the packet losses in the communication network have
significant impact on the accuracy of the Flickermeter. Flickermeter implemented on the real time
digital simulator was used to analyze the flicker contribution from an arc furnace to a simple power
system. The investigation presented in this paper shows that a Flickermeter based on sampled values
can perform satisfactorily with commercial merging units and a reliable communication network.
J. WIJEKOON, A.D. RAJAPAKSE, N. PERERA , C. ADEWOLE, In Proc. Cigre Canada 2019, Montreal, QC, September 2019
KEYWORDS: Flickermeter, IEC 61000-4-15, IEC 61850, Power Quality, Real Time Digital Simulator, Sampled