TY - GEN
T1 - Quantifying the Probability of Partial Discharge in VFD Fed Electric Motors under Voltage Harmonics Concentration
AU - Hassan, Waqar
AU - Hussain, Ghulam Amjad
AU - Mahmood, Farhan
AU - Akmal, Muhammad
N1 - Hassan, W., Hussain, G. A., Mahmood, F., & Akmal, M. (2022, May). Quantifying the Probability of Partial Discharge in VFD Fed Electric Motors under Voltage Harmonics Concentration. In 2022 20th International Conference on Harmonics & Quality of Power (ICHQP), (pp. 1-6). IEEE.
PY - 2022
Y1 - 2022
N2 - Partial discharges (PD) diagnostics are considered as reliable techniques for the insulation health assessment of various electrical components of the power system. Generally, PD diagnostic tests are performed in laboratory by ignoring the effect of harmonic pollution in test voltage waveform. However, the operation of electric motors (EMs) fed by variable frequency drives (VFD) produces harmonic distortion in the sinusoidal test voltage waveform. During low speed operation of VFD, the influence of harmonic distortion in test voltage waveform is increased. The additional distortion parameters in the test voltage waveform can significantly increase the PD activity in the EM insulation. Therefore, for correct understanding of PD data, it is essential to consider the actual harmonic spectrum of the test voltage waveform during online PD measurement. This paper presents a methodology for the quantification of the probability of PD in VFD-fed EMs under different concentration of voltage harmonics. For the experimental work, PD diagnostic tests have been performed under variable operating conditions of eight EMs and PD severity is investigated by calculating the PD characteristic parameters at different harmonic distortion levels. Also, the probability density functions and cumulative distribution functions for several probability distributions were evaluated to statistically process the PD data at different harmonic levels. Finally, the distribution fitting tools have been implemented to find an appropriate distribution that can precisely characterize the probability of PD under different concentration of voltage harmonics. The proposed method may be utilized for studying the effect of harmonic distortion on PD activity and estimating the lifetime of stator insulation in EMs.
AB - Partial discharges (PD) diagnostics are considered as reliable techniques for the insulation health assessment of various electrical components of the power system. Generally, PD diagnostic tests are performed in laboratory by ignoring the effect of harmonic pollution in test voltage waveform. However, the operation of electric motors (EMs) fed by variable frequency drives (VFD) produces harmonic distortion in the sinusoidal test voltage waveform. During low speed operation of VFD, the influence of harmonic distortion in test voltage waveform is increased. The additional distortion parameters in the test voltage waveform can significantly increase the PD activity in the EM insulation. Therefore, for correct understanding of PD data, it is essential to consider the actual harmonic spectrum of the test voltage waveform during online PD measurement. This paper presents a methodology for the quantification of the probability of PD in VFD-fed EMs under different concentration of voltage harmonics. For the experimental work, PD diagnostic tests have been performed under variable operating conditions of eight EMs and PD severity is investigated by calculating the PD characteristic parameters at different harmonic distortion levels. Also, the probability density functions and cumulative distribution functions for several probability distributions were evaluated to statistically process the PD data at different harmonic levels. Finally, the distribution fitting tools have been implemented to find an appropriate distribution that can precisely characterize the probability of PD under different concentration of voltage harmonics. The proposed method may be utilized for studying the effect of harmonic distortion on PD activity and estimating the lifetime of stator insulation in EMs.
KW - Electric machines (EMs)
KW - harmonics
KW - partial discharges (PD)
KW - power quality (PQ)
KW - probability distribution
KW - variable frequency drives (VFD)
UR - http://www.scopus.com/inward/record.url?scp=85133730657&partnerID=8YFLogxK
U2 - 10.1109/ICHQP53011.2022.9808627
DO - 10.1109/ICHQP53011.2022.9808627
M3 - Conference contribution
T3 - Proceedings of International Conference on Harmonics and Quality of Power, ICHQP
BT - ICHQP 2022 - 2022 20th International Conference on Harmonics and Quality of Power
PB - IEEE Computer Society
T2 - 20th International Conference on Harmonics and Quality of Power, ICHQP 2022
Y2 - 29 May 2022 through 1 June 2022
ER -