Partial discharge investigation and electric field analysis of different oscillation modes of water droplets on the surface of polymeric insulator under tangential AC electric field stress

Nazemi, M. H.; Hinrichsen, Volker

doi:10.1109/icsd.2013.6619788

Cited by 11 publications

(13 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These modes, named mode No.1 to mode No.4, are illustrated in Figure 6. Modes No.1 and No.3 were found to result in lower values of PD inception voltage in comparison with modes No.2 and No.4 [17].…”

Section: Oscillation Modesmentioning

confidence: 80%

“…The E-field value at the center of the test object can be considered as a constant value of E 0 = 0.41 kV/cm when applying a voltage U = 1 kV across the electrodes [17][18]. This applied E-field E 0 is considered as a scaling factor for conversion of measured PD inception voltages to PD inception E-field strengths.…”

Section: Conversion To Inception E-field Strengthsmentioning

confidence: 99%

See 1 more Smart Citation

Experimental investigations on partial discharge characteristics of water droplets on polymeric insulating surfaces at AC, DC and combined AC-DC voltages

Nazemi

Hinrichsen

2015

IEEE Trans. Dielect. Electr. Insul.

Self Cite

View full text Add to dashboard Cite

Water droplets on polymeric insulating surfaces provide an intensified E-field stress at the common interface between water droplet, insulating surface and surrounding air, which may lead to partial discharges, surface deterioration or even flashover. While intensive research has been performed for the AC case and also for the DC case, a new kind of stress may arise by the combination of both, which is present when a DC and an AC system are installed on the same tower. Water droplet deformations at AC, DC and combined AC-DC voltages as well as their PD characteristics are experimentally investigated and discussed in this contribution. The water droplet at AC voltage oscillates at different oscillation modes, while it elongates towards electrodes at DC voltage. The deformation under combined AC-DC voltage stress consists of an oscillation superimposed to an elongation towards the electrodes. The water droplet elongates towards the AC electrode when the polarity of DC source is negative, while it elongates towards the DC electrode in case of positive DC voltage. Oscillation modes of the water droplet at AC voltage have an influence on its PD inception E-field strength. Under DC stress the PD signals consist of two or more different PD levels which are due to the differently sharped edges of the deformed water droplet. Increasing the DC component at combined AC-DC voltage provides a lower PD inception E-field strength. Conductive water droplets have lower PD inception values in comparison with non-conductive ones under AC-DC stress.Index Terms -Water droplet, polymeric insulating surfaces, PD inception E-field strength and combined AC-DC voltage.

show abstract

Section: Oscillation Modesmentioning

confidence: 80%

Section: Conversion To Inception E-field Strengthsmentioning

confidence: 99%

Experimental investigations on partial discharge characteristics of water droplets on polymeric insulating surfaces at AC, DC and combined AC-DC voltages

Nazemi

Hinrichsen

2015

IEEE Trans. Dielect. Electr. Insul.

Self Cite

View full text Add to dashboard Cite

show abstract

“…The test object for an individual water droplet on an insulating surface under tangential electric field stress in this contribution is the same as that in previous works [6][7]. This setup consists of two highvoltage electrodes, which are embedded in insulating material plates from opposite sides (see Figure 1).…”

Section: Test Objectmentioning

confidence: 94%

“…In other words, considering the calculated maximum E-field value as a threshold of streamer discharge may have high uncertainties as the E-field enhancement factor at the triple line is strongly dependent on the software and its discretization (mesh) accuracy. On the other hand, the droplets' shape is dynamically deformed under the influence of dielectric forces resulting, typically, in different oscillation modes [6][7]. These deformations of a water droplet make it also difficult to estimate the droplet induced electric field enhancement on the insulator surface or to predict the partial discharge inception electric field strength.…”

Section: Introductionmentioning

confidence: 99%

“…The mechanism of pollution flashover of traditional porcelain or glass insulators can be explained considering the generated dry band areas over the insulator surface [2][3], but since there is no continuous wet layer on the surface of polymeric insulators, the mechanism of pollution flashover of this type of insulators is different from that of traditional porcelain or glass types. Water droplets forming on the hydrophobic surface of polymeric insulators give rise to significant electric field enhancement, especially in close vicinity to the contact line between surrounding air, water droplet and insulator surface [4][5][6][7], which may lead to partial discharges and even flashover. Due to this significant Efield enhancement, most of finite element based simulation approaches have a singularity problem when trying to find the maximum E-field strength value at the triple line.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Partial discharge inception electric field strength of water droplets on polymeric insulating surfaces

Nazemi

Hinrichsen

2015

IEEE Trans. Dielect. Electr. Insul.

Self Cite

View full text Add to dashboard Cite

Water droplets are formed on the surface of polymeric insulators under wet conditions, which enhance the electric field especially in close vicinity of the contact line between air, water droplet and insulator surface. It is experimentally found that the maximum allowable E-field strength tangential to a polymeric insulating surface in presence of a single water droplet on the flat surface with wettability class 1 is between 6 and 7.5 kV/cm (peak). Some important parameters that have an influence on PD inception are experimentally investigated to find more reliable results. A simple prediction method of partial discharge inception E-field strength of a single water droplet on polymeric insulating surfaces based on the streamer criterion for inception is also proposed and discussed. The investigated PD inception E-fields in this contribution can be used for prediction of partial discharge inception voltage of polymeric insulators under wet conditions.Index Terms -Water droplet, electric field, polymeric insulator, streamer inception and partial discharge inception.

show abstract

Understanding the water droplet initiated discharges on gamma irradiated silicone rubber insulation

Mishra

Gautam

Vinu

et al. 2018

Polymer Engineering & Sci

View full text Add to dashboard Cite

Corona inception voltage (CIV) due to water droplet on gamma‐irradiated silicone rubber indicates that its value reduces with increase of conductivity and with number of droplet in the electrode gap along the axis of the electrode. Increase in dosage of gamma irradiation to silicone rubber reduces the CIV. The UHF signal generated during corona inception due to water droplet has frequency bandwidth in the range of 0.3–1.2 GHz. The discharges occur in the phase range of 30°–130° in the positive half cycle and about 210°–270° in the negative half cycle. The water droplet shape gets altered on application of voltage. Surface charge accumulation studies indicate characteristic change with gamma irradiated specimen. In the presence of water droplet, the charge decay occurs rapidly with a single droplet and with three droplets. Thermal analysis of gamma radiation dosed samples reveals the destabilization of silicone material and the formation of higher order cyclic siloxane oligomers and oxygenated organics, which are expected to act as potential charge trapping sites. POLYM. ENG. SCI., 59:182–191, 2019. © 2018 Society of Plastics Engineers

show abstract

Partial discharge investigation and electric field analysis of different oscillation modes of water droplets on the surface of polymeric insulator under tangential AC electric field stress

Cited by 11 publications

References 5 publications

Experimental investigations on partial discharge characteristics of water droplets on polymeric insulating surfaces at AC, DC and combined AC-DC voltages

Experimental investigations on partial discharge characteristics of water droplets on polymeric insulating surfaces at AC, DC and combined AC-DC voltages

Partial discharge inception electric field strength of water droplets on polymeric insulating surfaces

Understanding the water droplet initiated discharges on gamma irradiated silicone rubber insulation

Contact Info

Product

Resources

About