Combined Effect of Temperature and Humidity of Magnet-Wires on Partial Discharge Inception Voltage under Inverter-Surge Voltage

Kaji, Takefumi; Asai, Hiromitsu; Kojima, H.; Hayakawa, Naoki

doi:10.1109/ceidp.2018.8544745

Cited by 16 publications

(13 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To pursue high-performance EMs, understanding the physics of partial discharge is necessary instead of adopting the empirical enhancement factor. Many works dedicate to investigate the influence factors on PDIV or RPDIV of turn/turn insulation [54,62,120,123,[138][139][140][141][142][143][144][145][146][147][148][149][150][151][152][153] through experiments. A typical experiment setup for PDIV investigation is presented in Figure 11.…”

Section: Experiment-based Studies On Pdmentioning

confidence: 99%

“…Both temperature [54,62,120,123,[140][141][142]155] and pressure [120,138,[142][143][144]152,153] have great impact on the PDIV. In general, the PDIV decreases with the increase of temperature and the reduction of pressure.…”

Section: Effect Of Ambient Conditionsmentioning

confidence: 99%

“…The same method can be found in [134,152] where both temperature and pressure are considered. Humidity can also influence the PDIV, and the investigation on twisted pairs can be found both under ac voltage [121,140,145,156] and surge voltage [140]. No general tendency can be concluded since the effect of humidity may both depend on temperature [156] and voltage type [140].…”

Section: Effect Of Ambient Conditionsmentioning

confidence: 99%

“…Humidity can also influence the PDIV, and the investigation on twisted pairs can be found both under ac voltage [121,140,145,156] and surge voltage [140]. No general tendency can be concluded since the effect of humidity may both depend on temperature [156] and voltage type [140]. An attempt trying to explain the humidity effect on PDIV is given in [121] based on the relationship between space charge and PDIV presented in [157].…”

Section: Effect Of Ambient Conditionsmentioning

confidence: 99%

“…As stated in IEC 60034-18-41 [22], the insulation system can be both qualified using sinusoidal voltage or impulsive voltage. However, the study in [138,140,150,151,157,161,162] indicates that there could be a difference between PDIV measured by sinusoidal voltage and surge voltage, and the level of the inverter can have a strong influence [150,151]. Moreover, the polarity of the square wave may also impact PDIV [59,157,162].…”

Section: Effect Of Surge Voltage Characteristicmentioning

confidence: 99%

See 4 more Smart Citations

Reliability-Oriented Design of Inverter-Fed Low-Voltage Electrical Machines: Potential Solutions

Giangrande

Madonna³

et al. 2021

Energies

View full text Add to dashboard Cite

Transportation electrification has kept pushing low-voltage inverter-fed electrical machines to reach a higher power density while guaranteeing appropriate reliability levels. Methods commonly adopted to boost power density (i.e., higher current density, faster switching frequency for high speed, and higher DC link voltage) will unavoidably increase the stress to the insulation system which leads to a decrease in reliability. Thus, a trade-off is required between power density and reliability during the machine design. Currently, it is a challenging task to evaluate reliability during the design stage and the over-engineering approach is applied. To solve this problem, physics of failure (POF) is introduced and its feasibility for electrical machine (EM) design is discussed through reviewing past work on insulation investigation. Then the special focus is given to partial discharge (PD) whose occurrence means the end-of-life of low-voltage EMs. The PD-free design methodology based on understanding the physics of PD is presented to substitute the over-engineering approach. Finally, a comprehensive reliability-oriented design (ROD) approach adopting POF and PD-free design strategy is given as a potential solution for reliable and high-performance inverter-fed low-voltage EM design.

show abstract

Section: Experiment-based Studies On Pdmentioning

confidence: 99%

Section: Effect Of Ambient Conditionsmentioning

confidence: 99%

Section: Effect Of Ambient Conditionsmentioning

confidence: 99%

Section: Effect Of Ambient Conditionsmentioning

confidence: 99%

Section: Effect Of Surge Voltage Characteristicmentioning

confidence: 99%

See 3 more Smart Citations

Reliability-Oriented Design of Inverter-Fed Low-Voltage Electrical Machines: Potential Solutions

Giangrande

Madonna³

et al. 2021

Energies

View full text Add to dashboard Cite

show abstract

Investigation on combined effect of humidity–temperature on partial discharge through dielectric performance evaluation

Giangrande

Zhao

et al. 2022

IET Science Measure & Tech

View full text Add to dashboard Cite

The humidity role in the partial discharge (PD) inception mechanism is quite challenging, especially when considering the environmental temperature. Indeed, there is no general rule to explain the humidity effect on the PD phenomenon. In this paper, the PD activity in inter‐turn insulation is experimentally investigated for different relative humidity (RH) conditions at three different ambient temperatures, that is, 30°C, 60°C, and 90°C. Partial discharge inception voltage (PDIV) is directly measured through a photomultiplier tube (PMT), whereas the tip‐up tests are performed aiming at monitoring both dissipation factor (tanδ) and insulation capacitance (IC). These extra measurements (diagnostic dielectric markers) allow better assessing the insulation status. The adoption of the tip‐up test enables the insulation properties measurement. Based on the tip‐up tests’ findings, the interfacial polarization process starts at 75% RH under 60°C, while the high conductivity area is already formed at 75% RH when the ambient temperature is 90°C. The water film formation deduced from the tip‐up test is then used to explain the trend of PDIV, and the validity is further proved by finite element analysis (FEA).

show abstract

On the frequency dependence of the PDIV in twisted pair magnet wire analogy in humid air

Šefl,

Färber,

Franck

2024

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

The partial discharge inception voltage (PDIV) of low-voltage induction motor turn-turn insulation analogy is investigated for variable relative humidity of the surrounding air (temperature and pressure are kept constant close to their ambient values). Three materials, perfluoralkoxy alkane, sealed and unsealed alumina, are employed as the dielectric coating (insulation) of test samples. Each material’s dielectric properties change differently with relative humidity—of these, relative permittivity is regarded as the most crucial, as it was previously proven to be, along with the coating’s thickness, the key factor in determining the PDIV in dry air conditions. To further vary the value of permittivity and thus provide larger data sets for the verification study, the frequency of the excitation voltage is also varied between 1 Hz and 50 kHz. The obtained experimental data are compared against the PDIV predictions obtained by a breakdown model based on the reduced thickness of the coating (ratio of the coating thickness to its relative permittivity).Satisfying agreement between the measured and predicted PDIV are obtained for the first two materials, whereas significant discrepancies are seen for the unsealed alumina material. For this case, surface conductivity is introduced into the prediction model and much better fits to the experimental data are obtained for a suitable value of surface resistance. It is hence demonstrated that the model is able to satisfactorily predict the PDIV for three substantially different materials when the relative humidity of the surrounding air is varied between 10% to 80 %.

show abstract

Combined Effect of Temperature and Humidity of Magnet-Wires on Partial Discharge Inception Voltage under Inverter-Surge Voltage

Cited by 16 publications

References 5 publications

Reliability-Oriented Design of Inverter-Fed Low-Voltage Electrical Machines: Potential Solutions

Reliability-Oriented Design of Inverter-Fed Low-Voltage Electrical Machines: Potential Solutions

Investigation on combined effect of humidity–temperature on partial discharge through dielectric performance evaluation

On the frequency dependence of the PDIV in twisted pair magnet wire analogy in humid air

Contact Info

Product

Resources

About