Polarisation and depolarisation current measurement (PDC) · สีเขียว =Model curveat moisture 3% Tx.25 MVA 115-22 kV. 22 5.Application of PDC. 23 EGAT Power for Thai

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Polarization and depolarization current measurement (PDC)

นาย สุทัศน' สุขสกุลป,ญญา

[email protected]

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ขอบเขตการนําเสนอ

• Dielectric response

• Moisture in transformer insulation

• Moisture assessment by electrical method

• Polarization and depolarization current measurement

• Application of PDC

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1.Dielectric response

Dielectric response คืออะไร

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1.Dielectric response

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1.Dielectric response

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1.Dielectric response

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1.Dielectric response

Measurement technique

Time domain Frequency domain

Polarization and depolarization current measurement (PDC)

Frequency domain spectroscopy (PDC)

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2.Moisture in transformer insulation

Cigre WG 12.8 Life management of transformers, 1999

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2.Moisture in transformer insulation

L.E. Lundgaard, “Aging of oil-impregnated paper in power transformer”, IEEE Transaction on Power Delivery, Jan. 2004

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2.Moisture in transformer insulation

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2.Moisture in transformer insulation

(Ryzhenko, V.Sokolov, V.: Effect of moisture on dielectric withstand strength of winding insulations in power transformer. Electrical stations (Electric power plants) No.9, 1981

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3. Moisture assessment by electrical method

• 1960+

• Dielectric loss at power frequency (%PF, %tan δ)

• Polarization index (PI)

• 1991 Recovery voltage measurement (RVM) (Tettex)

• 1999+ Polarization and depolarization current measurement (PDC)

(Alff Engineering)

• 1999+ Frequency domain spectroscopy (FDS) (ABB)

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4. Polarization and depolarization current measurement

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4. Polarization and depolarization current measurement

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4. Polarization and depolarization current measurement

Insulation

Homogeneous systems

Multi layer systems

Bushing Cable Instrument transformer

Generator Motor

Transformer

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4. Polarization and depolarization current measurementHomogeneous systems

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4. Polarization and depolarization current measurementMulti layer systems

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4. Polarization and depolarization current measurementMulti layer systems

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4. Polarization and depolarization current measurementMulti layer systems

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4. Polarization and depolarization current measurementMulti layer systems

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4. Polarization and depolarization current measurement

การวิเคราะห'ผลทดสอบ

Master curve หรือ Math model

Tx .25 MVA 115-22 kVสีเขียว = Model curve at moisture 3%

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5. Application of PDC

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