Tugas 4

Analysis on the Dielectric Characteristics of Solid

Insulation Materials in LN2 for Development

of High Voltage Magnet Applications

Abstract

Several types of solid materials are used in the developmentof high voltage superconducting magnet systems as the former and insulation barrier. The solid insulation materialsused in cryogenic applications require excellent dielectric characteristicsas well as robust mechanical characteristics. In thisstudy, the dielectric experiments for three types of solid insulation materials, including glass fiber reinforced plastic (GFRP), epoxy(Stycast 2850FTJ), and Bakelite in liquid nitrogen (LN2) at 77 Ktemperature are performed. Each experiment on the solid insulation materials is performed according to the type of applied voltage (lightning impulse and ac voltage) and the system pressure (0.1 ∼ 0.4 MPa). Also, experiments considering the stacking effect of insulation sheets are performed. All electrical breakdown voltages are observed when the solid insulation materials are fully penetrated. Electrical breakdown experiments on GFRP and Bakelite sheets according to the number of stacking are performed and the results are compared. The relationship between the dielectric characteristics of solid insulation materials and the distribution of electric field intensity is calculated and analyzed by the finite elements method (FEM). The results revealed that the dielectric characteristics of solid insulation materials in LN2 are directly affected by the distribution of electric field intensity and thenumber of stacking sheets.

Index Terms—Bakelite, dielectrihttp://images.zwani.com/graphics/animated/images/animated119.gifc characteristics, GFRP, solid insulator, stacking, Stycast.

 Analisis Karakteristik Dielektrik Solid  Bahan Isolasi di LN2 untuk Pengembangan  
Aplikasi  Magnet  Tegangan Tinggi 

Beberapa jenis bahan padat yang digunakan dalam sistem tegangan tinggi super konduktor magnet pengembangan sebagai isolasi penghalang. Isolasi padat material dalam aplikasi cryogenic membutuhkan kharacteristicsas dielektrik yang sangat baik serta sifat mekanik yang kuat. Pada penelitian ini, percobaan dielektrik untuk tiga jenis bahan isolasi padat, termasuk diperkuat serat gelas plastik (GFRP), epoxy (Stycast 2850FTJ), dan Bakelite dalam nitrogen cair (LN2) pada 77 temperature dilakukan. Setiap percobaan pada bahan isolasi padat dilakukan sesuai dengan jenis tegangan yang diberikan (impuls petir dan tegangan ac) dan tekanan sistem (0,1 ~ 0,4 MPa).  percobaan mempertimbangkan efek susun lembaran isolasi dilakukan. Semua tegangan breakdown listrik diamati ketika bahan isolasi padat sepenuhnya ditembus. Percobaan kerusakan listrik pada GFRP dan Bakelite lembar sesuai dengan jumlah penumpukan dilakukan dan hasilnya dibandingkan. Hubungan antara karakteristik dielektrik bahan isolasi padat dan distribusi intensitas medan listrik dihitung dan dianalisis dengan metode elemen hingga (FEM). Hasil penelitian menunjukkan bahwa karakteristik dielektrik bahan isolasi padat di LN2 secara langsung dipengaruhi oleh distribusi intensitas medan listrik dan the number lembar susun. Indeks Syarat-Bakelite, karakteristik dielektrik, GFRP, isolator padat, susun, Stycast.

  

REFERENCES

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