• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

Difference in discharge threshold voltage on spacecraft solar array panel between vacuum ultra violet and electron beam

Research Project

Project/Area Number 19K04839
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeMulti-year Fund
Section一般
Review Section Basic Section 24010:Aerospace engineering-related
Research InstitutionKyushu Institute of Technology

Principal Investigator

Toyoda Kazuhiro  九州工業大学, 大学院工学研究院, 教授 (10361411)

Project Period (FY) 2019-04-01 – 2022-03-31
Project Status Completed (Fiscal Year 2021)
Budget Amount *help
¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000)
Fiscal Year 2021: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2020: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2019: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
Keywords帯電放電 / 表面電位 / 放電閾値 / ポッケルス効果 / 宇宙用太陽電池 / 表面電位分布計測 / 宇宙機帯電 / 表面電位計測 / 宇宙機太陽電池パネル / 真空紫外線 / 電子ビーム
Outline of Research at the Start

静止軌道での表面帯電では、紫外線による光電子電流と宇宙プラズマによる数十keVまでの電子が支配的となるが、近年行った実験では電子ビームを用いた時よりも紫外線を使用した方が閾値電圧が低くなるという結果を得た。閾値電圧が異なると放電のエネルギーが違うため、帯放電試験に影響を与えることになる。
本研究では、紫外線と電子ビームでの閾値の違いを明らかにすることを目的としている。実験では、放電閾値に影響を与えると考えれらるカバーガラス端面の表面電位をマイクロメーターのオーダーで計測することで評価する。これはポッケルス効果を用いた光計測によって実現する。また数値解析でも帯電の様子を明らかにする。

Outline of Final Research Achievements

In geostationary orbit, satellites are charged and discharged by ultraviolet rays and electrons, so discharge generation threshold measurements are performed as a countermeasure before launch. Recent experiments have shown that the discharge threshold voltage on solar cells is lower when ultraviolet rays are used than when electron beams are used. To clarify the cause of this, we used the Pockels effect to measure the surface potential at the edge of the coverglass in detail.
A two-dimensional distribution of the surface potential was obtained using a surface potential measurement system based on the Pockels effect, which was constructed using a Pockels element that changes its refractive index depending on the electric field. We were also able to confirm the difference in the surface charge distribution between UV and electron beams. Furthermore, the difference was also clarified by the charging analysis tool.

Academic Significance and Societal Importance of the Research Achievements

打ち上げ前に実施している太陽電池パネルの帯電放電試験では、放電のエネルギーを決定する放電閾値電圧が非常に重要となる。帯電の原因となる電子と紫外線で放電閾値電圧が異なることを実験的に明らかにし、その原因がカバーガラス端近傍の表面電位分布の違いにあると推測し、今回ポッケルス効果を用いて原因を明らかにした。ポッケルス効果により詳細な表面電位分布を得ることは学術的に意義があり、今後もこの計測方法を利用して新たな問題を解決できる。また、地上試験で紫外線と電子ビームのどちらを使用するべきかを明らかにしたこで社会的に大きな意義があった。

Report

(4 results)
  • 2021 Annual Research Report   Final Research Report ( PDF )
  • 2020 Research-status Report
  • 2019 Research-status Report
  • Research Products

    (6 results)

All 2022 2021 2020 2019

All Presentation (6 results) (of which Int'l Joint Research: 4 results)

  • [Presentation] Difference in threshold voltage of arc inception between electron beam and ultraviolet environment: surface potential measurement with Pockels effect2022

    • Author(s)
      Toyoda, K., Kose, S., and Cho, M.
    • Organizer
      Scitech forum 2022
    • Related Report
      2021 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Surface potential measurement with Pockels effect under electron beam and vacuum ultraviolet environment2022

    • Author(s)
      Kazuhiro Toyoda, Masaki Takuma, Sayaka Kose, and Mengu Cho
    • Organizer
      16th Spacecraft Charging Technology Conference
    • Related Report
      2021 Annual Research Report
    • Int'l Joint Research
  • [Presentation] 宇宙用太陽電池におけるポッケルス効果を用いた表面電位測定2021

    • Author(s)
      豊田 和弘,古瀬 清郁,琢磨 誠幸
    • Organizer
      第65回宇宙科学技術連合講演会
    • Related Report
      2021 Annual Research Report
  • [Presentation] Difference in threshold voltage of arc inception between electron beam and ultraviolet environment2020

    • Author(s)
      Kazuhiro Toyoda, Sayaka Kose, Takaaki Sasaki and Mengu Cho
    • Organizer
      AIAA Scitech 2020 Forum
    • Related Report
      2020 Research-status Report
    • Int'l Joint Research
  • [Presentation] Difference in threshold voltage of arc inception between electron beam and ultraviolet environment2020

    • Author(s)
      Kazuhiro Toyoda, Sayaka Kose, Takaaki Sasaki, Mengu Cho
    • Organizer
      AIAA Scitech 2020 forum
    • Related Report
      2019 Research-status Report
    • Int'l Joint Research
  • [Presentation] 宇宙用太陽電池におけるポッケルス効果を用いた表面電位測定システムの検討2019

    • Author(s)
      古瀬清郁  豊田和弘  趙 孟佑
    • Organizer
      宇宙環境シンポジウム
    • Related Report
      2019 Research-status Report

URL: 

Published: 2019-04-18   Modified: 2023-01-30  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi