沿面アーク推進機の性能向上に向けた
電気二重層コンデンサの使用と矩形型の検討
九州工業大学 工学府 工学専攻 電気宇宙システム工学コース
223D5006 真如友洋 （指導教員：豊田和弘 教授）
九州工業大学では超小型衛星用電気推進機として沿面アーク推進機の開発を進めている．沿面アーク推進機は，電熱加速型の推進機で，ノイズを低減するために一定の低電流で駆動する．また，小型化を図るために固体推進剤を使用している．
電源回路において，コンデンサにはサイズが大きく高耐圧低容量であるアルミ電解コンデンサを，定電流を実現するためにバイポーラトランジスタを用いた定電流回路が使用されていた．初期の頃と比べ，大幅に小型化されたが，超小型衛星に搭載するにはまだ不十分である．本研究では，低耐圧だが，小型で大容量である電気二重層コンデンサを提案し，電源回路のダウンサイジングを図った．
これまで沿面アーク推進機は同軸型の推進機として性能試験が行われてきた．しかし，搭載できる推進剤が非常に少なく，放電がある 1 点に集中し，推進剤を十分に活用できていない．本研究では，放電を 1 点に定め，推進剤を多く搭載できるように，推進剤を矩形形状に変更することを試みた．

Use of Electric Double Layer Capacitor and Rectangular Typefor Performance Improvement of Surface Arc Thruster
Kyushu Institute of Technology, Graduate School of Engineering,Electrical and Space Systems Engineering Course
223D5006, Tomohiro Shinnyo (Supervisor: Prof. Kazuhiro Toyoda)
The Surface Arc Thruster (SAT) is an electric thruster designed for CubeSats by the Kyushu Institute ofTechnology. It is an electrothermal acceleration system that operates at a constant low current to minimize
electromagnetic interference. Additionally, the SAT uses solid propellant to make it more compact.t is used in
the SAT to make it more compact.
In power supply circuits, large-sized aluminum electrolytic capacitors with high withstand voltage and low
capacitance were traditionally used. Bipolar transistors were used in constant-current circuits to ensure a
uniform current flow. Although the power supply circuit has undergone significant downsizing compared toearlier versions, it remains inadequate for CubeSat applications. In this study, we propose using an electric
double-layer capacitor with a lower withstand voltage but a smaller size and higher capacitance to further reduce
the size of the power supply circuit.
The SAT has been tested for performance as a coaxial thruster. However, due to its limited propellant
capacity, the discharge remains concentrated at a single point and the propellant is not fully utilized. In thisresearch, it is proposed to define a discharge point and change the propellant's shape to rectangular to enable
the loading of more propellant.

目次
図表目次 ................................................................................................................................................ 5
図目次................................................................................................................................................ 5

表目次................................................................................................................................................ 8

第 1章

序論 ...................................................................................................................................... 101.1

超小型衛星革命 ...................................................................................................................... 101.2

超小型衛星の未来................................................................................................................... 101.3

化学推進と非化学推進 ........................................................................................................... 111.4電気推進機 .............................................................................................................................. 13

1.5

超小型衛星専用推進機 ........................................................................................................... 13

1.5.1

研究動向........................................................................................................................... 14

1.5.2

パルスプラズマスラスタ (Pulsed Plasma Thruster, PPT)............................................... 14

1.5.2.1

推進機概要................................................................................................................ 14

1.5.2.2

動作原理 ................................................................................................................... 15

1.5.3
1.6

真空アーク推進機 (Vacuum Arc Thruster, VAT) ........................................................... 16

沿面アーク推進機 (Surface Arc Thruster, SAT)..................................................................... 17

1.6.1

推進機概要 ....................................................................................................................... 171.6.2

推力発生原理 ................................................................................................................... 17

1.6.3

使用推進剤 ....................................................................................................................... 18

1.7

研究室の先行研究................................................................................................................... 211.7.1

電源回路(コンデンサと定電流回路) ............................................................................. 21

1.7.2

同軸型 SAT ...................................................................................................................... 25

1.8

研究目的と研究目標 ............................................................................................................... 27

第 2章

研究原理 .............................................................................................................................. 28

2.1

電気推進機の評価方法 ........................................................................................................... 28

2.2

実験機器 .................................................................................................................................. 28

2.2.1

真空チャンバー ............................................................................................................... 282.2.2

電源装置........................................................................................................................... 30

2.2.3

測定装置........................................................................................................................... 31

2.3

2.2.3.1

クランプオンセンサ・カレントモニタ .................................................................. 31

2.2.3.2

電離真空計................................................................................................................ 32

2.2.3.3

オシロスコープ ........................................................................................................ 33

2.2.3.4

分析天秤 ................................................................................................................... 35

イグナイタ (高圧着火装置) .................................................................................................. 35

第 3章

電気二重層コンデンサ(Electric Double Layer Capacitor)の使用検討............................... 37

3.1

代替コンデンサの検討 ........................................................................................................... 37

3.2

電気二重層コンデンサ(Electric Double Layer Capacitor, ELDC).......................................... 37

3.3

KYOCERA AVX Components 社の電気二重層コンデンサ................................................... 37

3.3.1

単体コンデンサ短絡放電試験 ........................................................................................ 38

3.3.2

使用コンデンサの決定.................................................................................................... 40

3.4回路シミュレーション ........................................................................................................... 41

3.5

コンデンサバンクの作成 ....................................................................................................... 43

3.6

電気二重層コンデンサバンク充放電試験 ............................................................................ 44

3.6.1

充電時間計測 ................................................................................................................... 443.6.2

短絡放電試験 ................................................................................................................... 46

3.7SAT 作動試験 .......................................................................................................................... 47

3.7.1

SAT 噴射確認試験 ........................................................................................................... 47

3.7.2

実験手法........................................................................................................................... 49

3.7.2.1

真空チャンバー圧力測定実験 ................................................................................. 49

3.7.2.2

インパルスビット測定実験 ..................................................................................... 51

3.7.3

3.8

実験結果........................................................................................................................... 54

3.7.3.1

真空チャンバー圧力測定実験 ................................................................................. 54

3.7.3.2

インパルスビット測定実験 ..................................................................................... 55

3.7.3.3

作動試験後の SAT .................................................................................................... 56

第 3 章における考察 ............................................................................................................... 57

3.8.1

選定した電気二重層コンデンサ .................................................................................... 57

3.8.2

電気二重層コンデンサバンク充電時間 ......................................................................... 58

3.8.3

SAT 噴射試験................................................................................................................... 58

3.8.4

真空チャンバー圧力変化 ................................................................................................ 59

3.8.5

インパルスビット ........................................................................................................... 59

3.8.6

作動試験後の SAT ........................................................................................................... 60

第 4章

矩形型 SAT の性能評価 ...................................................................................................... 61

4.1

推進機形状 .............................................................................................................................. 61

4.2

矩形型推進剤 .......................................................................................................................... 62

4.3

矩形型 SAT イメージ図.......................................................................................................... 63

4.4

矩形型 SAT 試作機 ................................................................................................................. 63

4.5

矩形型 SAT 作動試験.............................................................................................................. 65

4.5.1

実験手法........................................................................................................................... 66

4.5.1.1

真空チャンバー圧力測定実験 ................................................................................. 66

4.5.1.2

インパルスビット測定実験 ..................................................................................... 66

4.5.1.3

推進剤流量測定実験 ................................................................................................ 66

4.5.2

実験結果........................................................................................................................... 67

4.5.2.1

アーク電圧................................................................................................................ 67

4.5.2.2

アーク電流................................................................................................................ 68

4.5.2.3

放電時間 ................................................................................................................... 69

4.5.2.4

アーク抵抗................................................................................................................ 70

4.5.2.5

真空チャンバー圧力測定実験 ................................................................................. 71

4.5.2.6

インパルスビット測定実験 ..................................................................................... 72

4.5.2.7

推進剤流量測定実験 ................................................................................................ 74

4.5.2.8推進性能の算出 ........................................................................................................ 744.5.3

作動試験後の矩形型 SAT ............................................................................................... 75

4.5.4

使用電極の検討 ............................................................................................................... 77

4.6

実用的な矩形型 SAT 試作機 .................................................................................................. 79

4.6.1

4.7

実験結果........................................................................................................................... 80

4.6.1.1

アーク電圧................................................................................................................ 80

4.6.1.2

アーク電流................................................................................................................ 81

4.6.1.3

放電時間 ................................................................................................................... 82

4.6.1.4

アーク抵抗................................................................................................................ 83

4.6.1.5

インパルスビット測定実験 ..................................................................................... 84

4.6.1.6

推進剤流量測定実験 ................................................................................................ 86

4.6.1.7

推進性能の算出 ........................................................................................................ 86

第 4 章における考察 ............................................................................................................... 89

4.7.1矩形型 SAT 試作機 .......................................................................................................... 89

4.7.1.1

アーク電圧................................................................................................................ 90

4.7.1.2

アーク電流................................................................................................................ 90

4.7.1.3

放電時間 ................................................................................................................... 90

4.7.1.4

アーク抵抗................................................................................................................ 91

4.7.1.5

真空チャンバー圧力変化......................................................................................... 91

4.7.1.6

インパルスビット .................................................................................................... 91

4.7.1.7

推進剤流量................................................................................................................ 92

4.7.1.8

比推力 ....................................................................................................................... 92

4.7.1.9

作動試験後の矩形型 SAT......................................................................................... 93

4.7.1.10

使用電極の検討 ........................................................................................................ 93

4.7.2

実用的な矩形型 SAT 試作機 ........................................................................................... 93

4.7.2.1

アーク電圧................................................................................................................ 93

4.7.2.2

アーク電流................................................................................................................ 94

4.7.2.3

放電時間 ................................................................................................................... 94

4.7.2.4

アーク抵抗................................................................................................................ 94

4.7.2.5

インパルスビット .................................................................................................... 95

4.7.2.6

推進剤流量................................................................................................................ 95

4.7.2.7

推進性能 ................................................................................................................... 95

第 5章

結論 ...................................................................................................................................... 96

第 6章

今後の課題 .......................................................................................................................... 97

参考文献 .............................................................................................................................................. 98
謝辞............................................................................................................................................ 101

全文をご希望の方は cho@ele.kyutech.ac.jp までご連絡ください。