JPH10184530A - Dc arc thruster - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out restart automatically in the case where arc discharge of a dc arc thruster by connecting a condensed element to between an anode element and a cathode element of an automatically starting power supply device which is connected in parallel to a mainly discharging power supply device. SOLUTION: An automatically starting power supply device 18 as large voltage low current power supply is connected in parallel to a mainly discharging power supply device 13 for supplying main discharging current 17 for generating arc discharge 16 between an anode 6 and a cathode 8 through an anode side connection 14 and a cathode side connection 15 of a power feeding cable 12, through a confluent anode side connection 28 and a branch cathode side connection 29. A condensed element 21 such as a condenser is connected to between an anode element 19 and a cathode element 20 of an automatically starting power supply device 18. In the case where arc discharge 16 is eliminated, the condensed element 21 is charged, the same high voltage as that of the automatically starting power supplying device 18 is applied between the anode 6 and the cathode 8, and arc discharge 16 is restored between the anode 6 and the cathode 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct current arc thruster, and more particularly, to a direct current arc thruster capable of automatically restarting when an arc discharge has disappeared.

[0002]

2. Description of the Related Art DC arc thrusters are used to control the orbit and attitude of artificial satellites and the like.

As shown in FIG. 3, the DC arc thruster locks a nozzle 5 for injecting a propellant 4 onto one end of the arc thruster main body 3 attached to the artificial satellite main body 1 via a bracket 2. By this, the anode 6 is constituted by the arc thruster main body 3 and the nozzle 5, and the tip of the anode 6 is located at the inner axial position of the arc thruster main body 3.
The cathode rod 8 is arranged so as to be located in the expansion space 7 formed therein, and the arc thruster main body 3 as the anode 6 and the cathode rod 8 are arranged.
And a propellant supply passage 10 for supplying the propellant 4 from a supply source (not shown) to the expansion space 7 inside the arc thruster main body 3. A power supply cable 12 for supplying power from the main discharge power supply 13 to the anode 6 and the cathode rod 8 is connected to the other end via the connector 11.

According to such a configuration, the main discharge power supply device 1
3 through the power supply cable 12 and the connector 11 to supply power to the anode 6 and the cathode rod 8, thereby generating an arc discharge between the nozzle 5 and the tip of the cathode rod 8. To supply the propellant 4 to the expansion space 7 through the propellant supply passage 10, thereby expanding the propellant 4 in the expansion space 7 with the energy of the arc discharge,
By injecting the propellant 4 expanded in this way from the nozzle 5, the orbit control and attitude control of an artificial satellite or the like can be efficiently performed with a small amount of propellant 4.

[0005]

However, the above-mentioned conventional DC arc thruster has the following problems.

That is, the DC arc thruster is started and stopped by a remote control command from the ground. However, since arc discharge is very delicate,
When the supply amount of the propellant 4 fluctuates due to bubbles mixed into a propellant supply system such as a supply source or the propellant supply path 10 (not shown), the arc discharge may be extinguished (extinguished). .

When the arc discharge has disappeared, it is necessary to detect the disappearance of the arc discharge by some means. Further, when it is detected that the arc discharge has disappeared, a command must be sent by remote control from the ground to restart the DC arc thruster, which imposes a heavy burden on the ground operator.

The present invention has been made in view of the above circumstances, and has as its object to provide a DC arc thruster capable of automatically restarting when an arc discharge has disappeared.

[0009]

SUMMARY OF THE INVENTION The present invention provides a main discharge power supply unit 13 for supplying a main discharge current 17 for generating an arc discharge 16 between an anode 6 and a cathode 8 by using a large voltage low current. A DC arc thruster according to claim 1, characterized in that an automatic starting power supply device 18 as a power supply is connected in parallel, and a storage element 21 is connected between an anode terminal 19 and a cathode terminal 20 of the automatic starting power supply device 18. It is.

In this case, the power supply 1 for automatic start
Reference numeral 8 denotes a large-voltage low-current power supply having a voltage of 2 kV and a starting current 26 of about 10 mA, and the power storage element 21 may be a capacitor having a capacity of about 10 μF.

According to the above means, the following effects can be obtained.

While the arc discharge 16 is being generated between the anode 6 and the cathode 8 of the DC arc thruster, the anode terminal of the power supply unit 13 for the main discharge, the anode 6, the portion of the arc discharge 16, the cathode 8, the power supply for the main discharge A main discharge current 17 flows through the cathode terminal of the device 13.

At this time, the anode terminal 19, the anode 6, the arc discharge 16 portion, the cathode 8, and the cathode terminal 20 of the automatic starting power supply 18 and 10 mA at 2 kV are connected.
A starting current 26 of the order will flow. However, the starting current 26 is about 10 mA, and the
Since the current is extremely small compared to the main discharge current 17 of No. 3,
The arc discharge 16 has no influence.

If the arc discharge 16 has disappeared for some reason, the main discharge current 17 of the main discharge power supply 13 stops.

Then, the start-up current 26 of the automatic start-up power supply 18 flows into the electric storage element 21 such as a capacitor connected between the anode terminal 19 and the cathode terminal 20 of the automatic start-up power supply 18, and the capacitor or the like. Is charged.

When the storage element 21 such as a capacitor is charged to a certain extent, a high voltage as high as 2 kV is applied between the anode 6 and the cathode 8 as in the power supply unit 18 for automatic start. The dielectric breakdown between the anode 6 and the cathode 8 is caused by the high voltage of 2 kV of the element 21, and the anode 6
Glow discharge is generated between the anode 6 and the cathode 8, the glow discharge shifts to the arc discharge 16, and the arc discharge 16 is automatically restored between the anode 6 and the cathode 8. After the arc discharge 16 is restored, the main discharge current 17 is supplied again from the main discharge power supply device 13, and the arc discharge 16 is maintained.

The time required for re-ignition of the arc discharge 16 is
Less than one second is very short.

As described above, by providing the power supply unit 18 for automatic start, the DC arc thruster can be automatically restarted without waiting for a command from the ground.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 and FIG. 2 show an embodiment of the present invention.

Since the basic structure of the DC arc thruster is the same as that of FIG. 3, FIG. 3 will be referred to if necessary.

In the present invention, a main discharge current 17 for generating an arc discharge 16 between the anode 6 and the cathode 8 (cathode rod) is supplied via the anode connection 14 and the cathode connection 15 of the power supply cable 12. The power supply device 13 for automatic discharge, which is a large-voltage low-current power supply, is connected in parallel to the power supply device 13 for main discharge through a merging anode side connection 28 and a branch cathode side connection 29.

Then, a power storage element 21 such as a capacitor is connected between the anode terminal 19 and the cathode terminal 20 of the power supply unit 18 for automatic start.

Further, the branch point 2 in the cathode side connection 15
2, a diode 24 for branch rectification and backflow prevention is mounted at a position closer to the cathode terminal 23 side of the power supply device 13 for main discharge, and similarly, a branch point 2 in the branch cathode side connection 29.
A diode 25 for branch rectification and backflow prevention is mounted at a position closer to the cathode terminal 20 side of the power supply device 18 for automatic start than at 2 and closer to a branch point 22 than a connection portion of the storage element 21 such as a capacitor.

The voltage of the arc discharge 16 is about 100
Since the main discharge power supply device 13 has a voltage of 150 V, a power supply having a main discharge current 17 of about 15 A is used.

The voltage of the glow discharge (normal glow discharge and abnormal glow discharge) that needs to be generated before the arc discharge 16 occurs is about 150 to 300 V. A large-voltage low-current power supply having a starting current 26 of about 10 mA at 2 kV is used, and a capacitor having a capacity of about 10 μF is used as the storage element 21.

In the figure, reference numeral 27 denotes an anode terminal of the power supply unit 13 for main discharge.

Next, the operation will be described.

FIG. 3 shows the operation of the DC arc thruster.
Therefore, the description is omitted.

According to the present invention, while the arc discharge 16 is being generated between the anode 6 and the cathode 8 of the DC arc thruster, as shown in FIG. Anode connection 14 of cable 12, anode 6,
A main discharge current 17 of about 15 A at 150 V flows through the arc discharge 16 portion, the cathode 8 (cathode bar), the cathode connection 15 of the power supply cable 12, the cathode terminal 23 of the power supply device 13 for main discharge.

At this time, as shown in FIG. 1, the anode terminal 19 of the power supply unit 18 for automatic start, the merging anode side connection 28, the anode side connection 14 of the power supply cable 12, the anode 6, the arc discharge 1
6 parts, cathode 8 (cathode bar), cathode side connection 15 of power supply cable 12, branch cathode side connection 29, power supply device 1 for automatic startup
8 and a starting current 26 of about 10 mA at 2 kV flows. However, the starting current 26
Is about 10 mA, which is extremely small compared to the main discharge current 17 of the main discharge power supply 13, so that the arc discharge 1
6 has no effect.

If the arc discharge 16 is extinguished for any reason, the main discharge power supply 1
3, the anode terminal 27 of the power supply cable 12
4, anode 6, arc discharge 16 parts, cathode 8 (cathode bar),
The main discharge current 17 flowing through the cathode side connection 15 of the power supply cable 12 and the cathode terminal 23 of the main discharge power supply device 13 stops.

Similarly, the anode terminal 19 of the power supply device 18 for automatic start, the junction anode connection 28, the anode connection 14 of the power supply cable 12, the anode 6, the arc discharge 16 portion, the cathode 8 (cathode rod), and the power supply cable 12 Of the cathode-side connection 15, the branch cathode-side connection 29, and the start-up current 26 flowing through the cathode terminal 20 of the power supply device 18 for automatic start-up.

However, as shown in FIG. 2, the start-up current 26 of the power supply 18 for automatic start-up is controlled by a capacitor connected between the anode terminal 19 and the cathode terminal 20 of the power supply 18 for automatic start-up. Flows into the storage element 21, and the storage element 21 such as a capacitor is charged.

When the storage element 21 such as a capacitor is charged to a certain degree, the same high voltage as 2 kV as that of the power supply unit 18 for automatic activation is applied between the anode 6 and the cathode 8 (cathode bar). Therefore, a voltage as high as 2 kV of the storage element 21 such as a capacitor causes a dielectric breakdown between the anode 6 and the cathode 8 (cathode bar), a glow discharge is generated between the anode 6 and the cathode 8, and the glow discharge is reduced to an arc discharge 16. The arc discharge 16 is automatically restored between the anode 6 and the cathode 8. After the arc discharge 16 is restored, the main discharge current 17 is supplied again from the main discharge power supply device 13, and the arc discharge 16 is maintained.

The time required for re-ignition of the arc discharge 16 is
Less than one second is very short.

Further, the power supply device 18 for automatic start-up can be used not only for re-ignition of the arc discharge 16 but also for the first ignition. If the power supply device 18 for automatic start is used also at the time of the first ignition, the ignition inductor circuit used in the power supply device 13 for main discharge can be reduced. The total weight increase due to the device 18 and the like is also about 200 g, which can be suppressed to a range where there is no support in actual operation.

As described above, by providing the power supply device 18 for automatic start, the DC arc thruster can be automatically restarted without waiting for a command from the ground.

It should be noted that the present invention is not limited to only the above-described embodiment, and it is needless to say that various changes can be made without departing from the spirit of the present invention.

[0040]

As described above, according to the DC arc thruster of the present invention, an excellent effect that the arc discharge can be automatically restarted when the arc discharge has disappeared can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic system diagram of a power supply portion according to an example of an embodiment of the present invention.

FIG. 2 is an operation diagram in the case of a restart of FIG. 1;

FIG. 3 is a schematic overall side sectional view of a conventional example.

[Explanation of symbols]

 Reference Signs List 6 anode 8 cathode 13 power supply device for main discharge 16 arc discharge 17 current for main discharge 18 power supply device for automatic start 19 anode terminal 20 cathode terminal 21 power storage element

Claims (2)

[Claims] A large voltage is applied to a main discharge power supply (13) for supplying a main discharge current (17) for generating an arc discharge (16) between an anode (6) and a cathode (8). A power supply device (18) for automatic start, which is a low-current power supply, is connected in parallel, and a power storage element (21) is connected between an anode terminal (19) and a cathode terminal (20) of the power supply device for automatic start (18). A DC arc thruster characterized in that: 2. A power supply device for automatic startup (18) is a large-voltage low-current power supply having a voltage of 2 kV and a startup current (26) of about 10 mA, and a storage element (21) having a capacity of about 10 μF. The direct current arc thruster according to claim 1, wherein