Patent Application
20230257135
This application claims priority to Chinese Patent Application No. 202010298568.1 filed on Apr. 16, 2020 and entitled “Micro-cathode arc propulsion system”, the entire contents of which are incorporated herein by reference.
The present disclosure relates to the technical field of micro propulsion for satellites, and in particular relates to a micro-cathode arc propulsion system.
The micro-cathode arc thruster has become an ideal electric propulsion type for micro-nano satellites due to its advantages of micropowering, high efficiency, high specific impulse, adjustable wide range and low cost, and can be used in missions such as orbit keeping and formation flight of micro-nano satellites. The traditional micro-cathode arc propulsion system circuit is as shown in
An objective of the present disclosure is to provide a micro-cathode arc propulsion system capable of improving the stability of the operation of a thruster as well as reducing additional power consumption of a circuit.
To achieve the objective above, the present disclosure provides the following technical solutions:
A micro-cathode arc propulsion system comprises:
a power supply, a resistor, a capacitor, an IGBT module and a micro-cathode arc thruster.
A positive electrode of the power supply is connected to one terminal of the resistor, the other terminal of the resistor is connected to one terminal of the IGBT module and one terminal of the capacitor, respectively, and the other terminal of the IGBT module is connected to an anode of the micro-cathode arc thruster. A cathode of the micro-cathode arc thruster and the other terminal of the capacitor are connected to a negative electrode of the power supply.
Alternatively, the IGBT module specifically comprises:
a pulse generator and an IGBT.
The pulse generator is connected to a gate of the IGBT, a drain of the IGBT is connected to the other terminal of the resistor, and a source of the IGBT is connected to the anode of the micro-cathode arc thruster.
Alternatively, the power supply is a 500 V DC power supply.
Alternatively, the resistor has a resistance of 50 kΩ.
Alternatively, the capacitor has a capacitance of 0.5 μf.
Alternatively, the power supply is a pulse power supply.
Alternatively, an insulating layer of the micro-cathode arc thruster is arranged between the cathode and the anode of the micro-cathode arc thruster.
Alternatively, the micro-cathode arc propulsion system further comprises:
a permanent magnet.
The permanent magnet is arranged on the cathode of the micro-cathode arc thruster.
Alternatively, the cathode of the micro-cathode arc thruster, the other terminal of the capacitor and the negative electrode of the power supply are all grounded.
According to specific embodiments of the present disclosure, the present disclosure has the following technical effects:
A micro-cathode arc propulsion system is provided. By replacing an inductive circuit in a traditional micro-cathode arc propulsion system with a capacitor circuit, the stability of the operation of a micro-cathode arc thruster can be improved due to the stable discharging mode of the capacitor, and as the internal resistance of the capacitor is small during operation, the additional power consumption of the circuit is reduced, and the efficiency of the system is improved.
In addition, as a pulse power supply is used to power in a pulse manner, the average power inputted into the micro-cathode arc thruster is greatly reduced.
To describe the technical solutions in the embodiments of the present disclosure or in the prior art more clearly, the following briefly introduces the accompanying drawings required for describing the embodiments. Apparently, the accompanying drawings in the following description show merely some embodiments of the present disclosure, and a person of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.
The following clearly and completely describes the technical solutions in the embodiments of the present disclosure with reference to the accompanying drawings in the embodiments of the present disclosure. Apparently, the described embodiments are merely a part rather than all of the embodiments of the present disclosure. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present disclosure without creative efforts shall fall within the protection scope of the present disclosure.
An objective of the present disclosure is to provide a micro-cathode arc propulsion system capable of improving the operating stability of a thruster as well as reducing additional power consumption of a circuit.
To make the objects, features and advantages of the present disclosure more apparent, the present disclosure will be described in further detail below with reference to the accompanying drawings and specific embodiments.
During implementation of the present disclosure, a power processing unit (PPU) comprises a resistor 12, a capacitor 13, and an IGBT module 14. The voltage released by the PPU is directly applied between the two polar plates of the micro-cathode arc thruster 15, and the voltage value may affect the state of the arc and thus affect the propulsion performance of the thruster. The capacitance may determine the maximum electric quantity in single discharging of the PPU, and the increase of the capacitance is helpful for boosting an output voltage of the PPU within a certain range. The switching frequency of the IGBT 402 may determine whether the PPU can reach the maximum discharging state and the stable and continuous output of power by the PPU.
To achieve the purpose of the stable operation of the micro-cathode arc thruster 15, it should be guaranteed that the PPU can acquire enough electric energy. In a case that parameters for the power supply are fixed, it is necessary to design the capacitance value, the charging time and a circuit resistance value, and the charging time of the capacitor 13 may be calculated by means of an empirical formula:
τ=RC
Where C is a capacitance value, R is a current-limiting charging resistance; τ is a charging/discharging time constant.
In accordance with the present disclosure, the micro-cathode arc propulsion system 10 is powered by using 500 V, in order to reduce the power inputted into the thruster as much as possible, the PPU should operate in a high-voltage and low-current state; in order to control the current to reduce, the resistance is chosen to be 50 kΩ. When the capacitance is 0.5 μf, the charging time constant of the capacitor 13 is 0.025, and when the time is greater than 0.125 s, it may be considered that the capacitor 13 has been fully charged. The equivalent resistance at the breakdown moment of the micro-cathode arc thruster 15 is generally in the order of several ohms to tens of ohms, which is related to design parameters of the thruster. When the equivalent resistance is 10 ohms, the discharging time constant is 5×10−6 s, and it can be considered that discharging of the capacitor 13 has been completed at 25×10−6 s under an ideal condition. Because the charging time (0.125 s) is much greater than the discharging time (25×10−6 s), the IGBT 402 may operate at the maximum switching frequency of 8 Hz, and based on such parameters, the thruster may operate work stably and efficiently in a low-power state.
In accordance with the present disclosure, the PPU circuit is changed, a 500 V DC power supply is used to supply power, and a traditional discharging mode of an inductor is replaced with a discharging mode of a capacitor which is more stable in discharging, thereby stabilizing the operation of the thruster. Due to the charging/discharging characteristics of the capacitor, the input power supply operates in a pulse manner so as to reduce the average power inputted into the thruster. As the internal resistance of the capacitor is small during operation, the additional power consumption in the PPU circuit is reduced. The voltage with the same amplitude is used to discharge the micro-cathode arc thruster 15, such that the discharging repeatability is improved, and the service life of the thruster is prolonged. In accordance with the present disclosure, the problem of power consumption of the PPU circuit in the micro-cathode arc propulsion system 10 is solved. During the discharging of the capacitor, the input power supply does not input power into the PPU circuit, and the input power supply operates in a pulse manner so as to achieve the purpose of reducing the power inputted into the thruster.
Several examples are used for illustration of the principles and implementation methods of the present disclosure. The description of the embodiments is merely used to help illustrate the method and its core principles of the present disclosure. In addition, a person of ordinary skill in the art can make various modifications in terms of specific embodiments and scope of application in accordance with the teachings of the present disclosure. In conclusion, the content of this specification shall not be construed as a limitation to the present disclosure.
The above embodiments are provided solely for the purpose of describing the present disclosure and are not intended to limit the scope of the present disclosure. The scope of the present disclosure is defined by the appended claims. Various equivalents and modifications made without departing from the spirit and principles of the present disclosure are intended to be within the scope of the present disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202010298568.1 | Apr 2020 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2020/115008 | 9/14/2020 | WO |
