Hundred years ago, Constantinzine Zionkovsky (Soviet Union (Soviet UnionScientists, respected as the "Father of Aerospace") to put forward the idea of electricity.In November 2022, the construction of the first phase of the Chinese manned space station was completed. In addition to the routine chemical promotion system at the end of the core cabin of the space station, it was also equipped with the Hall Electric Promotion System, which marked the first time that human beings applied for electricity in the field of manned spaceflight fieldsystem.
Hol thrustrs with iliac and signs (all are inert gas) ignition
(Figure source: "Knowledge is Power" magazine)
In space
"掂 掂 两"
Traveling in space, there are also two options
The spacecraft travels in space, and will gradually deviate from the established track under the effect of weak resistance and gravity of the earth, the moon, the sun, and the sun.The changes in track and attitude require the space to promote the system to provide the corresponding thrust.Unlike engines that need to mix air on aircraft, cars, and ships. The space promotion system only needs to use its own pushing agent to convert different forms of energy into kinetic energy.
Double Ring Embedlas Hol Pluster at the ignition
(Figure source:" Knowledge is Power "magazine)At present, the spatial advancement system technology adopted by spacecraft is mainly divided into two categories: chemical advancement and electricity advancement.Chemical advancement requires a chemical reaction in the combustion room to produce high temperature and high -pressure gas. Spray backwards and generate thrust. We often see the rocket launch scene on TV.It is the phenomenon generated after igniting the pushing agent; electrical propulsion uses electrical energy to heated or ionize the pushing agent (or the product after the promotion agent burns), which accelerates and ejaculates backwards to generate thrust.
The core cabin of the space station Hall Electric Pushing System formed a schematic diagram
"Power" magazine)
Light weight loss
Quality flow, refers to the flow of the unit timeThe amount of fluid quality of one horizontal section.It can be concluded from the corresponding formula: The quality flow of the thrust = the promotion agent × the speed of the spray of the pushing agent.Therefore, when the thrust is certain, the faster the promotion agent is sprayed with, the smaller the quality flow, and the smaller the quality flow, the slower the pushing agent consumption.
The spacecraft will carry a large number of pushing agents during launch, even far beyond the quality of its core system. At the moment when the "space refueling" technology cannot be widely used, the reserves of the pushing agent can beIt is directly related to the service life of most aerospaces.The pushing agent of electricity is usually higher than chemical advancement, just like cars can "have lower fuel consumption per 100 kilometers". Faced with the same task goal, electricity advancement can consume less advanced agents.
例如，1颗质量5吨的地球同步轨道卫星，将其化学推进换成电推进，有效载荷（直接实现航天器特定任务的仪器、设备、人员、In the case of testing biology and test parts), the quality of carrying propelled agents can be reduced by up to 2.5 to 3 tons; when the total quality is unchanged, the effective load can double and perform more tasks.
Among the many electrical propulsion technologies, because of its excellent comprehensive performance, the Hall Electric Promotion System has become the most widely used electrical advancement technology at present and the largest number of thrust applications.
In particle collision
and Hall effect "Hand Hand"
Hall effect is an electromagnetic effect discovered by American physicist A. H. Hall in 1879, that is, when the current passes the magnetic field vertically in the magnetic field, the movement of the charged particles will be in the magnetic field due to strength in the magnetic field.The role (this force is simply referred to as Lorentz) and bias it aside. Therefore, the difference in potential is the voltage, and the direction of the force of the charged particles can be judged by the left hand.
(source: "Knowledge is Power" magazine)
Hall Electric Promotion SystemThe core of the Hall thrust device, the full name "Hall Effect Pitter", is mainly composed of most of the Hall accelerator and hollow cathode.
Hall accelerator
The main structures such as discharge chamber, internal and external magnetic coils, and anode.The discharge room is generally a circular space, which can provide channels for the flow, ionization and acceleration of the promotion agent.The magnetic coil is combined in the form of "large circle, small circle, outer circle and inner circle", and form a strong magnetic field distributed in the direction of the channel radius at the channel radius of the discharge chamber.The anode is also a ring -shaped, which can produce axial electric field (a special substance that exists in the space around the charging or change magnetic field, which can be opposed to the charge in which the charge is performed).Can evenly allocate the pushing agent.
(Figure source: "Knowledge is Power" magazine)
The promoter used by the anode useIt is some neutral particle flow (because the types of advancement agents are different, these neutral particles may be atoms or molecules. For the convenience of narratives, atoms are used as an example), and they are generally gaseous when they are transported to the thrust device.
Hollow Catholic
At the same time, it is responsible for igniting and neutralization, which is like a heart.When starting, the hollow cathode began to launch electrons outward, and some electrons were attracted by the anode of positive electricity in the Hall accelerator, flying to the discharge room.However, they usually "grab" the strong magnetic field at the exit of the discharge chamber before they flew to the anode, because they intersect vertically with the magnetic field and are affected by Lorentz."Rotating circles", this is Hall drift.A large number of electrons drift in the channel to form Hall current.
The working principle diagram of the Hall thrust device
(Figure source: "Knowledge is Power"Magazine)
Of course, these electrons will not stay at the exit of the discharge room, and their drift will be interrupted by impact atoms, wall surfaces, etc., Form the current circuit between the hollow cathode to anode.
"side shoulders" with plasma
The electronic "circle" while the anode is sprayed outward outwardOut of the atom, these atoms hit electrons with drifting motion and were ionized (atomic outer electrons were bonded from ion nucleus under the collision, becoming free electrons, and the atom itself became a ion with a positive charge).The axial electric field applies to these ions to accelerate, ejaculate, and generate thrust.Among the electronics emitted by the hollow cathode, the electrons that have not been attracted by the anode will "hit" the sprayed ions, and the two are "neutralized" into a neutral atom.
In this way, the Hall thrust device spray ions, electronics, and atoms at the same time, forming a plasma (composed of a large number of particles, which keeps electrical neutral in the material state) Yu Liu.Because its ionization, acceleration, neutralization, etc. are stable in macro, it is also called "steady -state plasma thrust".
Maybe everyone will ask, why do the ions generated by ionization spray out instead of being "caught" like electrons?This is because the quality of ions is much greater than that of electrons (such as the quality of ions is about 240,000 times that of its electronic quality).The magnetic field in the accelerator is carefully designed, with the appropriate strength and shape. The strongest place is placed in the exit part of the discharge chamber, which is mainly used to restrain electronics, and it is almost missing to ions. ThereforeEssence
Promoting the behemoth
"Small bodies"
Theoretically, the Hall thruster can generate very large thrust, but the current power can be provided with limited electrical power, so their thrust is limited to the slot.Niuweig.However, the astronauts resistance in space is extremely small, and the sluggish thrust can also help the spacecraft to complete the tasks such as large -scale rail transfer.
Hall thrust device physical map and its ground ignition status
(Picture source: "Knowledge is Power" magazine)
China Space Station runs on a high -altitude track of about 400 kilometers from the ground, the flight speed is as high as 7.7 kilometers/Second.Under the influence of various forces, the speed of the space station will continue to slow down, and the height of the track will continue to decline. Therefore, the space station needs to continuously compensate the atmospheric resistance through its own power to maintain the normal flight speed and rail height.
Hall Electric Pushing System Promotional Promotional Consumption, long work life, and strong ability, can "have long water flow" with the power of the slightest.After comprehensive consideration, scientific researchers decided to configure 4 Hall thrustrs for the core compartment of the space station. They were two or two pairs, and were symmetrically installed on both sides of the core cabin. The thrust was 80 mm bulls.
On April 29, 2021, the core cabin followed the Long March 5 and the Rocket Rockets was launched on track.The system has pioneered a number of international technologies. The Hall thrust device adopts the installation method of plugging. In addition to the two small cylinders carried with the cabin, the installation interface of 2 air bottles is reserved.It is necessary to maintain, upgrade, and supplement the pushing doses of gas cylinders.
In recent years, the scientific research and application innovation of the Hall Electric Promotion System at home and abroad has continued to increase, and the types of pushing agents have increased.In the discharge chamber, it has a larger power, larger thrust and wider adjustment on the premise of small size.Typical aerospace missions such as manned moon detection, rail service, space resources mining and utilization, and asteroid defense all put forward clear demand for the Hall Electric Promotional System. It is continuously improving and promoting us to better explore the vast universe.
Written text | Hang Guanrong, Jin Guangming
Editor in charge | Niu Yi, Duan Yangyang
Operation Edit | Duan Yangyang
Quality Audit | Industry Lei
❖ Article Source: "Knowledge is Power" magazine
"Pirellial Warriors" Hall Electric Promotion System of Promoting Space Station ">
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