China makes major breakthrough in space propulsion technology

[beijingwalker]

China makes major breakthrough in space propulsion technology
Technology 22:58, 18-Jan-2020

The 20-kW Hall thruster in operation at a laboratory of the China Aerospace Science and Technology Corporation (CASC). /Photo via CASC

China has made a major breakthrough in the development of the Hall-effect thruster (HET), an important space propulsion technology.

Researchers from the China Aerospace Science and Technology Corporation (CASC) have developed the country's first HET with an input power of 20 kilowatts that can produce a thrust of one newton, marking a leap for China's HETs from millinewton level to newton level.

The applications of HETs include control of the orientation and position of orbiting satellites and use as a main propulsion engine for medium-size robotic space vehicles.

During a test, the thruster showed stable operation, with a specific impulse of 3068 seconds and working efficiency above 70 percent, reaching international advanced level.

Such a high-power HET with features of strong thrust, long working life and high reliability will be able to provide highly efficient impetus for the positioning, orbital maneuvering and motion control of large GEO (geostational orbit) satellites, deep space probes and space shuttle vehicles.

https://news.cgtn.com/news/2020-01-...e-propulsion-technology-NmsflfbgNG/index.html

 

[Dante80]

Good news, this would allow China to develop and field all-electric sats without needing to depend on foreign suppliers.

 

[Viet]

do I read 1 N?

How can it be a major breakthrough for the mankind?

1 N can only lift a mass of 100 gram.

chinese scientists need the energy of several server racks, 20 kW, to move an 0.1 kg object?

OK congrats.

 

[Dante80]

1 N?

How can it be a major breakthrough for the mankind?

1 N can only lift a mass of 100 gram.

chinese scientists need the energy of several server racks, 20 kW, to move an 0.1 kg object?

OK congrats.

Hall effect thrusters (and most electric propulsion systems for that matter) provide small amounts of thrust for extremely long amounts of time at terrific efficiency. It is exactly what you need for an orbit-raising or station keeping propulsion system, and the reason that are routinely deployed in satellites since the early 70's.

The way they operate is using electricity to ionize and propel an inert gas like xenon or argon. While this results in a big power consumption for the system itself, the amount of fuel needed is infinitesimal when compared to conventional liquid propulsion. Moreover, the Isp (fuel efficiency) of the system is an order of magnitude larger, meaning that an all electric GEO satellite can shed 2 or more tons of valuable weight by simply switching from liquid to electric propulsion.

Hope that helps.

 

[Viet]

Hall effect thrusters (and most electric propulsion thrusters for that matter) provide small amounts of thrust for long amounts of time at terrific efficiency. It is exactly what you need for an orbit-raising or station keeping propulsion system, and the reason that are routinely deployed in satellites since the early 70's.

Ok but how can you sustain the power input for a long period in space if you spend 20 kilowatts for every one newton? The input energy must come from somewhere?

 

[Dante80]

Ok but how can you sustain the power input for a long period in space if you spend 20 kilowatts for every one newton? The input energy must come from somewhere?

In satellites where the system is used, the power comes from their solar panels.

The application btw works very well for interplanetary probes too. In that case, power is provided from solar panels or RTGs.

See Dawn, Deep Space 1 or Hayabusa as some examples.

 

[Viet]

In satellites where the system is used, the power comes from their solar panels.

The application btw works very well for interplanetary probes too. In that case, power is provided from solar panels or RTGs.

See Dawn as an example.

Ok let’s do the Math

Take Gaofen 1, the sat weights some 1080 kg in total.

that means you need an energy input of:

20 kW per 0.1 kg x 1080 kg = 216000 kW or 216 MW or equal a small power plant

how many solar panels are necessary?

 

[Dante80]

Ok let’s do the Math

Take Gaofen 1, the sat weights some 1080 kg in total.

that means you need an energy input of:

20 kW per 0.1 kg x 1080 kg = 216000 kW or 216 MW

how many solar panels are necessary?

I could do the math for you, but I think it would be even easier/faster to just understand that there is a valid reason for both planetary probes and satellites using electric thrusters.
If there wasn't one, they wouldn't really exist. Would they?

For reference, Vinasat-1 and Vinasat-2, the national satellites of Vietnam use ion thrusters in conjunction with a Leros hydrazine system.

 

[Viet]

I could do the math for you, but I think it would be even easier/faster to just understand that there is a valid reason for both planetary probes and satellites using electric thrusters.
If there wasn't one, they wouldn't really exist. Would they?

For reference, Vinasat-1 and Vinasat-2, the national satellites of Vietnam use ion thrusters in conjunction with a Leros hydrazine system.

No problem I do the math for you.
This water solar power plant below in Vietnam generates 47 MW. To move Gaofen sat I need 4 or 5 such large solar plants in space.
Unrealistic don’t you think so?

 

[Dante80]

No problem I do the math for you.
This water solar power plant below in Vietnam generates 47 MW. To move Gaofen sat I need 5 such large solar plants in space.
Unrealistic don’t you think so?

Extremely unrealistic. I think you might have to work on your math a little, right?

 

[Viet]

Extremely unrealistic. I think you might have to work on your math a little, right?

why? My math is correct.

I don’t say this Hall stuff is for idiots. But if chinese scientists can reduce power consumption from 20kW to let’s say 0.1kW then we can celebrate this feat as breakthrough for the human race (in case China share the technology to the non-chinese human race).

 

[Dante80]

why? My math is correct.

Your math is incorrect (to be more specific, your math is irrelevant as regards to how a hall thruster operates). And the power consumption of the described system is actually pretty impressive for a hall thruster (most commercially available systems of this exact type usually need around 22kW for said output). Granted, this was in a laboratory setting, efficiency should be expected to go down a little on a commercial model.

Moreover, I think you are exaggerating a little. CASC has announced a TRL breakthrough in indigenous HET propulsion. They never said that "this is a breakthrough for the human race". As I already said, HETs have been around since the 70's. And in research/laboratory settings, HETs of up to 100kW class have been tested, so far.

 

[Pandora]

why? My math is correct.

I don’t say this Hall stuff is for idiots. But if chinese scientists can reduce power consumption from 20kW to let’s say 0.1kW then we can celebrate this feat as breakthrough for the human race (in case China share the technology to the non-chinese human race).

You are ignoring the fact that these thrusters are not meant for long range maneuverability. In space there is no drag so no much power is required to move a satellite or probe. At most it is used for repositioning or altitude adjustment.

 

[Danish Moazzam]

Second the above statement. You are ignoring the fact that it is Zero Friction environment. so even that minor force will be sufficient to correct the orientation or re position the satellite

 

[PeacefulWar]

why? My math is correct.

I don’t say this Hall stuff is for idiots. But if chinese scientists can reduce power consumption from 20kW to let’s say 0.1kW then we can celebrate this feat as breakthrough for the human race (in case China share the technology to the non-chinese human race).

F=MS
1 Newton can accelerate 1 KG to speed 1m/s.
Rest you can do the speed.

Your math is so wrong in many ways, I don't even know where to start correcting it.