From low orbit to high orbit, we need to overcome gravity to do work, so we need a force to do positive work on the object, and the work on the satellite is realized by jet. In the low orbit, if you want to move to the high orbit, you must have external forces to do positive work on it. Doing positive work on it will increase its kinetic energy and speed, so it will start to do centrifugal motion.

However, in the process of centrifugation, it is necessary to overcome gravity to do work, so the speed will become smaller. It is impossible to change a circular orbit from a circular orbit to a high orbit at one time, but it will only become an elliptical orbit. To become a high orbit, you need to change orbit again from apogee, and the running speed will be the lowest at apogee, then change orbit and repeat the process I said above.

From the perspective of energy analysis

Estimation: Assuming the satellite mass is 2 tons, the original orbit radius is 342.8 kilometers, and the current orbit is changed to 349 kilometers. The added value of the gravitational potential energy of the satellite is (assuming that the gravitational acceleration value is constant during the process, the value is10m/s 2), and the converted value of the kinetic energy of the satellite during the process is (gravitational constant g = 6.67×10-1n m 2/kg).

From the above estimation, it can be seen that the increase of gravitational potential energy is much greater than the decrease of kinetic energy in the process of satellite orbit change (from low orbit to high orbit).

Baidu encyclopedia-satellite orbit change