Realization and application of continuous adjustment method for ion thruster thrust

To make the ion thruster thrust can be continuously adjusted to the set thrust value and meet the adjustment accuracy, it is necessary to study the ion thruster thrust adjustment method. The traditional thrust adjustment method has narrow thrust adjustment range and single adjustment point, which can't meet the requirements of continuous thrust adjustment. Based on the incremental PID closed-loop control algorithm, the control principle of the algorithm was analyzed, and the PID parameters were set through experiments to get the calculation method of thrust closed-loop control. The algorithm is implemented by software to adjust the output of ion thrusters, the results show that the proportional thrust control accuracy of the ion thruster reaches 0.45%, the minimum thrust control accuracy is 99.2% in the stationary section, and the thrust closed-loop control accuracy is ±0.1 mN. The algorithm can quickly control the ion thruster and make its thrust value reach the target value. Moreover, the ion thruster has continuous adjustable thrust, wide adjustment range and stable thrust output, which can be well applied to the propulsion system of ultra-low orbit Earth observation satellite.