Abstract: Abstract：Aming at the problems of attitude stability and fuel consumption optimization in the process of attitude control using thrusters, a detailed introduction is made on pulsewidth pulsefrequency (PWPF) pulse modulator and pseudo rate modulator (PSR).The attitude control laws designed with PWPF and PSR modulators are simulated and analyzed respectively, and then the advantages and disadvantages of the two modulators are summarized. By using double time constant to reduce fuel consumption, adding a firstorder inertial filter to reduce the influence of noise so as to improve the attitude control stability, an improved pulse modulator is designed. The simulation results show that the proposed modified pulse modulator is fuel economic and with the same attitude accuracy compared to PWPF modulator. Moreover, the modified pulse modulator significantly improves the accuracy of attitude stabilization compared to PSR modulator.  

Key words: Keywords：attitude control thruster, pulse modulator, double time constant, inertial filter