Simulating parameter matching for propulsion system of high altitude airship

The dynamic simulation of the performance of the propulsion system of a high-altitude airship can adjust the parameters of the energy-consuming parts in advance, enhance its efficiency and reduce the weights of a solar cell and lithium battery. We use the MATLAB/Simulink and the PID and PI controls to establish the simulation model of the rotational speed and current double-loop serial control motor by building and integrating the multiple independent functional modules of a rare-earth permanent magnet brushless DC motor. We also use the motion equation of the propeller of the high-altitude airship to establish its dynamic simulation model. Then we integrate all the simulation modules with the matching between the torque of the DC motor and the rotational speed of the propeller. With the integrated simulation modules, we match the parameters of all the parts of the propulsion system. The simulation results, given in Figs. 2 through 6, and their analysis show preliminarily that deceleration ratio of the propulsion system decreases with increasing altitude. Thus we obtain the optimal deceleration ratio of the propulsion system at different altitudes and the dynamic response characteristics of the propulsion system whose propeller has different diameters. We also obtain the optimal rated working point and working area of the propulsion system whose propeller has the diameter of 6.8 meters.