A Study on the Influence of Stepper Motor Drive Current on SADA Rate Stability

This paper focuses on the effect of stepper motor drive current on the rate stability of Solar Array Drive Assembly (SADA), in order to find a low cost, high performance drive strategy. Based on the mathematical model of stepper motor, the factors affecting torque fluctuation are pointed out. Then to reduce torque fluctuation, different drive current strategies are analyzed and compared. The paper gives the rate stability of SADA under conditions of sinusoidal subdivision current, sinusoidal harmonic compensation current and trapezoidal wave current by experiments. Finally, the paper gives the characteristics of different drive current strategies and their suitable application scenarios. The experiments prove that the sinusoidal subdivision drive strategy works efficiently with simple hardware, and the 4th harmonic compensation to sinusoidal current can further improve the rate stability by 13 %. It is of reference value to the design of SADA stepper motor drive strategies in engineering practice.