Copper Loss Minimization Control for the Main Machine in Two-Stage Starter-Generator under Wide Speed Range and Variable Load Conditions

Due to its high voltage and large current operating characteristics, the copper loss of the main machine accounts for a significant proportion of the overall losses in the aviation two-stage high-voltage direct current (HVDC) starter-generator. This feature not only affects the operational efficiency of the system, but also poses a serious challenge to the performance and reliability of the aircraft. To address this issue, this article conducted an in-depth study on the control strategy for minimizing the copper loss of the main machine under the wide speed range and variable load conditions. This control method can quickly determine the reference values of the stator and the rotor current which can minimize the copper loss of the main machine based on the speed and load condition in real time. On this basis, control measures are used to ensure that the starter-generator can operate stably under the optimal conditions. In order to verify the effectiveness of the proposed control method, detailed simulation was conducted in this article, and the results show that compared with traditional id=0 control and MTPA control, the proposed copper loss minimization control method can reduce the copper loss of the main machine under different speed and load conditions, and thus improve the overall operating efficiency of the system.