Design And Research On Starter/Generator Controller For Variable Frequency AC Power System Based On Hybrid Excitation Synchronous Machine

Using the electrical machine to start an aeroengine has been possible due to the development of MEA/AEA which improves the electrical power capacity of an aircraft. Variable-Frequency(VF) AC power system has become the trend of the future aircraft AC power system for its simple structure, easy maintenance, high unit capacity. Besides, it's also easy to form a starter/generator(S/G) system. The novel hybrid excitation synchronous machine(HESM), which has the ability of field regulation, high power density and high effiency, is of great application prospect in aircraft power system. Thus, it is meaningful to do research on its control technology.The operation principle of S/G system based on HESM for aircraft VFAC power system is analyzed. On the basis of discussing the structure and excitation regulation characteristics of the HESM with magnetic shunt rotor, the mathematical equations of HESM in dq0 coordinate system are obtained. A simulation model of S/G system based on HESM is established by using Matlab/Simulink. After that, the effects of excitation current on starting performance and voltage regulation performance are studied.The control strategies of HESM with magnetic shunt rotor for VFAC S/G system are further investigated. Starting torque characteristics of the aeroengine is discussed in detail firstly, and two electrical starting methods for the aeroengine are introduced. Furthermore, the design requirements of integrated S/G are analyzed. The influences of field current on the indunctance of field winding and armature winding are also studied, based on which the influences of field current on starting control strategy of HESM are analyzed. What's more, a coordination control strategy based on field current and armature current is proposed for VFAC S/G system. And simulations show that the output torque of HESM in high speed operation is greatly improved employing the coordination control method.A controller of HESM for VFAC S/G system is designed, based on which the VFAC S/G system test platform is set up. The experimental results show that the starting performance of HESM with magnetic shunt rotor is improved effectively by the excitation current, and the output torque of HESM in high speed operation is enhanced by the proposed coordination control method and HESM with magnetic shunt rotor has a bright future for aircraft S/G system.