Research On Excitation Convertor For Hybrid Excitation Synchronous Generator

Rotating rectifier brushless synchronous motor is widely used in the Aircraft Power System due to its adjustable power factor and high efficiency. So it is of great significance to research profoundly about it. This paper researches about the digital excitation controller based on the hybrid excitation brushless synchronous motor designed by our research team.Firstly, this thesis describes the development of the Aircraft Power System, as well as the present situation of aero-electric machines, and then gives some introduction about the generator studied in this paper. Secondly, research has been conducted by the means of theoretical analysis and simulation to reveal the relationship between the single-phase ac excitation and the generator's excitation voltage, by which the best single-phase ac excitation control law is obtained. Feasibility has been proved by experiment on generator. Finally the paper describes the design methods of hardware and software used in the excitation controller based on TMS320LF2407A,and presents the hardware schematic diagram and the software flowchart. The hardware design contains the circuit of the least system module of DSP, the sampling and adjusting circuit of ac analog signal, the frequency measurement circuit, the drive circuit, the protection circuit and so on. The software design contains the system initialization, the frequency calculation module, the data acquisition and process module, the control algorithm design , the fault detection and protection unit, which are realized by C language programme. The test result indicates that the excitation controller based on TMS320LF2407A has characters of simple hardware structure, high reliability, easy maintains, high. performance-price ratio, etc.The work of this paper serves as the reference for the further research of rotating rectifier brushless synchronous motor, laying the foundation for the engineering application of the motor.