Research On 400Hz High Power Ground Power Units For Airplanes

With the rapid development of Power electronics in our country, that localization Ground Power Unit(GPU) replace Diesel Power Car and Auxiliary Power Unit as the ground power equipment used in domestic airport has been gradually changed into reality, and also was an inevitable trend in the development of low-carbon energy of present domestic society. Based on the digital FPGA and DSP development platform, high power GPU was studied deeply in this paper.At first, several existing topologies and control strategies of high power inverter system were introduced and compared. Combined three-phase inverter topology adopted in this paper was emphatically analyzed. Moreover, stationary coordinate model and synchronous coordinate model of this inverter model was also derived.By improving the traditional PI controller, a new uniform control strategy of three-phase inverter was proposed, which was based on the separation control of fundamental and harmonic in synchronous coordinate. The structure of the new PI controller was analyzed in detail, whose simulation module in MATLAB was established accordingly. Compared with the traditional PI controller, the simulation results indicates that, the separation controller has relatively better steady-state and dynamic control performance even when the inverter system is connected with nonlinear load. Besides, the technology of cable voltage drops compensation for high current output system against the GPU power supply structure was researched.the compensation scheme based on cable parameter was discussed in detail. Software and hardware architectures of the digital control system were introduced, including algorithm control system based on FPGA and DSP chips and remote monitoring system based on ARM chip. The software design of FPGA based on Quartus II and the task design of DSP based on DSP/BIOS and the thread design of ARM based on Prototheads were analyzed in detail. The Finite State Machine module of FPGA and the serial communication task of DSP and the ethernet communication thread of ARM were discussed specially.Finally, a 90kW GPU experimental system is designed. The experiment results are carried and analyzed, including open-loop experiment and close-loop experiment based on separation control method and compensation experiment based on cable parameter. It shows that the analyses and design in this paper are reasonable.