Research On15kW Converter For Ultra-high-speed Turbine Generator

Recently, with the development of the distributed power system and multi-electric technology, power systems have been slowly replacing the hydraulic,pneumatic and other mechanical systems in traditional aircraft, in order to make thesecondary side of the power system are allocated in form of electricity, the multi-electric aircraft has become a new development direction. The power system whichbased on Ultra-high-speed turbine generators will become an important researchdirection of aircraft power supply system, the principle is that the turbine is drivenby the gas exhaust plume and high speed air while the aircraft flight to generate thepower. However, its output external features is extremely soft, for it can`t adjust theair pressure and excitation. Because of the generated power`s uncertainly and theload`s randomness cause the energy mismatch between the generator and the load.Therefore, this paper studies on a converter for Ultra-high-speed turbine generatorsand the matching problem in this system, which aimed at the safe operation of thegenerator and continuous supply for the load.This paper analyzes the characteristics of the Ultra-high-speed turbinegenerator power system, analyzed its output characteristics of open-loop system,and studied on the energy match situation between the generator and the load.According to the results, we get the functional requirements of the designedconverter in this paper, that is the converter can achieve constant voltage output andprotect the security of the power system by using the energy matching port tolimiting the speed of the generator when the load is light. Then discussed theapplicability of its topology, and presented a three-port converter which derivedfrom Buck converter, and designed the control strategies of the converter system.Designed the converter parameters and control system, according to theproposed technical specifications. Calculate the Buck inductance, capacitance, andthe energy matching port resistance. Designed the voltage control loop of theconverter to ensure the converter have a good dynamic response and stabilityperformance. In order to achieve high specific power of the converter, the paperuses the thermal simulation method to optimize the geometry of the converter, useProE to design the preliminary geometry, then use Flotherm make the thermalsimulation, optimized the structure based on the simulation results.Built a15kW prototype based on the proposed design, while the paper alsopresents a ultra-high-speed turbine external characteristics simulation equipment,which use a constant power source. The experimental results verify the control method and the design of the prototype reach the design requirements.