Starter-Generator System for Gas Turbine Engine Based on AC-AC Converter

In recent years, there has been a rapid growth of research and development on cross-platform integration of various aircraft systems such as hydraulic, fuel, air conditioning system, power supply system, auxiliary power unit (APU), mid-flight engine, etc. Likewise, there is an increasing trend towards avoiding hydraulic, pneumatic and mechanical components in favour of electrical systems that have lower losses in energy conversion and higher level of work progress regulation. Systems for generating electrical energy of variable frequency and a constant value of the generated voltage are already available on board the medium-haul aircraft. In this case, devices, which ensure frequency stabilization, are excluded from the system. Aircrafts such as the Boeing-787, A-380 and the new Russian aircraft MC-21 may be cited as examples. The article presents a starter-generator system for the mid-flight engine of the aircraft based on the synchronous motor with permanent magnets (PMSM) and semiconductor converter. The system is built using the algorithm of the adaptive estimator based on the flux linkage, by which it is possible to refuse from the speed sensor and position sensor rotor, which reduces mass and dimensions and reduces the number of information lines of the system. The results of mathematical modelling of the system in the starter mode are also given in the article.