Control of a High Impedance Generator

  • Ana Michelle Dominguez Rodriguez

Student thesis: Phd


This thesis presents the design and analysis of a control technique for a 70 kW five-phase high-impedance permanent-magnet generator (PMG) system conceived as a more-electric aircraft aero-engine embedded generator technology. The control design must preserve the fault-tolerance properties of the high-impedance machine whilst providing high power quality and DC voltage regulation over the full speed and load operating range. The generator’s fault tolerance is given by its magnetically, thermally and electrically isolated high-impedance phases. Thus, to sustain the fault tolerance characteristics, the generator system is treated as five separate subsystems, i.e., per-phase AC to DC voltage converters, current sensors and actuating controlling algorithms. The derived controllers are designed for unity power factor operation, DC bus voltage regulation, power load sharing, and high-speed field weakening operation. Mathematical modelling of the loops and detailed frequency domain controller design is presented. Two time-domain simulation models and a hardware-in-the-loop emulator system are used to validate the controller’s effectiveness throughout the entire load and speed range of the high-impedance PMG system.
Date of Award1 Aug 2019
Original languageEnglish
Awarding Institution
  • The University of Manchester
SupervisorRebecca Todd (Supervisor) & Andrew Forsyth (Supervisor)


  • Aero-engine embedded generator
  • Unity power factor operation
  • Field weakening control
  • Power factor correction
  • Power conversion
  • Permanent-magnet generator
  • Voltage source converter control
  • Active rectifier
  • Control design
  • Fault-tolerant
  • High-impedance generator

Cite this