Comparison of three-phase current controllers for permanent magnet synchronous machine drives

Open Access
Author:
Chen, Shuo
Graduate Program:
Electrical Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
June 09, 2014
Committee Members:
  • Jeffrey Scott Mayer, Thesis Advisor
  • Jeffrey Louis Schiano, Thesis Advisor
  • Kultegin Aydin, Thesis Advisor
Keywords:
  • Field-oriented control
  • bandwidth limitation
  • Simulink
Abstract:
Field-oriented control (FOC) is a defacto standard for the high-performance control of inverter-driven ac electric machines. FOC requires regulation of the three-phase ac stator winding currents within a velocity/position control loop. It is usually accomplished using PI control in the synchronous reference frame in conjunction with appropriate reference frame transformations for the current feedback signals and voltage actuation signals. In this thesis, transfer function models have been derived for a complete drive system with FOC, and are used to compare the characteristic response of the various approaches. Among these transfer functions, the use of the synchronous reference frame starts from practical considerations. In particular, all the electrical variables in this frame are dc quantities in the steady state; thus, compensator bandwidth is ostensibly a minor concern. Analysis of the closed-loop system, however, reveals a potential hidden cost in this approach: it imposes a bandwidth limitation on the velocity/position control loop. A set of Simulink models for drive system components has also been developed to investigate the large signed, non-linear response of these systems with different controllers. The Simulink models also permit selective modeling of non-idealities such as blanking time.