Two-converters based synchronous operation and control of a brushless doubly-fed reluctance machine

摘要

The Brushless Doubly Fed Reluctance Machine (BDFRM) has promising prospect as a commercial machine, since it's a low cost, low maintenance machine. It does not require brushes, slip rings, rotor circuit or magnets. Having a robust winding-free ducted rotor, it can also work with a simpler control technique than a doubly fed induction generator (DFIG). This paper focuses on this side of BDFRM research. An analytical magnetic design process is carried out, and a prototype machine is built based on the proposed optimum design. Subsequently, two -converters based control approach and real-time synchronous operation are investigated. BDFRM analysis for synchronous operation two sets of 3 -phase windings with different numbers of magnetic poles are wound on the stator. The magnetic pole numbers of the windings chosen for this BDFRM. Control of power flow between the windings and the rotor shaft occurs through the salient rotor design, which modulates the magnetic coupling between the windings. Structural FEA has been carried out on several variations to find out the optimized ducted rotor. The current errors are fed as the inputs to the four current PI controllers. The outputs of the current controllers are V_qd8. and V_qd4which are applied to the inverse Park transformation modules. In this test, the BDFRM drive is operated as a synchronous machine at different speed levels with a fixed dc field (4 -pole winding) current to yield optimum torque output. The experimental torque and output power responses. This work discusses the analysis and control approach for a two -converters based synchronous operation of a prototype BDFRM. The motor drive is also tested in real-time.