Sensorless Control of Brushless Doubly-Fed Reluctance Machines using an Angular Velocity Observer
ABSTRACT The brushless doubly-fed reluctance machine (BDFRM) has been considered by academic and industrial communities as a potential alternative to conventional doubly-excited wound rotor induction machines (DEWRIM) in variable speed applications with limited speed ranges such as large pumps and wind turbines. While offering similar cost benefits, afforded by the use of partially-rated power electronics, the BDFRM has the following important advantages over DEWRIM-brushless design and consequent maintenance-free operation. The main purpose of this paper is to further improve the reliability and cost- effectiveness of the BDFRM drive by proposing a new observer based algorithm for speed and direct torque (and flux) control (DTC) of this machine without a shaft position sensor using a maximum power factor control strategy as a case study. The developed sensorless control scheme has been experimentally verified on a small BDFRM prototype, and obtained test results have shown that it can perform very well down to zero applied frequency to the inverter-fed winding this being difficult or impossible to achieve with traditional DTC concepts.
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ABSTRACT: A methodology for the steady-state performance analysis and design of the doubly fed reluctance motor (DFRM) is presented in this paper. Emphasis is placed on the linear model of the DFRM, but magnetic nonlinearities are also characterized. A prototype 2 hp DFRM is designed and built in comparison with an induction motor. Performance of the prototype 2 hp DFRM motor is analyzed thoroughly and is supported by actual measurements, wherever availableIEEE Transactions on Industry Applications 10/1996; · 1.67 Impact Factor
Conference Proceeding: Optimal torque per amp for brushless doubly fed reluctance machines[show abstract] [hide abstract]
ABSTRACT: This paper documents the finite element (FE) analysis of a range of rotors for a brushless doubly fed reluctance machine (BDFRM). The aim to this work is to increase the understanding of the BDFRM and determine an optimal rotor design for torque generation and machine power factor. The results of the analysis show a significant contrast between the rotors for a synchronous reluctance machine and BDFRM. The optimal stacking factor for the BDFRM is 0.86, whereas the synchronous reluctance optimum is 0.5. Even though the two rotors can be physically identical, the resemblance is superficial.Industry Applications Conference, 2005. Fourtieth IAS Annual Meeting. Conference Record of the 2005; 11/2005
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ABSTRACT: In this paper, the concept and implementation of field-orientation control (FOC) of a doubly excited brushless reluctance machine (DEBRM) for variable-speed drives and generating systems are presented. A stator-flux-orientation scheme is employed to achieve decoupled control of torque and reactive power. A 2 HP DEBRM prototype system with a digital signal processor (DSP)-based controller and a bidirectional power converter is built to verify the theoretical analysis. Computer simulation and laboratory experimental results are shown in excellent agreementIEEE Transactions on Industry Applications 02/1998; · 1.67 Impact Factor