Abstract
This paper presents a novel dual-mode wound rotor synchronous machine (DWRSM) for variable speed applications. The proposed machine combines the advantages of both the conventional wound rotor synchronous machine (CWRSM) and the brushless wound rotor synchronous machine (BWRSM). Unlike the existing BWRSM, through the dual-mode operation of the proposed machine, constant torque is achieved in the constant torque region by operating the machine in mode-I, i.e., as a CWRSM, and constant power is achieved in the field weakening region by operating the machine in mode-II, i.e., as a BWRSM. The mode change is performed through an additional thyristor drive circuit. The airgap magnetomotive force (MMF) in both modes is derived analytically. To verify this principle, finite element analysis (FEA) and an experiment on a 1- horsepower prototype machine was performed, and key influential factors were verified. The transients in the stator currents and torque during the mode change was analyzed. The test results validated the correctness of the theory and the FEA results.
Highlights
Variable speed applications such as electric vehicles (EVs), compressors, pumps, blower fans, rolling mills, generators, washing machines, etc., are being developed as a means to address environmental concerns and to solve the problems associated with internal combustion engine vehicles [1]–[3]
In [18], different machine topologies including those of Permanent magnet synchronous machines (PMSMs), induction machines (IMs), and wound rotor synchronous machines (WRSMs) have been studied for EV application
DUAL-MODE TOPOLOGY Based on the existing brushless topology shown in Fig. 1(a) which has a low starting torque due to the lack of any external rotor excitation [25], the proposed dual-mode wound rotor synchronous machine (DWRSM) is designed to introduce a topology that can produce constant torque below the base speed when working as a conventional WRSM (CWRSM), whereas it exhibits constant power above the base speed when working as a brushless wound rotor synchronous machine (BWRSM)
Summary
DUAL-MODE TOPOLOGY Based on the existing brushless topology shown in Fig. 1(a) which has a low starting torque due to the lack of any external rotor excitation [25], the proposed DWRSM is designed to introduce a topology that can produce constant torque below the base speed when working as a CWRSM, whereas it exhibits constant power above the base speed when working as a BWRSM. For mode-I operation of the DWRSM, the three phase alternating currents (ACs) excite the stator windings and generate the rotating MMF. The second term in equation (14) is the sub-harmonic MMF term in the airgap MMF, which is responsible for the brushless excitation of the rotor in mode-II This sub-harmonic MMF induces the voltages in the same pole-pair rotor harmonic winding, which is rectified by the rotating rectifier mounted on the rotor periphery, and a DC current to the field winding of the machine is supplied. The proposed DWRSM is operated in the constant power region by a field weakening control using negative d-axis stator currents
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
