Abstract
Typically, a surface-mounted permanent magnet synchronous machine (SPMSM) has a poor flux-weakening performance due to its low synchronous inductance; hence, its speed is proportional to the supply voltage. A relatively high DC-link voltage is required to operate an SPMSM at higher speeds. This paper proposes a multi-mode multi-speed operation method to overcome this issue. With this method, the total line-to-line back electromotive force (EMF) is modified using the winding switching. Each phase of the stator winding is divided into two equal coils. There are four modes of operation of the machine. In mode I, the three-phase stator winding is connected in a wye configuration. In modes II, III, and IV, the winding is reconfigured such that the sum of the individual back EMFs of the coils exhibits a difference in voltages between the line terminals. The back EMF in these modes decreased by 1.74, 3.67, and 6.49 times, respectively, compared with that in mode I. This resulted in a four-speed operation, with base speeds of 1, 1.97, 3.68, and 7.47 pu in modes I-IV, respectively. Herein, the analytical model of the machine and drive topology are explained and demonstrated. Simulation results obtained using the 2-D finite element method are presented along with the experimental measurements to verify the feasibility of the proposed method.
Highlights
During the early stages of the development of electrical machines, AC machines were regarded as constant-speed machines, which restricted their implementation
This paper proposes a modified winding switching scheme based on reference [20] to achieve a multi-mode multispeed operation of an surface-mounted permanent magnet synchronous machine (SPMSM)
This paper proposed a multi-mode operation method using winding switching, which realized the multi-speed operation of SPMSMs
Summary
During the early stages of the development of electrical machines, AC machines were regarded as constant-speed machines, which restricted their implementation. Various methods have been proposed to improve the fluxweakening performance of SPMSMs. Fractional-slot concentrated windings have a high leakage inductance, which in combination with magnetizing inductance results in a higher overall Ld inductance, improving their constant-power operation [2], [3]. In reference [20], a cumulative/differential machine operation that implemented winding switching for a single inverter was reported This method achieved two-speed operation, and the back EMF in the differential mode was reduced 3.52 times compared with that in the cumulative mode. PROPOSED MULTI-MODE MULTI-SPEED OPERATION METHOD The proposed operating method requires a special winding arrangement, which is described as follows: the machine is a 4-pole 24-slot SPMSM, with a three-phase winding having a coil pitch of five. EMF and torque will be the highest In this mode, the machine comprises a three-phase wye-connected winding with the following phases: phase U—coils A and X, phase. Where Rll and Ld ll are the line resistance and line synchronous inductance, respectively, in mode I
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.
