Five-phase Synchronous Machine Research Articles

Predictive control of a series-connected two five-phase synchronous magnet permanent machines

The work presented in this paper focuses on studying the concept of two five-phase permanent magnet synchronous machines connected in series, powered by a single five-arm converter, in order to considerably minimize circulating currents. Firstly, we modeled a system composed of two identical five-phase synchronous machines, whose stator windings are connected in series. This modeling aims to demonstrate that the control of each machine in the group can be independent of the other, even though both machines are powered by a single five-phase converter. Then, we carried out the predictive control of the two five-phase machines connected in series. This control is based on the prediction of future switching states, which are managed via the discrete model of the system. The optimal switching state is obtained according to a predetermined cost function. To demonstrate the features of the presented control algorithm, the results of the simulation conducted using MATLAB/Simulink are presented and discussed to evaluate the performance and efficiency of the independent control of the two five-phase synchronous machines connected in series.

Magnetic skew interface in five-phase ferrite assisted synchronous reluctance motor model

Permanent Magnet Assisted Five-Phase Synchronous Machine is analytically modeled in the rotating (dq1dq3) reference frames. The cross saturation and space harmonics are captured in the magnetic flux maps obtained from static 2D finite element (FE) analysis. In this paper, a method to incorporate the skewing effect in the flux map distribution for the first and third harmonic is presented. The original flux for one motor segment is used to calculate fluxes of the first and third planes in the consecutive skewing segments. Respective rotator operators allow to sum the contribution from axial slice and shift the resulting map to the desired zero reference position. Eventually, a dynamic model is established on the new corrected flux maps. FE and experimental validations have been performed to confirm the authenticity of the proposed technique.

Constant-Parameter Voltage-Behind-Reactance Modeling of Five-Phase Synchronous Machines With Air-Gap Flux Harmonics

Five-phase electric machines possess several distinct features and are sometimes considered in vehicular power systems and various special-purpose energy sources. Design and analysis of such machine-converter systems are highly dependent on simulation software programs, where accurate and numerically efficient dynamic models of five-phase synchronous machines are essential. Depending on levels of fidelity and interfacing compatibility, the traditional models for five-phase machines include the coupled-circuit-phase-domain (CCPD) and qd 0 models. To achieve a computationally-efficient model suitable for many simulation programs, in this paper, a new constant-parameter voltage-behind-reactance (CPVBR) model is proposed for five-phase synchronous machines where a simple interfacing circuit is achieved with constant RL branches. The proposed model is validated by experimental measurements and simulation studies. The proposed CPVBR model is demonstrated to have superior numerical efficiency and simulation speed compared to the existing conventional models.

A Vectorial Approach for Generation of Optimal Current References for Multiphase Permanent-Magnet Synchronous Machines in Real Time

This paper deals with the generation of optimal current references for multiphase permanent-magnet (PM) synchronous machines in normal or fault mode (open-circuited phases). Current references are computed in order to keep a constant torque while minimizing instantaneous joule losses. In comparison with commonly used scalar methods, a vectorial approach makes it possible to reduce the number of computations in order to generate optimal current references in real time. In addition to this, since current references are expressed in terms of physical parameters of the machine, this approach can be used to evaluate the influence of machine parameters over the control performances. Finally, experimental results of a surface-mounted PM five-phase synchronous machine are provided in order to demonstrate the proposed strategy.