Effect of Winding Configuration on Six-Phase Induction Machine Parameters and Performance

Abstract

Six-phase induction machines have mostly shown promise in high-power electric drive applications as well as wind energy conversion systems. Different winding configurations for six-phase stators have been published, namely, dual three-phase (D3P), symmetrical six-phase (S6P), and asymmetrical six-phase (A6P) winding layouts. Although a body of research investigating six-phase machines and their control for different six-phase winding arrangements exists, a thorough comparative study between these different arrangements in terms of machine parameters and performance, has not been done so far. This paper employs a 12-phase stator with a configurable terminal box to compare different six-phase configurations by simply reconnecting the stator terminals of the twelve phases in different manners to obtain an equivalent six-terminal stator. This way, the same stator machine dimensions and copper volume will be assumed for all connections. The comparative study focuses on the effect of winding connection on machine parameters of the different subspaces, phase current quality and machine characteristic curves. Experimental validation has been carried out using a 1kW prototype system.

Assessment of Predictive Current Control of Six-Phase Induction Motor With Different Winding Configurations

“…Although it has been shown in [13] that the winding layout will affect the equivalent parameters of the sequence circuits, the sequence circuits shown in Fig. 2 will be the same for all winding configurations.…”

“…This recommended chorded winding design is commonly employed in practical six-phase stators. The terminals of the 12 phases are externally reconfigured to form any of the three six-phase winding configurations, as detailed in [13]. The study showed the following interesting conclusions:…”

“…In order to achieve a fair comparison, same stator with the same copper volume and dimensions has been used for all winding configurations. The theoretical findings have experimentally been validated using a 1 kW twelve-phase machine that can externally be reconnected to form any of the three different windings of SPIM [13]. The current study is limited to healthy case with isolated neutrals arrangement, which is the preferably employed neutral arrangement under healthy conditions.…”

“…As a result, various configurations of six-phase induction machine (SPIM) has been proposed in literature consisting of two three-phase winding sets with an arbitrary spatial phase shift angle between the two sets [13], [14]. Based on the winding arrangement, six-phase machine could be classified into dual three-phase (D3P), asymmetrical six-phase (A6P), and symmetrical six-phase (S6P) machines with a spatial phase angle between the two-winding sets of 0 0 , 30 0 , and 60 0 , respectively, as shown in Fig.…”

“…However, it has been proven that with an appropriate choice of the switching frequency, the harmonic contents and, thus, the developed torque for the three configurations may fairly be comparable [17], [18]. The recent study introduced in [13] has compared the parameters and performance of three equivalent six-phase machines having same dimensions and copper volumes with the three possible winding configurations (D3P, A6P, and S6P). This has been carried out using a 12-phase machine with a double layer winding and a 5/6 coil span.…”