Power factor correction of an electrical drive system based on multiphase machines

Abstract

This paper deals with the energy efficiency improvement of an electrical drive which can be used both in wind energy conversion or motor drive applications. A power factor (PF) control scheme is presented allowing energy efficiency enhancement and optimization in high power variable-speed drives based on multiphase machines. Thus, the double-star induction machine is taken, as an example of multiphase machines, to introduce the principle of the study presented in this paper. In fact, the purpose of this paper is to maintain the PF of the power-winding, of the double star induction machine, in vicinity of unity whatever the drive operating point. Also, this control scheme can be generalized for several kinds of multiphase machines. Keywords-Double fed induction machine; energy efficiency; multiphase machine; power factor control (PFC).I.

Electric Power Flow Control in Double Three-Phase Machines without Shift between Magnetic Axes

“…The mathematical model of the machine examined in this paper is derived using the multi-stator approach [16,17]. This approach ensures independent control of each threephase winding, allowing for precise control of the contribution that each winding makes to the electromagnetic torque production and power transfer between windings.…”

“…Using a vector notation of Kirchhoff's voltage low, the machine model can be described in the phase domain with two equations for the stator windings and one equation for the rotor winding, as shown in Equation (1), where [R s ] and [R r ] are the unit matrices of the stator and the rotor winding resistance. The mathematical model of the machine examined in this paper is derived using the multi-stator approach [16,17]. This approach ensures independent control of each threephase winding, allowing for precise control of the contribution that each winding makes to the electromagnetic torque production and power transfer between windings.…”

“…The distinct features of multi-phase machines offer significant benefits in specific applications related to renewable energy sources (RES) [10] and electrification in transportation, predominantly in the context of electric vehicles (EVs) [11,12], but also in electric aircraft [13,14] and ship propulsion systems [15]. In industrial applications conventionally linked to three-phase machines, multi-phase machines emerge as a compelling alternative that can simultaneously handle additional challenges [16][17][18].…”

Performance Improvement of Grid-Connected Induction Motors through an Auxiliary Winding Set

“…It is assumed that the two polyphase stator windings [19][20][21][22][23] are distributed in order to produce sinusoidal magneto-motive forces; moreover, the effects of the saturation of the Energies 2021, 14, 2178 3 of 16 magnetic core are neglected, while iron losses are considered according to [24]. The voltage and flux equations of the DOL-DWIM, written in complex form f qd = f q − j f d , according to an orthogonal qd reference frame rotating at the angular frequency ω e of the input stator voltage vector, are given by [23]:…”