Design optimization of integrated rotor-less inductors for high-speed AC drive applications

Abstract

--Discrete sub-system due to passive elements in motor drive require functional and structural integration to make efficient and power dense overall system. Such power dense system is the prerequisite in aerospace and marine applications. This paper presents the design optimization of integrated rotor-less inductors for high speed AC drive applications. Different slot-pole combinations are considered in this process. The single layer (SL) and double layer (DL) windings are chosen with concentrated winding (CW) and distributed winding (DW) configurations. The rotor-less inductors are optimized and compared in this paper with EE core inductor in terms of total losses, weight and AC copper resistance at both fundamental frequency and switching frequencies (10, 15 and 20 kHz). The comparative analysis between EE core and rotor-less inductors has shown a significant reduction in total losses and AC copper resistance at both fundamental frequency and all switching frequencies.

Design of an Integrated Inductor for 45kW Aerospace Starter-Generator

“…The author of [3][4][5] introduced the novel options to integrate the passive filter inductors within the housing of the electrical machine as shown in Fig. 2.…”

“…6 indicates the physical core dimensions. The iron core area relates the flux permeance capabilities whereas the window defines the current conduction capabilities of an inductor which is limited by the conductor's thermal characteristics [4][5][6]21].…”

“…The back iron width is adjusted to keep the identical flux density in the core and the slot opening height is increased to keep the uniform flux density throughout the stator slots. Since it is a rotor-less inductor, phase inductance is only controlled by the slot opening unlike integrated rotational inductor in [3,4]. Fig.…”

“…This leads to discrete sub-systems which require a functional and structural integration of each sub-system in order to make an efficient and power dense overall system. Such power dense system is vital in aerospace and marine applications [1][2][3][4][5]. In order to overcome these drawbacks, the integration of passive components need to be introduced both from functional and physical point of view [1][2][3][4][5].…”

“…Thus, applications where high power density is needed, integrative approach seems to be the best solution. This paper will look into a design of an integrated rotor-less inductor which was proposed in [2][3][4][5] for a 45kW aerospace starter-generator. This paper investigates the impact of high current density on the inductor design, effectiveness of integration and compares its design with traditional core aircooled inductor in terms of its weight and volume.…”