Strategies and a Computer Aided Package for Design and Analysis of Induction Machines for Inverter-D - Industry Applications Conference, 1995. Thirtieth IAS Annual Meeting, IAS '95., Conference Record

Induction machines designed for inverterdriven variable speed systems is different from those powered directly from utility power lines. In this paper, the design strategies of inverter-driven induction machines are discussed. This is followed by a description of a computer aided design and analysis package specifically for this purpose. The program package permits integration design of machines with inverters, comprehensive performance analysis, and system optimization, resulting in 20-30% more power density for the induction machine than that designed for direct utility power supplies by convention method. Design and performance analysis results are presented to substantiate the conclusions. Since the advent of modern AC variable systems, induction machine drives have been investigated extensively, resulting in many successful improvements. In these investigations, the primary concern has been given to the development of solid-state converters and control algorithms [1-4]. However, the electrical machine design has not gone any profound changes compared to the solid-state inverter counterpart within the same system. Nevertheless, recent progress in PM, switched reluctance, and synchronous reluctance machines has indicated a great potential of designing an electric machine as part of the synergistic design of the power invertedmotor package. The importance of designing a so-called inverter-driven electrical machine has been fully verified. At present, while the nontraditional machines, such as the switched reluctance and axially laminated synchronous reluctance machines have attracted considerable amount attention for variable speed systems [5-81, the traditional induction machine can not be neglected for its very low cost, simple and rugged structure, and well developed control algorithms [ 9, IO]. To enhance the performance and reduce the cost of an induction machine drive, this paper presents the design strategies of an inverterdriven induction machine. First, the paper compares the operation conditions of an induction machine operated from an inverter, as opposed to those powered directly from commercial power lines. Design freedom gained by using inverter are highlighted. Then, the basic design strategies for an inverter-driven induction machine are explored. In particular, a set of equations are discussed to characterize the design and performance analysis of an inverterdriven induction machine. Based on these discussions, a computer program package capable of designing and conducting electromagnetic, thermal and mechanical analysis is developed. A family of parametric curves are generated to illustrate the advantages of inverter driven induction machine designs for a wide range of power ratings. A specific example is given to detail the design and performance analysis of an inverter driven induction machine as compared to that of a conventionally designed one. 0-7803-3008-0/95 $4.00