Development of Technology for Electrically Driven Powertrains in Hybrid Electric Vehicles

INTRODUCTION RECENT years have seen many different initiatives aimed at bringing about a low-carbon society and it is anticipated that, in the automotive field, HEVs (hybrid electric vehicles) that offer significant improvements in fuel consumption will precede EV (electric vehicles) in becoming the mainstream of future vehicle markets. HEVs achieve low fuel consumption and powerful performance by combining an engine and electric motor with control that operates each in its optimum range. Hitachi has traditionally been strong in the field of technology for electric motor development and in addition to three-phase AC (alternating current) motor control systems that are typically supplied in the form of power modules, Hitachi also supplies vehicle system solutions and has developed small, lightweight, highly efficient, and low-cost HEV systems. This ar t ic le descr ibes system simulat ion technologies and the trend toward smaller size and higher output in the electric motors and power inverters used in electric drive systems for HEVs.