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In hybrid and electric vehicles, the control of the electric motor is a critical component of vehicle functions such as motoring, generating, engine-starting and braking. The efficient and accurate control of motor torque is performed by the motor controller. It is a complex system incorporating sensor sampling, data processing, controls, diagnostics, and 3-phase Pulse Width Modulation (PWM) generation which are executed in sub-100 uSec periods. Due to the fast execution rates, care must be taken in the software coding phase to ensure the algorithms will not exceed the target processor's throughput capability. Production motor control development often still follows the path of customer requirements, component requirements, simulation, hand-code, and verification test due to the concern for processor throughput. In the case of vehicle system controls, typically executed no faster than 5-10 mSec periods, auto-coding tools are used for algorithm development as well as testing.

Due to the need for improving fuel economy, reducing tailpipe emissions and the trend towards increasing electrical content in automobiles, hybrid drivetrains are being considered by the automotive industry. In the foreseeable future, in order to address the drive towards hybridization, vehicle manufacturers will begin to use a 42 volt-based architecture in conjunction with an integrated starter and generator system. Depending on the desired power level and allowable changes to the vehicle drivetrain, either an Integrated Starter Generator which mounts between the engine and the transmission or a Belt Alternator Starter (BAS) system which mounts on the accessory belt can be used. This paper will examine the impact of choosing either a Permanent Magnet (PM) machine or an Induction machine for a BAS application. The impact of the technology on the electric machine design process, power stage implementation, control strategy and overall system design philosophy will be discussed.

Over the next several years, vehicle manufacturers will begin to use a 42 volt based system to integrate the starter and generator into one unit known as an integrated starter-generator (ISG). The ISG and its associated electronics and battery pack form a system that has the ability to perform torque smoothing of the driveline, electrical launch assist, regenerative braking, high power generation, engine stop/start, and other features. One of the important tasks to be performed by the ISG is starting the internal combustion engine under extremely low temperature conditions. Traditionally, the 12-volt cranking motor has performed this solitary task over the last sixty years. The ISG system is capable of incorporating the cranking motor task and must be designed to perform this function over the full automotive temperature range. The cold starting requirements have a great influence on the design of any ISG system.

Hybrid electric vehicles have the potential to reduce air pollution and improve fuel economy without sacrificing the present conveniences of long range and available infrastructure that conventional vehicles offer. Hybrid vehicles are generally classified as series or parallel hybrids. A series hybrid vehicle is essentially an electric vehicle with an on-board source of power for charging the batteries. In a parallel hybrid vehicle, the engine and the electric motor can be used to drive the vehicle simultaneously. There are various possible configurations of parallel hybrid vehicles depending on the role of the electric motor/generator and the engine. In this paper, a comparative study of the drivetrains of five different hybrid vehicles is presented. The underlying design architectures are examined, with analysis as to the tradeoffs and advantages represented in these architectures.

This paper analyzes hysteresis (HCR), delta modulation (DCR), and pulse width modulation (PWMCR) current regulators for switched reluctance machines. The current regulators are implemented in real-time for a 6/4 3-phase 15 kW switched reluctance machine (SRM). The comparative study of the performance of the current regulator is focused on the current transient response, deviation from the current reference, acoustic noise, and vibration for soft chopping and hard chopping mode of operation.