Abstract
The industrial application of electric machines has grown in the last decades, thanks to the development of microprocessors and power converters, which have permitted their use as variable-speed drives. Although three-phase machines are the common trend, the interest of the research community has recently focused on machines with more than three phases, known as multiphase machines. The principal reason lies in the exploitation of their advantages in terms of reliability, i.e., post-fault operating capability. Additionally, multiphase machines provide a better current distribution among phases, and lower current harmonic production in the power converter, than conventional three-phase machines. However, multiphase drive applications require the development of complex controllers to regulate the torque (or speed) and flux of the machine. In this regard, direct torque controllers have appeared as a viable alternative due to their easy formulation and high flexibility to incorporate control objectives. However, these controllers face some peculiarities and limitations in their use that require attention. This work aims to tackle direct torque control as a viable alternative for the regulation of multiphase drives. Special attention will be paid to the development of the control technique and the expected benefits and limitations in the obtained results. Case examples based on symmetrical five-phase induction machines with distributed windings in the motoring mode of operation will be used to this end.
Highlights
It is expected that about 80% of all the produced energy will be used by electric drives by 2030, playing a major role in the automotive field, where they will dominate almost50% of the market by that year
Direct torque control emerged in the late 20th century to become an alternative to vector controllers in conventional three-phase drives, where robustness, simplicity, and computational cost were desirable regulation characteristics
We note that interest in direct torque controllers (DTC) has been barely explored or experimentally analyzed in multiphase drives, this paper tries to reduce this gap, proposing DTC
Summary
It is expected that about 80% of all the produced energy will be used by electric drives by 2030, playing a major role in the automotive field, where they will dominate almost50% of the market by that year. The main interest in the proposal was that the higher number of phases yields a torque ripple three times lower with respect to the equivalent three-phase case due to a better power distribution per phase, this being one of the most reported problems in conventional drives at that time. It was not until the end of the 20th and the beginning of the 21st centuries that the interest of researchers in multiphase machines was renewed due to two main reasons. There is the development of microelectronic technology and the appearance of powerful electronic devices with the ability to implement control algorithms in real time, such as digital signal processors (DSPs) and field-programmable gate arrays (FPGAs)
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call