Powering the Future of Industry: High-Power Adjustable Speed Drive Topologies

The development of advanced and more cost-effective industrial processes, driven mainly by the economy of scale and higher production rates, has boosted the presence of high-power (HP) drives in several industrial sectors. In addition, efficiency has become a major figure of merit in today's industry because of the economical benefits along with the importance of sustainability. This has led to a higher demand for adjustable speed drives (ASDs), increasing their percentage of share in a market greatly dominated by standard direct grid-connected motor drives (still more than 80% in several industrial sectors). Other factors that have contributed to this recent shift in trend are the developments in power electronics, the increase in reliability of power converters, and the fact that life-cycle costs (initial cost plus cost of operation during the projected life of the drive) have become more important than initial investment in the drive-selection process, especially in HP applications. This article gives an overview of the present state of technology of HP-ASD topologies.