Investigation of Energy Savings on Industrial Motor Drives Using Bidirectional Converters

Motor drives is a widely used technology, offering many advantages, such as exceptional speed control and flexibility. Improvement of reliability and efficiency has become a great research interest. Toward this direction and considering the major recent developments in supercapacitor technology, the use of bidirectional energy recovery converters has been introduced in various industrial applications. In this paper, the regenerative braking of a three-phase induction motor controlled by a variable frequency drive will be analyzed and the portion of kinetic energy that can be recovered will be calculated. The main contribution of this paper is a methodology for the estimation of the energy savings that can be achieved from the use of such an energy recovery feature. In addition, the optimum braking duration that maximizes the recovered energy will be investigated. The analysis presented in this paper has been validated experimentally and the results are discussed.