Research on direct torque control based asynchronous dynamometer for dynamic emulation of mechanical loads

摘要

Purpose - The purpose of this paper is to present a novel dynamometer employing direct torque control (DTC) method, which has wide application prospects in the industry field. Design/methodology/approach - Conventional dynamometers such as eddy dynamometers waste energy, waste water, and operate inconveniently. In this paper, a novel digital electric power dynamometer is proposed which uses a three-phase squirrel-cage induction machine as the loading machine. The system uses a digital signal processor named TMS320LF2407A as the controller to control the three-phase induction machine employing an improved DTC for precise torque tracking. The power dynamometer is in generating mode, using the common-DC-bus to implement energy circulating or through the energy regenerating unit feeding back the networks energy. A direct-torque-controller dynamometer allows very fast torque responses and flexible control. The load torque is regulated conveniently and swiftly. Findings - Simulations and experiment results show that the design of the electronic power dynamometer based on improved DTC is proper, the control is simple, and digitized and is simple to use. Research limitations/implications - The precise torque controls are the main limitations for the high-performance power dynamometer applied. Torque ripples should be small. Practical implications - Power dynamometer based on DTC is one of the novel ones worth being generalized in place of conventional dynamometers. Originality/value - The new approach of a novel digital power dynamometer based on an improved DTC is introduced.