Analysis of the electromechanical behaviour of the subsynchronous cascade drive

In the present paper an investigation of the electromagnetic torque pulsation of the subsynchronous cascade drive (SCD) is carried out. The influence of the asynchronous machine's speed, of the load torque-speed characteristics and of the asynchronous machine's parameters on the torque pulsation is investigated and analyzed. The conclusions drawn by the simulation results of a large drive (4 MW), installed in a cement industry, are verified by experimental investigation using a small drive in the laboratory. The knowledge of the pulsation amplitude for different speeds and parameters is essential in order to examine the torsional behaviour of the mechanical subsystem, something which is necessary in this kind of drives.