Study of the influence of the leading angle on the operating characteristics of a current source inverter fed synchronous motor drive system

The present study examines limitations of the torque capabilities of a current source inverter (CSI) fed synchronous motor drive system using leading angle-dependent commutation inductance and considering the presence of damper winding in both direct and quadrature axis. A computing program developed in Matlab-Simulink for the complete model of the CSI fed synchronous motor considering the sub-transient quantities allows the evaluation of electromagnetic torque and damper flux linkages. Also, the influence of variable finite value of the d.c. link inductance on the minimum frequency at which the natural commutation is still safe, is studied. The computed and simulated results are validated by comparison with the measurements carried out on an experimental bench (with a 3.2 kW synchronous motor) at load motor operation.