As a result of the uneven voltage vector contribution to the control of stator flux and torque in a direct torque controlled (DTC) induction machine, stator flux magnitude droops at every switching sector transition, particularly when the machine is running at low speed with a heavy load. A simple strategy rotates the conventional DTC switching sectors according to the states of the flux and torque hysteresis comparators and a gating signal. The applied voltage vector thereby maintains stator flux magnitude at the transition between switching sectors and hence improves the phase current without deteriorating the torque response. A thorough simulation analysis of stator flux droop is presented, and both simulation and experimental results confirm the effectiveness of the proposed strategy. © IEE, 2004.
|Translated title of the contribution||Minimisation of flux droop in direct torque controlled induction motor drives|
|Article number||Issue 6|
|Pages (from-to)||694 - 703|
|Number of pages||10|
|Journal||IEE Proceedings: Electric Power Applications|
|Publication status||Published - 7 Nov 2004|