Concerns over the air quality in many urban areas has generated an interest in electrically driven commuting vehicles. Multi-motor drive train arrangements, and in particular, dual motor arrangements are attractive for such vehicles because of their mechanically simple design (no differential required) and traction and regenerative braking control capability on low friction surfaces. However, such configurations normally require two power inverters. The high cost and volumetric packaging needs of the inverter make such dual motor/dual inverter configurations economically less competitive than a single motor, single inverter, mechanical differential arrangement.;An economically attractive alternative could be a single inverter, dual induction motor configuration. Because the induction motor is able to produce torque over a range of rotor speeds while operating at a fixed frequency, equal torque can be maintained on both rotors even when rotor speed are different, as in a turn. However, in transitions between steady-state operating modes, it is well know that transient torque oscillations can occur if proper control techniques are not employed. Therefore, this work presents a methodology for controlling the transient as well as steady state torque production from each rotor of a dual induction motor drive powered by a single power inverter. This work includes the theoretical formulation of a suitable "dual motor" machine model from which the required control relations are derived. The resulting control relations are similar in form to single motor field-oriented control laws, but allow mean and differential torque to be controlled. Experimental test results demonstrate the transient torque control capabilities of the method.
展开▼
