Torque capability and control of a saturated induction motor over a wide range of flux weakening

The first part of this paper covers an investigation of the maximum torque which an induction motor with saturated air gap inductance can generate over its permitted speed range, when voltage as well as current are limited. From the investigation, three regions of operating speed are identified, based on limiting quantities which determine the maximum obtainable torque. In each of these regions a different control strategy must be applied. When maximum torque is not required, efficiency can be optimized but this strategy should not be applied at low torque levels when good dynamic performance is required. The second part illustrates how a modified rotor flux oriented control strategy is applied to achieve full utilization of the torque capability over the whole speed range. Several measures for improving dynamic and transient behavior of the drive in the flux weakening region are suggested. Performance of the new control strategy is verified by experiments. >

[1]  O. Ojo,et al.  Steady state performance evaluation of saturated field oriented induction motors , 1990, Conference Record of the 1990 IEEE Industry Applications Society Annual Meeting.

[2]  Werner Leonhard,et al.  Control of Electrical Drives , 1990 .

[3]  Yau-Tze Kao,et al.  Analysis and design of microprocessor-based vector-controlled induction motor drives , 1992, IEEE Trans. Ind. Electron..

[4]  R. D. Lorenz,et al.  Saturation effects in field-oriented induction machines , 1990 .

[5]  J. Fetz,et al.  High efficiency induction motor drive with good dynamic performance for electric vehicles , 1993, Proceedings of IEEE Power Electronics Specialist Conference - PESC '93.

[6]  Seung-Ki Sul,et al.  Maximum torque control of an induction machine in the field weakening region , 1993, Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting.

[7]  O. Ojo,et al.  Steady-state optimization of induction motor drives operating in the field weakening region , 1993, Proceedings of IEEE Power Electronics Specialist Conference - PESC '93.

[8]  R. GABRIEL,et al.  Regelung der stromrichtergespeisten Drehstrom- Asynchronmaschine mit einem Mikrorechner/ Control of the converter-fed three-phase induction motor by a microprocessor , 1979 .

[9]  R. D. Lorenz,et al.  Selection of Flux Level in Field-Oriented Induction Machine Controllers with Consideration of Magnetic Saturation Effects , 1987, IEEE Transactions on Industry Applications.

[10]  H. Grotstollen,et al.  Field oriented control of an asynchronous motor with a very wide region of flux weakening , 1992, [1992] Proceedings of the IEEE International Symposium on Industrial Electronics.

[11]  Mats Alaküla,et al.  Field-oriented control of saturated induction machines , 1990 .