**ABSTRACT:**

Efficiency improvement of motor drives is important not only from the viewpoints of energy loss and hence cost saving, but also from the perspective of environmental pollution. Several efficiency optimization methods for induction motor (IM) drives have been introduced nowadays by researchers. Distinctively, artificial intelligence (AI)-based techniques, in particular Fuzz*y *Logic (FL) one, have been emerged as a powerful complement to conventional methods. Design objectives that are mathematically hard to express can be incorporated into a Fuzzy Logic Controller (FLC) using simple linguistic terms. The merit of FLC relies on its ability to express the amount of ambiguity in human reasoning. When the mathematical model of a process does not exist or exists with uncertainties, FLC has proven to be one of the best alternatives to move with unknown process. Even when the process model is well-known, there may still be parameter variation issues and power electronic systems, which are known to be often approximately defined. The purpose of this paper is to demonstrate that a great efficiency improvement of motor drive can be achieved and hence a significant amount of energy can be saved by adjusting the flux level according to the applied load of an induction motor by using an on-line fuzzy logic optimization controller based on a vector control scheme. An extensive simulation results highlight and confirm the efficiency improvement with the proposed algorithm.

**KEYWORDS:**

- Induction Motor Drive
- Indirect Field Oriented Control (IFOC)
- Efficiency Enhancement
- Losses Minimization
- Optimization
- Fuzzy Logic

**SOFTWARE:** MATLAB/SIMULINK

**BLOCK DIAGRAM:**

** **

Fig.1. Block diagram of the optimization system

** ****EXPECTED SIMULATION RESULTS:**

Fig.2. Motor Performances Comparison

Fig.3. Motor efficiency evolution with motor load

** ****CONCLUSION:**

This paper aims to improve the induction motor drive efficiency that leads to a significant amount of energy saving. This efficiency enhancement is carried out by adjusting the flux level depending on the applied load of an induction motor by using an on-line fuzzy logic optimization controller based on a vector control scheme. A series of the induction motor drive performances are obtained with a variable load under this proposed algorithm. The application of the proposed algorithm yields to a series of simulation performances of the induction motor drive with a variable load. They present the IM drive efficiency evolution with a certain load profile with the suggested losses minimization strategy based on fuzzy control and the conventional field oriented control. The comparison between these two control schemes reveals that the achieved results are of a great interest. Indeed, the fuzzy control contributes with a great deal to the efficiency improvement for all operating speeds particularly in light load region. This contribution conducts to a paramount energy saving and hence to environment protection.

**REFERENCES:**

[1] I. Boldea, A. Nasser, The Induction Machine Design Handbook, CRC Press Inc; 2nd Revised Edition, 2009.

[2] Jinchuan. Li and all, “A new Optimization Method on Vector Control of Induction Motors”, *Electric Machines and Drives, 2005 IEEE International Conference, *15-18 May 2005, pp.1995-2001.

[3] H. Sepahv and, Sh. Ferhangi, “Enhancing Performance of a Fuzzy Efficiency Optimizer for Induction Motor Drives”, *Power Electronics Specialists Conference*, 2006. PESC ’06. 37th IEEE, 18-22 June.2006, pp.1-5.

[4] Branko Blanusa and all, “An Improved Search Based Algorithm for Efficiency Optimization in the Induction Motor Drives”*, XLII Konferencija- za ETRAN*, Hercy-Novi, 2003.

[5] D. S. Kirischen, D. W. Novoty and T. A. Lipo, “Optimal Efficiency Control of an Induction Motor Drive”, *IEEE Transaction on Energy Conversion, *Vol. EC-2, N° 1, March 1987, pp.70-76.