**5. Modern strategies of DTC**

#### **5.1 Fuzzy logic control (FLC)**

The limits of the torque hysteresis band are controlled by FLC. It entails a minimization of the torque ripples as well as an improvement of the dynamic performances of IM. The FLC selects the optimum bandwidth of the torque hysteresis in real time [9].

The fuzzified parameters such as torque error, stator flux errors, and stator flux angle are the input to FLC. The switching state of the inverter is a crisp value obtained as an output from the FLC [11].

A detailed classification and comparison of DTC strategies like SMC, FLC and ANN in terms of performance parameters of induction machine were discussed in [20].

The PI controller and FLC algorithm have been implemented for the three-phase induction motor and it is found that the proposed FLC scheme is better than the conventional DTC control with PI control in [21].

The effective DTC improvements are achieved by Fuzzy logic controller thereby the ripples in torque and flux are reduced, consequently secondary problems for the motor such as heating, mechanical vibration, aging are also rectified. The merits of the conventional are also preserved [22].

### **5.2 Artificial neural network (ANN)**

A multilayer ANN allows to replace both hysteresis comparators and the selection table in classical DTC.

The ANN offers the following merit over classical DTC.

i. The complexity of the controller is reduced;


For electric vehicle applications, the FLC and ANN based monitoring systems for the DTC controlled induction motor drive was implemented to detect a very small change in performance parameters [23].

Tref reference motor torque

*DOI: http://dx.doi.org/10.5772/intechopen.94225*

*Torque Ripple Reduction in DTC Induction Motor Drive*

Lls stator leakage inductance

**A.1 Appendix 1: parameters of 3 phase squirrel cage induction motor**

RATED POWER 5.4 HP RATED VOLTAGE 400 V RATED SPEED 1430 RPM RATED TORQUE 26.7 Nm RATED CURRENT 8.5 A STATOR RESISTANCE 1.405 Ω ROTOR RESISTANCE 1.395 Ω STATOR INDUCTANCE Ls 0.005839H ROTOR INDUCTANCE Lr 0.005839H MAGNETIC FLUX 0.1827 weber NO. OF POLES 4 MOMENT OF INERTIA 0.0131 kgm<sup>2</sup> FRICTION FACTOR 0.002985 Nms/rad

\*, Maheswaran Mockaisamy<sup>2</sup>

1 Department of Electrical and Electronics Engineering, PSG Institute of Technology and Applied Research, Coimbatore, Tamil Nadu, India

2 Department of Mechatronics Engineering, Nehru Institute of Engineering and

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

θ<sup>r</sup> rotor position ω<sup>m</sup> rotor speed L self-inductance

Rs stator resistance ia, ib, ic three phase currents Va, Vb, Vc three phase voltage

**A. Appendices**

**Author details**

**157**

Adhavan Balashanmugham<sup>1</sup>

and Sathiyanathan Murugesan<sup>1</sup>

Technology, Coimbatore, India

provided the original work is properly cited.

\*Address all correspondence to: adhav14@gmail.com
