Improved Direct Torque Control of Induction Motor for Torque Ripple Minimization

Abstract

A new direct torque control (DTC) method of an induction motor (IM) which minimizes torque ripple <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\left ({T_{ripp} }\right)$ </tex-math></inline-formula> while preserving all the conventional DTC advantages is presented in this paper. Large <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$T_{ripp}$ </tex-math></inline-formula> and current ripple are the main drawbacks of the conventional DTC. To address this problem, this paper gives a qualitative analysis of the main <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$T_{ripp}$ </tex-math></inline-formula> sources of the conventional DTC. A novel strategy to reduce <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$T_{ripp}$ </tex-math></inline-formula> in the constant <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$T$ </tex-math></inline-formula> and in the field weakening (FW) regions is proposed. The performance of the proposed method is evaluated and compared with a recently published method that aims for the same goals that are pursued in this paper, as well as with the conventional DTC. The analysis has been carried out on the basis of the results obtained by theoretical analysis and hardware implementation.