Energetic consumption improvement in induction motors with possible mechatronics applications

ABSTRACT

This document proposes an energetic output improvement of electric drives for induction motors. This modification pointing toward a better energetic output (improving the efficiency) according to the application, and can be made in the most common control algorithms as the Flux Oriented Control (FOC) and the Direct Torque Control (DTC). An on-line flux variation method is proposed depending of the load requirements, based on the measured of the consumed power and the computation of the optimal flux by an algorithm of seeking of the minimum losses; so that the output of optimal flux computed by the algorithm is the reference input for one well known control scheme (FOC, DTC). The experimental results show that the proposed controller ensures both, a good speed control and smooth torque response with current shapes with low THD, when these are compared with the conventional DTC scheme. Experimental results for a 1.1 kW induction motor are presented and analyzed using a dSpace system with DS1103 controller board based on the digital processor Texas Instruments TMS320F240. The obtained results showed that the proposed control scheme is able to obtain a high performance in some mechatronic applications (robotics, e.g.) because is able of a perfect tracking for a reference position with bounded current and torque.

KEYWORDS:

• Direct torque control
• efficiency improvement
• energetic output
• induction motor
• position control