This study presents the hybrid direct torque control (HDTC) method for medium voltage-range induction motor (IM) drive. The control method comprising the torque control by rotor-reference frame quadrature-axis current instead-of conventional DTC and speed control similar as in space-vector-modulation (SVM)-DTC is proposed. Hence the scheme is referred as HDTC. A carrier-based space-vector-modulation controlled five-level diode-clamped multilevel inverter with proposed control scheme is providing promising-step towards performance enhancement of IM drive in respect of torque ripple contents and steady-state performance over wide speed-range. The effectiveness of the proposed control scheme is confirmed by comparison with DTC in matlab-simulink. A prototype is fabricated for three-phase, 3-HP IM. A 32-bit fixed-point DSP-based control algorithm is developed for DTC and the proposed control scheme. Experimental results show qualitative improvement in performance in terms of reduction in torque ripple by 30%, fast dynamic response even at low speed and improvement in steady state characteristics.

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The term smart grid (SG) has been used by many government bodies and researchers to refer to the new trend in the power industry of modernizing and automating the existing power system. SGs must utilize assets optimally by making use of the information, like equipment capacity, voltage drop, radial network structure, minimizing investment and operating costs, minimizing energy loss and reliability indices, and so on. One way to achieve this is to re-route or reconfigure distribution systems (DSs). Distribution systems are reconfigured to choose a switching combination of branches of the system that optimize certain performance parameters of the power supply, while satisfying some specified constraints. In this paper, a blended biased and unbiased weightage (BBUW) multiple attribute decision-making (MADM) method is proposed for finding the compromised best configuration and compared it with other decision-making methods, such as the weighted sum method (WSM), weighted product method (WPM), and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. The BBUW method is implemented for two distribution systems, and the result obtained shows a good co-relationship between BBUW and other decision-making methods. Further weights obtained from the BBUW method are used for the WSM, WPM and TOPSIS methods for decision making. Examples of the distribution system are worked out in this paper to demonstrate the validity and effectiveness of the method.

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