Anup Kumar Panda

This letter proposes a novel quadruple boost nine-level inverter (QB-NLI) and an optimized switching pattern using fuzzy logic controller. The suggested method simplifies the traditional approach by removing the conventional logic gate circuit design. The pulse signal generator and lookup table are both derived using a fuzzy logic pulse generator. Fuzzy logic controller (FLC) and Controlled membership functions (MFs) rules open numerous prospects for generating pulses based on the input as modulation index. The suggested technique is examined on the proposed QB-NLI topology using the selective harmonic elimination PWM method. MFs are created based on averaging Newton Rapson and quantizer firing angles for diverse modulation index (mi) values. The proposed QB-NLI structure comprises ten switches with one dc-voltage source and two capacitors. The proposed structure’s circuit description, modes of operation, proper component selection, and a new fuzzy-based switching scheme are presented. Further, a discussion about the comparative analysis of the proposed switching technique with other switching techniques concerning THD and RMS voltages is presented. In addition to the simulation results, experimental tests are conducted under various load conditions on the built-in hardware prototype to evaluate the proposed QB-NLI structure and switching technique.

This paper provides an interval type-2 fuzzy-based direct torque control (IT2FDTC) of the induction motor drive (IMD) in which a hybrid duty ratio control (HDRC) technique is used to activate a two-level inverter. Moreover, it is implemented with the help of DSPACE-1104 controller in a real-time application using a 2HP induction motor and compared its overall performance with a conventional proportional-integral direct torque control (CPIDTC) using SVM technique. The IT2FDTC can be provided less torque and flux ripples with a faster dynamic performance of IMD over a CPIDTC. This due to the fact that a three-dimensional Mamdani type-2 fuzzy controller along with the centroid method is used in the defuzzification process for the proposed control method. The proposed method of study effectively controls the gains of PI and HDRC. Also, HDRC has a total of five possible duty ratios in which two novel duty ratios are introduced including two clamping and one SVM duty ratios to further improve the current/flux/torque harmonic profile performance of IMD than CPIDTC.

This paper provides an interval type-2 fuzzy-based direct torque control (IT2FDTC) of the induction motor drive (IMD) in which the space vector modulation (SVM) technique is used here to activate a five-level diode clamped inverter (FDCI). Moreover, it is implemented with the help of the DSPACE-1103 controller in a real-time application using 2HP induction motor and is compared its overall performance with a conventional proportional-integral direct torque control (CPIDTC). In IT2FDTC, all four capacitor voltages of FDCI based on minimum energy principle are balanced well and settled back quickly with fewer peak overshoots than CPIDTC during various operational conditions. In addition, it can provide lesser torque and flux ripples with a fast dynamic performance of IMD over a CPIDTC. A three-dimensional Mamdani type-2 fuzzy controller along with the centroid method is used in IT2FDTC. Hence, the proposed method of study not only controls the gains of PI effectively, but also controls the duty ratios of a modulating wave to further improve the dynamic performance and current profile of IMD.

In this paper, a unusual switching technique is implemented using a fuzzy logic approach. The proposed technique simplifies the conventional method by eliminating the traditional logic gate design. The fuzzy logic pulse generator acts as a look-up table as well as a pulse generator. Based on the modulation index as input, controlled membership functions (MFs) and rules of the fuzzy logic controller (FLC) opens various possibilities in producing pulses directly. The proposed technique is evaluated on the cascaded multilevel inverter with symmetric and asymmetric operations using selective harmonic elimination pulse width modulation (SHE-PWM). MFs are designed based on the pre-calculated firing conditions for different modulation index values. The hardware verification is carried out to support the proposed switching technique.

The torque ripple, current fluctuation and variable switching frequency of conventional hysteresis current controller (CHCC) under different loading condition and motion variation is inevitable, which demands effective implementation of the existing current controller by which it will be possible to get rid of these limitations. This paper presents enhancement in performance of a vector controlled based Interior Permanent Magnet Synchronous Motor (IPMSM) drive system by using an adaptive hysteresis current controller (AHCC). This controller minimizes torque ripple, current error and is capable of providing nearly constant switching frequency by modifying its bandwidth according to the changes in the system parameter or when the system is subjected to any kind of disturbances and load variation. Initially the study is carried out in MATLAB-Simulink environment and then the test result is experimentally validated through hardware implementation with the help of DSP TMS320F2812 which provides a complete digital control system with high effectiveness and fast computational skill.

This research article proposes the shunt active filter (SHAF) control strategies (p–q and Id–Iq), which are used to improve the power quality of the electrical network by mitigating the harmonics with the help of Type-2 fuzzy logic controller (Type-2 FLC) different membership functions (MFs). Three-phase reference current waveforms generated by proposed scheme are tracked by the three-phase voltage source converter in a hysteresis band control scheme. The performance of the proposed control strategies has been evaluated in terms of harmonic mitigation and DC link voltage regulation under various source conditions. In order to maintain DC link voltage constant and to generate the compensating reference currents, we have developed Type-2 FLC with different fuzzy MFs (trapezoidal, triangular and Gaussian). The SHAF with proposed Type-2 FLC using Gaussian MF is able to eliminate the uncertainty in the system and SHAF gains outstanding compensation abilities. The detailed real-time results using real-time digital simulator are presented to support the feasibility of proposed control strategies.

This letter presents a single phase cascaded transformer multilevel inverter with modified carrier based level shift sinusoidal pulse width modulation (LS-SPWM) technique. The developed topology has two bridges with individual low frequency transformers. The bridges can generate quasi-square waveform and pulse width modulated (PWM) waveform independently and energized the two transformers whose secondary terminals are cascaded to attain nineteen level output voltage waveform across the load. The anticipated configuration has the least number of components to reduce the cost and enhance the reliability of the converter for medium power applications with inbuilt isolation. Furthermore, this paper presents the most common LS-SPWM technique with a new carrier to enhance the fundamental magnitude and shifts the dominant harmonics into three times of the traditional strategy for the same modulation indices. The performance of the proposed topology is validated with experimental results.

A new hybrid control technique called gradient descent back propagation (GDBP)‐based for a three phase two‐level distribution static compensator (DSTATCOM) to perform the functions such as harmonic mitigation, power factor correction under reactive loads, which further reduces the DC link voltage across the self‐supported capacitor of voltage source converter (VSC). The weighted value of fundamental active and reactive components of load currents are extracted using the proposed control technique to generate the reference source currents. Furthermore, these currents are used to trigger the VSC of the DSTATCOM. The effectiveness of this control technique is demonstrated through simulation using MATLAB/SIMULINK and sim power system tool boxes. The real‐time implementation of DSTATCOM is also realised by real‐time digital simulator. These results reveal the robustness of the proposed DSTATCOM as it is showing outstanding harmonic compensation capabilities under the various loading conditions and keeping the total harmonics distortion of the source current well <5%, the limit imposed by IEEE‐519 standard.