Induction Motor Performance Improvement using Super Twisting SMC and Twelve Sector DTC

Induction motor (IM) direct torque control (DTC) is prone to a number of weaknesses, including uncertainty, external disturbances, and non-linear dynamics. Hysteresis controllers are used in the inner loops of this control method, whereas traditional proportional-integral (PI) controllers are used in the outer loop. A high-performance torque and speed system is consequently needed to assure a stable and reliable command that can tolerate such unsettled effects. This paper treats the design of a robust sensorless twelve-sector DTC of a three-phase IM. The speed controller is conceived based on high-order super-twisting sliding mode control with integral action (iSTSMC). The goal is to decrease the flux, torque, the current ripples that constitute the major conventional DTC drawbacks. The phase current ripples have been effectively reduced from 76.92% to 45.30% with a difference of 31.62%. A robust adaptive flux and speed observer-based fuzzy logic mechanism are inserted to get rid of the mechanical sensor. Satisfactory results have been got through simulations in MATLAB/Simulink under load disturbance. In comparison to a conventional six-sector DTC, the suggested technique has a higher performance and lower distortion rate

Hybrid fuel cell-supercapacitor system: modeling and energy management using Proteus

The increasing adoption of electric vehicles (EVs) presents a promising solution for achieving sustainable transportation and reducing carbon emissions. To keep pace with technological advancements in the vehicular industry, this paper proposes the development of a hybrid energy storage system (HESS) and an energy management strategy (EMS) for EVs, implemented using Proteus Spice Ver 8. The HESS consists of a proton exchange membrane fuel cell (PEMFC) as the primary source and a supercapacitor (SC) as the secondary source. The EMS, integrated into an electronic board based on the STM32, utilizes a low-pass filter algorithm to distribute energy between the sources. The accuracy of the proposed PEMFC and SC models is validated by comparing Proteus simulation results with experimental tests conducted on the Bahia didactic bench and Maxwell SC bench, respectively. To optimize energy efficiency, simulations of the HESS system involve adjusting the hybridization rate through changes in the cutoff frequency. The analysis compares the state-of-charge (SOC) of the SC and the voltage efficiency of the fuel cell (FC), across different frequencies to optimize overall system performance. The results highlight that the chosen strategy satisfies the energy demand while preserving the FC’s dynamic performance and optimizing its utilization to the maximum

Behavioral modeling of knitted shape memory membrane

International audienceProgrammable matter is a system of elements (e.g., smart matters, modular robots, …) that is programmed via user input or autonomous sensing to form a certain shape, by altering its physical characteristics. This paper presents a programmable and reusable device to be used, for example in 4D prototyping and Haptics, using the shapeshifting abilities of smart materials such as shape memory alloys to exhibit a certain behavior controlled by stimulus (heat energy). More precisely, these materials can be programmed and integrated into devices or systems to function according to suitable configurations and conditions (e.g., shape making), via stimuli control as programming means, and wherein the behavior can be modelized using appropriate equations. The programmable device presented in this paper is a shape memory membrane, that makes 3D forms out of a knitted architecture to match a target model, using the shape memory effect. Simulation results using COMSOL are presented and analyzed to model the thermo-mechanical behavior and establish the device’s programming model

Programmable smart articulated interface

International audienceThe programmable matter has paved the way for the emergence of new paradigms in the fields of computer science, design, Haptics, and material science. Several kinetic-based approaches have been developed to represent an object via surface deformation using a set of patterned actuators. Therefore, a loss of shape is noticed in the physical rendering as the actuation is applied in a single direction. This work considers a deformable interface having a chained architecture, in which smart materials such as shape memory alloy are used as a controllable hinge mechanism allowing to perform bidirectional self-folding capabilities. Such an interface can render 3D models through two main operations: NURBS slicing and segment fitting operations. More precisely, models are downscaled to match the configuration of the interface (chains × hinges per a chain), then angles are exported and replicated by the controllable shape memory effect of shape memory alloy using the Joule effect. Unlike the existing architectures, this approach affords to render a physical model with a low digital to physical conversion loss by means of its geometric complexity (e.g., cavities, lateral shape variation). The proposed approach has been modeled and validated through numerical simulation using COMSOL Multiphysics® software

Statistical tools and approaches to validate analytical methods: methodology and practical examples★

The analyst needs to know whether the result of measurement can be accepted with confidence or, on the contrary, rejected because it is wrong. It is essential, also, to know whether an analysis method is suitable for the intended use. Likewise, it is more important for the researcher to know if he can trust a new developed method and what are the criteria to respect to ensure its validity. The statistical tools allow us to address all these points. The experimental protocol applied in this work is based on a common methodology, inspired by regulatory guidelines regarding statistical data analysis in analytical method validation, to optimize the number of assays and satisfy the study of validation criteria. In order to better understand the statistical analysis of raw data, practical examples are treated for quantify: an active ingredient in pharmaceutical drugs, a heavy metal in fishery products, and a drug in seizures

Statistical tools and approaches to validate analytical methods: methodology and practical examples

The analyst needs to know whether the result of measurement can be accepted with confidence or, on the contrary, rejected because it is wrong. It is essential, also, to know whether an analysis method is suitable for the intended use. Likewise, it is more important for the researcher to know if he can trust a new developed method and what are the criteria to respect to ensure its validity. The statistical tools allow us to address all these points. The experimental protocol applied in this work is based on a common methodology, inspired by regulatory guidelines regarding statistical data analysis in analytical method validation, to optimize the number of assays and satisfy the study of validation criteria. In order to better understand the statistical analysis of raw data, practical examples are treated for quantify: an active ingredient in pharmaceutical drugs, a heavy metal in fishery products, and a drug in seizures