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This work experimentally addresses damage calibration of an unmanned aerial vehicle in operational condition. A wide range of damage level and types are simulated and controlled by an electric motor via pulse width modulation in this regard. The measurement is carried out via established protocols of using a piezo-patch on one of the 8 arms, utilising the vibration sensitivity and flexibility of the arms, demonstrating repeatability of such protocol. Subsequently, recurrence analysis on the voltage time series data is performed for detection of damage. Quantifiers of damage extent are then created for the full range of damage conditions, including the extreme case of complete loss of power. Experimental baseline condition for no damage condition is also established in this regard. Both diagonal-line and vertical-line based indicators from recurrence analysis are sensitive to the quantitative estimates of damage levels and a statistical test of significance analysis confirms that it is possible to automate distinguishing the levels of damage. The damage quantifiers proposed in this paper are useful for rapid monitoring of unmanned aerial vehicle operations of connection. [ABSTRACT FROM AUTHOR]

Cardiac monitoring systems in Internet of Things (IoT) healthcare, reliant on limited battery and computational capacity, need efficient local processing and wireless transmission for comprehensive analysis. Due to the power-intensive wireless transmission in IoT devices, ECG signal compression is essential to minimize data transfer. This paper presents a real-time, low-complexity algorithm for compressing electrocardiogram (ECG) signals. The algorithm uses just nine arithmetic operations per ECG sample point, generating a hybrid Pulse Width Modulation (PWM) signal storable in a compact 4-bit resolution format. Despite its simplicity, it performs comparably to existing methods in terms of Percentage Root-Mean-Square Difference (PRD) and space-saving while significantly reducing complexity and maintaining robustness against signal noise. It achieves an average Bit Compression Ratio (BCR) of 4 and space savings of 90.4% for ECG signals in the MIT-BIH database, with a PRD of 0.33% and a Quality Score (QS) of 12. The reconstructed signal shows no adverse effects on QRS complex detection and heart rate variability, preserving both the signal amplitude and periodicity. This efficient method for transferring ECG data from wearable devices enables real-time cardiac activity monitoring with reduced data storage requirements. Its versatility suggests potential broader applications, extending to compression of various signal types beyond ECG. [ABSTRACT FROM AUTHOR]

The paper proposes a nonlinear controller called dual super-twisting sliding mode command (DSTSMC) for controlling and regulating the rotor side converter (RSC) of multi-rotor wind power systems that use doubly-fed induction generators. It was proposed that this controller be developed as an alternative to the direct power control (DPC), which makes use of a pulse width modulation (PWM) strategy to regulate the RSC's functioning. Overcoming the power/current quality issue with the proposed technique (DPC-DSTSMC-PWM) is characterized by great robustness and excellent performance. The designed strategy was contrasted with the standard method of control and other methods already in use. So, the unique proposed control strategy's robustness, performance, efficiency, and efficacy in enhancing system characteristics were tested and validated in Matlab/Simulink. In both tests, the proposed method resulted in significant improvements, reducing active power ripples by 83.33%, 57.14%, and 48.57% in the proposed tests. When compared with the traditional regulation method, the reduction rates of reactive power ripples are 64.06%, 52.47%, and 68.7% in the tests. However, in contrast to the conventional method, the proposed tests showed a decrease of between 72.46%, 50%, and 76.22% in the value of total harmonic distortion (THD) of the provided currents. These ratios show how effective the proposed plan is in ameliorating and enhancing aspects of the energy system. [ABSTRACT FROM AUTHOR]

In PMSM drive systems, sensor-less vector control of permanent magnet synchronous motors (PMSM) over the entire speed range poses considerable challenges. Through the design and simulation of the sensor-less vector control system of PMSM, this paper proposes a novel method for sensor-less field-oriented control (FOC) for PMSM applications. To solve this intricate control problem, FOC combines gh-reference frame space vector pulse width modulation (SVPWM) with cubature Kalman filter (CKF). Implementing CKF to estimate rotor position and speed accurately provides the basis for this sensor-less control technique. Furthermore, the integrated control system using gh-SVPWM aims to reduce controller board computing resources utilization while minimizing torque ripple and stator current harmonic distortion. The effectiveness of CKF-based sensor-less FOC integrated with gh-SVPWM is verified in various operating environments using an extensive simulation and experimental framework, confirming its potential to enhance PMSM driving performance and efficiency in different applications. [ABSTRACT FROM AUTHOR]

A multi-level inverter (MLI) is essential to improve the performance and efficiency of the inverter, which is widely accepted for high-power and high-voltage applications. Its performance is significantly superior due to higher DC link voltages, lower electromagnetic interference, and lower harmonic distortion. However, it has some drawbacks, like voltage balancing problems, complex pulse width modulation methods, and an increased number of components. This paper investigated the selective elimination of harmonics in optimization-based cascaded H-bridge (CHB) 27-level inverters for hybrid renewable energy sources. This method uses hybrid renewable energy sources such as solar photovoltaics, wind, and tidal turbines with single maximum power point tracking (MPPT). A single MPPT with a Dwarf Mungo optimization (DMO) algorithm is implemented to obtain high performance from hybrid sources simultaneously. The proposed inverter comprises ten semiconductor switches connected to three direct current (DC) sources. The Osprey optimization algorithm (OOA) is used in the 27-level inverter to calculate the switching angles for selective harmonic elimination of pulse width modulation (SHE-PWM). The proposed approach is used on a Simulink platform to assess performance, and its efficacy is demonstrated by contrasting it with an existing approach. The simulation obtained 1.98% THD by using OOA with SHE-PWM. The total cost obtained by the proposed method is 40.03$, and the computational time for DMO and OOA is 1 s and 1.2 s at the 100th iteration. The experimental validation is established using a dSPACE RTI1104 controller to validate the proposed method. The experimental results obtained 1.99% of harmonics with the same output voltage as the simulation. [ABSTRACT FROM AUTHOR]

This paper presents a new controller based on the Lyapunov theory used in a stand-alone photovoltaic (PV) system. The proposed system does not include a pulse width modulation (PWM) controller unlike a traditional one. The quadratic converter including one controllable switch is modeled as a switching system which allows us to propose a switching rule that can be used to control the converter. This part assures the stability of the operating point at any desired voltage value. To determine the operating point that allows to extract a maximum of power from the system, a double-mode variable step size maximum power point tracking algorithm is included in the controller. The proposed method is a hybridization between the well-known perturb and observe (P &O) algorithm and an operation at a fixed voltage value during fast solar irradiance changes. The performances of the global controller are tested through simulation using Simulink/MATLABTM\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$^{\textrm{TM}}$$\end{document}. It is compared to a classical system with PWM and P &O controllers. The result shows that the proposed controller can harvest up to 15%\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$15 \%$$\end{document} more energy from the PV panel in case of fast solar irradiance changes without significantly increasing the implementation cost. [ABSTRACT FROM AUTHOR]

To improve the total efficiency of a dual-bridge series resonance converter, a pulse width modulation plus phase-shifted modulation with voltage balance condition is proposed for a hybrid dual-bridge series resonance converter. The control scheme is unified for the whole operating condition and with simple calculation. By employing the proposed voltage balance control, the equivalent unity voltage gain operation can always be achieved, while a simplified two degrees of freedom control can be easily formed. Wide soft-switching range and reduced tank current can be ensured by the pulse width modulation in active hybrid bridge, and power level is adjusted by the phase-shifted modulation. In addition, a magnetizing current compensation method is also employed to improve the soft-switching performance of low voltage side four MOSFETs. The effectiveness of the proposed control is verified by the experimental results. [ABSTRACT FROM AUTHOR]