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Summary: This paper presents a novel three‐phase hybrid multilevel inverter (TPHMLI) designed for grid‐connected solar photovoltaic (SPV) systems. The TPHMLI combines series‐connected bridge topologies of half and full circuits to generate 11 stages of line load voltages, reducing the need for DC sources. It also introduces an improved pulse width modulation (PWM) approach, addressing computational challenges and high‐frequency triggering issues. Practical validation in a laboratory setting demonstrates the MLI's functionality and effectiveness. Furthermore, the advanced MLI topology successfully addresses design issues in grid‐integrated SPV structures, including power quality, efficiency, and reliability. It excels in managing reactive power and fault obstructive capabilities. Extensive simulations using MATLAB/Simulink confirm its superior performance, making it a promising solution for power conditioning units in grid‐connected solar PV systems. This research contributes to clean and sustainable energy conversion technologies, enhancing power quality and cost‐effectiveness, with significant potential for practical applications in the renewable energy sector. [ABSTRACT FROM AUTHOR]

The paper deals with the dynamics of a resistance spot welding system. At the core of this system is a transformer, which is powered on the primary side by a pulse-width modulated inverter and has a full-wave output rectifier on the secondary side that provides a direct welding current. The entire system is nonlinear, due to magnetic hysteresis and electronics. The electronics prevent the current from flowing in all parts of the welding transformer at separate time intervals during the voltage supply period; therefore, not all the parameters affect the dynamic of currents and voltages all the time so the system is also time-variant. To design a high-performance welding system and to predict the maximum possible welding current at a specific load, it is necessary to know the welding and primary currents. The leakage inductances of the system can reduce the maximum welding current significantly at higher frequencies and the same load. There are several methods to determine these currents, each with its drawbacks. Measurements are time-consuming, using professional software is expensive and requires time to learn and free open-source software has many limitations and does not guarantee the correctness of the results. The article presents a new, fourth option—a theoretical derivation of analytical expressions that facilitate straightforward and rapid calculation of the welding and primary currents of the resistance spot welding system with symmetrical secondary branches. The derivation of the mathematical expressions is based on the equivalent circuits that describe the system in different operating states. The results of the numerical simulations confirmed the derived expressions completely. [ABSTRACT FROM AUTHOR]

The permanent magnet synchronous motor (PMSM) avoids commutation-related torque ripples and produces smooth torque. Its great handling capacity and better efficiency make it an excellent choice for high-demand applications. A typical PM motor drive fed with pulse width-modulated voltages may cause the motor insulation to break down if rapid voltages (dv/dt) occur across the motor terminals. Applying variable voltage with low dv/dt and implementing multiple inverter topology can solve this issue. Multilevel converters have minimal switching losses, better power quality and the ability to operate at both fundamental and higher switching frequencies. In this study, a three phase stacked multilevel inverter-based FOC driven PMSM drive design is proposed. Here, the neutral point is a capacitor intermediate point on DC side, where current is naturally balanced throughout a switching cycle. This makes it possible to use downstream batteries and even lower voltage equipment, greatly increasing efficiency, improved performance and smother control at low speed. Therefore, direct-battery-driven electric vehicles will be able to use this. A 33 level inverter-based PMSM drive was used to implement the FOC, and the simulation results were used to validate it. The Matlab/Simulink tool is used to simulate the entire system. [ABSTRACT FROM AUTHOR]

The permanent magnet synchronous motor (PMSM) avoids commutation-related torque ripples and produces smooth torque. Its great handling capacity and better efficiency make it an excellent choice for high-demand applications. A typical PM motor drive fed with pulse width-modulated voltages may cause the motor insulation to break down if rapid voltages (dv/dt) occur across the motor terminals. Applying variable voltage with low dv/dt and implementing multiple inverter topology can solve this issue. Multilevel converters have minimal switching losses, better power quality and the ability to operate at both fundamental and higher switching frequencies. In this study, a three phase stacked multilevel inverter-based FOC driven PMSM drive design is proposed. Here, the neutral point is a capacitor intermediate point on DC side, where current is naturally balanced throughout a switching cycle. This makes it possible to use downstream batteries and even lower voltage equipment, greatly increasing efficiency, improved performance and smother control at low speed. Therefore, direct-battery-driven electric vehicles will be able to use this. A 33 level inverter-based PMSM drive was used to implement the FOC, and the simulation results were used to validate it. The Matlab/Simulink tool is used to simulate the entire system.

Smart and precision agriculture seeks to boost the efficiency of operations and crop yield by using modern technology. Modern tools such as sensors, imagery cameras, and deep learning enable farmers to identify and control weeds, pests, and diseases in real-time. A robotic platform can carry these modern types of equipment and achieve the mentioned objectives precisely. Automatic and accurate navigation of this autonomous robot in agricultural fields is essential for performing these precision tasks. An agricultural robotic platform was designed and developed for row crop fields. The robot navigation system comprises two main components: a vision-based row detection system for path tracking and a motion controller system. The vision-based guidance system processes acquired image data from a tilted camera in front of the robot to identify the crop row's position. The Hough transform method was used to determine the position of the crop rows. Using the resultant guidance line equations, the motion controller directs the robot to move automatically between rows without harming the crops. Differential speed steering allows both wheels on the robot to rotate at different speeds. The steering system improved the robot position error by controlling both powered wheel speeds. To move the robot among the crop rows, it generates the wheel speed difference command. The robotic platform effectively followed the rows of sugar beets at a velocity of 0.5 m/s, exhibiting an average lateral offset of 12 mm and a standard deviation of 22 mm. [ABSTRACT FROM AUTHOR]

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The paper proposes a novel speed sensor‐less stator flux‐oriented vector control of dual‐stator induction generator suitable for high‐power applications in grid‐tied wind energy conversion system. In this control strategy, the magnitude and angle of the flux are directly estimated by the measured stator voltages and currents. As the voltage and current sensors are placed on the stationery stator part, therefore, the proposed control strategy does not affect the robustness of the machine compared to the conventional rotor flux‐oriented vector control where the sensors need to be mounted on the rotating part of the machine. Moreover, the proposed speed encoder‐less stator flux‐oriented vector control eliminates the use of speed encoder, thereby reducing the cost and eliminating the error caused due to faulty speed measurement by the speed encoder of the overall system. The performance of the novel speed sensor‐less stator flux‐oriented vector control scheme has been verified by simulation and then experimentally on a 2 hp, 415 V, 50 Hz, three‐phase dual‐stator induction generator drive. The control strategy was implemented through dSPACE 1104 DAC card. From the simulated and the experimental results, it is evident that the proposed control strategy reflects improved performance w.r.t. conventional rotor flux‐oriented vector control. [ABSTRACT FROM AUTHOR]

Light emitting diodes (LEDs) play an essential role in lighting, and green earth activities because of their high efficiency, longevity, and reduction of carbon dioxide emissions during illumination. However, the brightness level of LED light sources must be adjusted appropriately for the backlight source or illumination; therefore, pulse amplitude modulation (PWM) is a commonly used method of LED control. This article experimentally investigated human interaction with the visual comfort effect of the light obtained using different PWM frequencies on an object in a sensor-based intelligent lighting system. Critical light frequencies are vital for the eye to distinguish light stimuli according to time. Histograms of the object were created according to the light frequency, and the results are discussed. The eye's response to light frequencies changing over time is important for visual comfort, and examining light frequencies in the range of 25–250 Hz was sufficient to conclude the study. It has been experimentally shown that light frequencies around 160 Hz, and above this value provide visual comfort. [ABSTRACT FROM AUTHOR]

The most recent advancement in switched-capacitor boost inverters for high-frequency ac systems and solar PV utilization is their reduced component count. SC-based multilevel inverters (MLIs) are the ideal solution for PV applications since they have a larger voltage gain and a sensorless mechanism for self-voltage balancing. This article presents a boost inverter scheme for higher-level output that involves input voltage boosting. The proposed topology can be reconfigured to produce 9 and 13 levels of output voltage with alternative topologies and a voltage gain of four or three, respectively. Twelve semiconductor devices, three capacitors, and a single input source are used to achieve the voltage gain/higher levels. The proposed boost topology has been contrasted with a number of related topologies and empirically validated using a number of experimental findings.

In thin‐film transistors (TFTs), issues such as interface states may lead to unstable device performance and complex physical phenomena, such as frequency dispersion effects. This paper establishes a three‐terminal TFT compact model capable of replicating capacitance dispersion phenomena and directly applying to SPICE circuit simulations. The model decomposes the transistor's capacitance frequency response into the superposition of responses from different electronic states. The different electronic states are emulated by parallel branches, each composed of voltage‐dependent capacitance and resistance connected in series. The Powell algorithm is employed to achieve automatic parameter optimization. The model is generic for TFTs and successfully replicates capacitance dispersion phenomena in carbon nanotube (CNT) and indium‐gallium‐zinc‐oxide (IGZO) thin‐film transistors. This work provides insights to the circuit behavior of display driver circuits at high frequencies and improving circuit reliability. [ABSTRACT FROM AUTHOR]

Recently, multiphase drives have emerged as a notable alternative for three-phase drives in several domains, including electric marine propulsion, locomotive traction, and high-power industrial applications where fault tolerance and high reliability are required. This study uses a graphical approach to develop a new carrier-based Pulse-Width Modulation (PWM) that reduces the root-mean-square value of the output current ripple in two-level multiphase inverters with an odd number of phases. The optimization process calculates the optimal common-mode voltage for each switching period. Numerical models and experiments with five- and seven-phase inverters demonstrate the effectiveness of the developed PWM technique, which can reduce the number of commutations while obtaining the lowest output current ripple.

This article presents a 6.78 MHz single-stage wireless power transfer (WPT) receiver (RX) using 0X/1X regulating rectifier with improved voltage mode (VM) delay compensation for implantable medical devices (IMDs). The regulation of 0X/1X modes is achieved through pulse width modulation (PWM), with the frequency set at 1/16 of the carrier clock to ensure circuit stability and enhance power conversion efficiency (PCE) under light loads. VM delay compensation has the advantage of power consumption. However, the traditional VM on-delay compensation may become ineffective because a large voltage pulse will occur on the RX side input when the circuit delays increase. Therefore, an improved VM on-delay compensation method is proposed. Coarse compensation for on-delays can be achieved by reusing the control signal generated from off-delay compensation loop, as off-delay compensation processes will not be influenced by on-delay compensation processes. It allows the on-delay compensation loop to function normally and finely compensate for on-delays. The proposed rectifier is designed in $0.18\mu $ m CMOS process. It can achieve output voltage management of 1.8V. Comparing with other regulating rectifier, the proposed rectifier has a fast transient response of $14~\mu $ s and a small chip area of 0.91 mm2. The simulation results indicate that this rectifier can attain high PCE of 84.6% in light load ( $500\Omega $ ) and peak PCE of 93.5% in heavy load ( $50\Omega $ ). The high voltage conversion ratio (VCR) of over 93% is also achieved under the large circuit delays.

Single-stage differential mode inverters (DMI) have been extensively utilized in three-phase grid-connected systems due to several advantages, such as few semiconductor devices resulting from their simple and modular configuration. Nevertheless, the modulation and control strategy require further enhancement to enable more efficient power conversion across various operations. Therefore, this paper introduces a detailed analytical model of the SEPIC-DMI, leading to the development of a hybrid discontinuous modulation scheme pulse width modulation (DMS-PWM), which incorporates zero voltage switching (ZVS), denoted as Hybrid DMS-ZVS-PWM approach. In the proposed strategy, the duty cycle of SEPIC-DMI is zero for one-third of the grid frequency cycle, which leads to minimizing conduction and switching power losses. Moreover, the voltage stress on the components is significantly reduced due to DMS-PWM. For ZVS, a simplified active-clamp circuit is proposed and designated using a single switch and two small capacitors. The proposed active-clamp circuit is integrated into the SEPIC-DMI to verify SEPIC power switches’ ZVS and zero current switching (ZCS). The ZVS/ZCS improves the inverter efficiency by major minimization in power losses. The mathematical derivations and performance measurements (simulation and experiment) are provided to show the superiority of the proposed hybrid DMS-ZVS-PWM method. The peak efficiency of SEPIC-DMI is enhanced from 90% to 94%, and the voltage stress is curtailed in all components with 13%.

The human intervention free bidirectional efficient energy exchange between the grid and Electric Vehicles (EVs) relies on effective bidirectional power flow control in Wireless Power Transfer (WPT) system. This essential bidirectional control feature enables the grid to charge the EV’s battery and, during surplus energy periods, allows the EV to feed power back to the grid. This capability facilitates the implementation of Vehicle-to-Grid (V2G) functionalities. Implementing this bidirectional flow requires sophisticated modulation techniques to ensure seamless power transfer and optimize overall efficiency. In comparison to pulse width modulation, pulse density modulation (PDM) proves more effective in minimizing switching losses in the converter. PDM efficiently manages the amplitude of high-frequency pulses generated by the inverter and converter systems for WPT applications. However, the PDM techniques are not effectively investigated in the bidirectional wireless power transfer system (BWPT). In this paper, Fuzzy Logic Controlled Pulse Density Modulation (FLC-PDM) approach for the BWPT is proposed for the first time. This approach uses dual side pulse density control for high-frequency converters with the fuzzy rule base to adjust the pulse density and duty ratio based on the load demand. The proposed approach aiming to optimize efficiency across diverse loads and regulate the output voltage and provides effective control approach for the BWPT system. This method ensures constant switching frequency output voltage regulation and delicate shifting operation for high-frequency converter switches, requiring no additional components. The circuit simulations and hardware prototype testing are performed for the 3.7 kW power rating and 85 kHz operating frequency to validate the proposed FLC-PDM approach for the BWPT circuit and yielded an efficiency over 93% across diverse load resistances and pulse densities.

As power demand from electric vehicles and digital loads increases, the use of direct current power supplies is increasing. As a result, the application of microgrid utilizing various distributed power systems is expanding. As demand power and load capacity increase, parallel operation of multiple power converters is required to increase the capacity of power converters used in distributed power systems. Among parallel control methods, load sharing through communication has a significant effect on control performance due to communication speed and reliability. This paper proposes an instantaneous load-sharing parallel control method using a high-speed communication method that can transmit data necessary for load-sharing every control cycle. The proposed communication method uses enhanced PWM and capture communication using a DMA module to compensate for the shortcomings of the existing method using PWM and capture functions. Whenever the master voltage controller is executed, the data required for parallel operation is updated, and by transmitting this data to the slave, instantaneous load sharing control with high speed response is possible. We explain the communication and system architecture of the proposed method and present the communication protocol specifications and design. The performance and validity of the proposed instantaneous load sharing parallel control method were verified through simulation and experiments.

Implementing dimming control in visible light communication (VLC) systems often involves a trade-off that reduces data rates. To address this, we propose a hybrid visible light (VL)/Infrared (IR) communication scheme that leverages pulse amplitude modulation (PAM) symbols in both VL and IR spectra, alternating them within pulse width modulation (PWM) “ON” and “OFF” slots. By efficiently using PWM “OFF” slots, the achievable data rate drop due to dimming is mitigated without affecting illumination. To ensure synchronization during the switch between VL and IR links, we design real-time dimming control state machines at both ends of the link, enhancing link stability. Additionally, we develop an adaptive hybrid frame structure that dynamically adjusts the length of transmitted information as the duty cycle continuously changes, ensuring uninterrupted communication. Experimental results from implementation using field-programmable gate arrays (FPGA) demonstrate real-time transmission under precise full-range dimming control, dynamically ranging from 1 to 0 with a resolution of 0.0053, maintaining a consistent 10 Mb/s data rate at bit error rates (BERs) lower than 3.4 × 10−4 and 20 Mb/s at BERs lower than 7.0 × 10−3 within a link range of 0.53 m without light concentration at the transmitter. Compared to baseline VLC, our system achieves a 100% data rate improvement at a duty cycle of 0.5, and supports stable data transmission even in low-light conditions.

The paper deals with the dynamics of a resistance spot welding system. At the core of this system is a transformer, which is powered on the primary side by a pulse-width modulated inverter and has a full-wave output rectifier on the secondary side that provides a direct welding current. The entire system is nonlinear, due to magnetic hysteresis and electronics. The electronics prevent the current from flowing in all parts of the welding transformer at separate time intervals during the voltage supply period; therefore, not all the parameters affect the dynamic of currents and voltages all the time so the system is also time-variant. To design a high-performance welding system and to predict the maximum possible welding current at a specific load, it is necessary to know the welding and primary currents. The leakage inductances of the system can reduce the maximum welding current significantly at higher frequencies and the same load. There are several methods to determine these currents, each with its drawbacks. Measurements are time-consuming, using professional software is expensive and requires time to learn and free open-source software has many limitations and does not guarantee the correctness of the results. The article presents a new, fourth option—a theoretical derivation of analytical expressions that facilitate straightforward and rapid calculation of the welding and primary currents of the resistance spot welding system with symmetrical secondary branches. The derivation of the mathematical expressions is based on the equivalent circuits that describe the system in different operating states. The results of the numerical simulations confirmed the derived expressions completely.

The comparative performance analysis of conventional PI controller and Fuzzy Logic Controller for a switched mode converter application. Switched mode converters needs to regulate its output voltage to lower voltage and must quickly respond to fast load and line variations or transients to keep the output voltage within a limited range. The design of high performance linear proportional integral controller for switched mode converter presents series of challenges due to nonlinear nature of the plant process. Fuzzy logic controller is mostly used in variety of industrial applications including use in domestic appliances and main tool of operation of fuzzy logic controller is membership function. By using the MATLAB and Simulation we compare the characteristics of the linear proportional integral controller and nonlinear fuzzy logic controller with switched mode converter and also which gives the desired results. The main comparison for Proportional Integral controller (PI) and Fuzzy logic controller (FLC) is to get the pure Direct current (DC) without any fluctuations for sensitive applications. The Switched Mode Converter with both the PI controller and Fuzzy logic controller is implemented and output characteristics are analyzed and compared. The switched mode converters are efficient in power conversion, taking a main voltage AC input and converting it down to a low voltage DC output. AC-DC switched-mode converters are better used. It is used for the external desktop power supply laptop, set-top box, and the wall plug-in charger for smartphones and computers. [ABSTRACT FROM AUTHOR]

To ensure that a variable-rate spray (VRS) system can perform unmanned aerial spray in accordance with a prescription map at different flight speeds, we examine in this paper such significant factors as the response time of the VRS system and the pressure fluctuation of the nozzle during the variable-rate spraying process. The VRS system uses a lag compensation algorithm (LCA) to counteract the droplet deposition position lag caused by the system response delay. In addition, pulse width modulated solenoid valves are used for controlling the flowrates of the nozzles on the variablerate spray system, and a mathematical model was constructed for the spray rate (L min-1) and the relative proportion of time (duty cycle) each solenoid valve is open. The pressure drop and solenoid valve response time at different duty cycles (50~90%) were measured by indoor experiments. Meanwhile, the lag distance (LD), spray accuracy, and droplet deposition characteristics of the VRS system were tested by conducting outdoor experiments at different flight speeds (4m s-1, 5m s-1, 6m s-1). The results show that LCA can effectively reduce the LD. The LD values of the VRS system with LCA ranged from -0.27 to 0.78m with an average value of 0.32m, while without LCA, the LD values increased to 3.5~4.3m with an average value of 3.87m. The overall spray position accuracy was in the range of 91.56~97.32%. Furthermore, the spray coverage and deposition density, determined using water sensitive paper, were used to evaluate the spray application performance taking into account the spray volume applied. The VRS system can provide the most suitable spray volumes for insecticide and fungicide plant protection products. Based on a prescription map, the optimized VRS system can achieve accurate pesticide spraying as well as desirable spray coverage and deposition density. [ABSTRACT FROM AUTHOR]

Due to environmental concerns, electric vehicles (EVs) are becoming more and more common in automobiles. Since electrical vehicles rely on rechargeable batteries to manage their power supply, therefore, it’s important to have a reliable, efficient, and affordable battery charger that can consistently deliver the required output for the specific EV’s battery. A DC-DC converter with a pulse width modulation (PWM) based Sliding-Mode Voltage controller is presented in this paper to help reduce charging time by achieving the required output voltage, high current density, and negligible overshoot for the specified lithium-ion battery system. Both ideal and nonideal conditions are used to analyse the proposed converter. The performance of dc and ac side inductors has been designed and analysed to ensure their efficiency and affordability. According to the findings, the proposed converter is able to maintain a power factor of approximately 90% with less total harmonic distortion both of which are ideal for the high-current density load. [ABSTRACT FROM AUTHOR]

In this paper, the Preisach model for magnetic hysteresis of grain-oriented silicon steel under PWM excitation is improved. First, an improved Preisach model for the magnetic hysteresis of grain-oriented silicon steel under PWM excitation is proposed. Second, the experimental platform for grain-oriented silicon steel sheets under PWM excitation is established. Finally, by comparative analysis, it is concluded that the error of the improved model is far less than that of the classical model (the error here refers to the discrepancy between experimental results and theoretical model predictions). The improved model is 1.4% to 9% more accurate than the classical model. A more accurate model can provide more accurate material parameters for the calculation of the magnetic field in the transformer core, which is of great significance to the production and design of the transformer. [ABSTRACT FROM AUTHOR]

Vibration, in most cases, is an undesirable phenomenon in electro-mechanical systems. The adverse effects of vibration in a system are noise, loss of energy, compromise on comfort, and reduced life span of mechanical systems. The current study focuses on vibration damping of a Flexible Cantilever beam (FCB) by utilizing a differential type of electromagnetic actuator. The electromagnetic forces of both actuators are controlled by Pulse Width Modulation (PWM) using a current controller designed in the lab. The electromagnets are mounted above and below the FCB by maintaining a distance along the same vertical axis. The non-contact active vibration attenuation study is carried out by varying the PWM values of upper and lower electromagnets to produce different electromagnetic forces. The current research work compares different combinations of forces on upper and lower electromagnets experimentally and, based on the analysis, provides the best combination of forces on both actuators to damp the vibrations as swiftly as possible. The study is divided into three cases where case I study the vibration damping with the same PWM on both electromagnets; in case II and case III, one of the electromagnets has fixed PWM while the PWM on other electromagnet is varied. [ABSTRACT FROM AUTHOR]

Traditional current and voltage strategies proposed for the single-phase rectifier with pulse width modulation (PWM) used in the AC charging system for electric vehicles, have a large response time and the percentage of total harmonic distortion (THD) of the line current is more than 2%, which causes a reduction of the power factor (PF). The present paper focuses on the robust sliding mode current–voltage control (SMCVC) design for the single-phase rectifier with PWM. This SMCVC strategy used the grid current directly without any rotating coordinate transformations and reduced the complexity computational of the implementation algorithm and allows to satisfy the following desired performances, low THD of the input current and the PF is around one in a faster response time. In this paper, the proposed control strategy is compared and verified with proportional integral (PI) control and proportional integral sliding mode current control (PI-SMCC) by Matlab/Simulink. At the end of this paper, simulation examples are given to illustrate our approach and to show that our proposed method provides very good results with respect to some literature results. [ABSTRACT FROM AUTHOR]

This paper presents an in-depth exploration of a single-phase multilevel cascaded H5 (CH5) transformerless inverter employing both phase-shifted PWM (PS-PWM) and level-shifted PWM (LS-PWM) methodologies. A comparative analysis is conducted with the conventional multilevel inverter (MLI) topologies, specifically the cascaded H-bridge (CHB) and H5 inverter configurations. The investigation delves into the impact of modulation index variations, load fluctuations, and modulation methods on the inverter's operational performance.While switches in the CHB-MLI operate continuously at the carrier frequency state using PS-PWM and LS-PWM methods, the CH5-MLI exhibits a unique behavior with some switches toggling at high frequency, while others synchronize with the grid frequency. The CH5-MLI topology demonstrates efficiency improvements and a reduction in total harmonic distortion (THD). Notably, employing the LS-PWM method yields more significant efficiency enhancements and THD reduction compared to the PS-PWM method. To analyze power loss characteristics under diverse operating conditions, the PLECS simulation environment is leveraged for calculating conduction and switching losses.The application of phase-shifted and level-shifted carrier-based pulse width modulation strategies to high and low-frequency switching switches results in minimized output harmonics, elevated operator safety, and enhanced overall reliability and efficiency. This work contributes significantly to the field by offering a detailed exploration of the CH5-MLI topology's dynamic behavior, modulation strategies, and their collective impact on performance metrics such as efficiency, THD, and power losses.

Selective harmonic elimination pulse-width modulation (SHE-PWM) method has been widely used in various industrial multilevel converters befitting from low switching frequencies and precise elimination of low-order harmonics. Most of existing studies focus on accelerating calculation of switching angles or optimizing predictive neural networks. However, these offline methods cannot dynamically deal with the errors introduced by nonuniform dc sources of multilevel converters or biased placements of switching angles. This paper proposes an online adaptive SHE (OA-SHE) algorithm to compensate these errors. Errors caused by nonideal dc (NID) sources and leading-lagging placements (LLPs) are analyzed in detail. The error of output waveform is comprehensive result of NID sources and LLPs. By introducing feedback, the output waveform accuracy of multilevel converters can be increased greatly. Realization of the particle swarm optimization (PSO) with an embedded control system is presented to acquire good real-time performance. With the OA-SHE method, the value of particles has been higher than the initial value. High order harmonics, including 1st, 5th, 7th, 11th, and 13th components, are suppressed by the low-pass filter. Comparing to existing studies, this online algorithm does not need detailed model parameters and can be directly applied to practical applications achieving multi-objective optimization. Finally, both simulations and experiments are carried out to verify the effectiveness of this algorithm.

Summary: The modular multilevel converter (MMC) is a novel prospective multilevel converter topology for high‐voltage or high‐power applications. This paper presents the 3‐ Φ model integrated into a linear model in transient analysis and the design of current controller for MMC. This paper analyzes the control interactions of MMC on nearby turbine generator. The eigenvalue analysis is used to evaluate the impact of different controller modes of MMC. The impact of converter control with nonlinear switches is analyzed through the transient simulation. The eigenvalue analysis and controller design are carried out on a linear model, and the transient simulation analysis is performed on both the D‐Q model and a three‐phase model of MMC using MATLAB‐Simulink. The results show that the transient simulation of three‐phase model on the proposed approach is consistent with the transient simulation of D‐Q model. Also, the transient simulation results show a satisfactory response with the current controller parameters of the MMC at various operating cases. To validate the results of MATLAB‐Simulink model, the proposed system is implemented in hardware‐in‐the‐loop (HIL) simulation with an integrated subsystem built in two real‐time simulators. The subsystem of mathematical model is implemented in dSPACE, and the subsystem of 3‐ Φ MMC with controller is implemented in Typhoon. The HIL simulation results show a satisfactory response and consistent with MATLAB‐Simulink model results. [ABSTRACT FROM AUTHOR]

This paper works on the modelling of solar PV with series parallel connection of the strings for the composite climate location and the detailed study has been done on the gate signal of the chopper used for boosting with three different conditions. As the climate conditions are very important factor for the installation of the project to fulfill the captive requirements, a study has also been done with the help of climate consultant software so that the radiations capacity and potential to develop the energy is with in its maximum output capacity. In the next phase an inverter has also been connected for the conversion into single phase AC output for the testing of the model for the usage in the load or grid. Various methods for the control of the booster has been analyzed and considered. Simulation is done on a Matlab software and the result is analyzed. [ABSTRACT FROM AUTHOR]

The development of microcontroller technology has been implemented in the robotics industry, particularly in performing tasks that are risky for living beings, especially humans. In this context, a wheeled smart car robot can automatically extinguish fires. The fire extinguishing system is taken over by the robot's system when fire or heat is detected, and the robot's controller activates the extinguishing system, spraying water at the fire point. The ESP 32 CAM microcontroller serves as the processing and controlling unit, handling data and displaying real-time camera images to ensure accurate fire extinguishing. Additionally, a mecanum wheel drive mechanism is added to enhance the robot's movement flexibility. [ABSTRACT FROM AUTHOR]