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In Laser Power Bed Fusion (LPBF), the process and operating parameters influence the mechanical and geometrical characteristics of the manufactured parts. Therefore, the optimization and control of these parameters are mandatory to improve the quality of the produced parts. During manufacturing, the process parameters are usually constant whatever the part size or the built layer. With such settings, the manufacturing process may lead to an inhomogeneous thermal behavior and locally overheating areas, impacting the part quality. The aim of this study is to take advantage of an analytical thermal model to modulate the laser power upstream of manufacturing.

The approach takes place in two steps: the first step consists in calculating the preheating temperature at the considered point and the second one determines the power modulation of the laser to reach the desired temperature at this point.

Numerical investigations on several use cases show the effectiveness of the method to control the overheated areas and to homogenize the simulated temperature distribution.

The specificity of this model lies in its ability to directly calculate the amount of energy to be supplied without any iterative calculation. Furthermore, to be as close as possible to the technology used on LPBF machines, the kinematic behavior of the scanning head and the laser response time are also integrated into the calculation.

To evaluate assumptions relevance of an analytical heat flow model used in indirect measurement of heat capacity and thermal conductivity by the modulated calorimetry technique.

Assumptions are tested by comparing analytical prediction to numerical simulation results.

This study validates the analytical model for a solid sample.

This research only focuses on solid samples.

This paper allows a broader study on the relevance of modulated calorimetry on liquid samples.

These implementations not only generate excessive voltage levels to enhance the quality of power but also include a detailed investigating of the various modulation methods and control schemes for multilevel inverter (MLI) topologies. Reduced harmonic modulation technology is used to produce 11-level output voltage with the production of renewable energy applications. The simulation is done in the MATLAB/Simulink for 11-level symmetric MLI and is correlated with the conventional inverter design.

This paper is focused on investigating the different types of asymmetric, symmetric and hybrid topologies and control methods used for the modular multilevel inverter (MMI) operation. Classical MLI configurations are affected by performance issues such as poor power quality, uneconomic structure and low efficiency.

The variations in both carrier and reference signals and their performance are analyzed for the proposed inverter topologies. The simulation result compares unipolar and bipolar pulse-width modulation (PWM) techniques with total harmonic distortion (THD) results. The solar-fed 11-level MMI is controlled using various modulation strategies, which are connected to marine emergency lighting loads. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by using SPARTAN 3A field programmable gate array (FPGA) board and the least harmonics are obtained by improving the power quality.

The simulation result compares unipolar and bipolar PWM techniques with THD results. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by a SPARTAN 3A field programmable gate array (FPGA) board, and the power quality is improved to achieve the lowest harmonics possible.

The purpose of this paper is to propose a DC-port voltage balance strategy realizing it by logic combination modulation (LCM). This voltage balance strategy is brief and high efficient, which can be used in many power electronic devices adopting the cascaded H-bridge rectifier (CHBR) such as power electronic transformer (PET).

The CHBR is typically as a core component in the power electronic devices to implement the voltage or current conversion. The modulation method presented here is aiming to solve the voltage imbalance problem occurred in the CHBR with more stable work station and higher reliability in ordinary operating conditions. In particular, by changing the switch states smoothly and quickly, the DC-port voltage can be controlled as the ideal value even one of the modules in CHBR is facing the load-removed problem.

By using the voltage balance strategy of LCM, the problem of voltage imbalance occurring in three-phase cascaded rectifiers has been solved properly. With the lower modulation depth, the efficiency of the strategy is shown to be better and stronger. The strategy can work reliably and quickly no matter facing the problem as load-removed change or the ordinary operating conditions.

The limitation of the proposed DC-port voltage balance strategy is calculated and proved, in a three-module CHBR, the LCM could balance the DC-port voltage while one module facing the load-removed situation under 0.83 modulation depth.

This paper provides a useful and particular voltage balance strategy which can be used in the topology of three-phase cascaded rectifier. The value of the strategy is that a brief and reliable voltage balance method in the power electronic devices can be achieved. What is more, facing the problem, such as load-removed, in outport, the strategy can response quickly with no switch jump and switch frequency rising.

The purpose of this paper is to find out the use of compressive sensing (CS) algorithm for wireless sensor networks (WSNs). As energy-efficient algorithms are required for WSNs, CS is very much useful as less than 25 per cent of the entire input data alone is required to be transmitted, and reconstruction at the receiver with this reduced data set is of good quality. But, the usefulness of the algorithm with suitable modulation schemes is not analyzed so far in the literature. Hence, this work concentrated on the algorithm performance with different modulation schemes and different channel conditions.

Compressive sensing encoding is performed by using suitable transform on the input signal. Here, DCT and DWT are used to generate the sparse signal. Random measurement matrix is used to generate the compressed output, which is reconstructed using the Basis Pursuit (BP) method. Also, an analysis for the energy-efficient modulation scheme is performed by modulating the compressed output using QPSK/BPSK/QAM and transmitted by considering the Gaussian and Rayleigh Channels. Energy required per bit transmission is modeled and computed for different schemes.

Simulation result shows that the use of CS algorithm for data compression tremendously reduces the number of transmission bits and, hence, enhances the transmission and bandwidth efficiency in WSN. Results show that DWT is a much suitable transform to be used for sparse measurement generation. In comparison with DCT, DWT is computationally simple and takes very less time, which is expected in real-time application. The reconstruction result shows that about 25 per cent of the data sample is sufficient to recover the original image, perhaps which is the most surprising result. An extensive analysis of various modulation schemes based on the energy model shows that QPSK is in the AWGN channel, and QAM modulation in the Rayleigh channel is a much suitable modulation scheme to be used in WSN for further reduction of energy consumption.

Compressive sensing is recently gaining importance for quantization, compression and noise removal in images. In this paper, this technique was used along with modulation schemes to analyze the suitability of the algorithm for WSN.

Induction heating applications aided by power electronic control have become very attractive in the recent past. For cooking applications, power electronics circuits are very suitable to feed power to multi loads with an appropriate control technique. The purpose of this paper is to develop a three leg inverter to feed power to three loads simultaneously and independently.

Pulse density modulation control technique is used to control the output power independently with constant switching frequency.

Multi-load handling converter with independent power control is achieved with reduced number of switching devices (two switches/per load) with simple control strategy.

The proposed system is simulated in MATLAB/Simulink, and the thermal analysis is carried out in COMSOL multi-physics software. The hardware realisation is performed for a 1 kW prototype with 20 kHz switching frequency and 10 kHz pulse density modulation frequency. PIC16F877A microcontroller is used to validate the experimental results for various values of control signals (D_PDM). The simulation and experimental results are in good agreement and validates the developed system.

The design issues on network architecture and modulation scheme that can be used to implement reliable MIL‐STD‐1773 avionics optical fiber data buses are discussed. Both single‐star and multi‐star architectures are presented to such optical fiber data buses. Several network configurations based on passive and/or active coupling components are also considered, and they are compared in terms of system complexity and reliability. Moreover, three modulation schemes are presented, i.e. partial trilevel Manchester II bi‐phase coding, extended Manchester II bi‐phase coding with beginning‐stopping flags, and pseudo‐four‐ary pulse width modulation, respectively. Their use can feasibly solve the problem associated with fast identification of correct operation states of an active transmitter at the output of optical receivers.

This paper aims to propose a bidirectional hidden converter (BHC)-based three-phase DC–AC conversion for energy storage application. BHC is the new concept to vary an energy storage device voltage into wide range. Hidden converter power loss and power rating are reduced by using zero-sequence injection-based carrier-based pulse-width modulation (CBPWM) strategy.

By using this control strategy, a BHC processes only little amount of power during double-stage conversion, mostly during direct or single-stage conversion of the three-phase three-port converter (TPTPC) only processing the maximum power.

TPTPC consists of two sets of positive group switches for inversion process, one set of switches is regular inverter switches called vertical positive group switches, and the second set is anti-series switches, which are horizontally connected for direct or single-stage conversion.

Characteristics, principles and implementations of proposed DC–AC 3Ø conversion system and its PWM strategy are analyzed. Through experimental outputs, the effectiveness and viability of the proposed solutions are validated.

The purpose of this paper is to provide a theoretical platform for studying the characteristic of random carrier frequency (RCF) modulation and analyze the related parameters in terms of electromagnetic interference (EMI) suppressing.

In this paper, the expression of the amplitude of switching voltage power spectra under the RCF mode is presented. According to the expression, the effectiveness of related parameters on EMI mitigation is discussed. Theoretical predictions are confirmed with a closed‐loop boost converter which power is 7.5 W and nominal switching frequency is 200 KHz. Finally, special attention has been paid to output voltage ripple.

Under RCF scheme, with increasing of random degree, the spectrum of switching voltage is dispersed, so the power spectrum density amplitude of switching voltage falls, and then the level of EMI is lowered. This theory shows that the voltage power spectrum density attains maximum when d=0.5, so in the spread spectrum modulation, the duty cycle of 0.5 should be avoided in terms of conducted EMI mitigation.

The analytical expression of switching voltage power spectra under the RCF mode is presented, providing a theoretical platform for the related research. The selection of duty cycle has effect on EMI level is put forward for the first time. Voltage ripple is discussed in close‐loop circuit.

The purpose of this paper is to find the optimum inverter type as the solder joint reliability point of view.

In this paper, finite element model(ing) simulations supported with power cycling aging experiments were used to demonstrate the best inverter type as the solder joint reliability point of view.

It was found that inverter types highly affect the solder joint health during its nominal operating.

The authors confirm the originality of this paper.