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For high-frequency switching applications, silicon carbide (SiC) devices are more suitable than silicon-based devices, which is conducive to improving the efficiency and power density of power electronic equipment. However, as the switching frequency increases, the influence of parasitic parameters on the switching characteristics of devices becomes increasingly apparent. When SiC metal-oxide-semiconductor field-effect transistors (MOSFETs) are applied in bridge circuits, the crosstalk problem easily occurs with the complementary conduction of upper and lower transistors, which seriously limits the promotion of SiC MOSFETs. However, the existing crosstalk suppression drive circuit tends to increase the switching loss, switching delay, and control complexity; therefore, a gate drive with crosstalk suppression capability is proposed. In this paper, the gate drive has two features: a negative voltage to shut down the SiC MOSFET; and an adjustment of the gate-source equivalent impedance. To accomplish this goal, the mechanism of crosstalk voltage generation is analyzed. Furthermore, the operation principle of the gate drive is analyzed, and the parameters of the gate drive are designed. Eventually, the proposed gate drive is verified by an LTspice simulation and experimental platform. The results prove that the gate drive can suppress the crosstalk voltage without affecting the switching speed. [ABSTRACT FROM AUTHOR]

This article outlines the relevance of building online telemetry systems for online monitoring of the technical conditions of rolling mill equipment. Electromechanical systems of the horizontal stand of the plate Mill 5000 are described, when operating in harsh conditions caused by the shock loading when workpieces enter the stand. It is noted that dynamic torque overloads, exceeding the rated motor torque by many-fold, cause the fatigue failure of spindle joints and breakage of rolls. In this regard, the development and implementation of systems for monitoring the elastic torque on spindles are extremely urgent. This issue has long been studied, but the references provide no information on the building principles and hardware composition of such systems. The use of strain gauges connected according to a balanced bridge circuit to measure the elastic torque is justified. This paper's contribution is the proposed modular principle for building a telemetry monitoring system based on the analysis of known techniques for measuring and transmitting diagnostic data. The developed system structure is provided and the concept of data transfer and processing are explained. This article suggests the inductive power supply of a measuring unit mounted on a shaft without the use of batteries. A hardware structure was developed to be applied in a system for measuring, transmitting, and visualizing signals proportional to the elastic torque, manufactured on the basis of data measuring instruments by leading companies. The specifics of placement and connection of strain gauges are considered. The hardware providing a wireless power supply to the signal encoder and digital data transfer between the transmitter and receiver is described. The results of implementing the system on Mill 5000 are provided. The installation of a telemetry ring and a receiving head for the inductive power supply and data reception is shown. An experimental assessment of the elastic torques occurring when workpieces enter the cage was obtained by implementing a drive control algorithm which provided biting in the drive acceleration mode. The reliability of measuring the elastic torque with an error not exceeding ±5% and the reduction of dynamic loads on the spindle by 1.3–1.5 times due to the elimination of impacts from closing angular gaps in spindle joints was confirmed. This increases the service life of mechanical equipment and reduces the cost of eliminating the accident aftermath. The prospect of modifying the developed system into a cyber-physical system for monitoring the rolling mill's mechatronic equipment conditions is shown. [ABSTRACT FROM AUTHOR]

The article presents the issues related to load-power sharing in direct-current grid and a novel control method has advantages over known solutions. Unlike many similar-sounding papers, this article shows an attempt at creating fully controllable non-isolated system that allows for load-power sharing between a permanent magnet alternator equipped with machine-side converter (MSC) and a dual active bridge (DAB) tied to batteries or supercapacitor. The current-based load-power sharing is an essential feature of parallel-connected direct-current generators, and all types of voltage sources, in this way are contributing power to the system. To keep the optimal efficiency of the alternator, the rotational speed changes rely on proper mapping of the driving combustion engine. System components include a self-excited synchronous generator (SESG), operating at variable shaft speed, as well as batteries and supercapacitors that provide electricity for sudden electrical-load changes on the distribution grid. The core of the presented system is in a power-distribution method that consists of a programmed-controller structure allowing precise current distribution. A novelty of the proposed method is the use of a cascaded system of current and DC voltage regulators that allows for precise power-distribution control. In contrast with previously presented solutions, the proposed system allows for fast and accurate control of currents, loading parallel-connected DC voltage sources for wide-range generator speed changes. In the presented solution, both converters have been equipped with Schottky diodes, preventing the flow of equalizing currents between closed transistors in the parallel mode of operation. An experimental test-stand of the described system is presented with its theoretical basis and experimental results. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper proposes a novel control method to achieve the true unity power factor for a single‐phase boost rectifier. Firstly, the phase difference between the voltage and current on the AC side is calculated by the heterodyne method. Secondly, this phase difference is fed into an integral regulator to get a phase shift angle. Finally, by using the heterodyne method once again, the AC side current is phase‐shifted and used as the modulation signal for the single‐phase full bridge rectifier circuit and ultimately yields a unity power factor. The experimental results verify the effectiveness and feasibility of this strategy. [ABSTRACT FROM AUTHOR]

Stable control and accurate sensing are necessary for the safe operation of soft robots, and flexible sensors that can follow the flexible movements of soft robots are needed. In this paper, flexible bending sensors are embedded in a rib-reinforced vacuum-driven actuator with no risk of rupture, considering the application of flexible sensors to human cooperative work and wearable devices. The bending sensor is a bridge circuit with conductive silicone rubber (CSR) for variable resistance. The CSR bridge sensor consists of four CSRs that capture deformation and a circuit with a conductive coating spray printed on a laminated sheet. The sensor value is the output voltage divided by the input voltage, and the effects of the drift and input voltage variations are canceled out. The bending sensor embedded in the silicone actuator has a linear relationship, and the rib-reinforced vacuum driven actuator provides angle PID control for continuously changing reference inputs by feeding back sensor estimated angle. Furthermore, contact detection was established by using the pressure estimated from the CSR bridge sensor and the pressure sensor error as the threshold. The algorithm provides reliable contact detection and force estimation with actuator response thresholds and anti-chattering. [ABSTRACT FROM AUTHOR]

The circulating current in the non-isolated power supply composed of an AC current converter and a DC current converter affects the normal operation of the power supply for electrolytic hydrogen production characteristics testing. This paper proposes a novel topology without circulating current by using half bridge circuit. First, the circulating current in the traditional non-isolated circuit with a full bridge circuit is analyzed, and the loop of the circulating current is obtained. The influence of the DC side voltage of AC current converter on the circulating current is analyzed. Then, through the equivalent circuit, the circulating current loop has been removed and a novel topology is presented. The circulating current in the proposed topology can be eliminated. The proposed analysis results and topology have been verified through simulation and experimental results. • A power supply composed of two paralleled converters has a DC circulating current. • The circulating current is determined by the DC voltage of the full bridge circuit. • A proposed half bridge circuit can effectively suppress the DC circulating current. • The circulating current suppression is not affected by the load dynamic process. [ABSTRACT FROM AUTHOR]

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A novel method for loads acquisition to the shock absorber upper strut mount by two three-component column-type sensor and spring sensor is proposed in this research. The strain gauge configuration and the decoupling balanced bridge circuit of the proposed column-type sensor are designed and analyzed theoretically. In order to verify the theoretical analysis of the measurement bridge output, simulations, and experimental tests were performed. It was shown that the measurement bridge outputs from the theoretical analysis, simulations and experiments were basically consistent. Then, the calibration of the designed sensors was conducted according to the SAE J2570 standard specification requirements, which were then employed to measure the lateral and impact force of the shock absorber upper strut mount. Taking the loads acquired on pothole road as an example, the signal of each sensor was described and the lateral and impact force loads on the upper strut mount is finally calculated. [ABSTRACT FROM AUTHOR]

In this paper, the electromagnetic performance of variable flux memory (VFM) machines with series-magnetic-circuit is investigated and compared for different rotor topologies. Based on a V-type VFM machine, five topologies with different interior permanent magnet (IPM) arrangements are evolved and optimized under same constrains. Based on two-dimensional (2-D) finite element (FE) method, their electromagnetic performance at magnetization and demagnetization states is evaluated. It reveals that the iron bridge and rotor lamination region between constant PM (CPM) and variable PM (VPM) play an important role in torque density and flux regulation (FR) capabilities. Besides, the global efficiency can be improved in VFM machines by adjusting magnetization state (MS) under different operating conditions.

This work presents the molybdenum di-sulphide three-phase bridge rectifier integrated circuit utilizing the novel self-switching diode. The self-switching diode has a planar architecture having I-V behavior similar to an ideal diode. The structure of SSD is utilized to design single phase and three phase rectifiers. The performance in terms of rectification efficiency, total harmonic distortion, ripple factor and cut-off frequency has been evaluated and compared for both single and three phase SSDBR. The three-phase self-switching diode bridge rectifier (3P-SSDBR) has a cut-off frequency of ∼400 MHz with minimum total harmonic distortion (THD) and ripple factor (RF) of 4.73% and 0.59, respectively. While, the single phase self-switching diode bridge rectifier (1P-SSDBR) has a cut-off frequency of ∼300 MHz with minimum total harmonic distortion (THD) and ripple factor (RF) of 47.86% and 1.94, respectively. Further, to validate the obtained results, the simulation models have been calibrated with experimental and theoretical findings. [ABSTRACT FROM AUTHOR]

The research work proposes a Gallium Nitride (GaN) based dual active bridge (DAB) converter for electric vehicle (EV) charging applications. The wide bandgap semiconductor device, GaN is implemented in the DAB topology of an Isolated Bidirectional DC-DC converter (IBDC). GaN-based DC-DC converters lead to higher efficiency, smaller size, faster charging, and reduced heat generation improving the overall performance of the EV charging system. The performance characteristics of GaN based DAB converter is analyzed both in simulation and hardware for EV charging application. The same analysis is extended to a Si based DAB converter and comparative results are presented. A 14.25 kW GaN based DAB and 10.5 kW Si based DAB is designed and evaluated using LTspice XVII software and a scaled-down prototype of 0.612 kW GaN based DAB and 0.25 kW Si based DAB is presented for experimental validation. Result analysis under similar operating conditions indicated an improvement of 36% more output power transfer on the GaN based DAB over the traditional Si based DAB. The developed prototype showcased improved levels of power, voltage, and current under same operating conditions. The power transmission in the developed DAB based IBDC topology is controlled using the Single-Phase-Shift (SPS) control strategy. [ABSTRACT FROM AUTHOR]