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Background and Objectives: The H-bridge (HB) driver design with high efficiency is one of the most challenging issues in power systems that drive AC/DC loads. HB driver circuit based upon complementary MOSFET type used as a driving system of DC motor, power converters, and battery charger for electrical vehicles. In Driving DC motors, dead-time (DT) generation has been considered a major factor such as preventive power line short-circuits (shoot-through) over high and low-side MOSFETs. In this paper, the HB driver is designed for linear actuators with consideration for the prevention of shoot-through. Methods: The propagation delay of logic gates are used to postpone the arrival gate drive signal for high/low side MOSFETs resulting in short circuit elimination on the DC source. Results: As mentioned, logic gates' propagation delay by their values causes interruption between the high and low-side power switches gate drive signal resulting in shoot-through elimination. Although the existence of DT influences the performance of the rotational speed and output torque of a DC motor by increasing the distortion and pulse interval, Linear actuators due to low-velocity linear motion do not require the PWM control, therefore DT has no substantial effect on driver performance. Conclusion: Simulation and experimental results validate the method proposed in this paper. According to the specifications of the circuit designed in this paper, for loads that do not need rotational speed control, logic gates with proper propagation delay can be chosen to eliminate short circuits in complementary MOS switches without requiring DT compensation methods. [ABSTRACT FROM AUTHOR]

This paper presents a method that enables a small car to reach its destination in an indoor environment using ultrawideband technology. For this purpose, we used four anchors and one tag. The tag can move because it is fixed on the car. The anchors and the tag are DWM1001 modules. The configuration of the five DW1001 modules is performed through a smartphone application provided by the manufacturer. The car has been built by us. The controller of the car is a Raspberry Pi microcomputer which controls the driver of the car DC motors by generating PWM signals. In addition, Raspberry Pi communicates with the tag by the UART interface. Thus, our goal was to control the car to reach a certain destination (xd, yd) requested by the user via Wi-Fi. Because the car hosts the tag, it continuously updates its position according to the information received from the four anchors. We implemented two scenarios, considering the initial (x, y) position of the car. In the first scenario, which is simpler, the car moved to its destination either along the x-axis or along the y-axis. In the second scenario, the car moves along one of the axes and then turns 90 degrees to reach its destination. Experimental results that show the precision of the positioning system are presented. [ABSTRACT FROM AUTHOR]

A new hybrid nine level multilevel inverter (H9MLI) topology is proposed and developed with the combination of switched capacitor (SC) and H-bridge structure. The main features of the proposed inverter are voltage boosting capability, reduced switch count, reduced switching control and extended vertical and horizontal topologies. In this paper, the operation modes, modulation strategy, power loss analysis and the simulation results for H9MLI and its extended topology (13 level and 17 level) are presented. The MATLAB/Simulink based simulation of the proposed inverter and its extended topologies for static and dynamic loads are analyzed and verified. The quantitative comparison indicating the merits of proposed topology over various prior-art multilevel inverter topologies were evaluated and tabulated in an inclusive way. The level shifted PWM technique is used for generating control pulses for the proposed inverter. [ABSTRACT FROM AUTHOR]

The paper presents a way of accomplishing a non-contact excitation by electromagnetic waves generated from a system that includes WiFi microcontroller, H-Bridge and coil. The ESP 32 microcontroller software achieves PWM signal, which follows' a sinusoidal shape of variable frequency. The PWM signal drives the H-bridge resulting in a more powerful electric signal that also drives the coil, accomplishing in this way the pseudo-sine electromagnetic wave. The source code from microcontroller provides variable frequency and working period as well. The main features of the system are 0.5 to 3000 Hz, working periods between 0.1 and 10 seconds, the possibility to achieve more than one working period with standby periods in between. [ABSTRACT FROM AUTHOR]

Hybrid circuit breaker (HCB) has shown good performance for interrupting dc fault current. However, a massive number of IGBTs in series is needed. These will lead to high costs and significant difficulty in balancing IGBT dynamic voltage. This paper proposes a bidirectional hybrid circuit breaker based on a cascaded half-bridge submodule structure to reduce the overall costs and implementation difficulty of HCB. The number of IGBTs is reduced by 50%, and the operating speed is fast enough. A model of a four-terminal modular multilevel converter (MMC) system with a proposed hybrid circuit breaker in different stages is developed to describe the fault blocking process more clearly. The performance of the proposed HCB is validated and compared with other HCB structure through both theoretical derivation and time-domain simulation. [ABSTRACT FROM AUTHOR]

This paper presents a new switched-ladder structure for multilevel converter which consists of several bidirectional and unidirectional switches along with DC voltage sources. The values of DC sources in the proposed topology are determined based on a new mathematical algorithm. The proposed multilevel converter is an extended structure, which can produce any levels at output voltage waveform. To prove the merits of the proposed structure, the proposed converter is compared with other similar structures. According to comparison results, it is shown that the presented structure requires the least numbers of DC sources, IGBTs, drivers and on-state switches. Also, the value of voltage rating of the switches is analyzed. The experimental results are provided for the proposed 17-level converter to prove the performance of suggested structure. [ABSTRACT FROM AUTHOR]

Simulation of SIMO based DC-DC Converter for multi level Solar PV Inverter is presented in this paper. In order to reduce the number of distinct DC supplies for an H-bridge inverter SIMO DCDC converter is applied which in turn allows the usage of single PV system for a multi level H-bridge inverter. Simulation model of three level and five level inverters is built and results are presented to validate the proposed ideas.

The paper presents a way of accomplishing a non-contact excita-tion by electromagnetic waves generated from a system that in-cludes WiFi microcontroller, H-Bridge and coil. The ESP 32 mi-crocontroller software achieves PWM signal, which follows’ a si-nusoidal shape of variable frequency. The PWM signal drives the H-bridge resulting in a more powerful electric signal that also drives the coil, accomplishing in this way the pseudo-sine electro-magnetic wave. The source code from microcontroller provides variable frequency and working period as well. The main features of the system are 0.5 to 3000 Hz, working periods between 0.1 and 10 seconds, the possibility to achieve more than one working peri-od with standby periods in between.

This paper presents a method that enables a small car to reach its destination in an indoor environment using ultrawideband technology. For this purpose, we used four anchors and one tag. The tag can move because it is fixed on the car. The anchors and the tag are DWM1001 modules. The configuration of the five DW1001 modules is performed through a smartphone application provided by the manufacturer. The car has been built by us. The controller of the car is a Raspberry Pi microcomputer which controls the driver of the car DC motors by generating PWM signals. In addition, Raspberry Pi communicates with the tag by the UART interface. Thus, our goal was to control the car to reach a certain destination (xd, yd) requested by the user via Wi-Fi. Because the car hosts the tag, it continuously updates its position according to the information received from the four anchors. We implemented two scenarios, considering the initial (x, y) position of the car. In the first scenario, which is simpler, the car moved to its destination either along the x-axis or along the y-axis. In the second scenario, the car moves along one of the axes and then turns 90 degrees to reach its destination. Experimental results that show the precision of the positioning system are presented.

This study analyzes a single-phase hybrid multilevel dc-link (MLDCL) inverter, in which a dc-link with two capacitors is integrated into a single dc source. When controlled under the conventional modulation scheme, the MLDCL inverter synthesizes a five-level output voltage. As the capacitor-voltage balancing depends on the fundamental period, the output voltage may contain unsolicited low-order harmonics. Moreover, in the conventional scheme, this inverter requires large dc-link capacitors. To avoid these problems, the present paper develops a simple phase-shifted pulse-width modulation scheme based on redundant switching states, which controls the MLDCL inverter and balances the capacitor voltage within each carrier period. The proposed modulation scheme also minimizes the dc-link capacitance by a factor of the frequency modulation ratio while reducing the total harmonic distortion of the output voltage and current. Unlike the conventional method, the proposed scheme considerably reduces the capacitor-voltage ripples and can be regulated by increasing the carrier frequency, thereby reducing the voltage stress on the switches and improving the reliability of the inverter. The feasibility of the proposed scheme over the conventional scheme is confirmed in a comparative study. Finally, the steady-state and dynamic performances of the proposed strategy are demonstrated in simulations and validated in experiments.

In this paper, the compensation of voltage sags and swells using a dynamic voltage restorer (DVR) based on a bi-directional AC/AC converter is presented for stabilizing single-phase AC line voltage. The H-bridge AC/AC converter with bi-directional switches and without bulk capacitor is adopted as the power topology of the proposed system. The proposed novel topology of DVR is adopted to compensate both voltage sag and swell conditions. Additionally, the power factor is closed to unity because a bulk capacitor is not required. The inner and outer loop control is proposed to improve the response with gain scaling; gain control is adopted to reduce the overshoot. Finally, a 2 kVA prototype has been implemented to verify the performance and accuracy of the control method for the DVR system. The peak efficiency of the system is up to 94%, and it can compensate 50% voltage swells and 25% voltage sags. [ABSTRACT FROM AUTHOR]