Design of a Modified-Bridge Circuit with a Master-Slave Input Supply Mechanism for Ozone-Driven System Applications

This study proposes a design of a modified-bridge circuit with a master–slave input supply mechanism for ozone-driven system applications. Because the single-source supply design is becoming the mainstream choice in the existing ozone-driven systems, the input supply reliability of the ozone-driven system is crucial. Therefore, this proposed design involves a modified-bridge circuit combined with inductors and transistors, which can be augmented with the energy storage device as a backup source to improve the reliability of the input supply for the ozone-driven system. In addition, considering that the original source directly connected to DC BUS can re-charge the energy storage device, the energy recycling operation mode is designed in this proposed system to extend the duration of the energy storage device, which improves the supply reliability of the ozone-driven system further. To validate this proposed system, both model formulation and hardware realization are assessed through different test scenarios. Experimental outcomes of these tests confirm the practicality of the proposed design.

A single-stage full bridgeless boost half-bridge AC/DC converter with bidirectional switch

This paper proposes an isolated full bridgeless single stage alternating current-direct current (AC-DC) converter. The proposed converter integrates the operation of a pure bridgeless power factor correction with input boost inductor cascaded with center-tap transformer and half bridge circuit. In addition, the bidirectional switch can be driven with single control signal which further simplifies the controller circuit. It is also proved that this converter reduces the total number of components compared to some conventional circuit and semi-bridgeless circuit topologies. The circuit operation of the proposed circuit is then confirmed with the small signal model, large signal model, circuit simulation and then verified experimentally. It is designed and tested at 115 Vac, 50 Hz of input supply, and 20 Vdc output voltage with maximum output power of 100 W. In addition, the crossover distortion at the input current is minimize at high input line frequency.

Comparative investigations on different types of inductors in single-phase inverter

This article organized in two sections where it compares the performance of single-phase inverters using various types of inductors with differences modulation technique of pulse width modulation (PWM). Not all inductors perform the same function, even the inductance value is the same. The study will investigate the capability of each inductor on its performance to convert the unfiltered AC voltage into filtered sinusoidal AC voltage. The drum core and toroidal core inductors were used in this investigation. For both inductors, the performance will be analyzed based on Bipolar and Unipolar switching schemes in a single unit H-bridge circuit. The validation of results are through experimental assessment only and it will be evaluating the shape of sinusoidal AC voltage and the content of total harmonics distortion in the AC voltage for both inductors.

Analysis of the Downhole Measurement System’s Pressure and Temperature Measuring Channel Calibration Errors

Various measurements in wells are quite challenging due to the specific measurement conditions. There are some additional requirements for measurement systems, in particular, space restrictions. Therefore, measuring several parameters with a single sensor is rather important. The paper discusses a measurement system that allows measuring temperature and pressure with a single sensor – an SOS-based strain gauge pressure transducer with a bridge or half-bridge circuit. In this case, pressure and temperature measuring channels are calibrated individually, which creates another error component. The numerical simulation of calibration described herein shows that regardless of the sensor circuit, the voltage uncertainty band of both measuring channels is characterized by a reduced error of 0.03 % with a confidence probability P = 0.9.

A series-connected switched source and an H-bridge based multilevel inverter

An inverter circuit is promoted in this paper, using series-connected switched dc sources along with an H-bridge circuit with optimized circuit elements like switching devices and diode clamped (DC) sources. This configuration uses DC supplies that can be strung together in series to create a significant voltage level. This topology consists of two parts, namely: 1) level production part and 2) polarity production part. The combination of some of the dc sources and switching devices completes the level production part. The H-bridge in the presented structure produces the polarity generation part. The DC-link capacitors are not needed in this design. There is a full presentation of the operating modes and modeling process of the proposed converter. Finally, in the MATLAB/SIMULINK setting the proposed topology is simulated and output current and voltage results have been examined.

Implementation of a Resonant Converter with Topology Morphing to Achieve Bidirectional Power Flow

A DC converter with the benefits of reverse power capability, less switching loss and wide voltage operation is presented and implemented for wide input voltage applications such as fuel cell energy, photovoltaic (PV) system and DC wind power. Two full bridge resonant circuits are used in the presented converter to achieve bidirectional power flow capability and reduce switching losses on active devices. To overcome the wide input DC voltage variation problem for fuel cell energy and PV solar panel, the topology morphing between the half bridge circuit and full bridge circuit is adopted on the primary side to obtain low (or high) voltage gain under a high (or low) input voltage condition. Therefore, the stable DC voltage is controlled at the load side by using the variable switching frequency modulation. The studied hybrid CLLC converter is tested by a 1 kW prototype and the performance is verified and confirmed by experiments.

Hardware Implementation of Differential Oscillatory Neural Networks Using VO 2-Based Oscillators and Memristor-Bridge Circuits

Oscillatory Neural Networks (ONNs) are currently arousing interest in the research community for their potential to implement very fast, ultra-low-power computing tasks by exploiting specific emerging technologies. From the architectural point of view, ONNs are based on the synchronization of oscillatory neurons in cognitive processing, as occurs in the human brain. As emerging technologies, VO2 and memristive devices show promising potential for the efficient implementation of ONNs. Abundant literature is now becoming available pertaining to the study and building of ONNs based on VO2 devices and resistive coupling, such as memristors. One drawback of direct resistive coupling is that physical resistances cannot be negative, but from the architectural and computational perspective this would be a powerful advantage when interconnecting weights in ONNs. Here we solve the problem by proposing a hardware implementation technique based on differential oscillatory neurons for ONNs (DONNs) with VO2-based oscillators and memristor-bridge circuits. Each differential oscillatory neuron is made of a pair of VO2 oscillators operating in anti-phase. This way, the neurons provide a pair of differential output signals in opposite phase. The memristor-bridge circuit is used as an adjustable coupling function that is compatible with differential structures and capable of providing both positive and negative weights. By combining differential oscillatory neurons and memristor-bridge circuits, we propose the hardware implementation of a fully connected differential ONN (DONN) and use it as an associative memory. The standard Hebbian rule is used for training, and the weights are then mapped to the memristor-bridge circuit through a proposed mapping rule. The paper also introduces some functional and hardware specifications to evaluate the design. Evaluation is performed by circuit-level electrical simulations and shows that the retrieval accuracy of the proposed design is comparable to that of classic Hopfield Neural Networks.