Full Bridge Research Articles

Energy harvesting through piezoelectric technology

Small-scale energy harvesting using non-conventional methods are becoming very popular because they are eco-friendly. When the vehicles move on the road, the energy from vehicle movement can be harnessed using piezoelectric transducers. This paper proposes a scheme for harvesting the energy using piezoelectric technology to power a DC lamp of 12 V and 12 W. Synthetic-type Lead Zirconate Titanate (PZT) piezo transducers are used in the current work. These transducers are highly sensitive to applied pressure but the voltage generated will be less than 1.5 V from each cell. Therefore, 16 cells are connected in series to obtain a voltage of 24 V. The voltage generated from piezo transducers will be alternating in nature. Therefore, this voltage is rectified using a 1ϕ full bridge rectifier. The rectifier output is fed to a DC-DC buck-boost converter to get the required voltage and currents for a DC load of 12 W. Modeling of the piezo transducer, simulation and experimental results of the proposed method are presented in this paper. The proposed configuration can be deployed to harvest energy on the roads due to vehicle movements which can be used for lighting the lamps on the roads.

A space vector pulse width modulation method for switched reluctance motor driven by full bridge power converter

AbstractThis study proposes a space vector pulse width modulation (SVPWM) driving method for the switched reluctance motor (SRM), which enables the use of a standard full‐bridge power converter to drive a three‐phase SRM with a ring structure, in place of the traditional asymmetric H‐bridge (AHB). Based on this driving topology, the SVPWM approach is employed to drive the SRM, and its performance is compared with that of the conventional SRM driving method utilising the AHB. The findings indicate that the SVPWM method can effectively reduce torque ripple in the SRM. Moreover, the experimental validation performed to verify the proposed driving topology and method yields results that closely align with the simulated outcomes.

A robust voltage control of dual active full bridge converter based on RBF neural network sliding mode control with reduced order modeling approach

This paper presents a control method of dual active full bridge (DAB) DC/DC converter based on neural network Sliding mode control under the reduced order modeling method, which is used to enhance the output voltage regulation and improve the system robustness. Sliding mode control (SMC) is famous for its robustness and improving the dynamic performance of nonlinear systems. However, it includes drawbacks such as complex modeling, chattering, and decreased tracking performance. Therefore, through the method of reduced order modeling, the Radial Basis Function neural network algorithm is selected to modify and design the traditional sliding mode variable structure controller, completing the design of neural network approximation terms and adaptive laws. The proposed reduced order modeling and RBF(Radial Basis Function Neural Network)-SMC scheme simplifies the dual active full bridge modeling process, completes the parameter approximation of the sliding mode controller, and eliminates the chattering problem. Firstly, through simulation and comparative analysis of commonly used modeling methods for dual active full bridge, a reduced order modeling method was adopted to simplify the design process. Then, by ingeniously designing the sliding mode surface and Radial Basis Function control law, and using neural network to modify the Sliding mode control technology, the chattering problem, load disturbance and voltage fluctuation influence of the sliding mode controller are improved. The stability of the control method is proved by Lyapunov stability theory. Finally, the proposed RBF-SMC method is compared with PI linear control and classical Sliding mode control methods through simulation and experiments to verify the effectiveness of the proposed control method.

Isolated Interleaved Boost Converter Based Single-Phase Grid-Interfaced Photovoltaic System

An isolated interleaved boost converter (IIBC) based single-phase grid-interfaced photovoltaic system (SPGIPS) and its control are proposed in this article. The proposed double-stage SPGIPS consists of an IIBC and a single-phase full bridge voltage source converter (SPFBVSC). An IIBC is designed using a high-frequency transformer (HFT), two primary inductors, and two static switches with its emitter shared with photovoltaic (PV) panel ground. Shared emitter terminal reduces the gate control circuit complexity and HFT facilitates a galvanic isolation between PV panels and the utility grid, and thus it mitigates the appearance of leakage current. An IIBC reduces the ripple in PV panel current and voltages and therefore guarantees improved maximum power point operation (MPPO) of the PV system. To ensure the MPPO at PV panel terminals, a sliding mode control is used. The output DC terminals of IIBC are interfaced with self-commutated switches based SPFBVSC. To synchronize SPFBVSC with the utility grid, a new modified fourth-order generalized integrator (mFOGI) is developed. The mFOGI provides stable synchronization signal even under presence of noise, under/over shoot, or DC offset in the AC supply voltage. The proposed SPGIPS control and its performance are validated on Simulink and prototype system.

A simplified ANN-based evaluation method for creep sensitive girder bridge identification at preliminary design stage

Excessive deflection which exceeded expectations has been identified as one of the main problems contributing to long-term performance degradation of long-span girder bridges. Although the 3D refined finite element model of the full bridge can improve the prediction accuracy of long-term creep deformation, there is still a lack of efficient creep-sensitive structural judgment methods in the preliminary design stage. This study was thus intended to develop a new evaluation method and model to identify the possibility of excessive deflection will occur by utilizing simple structural design parameters, which contributed to new understandings of the creep deformation of bridge structural level. A finite element model database established by 20 long-span prestressed concrete girder bridges with actual project backgrounds was used for providing training, testing, and validation sample datasets for the artificial neural networks (ANN). The Back Propagation (BP) model was chosen for creating mappings among variables and results and solving complex problems with a fairly accurate prediction even without sufficient information. The indicator of deflection-span ratio difference between creep models was proposed as the key analysis factor. A case study was conducted to validate the effectiveness of the ANN model. The mean absolute error (MAE) between the results of the ANN model and FE analysis was 6.25%, which indicated a high consistency. The analysis of bridge design parameters using the ANN model revealed that it had a high risk of excessive deformation, which was consistent with the conclusion of the actual situation. Multiparameter sensitivity analysis results from the model also suggest that the side-span ratio, the main span, and the deflection caused by the pavement are the most three significant impacts compared to different input variables in this model. Based on the results, it can be concluded that the performance of the ANN-based technique can predict possible excessive creep problems in advance.

SELF-SUSTAINED POWER FOR MOBILE DEVICES: A STEPPER MOTOR-DRIVEN SOLUTION

This study introduces a self-sustained power solution for mobile devices using a stepper motor-driven mechanism. The objective is to ensure reliable power supply during critical situations when traditional sources are unavailable. A prototype device was designed and experimentally evaluated.The device utilizes a stepper motor as a generator, converting mechanical energy into electrical energy through a hand crank. A full bridge rectifier transforms the generated alternating current into direct current compatible with mobile devices. A battery serves as the primary power storage, enabling energy accumulation.Experimental testing verified the device's performance. Mobile devices, including cellphones, laptops, and routers, were connected to assess charging capabilities. The results demonstrated successful charging, providing dependable power during outages and inaccessible charging methods.The findings establish the stepper motor-driven self-sustained power device as a practical emergency power solution. It empowers individuals to maintain communication channels and power mobile devices during critical situations, enhancing resilience. Its versatility and portability ensure effectiveness in diverse locations where conventional power sources are unreliable.In conclusion, this study presents a novel self-sustained power solution employing a stepper motor-driven mechanism. Experimental results confirm its capability to charge mobile devices, supporting communication and resilience during emergencies. The device has significant potential to benefit individuals and communities, providing reliable power and improving emergency response and communication capabilities.

Numerical dynamic characterisation of concrete bridge stays

AbstractFollowing the recent collapse of a cable‐stayed bridge in Genoa, Italy, an interest has arisen to understand if it would have been possible for unknown localised material deterioration and/or decrease in prestress levels to introduce noticeable changes in the dynamic behaviour of RC stays. As such, in this study we start by reviewing past research work, experimental and analytical, on the effects that prestress level may or may not have on the dynamic response of RC beam elements. We then review also available analytical formulations used to determine the natural frequency of vibration of prestressed beams, and, subsequently, complete the preliminary investigation on the effects of prestress levels, and local damage, through the analysis of finite element models of prestressed beams and stays. The comparison of analytical and numerical estimations with results obtained from an in‐situ dynamic characterisation campaign on a RC bridge stay is also undertaken. In the second part of the study, we explicitly consider the Morandi bridge case‐study, for which finite element models of the stays alone, as well as of the full bridge, are developed and analysed. The obtained results are then also compared with the observations made in pre‐collapse in situ dynamic characterisation endeavours. All results obtained and discussed lead to the conclusion that, most regrettably, dynamic characterisation endeavours do not have the capability of providing insight on possible localised material deterioration or partial reduction of the average state of compression in this type of structural elements.

Analysis of ultimate seismic performance of thin-walled concrete-filled steel tube bridge piers under dynamic load

This study entailed the use of a cyclic loading test on a thin-walled concrete-filled steel tube (CFST) bridge pier to investigate its ultimate seismic performance. Additionally, a three-dimensional solid-shell finite element (FE) model of thin-walled CFST piers was established using ABAQUS. Cracks were introduced into in-filled concrete, and ductile damage was imposed on the steel tubes, in order to accurately reproduce the seismic performance degradation and post-earthquake residual displacement variation in thin-walled CFST bridge piers. The FE model was validated using pseudo-static and pseudo-dynamic loading tests performed on thin-walled CFST bridge piers. The analysis indicates that the FE model with concrete cracks can reflect the pinching effect of the hysteresis curve; the ductile damage can reflect the degradation of the bearing capacity during large plastic deformation under cyclic loading and the residual displacement under unidirectional and bidirectional dynamic loading. The seismic response of the full in-filled thin-walled CFST bridge pier was the least under the same intensity seismic wave, the in-filled concrete could improve ultimate seismic capacity. Finally, this study established a formula for the relationship between the residual and maximum displacements at the top of thin-walled CFST bridge piers under bidirectional seismic waves.

Inherently boosted switched inductor hybrid converter with AC and DC outputs for DC nanogrid applications

This paper presents a novel hybrid converter which is capable of carrying AC and DC loads simultaneously at different ports. The converter is designed by using a full bridge inverter at the nodes between the active switched inductor based high gain DC-DC converter. After inserting impedance into the current path, the inherent protection against the shoot through that often happens with a voltage source converter (VSI) is established. In addition, the modulation is such that the converter does not have to rely on shoot through to work, like most hybrid converters do. Instead, an extra charging mode has been added. This not only increases the voltage gain but also provides a flexible control with two duty ratios. The steady state operation of the converter is analyzed in five modes and their voltage relations are found out. A suitable pulse width modulation is realized to generate the different modes of operations. A prototype of the proposed converter is developed in the laboratory which is tested for suitable duty ratios operating for a maximum power of 600 W when the input voltage is maintained at 32 V. The converter finds its suitability in the nanogrid/microgrid where different loads are to be supplied from a single source.

Analysis and Design of a Partial Power Processing Architecture for High Step-Up Applications

Combining the advantageous features of the traditional two-stage and input-parallel-output-series (IPOS) structure, this paper proposes a partial power connection method for step-up applications with the advantages of wide input voltage range, galvanic isolation and partial power voltage regulation. In the proposed structure, the non-isolated DC-DC converter handles a small portion of the total power to regulate the system output voltage by simple PWM control. The latter stage should be a full bridge structure and the partial power processing is realized with different input voltages of the two bridge arms, which is beneficial to reduce the total number and cost of components, and two connection architectures are achieved in this way. The operation characteristics of the two architectures are analyzed in detail in this paper, and an optimal structure is obtained from the perspective of fewer components and better partial power processing capacity. Further, an isolated full bridge DC-DC converter with secondary resonance is selected to operate at the unregulated state as an application case to verify the feasibility and advantages of the proposed structure. An experimental prototype with 32-40V input voltage range and 400V/ 0.5A output is built with 1MHz switching frequency. The peak measured efficiency at 40V full load is 95.3%.

A Multi-Port DC Power Flow Controller Integrated With MMC Stations for Offshore Meshed Multi-Terminal HVDC Grids

Multi-terminal dc (MTDC) systems have the potential to facilitate the integration of offshore wind farms. A dc power flow controller (DPFC) is necessary for meshed multi-terminal high voltage dc (HVDC) grids to regulate the power flow in dc lines. However, DPFCs based on modular multilevel converters (MMCs) require two dc-ac conversion stages and an extra ac transformer, which increases the cost and loss for offshore platforms. This paper proposes a multi-port DPFC that is integrated internally into the offshore MMC station, eliminating the need for an extra transformer and reducing dc voltage ripple. Additionally, the full bridge submodules (FBSMs) in the DPFC can further reduce the number of FBSMs required in the MMC station for dc fault blocking. The proposed DPFC is composed only of cascaded FBSMs connected to the arms of the offshore MMC station, which can exchange power directly with the MMC valve to achieve power balance. By using the MMC station, the proposed DPFC requires a small kVA rating, approximately 1%-5% of the total system power rating. The performance of the proposed DPFC is validated through simulation of a hybrid system of the IEEE 39 bus and the Cigre HVDC benchmark, and also through down-scale experimental testing.

Novel Distributed Control Platform and Algorithm for a Modular Multilevel Matrix Converter

The Modular Multilevel Matrix Converter (M3C) is an attractive topology for low-speed drives and DFIG applications. Both modularity and scalability make the topology attractive for high-power medium-voltage systems. One of the main challenges for the design and implementation of an M3C is the control platform, which has to handle a high number of submodules and measured values. This paper introduces a new control platform including a high-speed communication network between the distributed control units. The control platform and algorithms are implemented on a 15 kvar M3C test bench with 108 full bridge submodules.

Temperature Equalization of a Multilevel Converter’s Low-Voltage Cell Power Modules

The reactive power compensator based on a multilevel converter contains series-connected low-voltage power cells. Each low-voltage cell is a full bridge consisting of two power modules. The air flow from the cooling system is heated under the first power module, and the second module following the first one is cooled less efficiently. The temperature difference under the modules of one cell reaches 10 °C. The article proposes a control algorithm with which the switching losses are redistributed between the modules so that to reduce the temperature difference. By changing the matching of the pulse-width modulation of the switches to the positive and negative bus of the cell DC link, the required ratio of switching losses between the two power modules is achieved, which makes it possible to reduce the temperature of the hottest one of them. A low-voltage power cell thermal model developed in the PSIM environment and a radiator model calculated using the finite element method are considered. The parameters of the simplified thermal model are estimated; the losses in power cells at zero output voltage are determined, and the ratio of their operation at zero output voltage is changed. The study results have shown that the proposed algorithm equalizes the temperatures and reduces the temperature under the module by 10 °C during operation at rated load.

Robust Cascade MRAC for a Hybrid Grid-Connected Renewable Energy System

Hybrid grid-connected renewable energy systems have gained significant importance in sustainably responding to an increased electrical energy demand. These are time-varying nonlinear dynamical plants, where the value of their parameters depends on changing weather conditions and the alternating grid voltage with randomly fluctuating amplitude. This paper proposes a robust cascade MRAC for nonlinear plants representing a class of these systems, which includes n renewable energy converts and a DC/AC single-phase full bridge inverter. The proposal reduces commissioning time by avoiding linearization and knowledge of the plant parameters. Moreover, it includes specific formulas for tuning the controller parameters that decrease their adjustments based on trial and error. Finally, it uses a direct adaptive method with adaptive laws having σθ modification and an inner loop at least five times faster than the outer loop. The proposition validation includes the theoretical stability proof based on the Lyapunov stability method and Barbalat’s Lemma. Furthermore, it presents comparative simulation results with quoted cascade PI controllers for a monophasic system, including two renewable energy sources and injection. Both techniques effectively track setpoint changes of the energy sources’ currents and direct current bus voltage, showing the proposal similar or reduced ripple. At the same time, both ensure robustness against decreased photovoltage panels irradiance, increased fuel cells voltage, and grid voltage amplitude random fluctuations. However, the proposal does these things while avoiding prior linearization and unknowing the plant parameters.

Diode-Assisted Gate-Commutated Thyristor for Hybrid MVDC Circuit Breaker Applications

This paper presents a Hybrid Circuit Breaker for Medium Voltage Direct Current grids, consisting of an ultra-fast mechanical breaker and a parallel Diode-Assisted Gate-Commutated Thyristor. This device is a GCT based devices, especially developed for this application. It has a higher current interruption capability than commercial IGCTs and a more robust, power-efficient and faster gate drive unit. We designed a stray inductance optimized package with an integrated gate drive unit for the Diode-Assisted Gate-Commutated Thyristor and included diodes with a very high forward voltage drop, which were radiated especially for use in a Diode-Assisted Gate-Commutated Thyristor, to increase its current turn-off capability. The build prototype can interrupt fault currents of 10 kA. An analysis of the stray elements in the package showed a possible increase of the current interruption capability to xy. We analysed the boundary conditions for potential use in an Hybrid Circuit Breaker by investigating the turn-on and turn-off characteristics of the device embedded in a diode full bridge and including a snubber capacitor.

Highly Linear RMS Microwave Power Sensor Joule-Heating-Based Using CMOS Technology

This article presents the design and implementation of a high-power handing capacity, wideband, and excellent microwave-dc linearity root-mean-square (rms) microwave power sensor (PS) in 180-nm standard RF CMOS technology. The detection technique utilizes two well-matched microwave power absorbers and a balanced Wheatstone full bridge (WFB) with thermistors to produce a dc output proportional to incident microwave power. The lateral spacing between the hot and cold zones of WFB with 80, 100, 120, 140,and 160 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\mu}$</tex-math> </inline-formula> m has been investigated experimentally, which provides insight into the proper adjustment of the layout parameters. The experimental result of the vector network analyzer (VNA) shows that the input reflection loss is less than <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$-$</tex-math> </inline-formula> 22.3 dB in the frequency range of 0–20 GHz. This indicates that the designed microwave PSs have good impedance matching characteristics. Moreover, it is demonstrated that the inherent linear relationship between the output dc voltage and the incident microwave power is less than 1.6% over a dynamic range of 1–500 mW. The proposed microwave PS can be further integrated in <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\textit{X}$</tex-math> </inline-formula> -band RF transceivers, offering high microwave-dc linearity, acceptable sensitivity, small size, and low cost for improving power transfer efficiency and optimizing the performance of the transmitting and receiving chain.

Bidirectional inductive underwater wireless power transfer converter with variable structure

The undersea sensor networks have an important function in marine resource exploration. To prolong the lifetime of the sensor networks, a bidirectional inductive underwater wireless power transfer (BI-UWPT) system with variable structure is proposed. With the proposed system, the autonomous underwater vehicle (AUV) could receive energy from the undersea docking station and transmit energy to the undersea sensor networks. The two full bridge topologies and the SS compensation networks are adopted in the system to achieve the bidirectional power transfer. To achieve bidirectional energy transmission of different power levels, two different operating frequencies and variable compensation capacitors are employed by the AUV. The system mathematical model is also presented. To verify the theoretical analysis, a 432 W simulation model when the AUV receiving electric energy and a 96 W simulation model when the AUV transmitting electric energy are constructed, respectively. The theoretical analysis is verified by the simulation results. Simulation results show that the variable compensation networks can obtain high transfer efficiency of the BI-UWPT system.

Single Phase MOSFET Inverter Using PWM Technique

Abstract: Electricity has two types which are DC (Direct Current) electricity and AC (Alternating Current) electricity. Electricity which generally used for household components is utilized AC electricity. AC power can be generated from DC electricity by using an inverter tool. The inverter has various methods of converting DC power to AC power. In this research, inverter built using full bridge configuration. Using the full bridge configuration, it is obtained more efficient results by using other configurations. The inverter designed using voltage source 12 volt battery with a capacity of 7.5 Ah. The maximum power capacity which generated by the inverter is 100 watts. To control this inverter, Arduino uno R3 microcontroller is used.

Reliability Analysis of Multi-Level PFC Converter-Based Charger for Light EV Charging Application

Electric vehicle (EV) charging architectures with two stages consist of rectification and a DC–DC conversion stage. Multi-level rectifiers are emerging as better alternatives in the rectification stage of EV charging applications. As they possess minimum voltage stress on switches, better harmonic profile at the grid side, lower dv/dt stress, and higher voltage capability. In this article, a five-level rectifier in conjunction with a phase shift full bridge converter is implemented for EV charging applications. The rectifier has the inherent capacitor voltage balancing capability and maintains unity power factor at the source side under varieties of operating conditions. The reliability of power electronic converters can be estimated by accessing the reliability of each component in converters. To establish the suitability of the implemented system for real-time EV charging applications, comprehensive performance analysis has been carried out including reliability assessment, the impact of parametric variations on reliability, calculation of losses and efficiency. The battery charger is mathematically modeled and validated experimentally in laboratory. The comparative analysis of the rectifier with state-of-the-art literature has been also carried out.

A Six-Switch Mode Decoupled Wireless Power Transfer System with Dynamic Parameter Self-Adaption

For the fully resonant wireless power transfer (WPT) system, the high coupling of the converter and the resonant network introduced many problems, such as frequency splitting, the power curve peak limit, and the strict switch strategy. To solve these problems, this paper proposed a new six-switch topology based on the full–-bridge converter. With the unique structures containing two capacitor-isolated switches and a source-isolated diode, the system decouples the converter and the resonant network, and its modes have been decoupled, called the independent power injection and free resonance WPT (IPIFR–WPT) system. The capacitor-isolated switches and the source-isolated diode make the converter operate only when the voltage on the primary capacitor is equal to the source voltage, and the source will be isolated by the diode when the capacitor voltage is great than the source, which provides a wide time margin for the switches of the converter to turn on in advance. In this margin, the operation point is self-determined the same whenever the switches turn on so that the system’s performance is consistent. Based on this characteristic, the system can self-adapt a dynamic change in system parameters, with at least 15% tolerance for the coupling coefficient and 14% for the load resistance.