Full-bridge Topology Research Articles

A Noninvasive Sliding Mode Observer Based Approach for Detecting Open-Circuit Faults in HERIC Inverters

This article presents a new technique for detecting and localizing the open-circuit (OC) faults in the semiconductor switches of the Highly Efficient and Reliable Inverter Concept (HERIC) converter. It is a transformerless Photovoltaic (PV) inverter based on the full-bridge topology, with two extra switches on the AC side called ac bypass switches. The proposed method uses a sliding mode observer (SMO) to detect faults in the AC bypass switch and main switches of the full bridge inverter. To diagnose OC faults in the AC bypass leg, two parallel SMOs are created based on the converter’s state space model. Similarly, two SMOs are designed for the main switches. A residual is generated by combining the observed and measured grid currents to accurately locate the OC fault within the inverter system. To localize the faulty main switch, once the fault is detected the inverter is reconfigured and based on the grid current the faulty switch is identified. A major benefit of this method is that it does not rely on additional sensors for fault diagnosis, making the system more robust. The effectiveness and reliability of this approach are demonstrated through simulation studies. In addition, a laboratory prototype is developed to validate the practical applicability of the method.

Design and Implementation of a Non-Destructive AC Heating System for Lithium-Ion Battery Modules

The electrification of transportation is experiencing rapid development. Electric bicycles (e-bikes) are commonly employed as convenient modes of transportation. Thanks to the advantages of long life and high energy density, lithium-ion batteries (LIBs) are widely used in e-bikes. In certain business models, e-bikes can utilize rental LIBs, which are centrally managed at charging stations. The low-temperature charging and discharging performance of the LIB system poses a significant challenge during usage. Among various heating methods, alternating current (AC) heating has garnered attention due to its high efficiency and has been applied to quickly warm up the LIB system. To address this issue, an AC heating model was established to determine the appropriate frequency and magnitude of the current, and a prototype AC heating system for the LIB modules used in e-bikes was designed. A full-bridge topology system model was established, and an experimental platform was constructed to test the effectiveness of the proposed AC heating topology and thermoelectric model under different AC heating frequencies and currents. The results show that the proposed AC heating system can heat an 18650 battery module within 20 min. Under an ambient temperature of −20 °C, using a 10 A, a 100 Hz excitation current achieves a heating rate of 1.3 °C per minute, with minimum power losses. The prototype also has a fast response time of only 70 ms. Finally, the strategies of LIB heating and insulation are proposed for the scenario of a battery swapping station. This research holds great significance in resolving the problem of low-temperature heating for e-bikes in cold regions.

Paralleled Variable Inductor Phase-Shifted Full-Bridge Converter With Full-Load Range ZVS and Low Duty Cycle Loss

This paper presents a new phase-shifted full-bridge topology using a new variable inductor. In this topology, a variable inductor is connected in parallel with a near-ideal transformer. The ZVS of the switches is achieved over the full load range using the parallel current provided by the variable inductor. And the adjustable parallel current reduces conduction losses. Under the orthogonal DC magnetic potential, the variable inductor has similar characteristics to the saturated inductor, which is beneficial to reduce the conduction loss caused by the parallel current. Since the topology has no series inductor and the leakage inductor is extremely small, the proposed converter has the advantages of extremely small duty cycle loss, larger transformer turns ratio, smaller primary current stress, smaller secondary voltage stress, and smaller output current ripple, which are beneficial to improve the efficiency and frequency of the converter. An experimental platform was established. Theoretical analysis and experimental verification were carried out.

Research on dual-mode switching of the new dual full-bridge topology of the beam supply

Research on dual-mode switching of the new dual full-bridge topology of the beam supply

State-Space Averaged Model of Three-Phase Four-Wire Shunt Active Power Filter Based on Current-Controlled VSI

This work presents a universal state-space average model of three-phase four-wire shunt active power filter based on current-controlled voltage-source inverters. In this type of inverters two topologies are commonly used, namely the Four-Leg Full-Bridge (FLFB) topology, and the Three-Leg Split-Capacitor (TLSC) topology. Combining these topologies, a third topology can be obtained, namely the Four-Leg Split-Capacitor (FLSC) topology. This last topology exhibits very interesting characteristics for active filter applications. By means study of FLSC topology a state-space average model can be obtained, which will allow long-time simulations with a low cost of computation time. The behaviour of FLFB and TLSC converters can be obtained as particular cases of this universal model. Likewise, a generic technique for injected current control is proposed, offering as main advantage a decoupled control of the different legs, so full-bridge converters can be implemented without using space-vector based current control techniques.

Bang-Bang Funnel Control of Three-Phase Full-Bridge Inverter Under Dual-Buck Scheme

This paper proposes a bang-bang funnel control strategy for the three-phase full-bridge inverter under dual-buck scheme. By adopting the so-called dual-buck scheme, only two switches on the different phase legs are controlled at high frequency, precluding the dead-time utilization. Furthermore, the full-bridge topology can be physically decoupled into two parallel-connected buck units, which allows the inverter to be formulated and analysed by the dynamic model of buck chopper. The bang-bang funnel controller (BBFC) works with just two control values, and it is able to restrain the tracking error between the system's output and the reference within the pre-specified funnel boundaries. The nature of BBFC makes it simpler, faster and more robust, suitable for the inverter operating in dual-buck scheme. The proposed strategy not only guarantees accurate static output performance, but also promotes the inverter's dynamic response against rapid variations of the load, the reference and the input voltage, as well as its robustness to the unexpected parameter changes of the elements. Finally, the effectiveness of the proposed strategy is validated by the simulation and experimental results.

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.

Soft-Switching Full-Bridge DC-DC Converter with Energy Recovery Capacitor Snubber

This paper describes a high-frequency soft-switching dc-dc converter with a simple energy recovery capacitor snubber on the secondary side. The presented dc-dc full-bridge converter with the energy recovery snubber removes the main drawbacks of the classic Phase Shifted PWM (PS-PWM) dc-dc converter, e.g., the circulating current flowing during the free-wheeling interval and dependency of the soft switching on the load current. The converter utilizes a full-bridge topology with pulse-width modulation and a centre-tapped full-wave controlled rectifier with one active switch. The zero-voltage switching on the primary side is ensured by utilising only the magnetizing current of the high-frequency transformer, and thus is load-independent. The proposed energy recovery snubber is described in detailed time waveforms of the converter and verified by simulation. The control algorithm also removes the circulating current, which is typical for PS-PWM converters. The soft-switching of the secondary side transistor is achieved by a simple capacitor snubber with an energy-recovery circuit connected to the output of the dc-dc converter. The principle of operation is verified by measurements on a 2 kW, 50 kHz laboratory model of the proposed dc-dc converter.

Design of Double Staggered Parallel Bearingless Motor Drive System

To make bearingless motors (BMs) more competitive, it is imperative to reduce the cost while ensuring high performance. In this article, the driving system of the BM is optimized from the perspectives of the inverter topology and the control strategy. A dual-hybrid vector control driving scheme of the BM based on the double staggered parallel topology is proposed for the control performance and cost. Meanwhile, the levitation/torque stagger phase shift is adopted to lower the root-mean-square value of the dc-link current. The proposed driving scheme is compared with the traditional vector scheme based on a full-bridge topology on a bearingless pump system. It turns out that the two driving schemes are similar in current, speed, and rotor radial displacement fluctuation. The proposed scheme shows the advantages of simpler system structure and lower cost, so it is deemed as an attractive driving scheme for the BM.

Research on ZVS Phase-Shifted Full-Bridge Broadband Inverter Based on Auxiliary Current Source

Phase-shifted full-bridge topologies are widely used in medium- and high-power DC/DC converters due to their small size and high switching frequency. However, there are few studies on the application of broadband inverters. In the traditional phase-shift full-bridge inverter with a fully resonant load, the problem of current commutation which leads to hard switching is often encountered, to overcome such an issue, an auxiliary current source network is introduced to realize the zero-voltage turn-on of the lagging bridge arm. The working modes of the converter are analyzed in detail, and the parameters of the auxiliary current source network are designed. The simulation verification is carried out by MATLAB/Simulink in a wide frequency range from 10 kHz to 500 kHz. Finally, an experimental circuit board is designed, and the experimental results show that the topology can achieve soft switching in a frequency range from 10 kHz to 200 kHz and has a certain applicability.

A multi-shift phase angle control strategy for bidirectional wireless power transmission system

Using the charging and discharging capability of battery-based loads and a two-way wireless energy transmission system, grid-load balancing can be achieved in both directions. The system can be applied to many locations by deploying power flow in real time. In the scenario of vehicle network interconnection, it realizes peak-shaving and valley-filling to optimize grid dispatching capability; in the scenario of modular satellite interconnection, it realizes load balancing and effectively improves energy utilization. Therefore, a suitable control strategy is needed to precisely change the output power flow and the output power magnitude. A method to coordinate multiple phase shifting angles in the system hierarchy to achieve power flow regulation is proposed for a bidirectional wireless power transmission system with a dual full-bridge topology. In this paper, we first model the bidirectional transmission system and analyze the relationship between each phase shift angle and active and reactive power. The traditional control strategy is optimized by reducing the number of control loop variables and using the system power factor angle instead of the difficult-to-control external phase shift angle, while ensuring the voltage gain for optimal system efficiency. Finally, only two control loops are used to control the direction and magnitude of the output power respectively, and the effectiveness and correctness of the control strategy are verified by using the corresponding simulation experiments to achieve smooth switching of the bidirectional electric power transmission power flow.

High-Voltage Power Supply for High Repetitive Rate Marx Generator with Quasi-Resonant Zero-Current Switching Transistor Control Algorithm

Due to having a number of advantages, Marx generators are still the most widely used devices for generating high-voltage pulses in many fields of science and technology. To ensure their proper operation, especially when the generation of many frequent, highly repetitive pulses is required, a highly efficient high-voltage power supply is needed. The paper describes a specially developed power supply (input voltage 48 V DC, output voltage up to 50 kV) based on the conventional Full Bridge topology with two high-frequency high-voltage transformers and a 6-stage voltage multiplier. In order to avoid many problems caused by low coupling between primary and secondary windings of the transformers and the large parasitic capacitances of the secondary windings, a special quasi-resonant zero-current switching transistor control algorithm with variable switching frequency (dependent on output load) was developed. In the described method, the energy is supplied to the transformer in short pulses, when a pair of diagonal transistors of the full-bridge converter were turned on. Then, the freewheeling state is maintained until all of the energy stored in the leakage inductance of the transformer has been transferred to the secondary side, which means that the current in the primary windings drops to zero. This approach reduces energy losses, electromagnetic disturbances and prevents current distortion in primary winding.

Single-Switch Wireless-Power-Transfer Circuit With P-CLC Compensation Network Used for Battery Charging

At present, most of the analyses or studies about wireless power transfer (WPT) with the load-independent characteristics of constant current output (CCO) and constant voltage output (CVO) are carried out based on full-bridge topologies. The study about single-switch circuits used in wireless charging is infrequent. However, compared with full-bridge topologies, the structure and the control strategy of single-switch WPT circuit are simple and avoid the shoot-through problem, which makes it more advantageous in reliability and cost. In this article, a single-switch WPT circuit with P-CLC compensation network is proposed to realize CCO and CVO at two different frequencies <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$f_{\mathrm {CC}}$ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$f_{\mathrm {CV}}$ </tex-math></inline-formula> , respectively. Compared with hybrid compensation, this switching method from CCO to CVO does not require extra mode switches and corresponding control circuits. Moreover, the transfer gain does not rely on the transformer parameters, and more parameters’ design freedom can be realized. The analysis of the P-CLC compensation network illustrates that the proposed charging circuit could have a long transmission distance in low frequency. The few passive devices are used in this circuit for higher efficiency and lower cost. Finally, the simulation and the experimental verification are carried out to verify the superiority of the proposed circuit.

An Isolated Multilevel DC–DC Converter Topology With Hybrid Resonant Switching for EV Fast Charging Application

This article proposes a multilevel dc–dc converter topology for fast charging of electric and plug-in hybrid electric vehicles (EVs and PHEVs). The proposed dc–dc converter topology converts the front end ac–dc converter output and provides regulated supply to the EV propulsion battery. The proposed topology consists of full-bridge converter at the primary, while the secondary side consists of voltage doubler rectifier units and combination of diodes and <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mosfet</small> for reconfiguration of the voltage doubler rectifiers to generate the multilevel voltage. The multilevel voltage at the output helps in reducing the output filter size and increases the power density of the converter. The topology utilizes the resonance between leakage inductor of high frequency transformer, parasitic output capacitors of full-bridge <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mosfet</small> s and voltage doubler capacitors to achieve soft switching (ZVS turn- <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</small> ) for all the full-bridge devices and soft turn- <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> for the rectifier diodes. The load limited ZVS turn <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</small> capability of conventional full-bridge topologies is mitigated through the use of resonance between magnetizing inductance of transformer and <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mosfet</small> output capacitors. The converter is designed for 650 V dc bus input and 200–400 V EV battery output at 100 kW rated charging power. The analysis of the proposed converter in continuous and discontinuous modes of operation, soft switching operation, and the component design guidelines are presented in this article. The proposed converter is validated through detailed PLECS simulation results for 100 kW charging power. Experimental results from laboratory prototype of 500 W power are also presented to validate the design methodology and converter performance.

Development of a Didactic Platform for Flexible Power Electronic Converters

Power electronic converters are the subject of several studies and applications. Knowledge about those converters is essential for several technical and undergraduate courses in the field of Electrical Engineering and related areas. The presence of converter modules in laboratories can be beneficial for experimental validations in academic research and educational purposes, for allowing students to have practical contact with different converter topologies and applications. However, the commercially available power converters are generally manufactured for specific applications, with poor versatility and high cost, when applied for academic purposes. For this reason, several laboratories propose the design of versatile converters, mainly for multilevel converter research. Nevertheless, most of these projects present module designs based on half bridge topology due to their low cost. Therefore, this project topology requires more modules to operate as topologies based on a full-bridge converter. Besides, modules based on full-bridge topology can also work in a half-bridge configuration. Thus, this work presents the design of full-bridge modules capable of operating as different types of converters, as well as the project of the dc-link voltage measurement, isolated power supply and bypass circuits. Moreover, this work addresses the heatsink choice, the thermal evaluation for the semiconductor devices and the realization of galvanic isolation between the signal and power circuits.

Soft-Switching Full-Bridge Topology with AC Distribution Solution in Power Converters’ Auxiliary Power Supplies

The auxiliary power supply in a power converter is a key topic in the optimization of the converter’s low-voltage electronic circuit performance. In this article, a low-voltage DC-AC soft-switching full-bridge topology, with an innovative, driven technique to achieve a zero-voltage transition, is presented and discussed. The full-bridge converter drives a high-frequency transformer (called the main transformer) that on the secondary side, distributes an AC voltage and current to the several electronic circuit’s supplies. Every power supply is composed of an HF transformer (called load transformer) that converts the AC secondary voltage of the main transformer to the voltage and current levels requested by the electronic circuit. In this paper, the operating conditions are first investigated by several simulation results. Furthermore, an actual DC-DC power converter is used as a workbench for an experimental investigation of the effectiveness of the proposed auxiliary DC-AC soft-switching topology, and the AC distribution approach, to realize the several points of load power supply requested. Finally, the advantages and drawbacks of this auxiliary power supply solution are critically discussed, providing guidelines for the power converter designer.

A Comprehensive Review on Modular Multilevel Converters, Submodule Topologies, and Modulation Techniques

The concept of the modular multilevel converter (MLC) has been raising interest in research in order to improve their performance and applicability. The potential of an MLC is enormous, with a great focus on medium- and high-voltage applications, such as solar photovoltaic and wind farms, electrified railway systems, or power distribution systems. This concept makes it possible to overcome the limitation of the semiconductors blocking voltages, presenting advantageous characteristics. However, the complexity of implementation and control presents added challenges. Thus, this paper aims to contribute with a critical and comparative analysis of the state-of-the-art aspects of this concept in order to maximize its potential. In this paper, different power electronics converter topologies that can be integrated into the MLC concept are presented, highlighting the advantages and disadvantages of each topology. Nevertheless, different modulation techniques used in an MLC are also presented and analyzed. Computational simulations of all the modulation techniques under analysis were developed, based on four cascaded full-bridge topologies. Considering the simulation results, a comparative analysis was possible to make regarding the symmetry of the synthesized waveforms, the harmonic content, and the power distribution in each submodule constituting the MLC.

Speed Control of Induction Motor Using Variable Frequency Driver (VFD) Method Based On Arduino Nano

This research aims to control the speed of an induction motor by exploiting changes in the fundamental frequency. The inverter as the main part of the variable frequency driver (VSD) uses the IRFZ44n Mosfet as a power switch with a full bridge topology to convert the DC source to AC power. Fundamental frequency manipulation takes place during the conversion process. The method used is to change the variable fundamental frequency of the SPWM signal generated by the Arduino nano to control the power switch. Experiments are carried out based on two stages, namely simulation, and experiment. The simulation is performed using the Pspice A/D Lite software to take time sample data (HIGH and LOW) at each frequency change of 13Hz, 25Hz, 38Hz, and 50Hz, then the sample data is input on the Arduino nano as an SPWM signal generator to control the power switch. The results of the variable frequency drive test are the frequencies generated to drive the induction motor at 12.50 Hz, 24.04 Hz, 35.71 Hz, and 48.54 Hz at motor speeds from 227.7 to 1359.6 rpm.

A Current Amplifier Circuit and Control Strategy Based on FPGA

With the extensive application of electric vehicles, energy storage systems and other power electronic equipment, the research on large capacity controllable current source will be an important direction in the future. This paper proposes controllable current source controlled by a full digitally hysteresis current based on field programmable gate array(FPGA), in which the single phase full bridge topology is adopted as the main circuit of current source. The two levels and three levels hysteresis current control strategies are analyzed and compared with the platform of PSCAD/EMTDC. The user defined component was adopted to realize the two difference control strategies with fortran language program. The simulation results verified that the two levels hysteresis current control strategy is much more fit for the controllable current source. Finally, a prototype is designed and fulfilled and it is controlled by the digitally controller with FPGA. The hysteresis current control is realized by FPGA controller with VHDL programming. The experimental results show that the researched hysteresis current control technology is effective for the current amplifier

An Optimized Single-Stage Isolated Swiss-Type AC/DC Converter Based on Single Full-Bridge With Midpoint-Clamper

The Swiss-type rectifier (SR) uses harmonic injection circuit and two dc–dc converters to help three-phase uncontrolled rectifier bridge to achieve better power factor correction (PFC). By applying the full-bridge topology to the dc structure, both the soft switching and the high-frequency galvanic isolation can be achieved. However, two full-bridge structures are required to realize the PFC principle of SR. That means the current flows through at least four switches and two transformers during the power conduction or freewheeling period. There are improvements in both conduction loss and core utilization. Thus, an optimized single-stage isolated Swiss-type ac/dc converter based on a single full-bridge with midpoint-clamper is proposed. Only one full-bridge structure is used to improve the conduction loss and core utilization. Two bidirectional voltage clampers are used to implement the PFC principle of the SR. The performance of the proposed converter has been verified by experiments. A total of 95.4% efficiency under half rated power and 5% input current THD under rated power have been achieved under a 10-kW 380 Vac input/400 Vdc output prototype with 90 kHz switching frequency.