scholarly journals A High-Efficiency Three-Level ANPC Inverter Based on Hybrid SiC and Si Devices

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1159 ◽  
Author(s):  
Zhijian Feng ◽  
Xing Zhang ◽  
Jianing Wang ◽  
Shaolin Yu
Keyword(s):  
Silicon Carbide ◽  
High Efficiency ◽  
The Other ◽  
Switching Frequency ◽  
Parallel Operation ◽  
Switching Loss ◽  
Hybrid Scheme ◽  
Excellent Performance ◽  
Switching Losses ◽  
The Cost

Silicon carbide (SiC) devices have excellent performance, such as higher switching frequency and lower switching loss compared with traditional silicon (Si) devices. The application of SiC devices in inverters can achieve higher efficiency and power density. In recent years, the production process of SiC devices has become more mature, but the cost is still several times that of traditional Si devices. In order to balance cost and efficiency, replacing only some of the Si devices with SiC devices in a topology is a better choice. This paper proposed a high-efficiency hybrid active neutral point clamped (ANPC) three-level inverter which has only two SiC devices and the other devices are Si devices. A specific modulation strategy was applied to concentrate switching losses on the SiC devices and reduce the on-state loss through parallel operation during freewheeling intervals. Theoretical efficiency curves and experimental verification of the proposed hybrid scheme with Si-only and SiC-only schemes were carried out.

Load-Adaptive Soft-Switching Energy Recovery Sustainer for Plasma Display

2012 ◽  
Vol 241-244 ◽  
pp. 632-635
Author(s):  
H. L. Do
Keyword(s):  
Theoretical Analysis ◽  
Energy Recovery ◽  
Soft Switching ◽  
Switching Frequency ◽  
Switching Loss ◽  
Switching Characteristic ◽  
Switching Losses ◽  
Plasma Display ◽  
And Performance ◽  
A Current

In this paper, an energy recovery for plasma display is proposed. The proposed energy recovery sustainer provides soft-switching of main sustain switches and reduces the switching loss. Due to soft-switching characteristic, the switching losses of main switches are significantly reduced. In addition, the conduction losses in both main and auxiliary switches are effectively reduced by varying a current build-up time according to image patterns. Theoretical analysis and performance of the proposed energy recovery sustain driver were verified on an experimental prototype operating at 200 kHz switching frequency.

scholarly journals Constant-Current, Constant-Voltage Operation of a Dual-Bridge Resonant Converter: Modulation, Design and Experimental Results

2021 ◽  
Vol 11 (24) ◽  
pp. 12143
Author(s):  
Jiaqi Wu ◽  
Xiaodong Li ◽  
Sheng-Zhi Zhou ◽  
Song Hu ◽  
Hao Chen
Keyword(s):  
High Efficiency ◽  
Experimental Tests ◽  
Rechargeable Batteries ◽  
Constant Current ◽  
Switching Frequency ◽  
Resonant Converter ◽  
Constant Voltage ◽  
Switching Loss ◽  
Wide Range ◽  
Modulation Methods

To meet the requirements of charging the mainstream rechargeable batteries, in this work, a dual-bridge resonant converter (DBRC) is operated as a battery charger. Thanks to the features of this topology, the required high efficiency can be achieved with a wide range of battery voltage and current by using different modulation variables. Firstly, a typical charging process including constant-voltage stage and constant-current stage is indicated. Then, two different modulation methods of the DBRC are proposed, both of which can realize constant-voltage charging and constant-current charging. Method I adopts phase-shift modulation with constant switching frequency while Method II adopts varying frequency modulation. Furthermore, as guidance for practical application, the design principles and detailed design procedures of the DBRC are customized for the two modulation methods respectively in order to reduce the switching loss and conduction loss. Consequently, the full soft-switching operation with low rms tank current is achieved under the two modulation methods, which contributes to the high efficiency of the whole charging process. At last extensive simulation and experimental tests on a lab prototype converter are performed, which prove the feasibility and effectiveness of the proposed modulation strategies.

Analysis and Mitigation of Valve Switching Losses in Switched Inertance Converters

2015 ◽  
Author(s):  
Travis K. Wiens
Keyword(s):  
Pressure Drop ◽  
Trade Flow ◽  
The Other ◽  
Energy Losses ◽  
Switching Loss ◽  
Highly Efficient ◽  
Switching Losses ◽  
Overall Performance ◽  
Valve Switching ◽  
Flow Valve

Switched inertance converters use digital valves to exploit the inertia of a flow in order to trade flow for pressure or vice versa. These components can be used to efficiently match load and supply pressures, avoiding the energy wasted by using resistive valves. While theoretical switched inertance converters can be highly efficient, practical implementations suffer from a number of energy losses. One of these losses is the valve switching loss: the energy wasted due to the flow experiencing a pressure drop across the partially open valve as the digital valve shifts from one position to the other. This paper quantifies the effect of this loss on the valve’s overall performance. Two novel strategies for mitigating this effect are introduced: a shaped inertance tube design and positioning of the tank-flow valve along the length of the inertance tube.

scholarly journals A Comparative Study on the Switching Performance of GaN and Si Power Devices for Bipolar Complementary Modulated Converter Legs

Energies ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 1146 ◽  
Author(s):  
Baochao Wang ◽  
Shili Dong ◽  
Shanlin Jiang ◽  
Chun He ◽  
Jianhui Hu ◽  
...  
Keyword(s):  
Comparative Study ◽  
Dead Time ◽  
High Electron Mobility Transistors ◽  
Buck Converter ◽  
Switching Frequency ◽  
High Electron ◽  
Switching Loss ◽  
Gan Hemt ◽  
Switching Losses ◽  
High Switching Frequency

The commercial mature gallium nitride high electron mobility transistors (GaN HEMT) technology has drawn much attention for its great potential in industrial power electronic applications. GaN HEMT is known for low on-state resistance, high withstand voltage, and high switching frequency. This paper presents comparative experimental evaluations of GaN HEMT and conventional Si insulated gate bipolar transistors (Si IGBTs) of similar power rating. The comparative study is carried out on both the element and converter level. Firstly, on the discrete element level, the steady and dynamic characteristics of GaN HEMT are compared with Si-IGBT, including forward and reverse conducting character, and switching time. Then, the elemental switching losses are analyzed based on measured data. Finally, on a complementary buck converter level, the overall efficiency and EMI-related common-mode currents are compared. For the tested conditions, it is found that the GaN HEMT switching loss is much less than for the same power class IGBT. However, it is worth noting that special attention should be paid to reverse conduction losses in the PWM dead time (or dead band) of complementary-modulated converter legs. When migrating from IGBT to GaN, choosing a dead-time and negative gate drive voltage in conventional IGBT manner can make GaN reverse conducting losses high. It is suggested to use 0 V turn-off gate voltage and minimize the GaN dead time in order to make full use of the GaN advantages.

scholarly journals Application of SHEPWM in Helicopter Transient Electromagnetic Based on the Subsection Control Approach

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Lihui Gao ◽  
Shengbao Yu ◽  
Chunxia Jiang ◽  
Nan Chen ◽  
Renhui Chen ◽  
...  
Keyword(s):  
Mirror Symmetry ◽  
Pulse Width Modulation ◽  
High Efficiency ◽  
Switching Frequency ◽  
Detection Accuracy ◽  
Switching Loss ◽  
Control Approach ◽  
Time Frequency ◽  
Transient Electromagnetic ◽  
Harmonic Elimination

Guaranteeing the quality of the transmitting current under low switching frequency conditions is the crucial point in the helicopter transient electromagnetic (HTEM) system which affects the efficiency and exploration accuracy. HTEM requires high efficiency and low switching loss of the inverter power supply due to the facts that HTEM uses air-launched and air-received measurement methods, and the power storage capacity of the airborne transmitting system is limited. Paradoxically, low switching frequency directly affects the transmitting waveform quality and thereby affects the detection accuracy. In this study, we present a semiperiodic mirror symmetry selective harmonic elimination pulse width modulation (SHEPWM) based on the subsection control approach to balance transmitting current quality and switching loss. In the SHEPWM method, the semiperiodic mirror symmetry SHEPWM nonlinear equations are established by the time frequency domain information of the inverter output voltage and resolved by the artificial neural network (ANN) algorithm to attain switching time sequence of desired transmitting current. The simulation and experimental results verify the effectiveness of the SHEPWM subsection control strategy, which can reduce the switching loss while ensuring the current waveform quality and detection accuracy.

scholarly journals Predictive Control Method Based on Adjacent Vector Confinement Technique for a Three-Phase AC-DC Matrix Converter with High Efficiency

Electronics ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 1535
Author(s):  
Eun-Su Jun ◽  
Hoang-Long Dang ◽  
Sangshin Kwak
Keyword(s):  
Control Strategy ◽  
High Efficiency ◽  
Control Method ◽  
Sampling Period ◽  
Matrix Converter ◽  
Current Control ◽  
Total Efficiency ◽  
Unity Power Factor ◽  
Switching Losses ◽  
The Cost

A model predictive current control method is proposed to reduce switching losses in an AC-DC matrix converter. In the proposed control strategy, several vectors are selected from among all possible switching vectors for a given location of the input current reference. The switching vector that minimizes the cost function is applied to the converter in the next sampling period. The principle of the proposed method involves clamping the selected switches to stop performing the switching operation to minimize the number of switchings in every sampling cycle. The total efficiency of the AC-DC matrix converter under the proposed strategy is 91.2% whereas that of the conventional strategy is 89.7%. In addition, unity-power-factor operation is guaranteed and smooth and sinusoidal waveforms are achieved. Finally, simulation and experimental results are demonstrated to confirm the validity of the proposed control strategy.

scholarly journals Design and Implementation of Improved High Step-Down DC-DC Converter for Electric Vehicles

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4206
Author(s):  
Dong-Ryeol Park ◽  
Yong Kim
Keyword(s):  
Electric Vehicles ◽  
High Efficiency ◽  
Low Voltage ◽  
Switching Frequency ◽  
Switching Loss ◽  
High Switching Frequency ◽  
Voltage Stress ◽  
Power Switches ◽  
Step Down ◽  
Secondary Side

An improved high step-down DC-DC converter for charging the batteries in an electric vehicle application is proposed in this paper. It adopts the topology of the conventional full-bridge converter, which has a coupled inductor current-doubler rectifier as the secondary side of the transformer. In addition, four power switches are driven using a phase-shifting technique. The proposed converter can achieve a high step-down voltage with low-voltage stress on the rectifier diodes. In addition, the coupled inductor current-doubler rectifier of the secondary side can reduce the ripple current and losses of the secondary side to achieve high efficiency. Furthermore, the proposed converter can overcome the drawbacks of the conventional full-bridge converter, such as switching loss caused by high switching frequency, duty-cycle loss, voltage stress, and numerous components, and can increase the efficiency with the soft-switching technique. A 600 W laboratory prototype of the proposed converter was manufactured. The results of the experiments performed with the prototype proved the effectiveness and validated the use of the proposed converter for better charging of electric vehicles.

scholarly journals High-Efficiency Design and Control of Zeta Inverter for Single-Phase Grid-Connected Applications

Energies ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 974 ◽  
Author(s):  
Woo-Young Choi ◽  
Min-Kwon Yang
Keyword(s):  
Single Phase ◽  
High Efficiency ◽  
Field Effect Transistors ◽  
The Body ◽  
Switching Frequency ◽  
Switching Losses ◽  
High Switching Frequency ◽  
Active Clamp ◽  
Synchronous Rectification ◽  
And Control

The conventional zeta inverter has been used for single-phase grid-connected applications. However, it has high switching losses to operate at high switching frequency in the continuous conduction mode (CCM). To address this drawback, this paper suggests a high-efficiency zeta inverter using active clamp and synchronous rectification techniques. The proposed inverter utilizes the active clamp circuit for reducing switching losses. The non-complementary switching scheme is adopted for not only clamping the switch voltage stresses, but also alleviating the circulating energy. In addition, the synchronous rectification is implemented for reducing the body diode conduction of power switches. By using the silicon carbide (SiC) metal oxide semiconductor field effect transistors (MOSFETs), the switching performance of the proposed inverter is improved. Its operation principle and control strategy are presented. A 220-W prototype has been designed and tested to evaluate the performance of the proposed inverter.

scholarly journals A New SVPWM Strategy for Three-Phase Isolated Converter with Current Ripple Reduction

Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4966
Author(s):  
Sheng Wang ◽  
Huaibao Wang ◽  
Hao Ding ◽  
Ligen Xun ◽  
Sifan Wu
Keyword(s):  
Electromagnetic Interference ◽  
Cost Effective ◽  
Modulation Scheme ◽  
Switching Frequency ◽  
Switching Loss ◽  
Matrix Converters ◽  
Switching Losses ◽  
Three Phase ◽  
Modulation Control ◽  
Current Ripple

Three-phase isolated matrix converters enable bidirectional power conversion and galvanic isolation, and they are suitable for widespread applications in industry. However, excessive DC-link current ripple not only increases the inductor loss and switching loss but also causes more electromagnetic interference and grid current distortion. Traditionally, increasing DC-link inductance or switching frequency can reduce the current ripple to a certain extent, but it is not cost-effective due to the bulky size of the inductor and higher switching losses. To address the above issue, optimizing the modulation control strategy is more attractive. This paper proposes a new SVPWM strategy to reduce the current ripple. First, the inherent limitation of the conventional modulation scheme is revealed. Then, the new optimal modulation scheme is proposed for the isolated matrix converters to reduce the current ripple without increasing the DC-link inductor or switching frequency. Moreover, the power density of the system is effectively increased. Finally, simulation in a MATLAB environment and a laboratory prototype of the isolated matrix converter have been built to verify the effectiveness of the proposed strategy.

scholarly journals Black Hole Algorithm for Sustainable Design of Counterfort Retaining Walls

2020 ◽  
Vol 12 (7) ◽  
pp. 2767 ◽  
Author(s):  
Víctor Yepes ◽  
José V. Martí ◽  
José García
Keyword(s):  
Black Hole ◽  
Sustainable Design ◽  
Retaining Walls ◽  
The Other ◽  
Trade Off ◽  
Construction Company ◽  
Geometric Variables ◽  
The Stability ◽  
The Cost ◽  
Black Hole Algorithm

The optimization of the cost and CO 2 emissions in earth-retaining walls is of relevance, since these structures are often used in civil engineering. The optimization of costs is essential for the competitiveness of the construction company, and the optimization of emissions is relevant in the environmental impact of construction. To address the optimization, black hole metaheuristics were used, along with a discretization mechanism based on min–max normalization. The stability of the algorithm was evaluated with respect to the solutions obtained; the steel and concrete values obtained in both optimizations were analyzed. Additionally, the geometric variables of the structure were compared. Finally, the results obtained were compared with another algorithm that solved the problem. The results show that there is a trade-off between the use of steel and concrete. The solutions that minimize CO 2 emissions prefer the use of concrete instead of those that optimize the cost. On the other hand, when comparing the geometric variables, it is seen that most remain similar in both optimizations except for the distance between buttresses. When comparing with another algorithm, the results show a good performance in optimization using the black hole algorithm.

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