DC-DC Power Research Articles

PSO Training Neural Network MPPT with CUK Converter Topology for Stand-Alone PV Systems Under Varying Load and Climatic Conditions

Temperature and irradiance levels are two examples of environmental variables that affect the power value produced by photovoltaic panels. Therefore, in order to transfer the maximum power value from the PV panel to the load under varying climatic conditions, maximum power point tracking (MPPT) algorithms and DC-DC converter topologies are used. In this study, the performances of boost converter and CUK converter circuit topologies are investigated under variable irradiance and variable load conditions by using a neural network-based MPPT algorithm learning particle swarm optimization (PSO). As the first scenario, it is analyzed assuming that the temperature and irradiance values coming to the panel are constant. As the second scenario, the performance evaluation of the converter topologies according to the current, voltage and power parameters is made for the variable load situation. As the last scenario, the difference in the irradiance value coming to the panel depending on the sun's condition during the day has been examined. Canadian Solar CS6P-250P PV panel is used in the study. 50 kHz is selected as the switching frequency. According to the results obtained, it has been observed that the CUK converter circuit topology reaches the maximum power point faster than the boost converter circuit topology both in dynamic environmental conditions and load change, and the oscillation at this point is less. It is aimed to increase the performance of this method, which uses boost converter topology and MPPT in the literature, by applying CUK converter topology.

수소 연료 전지 기관차용 Partial Power DC-DC 컨버터 설계 및 검증

수소 연료 전지 기관차용 Partial Power DC-DC 컨버터 설계 및 검증

A Line Cycle Synchronous Rectification Strategy Based on Time-Domain Analysis for Single- Stage AC–DC LLC Converters

Synchronous rectification that is being widely used in high power and current DC-DC <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LLC</i> resonant converters to reduce conduction losses can be challenging in single-stage AC-DC <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LLC</i> converters with high output voltage levels (i.e., >200 V) where synchronous rectifier (SR) driving ICs cannot be used. In this paper, a simple AC line cycle synchronous rectification strategy with direct control by a cost-effective microcontroller unit (MCU) is proposed for single-stage AC-DC <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LLC</i> converters with high switching frequencies using wide bandgap devices (i.e., GaN or SiC). The SR gate pulse is generated based on the time-domain calculated conduction time, which is then switched <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</small> and <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> over the AC line cycle to avoid reverse power flow in light load conditions. The proposed strategy reduces the complexity of implementation over any adaptive online calculation or model-based methods that require powerful and expensive MCUs. First, the operation is briefly described followed by the time-domain analysis for AC operation. Next, the calculation and methodology behind the proposed AC line cycle SR driving strategy are discussed in detail. A scaled-down wide bandgap-based AC-DC <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LLC</i> converter prototype with a 250--400 V output voltage range is used with digital control implementation to validate the performance of the proposed synchronous rectification strategy. It is found that maximum efficiency of 98.1% can be achieved which is improved by around 0.5% over the conventional fixed conduction time method. Moreover, it is shown that the proposed method obtains the same efficiency levels as more complex adaptive SR driving approaches.

The Analysis of DCDC BUCK Circuit based on Arduino

With the development of the times, digitally controlled power supplies are becoming the trend of today's DC power supplies. This paper details a step-down circuit with Mosfet switch controlled by Arduino. This power supply and DC-DC adopts advanced semiconductor technology and digital control technology, featuring small size, light weight, simple and easy adjustment, high efficiency, wide voltage range and complete shutdown of zero-point adjustment. First, this paper details the structure, principle, and many features of the Arduino platform. Second, this paper explains the principle of BOOST circuit for boost and BUCK circuit for buck with equations and structure diagrams, and presents real-life applications. By reading this article, beginners will have a basic understanding of the use of Arduino and know what the exact principles of this circuit are, as well as circuit design and software programming ideas.

Parameter extraction and selection for a scalable N-type SiC MOSFETs model and characteristic verification along with conventional dc-dc buck converter integration.

Most silicon carbide (SiC) MOSFET models are application-specific. These are already defined by the manufacturers and their parameters are mostly partially accessible due to restrictions. The desired characteristic of any SiC model becomes highly important if an individual wants to visualize the impact of changing intrinsic parameters as well. Also, it requires a model prior knowledge to vary these parameters accordingly. This paper proposes the parameter extraction and its selection for Silicon Carbide (SiC) power N-MOSFET model in a unique way. The extracted parameters are verified through practical implementation with a small-scale high power DC-DC 5 to 2.5 output voltage buck converter using both hardware and software emphasis. The parameters extracted using the proposed method are also tested to verify the static and dynamic characteristics of SiC MOSFET. These parameters include intrinsic, junction and overlapping capacitance. The parameters thus extracted for the SiC MOSFET are analyzed by device performance. This includes input, output transfer characteristics and transient delays under different temperature conditions and loading capabilities. The simulation and experimental results show that the parameters are highly accurate. With its development, researchers will be able to simulate and test any change in intrinsic parameters along with circuit emphasis.

A novel auxiliary unit based high gain DC-DC converter for solar PV system with MPPT control

&lt;span lang="HR"&gt;Solar photovoltaic (PV) system becomes popular to generate the electricity in Asian region and helps to reduce the burden to utility. The power converter plays crucial role to interconnect with DC- grid. Traditional type power DC-DC converter can able to extract the maximum power from solar PV. However, most of the applications, it often fails to meet the voltage level of the DC bus and additional converter is required to boosting p the DC voltage. In order to overcome this drawback, this paper proposes a novel DC-DC converter to extract the maximum power from solar PV and helps to enhance the voltage level to meet the DC-bus. The PV and IV characteristics of practical solar PV cell and mathematical modelling have been done and implemented the same to proposed high gain converter. The maximum power point tracking (MPPT) algorithm and operation details are addressed and the detailed operation waveform of proposed high voltage gain DC-DC converter with mathematical evident is reported in this paper. The simulation study was carried out in the PSCAD/EMDTC software. From the measured results, it is investigated in further to validate the MPPT operation, gain values achievement and performance analysis of proposed converter. The corresponding explanations and results are presented in this article.&lt;/span&gt;

Real-Time Implementation of Sliding Mode Controller for Buck Power Converter using DSpace 1104

This paper deals an experimental validation of a nonlinear controller using a sliding mode control (SMC) with integral action for a dc-dc buck power converter. The main control objectives are: i) perfect regulation of inductor current with unknown load resistance variation, ii) and ensure the asymptotic stability of the closed-loop system. To this end, a SMC with integral action is elaborated. Using Matlab-Simulink software, numerical simulations are carried out to show the effectiveness of the proposed approach. Furthermore, using an experimental test bench, the real-time controller is developed based on the Dspace 1104 card in real time (RT). It was shown, using formal analysis, simulations and experiments, that the controller achieves all desired performances.

A Small Footprint Digital Isolator Based on CMOS Integrated Hall-Effect Sensor

Digital isolators have been widely used to protect low voltage electronics as well as human safety from high voltage surges. However, conventional isolation links occupy large chip areas. In this article, a novel small-size on- chip digital isolator for medium-bitrate application based on a CMOS integrated Hall-effect sensor is reported. With the proposed approach, the area of the transmitter coil is reduced to lower than 50% of conventional transformers. The architecture reduces the chip area in isolation amplifiers, power control units, DC-DC converters, and clock recovery circuits. It allows the integration of multichannel isolators using two custom integrated circuits with no post-processing. The tested prototype achieves a data transfer rate of 20 Mbps with above 12 kV/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{s}$ </tex-math></inline-formula> of common-mode transient immunity (CMTI). It has 900 V of continuous isolation working voltage, 27 ns propagation delay, and consumes 2.3 mA of static current.

Solar PV Fed DC Microgrid: Applications, Converter Selection, Design and Testing

In this research article, major applications which use solar PV fed DC microgrid for either their routine operation or gain additional advantages over existing electrical power architecture are elaborated. The role of power converters in interfacing the input with the required output is highlighted. The advantages of solar PV fed DC microgrid are demonstrated by designing and testing a non-isolated high gain high power (HGHP) DC-DC converter to meet the DC distribution voltage level. The proposed converter is synthesized by using hybrid combination of three-phase interleaved boost converter (IBC) with voltage lift technique along with coupled inductors (CIs) and voltage multiplier cell (VMC). The proposed concept is practically demonstrated and the adopted design techniques are validated using simulation and experimentation. The proposed converter with 60V/1.1kV, 100kHz and 3kW rating operates at 92.3% full-load efficiency under practical conditions. Due to the gain extension techniques adopted, the switches used in the proposed converter are subjected to a voltage stress which is only 36% of the output voltage. Due to interleaving technique, the input current ripple and the current stress on the switches are only 15% and 33% of the input current respectively. Key performance parameters of this converter are thoroughly investigated and benchmarked with some state-of-the art converters to appreciate the salient features of the presented converter. The ability to yield higher voltage gain at safe duty ratio, high power handling capacity, low voltage and current stresses on the power switches are the main advantages of the proposed converter.

Parameters Optimization of an Intermediate Frequency Isolated SiC Power DC-DC Converter

To improve the lightweight level of auxiliary converters for urban rail vehicles, full SiC intermediate frequency auxiliary converters have become a trend. Aiming at its core component, a full SiC intermediate frequency isolated DC-DC converter using Boost + LLC topology is studied in this paper. The working principle and characteristics of the converter are analyzed in detail. Based on the operating characteristics of the LLC resonant converter and the realization mechanism of soft switching, an optimization design method of the resonant parameters is proposed, which can make LLC resonant converters exhibit the characteristics of DC transformers and realize soft switching in the full load range. Considering the power losses of the converter and the voltage stress of SiC MOSFET, the design method of the intermediate bus voltage is given. Finally, the correctness of the parameter design method is verified by simulation and experiment, and the performance of the full SiC intermediate frequency isolated DC-DC converter is analyzed. When the input voltage is 1500V and the output power is 15kW, the efficiency of the converter reaches 96.21%. Compared with the Si intermediate frequency isolated DC-DC converter, the power density is improved by 80.62%.

A highly consistent and proficient class of multiport dc-dc converter based sustainable energy sources

ThePhotovoltaicsystem(PV) systems are reliable Renewable Energy Sources (RES) because to their efficiency under high irradiation conditions, low maintenance, and low pollution. Effective processes generate steady power. This new programme determines the dynamic performance of this technology's application to conduct a thorough feasibility utility grid is determined under different operational circumstances. However, integrating renewable energy into the alternating current system has challenges including voltage increases, synchronisation, and protection. With the DCDC converter, the power distribution system will be more reliable. The RES voltage level and storage needed by the static power DCDC converter must be maintained to preserve grid synchronisation. Because static converters are simple, they need a separate converter for stabilisation, increasing the circuit size. Compact size, centralised control, and energyefficient energy management are important features of Multiport Converters (MPC). The microgrid needs a backup battery to offset the intermittent nature of renewable energy sources. To ensure safety, isolation between the source and the load is required. Storage devices need a twoway power channel. An independent multiport converter is needed for the connected operation of the battery equipment and the utilisation of various renewable energy sources. The benefits of higher power density and separation of the nonisolation circuit allow for a smaller total circuit size. This paper summarises the multiport DCDC converter design for RES harvesting in a DC microgrid and makes research suggestions.

Systematic and Novel Approach to Modeling, Analysis and Control of Grid Tied PV Power Supply System Using Integral State Feedback Control and State Observer

Today, the share of global energy mix related to renewable energy technologies is rising drastically. The main reason behind this new trend is associated with many global challenges. Sustainable development, climate change and the need for alternative sources of energy are some of the driving forces and also reason’s powering technological innovation in energy sector. However, in order to achieve climate change goals, technological advancements of green energy must be accelerated. In this paper, a grid connected three phase photo-voltaic power supply system using integral state feedback control and state observer has been examined and proposed. Mathematical modeling of main components of the PV system including the power grids, solar panels, DC-DC converter and DC-AC inverter are performed. In addition, in order to increase the efficiency of the proposed system a maximum power point tracking algorithm using fuzzy logic control is introduced. Finally, simulation results using MATLAB shows the effectiveness of the proposed solution. Keyword: PV system, green energy, DC-DC converter, DC-AC converter, Maximum power point tracking.

Investigation into the Parameters of Driver Circuits for Power Electronic and DC-DC Converters

The paper focuses exclusively on the analysis of the simulation software and the main parameters of the driver circuits for power electronic converters. A mathematical model of the driver circuit in the Matlab Simunink software environment has been created. This model enables the analysis of the process of frequency formation through the boostrap capacitor and examines the interaction between the protection of the scheme at , and the other digital blocks in the circuit. Considered, additionally, are the basic physical processes behavior of a driver with a similar structure in Infineon designer.

Fault identification in a grid connected solar PV system using Back propagation Neural Network

Albeit the government buoy up the penetration of renewable energy sources (RES) particularly solar photovoltaic (PV) system, the dependency on fossil fuels is still growing. The power generation using solar PV system may enhance when the enactment of solar PV system is improved. The faults occurred in the system is an important performance degradation factor. Incessant studies have been performed to identify and mitigate the faults. Currently, several smart techniques are utilized to identify the faults rapidly. In this study, Back Propagation Neural Network (BPNN) has been implemented to identify the faults. The output power get degraded when the faults happened in source side, Maximum Power Point Tracking (MPPT), DC-DC converter, rectifier and grid. The investigations has performed on 100 kW solar PV system using Matlab. The outcomes imply that the proposed method has detected the faults quickly, economically and effectively.

Optimal Control With Maximum Cost Performance Measure

Optimal control of discrete-time systems with a less common performance measure is investigated, in which the cost function to be minimized is the maximum, instead of the sum, of a cost per stage over the control time. Three control scenarios are studied under a finite-horizon, a discounted infinite-horizon, and an undiscounted infinite-horizon performance measure. For each case, the Bellman equation is derived by direct use of dynamic programming, and the necessary and sufficient conditions for an optimal control are established around this equation. A motivating example on optimal control of dc-dc buck power converters is presented.

Construction of a Simple USB Powered LED Light Source for Illuminating Optical Microscopes

Tungsten and halogen lamps are normally used for microscope illumination. However, if there is an electrical fault in any of these lamps, extra money to purchase a new one and the sacrifice of a long time for its arrival may be required to get the lamp replaced, especially in some developing countries. The aim of this study therefore is to develop a cheap and easily obtainable light source, built with Light Emitting Diodes (LEDs) to replace a faulty tungsten or halogen lamp. The LEDs are cheap to buy, easily available and operate at a much lower voltage. A light source, using LEDs, was designed and constructed to fit easily into the space previously occupied by the tungsten or halogen lamp. An integrated switching low power DC-DC converter, having a microcontroller unit at its heart and powered from a 5 Volt source, was also constructed to control the LED light source. It was observed that the contrast of the sample image obtained with the halogen lamp was reproduced by the LED light source. In this study, a replacement LED based light source for illuminating optical microscopes was constructed, and it gave a reasonable result compared to that obtained by using the halogen lamp. This work will be very useful in those places where it may be very difficult to get a quick replacement halogen or tungsten lamp or where electric power is not always available.

GaN Power Integration for High Frequency and High Efficiency Power Applications: A Review

High frequency and high efficiency operation is one of the premier interests in the signal and energy conversion applications. The wide bandgap GaN based devices possess superior properties and have demonstrated exceeding performance than Si or GaAs devices. In order to further exploit the potential of GaN electronics, monolithic power integration is proposed. Firstly, this paper discusses the structure and properties of GaN power devices to explain the choice of lateral integration in the view of GaN power ICs. Then the state-of-the-art performance of GaN power integration in two major application areas is reviewed, which are the microwave power amplification and DC-DC power conversion. The GaN power integration technologies in MMIC platforms are summarized in terms of the gate length, operation frequency and power added efficiency of ICs. On the other hand, the smart GaN power IC platforms have boosted the development of DC-DC power converters. Demonstrations of high frequency (>1 MHz) and high efficiency (>95 %) converters with various kinds of integration technology and topology are reviewed. Lastly novel integration schemes and methods are introduced to stimulate new thoughts on GaN power integration road.

A Data-Driven-Based Fault Diagnosis Approach for Electrical Power DC-DC Inverter by Using Modified Convolutional Neural Network With Global Average Pooling and 2-D Feature Image

A novel convolutional neural network namely the modified CNN-GAP model is proposed for fast fault diagnosis of the DC-DC inverter. This method improves the model structure of the traditional CNN by using a global average pooling layer to replace the fully connected layer of 2~3 layers. The improved CNN-GAP method mainly contains an input layer, a feature extraction layer, a global average pooling (GAP) layer, and a Softmax output layer. Firstly, the raw 1-D time-series data directly input into the input layer of the established CNN-GAP diagnosis model. The 2-D feature maps are reconstructed in the input layer. Secondly, the representative features are automatically extracted from the 2-D feature maps by using multiple convolutional layers and pooling layers. Thirdly, the dimension transformation and size compression of the output image of the feature extraction layer is completed by the GAP layer. Finally, the fault diagnosis result of the DC-DC inverter is automatically output in the Softmax output layer. The proposed method is used for diagnosing the open-circuit fault of the IGBT in the isolated DC-DC inverter. The proposed method is more accurate and effective than other mainstream intelligent diagnosis methods including the SVM, KNN, DNN, and traditional CNN. The experiment results show that the diagnostic accuracy is up to 99.95%, and the testing time can reduce by more than 15%. The improved CNN-GAP method could greatly reduce the model parameter quantity of the traditional CNN more than 80%, which is more suitable for rapid fault diagnosis in electronic devices.

Multiport energy gateway

Medium-voltage-direct-current collection and distribution grids are being considered for emerging applications, and require enabling power electronic technologies. Medium-voltage high power DC-DC converters are one of the solutions that will play an important role in future energy systems. This study presents a novel bidirectional multiport power electronic converter, interfacing medium-voltage and low-voltage distribution grids while integrating distributed energy storage elements, such as batteries and super-capacitors. The multiport energy gateway concept is based on a modular input-series output-parallel topology includes medium frequency transformer for the galvanic isolation, and combines open-loop and closed-loop operated converter stages. Comprehensive converter design aspects and operating principles are presented and discussed considering representative cases of studies. The validity of the approaches is proved by simulation and experimental results obtained on a small scale prototype.

Development of interactive multimedia-based learning media on power electronics courses through e-learning

This research aims to develop interactive multimedia-based learning media that can improve student understanding of the material DC-DC converters and AC-AC converter. The methods used to research and development with the Instructional Development Institute (IDI) model. The subject of the study was a student of electrical engineering education. Data-collecting instruments in the form of a questionnaire. Analytical techniques descriptive data to describe the validity, practicalities, and effectiveness of interactive multimedia-based learning media. The results of this study indicate that interactive multimedia-based learning media on subjects of electronics material power DC-DC converter and AC-AC converter is valid, practical, and effective.