DC Connector Research Articles

Vehicle-to-Grid Market Readiness in Europe with a Special Focus on Germany

Vehicle-to-grid means that electric vehicles are charged when electricity is plentiful and discharged when it is scarce. New battery-electric vehicles have an energy capacity above 60 kWh installed and practically always have a DC connector. With over 1 million of such vehicles in Germany alone already, the flexibility potential to balance out fluctuating renewable generation or compensate for grid constraints is large. While many actors are working to enable this market, the readiness of hardware and regulations as well as the potential volume are hard to grasp. This paper provides an overview of these factors for Europe with a special focus on Germany. We find that some countries started to implement regulatory frameworks but none are ready yet. Issues include taxation, the fulfillment of grid codes, and the lack of smart meters. In terms of vehicles, 25 manufacturers with bidirectional charging ability were identified, but most vehicles were only used in field tests or operate in island mode. In terms of charging infrastructure, the picture is brighter with at least 20 manufacturers that offer DC bidirectional charging stations and 2 offering an AC variant.

Construction of a 12V Standalone Solar Powered DC fan for Solar Energy Utilization

This project was embarked on construction of a 12 volts standalone solar powered DC fan for solar energy utilization using constructed DC fan, solar photovoltaic panel illuminated by solar radiation, 12 volts DC battery and connectors. After construction of DC fan, measurements were carried out using 25 volts adjustable DC regulated power supply system to feed in variable voltage and determine the output voltage and the speed of fan at different distance using hand held anemometer. The rate of blowing air of air determined at different input voltage and distance determines its performance ability. Therefore, the performance ability of DC fan determined upholds its utilization at home and office, both in urban and rural areas where grid electricity is not regular or unavailable.

Integrated Busbar Design for Stray Inductance and Volume Reduction in a High-Power SiC Traction Inverter

<div class="section abstract"><div class="htmlview paragraph">This paper presents a compact, partially laminated busbar design to connect the DC-link capacitor, high-voltage DC (HVDC) connector, and power module using a single integrated busbar. The proposed busbar design is designed for a high-power and high-voltage Silicon Carbide (SiC) traction inverter. The proposed solution eliminates the need for using separate busbars: one for the connection between the HVDC connector and the DC-link capacitor, and the other one between the connection of the DC-link capacitor and the power module. Incorporating two busbars in a single traction inverter increases the total volume of the inverter and the parasitic components. Thus, the main design goals in this paper are minimizing the parasitic inductances, increasing the power density, and achieving a uniform current distribution across the capacitor cores. Additionally, the compact busbar design allows a reduction in the parasitic resistance compared to two separate busbars and, hence, it reduces the power loss. The voltage overshoot and maximum allowable stray inductance of the busbar are investigated in detail. Current density and its effect on the busbar temperature rise are analyzed using 3D finite element analysis.</div></div>

SISTEM INFORMASI MANAJEMEN PEMASARAN, PENJUALAN DAN DISTRIBUSI PRODUK CCTV (STUDI KASUS : TOKO KARYA JAYA SECURITY)

Toko Karya Jaya Security is a company engaged in the sale of CCTV complete with Indoor or Outdoor Cameras, Monitors, DVR, Cables, Seagate Hard Drives, Power Supply, BNC Connectors and DC Connectors, Spare Parts, Fingerprint, Running Text and Video Tron. In the business of selling CCTV, Toko Jaya Security has not used technology as a sales or promotion medium to expand the product marketing process. For now, the business process carried out by Toko Karya Jaya Security is still done manually both in promoting products, sales between customers who still come directly to the store to order or buy CCTV products, and record transactions that are done manually. The purpose of this research is to design and build a CCTV Product Marketing, Sales and Distribution Management Information System that is used to help Toko Karya Jaya Security in expanding marketing and increasing sales of CCTV products, to making reports quickly and accurately. Data collection techniques used in this study are interviews, literature review and documentation. The data source was obtained from the head of Toko Karya Jaya Security. Marketing, Sales and Distribution Management Information System for web-based CCTV products is built using programming languages such as PHP and HTML. Database using MYSQL. The interface design is made using the Mockplus application. This system is tested using ISO 25010. This measurement is based on 6 main characteristics of ISO 25010, namely Functional Suitability, Reliability, Performance Efficiency, Usability, Maintainability and Portability. From the calculations carried out using the Likert scale, the result is 83.86%. So it can be concluded that the design of this system is declared very good to use and feasible to implement.

RETRACTED: Applications of internet of things (IOT) to improve the stability of a grid connected power system using interline power flow controller

Abstract Using Internet of Things (IoT) technology in the clever network is an essential method to fast active the information of control Grid-system. Also, the grid system is valuable aimed at the compelling administration of the power framework foundation. This paper deals with a logical approach to design an Interline Power Flow Controller (IPFC) for a grid-connected several-line power scheme to improve the scheme strength and to improve the congestion management in a grid by considering the power flow among the multi-line, IPFC goes to a sequence of paying flexible alternating current transmission system (FACTS) device and it takes the capability toward control the power stream in multi-line transfer organizations.. The Distributed Interline Power Flow Controller involves the series and shunt converters in different transmission lines that are between related utilizing a run of the DC connector. In the transmission line, is the IPFC considered for the compensation and control of power flow in a multi-line transmission system. Every converter can give plan reactive compensation off its line also with the frequency. As the converters can exchange dynamic power through their essential DC interface, it can similarly give a frequency of the current. The highest objective is to improve the power flow in transmission lines and also to maintain the system stability at the buses, and it is achieved by developing an IPFC controller along with genetic algorithm. A Simulink model of an Interline Power Flow Controller based several-machine framework alongside genetic algorithm is developed, and its outcomes were compared with the conventional scheme for tuning the proposed controller to confirm their effectiveness and robustness. It also explains the optimization technique in multi-machine power system with an IPFC using GA. Concentrated on the normal for the development and improvement of the brilliant matrix, this paper presented the use of IoT in web-based checking framework of grid-connected power system using IOT.

A Grid-Connected Smart Extendable Structure for Hybrid Integration of Distributed Generations

In this paper, a novel grid-connected smart and plug-and-play type extendable structure named unified multiport power electronic converter (UMPEC) for hybrid integration of distributed generation (DG) systems is presented. The proposed structure contains two types of connector ports. The first one is a set of AC connectors, which can be easily used to connect different types and numbers of AC-based DGs along with grid and loads. The second one is a set of DC connectors, which can interface DC-based DGs and storage units. Compared with the conventional and recently invented multi-stage power electronic topologies, the proposed structure enjoys less number of power electronic components, compactness, and plug-and-play capability of integrating AC and DC-based DGs. Considering shared components between different ports and their imposed boundaries on the operation of the UMPEC, a modified sequential space vector modulation is addressed, which makes it possible to control different ports independently, without compromising with maximum power harnessing from individual sources, which is another salient feature of this work. The proposed structure operation and performance is verified using a three DC and two AC connectors version, where wind and photovoltaic systems are independently interfaced to the grid.

Correlation between current-voltage characteristics and DC field grading for dielectric liquid used in wet-mate DC connector

Subsea DC transmission and distribution system is a promising technology for powering subsea oil and gas fields with high power, long distance and ultra-deepwater depth. In subsea DC transmission and distribution, wet-mate (WM) connectors are considered as a challenging component due to the complicated electrical field distribution in the insulation system and harsh undersea wet-mating environmental conditions. In order to design reliable liquid insulation systems for subsea connectors, it is essential that the behavior of the DC-stressed liquid insulation be fully characterized for thorough understanding. In this paper, liquid conduction phenomena in synthetic ester oil are studied using the current-voltage characteristics and electric field distribution mapping based on the Kerr electro-optic effect. The correlations between the current-voltage characteristics and DC field grading among different electrode gaps and oil types were analyzed. The experimental results suggest that for applied voltage less than the saturation voltage (V s ), the conduction is dominated by ion dissociation in the bulk oil. Correspondingly, the liquid conduction is ohmic and with formation of heterocharges around the contacts giving symmetrical field distribution. At applied voltage higher than saturation voltage (V s ), this bulk conduction will transit to extrinsic dominated conduction with carriers injected through liquid-electrode interfaces. Under such carrier injection, the corresponding field distribution becomes asymmetrical. In addition to the laboratory experiments, computer simulations with an ion drift-diffusion conduction model taking into account electrode injection were carried out to validate the experimental field distribution at different electrode gaps. The effect of electrode material on the electric field distribution in the oil is investigated and implications for wet-mate connector design principles are presented.

A thermo-electrodynamic electric field dependent molecular ionization model to design electrical insulation system of HVDC wet-mate connectors under transient conditions

A powerful engineering software tool is elaborated to design proper dimensions/ systems/materials in a wet-mate DC connector under transient conditions. By using this tool, designers can examine various preventive measures to avoid streamer growth or limit it to only glow discharge in the oil portion of a wet-mate DC connector. In this regard, for a compact design of a wet-mate DC connector envisaged in this paper four mitigation methods including 1) using a dielectric solid covering the front portion of the moving contact, 2) increasing the relative permittivity of the dielectric solid, 3) using the dielectric oil with molecular constituents having high molecular ionization potentials, and 4) increasing the radius of curvature of the edge are evaluated.

The influence of magnitude and rise time of applied voltage and the type of oil on streamer growth in a wet-mate DC connector

For the safe design and operation of wet-mate (WM) DC power connector, a time-dependent full thermo-electrodynamic model comprised of Poisson's equation, three charge continuity equations-one each for the positive and negative ions and one for the electrons-, and a thermal diffusion equation is developed to study the streamer initiation and propagation in the oil portion of a WM DC chamber. The electric field dependent molecular ionization mechanism accounts for the source term for free charge carriers, and positive ion/electron recombination, positive/negative ion recombination and electron attachment represent sink terms in the oil section. The solid portion of the WM DC connector is modeled as a perfect insulator. Considering a needle-sphere electrode geometry with electrodes covered by a dielectric solid and oil enclosed by the dielectric solid, it is approached the complicated solid-liquid insulation system envisaged in a WM DC connector after mating. By using the model, the influence of three parameters including magnitude and rise time of applied voltage as well as the type of oil on streamer initiation and propagation is investigated. It is found that the shorter rise time the more prominent streamer growth in the oil portion. For oil comprising only aromatics, an electric field magnitude larger than about 2×108 V/m is needed to propagate streamers, while this value for the oil comprising naphthenics/paraffinics will be exceeding 4×108 V/m.

A thermo-electrodynamic electric field dependent molecular ionization model to realize positive streamer propagation in a wet-mate DC connector

Complete subsea factory concept, an equivalent of the full topsides processing facility to be operated on the seabed, is envisaged to power longer, deeper and colder subsea oil and gas fields in the future. This concept has been envisioned through a modular stacked subsea DC transmission and distribution system whose subsea umbilical cables and electrical power component on the seabed can be interfaced with each other by wet-mate (WM) DC connectors. Laboratory and theoretical investigations have been carried out to assess various electrical insulation systems and electrode geometries for a WM DC connector which should operate in the steady state as well as switching transients in a corrosive environment for high reliability and minimum maintenance in its lifetime. In this paper, the electrical insulation performance of a needle-sphere electrode geometry defined by IEC 60897 under a positive step voltage is studied. To approach the complicated solid-liquid insulation system envisaged in a WM DC connector after mating, the electrodes are covered by a dielectric solid and oil is enclosed by the dielectric solid as well. A full thermo-electrodynamic electric field dependent molecular ionization Multiphysics model was developed for the simulation of streamer initiation and growth in the oil while dielectric solid is modeled as a perfect insulator. It is shown that stabilization methods, mesh strategies and time step have a great influence on simulation results and guidelines to choose them properly are presented. Based on simulation results, it was found that the higher relative permittivity of the solid insulation the slower streamer propagation in the oil and the less electrical stress on the solid insulation.

Contactless DC Connector Based on GaN LLC Converter for Next-Generation Data Centers

An inductively coupled contactless dc connector has been proposed for the next-generation 380-V dc distribution system in data centers. A LLC resonant dc–dc converter topology with gallium nitride (GaN) power transistors has been applied to realize the short-distance highly efficient contactless power transfer. A prototype of a 1.2-kW 384- to 192-V connector has been fabricated and the conversion efficiency of over 95% with the power density of $8.1 \hbox{W}/\hbox{cm}^{3} $ has been confirmed experimentally under 1000-kHz operation. The design consideration has been carried out and the potential to achieve $10.0 \hbox{W}/\hbox{cm}^{3} $ has been also shown taking the feature of the GaN power device and the characteristics of the magnetic core material for the transformer into account. The contactless dc connector integrates the functioning of an isolated dc–dc converter into a connector for space saving, and the dc current can be cut off without arc because of the inductive coupling. The proposed connector contributes to realizing a highly efficient, space saving, and reliable future 380-V dc distribution system.

A Silicon Photonic Integrated Packaged Coherent Receiver Front-End For Soft-Decision Decoding

In this paper, a packaged integrated coherent receiver and optical front-end for soft decision based on 25 Gbaud/s quadrature phase-shift keying (QPSK) is investigated for on-chip applications. The front-end consists of a 90° hybrid, balanced photodetectors, and unbalanced couplers monolithically integrated in a CMOS compatible silicon-on-insulator technology. The silicon photonic device is packaged onto a ceramic substrate with RF and dc connectors. The proposed front-end is an example of integration of system on chip. The integrated solution is able to provide 6.2 dB performance improvements over uncoded system without error correction. The front-end outperforms optical system with hard-decision forward error correction by 2.2 dB at the BER of 10−7.

On Reconfigurable Machines and Reconfigurable Assembling Machine for DC Connector Plug

Reconfigurable machines are essential components to implement a reconfigurable manufacturing system. This paper focuses on one of reconfigurable machines: reconfigurable assembling machine. A reconfigurable automatic assembling machine for DC connector plug is designed. It can be divided into the basal module and the changeable module. The same basal module with different changeable module can be assembled into different special assembling machines for DC connector plug with different shape, size or number of electrodes.