This paper proposes a four-degrees-of-freedom modulation scheme to mitigate the conduction and switching losses in dual-active-bridge (DAB) series-resonant converter. Under wide-range variations voltage gain output current, increased reactive power root-mean-square tank current can contribute significantly loss DAB converter, while occurrence of hard leads an device stress. The proposed utilizes internal, external phase shifts, frequency as parameters achieve zero power,...

Bidirectional ac–dc wireless power transfer (WPT) converters are widely used in grid-connected electric vehicle systems for grid-to-vehicle and vehicle-to-grid applications. They usually apply a two-stage topology with bidirectional factor correction converter dc–dc WPT converter. Such cannot achieve high efficiency low cost. Recently, single-stage matrix have been proposed. However, the matrix-converter-based topologies do not utilize remarkably lower count of switches generate large...

LEDs must be externally driven by power sources to emit light. One problem associated with driving is its inherent nonlinear relation between the emission intensity and forward current. Thus, light output obtained from an LED strongly dependent on actual current waveforms employed drive it. It found that dc produces surpasses all other techniques including commonly used pulse-width modulation (PWM) technique. On hand, for dimming function, it PWM technique offers greater flexibility in...

The significant improvements recently achieved in LED technology terms of lifetime, luminous efficacy, power rating, and color property render one the most promising candidates to replace conventional light sources various residential industrial applications. rapid advancement device characteristics has simultaneously stimulated interests developing efficient drivers with optimized control circuitries. two techniques currently employed drivers, namely amplitude-mode pulsewidth modulation...

Hard-switching-induced switching loss can contribute significantly to the power of an isolated bidirectional dual-active-bridge (DAB) dc-dc converter operating at high frequency. An LC-type series resonant DAB based on a switch-controlled-inductor (SCI) is proposed mitigate arising from hard under wide-range variations in output voltage and current. Zero-voltage achieved primary side (high voltage), while secondary (low zero-current preferred reduce excessive ringing due circulating current...

Both conduction loss and switching can contribute significantly to the overall power of an isolated bidirectional dual-active-bridge series-resonant dc-dc converter (DABSRC) operating at high frequency. To achieve soft minimum-tank-current operation under wide-range variations in output voltage current, a switched-impedance-based DABSRC is proposed. Minimum-tank-current aims reduce arising from circulating current low voltage, high-current side DABSRC. Full-range achieved all switches, thus,...

The aim of this article is to introduce a novel Circle Search Algorithm (CSA) with the purpose obtaining precise electrical model proton exchange membrane fuel cell (PEMFC). Current-voltage and current-power curves are used characterize performance PEMFCs. A nonlinear seven unknown parameters describe these polarization curves. Estimating critical issue because they influence dynamic analysis cells in variety applications such as transportation smart grids. suggested method based on...

For process control in engineering applications, the fewer coding lines of optimization algorithms, more applications there are. Therefore, this work develops a new straightforward metaheuristic algorithm named propagation search (PSA), stirred by wave voltage and current along long transmission lines. The mathematical models are utilized modeling PSA, where agents. constant line is parameter for exploitation exploration PSA. After that, robustness PSA verified using 23 famous testing...

Most commercial white LEDs are made from nitride-based blue coated with yttrium aluminium garnet phosphor, which produce spectra that shift in opposite directions under the influences of drive current and junction temperature changes. This property gives rise to different emitted spectra, hence chromaticity properties, when LED is driven/dimmed by waveforms. By using a sample, LUXEON K2, effects on changes coordinates studied experimentally. The impact dc, pulse width modulation (PWM),...

This paper presents a unified approach to controlling the white color point of red/green/blue (RGB) light-emitting diode (LED) existing in all aging states. In contrast conventional control systems where average driving currents primary-color LEDs can become saturated when have undergone prolonged aging, which causes resulting go out regulation, proposed method avoids this problem by adjusting set points predefined threshold current is reached one or more LEDs. It shown that effectively...

Two-stage single-phase inverter system has found many applications in distributed generators and grid-connected systems. However, the existence of double-line frequency ripple on dc-bus voltage due to inverter's operation given rise some design reliability issues. Some these are degradation quality output shortening capacitor's lifetime. The problem is rooted controller front-end dc-dc converter, which often designed based a simplified mathematical model converter that fails account for...

This paper proposes a reconfigurable dual-active-bridge (DAB) converter that is capable of switching between two structures for enhancing its performances at different output power levels. For 50%-100% load, the operates in full-bridge mode and achieves soft-switching all switches independently input-to-output voltage ratio. Below 50% reconfigured to operate half-bridge reduced circulating current improved light-load efficiency while maintaining desired characteristic mode. The achievement...

Three-diode model (TDM) of photovoltaic (PV) cells is more accurate that includes most the optical and electrical losses PV module. However, nonlinearity parameters this TDM are higher, which make it complex challengeable model. This article utilizes an efficient algorithm called Circle Search Algorithm (CSA) for modeling modules. The CSA inspired by circle's well-known geometrical properties perpendicular relationship between its radius tangent line. other four algorithms applied to...

It is increasingly difficult to identify complex cyberattacks in a wide range of industries, such as the Internet Vehicles (IoV). The IoV network vehicles that consists sensors, actuators, layers, and communication systems between vehicles. Communication plays an important role essential part IoV. share deliver information based on several protocols. Due wireless vehicles, whole can be sensitive towards cyber-attacks.In these attacks, shared with malicious or bogus user, resulting attacks...

Single-phase ac–dc wireless power transfer (WPT) converters are widely used in grid-connected systems, such as electric vehicle chargers. Traditional two-stage topology with an factor correction (PFC) rectifier stage and a dc–dc WPT converter cannot achieve the highest overall efficiency lowest production cost. Moreover, two separate controllers required. Recently, single-phase single-stage front-end boost bridgeless PFC was proposed to overcome drawbacks of topologies. However, diodes still...

This paper investigates the design and implementation of virtual-output-impedance shaping on an inverter-loaded, fuel-cell-battery-powered dc-dc converter system for achieving near-ripple-free dc bus voltage regulation. The method is based insertion a second output-voltage feedback loop as can be inferred from Mason's gain formula. Three basic modes (proportional, derivative, integral) are discussed closed-loop output-impedance characteristics due to each them analyzed in detail with their...

For power converters used in renewable energy systems, output-impedance design has become an important consideration for minimizing the impacts of low-frequency harmonic current on lifetime ripple-sensitive sources such as fuel cells and photovoltaic cells. In literature, various methods are proposed to tackle this issue but they frequently treated isolation from each other specific systems being discussed. paper, a systematic derivation four basic modes shaping method is presented. These...

The increasing penetration of distributed renewable generations has given rise to a novel energy management mechanism, peer-to-peer (P2P) trading. concept Energy Internet (EI) is proposed as new system framework facilitate P2P trading where all electrical devices are interconnected via routers (ERs). A proper market clearing approach required coordinate decentralized decision making in for demand-supply balance and feasible end-to-end delivery. In this paper, mechanism considering path...

Multistring arrays of LED are increasingly used for high-luminance lighting applications. The parallel connection multiple strings, however, gives rise to the issue current balancing between as a common voltage applied them does not guarantee an equal sharing due manufacturing spread in electrical properties. In relation need balancing, emergence AC-LED has enabled direct driving with ac voltage/current, and capacitors, whose impedance designed dominate over equivalent resistance string,...

Current imbalance is a major problem in multistring LED lighting systems. Significant research efforts have been directed to solve the by either an active or passive approach. However, view of some system requirements other emerging applications, independent control different strings getting more important obtain desirable brightness and/or color spectrums. The existing and approaches their limitations perform current balancing simultaneously, thus posing another great challenge for design...

Power-factor preregulators are commonly used in electronic equipments for minimizing the injection of current harmonics into mains power line. However, bandwidth conventional usually configured to be very small order achieve near-unity factor, and this inevitably gives rise poor dynamic response. Ripple estimation/cancellation method is eliminate double-line frequency component from sampled output voltage before it propagates control loop, hence, requirement not mandatory. The existing...