The photovoltaic (PV) grid-connected power system in the residential applications is becoming a fast growing segment PV market due to shortage of fossil fuel energy and great environmental pollution. A new research trend generation employ parallel-connected configuration rather than series-connected satisfy safety requirements make full use generated power. How achieve high-step-up, low-cost, high-efficiency dc/dc conversion major consideration low output voltage with structure. limitations...

Single-phase voltage source transformerless inverters have been developed for many years and successful commercial applications in the distributed photovoltaic (PV) grid-connected systems. Moreover, advanced industrial topologies recent innovations published last few years. The objective of this paper is to classify review these contributions establish present state art trends inverters. This can provide a comprehensive insightful overview technology. First, generation mechanism leakage...

This paper proposes a novel sliding-mode observer (SMO) to achieve the sensorless control of permanent-magnet synchronous motor (PMSM). An is built according back electromotive force (EMF) model after EMF equivalent signal obtained. In this way, not only are low-pass filter and phase compensation module eliminated, but also estimation accuracy improved. Numerical simulations experiments with an 11-kW low-speed PMSM carried out. The results demonstrate that SMO can effectively estimate rotor...

To eliminate the common-mode leakage current in transformerless photovoltaic grid-connected system, an improved single-phase inverter topology is presented. The can sustain same low input voltage as full-bridge and guarantee to completely meet condition of eliminating current. Both unipolar sinusoidal pulsewidth modulation (SPWM) well double-frequency SPWM control strategy be applied implement three-level output presented inverter. high efficiency convenient thermal design are achieved...

A grid-connected photovoltaic (PV) power system with high voltage gain is proposed, and the steady-state model analysis control strategy of are presented in this paper. For a typical PV array, output relatively low, obligatory to realize function. The proposed employs ZVT-interleaved boost converter winding-coupled inductors active-clamp circuits as first power-processing stage, which can low array up dc-bus voltage. Accordingly, an accurate obtained verified by simulation experimental...

A mode-adaptive decentralized control strategy is proposed for the power management of a dc microgrid with multiple renewable distributed generators and energy storage systems. In presented solution, bus voltage signal used not only to enable sharing among different sources, but also designate operation modes facilitate seamless mode transitions. With this mechanism, greater freedom can be achieved than conventional droop scheme. More importantly, approach features fully self-disciplined...

In order to eliminate the common-mode (CM) leakage current in transformerless photovoltaic (PV) systems, concept of virtual dc bus is proposed this paper. By connecting grid neutral line directly negative pole bus, stray capacitance between PV panels and ground bypassed. As a result, CM can be suppressed completely. Meanwhile, created provide voltage level for ac generation. Consequently, required still same as that full-bridge inverter. Based on concept, novel inverter topology derived,...

A novel interleaved high step-up converter with voltage multiplier cell is proposed in this paper to avoid the extremely narrow turn-off period and reduce current ripple, which flows through power devices compared conventional boost applications. Interleaved structure employed input side distribute current, adopted output achieve a gain. The composed of secondary windings coupled inductors, series capacitor, two diodes. Furthermore, switch stress reduced due transformer function makes...

In this paper, the concept of frequency-coordinating virtual impedance is proposed for autonomous control a dc microgrid. This introduces another degree freedom in conventional droop scheme, to enable both time-scale and power-scale coordination distributed microgrid system. As an example, technique applied coordinating regulation hybrid energy storage system composed batteries supercapacitors. With effective frequency-domain shaping output impedances, battery supercapacitor converters are...

Thermo-sensitive electrical parameter (TSEP) approaches are widely employed in the junction temperature extraction and prediction of power semiconductor devices. In this paper, turn-off delay time is explored as an indicator a TSEP to extract from high-power insulated gate bipolar transistor (IGBT) modules. The parasitic inductor L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">eE</sub> between Kelvin emitter terminals IGBT module utilized...

For wireless power transfer (WPT) systems, communication between the primary side and pickup is a challenge because of large air gap magnetic interferences. A novel method, which integrates bidirectional data into high-power WPT system, proposed in this paper. The share same inductive link coreless coils. Power/data frequency division multiplexing technique applied, are transmitted by employing different carriers controlled independently. circuit model multiband system provided to analyze...

The concept of winding-cross-coupled inductors (WCCIs) and voltage multiplier cells is integrated to derive a novel interleaved high step-up converter in this paper. gain extended the switch stress reduced by WCCIs presented circuit, which minimizes peak current ripple power devices makes low-voltage MOSFETs with performance available output applications. Moreover, diode reverse-recovery problem alleviated leakage inductance WCCIs, reduces losses. Zero switching (ZCS) turn-on realized for...

Direct torque control is a variable-structure strategy with simplicity, fast response, and tolerance to motor parameter variation, which provides direct of stator flux electromagnetic by optimally selecting the inverter states in each sampling period. For five-phase drives, increased number voltage vectors offers greater flexibility optimizing selection states, thereby accomplishing more precise torque. Nevertheless, large means that elaborate complex criterion needed. The following two...

A zero-voltage switching-zero-current switching interleaved boost converter is proposed in this paper. An active circuit branch parallel with the main switches added and it composed of an auxiliary switch a snubber capacitor. By using topology, zero current turn-on voltage turn-off can be achieved reverse-recovery loss diode reduced. In addition, are transmission during whole transition. prototype rated at 1.2kW has been built to confirm effectiveness

In this paper, A single-phase improved active clamp coupled-inductor-based converter with extended voltage doubler cell is proposed for large-voltage conversion ratio applications. The secondary winding of the coupled inductor inserted into half-wave to extend gain dramatically and decrease switch stress effectively. By combining structure, disadvantage potential resonance between leakage inductance diode stray capacitor cancelled, unexpected high pulsed current in decreased due inherent...

In this paper, the built-in transformer voltage multiplier cell is inserted into each phase of conventional interleaved boost converter to provide additional control freedom for gain extension without extreme duty cycle. The only composed windings, diodes and small capacitors. And active switches are not required simplify circuit configuration. Furthermore, switch stress diode peak current also minimized due cells improve conversion efficiency. Moreover, there no reverse-recovery problem...

In this paper, the concept of built-in transformer voltage doubler cell is derived to generate an improved interleaved high step-up converter for distributed photovoltaic generation applications. The proposed composed three windings, two diodes, and capacitors. capacitors are charged discharged alternatively double gain. switch duty cycle turns ratio can be employed as controllable freedoms lift flexibly. power device stress also reduced improve circuit performance. Furthermore, active clamp...

A high-efficiency fuel-cell power-generation system with an active-clamp flyback-forward converter is presented in this paper to boost a 12-V dc voltage into 220-V 50-Hz ac voltage. The proposed includes high-step-up interleaved soft-switching and full-bridge inverter. front-end has the advantages of zero-voltage-switching performance for all primary switches, reverse-recovery-problem alleviation secondary output diodes, large voltage-conversion ratio, small input-current ripple....

In this paper, a built-in voltage gain extension cell is proposed to give universal topology derivation on next-generation high step-up converters for large conversion systems. Several improved single-switch with transformer multiplier are derived some advantageous performance, which includes extremely ratio, minimized power device stress, effective diode reverse-recovery alleviation, and soft-switching operation. The turns ratio of the can be employed as another design freedom extend gain,...

A basic cell with winding-cross-coupled inductors (WCCIs) and interleaved structure is proposed in this paper. family of DC-DC converters deduced from the cell, which suitable for high step-up or step-down conversions. The passive-lossless clamp scheme derived active to recycle leakage energy suppress voltage spikes caused by inductance. advantages boost converter WCCIs circuits are analyzed as an example. gain extended switch stress reduced minimize conduction losses. rectifier...

Multiport dc/dc converters are widely employed in hybrid energy generation systems to provide stable power key loads with high density. In this paper, the switch duty cycle and phase angle of interleaved as two control freedoms achieve decoupled voltage regulation within a certain operating range among different ports, which is referred pulsewidth modulation plus shift (PPAS) scheme. An bidirectional buck-boost converter full-bridge integrated together derive combined three-port for...

First, the limitations of conventional interleaved boost converters in high-step-up and high-output-voltage applications are addressed this paper. Then, a general derivation law nonisolated from their isolated counterparts is proposed studied to give universal solution for high-performance topology deduction. By employing direct energy transfer concept, family originated make turns ratio built-in transformer as another design freedom voltage gain extension. The derived have advantages large...