This paper investigates the capacitor-current-feedback active damping for digitally controlled LCL-type grid-connected inverter. It turns out that proportional feedback of capacitor current is equivalent to virtual impedance connected in parallel with filter due computation and pulse width modulation (PWM) delays. The LCL-filter resonance frequency changed by this impedance. If actual higher than one-sixth sampling (f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...

Capacitor-current-feedback active damping is an effective method to suppress the LCL-filter resonance in grid-connected inverters. However, due variation of grid impedance, frequency will vary a wide range, which challenges design capacitor-current-feedback coefficient. Moreover, if equal one-sixth sampling (f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</sub> /6), digitally controlled LCL-type inverter can be hardly stable no matter how...

Due to the significance of extracting grid voltage information, synchronization system plays an important role in control grid-connected power converters, and various schemes have been proposed. This paper adopts complex-vector-filter method (CVFM) analyze systems. With this method, pairs scalar signals, for example, α- β-axis components stationary α-β frame, are combined into one complex vector. As a consequence, systems can be described with transfer functions, which is very convenient...

This paper investigates the feedforward schemes of grid voltages for a three-phase <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LCL</i> -type grid-connected inverter. The full-feedforward functions are derived stationary α- β frame, synchronous xmlns:xlink="http://www.w3.org/1999/xlink">d</i> - xmlns:xlink="http://www.w3.org/1999/xlink">q</i> and decoupled frame-controlled inverters. mainly consist three parts which proportional, derivative,...

The grid voltage full feedforward scheme is an effective method to improve the injected current quality of grid-connected inverter. However, due digital control delay, suppression harmonics weakened, and inverter output impedance has additional negative phase shift, which deteriorates system stability under weak grid. In this article, a multi resonant component-based grid-voltage-weighted proposed, introduces series quasi-resonant components into path so that only background in are fed...

Abstract We present a hierarchical framework for approximately optimal control of redundant manipulators. The plant is augmented with low‐level feedback controller, designed to yield input‐output behavior that captures the task‐relevant aspects dynamics but has reduced dimensionality. This makes it possible reformulate problem in terms dynamics, and optimize high‐level controller without running into curse resulting hierarchy compares favorably existing methods robotics. Furthermore, we...

This letter investigates the magnetic integration of LCL filter in grid-connected inverters. By sharing an ungapped core and arranging windings properly, fundamental fluxes generated by two inductors cancel out mostly common core. Thus, with low flux level can be dramatically reduced. Although reluctance hardly zero, which implies inevitable coupling between integrated inductors, proposed scheme is still attractive if cross-section area material are made reasonable. Experimental results from...

Although high-frequency circulating current exists in parallel-operated inverters, it has not attracted as much attention low-frequency current, and thus been analyzed detail previously. In this paper, a mathematical model analysis are presented, which reveal the spectrum components their changing trends of currents caused by carrier phase differences. The impact difference on is also verified. A closed-loop control scheme proposed to suppress switching frequency difference. addition,...

This paper presents a technique for the reliability assessment of complex radial distribution systems considering restoration sequence and network constraints (NCs). In this technique, is represented using tree data structure to dynamically respond change topology induced by system reconfiguration. A parent-visit proposed determine affected area after failure occurs. breadth-first-search approach used divide load points into six classes based on times. An improved branch-oriented flow method...

In this paper, a wind turbine emulator (WTE) is designed and implemented considering different requirements from the development test of control strategy in doubly-fed power generating system. The WTE based on DSP system 4.2 kW separately-excited DC motor. can accurately reproduce characteristics real turbine. A PC interface also developed using C language LabWindows to provide friendly user real-time experiments. tested grid-connected variable speed constant frequency AC excited system,...

The injected grid current regulator and active damping of the LCL filter are essential to control LCL-type grid-connected inverters. Generally speaking, guarantees quality current, reduces resonance peak caused by makes it easier stabilize whole system. However, frequency responses interact with each other, making difficult design proper controller parameters investigate effect parameters. Taking proportional-integral (PI) compensator together capacitor-current-feedback active-damping as an...

Abstract Recently, catalytic valorization of biomass‐derived furans has received growing interest. 5‐Aminomethyl‐2‐furancarboxylic acid (AMFC), a furan amino acid, holds great promise in the aeras polymer and pharmaceutical, but its synthesis remains limited. In this work, we report chemobiocatalytic route toward AMFC by combining laccase‐TEMPO system recombinant Escherichia coli (named E. _TAF) harboring ω‐transaminase (TA), L‐alanine dehydrogenase (L‐AlaDH) formate (FDH), starting from...

Parallel operation of voltage source inverters is useful to achieve larger power capacity and improve the system reliability, which has become trend design. However, current harmonic parallel same as that every inverter when synchronized pulses are used for paralleled inverters. The interleaved helpful reduce distortion, though space left improvement limited, high-frequency circulating inevitably emerges. A novel scheme based on five-level vector modulation applied two three-level proposed...

Many reduced common mode voltage (CMV) modulation methods have been proposed for three-level inverters. However, most of them suffer from large current distortion because only part the available base vectors is utilized. The interleaved paralleling can reduce both CMV and output distortion, though reduction limited zero-sequence circulating (ZSCC) inevitably caused by phase-shifted carriers. To further while maintaining smaller ZSCC, a five-level (RCMV) method in this article, which treats...

Conventional reduced common-mode voltage discontinuous pulsewidth modulation method for a three-level inverter can reduce the and switching transitions compared with continuous modulation. However, it suffers from poor output current quality cannot provide additional performance enhancements when applied directly on parallel inverters. Based interactions between inverters, this article reveals that dual inverters could be analyzed controlled as single five-level inverter. idea, novel is...

TCGA-TCIA–Based CT Radiomics Study for Noninvasively Predicting Epstein-Barr Virus Status in Gastric CancerHuiping Zhao, MD1, Weiwei Li, MMed1, Peijie Lyu, Xiao Zhang, MMed2, Huan Liu, MD3, Pan Liang, MD1 and Jianbo Gao, MD1Audio Available | Share

For a current controlled grid-connected inverter, the grid voltage distortion will give rise to injected harmonics. Besides, for three-phase under unbalanced condition, currents become unbalanced. This paper aims at weakening effect of voltages on inverter with an LCL filter. The full-feedforward scheme is investigated in this paper. function stationary α-β frame filter proposed. consists three parts, which proportional part, derivative part and second part. With proposed voltages,...

An integrated zero common-mode voltage (ZCMV) modulation algorithm is developed in this article for dual-parallel neutral-point-clamped (NPC) inverters treated as an system. While the conventional methods achieve CMV elimination with cost of worse harmonic performance, proposed method guarantees a ZCMV and better current quality simultaneously by taking advantage extra space vectors provided paralleling. Specially designed switching sequences are to maintain balanced neutral point dc bus...

Abstract To ensure the safe and stable operation of 5G base stations, it is essential to accurately predict their power load. However, current short‐term prediction methods are rarely applied rationally in pertinent circumstances features station load over time. For high accuracy generalization capabilities, this work proposes a hybrid approach that combines gated recurrent unit (GRU) with particle swarm optimization (PSO) completes ensemble empirical mode decomposition adaptive noise...