In this article, a novel Γ-source circuit breaker (CB) that can offer automatic fault isolation with no reflected current in the feeding source is proposed for protection of dc microgrids. Compared conventional Z-source CBs, topology utilizes fewer elements through magnetic coupling, thus allowing considerably reduced volume and weight. To accurately quantify elements, detailed modeling over both short-circuit overload faults carried out. The derived equations are significantly valuable...

This paper introduces a novel five-level nested neutral point piloted (NNPP) converter and analyzes the operating principle of NNPP converter. presents space vector pulse width modulation (SVPWM) algorithm based on gh coordinate for First, common-mode voltage is reduced by choosing appropriate redundant switching states. After that, floating-capacitor balance control strategy presented. The switch combinations each phase are determined requirements voltages respectively hardware mapping...

The five-level nested neutral-point-pilot (NPP) topology, as a new structure for converters, bears the advantages of high power density, robustness, and flexibility is therefore suitable high-voltage high-power applications. For multilevel converter, number electronic switches increases, risk switch failure together with complexity fault detection tolerance control. requirements higher operational stability reliability continue to grow. However, studies on converters are limited. In this...

DC microgrids that feature a simple and efficient integration with renewable energy sources storage elements have drawn increasing attention in industrial applications. In this article, bidirectional Z-source circuit breaker an O-shaped impedance network (abbreviated as O-Z-source breaker) is proposed to guarantee the reliable operation of dc microgrids. By simplified structure, allows power flow fewer components compared conventional breakers. Increased operating efficiency can also be...

Metro systems are one of the most important transportation in people’s lives. Due to huge amount energy it consumes every day, highly-efficient operation a metro system will lead significant savings. In this paper, new integrated Energy-efficient Operation Methodology (EOM) for is proposed and validated. Compared with other saving methods, EOM does not incur additional cost. addition, provides solutions frequent disturbance problems systems. can be divided into two parts: Timetable...

This paper presents the active capacitor voltage-balancing (ACVB) methods based on dynamic model for a five-level nested neutral-point piloted (NNPP) converter using hybrid carrier modulation. The traditional modulation provides natural voltage balancing of floating capacitors and dc-link capacitors. First, ability under steady-state ideal conditions is theoretically proved. However, there are accumulated errors deviations voltages in practical applications, especially conditions. In order...

A novel fuzzy multiobjective model is proposed for service restoration of shipboard power systems. In this model, the objective functions different dimensions are normalized to interval <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$[0, 1]$</tex></formula> , and these integrated by using analytic hierarchy process. Meanwhile, priorities load switch taken into account. The heuristic rule replacing...

Modular multilevel cascade converter (MMCC) is a family of the emerging converters that are configured with cascaded connection full-bridge submodules or half-bridge ones by distinct topological structures. So far, MMCC can be classified basic configurations and submodule types into single-star full-bridge, double-star (modular (MMC)), back-to-back (indirect MMC), triple-star matrix converter, M3C), single-delta double-delta (Hexverter). This study introduces generalised standard analytical...

DC microgrids have attracted increasing concern in industrial applications due to a simple and efficient integration with renewable energy sources, battery storage, variable speed generators motors. However, extensive application of dc architecture is still restricted by fault protection challenges posed the absence natural current zero-crossing. This paper has proposed novel thyristor-based circuit breaker one-shot triggering commutating circuit, which maintains compact size as no...

Moving average filter (MAF)-based phase-locked loops (PLLs) have received considerable attention in recent years due to their attractive features. Indeed, they are able completely eliminate the unwanted effect of harmonics, dc offset, and unbalanced voltages. Unfortunately, these advantages come at cost open-loop bandwidth reduction, which worsens system's dynamic response. The main challenge is estimate phase frequency timely precisely from an imbalanced distorted voltage. In addition,...

Modular multilevel converter (MMC) is a newly introduced topology of converter, which based on cascade connection chopper-cells per leg. This paper presents novel MMC, in which, traditional H-bridge (HB) cells are used for more levels output voltage. Corresponding control strategy presented and explained details, including phase-disposition (PD) sinusoidal pulse width modulation (SPWM) strategy, methods chopper-cells, several controls capacitor voltage balancing. Output twice as many those...

The open-circuit faults of power semiconductor devices in multilevel converters are generally diagnosed by analyzing circuit signals. For with five or more levels, the difficulty fault detection increases increasing topological complexity, number switching and candidate signal parameters. In this paper, a complete solution for five-level nested neutral-point piloted (NNPP) converter is proposed based on improved unsupervised feature learning algorithms. Feature engineering machine algorithms...

Automatic coal-rock recognition (ACRR) is of considerable theoretical and practical significance for unmanned coal mining. To the best our knowledge, this first study to assess laser-induced breakdown spectroscopy (LIBS) combined with an artificial neural network (ANN) automatic recognition. Each sample in was subjected LIBS testing spectrum collection 20 times air, average value taken as data. Spectral data were optimized dimensionality reduction performed using partial least-squares...

In this paper, a scheme of FPAG-based three-level space vector modulation (SVM) inverter is proposed in details. Compared to the traditional two-level inverter, using SVM control has superior performance though bringing about much computational complexity. Therefore, FPGA-based implementation could solve problem well. The algorithm for described, including approach calculate dwell times each switching state volt-second characteristic, determining location and principle selecting sequences...

Modular multilevel converter (MMC) is a newly introduced topology of with six arms, each which formed by series connection several chopper-cells and an inductor. This paper first analyzes the working principle high-voltage large-capacity MMC. Then, novel control strategy its system solution are proposed explained in details, including staircase modulation methods on chopper-cells, two controls capacitor voltage, average balancing arm-balancing. Based PSIM, simulation platform 100-level...

Electromagnetic interference is a significant problem in high-speed circuits. To minimize its effect and improve the electrical characteristics of circuits such as signal integrity electromagnetic compatibility, application an isolation structure with bandgap (EBG) considered. In this paper, novel wideband EBG proposed for EMI reduction multilayer printed circuit boards (PCB), which kind improved L-bridge used additional series inductance, equivalent inductance can be increased...

Modular multilevel converter-battery energy storage system (MMC-BESS) has a good engineering application. When MMC-BESS is connected to the grid, real-time phase angle of grid an important parameter. simulation model based on virtual synchronous generator (VSG) built in MATLAB. The results show control algorithm VSG can improve dynamic response and stably detect grid.

The topology of energy storage inverter is adopted with T-type three-level structure. characteristics are analysed when the working on grid-connected and isolated-island operation. In order to satisfy stable switching operation from isolated-island, a seamless control strategy based virtual synchronous generator proposed. A simulation model for converter built in MATLAB verify correctness proposed strategy.

Poor line power factor is one of disadvantages the cascade speed control in wound rotor induction motor drives. So a new method to improve system proposed, which integrates correction (PFC) and control. Then principle (CSC) with PFC analyzed detail. For low slip voltage frequency, novel three-phase realized symmetrical balanced Scott transformer single phase active PFC. Specific considerations calculations parameters used CSC are discussed. Simulation model established MATLAB/SIMULINK....

In this paper, a novel design approach of the PI controller used for individual DC voltage balancing control cascaded H-bridge converter-based STATic synchronous COMpensator(STATCOM) is presented. By means phase shift sinusoidal pulse width modulation, using two loops(DC loop and angle loop) to ensure balance, proposed can calculate parameters loops relative accurately by finding relationship input output controller, The simulation results verify that method has good effects voltage,...

The dual-PWM adjustable speed drives (ASDs) inject interharmonics into the distribution grid, causing low-frequency oscillation (LFO) in grid. This article investigates common-modulation process of motor load torque and how it resulting interharmonic components front end back-to-back PWM-based ASDs. Particular emphasis is given to theoretical analysis interharmonic-causing frequency aliasing fundamental root-mean-square (rms) LFO. Besides, based on Bessel PWM switching function principle, a...