Effect of temperature on heavy ion-induced single event transient on 16-nm FinFET inverter chains

The variations of single event transient(SET)pulse width of high-LET heavy ion irradiation in 16-nm-thick bulk silicon fin field-effect transistor(Fin FET)inverter chains with different driven strengths are measured at different temperatures.Three-dimensional(3D)technology computer-aided design simulations are carried out to study the SET pulse width and saturation current varying with temperature.Experimental and simulation results indicate that the increase in temperature will enhance the parasitic bipolar effect of bulk Fin FET technology,resulting in the increase of SET pulse width.On the other hand,the increase of inverter driven strength will change the layout topology,which has a complex influence on the SET temperature effects of Fin FET inverter chains.The experimental and simulation results show that the device with the strongest driven strength has the least dependence on temperature.

Symmetrical dynamical characteristic of peak and valley current-mode controlled single-phase H-bridge inverter

Complex dynamical phenomenon was studied in the single phase H-bridge inverter which was controlled by either a peak current or a valley current. The state functions and the discrete iterative map equations were established to analyze the dynamical phenomenon in the single phase H-bridge inverter. The dynamical characteristics of the single phase H- bridge inverter, such as time domain waveform diagram, bifurcation diagram, and folding map, were obtained by using the numerical calculation when the circuit parameters varied in specific range. Moreover, the simulation results were obtained by using the OrCAD-PSpice software to validate the numerical calculation. Both the numerical calculation and the circuit simulation show that the symmetrical dynamical phenomenon occurs in the single phase H-bridge inverter controlled by the peak current or the valley current.

Improved Interleaved Single-Ended Primary Inductor-Converter forSingle-Phase Grid-Connected System

The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial uses.The power generated from the PV system is erratic and hence there is a need for an efficient converter to perform the extraction of maximum power.An improved interleaved Single-ended Primary Inductor-Converter(SEPIC)converter is employed in proposed work to extricate most of power from renewable source.This proposed converter minimizes ripples,reduces electromagnetic interference due tofilter elements and the contin-uous input current improves the power output of PV panel.A Crow Search Algo-rithm(CSA)based Proportional Integral(PI)controller is utilized for controlling the converter switches effectively by optimizing the parameters of PI controller.The optimized PI controller reduces ripples present in Direct Current(DC)vol-tage,maintains constant voltage at proposed converter output and reduces over-shoots with minimum settling and rise time.This voltage is given to single phase grid via 1�Voltage Source Inverter(VSI).The command pulses of 1�VSI are produced by simple PI controller.The response of the proposed converter is thus improved with less input current.After implementing CSA based PI the efficiency of proposed converter obtained is 96%and the Total Harmonic Distor-tion(THD)is found to be 2:4%.The dynamics and closed loop operation is designed and modeled using MATLAB Simulink tool and its behavior is performed.

Randomized Integral Gain of Pi Current Controller for A Single Pv Inverter System

This paper is concerned with the problem of network power quality when grid connected systems are used to feed the grid. These systems use power electronic components such as inverters that produce harmonics which adversely affect the power quality of the distribution network. Instead of using a conventional PI current controller with a fixed proportional and integral gain, development of new control method is considered to overcome the total harmonic emissions in PV inverters. It considers a modification to the controller where a random integral gain is used in the system. Experimental hardware is developed and result shows a reduced total harmonic distortion (THD) of the output current when tested with a resistive load.

A High-Efficiency Single-Stage Low-Power Photovoltaic Inverter System with Maximum Power Point Tracking Control

This paper proposes a single-stage inverter system with maximum power point tracking control (MPPT) applicable in low-power photovoltaic (PV) energy conversion systems. The proposed system is successfully implemented using a single digital signal processor (DSP) TMS320F2808. The proposed single-stage inverter system has the following features: 1) the ability to harvest the maximum PV power using two simple and effective current sampling methods;2) flexible topology based on the positioning of DC link capacitor on the outside of the inverter bridge circuits;3) reduced volume and higher efficiency than the conventional two-stage inverters, and 4) MPPT accuracy of 99.3% with overall efficiency of 90% under the full-load condition.

Control and Implementation of Single-Inverter Microgrid

In this paper, simulation and implementation way for practical control of Single Inverter Microgrid (SIMG) is presented. This system is equipped by solar system, wind energy conversion system (WECS), and microturbine system. Each DG’s has controlled independently. This is a kind of decentralize control because each DG’s has difference controller. Control of Microgrid (MG) during both grid tie and islanding modes is presented. Solar system and WECS are modeled based on santerno products. This system is compared with three inverter MGs with Centralize control strategy. Controlled signals show that SIMG is more reliable and economical. THD is improved and strategy is simplified for SIMG.

A Cascade Multilevel Inverter Using a Single DC Source

3.SWITCHING ANGLES If the nominal capacitor voltage is chosen as Vdc/2, then one can compute the switching anglesθ1,θ2,andθ3.Following the development,the Fourier series expan- sion of the(staircase)output voltage waveform of the multilevel inverter as shown in Fig.2(a)

The Research of Three-phase Boost/Buck-boost DC-AC Inverter

This paper presents a new inverter based on three-phase Boost/Buck-boost single-stage inverter. The basic configuration of the new topology and their fundamental principle are firstly introduced, the method of design double-loop controller and sliding mode controller are clarified, analyzed and compared in the following. Finally the validity and feasibility of the new topology are tested by simulation. The results indicate that regulation of the voltage transfer ratio and output frequency can be realized optionally by the new converter, furthermore the harmonic distortion of waveform is low. So the inherent drawback of low voltage transfer ratio of traditional converter is effectively settled. This study may provide inspiration for further engineering application.

Minimization of Switching Devices and Driver Circuits in Multilevel Inverter

The various configurations of multilevel inverter involve the use of more numbers of switching devices, energy storage devices and/or unidirectional devices. Each switching unit necessitates the add-on driver circuit for proper functionality. Cascaded H-Bridge Multilevel Inverter requires overlapped switching pulses for the switching devices in positive and negative arms of the bridge which may lead to short circuit during the device failure. This work addresses the problems in different configurations of multilevel inverter by using reduced number of switching and energy storage devices and driver circuits. In the present approach Single Switch is used for each stair case positive output and single H-Bridge for phase reversal. Driver circuits are reduced by using the property of body diode of the MOSFET. Switching pulses are generated by Arduino Development Board. The circuit is simulated using Matlab. More so, through experimental means, it is physically tested and results are analyzed for the 5-step inverter and thereby simulation is fully validated. Consequently, cycloconverter operation of the circuit is simulated using Matlab. Moreover, half bridge configuration of the multilevel inverter is also analyzed for high frequency induction heating applications.

Neural Network Based on SET Inverter Structures: Neuro-Inspired Memory

This paper presents a basic block for building large-scale single-electron neural networks. This macro block is completely composed of SET inverter circuits. We present and discuss the basic parts of this device. The full design and simulation results were done using MATLAB and SIMON, which are a single-electron tunnel device and circuit simulator based on a Monte Carlo method. Special measures had to be taken in order to simulate this circuit correctly in SIMON and compare results with those of SPICE simulation done before. Moreover, we study part of the network as a memory cell with the idea of combining the extremely low-power properties of the SET and the compact design.

逆变型电源场站故障稳态电流实用化计算方法

单机倍乘法常用于逆变型电源场站的故障稳态建模,可简单估算场站短路电流水平,但计算精度有待提升。文中首先分析了低电压穿越控制策略约束下,有功出力、电压跌落程度对发电单元输出的稳态电流的决定性作用,得出故障稳态电流输出特性曲线,基于此分析了场站电气距离及有功出力差异对单机倍乘法计算误差的影响。在误差分析的基础上,提出了计及发电单元分布特性的改进单机倍乘法。该方法在发电单元接入点电压计算中,利用等值阻抗来等效发电单元与并网点的电气距离;将场站分群等值为两台机组,减小发电单元间有功出力差异对短路特性的影响。不同场景下的仿真分析表明,改进方法计算精度较单机倍乘法有着较大的提升。所提方法仅需通过简单计算即可实现场站分群和短路电流聚合,有较好的工程实用性。

有源缓冲型逆变器功率解耦技术研究

为实现单级单相升压逆变并能有效抑制直流侧二次纹波电流,提出一种带有源缓冲的电流型逆变器电路拓扑,研究该逆变器的6种电路模态并提出其两模态调制策略和三模态调制策略,设计2种调制策略下的模型预测控制策略,提供主电路参数设计准则。从储能电感电流的最大脉动量与二次纹波含量两方面对2种调制策略进行对比分析,得出了三模态调制策略具有更好纹波抑制效果的结论。对2种调制策略下的逆变器进行仿真分析,仿真结果表明,三模态调制下电路的输出电压总谐波失真率、电感电流相对脉动量与二倍频含量均低于两模态调制下的数据。设计并搭建500VA 48VDC/220V50HzAC有源缓冲型单级单相升压逆变器实验装置,给出了三模态调制下基于模型预测控制的逆变器实验波形,进一步证实了所提研究方案在实现单级升压逆变的同时具有二次纹波抑制能力。

一种单电源九开关二倍升压九电平逆变器

针对现有九电平逆变器存在使用器件较多且调制策略复杂的问题,提出1种新型的开关电容九电平逆变器,其拓扑仅需1个直流电源、9个开关、2个电容和2个二极管即可输出九电平,同时实现二倍升压。该逆变器具有电容电压自平衡的能力,无需复杂的控制算法和外部均压电路来维持电容电压平衡。采用多载波层叠调制策略对该逆变器进行调制,逆变器中4对开关的工作状态互补,可以使用非门逻辑电路来降低调制策略的复杂度。首先对该逆变器的拓扑结构和工作原理进行理论分析;其次,对调制策略进行了详细介绍,并将所提拓扑与其他九电平拓扑进行比较,介绍了该拓扑的优点;最后,搭建的仿真电路和实验平台验证了所提拓扑及调制策略的可行性和有效性。

基于盲源分离和机器学习的光伏并网逆变器故障诊断

针对光伏并网逆变器单个开关管发生开路故障不易察觉的问题,提出了一种基于盲源分离和机器学习的诊断方法。首先,采用FastICA算法实现单个开关管开路故障的判定;其次,提取旋转电流在时域和频域下的特征值;最后,以旋转电流特征值为输入、逆变器工作状态编码为输出进行机器学习模型训练,并对模型进行交叉验证。仿真实验结果表明,该方法的开路故障诊断准确率较高。

Analysis and simulation of a single-phase seven-level inverter controlled by modified sinusoidal PWM technique

In this paper,a modified sinusoidal pulse width modulation(MSPWM)technique and a modified single-phase H-bridge seven-level inverter is proposed.The switching pulses for the proposed seven-level inverter are generated using a single triangular carrier waveform,a fully rectified sinusoidal signal,and three stepped reference signals(Uref1,Uref2 and Uref3).Using optimization technique,the magnitude of the stepped reference signal is determined so that the total harmonic distortion(THD)of the output voltage waveform is minimum and the fundamental component,RMS value of the voltage is improved for a given modulation index Ma as compared to the sinusoidal pulse width modulation(SPWM).By the implementation of the new scheme,the seven-level of the inverter output voltage level(+Vdc,+2Vdc/3,+Vdc/3,0,−Vdc,−2Vdc/3,−Vdc)is obtained for any given modulation index.Similarly,if only two stepped reference signals are used then the inverter will act as a five-level inverter for any modulating index Ma.The proposed MSPWM and seven-level inverter are simulated on MATLAB/SIMULINK for R,R-L load and on a single-phase capacitor-start and capacitor-start-run Induction Motor.

单电压环构网型并网逆变器暂态稳定性分析

随着电力电子化电力系统的快速发展,构网型并网逆变器作为新型电源得到了广泛关注,其中单电压环构网型并网逆变器因具有更强的小信号稳定性而在新能源并网中具有独特优势。同时,构网型并网逆变器在大扰动下呈现与同步电机不同的暂态响应,容易产生暂态失稳。针对这一问题,以单电压环构网型并网逆变器大扰动模型为基础,采用相平面图的方法分析了大扰动下功率控制环、电压控制环对逆变器的暂态作用,给出了关键控制器参数对暂态稳定性的影响,刻画了功角的暂态响应特性。同时,揭示了有功控制环、无功控制环和单电压环在暂态期间会改变功角超调量、逆变器输出电压幅值和变化率,进而影响并网逆变器的暂态稳定性。基于上述分析,给出了减小有功和无功下垂系数,增大电压积分系数和低通滤波器截止角频率的控制参数优化方法,可增强单电压环构网型并网逆变器暂态稳定性。最后,通过Matlab/Simulink仿真验证了分析的准确性与可行性。

基于改进型QPR的并网逆变器复合控制策略

针对准比例谐振(QPR)控制对高次谐波和直流抑制能力差等问题,提出了一种改进型QPR控制与直流前馈补偿的复合控制策略。该策略在QPR控制的基础上加入了高次谐波补偿,并在控制基波电流的电流外环上加入含积分控制器的直流分量补偿环节。在对并网电流所含3、5、7次谐波进行抑制的同时,降低了并网电流中所含直流分量。仿真结果表明,与QPR控制相比,所提控制策略直流含量从0.05降为0.01,总谐波畸变率下降了1.48%,具有较好的抑制效果。

计及锁相环动态的单相并网逆变器建模及稳定性研究综述

随着可再生能源渗透率的提高,电网呈现出高电网阻抗的弱电网甚至极弱电网特征,锁相环与电网阻抗交互作用将恶化跟网型逆变器低频稳定性。近年来,诸多文献针对单相跟网型逆变器中的低频振荡问题进行了研究,但缺乏对现有成果系统性地梳理和总结,难以明确进一步的研究重点。为此,该文首先梳理和评述现有计及锁相环影响的逆变器建模及稳定性分析方法,直观地阐述锁相环引起的负阻效应对系统低频稳定性的影响机制,并在此基础上,从改进电流控制环和锁相环角度,系统性地归纳和分析现有各种低频鲁棒性提高方法。最后,总结现有研究在稳定性分析及鲁棒性改进上的不足及研究关键点和难点,指出进一步的研究方向。

基于谐波注入分段供电永磁直线同步电机变流器开路推力波动抑制

该文提出一种电流谐波注入的方法,减小长定子分段并联供电永磁直线同步电机系统的驱动变流器发生单相开路故障下电机推力波动。首先,根据动子在定子段的位置,推导出分段单元电机的电压方程,得到各个单元电机的推力表达式和系统总推力。然后,依据变流器单相开路前后的全耦合状态下单元电机基波磁动势不变的原则,构造降阶坐标变换矩阵,得到电机的电压方程和推力表达式。采用注入谐波电流、优化故障后直线电机的输出推力的方式,消除变流器单相开路故障产生的4次和6次推力谐波并消除耦合因数变化对电机推力影响;通过多变流器协同控制多单元电机,有效降低变流器单相开路故障后的推力波动,提高电机的最大输出推力。仿真和实验验证该方法的有效性。

单级旋转倒立摆系统辨识与随动稳定控制方法研究

针对单级旋转倒立摆系统参数辨识和随动稳定控制问题,首先建立倒立摆在不受外力控制,摆杆自然下垂的顺摆模型,基于顺摆模型采用快速傅里叶变换方法对系统参数进行辨识;然后推导顺摆模型与倒摆模型之间的关系,进一步得到倒立摆的倒摆模型;根据辨识出的倒摆模型,采用线性二次型控制器对其进行稳定控制,并进行了数值仿真与实物实验验证。研究结果表明,通过辨识得到的系统模型更加精确,对比直接测量参数得到的系统模型,控制效果更好,且能对随动输入指令进行更优的跟随。该方法可以有效避免量测误差,提高模型的准确性,为火炮随动稳定控制提供参考。