Hybrid Simulation of ±500 kV HVDC Power Transmission Project Based on Advanced Digital Power System Simulator

In order to effectively imitate the dynamic operation characteristics of the HVDC （high voltage direct current） power transmission system at a real ±500kV HVDC transmission project, the electromechanical-electromagnetic transient hybrid simulation was carried out based on advanced digital power system simulator （ADPSS）. In the simulation analysis, the built hybrid model＇s dynamic response outputs under three different fault conditions are considered, and by comparing with the selected fault recording waveforms, the validities of the simulation waveforms are estimated qualitatively. It can be ascertained that the hybrid simulation model has the ability to describe the HVDC system＇s dynamic change trends well under some special fault conditions.

Energy-Efficient Large-Scale Antenna Systems with Hybrid Digital-Analog Beamforming Structure

A largescale antenna system （LSAS） with digital beamforming is expected to significantly increase energy efficiency （EE） and spectral efficiency （SE） in a wireless communication system. However, there are many challenging issues related to calibration, energy consumption, and cost in implementing a digital beamforming structure in an LSAS. In a practical LSAS deployment, hybrid digitalanalog beamforming structures with active antennas can be used. In this paper, we investigate the optimal antenna configuration in an N ＆#215; M beamforming structure, where N is the number of transceivers, M is the number of active antennas per transceiver, where analog beamforming is introduced for individual transceivers and digital beamforming is introduced across all N transceivers. We analyze the green point, which is the point of maximum EE on the EESE curve, and show that the logscale EE scales linearly with SE along a slope of lg2/N. We investigate the effect of M on EE for a given SE value in the case of fixed NM and independent N and M. In both cases, there is a unique optimal M that results in optimal EE. In the case of independent N and M, there is no optimal （N, M） combination for optimizing EE. The results of numerical simulations are provided, and these results support our analysis.

From Digital Analogs Through Recursive Machines to Quantum Computer

The report examines the evolution of computers from digital analogs through non-yon Neumann machines to quantum computers, which are also digital analogs. In the 60 years of digital analogs successfully developed at the Institute of Electromechanics of the USSR in Leningrad. An important stage in the development of non-classical multiprocessor machine performance and reliability has been the development of recursive machines, which was carried out at the Institute of Cybernetics led V.M.Glushkov and the Leningrad Institute of Aviation Instrumentation. The general approach to the synthesis is carried out through linguo- combinatorial modeling with structured uncertainty.

System Simulation Science and Simulation System Technology

This paper mainly discusses the following problems: the important meaning and special function of simulation system; the definition, contents and relationship of system and system simulation science; the definition and technology of simulation system and its equipments; and systematic description and exploration in relation to the developing trend of system simulation science and simulation system technology.

Low Complexity Hybrid Wideband Beamforming for Millimeter-Wave Massive MIMO-OFDM Systems

In mmWave massive multiple-input multiple-output(MIMO)communication systems,the extension of low-complexity narrowband precoding schemes to be operated on wideband systems under frequency-selective channels remains an important challenge at the current time.This paper investigates a low complexity wideband hybrid precoding scheme for mmWave massive MIMO multicarrier systems under a single-user,fully-connected hybrid architecture.We show that the radio frequency(RF)precoding/combining vectors can be directly derived from the eigenvectors of the optimal fully-digital covariance matrix over all subcarriers in order to maximize the sum rate of spectral efficiency.We also suggest a new method that iteratively reduces the residual error between the covariance matrix and the sum of products of precoding matrices over all the subcarriers to improve the performance in the case where the number of RF chains is higher than the number of streams.The results of the simulation show that the proposed schemes’complexity is low compared to the present methods,and their performance can almost reach the upper bound achieved by the optimal full-baseband design.

Digital/Analog Simulation Platform for Distributed Power Flow Controller Based on ADPSS and dSPACE

Distributed power flow controller,which is among the most powerful distributed flexible transmission equipments,is still only in the stage of the oretical research and digital simulation.In order to promote the engineering demonstration of a distributed power flow controller,it is urgent to establish a digital/analog simulation platform that supports closed-loop real-time simulation of a distributed power flow controller.In this paper,the electromagnetic transient model of a distributed power flow controller is established on ADPSS(advanced digital power system simulator).The rapid control prototype realized by dSPACE is connected to ADPSS to form a digital/analog simulation platform for a distributed power flow controller.Through a voltage control and power flow control simulation of the test system with a distributed power flow controller,the correctness and effectiveness of the constructed simulation platform are verified,which provides a new way for the verification of the new theory of a distributed power flow controller.

基于Simulink实现的数模混合控制系统仿真新方法

提出了一种采用Simulink实现数模混合控制系统的仿真方法。控制系统中实际的被控对象用连续Simulink模块构建的非线性连续系统来描述,同时采用Simulink模块与M函数相结合的形式,用信号上升沿触发子系统模拟闭环控制系统中的数字处理单元,即数字滤波与控制器部分,从而可真实地模拟周期性采集数据并处理数据的过程,最终实现数模混合控制系统的仿真。以连续搅拌反应釜基于卡尔曼滤波的状态反馈控制问题为实例,阐述了该仿真方法的具体实现过程。闭环仿真结果验证了该方法的有效性。

MATLAB/Simulink仿真技术在模拟与数字电路教学中的应用

介绍了MATLAB/Simulink的特点,结合模拟电路与数字电路的实例给出了教学实验系统的虚拟仿真设计。这种利用MATLAB/Simulink对实验进行模拟仿真的教学方法比通常的教学方法更加形象和生动,教学效果明显提高,有助于培养学生的创新意识和设计能力。

用于实时仿真的一类Hybrid方法

本文提出一类可用于实时数字仿真的Ｈｙｂｉｒｄ方法，对这类方法的基本理论作了分析，在Ｋ＝２时给出了具体的几组算法公式，数值试验结果表明这类实时算法是有效的、可行的。

Digital and analog hybrid control in adaptive interference cancellation system

The digital proportion control is introduced to improve the performance of the analog adaptive interference cancellation system （ICS）. For the high frequency parts of the signals after multiplier are not required,the sampling frequency need not satisfy the sampling theorem for high frequency. Because the sampling,calculation and output expend time in digital control,the ideal condition,delay condition and delay-wait condition are taken into account. Through analyzing the system model with three conditions,we gain the stable conditions of the system,the optimization step factors that can make the system converge fastest and the formulas of the interference cancellation ratios （ICRs）. One step convergence can be accomplished under ideal condition,whereas the system can not converge in one step under delay condition and delay-wait condition. The calculation results show the convergence speed of delay-wait condition is slower than that of delay condition. The ICR is improved with the increase of the step factor which is in stable bound,but the convergence speed is decreased if the step factor exceeds the optimization step factor. In order to avoid that confine,the method of amending the steady state weight to improve the ICR is proposed. The analyses are in agreement with the computer simulations.

MATLAB/Simulink仿真在模数转换器教学中的应用

针对模数转换器(ADC)教学中,学生仅依赖理论学习,很难和实际ADC结构及应用联系起来等问题,以目前应用较为广泛的流水线型ADC为例,探讨MATLAB/Simulink仿真在ADC教学中的应用。通过在Simulink环境下搭建流水线ADC的行为模型,并进行仿真结果演示,使学生对此类ADC的结构和工作原理有了直观的认识,提高了课程的教学效果。

Design and Application of Software for Generating Simulated Signal Data

Simulated signal, produced by digital to analog converter, is important and necessary in many fields, such as electronic experiment, equipment debugging and maintenance, especially, in medical area. In this paper, the design and application of an effective software which may be used to generate simulated signal data by special wave picture obtained by scanner or drawing software are presented. First, we introduce how to realize producing needed data that meet the given conditions including amplitude, samples and resolution by this software. Second, the method and steps of getting the stimulated signal data from wave figure file is given. Third, an example of application about this software to generate simulated physiological signal data is shown. Then, the data are put into use and by digital to analog converter, an idea stimulated signal is produced. Therefore, with full confidence, we could draw a conclusion that it is very convenient and effective to get needed data for digital to analog conversion to generate all kinds simulated signal with a novel method.

风电机组运行动态数字孪生建模及半物理仿真

面向数字孪生技术所提出的精准映射与实时仿真需求,针对大型风电机组复杂非线性运行特性,提出了一种多输入-多输出(multi-input multi-output,MIMO)有限差分域-混合半机理(finite difference domain-hybrid semi-mechanical,FDD-HSM)数字孪生建模方法,建立了含物理控制器的风电机组数字孪生半物理仿真系统。推导机组集成动态MIMO-FDD-HSM模型结构;定义可表征机组运行工况的有限差分回归向量,完成全工况下有限差分空间紧致凸划分、参数模型辨识以及非参数模型训练;联合物理控制器搭建风电机组数字孪生仿真系统,开展硬件在环实时仿真。结果表明:该仿真系统具有高精度、实时逼近能力。

数字专网的通信终端与加密组件测试系统设计

为提高数字专网的通信终端与配套加密组件测试效率,降低实装测试环境的构建、运维及人力成本,开展了基于半实物仿真的测试系统设计;对通信终端与加密组件的测试需求进行了分析,提出并实现了一种模拟数字专网的通信建链流程和加密通信业务流程的方法;采用了通用AXIe(仪器与测试高级电信计算架构的扩展)测试平台与扩展测试仪器的架构进行系统设计,实现与不同测试对象的物理接口适配、信号调理以及报文数据交互控制,为通信终端及加密组件的加密业务成功率测试、语音质量评测以及远供工作电流测量提供自动化测试技术手段;经验证,测试系统通信链路时延<100 ns,可为通信终端提供良好的语音质量评测环境,PESQ(感知语音质量评测模型)测试≥4.20,可支持加密业务成功率指标≥99.9%的无人值守测试。

数模混合二维相控阵雷达远场收发校准方法研究

本文提出了一种基于最小系统设计准则的数模混合二维相控阵雷达远场收发校准方法,给出了实现流程、数据分析过程和实测结果。方向图的实测结果显示本文提出的校准方法得到的收发方向图主要技术指标良好且均满足使用要求,在实际工程中具有较好的操作性和推广性。

自适应聚类的图像块分级DCT混合数模无线传输方法

提出了一种新颖的混合数模无线传输方法来实现高质量的图像传输。首先,从原始图像中减去先下采样后上采样的图像来得到残差层图像。其次,提出了一种自适应聚类的块分级离散余弦变换算法来有效去除残差层图像像素之间的相关性。最后,提出了一种基于图像块等级的不等功率分配策略来进一步提升接收端的图像质量。大量的实验结果表明,所提方法在定性评估和定量度量两方面都明显优于现有较成功的混合数模图像无线传输方法。

白鹤滩-江苏特高压混合级联直流工程数模仿真平台构建及特性研究

白(鹤滩)—江(苏)特高压直流输电工程是世界上第1个受端采用电网换相换流器(line-commutated converters,LCC)+模块化多电平换流器(modular multilevel converters,MMC)级联结构的实际工程,且受端分层接入4个交流馈入点。根据白江工程设计资料与实际参数,构建了包含与实际工程功能一致的MMC数字阀控系统、小步长现场可编程门阵列(field programmable gate array,FPGA)阀体仿真模型、直流实际控制保护装置的白江工程数模混合实时仿真平台,实现对白江工程百纳秒–微秒–毫秒级多时间尺度精准仿真。通过大量的功能性试验,以及与实际工程录波的一致性对比试验,验证了仿真平台的准确性;仿真分析了白江工程特殊结构和控制模式能在一定程度上提升对受端交流故障的抵御能力,可避免换相失败或降低换相失败的功率扰动,并改善受端故障引起送端交流过电压问题。本平台将继续应用于多回直流馈入华东的大电网数模混合仿真研究中。

一种星载数模混合阵列结构及波束形成算法

6G星地融合网络对卫星通信系统提出了高速率低时延低能耗的要求,由于星地链路信道环境复杂多变且容易受到干扰,需要研究干扰场景下的低成本可实现阵列架构及算法。针对这一问题,设计了一种数模混合阵列结构,子阵采用50%稀疏馈电以及最小二乘波束形成算法,超阵采用最小二乘与线性约束最小方差波束形成算法,并理论分析了阵列结构的可行性,证明子阵的零点能够抑制超阵的栅瓣。仿真结果表明,该结构以更低的复杂度实现了大规模阵列的效果,波束方向图指向明确且零陷深度足够,对干扰的抑制明显,获得了接近理想阵列增益的BER性能。

基于稀疏贝叶斯学习的混合mMIMO系统波达方向估计

波达方向估计是混合mMIMO系统波束成形得以应用的前提,基于协方差矩阵重构的子空间方法在相干信号和有限快拍数条件下性能损失较大。为了应对上述挑战,提出了一种基于稀疏贝叶斯学习的混合mMIMO系统波达方向估计方法,主要创新之处在于:将混合mMIMO系统的波达方向估计问题转化为稀疏信号恢复问题,从而绕过空间协方差矩阵重构,避免了其带来的性能损失。为了便于进行贝叶斯推断,进一步利用变分贝叶斯近似思想,在恢复稀疏信号的同时,自适应估计出未知参数,显著改善了对噪声和相干信号的鲁棒性,提升了有限快拍数情况下的波达方向估计性能。数值模拟结果验证了所提方法的优越性。

基于数字孪生仿真的半导体可重入混合流水车间联合调度优化研究

在新一代信息技术与高端制造产业加速融合渗透的背景下,文中针对半导体车间订单动态到达、车间生产信息透明度低的问题,提出了一种基于数字孪生仿真的半导体可重入混合流水车间联合调度方法。首先,设计了一种基于AnyLogic的数字孪生仿真架构,并在此基础上构建了高保真数字孪生仿真模型,对多源异构数据虚实交互、多维多尺度孪生模型运行机理进行了深入探讨;其次,综合考虑最大完工时间、碳排放量和AGV利用率建立联合调度模型,提出了一种结合数字孪生的ENSGA-Ⅱ算法进行求解,并将其嵌入AnyLogic孪生模型实现实时调度;最后,基于差异化场景和半导体车间任务实例,验证了所提方法的有效性。