多端交直流系统状态估计

综合分析了近些年来关于多端交直流系统（ＡＣ／ＭＴＤＣ）状态估计的算法,并提出了一种ＡＣ／ＭＴＤＣ状态估计分析的算法－改进交替求解法,此方法由于在对交流系统和直流系统进行解耦时未忽略耦合量,所以可以保证算法的收敛性。同时,由于对交直流系统实现了解耦,此算法可以采用简便的交直流系统交替迭代形式,并能很方便地与现有的交流状态估计算法相结合,且实现简单,算例验证了所提出的方法是正确的,有效的。     

MATLAB在电力系统分析中的应用

本文在简单地介绍了ＭＡＴＬＡＢ语文和潮流计算的基本知识后,着重阐述了ＭＡＴＬＡＢ语言在电力系统潮流计算中的应用,通过分析ＤＡＰＡ算法的程序结构总结出了ＭＡＴＬＡＢ语言在处理矩阵运算方面的无可比拟的优越性。     

用铁磷提高锶铁氧体性能的研究

本文探讨了以铁磷、碳酸锶作原料，采用ＣａＣＯ３，Ａｌ２Ｏ３，ＳｉＯ２等作添加剂，通过控制摩尔比、预烧料晶体粒大小和形状以及相关工艺条件，获得高性能的各向异性锶铁氧体的方法。所制备的磁体性能可达：Ｂｒ：０．３７９－０．４１０Ｔ；ＨＣＢ：２１４－２６９ｋＡ／Ｍ；ＨＣＪ２２３－３０４ｋＡ．／ｍ；（ＢＨ）ｍａｘ：２７２－３２．２ｋＪ／Ｍ＾３。     

单片机MCS—48用于A／D转换的方法

本文介绍了利用单片机ＭＣＳ－４８和８位Ｄ／Ａ芯片实现Ａ／Ｄ转换的方法，该方法在Ａ／Ｄ转换时间允许的情况下，实现了成本较高的Ａ／Ｄ转换器的功能。文中重点介绍了实用电路和工作原理。     

极谐振软开关过渡三相PWM逆变器研究新进展

软开关技术在ＤＣ／ＤＣ变换,单相ＤＣ／ＡＣ变换方面得到了很大的发展并获得了大量的实际应用,在三相ＤＣ／ＡＣ逆变器方面,研究人员也作了大量的工作,提出了许多的电路拓扑。本文尝试对几种最有可能实际应用于三相电机驱动的软开关逆变器电路（ＡＲＣＰＩＺＶＴ－ＰＷＭ ＺＣＴ－ＰＷＭ）进行了分析和描述,给出了典型电路及有关的波形,并分析其优缺点。     

单片机MCS－48用于A／D转换的方法

本文介绍了利用单片机ＭＣＳ－４８和８位０／Ａ芯片实现Ａ／Ｄ转换的方法，该方法在Ａ／Ｄ转换时间允许的情况下，实现了成本较高的Ａ／Ｄ转换器的功能。文中重点介绍了实用电路和工作原理。     

厦门电力调度自动化iES—500主站系统及其数据库

ｉＥＳ－５００系统是一个以电网监控和数据采集系统／能量管理系统／配电管理系统（ＳＣＡＤＡ／ＥＭＳ／ＤＭＳ）为中心的开放式应用环境,以全新的计算机软硬件技术为基础符合电力调度自动化新的发展要求。厦门ｉＥＳ－５００系统同时具备ＳＣＡＤＡ和ＥＭＳ功能。本文将对ｉＥＳ－５００系统的结构进行分析,并着重论述其数据库系统。     

保留非线性的电力系统概率潮流计算

提出了一种新的概率潮流计算方法,它保留了潮流方程的非线性,又利用了Ｐ－Ｑ解耦方法,因而数学模型精度较高,且保留了Ｐ－Ｑ解耦的优点,有利于大电网的随机潮流计算,用提出的方法对一个典型的系统进行了计算,其数值用ＭｏｎｔｅＣａｒｌｏ随机模拟作了验证,得到了满意的结果。     

保留非线性的电力系统概率潮流计算

提出了一种新的概率潮流计算方法。它保留了潮流方程的非线性,又利用了Ｐ－Ｑ解耦方法,因而数学模型精度较高,且保留了Ｐ－Ｑ解耦的优点,有利于大电网的随机潮流计算。用提出的方法对一个典型的系统进行了计算,其数值用 Ｍｏｎｔｅ Ｃａｒｌｏ随机模拟作了验证,得到了满意的结果。     

AC／DC（开关型）电源变换器APFC技术的研究

分析了有源功率因数校正（ＡＰＦＣ）技术,并结合 ＭＬ４８２１专用 ＩＣ设计了低谐波、高功率因数的ＡＰＦＣ－ＡＣ／ＤＣ（开关型）电源变换器的应用电路。     

含多类型直流的交直流混联电网潮流计算方法适用性分析

作为电网发展的新阶段,交直流混联电网呈现多类型直流参与、大规模交直流互联的特点,而关于统一迭代和交替迭代2种潮流计算方法的适用性尚未得到深入分析。为此基于含多类型直流的交直流混联电网对2种潮流计算方法的运算性能进行对比研究。推导了含常规直流、柔性直流、混合直流的交直流混联电网潮流模型,进而提出了相应的统一迭代法和交替迭代法。通过3个交直流混联电网测试系统和南方电网实际系统数据验证了潮流模型的有效性和潮流算法的准确性,结合系统负荷水平、系统强度、直流嵌入规模等因素对2种潮流计算方法的收敛性能和计算速度进行对比分析。研究结果表明,在含多类型直流的交直流混联电网中进行潮流计算时,统一迭代法的计算效率比交替迭代法高。     

Multi-Core CPU Parallel Power Flow Computation in AC/DC System Considering DC Control

In order to integrated the control mode of the High-Voltage Direct Current (HVDC) into the power flow solution method and make it applicable to large-scale AC/DC hybrid system, a multi-core CPU parallel power flow computation method was proposed. First, the mathematical model of HVDC system and the frequently-used control methods of converter are introduced, and then models that have not been considered by conventional power flow programs, such as the adjustment of converter transformer tap and reactive power control management of the converting station, are built. Next, the loop-iteration algorithm is proposed to simulate the conversion of the HVDC control modes, and the AC/DC sequential solution is adopted to solve the AC/DC hybrid power flow. To solve the low speed problem of power flow solution for large-scale systems containing multi-circuit two-terminal DC, this paper handles each circuit separately so that the parallel computation capability of multi-core CPU can be used to improve the computation speed. Finally, the accuracy of the algorithms is validated in a small-scale hybrid system with 5-node and 2-circuit DC, and the excellent convergence and computation efficiency of the algorithms are proved by a large-scale hybrid system with 9241-node and 60-circuit DC as well.     

Power injection modeling and optimal multiplier power flow algorithm for steady-state studies of unified power flow controllers

This paper presents an optimal multiplier based Newton-Raphson power flow algorithm for reliably and efficiently handling power systems with embedded flexible AC transmission systems (FACTS) devices such as unified power flow controllers (UPFCs). A power injection transformation of a two voltage source UPFC model is derived in rectangular form. After detailed analyses of issues in implementation of UPFCs in power flow programmes by various power flow algorithms, the optimal multiplier power flow method for ill-conditioned systems is adopted. The proposed UPFC model and power flow algorithm have been programmed and vigorously tested in a number of systems. The results on the IEEE 30-bus test system and a 306-bus practical system are reported and compared with conventional user defined model type programmes, which clearly illustrate the effectiveness of the proposed algorithm.     

采用直流和交流功率传输分布因子的输电权交易

对比分析了基于直流和交流潮流的功率传输分布因子，认为交流的功率传输分布因子更能准确反映系统运行点变化对潮流的影响。文中还把交流传输分布因子与基于交流潮流的输电权相结合，为我国实现交流模型下的输电权交易探索了新思路。IEEE 9节点算例表明了交流功率传输分布因子比直流功率传输分布因子具有更高的准确性及有效性。     

Representation of FACTS devices in power system economic dispatch

The main idea behind FACTS (flexible AC transmission system) is to use network parameters as controls to direct flow, thus eliminating problems caused by unwanted loop or parallel flows. The authors present a methodology for the representation of FACTS device such as phase shifters and series compensations in optimal power flow models. The proposed approach is based on, mathematical decomposition and network compensation, techniques. It is possible to incorporate existing optimal power flow algorithms, thus taking advantage of accumulated experience in optimization methods and reducing software development costs. A case study with a Brazilian-derived system is presented     

考虑平衡节点无功约束的潮流算法

从交流功率网络性质和电力系统网络参数结构2方面分析了常规潮流算法中需要选择基准节点和平衡节点的原因。根据连续潮流计算中发电机无功约束出现的节点类型转换现象,提出了通过转换平衡节点类型来解决平衡机无功约束的潮流算法。通过对负荷节点功率变动态导纳处理,解决了电力系统天网性质造成的节点导纳矩阵病态问题,弥补了常规潮流算法的不足,反映了节点电压是由所有节点注入功率共同维持的客观事实。IEEE多个算例验证了所提算法的正确性和合理性。     

适用于交直流混联受端电网的机组组合模型及算法

特高压直流双极闭锁后,受端电网可能出现频率降低、功率大范围转移等运行情况,甚至引起低频减载、线路越限等电网事故。针对上述问题,提出一种用于交直流混联受端电网的机组组合模型,考虑了直流闭锁后的一次调频容量约束和二次调频后节点电压、线路功率等电网运行约束条件,保证直流闭锁后电网频率和潮流仍可运行在合理范围内。根据模型特点,采用基于Benders分解的混合整数规划算法进行求解,得到直流最优输送容量、最优机组启停和出力计划,在充分消纳直流输送功率的同时提高了交直流受端电网运行的安全性。最后,通过改进后的10机39节点和江苏电网两个典型的交直流混联电网算例进行仿真计算,结果验证了所述模型和算法的正确性和有效性。     

Fuzzy Genetic Algorithm Approach for the Optimal Placement of Flexible AC Transmission Systems Devices in a Power System

Abstract—This article presents a novel approach for optimal flexible AC transmission systems devices planning in an interconnected power system under different loading conditions. The static VAR compensator and thyristor-controlled series capacitor are two types of flexible AC transmission systems devices considered for optimal power system operation. In the proposed approach, a fuzzy membership function is used to determine weak nodes in the power system for the placement of static VAR compensators as a flexible AC transmission systems device. The thyristor-controlled series capacitor is the other type of flexible AC transmission systems devices for which its positions are determined by the reactive power flow in lines. The genetic algorithm is used for the optimal setting of the power system variables, including flexible AC transmission systems devices. The proposed technique is compared with other optimization methods using different globally accepted evolutionary algorithms where the nodes or point of VAR compensation is determined by eigenvalue analysis, and the amount of flexible AC transmission systems devices is determined by evolutionary techniques, such as the genetic algorithm, differential evolution, and particle swarm optimization. The superiority of the proposed fuzzy-based optimization approach is established by the results and comparative analysis with other methods.     

交直流混合系统电压稳定问题综述

采用交直流输电已成为必然趋势,但高压直流输电(HVDC)也给系统带来了不良的负荷特性,使得换流站交流母线的电压稳定问题成为困扰直流输电系统正常运行的一个重要问题,特别在受端系统较弱时更是如此。为了寻找更好的方法来评价交直流系统电压稳定性,对交直流系统静态电压稳定性分析方法进行归纳,评价了它们的优缺点,提出从交直流系统潮流计算方法和电压崩溃点计算方法两方面来改进分析方法。在交直流系统动态电压稳定性分析中,对建模的现状和存在的问题以及动态负荷对电压稳定的影响方面进行了描述,明确了建模要考虑动态负荷,既能描述换流器换相失败的动态特性,又要能用于求解大规模交直流系统。最后从交流系统和直流系统两方面讨论了防止电压失稳的措施。     

柔性交流输电系统交直流潮流可靠性评估模型

根据串联补偿器(TCSC)、晶闸管控制移相器(TCPST)和统一潮流控制器(UPFC)的工作原理,从交流和直流潮流的视角建立了潮流计算和最优负荷削减模型,采用状态枚举法在RBTS可靠性测试系统中进行分析和验证,结果表明采用交流潮流模型能更准确评估FACTS元件对系统可靠性的影响;而直流潮流模型计算耗时较少,且当节点电压约束不是刚性约束时,所得结果与交流潮流模型结果相近.