一个实用的程控增益放大电路

介绍一种程控增益放大电路，并给出了与８０９８单片机构成数据采集系统的实例。     

浅谈半导体电路的可靠性

分析了半导体电路不可靠的原因，并提出正确处理电路中的接触问题和防止干扰是保证电路可靠地工作的关键。     

ICL7135与单片机的一种连接电路

本文介绍利用ICL7135(国产型号5G7135)的位扫描信号DS 的变化,减少连线数目,与单片机连接的一种电路形式。     

一种实时变增益放大电路

本文提出了一种实时变增益放大电路，较详细的分析了其工作原理，给出了某些必要的波形图和参数计算公式，具有一定的实用价值。     

一种性能优良的AGC电路

讨论了自动增益控制电路的工作原理及类型,重点讨论了一种性能优良的自动增益控制电路的工作原理及电路实现。该电路具有增益高、动态范围大、频带宽、电路结构简单、易于实现等特点,可用于光纤通信、微波通信、卫星通信等接收系统。     

实时数控增益调整与浮点ADC电路

本文提出了一种实时数控增益调整与浮点ADC 电路结构,并给出了三种具有工程意义的实现方案,最后比较了三种方案的特点。     

改进双环DLL电路

文中介绍延时锁相环(DLL),并在开环和闭环DLL电路的基础上提出改进的双环DLL电路,给出设计电路和PSpise仿真结果.     

基于电路分块方法的超大规模集成电路测试技术

随着集成电路工艺和规模的飞速发展,使得VLSI测试变得日益困难,因此测试技术成为VLSI领域的一个重要研究课题。在分析VLSI测试的瓶颈问题基础上,介绍了几种电路分块算法,分析了分块算法对于VLSI测试的必要性。利用分块算法将原始电路划分为若干子块有利于采用不同BIST结构对子块进行测试,使得一定时间内电路翻转次数降低,而功耗也随之降低;通过比较并行BIST和扫描BIST的实验结果,发现并行BIST获得的系统故障覆盖率高于扫描BIST。     

A genetic algorithm for the optimal sequential partitioning problem

The optimal sequential problem is defined as the problem of finding the minimum cost partition of the nodes of a directed acyclic graph into subsets of a given size, subject to the constraint that the precedence relationships among the elements are satisfied. A heuristic algorithm based on tabu search has been proposed for this problem [2]. However, there is a tendency for the solutions obtained by tabu search to become trapped in bad local optima in parallel graphs with random edge costs. In this paper we present a genetic algorithm for the optimal sequential partitioning problem. We develop an effective two‐point partial order crossover satisfying sequential conditions, which preserve better blocks that have a larger sum of edge costs. In this crossover we introduce the roulette selection method to escape local optima. We also assess the effectiveness of the algorithm. The results show that this proposed algorithm outperforms any other algorithm using tabu search in terms of solution quality. © 2001 Scripta Technica, Electr Eng Jpn, 135(4): 43–51, 2001     

对断路器分(合)闸保持回路的一点改进

首先肯定目前使用的断路器操作装置中分(合)闸保持回路的设计思想和优点．分析了在运行中遇到的实际问题和可能造成的后果,提出在断路器分(合)闸回路中增加分(合)闸超时继电器的建议,改进后的回路对提高断路器操作回路及辅助设备的运行可靠性具有良好的作用。     

800 kV断路器电机控制回路的改进

断路器是发电厂及变电所用来接通或断开电路的重要电气设备之一,尤其是在电力系统发生短路故障时,通过断路器迅速动作将故障点切除。断路器工作性能好坏除了与本身的电气、机械、绝缘等性能有关外,还与其控制、保护及二次回路接线是否完善合理有很大关系。本文对750kV断路器储能电机控制回路进行详细分析,针对断路器出现分合闸闭锁的问题,提出了相应的改进措施和注意事项。     

二次回路及接线探讨

针对电力系统二次回路及继电保护调试进行了具体分析,供继电保护人员参考借鉴。     

220kV主变防跳回路及机构二次回路改造

对220kV红果变1号主变高压侧断路器与保护装置防跳回路不完善所带来的隐患进行可行性改造。     

Improvement of border characteristics of jointless track circuit

The track circuit uses the rail as part of the circuit. The purposes of the track circuit are (1) to detect the train, (2) to transmit signals to the train, and (3) to detect rail breaks. There are two types of track circuit. One uses insulation joints at the end of the circuit, and the other is jointless. The insulation joint requires much effort to maintain and control. Furthermore, it is extremely expensive, and uses an insulation material, which is one of the weak points of the rail track. There are some methods for constructing a jointless track circuit, but they have several problems. The biggest one is that the border of the track circuits becomes fuzzy. Another is the interference of multiple track circuit signals. Nevertheless, jointless track circuits have high priority. First, they do not demand an insulation joint and impedance bonds. Second, they are very easy to divide. Jointless track circuits are used for sharp curves where it is impossible to install insulation joints on the Shinkansen line. Also, several conventional lines and private railways use this system. Furthermore, several European high‐speed train systems also use jointless track circuits. Regarding Japan Railway, short‐distance track circuits for level crossing control are jointless, but normal track circuits have insulation joints, because there is a legal restriction on track circuit border ambiguity. To solve this problem, the author worked out a simple jointless track circuit only with induction coils, whose border characteristics are excellent. Furthermore, it does not have a strong frequency characteristic and it can be applied to any frequency. In this paper, a new type of jointless track circuit is proposed and theoretically analyzed, and basic experiments are reported. © 1999 Scripta Technica, Electr Eng Jpn, 127(4): 64–76, 1999     

基于MSHC继电保护一体化智能分区算法的研究

继电保护一体化图形拼接后电网规模不断扩大,运行方式越发复杂,继电保护整定计算不可避免地存在计算维数过高,计算量过大且求解效率过低等问题。深入研究一体化继电保护图形拼接的特点,提出了一种基于Mean Shift算法和层次聚类算法的MSHC继电保护一体化图形智能分区方法。根据割集最小、互感支路处于同一个子区域、子区域内厂站个数适中的三个厂站划分准则确定最优厂站分区方法。最后通过实际电网算例验证了该方法的快速性及有效性。     

一种开路电压和短路电流相结合的MPPT算法研究

为了能够有效地提高光伏发电系统的最大输出功率,根据光伏电池的输出特性和数学模型,提出了一种新型MPPT算法,即开路电压和短路电流相结合的MPPT算法。利用开路电压、短路电流和S-function函数快速解得最大功率点。针对不断变化的外界环境会给引入该算法的光伏系统带来频繁扰动,以及该算法在理论推导过程中采用了大量的估算算法,因此在该算法中引入阈值电流?I和微变步长扰动法。阈值电流?I降低了系统的扰动,减少能量的损失,微变步长扰动法进一步的修正了系统的最大功率点,解决了因理论估算而带来的误差问题。实验证明,引入了阈值电流和微变步长扰动法的开路电压和短路电流相结合的MPPT算法能快速、准确的跟踪最大功率点,提高转换效率。     

西门子高压开关二次回路的改进

针对西门子开关二次回路及在韶关系统使用中所出现的一些问题 ,提出相应的的改进措施。