10kM配电带电作业新软型遮蔽罩的研制

10 k V配电带电作业用软质绝缘遮蔽罩是配电带电作业的重要工具之一 ;本文分析了其研制技术方案、选材及形状设计 ,并提出进一步完善和改进意见     

一种新型配电网在线监测装置的研制

为解决配电网中传统的故障指示器无法准确识别小电流单相接地故障与定位问题,引入了基于暂态量零模的参数识别法,研制了一种应用于配电网的新型在线监测装置。三相探头通过自取电模块从线路电流中获取能量为其自身提供电源,利用罗氏线圈采集线路电流,采用非接触式电压传感测量线路电压,通过一种基于近距离无线通信的分布式同步录波方法实现故障波形的录制。通信终端汇总故障波形并对其进行零序矢量合成,自动完成对单相接地故障的识别与告警指示,为解决小电流单相接地故障定位和提升配网自动化覆盖率提供了一种新的解决方法。现场实验结果证明了该装置的实用性和对小电流单相接地故障检测与定位的准确性。     

Development of current limiting arcing horn for prevention oflightning faults on distribution lines

Wire breakage by arc fusion due to lightning flashovers has become a serious problem in Japan as a result of the widespread use of insulated wires as distribution lines. To solve this problem, a current-limiting arcing horn that has a nonlinear resistor element of zinc oxide has been developed. With this element the power follow current is interrupted and conductor arc fusion is prevented. Even in the case of bare wires, this device effectively prevents power-supply service interruptions. The design and performance of the device and its ability to prevent lightning faults on actual distribution lines are described     

新型微机式电流方向继电器研究

提出了一种新型微机式方向继电器即电流方向继电器,分析了它的基本工作原理、硬件构成及基本的实现方法,还分析了具体实现过程中可能遇到的问题及其对策。这种方向继电器只需要检测电流值和电压的相位信息就可以实现短路故障方向的正确判别。由于它不需要检测电压信号的值,所以具有结构简单、实现容易、成本较低、动作较快、工作可靠等优点。此外,该型方向继电器的动作范围和灵敏角的设置非常简单、方便、灵活,而且其电压死区问题得到了很好的解决。     

新型微机式电流方向继电器研究

提出了一种新型微机式方向继电器即电流方向继电器,分析了它的基本工作原理、硬件构成及基本的实现方法,还分析了具体实现过程中可能遇到的问题及其对策.这种方向继电器只需要检测电流值和电压的相位信息就可以实现短路故障方向的正确判别.由于它不需要检测电压信号的值,所以具有结构简单、实现容易、成本较低、动作较快、工作可靠等优点.此外,该型方向继电器的动作范围和灵敏角的设置非常简单、方便、灵活,而且其电压死区问题得到了很好的解决.     

超导限流器基本概念和发展趋势

超导限流器是多年以来人们在超导电力技术领域的研究焦点之一,也是被认为最有可能率先实现工业化应用的超导电力设备。本文在介绍超导限流器的基本概念、组成要素和功能特点的基础上,讨论了超导限流器设计和应用相关的一些重要技术参数和性能指标。文章还较系统地分析了电阻型和饱和铁心型两种目前发展水平较高的超导限流器的工作原理和应用情况,并比较了两者的优缺点。随着性能的进一步完善,可靠性和可用性的进一步提高,超导限流器有可能成为理想的电网短路故障限流装置。作者期待在不远的将来超导限流器会在各种电网中得到广泛的应用,并由此推动电网的深刻技术革命。     

配电网宽带数字通信设备研制

提出了一种基于OFDM技术的配电网宽带数字通信设备研制方案，详细地分析了系统中每一个关键功能模块实现方法，讨论了利用DSP和FPGA技术实现的核心功能模块，例如，IFFT／FFT，同步电路、自适应均衡电路、抗配电网输电线上突发干扰的纠错方法等。     

Integration of fault current limiters on power systems for voltage quality improvement

Voltage sags and the associated phase angle jumps are resulting in numerous production outages due to the tripping of adjustable speed drives and sensitive process controls. In order to eliminate the enormous economic losses associated with these outages, utilities are actively looking for possible sag mitigation solutions. This paper focuses on the proper selection and design of suitable solid-state Fault Current Limiter configurations for application on the power systems to mitigate voltage sags in term of voltage magnitudes and phase angle jumps. Sensitivity analysis was also performed to determine the effects of varying FCL parameters on its performance in term of voltage supporting capability, phase angle jump reduction and fault current reduction.     

T接线路电流纵差保护新判据研究

根据T接线路的特点,提出一种基于故障分量的电流纵差保护新判据.该判据在保证外部故障稳定性的前提下,对内部故障具有灵敏度高、允许过渡电阻能力强等特点,动作性能不受负荷电流的影响,适应于有电流流出的内部故障情况.文章给出了该判据的理论分析、应用条件和仿真结果.     

T接线路电流纵差保护新判据研究

根据T接线路的特点 ,提出一种基于故障分量的电流纵差保护新判据。该判据在保证外部故障稳定性的前提下 ,对内部故障具有灵敏度高、允许过渡电阻能力强等特点 ,动作性能不受负荷电流的影响 ,适应于有电流流出的内部故障情况。文章给出了该判据的理论分析、应用条件和仿真结果。     

Development of a current detection type cable fault locator

A cable fault location instrument based on the detection of traveling wave currents was developed. It is different from the conventional pulse radar method based on voltage detection. Measurement is automated, and the distance to the fault point is displayed by merely pushing a switch. In a branched or crossbonded line, the fault point can be located without interference from the branched or the crossbonded point. Tests performed in both real and simulated lines confirmed the practical utility of this instrument     

无源型磁光电流互感器在110 kV线路的应用

河南新安县在某变电所110 kV出线间隔的无油化改造中,选用了无源型磁光电流互感器,该装置属于电流互感器的最新一代产品。总结运行实践经验,介绍了该装置的优越性,简述了其工作原理、装置结构及技术参数选择。说明了无源型磁光电流互感器适应电力系统自动化的发展,科技含量高,已达到实用化程度。     

Analysis of ground fault current distribution along nonuniform multi-section lines

In case of a substation supplied by a combined overhead-cable line, most of the ground fault current flows through the cable sheaths and discharges into the soil surrounding the point of discontinuity, where cables are connected to the overhead line. In the paper a new method is presented for computing the ground fault current distribution in case of feeding line consisting of two or more different sections, i.e. part overhead and part underground cable. Besides the calculation of the earth current at the fault location, the leakage current at the transit/transition stations as well as at the overhead line towers can be evaluated, in order to ensure proper safety conditions. Based on the two-port theory, the method allows to take into account all the relevant conductively and inductively coupled parameters which take part to the fault current distribution. A computer program based on the proposed method has been developed and some application examples are reported.     

基于线圈电流反馈的新型节能接触器的研制

针对传统接触器交流电磁机构和直流电磁机构存在的不足,提出电磁线圈电流反馈的恒流控制策略,研究控制器主电路的工作原理和起动过程,并设计相关的硬件电路。实验结果表明,新型接触器能实现宽范围交流或直流供电电压输入并可靠吸合,在节能、降噪、抑制触头弹跳和提高电寿命等方面具有很大优势。     

超导限流器对电力系统继电保护和暂态稳定的影响

电力系统的高速发展导致了系统短路电流水平急剧增加,超导限流器SFCL(Superconducting Fault Current Limiter)是目前最理想的限流装置.本文详细介绍了含有超导限流器的电力系统的功率特性,并利用等面积准则分析了系统暂态过程,在理论上解释了超导限流器对电力系统暂态稳定的影响;由于超导限流器在电力系统中应用会对继电保护产生影响,尤其是对于距离保护影响较为明显,本文后部分详细分析了超导限流器对距离保护的影响,提出了新的整定方法,最后通过仿真实例对新的方法进行了验证.     

一种新型光学电流传感器结构设计与仿真研究

本文设计对称光程反射式光学电流传感器实验系统,使用COMSOL多模场耦合仿真软件对所设计的光学传感系统的传输场进行模拟仿真,得到对称光程反射式光学电流传感器对法拉第磁光效应的响应度,其理论灵敏度高于传统结构的灵敏度580倍。未来将基于所建立的实验系统对传感器的潜在应用做进一步的深入研究。     

Fiber-optic-based current and Voltage measuring system for high-Voltage distribution lines

A system for temporary measurement of voltage and current simultaneously in high-voltage distribution lines was developed. The sensing heads use a resistive divider and a magnetic pickup for sampling voltage and current, respectively. A self-powered transmitter converts both signals into a pulse-frequency-modulated optical signal for transmission in multimode optical fiber. At ground potential, the optical signal is received and demodulated back into voltage and current signals. Then, a microcontroller calculates V and I for the three phases as well as VA, power factor, and watt-hour, storing these in memory. The system exhibits all data in instantaneous mode and stores 5-min mean values of a period of up to ten days. Optionally, the data can be collected by a personal computer through a standard RS-232C serial port. The system linearity for both current and voltage is better than 2% in the range of 0 to 800 A and 0 to 15 kV, respectively. It can be installed by live-line techniques in less than 10 min, without de-energizing the line.     

新型起动用免维护铅酸蓄电池的研制

新型起动用免维护铅酸蓄电池是一种带有流动电解液的起动用密封电池 ,电池在设计及生产过程中采用 :优化设计结构、铅钙合金板栅、矮型极板、PE隔板、过量电解液、迷宫式排气装置及先进的工艺配方等技术。产品具有免维护、起动倍率高 (低温起动倍率可高达 8～1 1C2 0 )、寿命长等特点 ,而容量、充电接受能力、深放电性能也有大幅度提高。本系列产品性能已达到 90年代先进水平 ,可作为目前市场上常规“少维护电池”的更新换代产品。由于解决了大批量生产中存在的各种问题 ,产品已投放市场。     

Multi objective optimal allocation of fault current limiters in power system

Transmission systems, connection of distributed generation to the grid are increased due to increase in power demands. This fact causes the increase in short circuit level of power networks. The occurrence of fault in such networks leads to large short circuit currents throughout the system, which may exceed the rating of existing circuit breakers and can damage system equipment. There are some approaches to reduce this fault current such as power network reinforcement and utilization of fault current limiter (FCLs) in power systems. Power system reinforcement is too difficult if not impractical. Therefore, the utilization of FCLs can provide an effective way to suppress fault currents. The effectiveness of FCL depends on the number of FCLs and their installation location. In this paper, a novel approach is presented to determine the optimal number and location of FCLs to improve the power network reliability and fault current reduction based on different conflicting objective functions. IEEE 39 BUS system and IEEE 57 BUS system are considered to evaluate the effectiveness and feasibility of the proposed method. The objective functions considered for the optimal allocation are reliability of power system, economic impact and short circuit current reduction. Unlike what has been previously done in literature, in this paper Pareto based optimization algorithms, namely non-dominated sorting algorithm, multiobjective particle swarm optimization and multiobjective evolutionary algorithm based on decomposition, are utilized to deal with this problem. The use of these methods made it possible to obtain the Pareto optimal front in which these objective functions are optimized simultaneously.     

基于图像识别技术的电机换向片自动检测系统的研制

本文设计了一种新型的基于图像识别技术的电机换向片自动检测系统,文章阐述了系统的工作原理及硬件构架,提出了适合本系统的图像处理算法,以VC 6.0为开发平台,完成了软件程序编写及系统控制界面设计,并对ZQDR-410型直流电机进行了实验,获得了数控机床的定位信号.结果表明该系统精度高、实时性强,能够保证换向片检测的质量,具有较强的实用价值.