A new method and instrument for touch and step voltage measurements

This paper describes a new method and instrument for measuring touch and step voltages near a grounding system, for example in and around a substation. The hardware, software, and testing procedures are an extension of the smart ground multimeter, developed under EPRI sponsorship. The instrument injects a transient electric current between the ground under testing and an auxiliary ground, and it measures ground potential differences (GPDs) at up to six locations. The GPD measurements are processed with software which rejects external noise using correlation methods. Subsequently, statistical estimation methods are used to extract the touch or step voltages from the thousands of measurement points normalized with the system short circuit capability. Knowledge of the short circuit capability of the substation allows the quick measurement of the touch and step voltages     

低噪声前置放大器有源器件的选择

根据噪声理论及等效噪声模型,本文推导了前置放大器的噪声特性指标.为了达到最佳噪声匹配,分析比较了双极型晶体管(BJT)、集成运放及场效应管(FET)的内阻、噪声特性及三种不同耦合方式的特点,从而总结出对于低内阻信号源较理想的前置放大器的有源器件是单级或多级并联双极型晶体管.     

An active microelectronics device for multiplex DNA analysis

Nanogen's approach to DNA analysis involves the development of a unique active microelectronic device that provides electronic control over a variety of molecular biological affinity reactions. The core technology is an automated programmable electronic matrix (APEX), which has the ability to transport, bind and separate charged molecules in an electric field generated on the surface of the device. This broad-based platform technology is potentially applicable for multiplexed DNA hybridizations, immunoassays, receptor binding assays, cell typing assays, enzyme assays, combinatorial synthesis of oligonucleotides and peptides, and nanoparticle manipulations. Nanogen's initial developmental focus is in the area of DNA probe diagnostics. Our proof of concept and initial DNA hybridization results indicate great potential for Nanogen's active device technology. The multiplex hybridization array formats now being developed are directed at providing rapid simultaneous testing from a microliter volume of patient samples, with better sensitivity and specificity than current assays. Nanogen active device technology offers a number of distinct advantages versus current DNA diagnostic technology and differentiates itself from other chip technologies in the following way: (1) electronic addressing transports DNA molecules by charge; (2) the electronic hybridization's concentration effect improves the DNA hybridization rate; and (3) electronic stringency control improves selectivity and discrimination of hybrids     

新型厂用电快速切换装置设计

通过对发电厂厂用电切换过程进行分析，提出一种新的厂用电快速切换原理，并同步研发出新型快速切换装置。该装置采用32位数字信号处理（DSP）芯片TMS320F2812作为核心处理器，切换过程快速、灵活，测量、控制、显示、录波功能完备，易操作，免维护。在配备了RS485和CAN通信接口的基础上，加装了USB2．0接口，使录波数据的采集和分析更加方便。目前，新装置已在实际应用中得到肯定。     

一种新型微机继电保护实验装置的研制

根据高校电力系统继电保护实验教学的需要,研制了一种适合高校实验教学用的微机保护实验装置,填补了国内高校微机保护实验装置的空白。该装置以16位MCU为中心,具有各类输入输出接口,并设有RS-232和USB通信接口。配有组态实验软件,人机界面友好,能方便进行各种继电保护原理实验和不同算法的比较。采用了简单灵活的JTAG口作为调试接口,并专门设计了易于拆卸的整机结构,便于实验者对微机保护实验装置及过程的全面了解。     

一种新型微机继电保护实验装置的研制

根据高校电力系统继电保护实验教学的需要,研制了一种适合高校实验教学用的微机保护实验装置,填补了国内高校微机保护实验装置的空白.该装置以16位MCU为中心,具有各类输入输出接口,并设有RS-232和USB通信接口.配有组态实验软件,人机界面友好,能方便进行各种继电保护原理实验和不同算法的比较.采用了简单灵活的JTAG口作为调试接口,并专门设计了易于拆卸的整机结构,便于实验者对微机保护实验装置及过程的全面了解.     

Knee extension dynamometer: a new device for dynamic isokinetic magnetic resonance spectroscopy experiments

In the present study we introduce a new device for exercise magnetic resonance spectroscopy (MRS). It operates in a standard whole-body scanner. Mechanical exertion unit allows maximal 10° to 15° short-arc knee extensions. The device operates hydraulically and is based on isokinetic movement. The force and work conducted are automatically controlled by the electronic control and computer unit. A small surface coil placed on the vastus medialis muscle allows the collection of spectra without interfering spectra from nearby resting muscles. The force used for the extensions can be followed simultaneously as a curve on the screen in the operator's room and the data is transferred to a personal computer for later analysis. Total work and fatigue percentage are also calculated by the device. It also allows the use of different isokinetic exercise protocols. The measurements of force proved reliable in repeat measurements using an isokinetic test device as a control.This device has been used clinically for over a year, is easy to operate, and offers reliable measurements. It is well suited to trials where muscle energy states versus time are followed since it allows noninvasive simultaneous quantification of muscle performance and collecting MRS spectra at rest, during exercise, and in the recovery phase.     

一种新型自动气象站触控屏交互式系统设计

设计了一种基于STM32的异步全双工串口通信（USART）的触控式显示屏人机交互式系统,应用于DZZ1‐2型新型自动气象站中。设备用户可通过该交互式系统直接对数据采集器进行数据查看、参数设置等操作,为DZZ1‐2型新型自动气象站的安装调试和维修维护提供极大的便利性。设计包括：硬件电路设计、用户 UI设计和嵌入式软件设计,重点讲述了用户UI的设计流程和嵌入式软件设计中USART中断函数的使用。试验结果及在广东省一年多的业务运行,证明该系统运行稳定、便捷可靠。     

一种新型防窃电装置的设计

有效遏制窃电行为具有重大意义,但目前缺乏可靠实用的防窃电手段.介绍了一种新型防窃电装置,该装置直接采集用户一次侧用电信息,作为判断窃电的依据,对该装置的功能及设计方法进行了说明,并详细说明介绍了从高压侧获取电源的方法.最后给出了防窃电实例证明该装置的实用性.     

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。     

A new sensing device for washing machines

A device is presented that is able to monitor the washing process, turning the washing machine into a closed-loop controlled machine. The device, based on light scattering to detect the different structure of surfactant micelles and emulsions, is able to understand the different situations occurring during the washing and determines when it is over. This creates savings of electric power, detergent, and water     

强磁场装置有源直流滤波器设计

对强磁场装置电源所需的有源直流滤波器ADF(Active DC Filter)进行了设计,利用脉宽调制(PWM)及并联有源滤波技术提出了新的滤波方案。给出了系统结构并对工作原理进行了说明,论述了该系统的设计方法。根据其实际负载特性,通过检测负载端电压,利用电流的PWM控制技术产生所需电流,通过对负载侧的滤波电容进行充、放电调整负载端电压,从而实现负载电流的低纹波。基于传递函数建立了该系统的数学模型,并对控制系统进行了详细的分析,分析表明该系统具有良好的快速跟踪性能及对谐波很好的抑制效果。最后,给出了仿真结果,验证了该有源滤波器的良好性能,尤其对低次谐波的抑制更为明显。     

一种新型一体化高压计量检定装置的研制

提出了一种兼顾单相、三相电压互感器和电流互感器以及电能表的一体化高压计量检定装置,具体提供了该检定装置的设计理念和构建的技术路线,并全面分析了该其测量不确定度来源。该一体化高压计量检定装置的研制成功,对解决国网公司最新确立的一、二次融合技术方案所需的电子式互感器、高压计量模块的检定具有重要意义。     

一种新型强油循环风冷变压器冷却自控装置的研制

分别从控制系统的硬件结构、软件设计及装置实现的功能等3个方面进行了论述。装置以变压器的负荷、油面温度与温度变化率相结合的控制策略进行冷却器的综合投切控制，以冷却器组的累计运行时间基本均衡为原则进行冷却器组循环控制。叙述了具有冷却器组自动投切定位功能的投入／切除模块的程序结构。装置还具有完善的保护功能、手动／自动功能、故障定位功能、信息显示功能、故障报警与跳闸功能等。实际运行表明，该装置运行可靠，控制准确，功能完善，并具有显著的节能效果。     

Haptic interaction of touch and proprioception: implications for neuroprosthetics

Somatosensation is divided into multiple discrete modalities that we think of separably: e.g., tactile, proprioceptive, and temperature sensation. However, in processes such as haptics,those modalities all interact. If one intended to artificially generate a sensation that could be used for stereognosis, for example, it would be crucial to understand these interactions. We are presently examining the relationship between tactile and proprioceptive modalities in this context. In this overview of some of our recent work, we show that signals that would normally be attributed to two of these systems separately, tactile contact and self-movement, interact both perceptually and physiologically in ways that complicate the understanding of haptic processing. In the first study described here, we show that a tactile illusion on the fingertips, the cutaneous rabbit effect, can be abolished by changing the posture of the fingers. We then discuss activity in primary somatosensory cortical neurons illustrating the interrelationship of tactile and postural signals. In this study, we used a robot-enhanced virtual environment to show that many neurons in primary somatosensory cortex with cutaneous receptive fields encode elements both of tactile contact and self-motion. We then show the results of studies examining the structure of the process which extracts the spatial location of the hand from proprioceptive signals. The structure of the spatial errors in these maps indicates that the proprioceptive-spatial map is stable but individually constructed.These seemingly disparate studies lead us to suggest that tactile sensation is encoded in a 2-D map, but one which undergoes continual dynamic modification by an underlying proprioceptive map. Understanding how the disparate signals that comprise the somatosensory system are processed to produce sensation is an important step in realizing the kind of seamless integration aspired to in neuroprosthetics.     

Design and control of RUPERT: a device for robotic upper extremity repetitive therapy.

The structural design, control system, and integrated biofeedback for a wearable exoskeletal robot for upper extremity stroke rehabilitation are presented. Assisted with clinical evaluation, designers, engineers, and scientists have built a device for robotic assisted upper extremity repetitive therapy (RUPERT). Intense, repetitive physical rehabilitation has been shown to be beneficial overcoming upper extremity deficits, but the therapy is labor intensive and expensive and difficult to evaluate quantitatively and objectively. The RUPERT is developed to provide a low cost, safe and easy-to-use, robotic-device to assist the patient and therapist to achieve more systematic therapy at home or in the clinic. The RUPERT has four actuated degrees-of-freedom driven by compliant and safe pneumatic muscles (PMs) on the shoulder, elbow, and wrist. They are programmed to actuate the device to extend the arm and move the arm in 3-D space. It is very important to note that gravity is not compensated and the daily tasks are practiced in a natural setting. Because the device is wearable and lightweight to increase portability, it can be worn standing or sitting providing therapy tasks that better mimic activities of daily living. The sensors feed back position and force information for quantitative evaluation of task performance. The device can also provide real-time, objective assessment of functional improvement. We have tested the device on stroke survivors performing two critical activities of daily living (ADL): reaching out and self feeding. The future improvement of the device involves increased degrees-of-freedom and interactive control to adapt to a user's physical conditions.     

新一代微机保护装置的设计与实现

本文在从微机保护的发展上提出了新型微机保护的方案,从软件和硬件上完成了新一代微机保护的设计和实现。实践表明将实时操作系统μC/OS-II与高性能DSP处理器TMS320F2812结合应用在嵌入式微机继电保护装置具有可靠、灵活、易于维护等优点。     

有源中点钳位型三电平逆变器开关器件损耗均衡调制方法

三电平有源中点钳位型(Three-Level Active Neutral-Point-Clamped,3L-ANPC)逆变器可以克服传统三电平逆变器内外层开关器件损耗不均衡的问题,但是其实现损耗均衡的控制方法,一般要求在线计算开关器件温度进行直接控制,或者实时采集开关器件温度进行反馈控制,实现过程比较复杂.为在实现损...     

新型混合式有源电力滤波器的控制方法

由于电力系统中使用了越来越多的电子设备,改善功率因数和消除电网侧的谐波电流便成为很重要的问题,为此,介绍了一种混合式电力补偿器（HPC）的自抗扰（ADRC）控制方法,该方法可以有效地改善功率因数和消除谐波——将消除谐波问题转化成系统跟踪给定相位正弦信号问题,利用扩展状态观测器（ESO）估计干扰,并进行补偿,利用非线性状态误差反馈器（NLSEF）实现参考信号的跟踪。这种控制策略的一个显著特点是不需要精确地测量谐波。基于这种控制方法的混合式电力补偿器对于不同的典型负载、负荷侧电流大小和相位的变化都有很强的适应性。最后,通过对不同负载情况进行仿真,结果证明了这种控制方法的有效性。     

一种智能变电站新型双网冗余设备及实现

为了解决当前智能变电站自动化系统内网络冗余存在的问题,提出了一种变电站内新型网络冗余的设备(双网冗余接口盒及双网冗余接口卡)软硬件实现方法,将变电站内部保护测控等装置通过双网冗余接口设备接入符合IEC62439-3规范的PRP/HSR网络实现新型双网冗余。采用FPGA+CPU的硬件构架,通过利用在FPGA设计出以太网通信控制MAC模块、PRP/HSR模块、存储控制模块、多路报文转发控制模块协同完成变电站系统内以太网报文冗余处理。试验证明,所研制的冗余设备满足电力系统保护装置对于速动性的要求,在智能变电站自动化系统内具有较好的实用性。