高电压真空断路器温升影响因素的仿真研究

以一种高电压真空断路器模型为研究对象,对影响真空断路器温升的散热表面对流换热系数、动静触头接触点半径、接触点位置以及导电杆的半径4种因素进行了仿真研究。研究结果表明,在考虑散热表面辐射和不考虑辐射两种情况下,动、静触头接触处的温度差别在5%以内,而考虑散热表面的辐射后,接线端子的温度下降了14%。真空断路器温升随着动静触头接触点半径的增大迅速降低而与接触点位置无关,但当接触点半径增大至2 mm以后,温升降低趋势已不明显。真空断路器温升随着导电杆半径的增大而降低,其中触头接触处温度降低的趋势最为显著,但当导电杆半径增大至25 mm以后,温升降低趋势已不明显。

高电压半导体起爆器

制造了一种新的高电压半导体起爆器（HVSCI），并在陆军研究实验室进行了测试。作为结构设计、生产制造项目的一部分，对HVSCI的概念进行了调研，并用500V的击穿电压来起爆非起爆药或猛炸药的方式，对其进行了射频（RF）安全半导体起爆器（SCI）试验。用一个双面抛光的硅膜构成了一个背对背（back-to-back)扩散型二极管装置，其击穿电压为300V。选用300V击穿电压水平是为了进行“概念证明”实验，以便将其发火结果直接与以前专为海军保护PHALANX近程武器系统（CIWS）炮弹而制造的、较低电压结构产品的发火结果相比较。初期300V HVSCI装置已经在试验中，以便判定它们是否能可靠起爆二级炸药如PETN或HNS。类似于这种装置的、有较代正向击穿电压（约15V）的SCI，目前正处于鉴定阶段，它可用于海军PHALANX CIW 20mm的炮弹上；于此同时还研制了一种M167底火。如果海军的实验能够按计划进行，那么在RF有可能引起炮弹安全问题的环境中，M167底火很可能取代RF－敏感M52底火。

面向工程的高压电器制造执行系统设计与应用

从制造执行系统角度分析产品物化及工程化业务过程,提出以质量统计和追溯为先导,实现装备全生命周期可靠运行的系统架构。建立关键重要零部件(关重件)加工,整机装配、试验和交付运维的过程信息描述模型。基于现场智能终端和商业化软件系统的定制开发,在西电集团的子公司进行了项目实施与方案可行性验证。

基于模型预测控制的接触器开关弹跳抑制研究

该文立足于ABB同步开关技术前沿,基于运动轨迹模型预测进行一类接触器通用弹跳抑制策略研究,旨在不改变接触器自身机械结构参数的前提下从算法角度实现永磁接触器的弹跳控制。核心在于建立永磁接触器运动轨迹的动力学方程,通过模型求解探索接触器弹跳发生的数学机理,对接触器驱动电压的幅值与作用时间进行模型预测控制(model predictive control,MPC)预测,以响应时间最短为优化准则,确保动触头与静触头相接触时速度为零,据此给出驱动电压的取值准则。以某10k V电网母线PT烧毁等严重影响电网安全稳定运行的难题为背景进行接触器弹跳抑制研究,实验表明,所开发MPC策略可有效降低高电压补偿器接触器弹跳导致的涌流冲击,可为开发具有中国特色的同步开关技术提供参考基础。

一种0.8V低电源电压带隙基准电路的设计

提出了一种工作在低电源电压下的带隙基准电路。通过温度补偿电流的采集电路,突破了电阻分流式低压带隙基准[1]最低工作电压0.95 V的限制。基于SMIC 0.18μm工艺的Hspice仿真测试显示,电路的可靠工作电压最低可为0.8 V,且功耗仅为40μW,电源抑制比为69.5 dB@1 kHz;同时,在-20℃到100℃的温度范围内,输出电压的相关系数只有0.013 mV/K。

A Novel High-Voltage Detector Integrated into SPIC by Using FFLR

A novel high voltage detector that can be integrated into SPIC (Smart Power IC) is proposed.The structure is designed on the basis of normal junction terminal technique of FFLR (Floating Field Limiting Rings) system.The field limiting ring as a voltage divider,is used to optimize the surface field.The voltage of main junction increases from 0 to a high value,while the utmost ring is designed to vary within a small range,which can be handled by using low voltage logic circuits.An example of 400V rings system is analyzed and simulated for this structure.The results prove that the high voltage detector can detect high voltage in SPIC.The structure can be integrated into SPIC.Besides,it is compatible with CMOS or BCD(Bipolar CMOS Dmos) technology,without any additional processes required.

3D Macro-Micro-Mesoporous FeC2O4/Graphene Hydrogel Electrode for High-Performance 2.5 V Aqueous Asymmetric Supercapacitors

Distinguished from commonly used Fe2O3 and Fe3O4,a three-dimensional multilevel macromicro-mesoporous structure of FeC2O4/graphene composite has been prepared as binderfree electrode for supercapacitors.The as-prepared materials are composed of macroporous graphene and microporous/mesoporous ferrous oxalate.Generally,the decomposition voltage of water is 1.23 V and the practical voltage window limit is about 2 V for asymmetric supercapacitors in aqueous electrolytes.When FeC2O4/rGO hydrogel was used as the negative electrode and a pure rGO hydrogel was used as the positive electrode,the asymmetrical supercapacitor voltage window raised to 1.7 V in KOH(1.0 mol/L)electrolyte and reached up to 2.5 V in a neutral aqueous Na2SO4(1.0 mol/L)electrolyte.Correspondingly it also exhibits a high performance with an energy density of 59.7 Wh/kg.By means of combining a metal oxide that owns micro-mesoporous structure with graphene,this work provides a new opportunity for preparing high-voltage aqueous asymmetric supercapacitors without addition of conductive agent and binder.

Design of High-voltage Electrostatic Generator Based on STM32

This paper intreduced a high-precision high-voltage elec- trostatic generator which utilized STM32F103 as the main coutroller. The hardware and software design of the system were detailed. The full use of ample on-chip resources of STM32F103, such as ADC and the PWM output of timer, contributed to the small size and low cost of the system. The 16-bit PWM signals, generated by the timer on chip, served to adjust the our-put voltage accurately. The tot~ screen was responsible for the setting and display of output voltage, and the friendly humawcomptaer interaction was built. Experimental results indicated that this high-voltage static generator was of high precision and great practicability for application.

Noise-Induced Transition in a Voltage-Controlled Oscillator Neuron Model

In the presence of Gaussian white noise,we study the properties of voltage-controlled oscillator neuronmodel and discuss the effects of the additive and multiplicative noise.It is found that the additive noise can accelerate andcounterwork the firing of neuron,which depends on the value of central frequency of neuron itself,while multiplicativenoise can induce the continuous change or mutation of membrane potential.

High Voltage Breaker Current Monitoring and FaultDiagnosis System Based on Fiber Current Sensor

Abstract: The current measuring principle, the hardware structure and the software functions of a high voltage breaker current monitoring and fault diagnosis system are introduced. A simple algorithm for calculating the current effective value is given. The cut - off characteristics of the breaker are classified. This system can provide a foundation for reasonably determining the breaker service period.

The Design of the TZ-2 High Voltage Modulator

This paper introduces the design of the TZ-2 high voltage modulator for electron cyclotron resonance heating （ECRH） on HL-2A tokamak. The high voltage power supplies （HVPS） for the cyclotron have to operate advantageously and flexibly, with high stabilization and good insulation to high-voltage. Moreover, the HVPS must carry out the function of protection quickly, for insure the security of people and devices in the experiment on HL-2A. In this year, the HVPS with these modulators satisfies the requirement of the experiment of HL-2A.

Research on Multi Level Dynamic Voltage Compensator based on MMC

The modular multilevel converter （MMC） is a highly modular, easy to expand; the output voltage waveform is good, especially suitable for application in high voltage power system. This article first introduces the circuit topology and principle of MMC, and the main technical characteristics of MMC. And according to the relationship between the drop power voltage and the load power factor, proposed three working modes of the minimum energy compensation strategy. It is shown that MMC has good application prospect in future medium or high- voltage high power applications, especially be one of candidates for HVDC system application.

Analysis of the Correlation between the Level of Contact Degradation and the Dynamic Resistance Curve in Circuit Breakers

The DRM （dynamic contact resistance measurement） in high voltage circuit breakers is a manner of evaluating the internal ageing condition of the chamber. DRM is similar to static contact resistance measurement testing, but instead of measuring a single value when the breaker contacts are closed （static value）, the ohmic resistance is measured at various contact positions, from the beginning of the contact opening until a complete separation of the contacts. The relationship between the contact resistances of the new circuit breaker and the ageing circuit breaker in operation provides subsidy for the evaluation of both the main and arcing contact conditions. This research aims to analyze the correlation between the various levels of degradation of the contacts and the configuration of the DRM curve. This work considers curve samples from new acceleration tests. breaker chamber contacts and different levels of degradation by

Overvoltage Suppression for UHV Transmission Lines

The overvoltage phenomena of ultra high voltage (UHV) transmission lines are analyzed and verified by EMTDC/PSCAD simulation. Referring to the theoretical analyses and operating experiences of extra high voltage (EHV) transmission lines in China and UHV transmission lines in Russia and Japan, the methods to suppress the internal overvoltage in UHV transmission lines by protection and control strategies are discussed. Through the cooperation among the recloser, shunt reactor, tripping and closing resistance, and metal oxide varistor(MOV), the overvoltage can be restrained within an acceptable level.

High Voltage High Frequency Power Transformer for Pulsed Power Applications

This paper presents a new topology for a High Voltage （HV） 50 kV, High Frequency （HF） 20 kHz, multi-cored transformer suitable for use in pulsed power application systems. The main requirements are： high voltage capability, small size and weight. The HV, HF transformer is the main critical block of a high frequency power converter system. The transformer must have high electrical efficiency and in the proposed approach has to be optimized by the number of the cores. The transformer concept has been investigated analytically and through software simulations and experiments. This paper introduces the transformer topology and discusses the design procedure. Experimental measurements to predict core losses are also presented. The losses of epoxy coated nanocrystalline are compared to the losses in a new uncoated core.

Development of Fiber Optically Driven Instrument for High-voltage Line Current

The measurement theorem of fiber optically driven instrument for high-voltage line current is presented. The PLL voltage-frequency-narrow pulse principle and its micro-consumption mechanism are proposed, followed by analysis on the two main factors affecting PLL measurement precision. A software design scheme using 80C196KB micro-controller is introduced. The experiment result is satisfactory.

Analysis of Drain Modulation for High Voltage GaN Power Amplifier Considering Parasitics

For high-voltage and high-power Gallium Nitride(GaN)power amplifiers,a drain modulation circuit with rapid rise and fall time is proposed in this paper.To decrease the rise and fall time,the high-side bootstrap drive circuit with an auxiliary discharge switch is proposed.The effect of the parasitics is analyzed based on calculation and the parallel bonding is proposed.The storage capacitance of power supply is calculated quantitatively to provide large pulse current.To ensure safe operation of the power amplifier,the circuit topology with the dead-time control and sequential control is proposed.Finally,a prototype is built to verify the drain modulation circuit design.The experiments prove that the rise time and fall time of the output pulse signal are both less than 100 ns.

Brushless Doubly-Fed Induction Machine as a Variable Frequency Transformer

VFT （variable frequency transformer） has been recently used as art alternative to HVDC （high voltage direct current） to control power flow between asynchronous networks. VFT consumes less reactive power than a back-to-back HVDC system, provides faster initial transient recovery, and has better natural damping capability. VFT is simply a DFIM （doubly-fed induction machine） where the machine torque controls the power flow from stator to rotor and vice versa. The main disadvantage of this VFT is the slip rings and brushes required for the rotor circuit, especially in bulk power transmission. The BDFM （brushless doubly-fed machine） with nested cage rotor machine is proved to be a comparable alternative to conventional DFIM in many applications with the advantage that all windings being in the stator frame with fixed output terminals. In this paper, the BDFM is used as a BVFT （brushless variable frequency transformer）. A prototype machine is designed and simulated to verify the system validity.

High-Frequency Digital Controller Applied to Voltage Regulator Modules

Digital controllers are an interesting option for the next voltage regulator module （VRM） generation due to their wide programming possibilities. This paper discloses a very interested candidate to control DC-DC power converters, the Digital Signal Controller （DSC）. For that matter, a study was done by carrying out simulations and experimental results. Moreover, an additional voltage-input feed-forward （IVFF） algorithm is given in order to show the benefits of this technology. Finally, a complete analysis of the quantization effect is presented, and its influence over the controller performance is included.

Transitional Recovery Voltages at Capacitive Currents Switching-off by Vacuum and SF6 Circuit-Breakers

Results of calculation the recovery voltages conditioned by capacitive currents switching-off by high voltage vacuum and auto-compression （SF6） circuit-breakers are presented in the article. The purpose of research was evaluating the maximum values of recovery voltages and also studying the dependence of recovery voltages on some influencing factors, especially on type of circuit-breaker presented in numerical models with its dielectric strength restoration law, chopping current and operation time. The research was carried out with using computer simulation.