四代卫星通信的特点及应用前景探讨外文翻译.doc

毕业设计（论文）外文文献翻译毕业设计（论文）题目四代卫星通信的特点及应用前景探讨翻译（1）题目自给的功率源应用于数字继电器的应用翻译（2）题目软件设计的数字电源基于实验室Windows /CVI外文翻译1：自给的功率源应用于数字继电器的设计 摘要目前,绝大多数的继电保护设备依赖于可靠的现场电源工作。它的电源的工作和操作电路要求变电站或配电间提供交流或直流电源。这介绍了一种自供电电源应用于数字继电器的设计。获得的能量直接从电力线路通过一些特制的铁芯电流互感器(CT)。这个信号,输出的整流电路,是输入信号的采样电路,电容器也可以充电储能在相同的时间。一个集成开关调节器改变电压信号,终端的储能电容器,为稳定的直流电电压信号,直流稳压电源的数字继电器。这种方法可以避免饱和问题的核心圈当一次电流变化在一个更大的范围内通过增加空气差距在核心圈和引入气隙磁阻。所以,后端电路大大简化和提高了可靠性。电源模块可以用于电力系统继电保护与10千伏电压及以上级别和在线监测设备,具有广阔的应用前景。 关键字-自动提供电源;铁芯电流变压器(CT);数字继电器;气隙磁阻;能源存储电容器一、 介绍 一直以来,继电保护装置的电源的工作和操作电路要求变电站或配电间提供交流或直流电源。如果没有权力在现场,继电保护设备不可以工作。没有电源就像一些RTU设备用于配电自动化它能工作吗?它可以自供电功率从高压线吗?目前,一个类别的设备开发公司德国German SEG出现在市场,称为数字自供电的过电流继电器。这样的设备不需要外部力量供应;电源是从TA直接获取安装在高压线路上。这个概念,把权力从TA作为电源工作单元回路和操作,是创新的自供电的数字继电器。出现的数字自供电的过电流继电器显示在图1。 一些研究人员提出了多种供电方式,比如太阳能与锂电池功率,激光功率,微波功率和在线获得能源使用特殊的TA等2 - 4。其中,从特殊的TA获取能源这个方法安装在高压侧给在线访问电力电子电路是最有前途的电源。然而,有一些问题需要解决关于这个权力供应方法,主要包括5:(1)当一次电流在较大的范围内变化(1% 120%)如何确保对电子电路稳定部分的电压。这是目前一个迫切需要解决的问题;(2)稳定性问题方法来获取功率;(3)这个问题的核心，饱和线圈。要解决这些问题,本文提出一 种电源解决方案用于数字继电器。这种方法可以避免饱和问题的核心圈当一次电流在一个更大的范围内改变通过增加气隙的核心线圈和引入气隙磁阻。所以,后端电路得大大简化和可靠性改进。此外,锂离子电池包中添加了在线获取电源,使其电力供应有更多可靠的。没有死区当天24小时内,这使得电源模块已广泛应用。 康秋兰,刘曙光,李彭芬学校的电子信息采集。中国西安理工大学 kangqiulan2006图1 外观数字自供电的过电流继电器二. 自给的电源如何工作 设计框图的自给的电源如图2所示。基本的工作原理如下:使用一个特殊的电流互感器诱导三相一侧的总线,然后信号通过整流电路处理。直流信号,输出整流器的电路,是输入信号的采样电路，在同一时间电容器也可以充电储能。带电电容器维持电压信号到一个特定的范围,然后电压信号进行降压和直流转换通过开关稳压集成电路。其输出是稳定的直流电压信号,为低压直流电源的电子电路提供保护装置。所面临的困难通过这种方法有:电容器的电压问题和稳定的输入电压的稳压集成电路。如果电容器的端电压超过它的额定电压电容器将损坏。当总线目前已在高电流状态,可能会导致过度的电容器充电从而导致损坏组件。本文设计了一个简单的电压比较器电路和MOSFET开关电路来整流电压信号从而电流得到范围限制。不仅保证了电容器的额定电压并且也获得一个稳定的电压输入对于调节器。图2 设计框图的自给的电源三、电流互感器的设计 一般保护电流互感器二次输出电流的值是5 a / 1 a,这是更大的取样电路。因此,在保护电流互感器和采样电路应用程序之间应该添加一个电流转换器,以达到当前的要求值。本文选取AMZ- 0.5模型电流互感器,二次输出电流是比平常小。所以,整流电路没有电流变换器,它能满足要求。 比较应用程序和各种性能指标不同的磁性材料,我们选择H9硅钢。这种材料具有较高的初始磁导率,可以减少起动电流,其饱和磁通密度值大,保证核心不饱和的一次侧电流情况下,损失的核心小,增加了能量转移效率。 根据上面的材料,气隙的核心增加到减少整个磁路磁阻和高性能核心材料被选中。此外,体积和重量的核心应该是最小化到可能的前提下,满足所需能源后端电路。硅的内部直径的选择钢芯d = 55毫米,外部直径d= 95毫米,高度h= 20毫米,饱和磁通密度Bs = 1.85 t,然后,平均磁路长度l =(d + D)/ 2 = 235.6毫米。如果长度的核心air-gap= 1毫米,然后相对磁导率的核心增加了差距相当于235.6 eq,磁导率是极大的减少了。在这一点上,励磁电流造成核心价值1436.7aA max、有效价值的电流1016A,这表明在使用这个结构核心不会饱和当线电流是在1016A。 事实上,为了解决气隙方便,两个0.5毫米厚非磁性材料垫在两个C型核心的中间。由于其相对磁导率为1,效果是一样的气隙。 在空载条件下，当当前有效导体I1=40A，为了获得二次线圈位9V的有效电压有： 在那里,U2是二次侧电压,f是电流频率、N2是二次侧线圈转动次数,Bm是磁通密度的振幅,Seq是有效的横截面积的磁心,是磁心层叠系数,U0是真空磁导率。式子是： 在这种情况下,核心结构和气隙长度的确定,正确的方程(2)等于一个常数。让这个设计值作为替代,1500 2 N(转)。选择钢心漆包线,载体密度计算根据8 A /平方毫米,线的横截面面积是0.667/8=0.083375平方毫米,对应于直径0.326米。考虑一定的利润,最后的选择是0.45毫米直径铜心线。四、一些关键技术A、信号采集和充电电路 三相交流电流信号,从初级侧总线通过电流互感器,首先通过控制桥式整流电路。交流信号改变为直流电流信号,然后通过电阻R转换为电压信号 .这个电压信号可以被用作输入的采样信号,也可以使电容器充电储能，单相桥式整流电路和控制电路如图2。所以它可以保证无论任何一阶段储能电容器充电整流器传导电流,是满足电力需求。图2 单相桥式整流电路和充电控制电路B、稳压电路 LM2576电压调节器用于电压调节器电路,图3所示。一系列开关调节器LM2576是一个单片集成电路,适合降压开关调节器,可以驱动3.0A的负载。其固定输出电压为3.3v,5.0v、12v,15v。功耗LM2576非常低,只要一个小尺寸附加散热就行。图3 稳压电路 LM2576的最大允许输入电压是40v,达到一个稳定的直流电压输出。在设计中调节器的输入电压VDD仅限于一定的电压通过MOSFET控制电路范围。然后开关调节器可以输出稳定的直流电源满足需要的通用电子电路。C、半导体场效应晶体管控制电路 为了防止电容器作为电容器端使电流信号继续充电，导致电压超过它额定电压,并且获得稳定的调节器的输入电压,本设计介绍了一个MOSFET控制开关电路。如图4所示框图。图4 MOSFET控制开关电路 滞回电压比较器电路比较参考电压VREF的调节器输入电压VDD和整流电路输出电压VEE。通过电路设计,当任何一个电压值高于参考电压,MOSFET将打开。这意味着整流电路输出电压VEE连接到零电位,充电过程的电容器停止;当电压值低于参考电压MOSFET的会关掉,VEE充电电容器。这样,输入的电压调整器保持在预设范围来满足调节器输出电压要求。此外,它还可以避免过度引起的损坏电容器充电。五、结论 电源使用的优点是电流互感器结构简单,成本低。因为高端的电子电路和光电设备较少,这些将不影响电能质量。这个电源模块可以被视为一个单独的装置;然而,困难在于在总线电流是缺乏情况下其动态范围是适应变化的。 电源设计在本文中使用一个特殊的电流变压器来从初级侧获得权力和专注于解决功率转换和功率传输的信号转换从电流互感器。设计一个自供电的电路,类似于开关电源,为数字继电器提供一个稳定的和可靠的电源。该方法可以避免饱和问题的核心圈通过增加气隙的核心线圈和引入气隙磁阻导致一次电流在一个更大的范围内改变。所以,后端电路得到大大简化，可靠性得到改进。 解决的电源采用了浮动电力,其中涉及到电流的大小,而不是电压水平。因此,电源模块可以用继电器在10千伏电压及以上级别电力系统保护和在线监测设备,具有广阔的应用前景。承诺书 本文支持关键科学问题和陕西省科技创新项目(编号:2009 zkc02-13)和国家基本理论研究项目(编号:2009cb724507-3)。参考文献1 Http:/. Digital self-powered Over-current RelayEB/OL. Schaltanlagen Elektronik Gerte GmbH & Co. KG,2004.2 QI Dong. “A Kind of Power Supply of Optic-electric Current TransformAccommodating Wide Bus Dynamic Current”. Proceedings of the CSEE，Vol.26, No.19: pp.160-164, 2007.3 Qian Zheng. “Power Supply for High Voltage Circuit of Active Electronic Current Transformer”. High Voltage Apparatus.， Vol.40,No.2：pp.135-138, 2004.4 Zhenquan Sun，Xuefeng Zhao，Hongwei Gu，Yanming Li. “A new design of power supply for electronic current or voltage transformer”.Proceedings of International Conference on Machine Learning and Cybernetics, 2009.7, B22:1-4.5 Wu Jintao, Sheng Gelai, Zeng Yi, Jiang Xiuchen. “Power supply designof monitoring device used in Transmission line on-line”. Power SupplyTechnology，No.2: pp.33-35, 2009. Kang Qiulan, Liu Shuguang, Li PengfeiSchool of Electronic and Information Eng.Xian Polytechnic UniversityXian, Chinakangqiulan2006Shi WenshengXian Yuanzheng Technology Co.Xian, China外文原文1：Design of Self-supplying Power Source Applied in Digital RelayAbstractAt present, the vast majority of relay protection devices depends on a reliable on-site power supply to work. Its power supply of work and operation circuits require substation or distribution room to provide AC or DC power supply. This paper introduces a design of self-supply power source applied in digital relay. The energy is obtained directly from the power line by some tailor-made iron core current transformer (CT). The signal, output of the rectifier circuit, is the input signal of sampling circuit and can also charge energy storage capacitor at the same time. An integrated switching regulator changes voltage signal, terminal of the energy storage capacitor, into stable DC voltage signal, as the DC regulated power supply of digital relay. The approach can avoid the saturation problem of core coil when primary current change in a larger range by increasing the air gap in the core coil and introducing air-gap magnetic reluctance. So that the back-end circuit is significantly simplified and the reliability is improved. The power supply module can be used in relay protection of power system with 10kV voltage level and above and on-line monitoring devices, which has a broad application prospects.Keywords-Self-supplying power source; iron core current transformer (CT); digital relay; air-gap reluctance; energy storage capacitorI. INTRODUCTION All along, the relay protection devices own power supply of work and operation circuits require substation or distribution room to provide AC or DC power supply. If there was no power at the scene, relay protection devices can not work. Can it be able to work without power supply like some of the RTU devices used in distribution automation? Can it be able to self-supply power from the high-voltage line? Currently, a class of device developed by the German SEG company appeared in the market, called digital self-powered over-current relay. Such devices do not need external power supply; power supply is directly obtained from TA installed in the high-voltage line. The conception, to take power from the TA as power supply unit of work loop and operation, is the innovation of self-powered digital relay. The appearance of the digital self-powered over-current relay show in Fig.1. Some researchers have raised a variety of power supply means, such as solar energy with lithium battery power, laser power, microwave power, and online access to energy use special TA, etc2-4. Of this total, the way of special TA installed in high-voltage side give online access to power electronic circuits is the most promising power supply. However, there are some issues to be solved about this power supply method, mainly including5: (1) How to ensure stable part of the voltage for electronic circuit when primary current (1) changes in a larger range(1%120%I). This is currently an urgent problem need to solve; (2)The stability problem of the approach to take power; (3) The issue of saturation of core coil. To solve these problems, this paper presents a power supply solution used in digital relays. The approach can avoid the saturation problem of core coil when primary current change in a larger range by increasing the air gap in the core coil and introducing air-gap magnetic reluctance. So that the back-end circuit is significantly simplified and the reliability is improved. Furthermore, lithium-ion battery pack is added in online access to power, which makes its power supply more reliable. There is no dead zone within 24 hours in the day, which makes the power supply module has been widely used.Figure 1 appearance of the digital self-powered over-current relay II. HOW SELF-SUPPLYING POWER SOURCE WORK Design block diagram of self-supplying power source shown in Fig.2. The basic working principle is as follows: use a special current transformer to induce three-phase current signals from primary side of the bus, and then the signal are processed through rectification circuit. The DC signal, output of the rectifier circuit, is the input signal of sampling circuit and can also charge energy storage capacitor at the same time.The charged capacitor maintain voltage signal to a certain range, and then the voltage signal is carried out step-down and DC transformation by switching integrated regulator. Its output is stable DC voltage signal, as low-voltage DC power supply of the electronic circuit protection devices. The difficulties faced by this approach are: the voltage pressure issue of capacitor and the stability of input voltage of integrated regulator.Capacitor will be damaged if end voltage of capacitor exceeds its rated voltage. When the bus current has been in a high current state, may cause excessive capacitor charge likely to cause damage to components. This paper designed a simple voltage comparator circuit and MOSFET switching circuit to limit the rectified voltage signal range. Not only ensures thecapacitors rated voltage but also obtains a stable voltage input for regulator.Figure 2 Design block diagram of self-supplying power sourceIII. DESIGN OF CURRENT TRANSFORMER The value of secondary output current of general protective current transformer is 5A/1A, which is larger for the sampling circuit. Therefore, a current converter should be added between the protective current transformer and the sampling circuit in application, in order to achieve the requirement of current value. This paper selects AMZ-0.5 model current transformer, the secondary output current of which is smaller than usual. So,it can satisfy the requirements of rectifier circuit withoutcurrent converter. Comparison of applications and all kinds of performance indicators of different magnetic materials, we have chosen H9 silicon steel. This material has high initial permeability, can minimize the starting current; its saturation magnetic flux density value is large, which can guarantee core unsaturated in a larger primary side current circumstances; the loss of core is small, increasing the efficiency of energy transfer. According to the materials above, the core air gap is increased to reduce the entire magnetic circuit reluctance and high-performance core material is selected. Furthermore, the volume and weight of core should be minimized as far as possible under the premise of meeting the power required by the back-end circuit. The internal diameter of selected silicon steel core d = 55mm, the external diameter D = 95mm, height h= 20mm, saturation magnetic flux density Bs=1.85T, then, the average magnetic circuit length l = (d + D) / 2 = 235.6mm . If the length of core air-gap =1mm , and then the relative magnetic permeability of the core increased the gap is equivalent to 235.6 eq , magnetic permeability is greatly reduced. At this point, excitation current value caused core saturation I 1436.7A max , effective value of current is 1016A, which shows that the core will not be saturated when the wire currents are within the 1016A after using this structure. In fact, in order to fix air gap conveniently, the two 0.5mm thick non-magnetic material is padded in the middle of two C-shaped core. Due to its relative permeability is about 1, the effect is the same as the air gap. In the no-load conditions, when the conductor effective current I1=40A, in order to obtain the 9V valid voltage from the secondary coil, there are: Where, U2 is the secondary side voltage, f is current frequency, N2 is the number of secondary side coil turns, Bm is the amplitude of magnetic flux density, Seq is the effective cross-sectional area of core, is core lamination factor, 0 is the vacuum magnetic permeability.Order was: In the circumstances that the core structure and the length of air gap are determined, the right of equation (2) is about equal to a constant. Take in the design value as substitution, 1500 2 N (turns). Select enameled wire with steel heart, carrier density is calculated according to 8A/mm2, the cross-sectional area of wire is demanded 0.667/8=0.083375mm2, corresponding to a diameter of 0.326mm. Take into account a certain margin, the final choice is wire with 0.45mm copperheart diameter.IV. SOME KEY TECHNOLOGIESA. Signal Acquisition and Charging Circuit The three-phase AC current signal, sensed from primary side bus by current transformer, first passes through the controlled bridge rectifier circuit. The AC signal is changed into DC current signal, which is then converted to voltage signal by the resistor R. This voltage signal can be used as the input of sampling signal, can also charge energy storagecapacitor. Single-phase controlled bridge rectifier circuit and charging circuit shown in Fig.2. The output of three-phase rectifier circuit are connected together in parallel, so it can guarantee that the energy storage capacitor is charged regardless any one phase rectifier conduction current on, that is to meet the power requirements.Figure 2 Single-phase controlled bridge rectifier circuit and charging circuitB. Voltage Regulator Circuit LM2576 voltage regulator is used in voltage regulator circuit, shown in Fig.3. Series of switching regulator LM2576 is a monolithic integrated circuit, suitable for step-down switching regulator, can drive 3.0A load. Its fixed-output voltage is 3.3V, 5.0V, 12V, 15V. Power consumption ofLM2576 is very low, only a small size additional heat sink is needed.Figure 3 Voltage Regulator circuit LM2576s maximum allowable input voltage is 40V, so as to achieve a stable DC voltage output. In the design, the regulator input voltage VDD is limited to a certain voltage range through the MOSFET control circuit. And then switching regulator can output stable DC power supply satisfied the need of general electronic circuits.C. MOSFET Control CircuitIn order to prevent the current signal from continuing to charge capa