摘要：The Objective of this paper is to give more insight into CCM Operation of the LCL Converter to obtain op-timum design using state-space analysis and to verify the results using PSPICE Simulation for wide variation in loading conditions. LCL Resonant Full Bridge Converter (RFB) is a new, high performance DC-DC con-verter. High frequency dc-dc resonant converters are widely used in many space and radar power supplies owing to their small size and lightweight. The limitations of two element resonant topologies can be over-come by adding a third reactive element termed as modified series resonant converter (SRC). A three ele-ment resonant converter capable of driving voltage type load with load independent operation is presented. We have used embedded based triggering circuit and the embedded ‘C’ Program is checked in Keil Software and also triggering circuit is simulated in PSPICE Software. To compare the simulated results with hardware results and designed resonant converter is 200W and the switching frequency is 50 KHz.

摘要：This paper presents and tests three earthing systems (TT, TN and IT) for Micro-Grid (MG) protection against various fault types when the MG transferred to the islanding mode. The main contribution of this work is including the models of all micro sources which interfaced to the MG by power electronic inverters. Inverters in turns are provided with current limiters and this also included with the inverter models to exactly simulate the real situation in the MG during fault times. Results proved that the most suitable earthing system for MG protection during the islanding mode is the TN earthing system. That system leads to a suitable amount of fault current sufficient to activate over current pro-tection relays. With using TN earthing system, touch voltages at the faulted bus and all other consumer’s buses are less than the safety limited values during islanding mode. For the two others earthing systems (TT and IT), fault currents are small and nearly equal to the over load currents which make over current protection relay can not differentiate between fault currents and overload currents. All models of micro sources, earthing systems, inverters and control schemes are built using Matlab?/Simulink? environment.

摘要：Since in designing the full adder circuits, full adders have been generally taken into account, so as in this paper it has been attempted to represent a full adder cell with a significant efficiency of power, speed and leakage current levels. For this objective, a comparison between five full adder circuits has been provided. Applying floating gate technology and refresh circuits in the full adder cell lead to the reduction of leakage current on the gate node. The simulations were accomplished in this paper, through HSPICE software and 65 nm CMOS technology. The simulation results indicate the considerable efficiency of power consumption, speed and leakage current in the full adder cell rather than other cells.

摘要：A new class of compact and lightweight S-band 1 kW traveling-wave tube (TWT) is being developed for a microwave power module (MPM) that will be used for phased antenna array radar applications. The proposed S-band MPM provides a tenfold peak power increase compared to state-of-the-art S-band MPMs. In this paper, the design of the vacuum power booster TWT part of the MPM is presented. The compact and lightweight S-band TWT is driven by a 6 kV, 0.9 A electron beam. The amplifier is predicted by large-signal simulations to generate over 1 kW at S-band with 25 dB saturated gain and over 40% efficiency. The stability from unwanted oscillations has been investigated. To suppress the oscillations, the helix circuit has been coated with carbon composite material. The coaxial input and output antennas have been fabricated. For efficiency enhancement, a multi-stage depressed collector (MDC) has been designed using a 3D particle-in-cell (PIC) simulator, VORPAL. The collector design makes use of a current loop based on a feedback mechanism for effective design process. The integrated designs of a helix circuit, an electron gun, a periodic permanent magnet (PPM), antennas, and a collector are presented.

摘要：In this paper, the impact of extra electron source(EES) and dual metal gate engineering on conventional charge plasma TFET(CP-TFET) have been done for improving DC and analog/RF parameters. CP-TFET structure is upgraded to double source CP-TFET(DS-CP-TFET) by placing an EES below the source/channel junction for enhancing the device performance in terms of driving current and RF figures of merit(FOMs). But, in spite of these pros, the approach is having cons of higher leakage current similar to MOSFET and negative conductance(inherent nature of TFET). Both the issues have been resolved in the double source dual gate CP-TFET(DS-DG-CP-TFET) by gate workfunction engineering and drain underlapping respectively. Additionally,for getting the optimum performance of DS-DG-CP-TFET, the device sensitivity has been investigated in terms of position of EES,length of drain electrode and workfunction of gate electrode 1(GE1).

摘要：The mathematics and physics model of OCT (Optical current Transformer) with a gapped magnetic ring is briefly discussed in the paper. And some proposals of how to select the magnetic materials and crystals and reduce the stress birefringence of the crystal are also put forward in the paper. Based on the above, an OCT with 1000 A rated current is designed by using the ANSOFT Maxwell tools.

摘要：针对电力系统3种调度模式对直流电网实时的潮流分布要求,在多端柔性直流输电(voltage source converter multiterminal direct current,VSC-MTDC)系统中设计了相应的协调控制策略,通过改变下垂系数的值和切换控制模式,以满足直流电网中的潮流分布。为避免控制模式的频繁切换,在受端换流站控制器中加入了滞环比较器。通过在PSCAD/EMTDC仿真软件中搭建的四端柔性直流输电系统,对直流电网处在不同的调度模式下分别进行仿真,结果表明,与定下垂系数的控制方式相比,该协调控制策略可以满足电力系统调度对潮流实时的分布要求,直流电网的输电灵活性得到提高。

摘要：With the rapid development of digital signal processing chip in recent years, DSP began to be used in more switching power supply. The advantages of digital control of their own, making the digital control PFC become a hotspot research. However, compared with the simulation system, the digital control technology still has many problems. In this paper, the problem of digital PI compensator as a voltage compensator is discussed, and the Single-pole voltage loop compensator is used in digital control PFC circuit. Because current loop bandwidth is narrow, a method to expand current loop bandwidth is put forward. Output power 300 W of prototype is made, and experimental results verify the correctness of the theory.

摘要：提出了一种利用转子位置传感器发出的信号测量无刷直流电机(BLDC)转速的方法,并设计了相应的转动方向测定电路和数字PI速度控制器模块。通过利用比例积分控制器计算半个转动周期内的两次连续测量值,结合提出的转动方向测定电路和数字PI速度控制器,可以得出具有双倍测量频率的转子转动周期的准确值。最后将提出的方法在FPGA平台进行了实现,并与真实数据的对比表明,该算法在无换向器直流电机上可以获得具有高精度及高速度频次的测速度。

摘要：介绍了防止金属管道电化学腐蚀的阴极保护原理和方法,并针对电气化铁路、电车和以接地为回路的输电系统,产生的杂散电流,阐述了避免地下管道电化学腐蚀的防护措施。