电路

In order to solve the problems of bad shunting and red light strip phenomenon at electric railway section caused by the defective of asymmetric pulse track circuit receiver formerly, a new type of asymmetric impulse track circuit receiver is designed. It takes the PIC16F887 single-chip microcomputer as central processing unit of the system, realizes processing and judging the asymmetric impulse from the track transformer automatically. The article focused on the receiver work flow, hardware circuit and software design.

摘 要：为了解决以往多数不对称脉冲轨道电路接收器存在缺陷而导致的分路不良问题和电气化区段空闲&红光带&现象，设计了一种新型脉冲轨道电路接收器，系统以PIC16F887单片机为核心处理单元，自动实现对由轨道变压器传来的不对称脉冲信号进行处理和判决，重点讨论了接收器工作流程、硬件电路实现以及软件设计。

There is a mounting hole on the bottom of the shell, Anion generating circuits packed together with carbon fiber bundle forms the anionic pulse generator which is inserted into the mounting hole and placed in the middle of the lamp shell.

负离子节能灯，包括灯头、灯壳、灯管、灯电路、负离子发生电路及碳纤维束，灯壳底座设有安装孔，负离自发生电路与碳纤维束封装于一体组成负离子发生器—整体插合于安装孔并置于灯壳外灯管中间。

Firstly, the realizable ways of signal detection and sample、 power circuit and the application of low-consumption model of MSP430 are discussed, by which the required function of current protection and voltage protection can be realized. Secondly, different protection algorithm based on micro-computer are discussed in this article, and from the virtues and defects of Fourier algorithm, an improved algorithm is put forward, and the importance of the improved algorithm is displaced. Thirdly, according to the national standard of GB/T18858 .3-2002, the principle of networklization of intelligence trip relay and how to realize it are mentioned. Lastly, using the current conditions, the test of precision is done. The experimental date present that the system is working well and can realize the real-time function of on-line detection.

首先在硬件设计上，对于信号检测、处理、电源电路、MSP430系列单片机的低功耗方式应用以及人机接口电路等问题提出了实现方法，基本实现了大范围电流、电压信号实时监控等功能；其次，本文还对当前各种微机保护算法进行了介绍，分析了傅立叶算法在实现智能脱扣器保护功能中的优缺点，并针对傅立叶算法中计算偏于复杂的问题对该算法进行了改进，提出了基于FFT的改进算法，通过算法的分析和比较，对改进算法的性能给出了评价；然后结合我国现场总线国家标准GB/T18858.3-2002讨论了DeviceNet现场总线在实现脱扣器网络化的原理，实现方法，论述了通讯接口电路的设计；最后利用现有条件，对装置进行了性能测试，试验数据说明系统工作状态较好，可以满足低压配电网自动化对低压脱扣器的各项要求。

Secondly, whole-chip ESD protection net is put forward. Input protection circuits, output protection circuits and circuits between high-voltage ground and low-voltage ground are decided on the base of structure and process of PDP drive chip. Moreover, the design of low-voltage VDD-to-VSS ESD protection circuits is detailed and the circuit is simulated with HSpice. Finally, the characteristic of high-voltage device after avalanche breakdown is simulated and analyzed with Tuprem-4 and MEDICI, and it is concluded that high-voltage device can stand high voltage and large current, so the low-voltage VDD-to-VSS ESD protection circuits can be applied to high-voltage VDD-to-VSS ESD protection.

随后提出PDP驱动芯片全芯片ESD保护网络的方案，并根据PDP驱动芯片的结构和制造工艺，介绍了输入部分、输出部分及高低压接口部分的ESD保护电路，然后重点分析了低压电源和地之间ESD保护电路的设计并用Hspice进行了模拟，最后使用Tuprem-4和MEDICI模拟了高压器件在雪崩击穿之后的电压电流和电场分布特性，得出高压器件本身可以承受一定的ESD脉冲，从而将低压电源和地之间的ESD保护电路应用到高压电源和地之间。

The hardware circuit mainly includes master controller,temperature measurement circuit and display circuit.

介绍了一种以AT89C51为主要控制器件，以DS18B20为温度传感器的新型数字温度计设计方法，其硬件电路包括主控制器，测温电路和显示电路等。

A connection is designed via the NMOS switch to combine together the two circuits all via the concept of multiple-pass such that a wider range of oscillation frequency can be obtained.

然后再利用 NMOS 作为开关电路，将加快振荡频率的多重路径振荡器电路与减慢振荡频率的多重路径振荡器电路结合在一起。

Abstracts: To sample high speed random signals without drop, a design of O-shaped high speed random signals acquisition card based on the CPLD and its realization are presented. It consists of same three sets of acquisitive circuits, which construct O-shaped structure to sample the signals without drop .And it adopts threshold judging method to determine the valid data in the process of the acquisition, abandons vast of the redundant useless data at the same time, it only sends the useful data to the host computer by the way of DMA, so it is easy to processing the data. The design is concise and reliable. The sketch map of the logic circuit and the explanation of the main parts are presented. This design has been applied in the engineering project of sampling α nuclide.

为了对随机到来的信号进行不丢失的高速采集，提出了一种基于CPLD的随机信号环形高速采集卡的设计与实现；通过采用三套采集电路形成一个环形结构，可以对随机到来的信号进行不遗漏的高速采集，而且在采集过程中利用阈值的方法鉴别出有用信号，并舍弃了大量的冗余无用数据，从而只将有用数据以DMA的方式传于主机，便于进行信号的处理；电路设计简洁可靠，并给出了主要的逻辑电路示意图与主要部件说明；该系统已经应用在采集α核素的工程实践中。

The voltage converted into 0～5 V using convering circuit can be used directly by microprocessor ,and con2 verted into digital signals by A/ D converting. So this simplifies the design of the circuits.

通过电压转换电路可以将- 10～+ 10 V 的输出电压转变成为0～5V 的电压，便于带有A/ D 转化电路的单片机系统直接进行A/ D 转换，简化了电路设计。

A new three-phase AC voltage-regulating AC circuit which use thyristor three-phase bridge controlled rectifier as three-phase symmetrical Y connection is presented.

提出了一种用晶闸管三相全控整流电路用作三相Y接对称性电阻性负载进行的三相交流调压电路，此调压电路由晶闸管三相全控整流电路改造而成，并分析了工作原理，给出了实验结果。

The transmitter changes the voltage signal of the sampling resistance into an optic pulse signal by neon tube, and then the optic pulse signal is changed into an electrical pulse signal and transmitted to the receiver by the optical fiber transmission system.

发射电路通过氖管把取样电阻取得的电压信号变为光脉冲信号，光脉冲信号经光纤传输系统转换为电脉冲信号传输到接收电路，接收电路对电脉冲信号进行测量。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐