Analysis on dynamic characteristics of voltage - frequency converter circuit 电压一频率转换电路的动态特性分析及求解
A protective method based on voltage - frequency - converter and additional dc measuring the insulation between monitor wire and ground lines of hv double screen cable is developed and realized by analog and digital circuits 通过分析6kv电缆绝缘监视保护的特点,提出了在高压电缆监视线与接地线之间附加直流电源并利用v / f转换实现监视保护的新方法,设计了相应的电路。
According to the test conditions , the double polarity inputting mode is adopted in the circuit of voltage - frequency converting part ; storage batteries are used in the optical emission part of optical fibre isolating and transmitting device , that can guarantee isolation between the main circuit and the testing system ; the 89c51 singlechip is used in the singlechip testing - controlling unit , the peripheral circuits are extended , data are transmitted through the serial port in this part ; the p opular software delphi5 . 0 is used in the pc part , the communication between singlechip and pc by serial port , plotting of current wave , regulation of data ; the optical - electrical isolating and triggering are used in the controlling part , this can guarantee the veracity and reliability of breakers triggered , this triggering mode is also used in the triggering of the main closing breaker , the tested breaker and the assistant breaker , the triggering signals are sent out by a singlechip 压频转换部分电路中根据实际情况采用了双极性输入方式;光纤隔离传输装置的光发射部分电源采用了蓄电池供电,确保了主回路与测试回路的完全隔离;单片机测控部分采用了89c51单片机,扩充了外围电路,通过串口向pc机传送数据; pc机与单片机之间的串口通讯、波形绘制、数据管理等都采用了软件delphi5 . 0编写。该测试系统中预留了输出口,可以对合成回路中的主合闸开关、被试开关、辅助开关进行触发,信号由单片机发出,控制部分采用了光电耦合隔离触发的方法。软件设计主要集中在对电流信号的数据采集、数据处理、数据传送、人机界面、波形绘制和数据管理,软件部分又可分为单片机和pc机程序设计两大部分。
The whole large current testing system based on voltage - frequency converting technique has been finished in this paper , and the dc voltage signals , power frequency ac voltage signals are tested by this computer - testing system , the results are good , then the current of current - source in the synthetic circuit are tested by this computer - testing system 本文完成了一整套基于压频转换技术的大电流测试系统,首先测量了直流电压信号、工频交流电压信号,然后完成了对合成回路中电流源电流信号的测试。
In the computer - testing system of current signal measurement of current - source in synthetic circuit , the following contents are included , such as voltage - frequency converting technique , optical fibre isolating and transmitting technique , singlechip testing and controlling , plotting and printing of sampled data on pc ( personal computer ) 电流源电流信号的计算机测试系统包括传感元件部分、压频转换部分、光纤隔离传输部分、单片机测控部分以及pc机对采集数据的波形绘制与打印部分。