CN1091532C

CN1091532C - Telemechanical terminal

Info

Publication number: CN1091532C
Application number: CN97119961A
Authority: CN
Inventors: 陈晓林
Original assignee: CHANGLIN ELECTRONIC AUTOMATIC CONTROL EQUIPMENT Co Ltd BAODING CITY
Current assignee: CHANGLIN ELECTRONIC AUTOMATIC CONTROL EQUIPMENT Co Ltd BAODING CITY
Priority date: 1997-10-30
Filing date: 1997-10-30
Publication date: 2002-09-25
Anticipated expiration: 2017-10-30
Also published as: CN1182919A

Abstract

The present invention relates to a remote terminal of an automatic key apparatus for dispatching electric power, which is composed of a computer and function modules. The present invention is characterized in that an alternating current sampling transmitter is utilized, so the accuracy of measurement results is improved, and the periodical regulation of the sampling transmitter is avoided. Buses of single chip microcomputers AT89C52 and I<2>C are utilized on a remote signalling module and a remote control module in the terminal, so the terminal has the advantages of simple circuit and good anti-interference capacity; a Pentium computer is used as a host, so the terminal also has the advantages of good processing function, good real-time performance and friendly human-machine interface. Each module is provided with an integrated circuit MAX705 and a microcomputer monitoring circuit, the circuits can automatically start after the circuits are electrified so as to operate each real-time monitoring program, and the circuits can automatically reset and start again. The remote terminal can store data of remote measurement and remote signalling for a long time, and data can be stored for 10 years.

Description

A kind of remote terminal unit

The present invention relates to power industry dispatching automation equipment, particularly a kind of remote terminal unit.

Remote terminal unit is to be used for transformer station and generating plant to gather remote measurement, remote signals, realizes the automation equipment of remote control and teletransmission.The remote terminal unit of existing domestic production is divided into two kinds: a kind of is traditional direct current sample mode, and this mode needs 2 racks, and the precision instability, uses loose mail too much; Another kind is the AC sampling computer transmitter, uses a rack, and integrated level is higher than the direct current sampling, and precision is relatively stable.But because old type tubes such as its microcomputer chip uses 8051,8098, peripheral configuring chip is more, and speed is low, and figure place 8 is few, and precision is low.And, adopt the sync section of AC sampling all to use phase-locked loop circuit, this circuit adopts the electric capacity vibration, when temperature variation is big, occur step-out easily, and phase lock circuitry is the hardware self-adapting frequency multiplication, low-frequency oscillation is arranged, in one-period, can not strictly divide cycle equally, stability, reliability is relatively poor.Therefore, the still difficult demand that satisfies power industry.

Purpose of the present invention will provide exactly that a kind of integrated level height, anti-interference are strong, precision is high, installation and maintenance are easy, is applicable to the remote terminal unit of power scheduling department and farmland department.

For finishing the remote terminal unit that the invention task designs, cable and rack by computing machine, telemetry module, remote signal module, remote control module, channel module, mutual inductor module, power module and connection computing machine and each module are formed, and its computing machine is the Pentium computer of band intelligent multi-serial-port card of expansion and Windows3.2 Chinesizing version; The mutual inductor module comprises voltage transformer pt summation current transformer CT; Telemetry module is by the signal of card extender tandem mutual inductor module converts output, integrated circuit MAX307 in it, enter the A/D converter AD7874 that include four road sample/hold amplifiers, 12 A/D converters, fifo buffer, 12 bus outputs, mail to Pentium computer after handling by cpu chip 80C196KC again; Remote signal module is in the impulse electric charge module I to be arranged ²C bus interface integrated circuit PCF8574.Gather remote signalling or pulse signal, and connect pin 1, the pin 2 of single-chip microcomputer AT89C52, after software was handled signal filtering, serial port mail to Pentium computer with remote signalling state and counted number of pulses; The single chip computer AT 89C52 of remote control module receives the guidance command that Pentium transmits, and delivers to I ²C bus interface integrated circuit PCF8574 from integrated circuit PCF8574 readback data again, is sent to Pentium computer then, and carries out the order that Pentium computer passes down, makes the relay executable operations; And channel module also uses single chip computer AT 89C52, and with pulse signal after filtering and amplify driving, export terminal row to.

Extendible 2 at most of telemetry modules among the present invention make the collection circuit reach 64, and the voltage hop count reaches 16; And configurable 2 of remote signal module, each remote signal module has 8 integrated circuit PCF8574, can gather 64 remote signalling or pulse signal; Channel module also can connect 2, receives function to realize one two.

Remote terminal unit of the present invention adopts the AC sampling computer transmitter, has removed to cut hardware circuits such as phase-locked loop circuit that existing type uses, memory, capacitance resistance ware, and measurement result precision height has been removed the work of regular adjustment transmitter from; Its remote signalling, remote control module are owing to adopt single chip computer AT 89C52 and I ²The C bus, thus circuit is succinct, good in anti-interference performance; Because adopt 586 computer to make main frame, processing capacity is strong, uses C Programming with Pascal Language under the Windows, and is real-time, the man-computer interface close friend; This equipment is powering up back startup automatically, operation real-time monitor (RTM) separately; This terminal can be stored remote measurement, remote signalling data for a long time, and remote measurement was deposited once in per 5 minutes, and remote signalling each minute deposits once, and the data-storing capacity was 10 years.If behind spread F AX card, video card and camera on the Pentium computer, also transformer station's image can be reached dispatching terminal by telephone wire.

Below in conjunction with accompanying drawing the present invention is described.

Fig. 1 is a remote terminal unit block diagram of the present invention.

Fig. 2 is the telemetry module electrical schematic diagram of remote terminal unit of the present invention.

Fig. 3 is the remote signal module electrical schematic diagram of remote terminal unit of the present invention.

Fig. 4 is the channel module electrical schematic diagram of remote terminal unit of the present invention.

Fig. 5 is the remote control module electrical schematic diagram of remote terminal unit of the present invention.

As shown in Figure 1, remote terminal unit of the present invention is by computing machine, and the cable of telemetry module, remote signal module, channel module, mutual inductor module, power module and connection computing machine and each module is formed.Its principle of work is: the voltage transformer pt in the mutual inductor module will exchange 100 volts of voltage transitions for exchanging 5 vor signals.And current transformer CT will exchange to be converted to Ampere currents and exchange 5 vor signals.By the signal of plurality of voltages mutual inductor PT summation current transformer CT conversion output, after the change-over panel tandem, be forwarded to as shown in Figure 2 remote measurement template by shielded cable.Integrated circuit MAX307 (two eight select a multi-way switch) through in this module enters A/D converter AD7874, and this chip includes four road sample/hold amplifiers, 12 A/D converters, fifo buffer, 12 buses are exported.The travelling speed of its cpu chip 80C196KC is three times of 8098 chips.Include 512 byte RAM, set up peripheral hardware transaction processor PTS, can adopt the 16M crystal oscillator, the high speed input (HSI) of chip 80C196KC detects the 50Hz power frequency period, be divided into time of 96 by software and deliver to the high speed output (HSO) of chip 80C196KC, when arriving a time point, export (HSO) at a high speed and export a pulse enable A/D converter automatically, cpu chip detects A/D converter and converts signal, take out data, phase modulation order according to design, disposal data calculates then and adds up.When 96 gathered after, make average and extracting operation by software, mail to Pentium computer by serial port.The telemetry module maximum can be gathered 32 line currents, the data of 8 sections voltages, and every circuit can be surveyed electric current, voltage, active power, reactive power, phase place, power factor, and integrable active energy and reactive energy.And receive the phase modulation alphabetic data that Pentium computer transmits at any time.Extendible 2 at most of telemetry modules make the collection circuit reach 64, and the voltage hop count reaches 16.Remote signalling and impulse electric charge signal are to reach as shown in Figure 3 remote signal module through terminal strip by flat cable.Signal enters hardware anti-interference, isolation and low-pass filter circuit by switch earlier, enters I at last ²C bus interface integrated circuit PCF8574.Each remote signal module has 8 integrated circuit PCF8574, can gather 64 remote signalling or pulse signal.Integrated circuit PCF8574 gathers remote signalling or pulse signal, is connected to pin 1, the pin 2 of single chip computer AT 89C52 through its pin 14,15.Single chip computer AT 89C52 reads the input state of 8 integrated circuit PCF8574 by its

1,2 two I/O lines of pin, after by software signal filtering being handled, carrying out SOE judges and step-by-step counting, by serial port remote signalling state and counted number of pulses are mail to Pentium computer, and receive at any time that Pentium computer transmits to clock signal.This remote signal module had both been measured 64 status signals, had counted 64 pulse signals again.According to configurable 2 remote signal modules of request for utilization.Remote control module as shown in Figure 4, its single chip computer AT 89C52 receives the guidance command that Pentium computer transmits, and delivers to I ²C Bus Interface Chip PCF8574, then from integrated circuit PCF8574 readback data again, be sent to Pentium computer, Pentium computer is with the result of state contrast, mail to scheduling by channel module, after scheduling was confirmed to carry out, Pentium computer was with fill order, under reach the remote control module output password, make the output relay work in the relay module.Power supply output makes corresponding relay work, executable operations.Time-delay is set by software switch.During this period, the single chip computer AT 89C52 of remote control module ceaselessly detects the delivery outlet state, judges whether correct.This remote control module can drive closing of 32 circuits at most and divide.As shown in Figure 5, channel module has also used single chip computer AT 89C52, utilizes its T2,16 bit timing counters, and 0.1 signal becomes the pulse signal of 2850Hz and 3150Hz respectively, after filtering and amplifying driving, exports terminal row to.The detuner part of channel module adopts two frequency discriminations method of difference again, and 2850Hz and 3150Hz signal are reduced to 0 and 1.Remote terminal unit can connect 2 channel modules, realizes that one two is received function.If, transformer station's image is reached background computer and online chief's computing machine by multimedia technology.Behind Pentium computer expansion FAX card, video card and the camera with remote terminal unit of the present invention, can transformer station's image be reached background computer and online chief's computing machine more directly by telephone wire and the networking of backstage dispatching.

Claims

1, a kind of remote terminal unit, cable and rack by computing machine, telemetry module, remote signal module, remote control module, channel module, mutual inductor module, power module, relay module and connection computing machine and each module are formed, and it is characterized in that said computing machine is the Pentium computer of band intelligent multi-serial-port card of expansion and Windows3.2 Chinesizing version; The mutual inductor module comprises voltage transformer pt summation current transformer CT; Telemetry module is by the signal of card extender tandem mutual inductor module converts output, integrated circuit MAX307 in it, enter and include four road sample/hold amplifiers, 12 A/D converters, the A/D converter AD7874 of fifo buffer, 12 bus outputs mails to Pentium computer after the cpu chip 80C196KC processing by telemetry module again; Remote signal module is in the impulse electric charge module I to be arranged ²C bus interface integrated circuit PCF8574, gather remote signalling or pulse signal, through its pin 14,15 and connect pin 1, the pin 2 of single-chip microcomputer AT89C52, after software was handled signal filtering, serial port mail to Pentium computer with remote signalling state and counted number of pulses; The single chip computer AT 89C52 of remote control module receives the guidance command of Pentium computer, delivers to I ²C bus interface integrated circuit PCF8574 from integrated circuit PCF8574 readback data again, is sent to Pentium computer then, and carries out the order that Pentium computer passes down, makes the relay executable operations; Channel module also uses single chip computer AT 89C52, and with pulse signal after filtering and amplify driving, export terminal row to.

2, remote terminal unit according to claim 1 is characterized in that extendible 2 of said telemetry module, configurable 2 of remote signal module, and each remote signal module has 8 integrated circuit PCF8574, and passage mould poplar also can connect two.