Design and implementation of remote power safety measurement and control system

　　1 Introduction

　　An electric energy production and consumption system composed of power generation, transmission, transformation, distribution and consumption. Its function is to convert primary energy in nature into electrical energy through power generation devices, and then supply the electrical energy to various users through power transmission, transformation and distribution. In order to realize this function, the power system also has corresponding information and control systems at various links and different levels to measure, regulate, control, protect, communicate and dispatch the electric energy production process to ensure that users receive safe, economical and high-quality services. of electrical energy. In recent years, my country's power system has developed rapidly, and many substations and power supply stations are undergoing automation and unattended transformation. Therefore, it has become necessary to apply condition monitoring and control technology and develop new condition monitoring and control technology in power systems such as substations. It is one of the most important tasks in the research of my country's power integrated automation system.

　　Control technology is an advanced strategy and novel technology in modern control theory. Fuzzy control technology is based on fuzzy mathematical theory and improves the controllability, adaptability and rationality of the control algorithm by simulating human approximate reasoning and comprehensive decision-making processes, becoming an important branch of intelligent control technology. The major of computer control technology is to train students to master certain electronic and electrical knowledge, computer operation application knowledge, programming knowledge, have certain professional knowledge of computer control technology, computer network technology, programmable control technology, etc., and have strong analytical ability and hands-on ability. Competence, innovation ability, high-quality compound and application-oriented professional and technical talents who can solve practical engineering problems 3. Edit entry Network control technology

　　2 System architecture design

　　This system is mainly composed of two modules: the main control module and the remote control module.

　　2.1 Remote control module

　　The remote control module includes a radio frequency transceiver and a remote control processing chip AT89C51. Their connection methods are the same; in order to facilitate users to view the voltage value of high-voltage wires in real time and set new reference voltages, etc., we add an LCD1602 liquid crystal display and a The 4×4 matrix keyboard is connected to the P0 port and P3 port of AT89C51 respectively. Its hardware structure diagram is shown in Figure 1.

　　Figure 1 Remote control module hardware structure diagram

　　2.2 Main control module

　　In the main control module part, the A/D digital-to-analog conversion sub-block is connected to the voltage sensor module and receives the analog signal from the voltage sensor; the P2 port of the main control chip AT89C51 is connected to the analog high-voltage switch module and sends out high and low levels for control The closed state of the switch circuit and its main control module hardware structure diagram are shown in Figure 2.

　　Figure 2 Main control module hardware structure diagram

　　3 Software system implementation

　　On the basis of the hardware structure, the corresponding software must be designed to exert its due effect. The software system is mainly composed of system initialization module, startup self-test module, main control module, data acquisition module and various interrupt service program modules. The following focuses on the main control program design method. The main control program of the software system is a cycle program. The main control module part mainly consists of the main control program (see Figure 3), interrupt program, analog switch control program, radio frequency transceiver program, etc.

　　3.1 Main control module process

　　Figure 3 Main control module program flow chart

　　The relevant main control module programs are as follows:

　　#include 《reg52.h》

　　#include 《ABSACC.h》

　　#include 《intrins.h》

　　#include 《STdio.h》

　　#define uint unsigned int

　　#define uchar unsigned char

　　void main（ ）

　　{

　　void delay(uint z); //delay function

　　void Init(); //Initialization function

　　while(1) //Give an infinite loop and keep sampling

　　{ //Receive interrupt

　　AD= Read_ADC(); //Get voltage data from AD converter

　　ADCON &= ~0x10; //Clear ADCON.4 (ADCI) to start a new conversion

　　Send(AD); //Send the current analog circuit voltage back to the remote control display

　　Delay(5000); //delay 5 milliseconds

　　ES=0; //Turn off serial port reception

　　If (auto=1) //Determine whether the analog switch control is manual or automatic

　　{

　　If (AD《=v1-v2 || AD》=v2+v2) //Comparison of the circuit voltage value obtained from AD and the reference value

　　{

　　Switch=1; //When the AD value is far from the reference value, that is, high voltage or low voltage failure, the analog circuit will be turned off.

　　Delay(10000); //Delay 10 milliseconds

　　}

　　}

　　ES=1; //Open serial port to receive

　　}

　　3.2 Remote control module process

　　Figure 4 Remote control module program flow chart

　　The remote control program (see Figure 4) corresponds to the functions of the main control module. It transmits control commands to the main control module through the wireless duplex protocol, and then transmits the measured voltage value back to the remote control through the wireless network, and then displays the measured voltage value. .

　　4 Summary

　　This system makes a brief and practical improvement to the power switch control of some current high-voltage power systems and solves related problems. It only cuts off and closes the measured abnormal voltage, and lacks a stable circuit for the current abnormal voltage. Since this system adopts the design concept of modularization and interface and the communication mode of wireless network, it is very convenient to change the hardware and transplant the software.