Research On Operation And Maintenance Management Of Substation DC Power System

The function of the DC power supply system in the substation is to provide working power for the protection and closing mechanism after the loss of AC power supply in the station,and to ensure that the fault loop can be detached from the power grid system to avoid the substation blackout accident.However,because of the backward maintenance methods,the lack of staff bearing capacity and the lack of more perfect monitoring and maintenance methods,the DC power supply system in substation has potential security risk.Recent years,the substation accident caused by the abnormal work of DC power supply system occurred.In the operation and maintenance management of the substation DC power supply system,it still relies on the traditional "manual,equipment,experience" semiautomatic production and management mode,which has some problems such as lack of information collection,difficult state evaluation and trouble warning.In order to solve the above problems,Therefore,it is necessary to study a new monitoring and management platform based on the properties of the dc system equipment and the current maintenance mode.In this paper,the design scheme of dc power supply operation and maintenance management system is proposed and verified on site.The work done in this paper is as follows:(1)analyze the operation status of dc power system;(2)Describe the principle and method of insulation monitoring of battery bank operation and DC system;(3)Complete the hardware and software.STM32F407ZGT6 is used as the control chip to complete the design of the circuit such as voltage,internal resistance,current and temperature detection,wireless communication,bus voltage detection,feeder current detection and power supply for the series battery unit.In order to ensure the reliability and expansibility of the system,ISO 124 isolated operational amplifier circuit and Hall current sensor are designed to complete isolated sampling of battery,bus voltage,battery and feeder current signals.MLX90615 non-contact infrared temperature sensor is designed to complete the temperature detection of the battery pack.CD4051 switching circuit is designed to complete the voltage data acquisition of multiple single cells.The information interaction between the detection device and the LIQUID crystal display screen is designed through wireless communication.In Keil development environment to complete the development of system software,to cosII as the operating system,complete the design of the module program.Realize the detection of the battery's voltage,current,internal resistance and temperature,realize the detection of bus voltage and feeder current,and realize the rapid disposal of abnormal hidden danger of DC power system according to the detection data.Through the comprehensive monitoring of the running data of substation DC power supply system,each module of the DC system can be monitored effectively,and the state evaluation model of the DC power supply system can be established through comprehensive analysis,which can correctly evaluate the running state of the DC power supply and provide security for the safe operation of the substation.