Development Of Distributed On-Line Monitoring System For Substation Battery

Substation battery is not only an important part of UPS(uninterruptible power supply)system,power system DC power supply,and power communication power supply system,but also an indispensable independent backup power supply.If the operation status and health degree of the battery can not be mastered in time,the power supply capacity of the battery group can not be guaranteed.In case of power failure and other emergency situations,the power supply guarantee may not be provided according to the design time limit,which will cause the information communication interruption,dispatching unable to carry out real-time monitoring on the power grid,and even cause the protection equipment to malfunction or refuse to operate,and the whole power system will fall into a paralyzed state.Unnecessary casualties and property losses are caused in serious cases.Therefore,it is of great significance to monitor the status of battery in Substation in real time to ensure its safety and reliability.However,due to the large capacity,large base number and scattered placement of storage battery in substation,the operation efficiency of traditional battery inspection device is too low,and it is not conducive to the replacement and mobile operation of battery.To solve the above problems,combined with the battery inspection requirements of Guigang Power Supply Bureau substation,this paper proposes a distributed monitoring strategy of wireless ad hoc network,and develops the corresponding system device.Firstly,this paper analyzes the working principle,main technical parameters and monitoring methods of substation battery.The advantages and disadvantages of AC and DC testing methods for battery internal resistance are compared,and DC grouping instantaneous discharge method is determined to test battery internal resistance.Secondly,the battery model of substation is constructed and the SOC estimation method is studied.The software and hardware modular development of the system is completed.The hardware design includes control unit,voltage acquisition module,current acquisition module,temperature acquisition module,internal resistance acquisition module,wireless communication ad hoc network module,etc.the software design includes main program,monitoring subprogram and alarm program.Then,on this basis,the terminal architecture of network operation is designed.The monitoring data can be published on the internal website of the Bureau through the web page,realizing the remote management and real-time online monitoring of the battery.Finally,data intelligent analysis is introduced into online data monitoring and analysis.The collected voltage,internal resistance and other parameters were compared and analyzed combined with the check discharge test.It is used to judge the state of battery and its performance change.The operation test results show that the system can realize real-time on-line monitoring of the terminal voltage,single voltage,internal resistance,charging and discharging current,operating environment temperature and other operating parameters of the substation storage battery.At the same time,it can also be scientifically and effectively predicted the performance changes of the battery by using data resources,which has a good engineering application prospect and value.