The Study On A Full Temperature Range Calibrator For SF₆ Gas Density Relays

SF6 gas density relays are mainly used to monitor the gas density changes in SF6 insulated equipment in order to know the situation of the SF6 electrical equipment. SF6 density relays is an indispensable part of the SF6 circuit breaker and Gas Insulated Switchgear.Whose performances have a direct influence on the safety and reliability of the quipment. It is a necessary means for SF6 gas density relay periodic calibration to ensure the safe operation of SF6 electrical equipment, but the current density relay calibrator is used only under the normal conditions.The SF6 gas density relay is actually running at low or high temperature environments, only full temperature range calibration ensure SF6 gas density relay quality and the safe operation of grid.This paper presents the development of full temperature range calibration of SF6 gas density relays,and studies from the following three aspects.Firstly,this paper studies the principle and the conventional method of calibration of SF6 gas density relay.The software compensation and SF6 gas compensation method of calibration is put forward.This paper choose the best model of determined the relationship of pressure and temperature of SF6 gas.Secondly,this paper describes the designs of the main components of the calibrator.Including IPC, temperature control system, detection system, fully enclosed SF6 gas pressure regulation system,vacuum system,hardware circuits, software, and human-machine interface.Finally,performance tests demonstrate that this calibrator can fulfill the full temperature range calibration of SF6 gas density relays.Performance tests include pressure,temperature and temperature compensation error test.The necessity of full temperature range calibration of SF6 gas density relays is further verified by Using this calibration.