Study And Application Of On-line Monitoring System At Transformer Substation

The oil field electric network has been adopting the traditional periodical downtime for maintenance ever since. This maintenance mode has many disadvantages: it was done under the condition that the power was off, and that the intenance was unscientific and not real-time and somewhat aimless; the power-off was too frequent and the test cycle was too long; it could not carry out tracing test on the insulation of running electric facilities; it could not figure out without delay the potential malfunction of the interior of the facilities; when power was off for predictive maintenance such as leaking, etc., the test voltage was much lower than the running voltage and the response for some defects was not so sensitive.In view of the above, the author suggested performing on-line insulationmonitoring at Weigang 110kV transformer substation of our oilfield. Theresearching subject of this thesis was to realize fully automatic on-line insulationmonitoring at Weigang transformer substation, to take real-time monitoring on theinsulation situation of this substation's coupling capacitor, main transformer, 110kVvoltage transformer, 110kV current transformer and arresters, to process theAfferent insulation parameters of each facility, to save data, alarm and transfer thedata distantly. Therefore, the author designed some parts of the hardware of thissystem, developed zero magnetic flow with high-resolution of sampling and superability of anti-jamming and bus cable controller, installed signal debug device, fixedground system and ground electrode that was isolated to the substation's groundsystem. Combined with the software of this system, this hardware system realizedthe on-line insulation monitoring data collection and transferring them by LAN.This thesis first introduced the current maintenance situation of the electric network facilities, analyzed the features and disadvantages of periodical downtime maintenance, and briefly introduced the developing situation of on-line monitoringof electric network facilities and its advances. In following, the paper showed the system illustration of the total design and introduced the signal collection part of this on-line monitoring system, including current transformer, bus cable controller. Then it came the signal debug device, protecting shield and power source, computer connection, signal process. At last, the paper presented the using situation of the on-line monitoring system and analyzed some important cases.