特高压试验示范工程已成功投入商业运行。由于电压等级高、设备相对复杂，为了及时掌握设备运行健康水平，避免一次设备损坏，特高压变电站主要一次设备均加装了在线监测系统。介绍了现场系统构成，并结合现场运行实例总结了在线监测系统的运行经验。

The demonstration project of UHV AC transmission, with high voltage level and relatively complicated equipments, has been put into commercial operation, where the online monitoring systems are applied to the preliminary main equipments in order to understand the operation state of equipments and avoid the failure of preliminary equipments. The construction of the system is introduced, and the operation experiences are summarized based on the practical application.