Fatigue test method of compound insulator based on electric-hydraulic proportional-servo loading technology and iterative learning control

In order to simulate the vibrating condition in breeze and carry out the fatigue test for the compound insulator, the electro-hydraulic loading technology for the compound insulator is researched. Based on actual loading characteristic of the compound insulator, a compound electro-hydraulic servo load system is firstly designed, including static proportional load and dynamic servo load sub-systems. Then the working principle of this system is analyzed, and the mathematic model of electro-hydraulic servo load is also built. The control method based on PD-type iterative learning control is designed, to achieve the high-precision control for dynamic load force. The mathematic simulation based on AMESim and Matlab is completed. The results of simulation and actual experiment have proved that the load principle and control method are correct and feasible, and can achieve high-precision control effect. According this discussed electro-hydraulic loading technology and control method, the actual electric-hydraulic loading system for compound insulators has been developed, with 150 kN maximum static force, 20 kN maximum dynamic force, 0.3 kN force control precision and 100 Hz maximum load frequency, and more than 30 million number of continues vibration.