Optimal Placement of Health Monitoring Sensor for Bridge Structure of Air-Cooled Island

Abstract

The air-cooled island of air-cooled thermal power unit consists of dozens of cooling units with fans and their bridges. Its structure and excitation load are complex. The health status of the air-cooled island has an impact on the safe operation of thermal power unit. In this paper, an optimal placement of health monitoring sensor for bridge structure of air-cooled island is proposed based on effective independence method. Through the finite element analysis, the main mode shapes of the bridge structure were obtained. Based on this, a given number of sensors were optimally arranged according to the Fisher information matrix. Then the optimal placement of the health monitoring sensor for the bridge structure of air-cooled island was obtained. The modal guarantee criterion was used to evaluate the placement scheme. The result shows that the sensor placement scheme can ensure the accuracy of modal identification and effectively reflect the structural characteristics of the bridge structure of the air-cooled island. The result can provide a reference for the health monitoring of the bridge structure of air-cooled island.