Research Based On The Acoustic Emission Of Wind Power Tower Drum Dynamic Monitoring Technology

Wind power generation technology has become increasingly mature, which occupies an important position in the field of renewable green energy development and has great potential value. People should pay attention to safety and quality of wind power generation when the wind power brings convenience. A single wind power equipment is very expensive, through the domestic several collapse cases can be seen that damage of the wind power equipment will cause huge economic losses to the enterprises although it will not cause casualties.Acoustic emission technology is a new type of dynamic nondestructive testing technology, which can represent the nature of physical phenomena in real time. It has been widely used in nondestructive testing field of industrial equipment. Compared with conventional NDT methods such as ultrasonic, magnetic powder, ray, permeability, acoustic emission is more sensitive to active defects, it can be for the overall monitoring in a test for structure, also it has advantages of short inspection cycle and high efficiency, etc. Forced deformation, phase transformation, crystallization of solidification, the motion of dislocation, crack generation and propagation of the metal material are accompanied by the elastic energy release, all of those events can produce acoustic emission signals, So we can monitoring and judge the integrity and security of the structure through analyzing the received acoustic emission signals. Integrated collapse of wind turbines currently and the characteristics of acoustic emission testing, the acoustic emission technique is applied to wind power tower drum on-line dynamic monitoring, detecting and evaluating the existence of active defects in the whole structure.On the basis of broad access to domestic and foreign literature of science and technology, this paper summarizes the basic principle and application status of acoustic emission technology. Based on tensile test and bending test of wind power tower drum material Q345E steel, it was studied under the tensile and bending load of damage and fracture behavior, discussed its acoustic emission signal characteristics of the crack propagation and fracture in the process of tensile and bending, gave the damage types and acoustic emission characteristics of each stage, discussed the acoustic emission technique can be used for the feasibility of wind power tower drum dynamic monitoring, the results show that the acoustic emission signal can well represent the tensile fracture and bending process of Q345E steel, provides basic data for the dynamic monitoring for reference.Through testing the wind power drum in the field, obtained the typical acoustic emission characteristics of acoustic emission source at the bottom of the barrel bolt joint in the working process, and by conducting re-inspection by magnetic memory technology, the result shows that acoustic emission technique can accurately positioning the dynamic defects of tower drum, which further demonstrates the feasibility of the acoustic emission technology using in the tower drum dynamic safety monitoring. The first test results also provide basic data for further testing. Acoustic emission technology in the application of wind power tower drum dynamic monitoring is still in its infancy, we are lack of understanding of the acoustic emission source in the field. Therefore, studying the acoustic emission source characteristic of the wind power tower in service and seeking effective acoustic emission source identification method in the detection are both urgent to solve, and they are premises to develop wind power tower drum acoustic emission detection standards and conduct on-site inspection.