Fault Diagnosis And Fault Tolerant Control Of Joint Actuator Of Transmission Line Robot

With its high efficiency and high quality,live working robot has become the main force of live working in power transmission lines in China.During the operation,the failure of the robot’s joint driver will lead to the degradation of joint flexibility,which may lead to joint locking,and the robot will be forced to go offine for maintenance.In order to improve the reliability of the robot,the fault diagnosis and fault-tolerant control method of the joint actuator of the transmission line live working robot based on the particularity of the working environment and the field application are studied in this thesis.First of all,the failure mechanism of the actuator of the live working robot on the transmission line is analyzed.Based on the discussion of the failure mode of the robot.the failure mechanism of the actuator is analyzed from three aspects:the weakening of the electromagnetic protection by the slot in the case,the electromagnetic environment and the transient process of the equipotential process.The failure mechanism of the live working robot is discussed.Based on the detailed analysis of the three-phase stator current variation when the power tube is in open circuit fault,a power tube open circuit fault diagnosis method based on the current distortion characteristics is proposed.According to the different values of distortion factors F1x and F2x when the power tube is in fault,the fault diagnosis and location of the power tube is realized.This method is suitable for the fault diagnosis and location of power tube under different rotating speeds and different loads of robot joint motor,and is not affected by the change of working conditions.Then,taking the live line maintenance robot of transmission line damper as an example,on account of the D-H representation method,the kinematics of the live line operation robot is analyzed,the forward kinematics equation and the inverse kinematics equation are solved,and the change of the working space of the robot under the condition of single joint fault is analyzed.According to the inclusion relationship between the target pose and the degraded working space under the fault of single joint driver,the path planning strategy based on the random road sign graph and the fault tolerance strategy based on the redundancy of joint driver are proposed.On the basis of numerical simulation of robot fault-tolerant path planning strategy with stochastic road map method,the hardware and software of the fault-tolerant system are designed.In this thesis,the fault diagnosis algorithm of drive power tube is verified by the joint motor drive system model based on Simulink and the expansion joint drive system platform of transmission line damper maintenance robot;Based on the main control system of STM32F407 robot and the upper computer platform of QT,the fault tolerance strategy is implemented in the control program.The fault-tolerant control experiment of live working on 110 kV line in Hunan Electric Power Company of State Grid is carried out,and the validity of the proposed fault-tolerant method is verified.