Traversing In-Core Probe Drive Unit and Method for Monitoring Friction of Inside of Guide Tubes

Abstract

A TIP drive unit that calculates a cable drive torque stably is provided. In accordance with the invention, Traversing In-core Probe (TIP) drive unit includes a housing, a storage reel configured to storage the probe cable, a drive mechanism including a motor, and configured to feed the probe cable form the storage reel and spool the probe cable onto the storage reel, a motor controller configured to drive the motor at a predefined rotating speed, a processor configured to calculate a cable drive torque that is a torque necessary for moving the TIP and the probe cable by using a value of supply power necessary for driving the motor, a value of the predefined rotating speed of the motor, and a loss torque that is a torque necessary for driving the drive mechanism, and a noise filter configured to remove noise included in a signal indicating the value of the supply power.

1 . A Traversing In-core Probe (TIP) drive unit for moving a TIP connected to an edge of a probe cable in a guide tubes,
 comprising:
 a housing having an introduction path; 
 a storage reel provided in the housing, and configured to storage the probe cable; 
 a drive mechanism provided in the housing, including a motor, and configured to feed the probe cable from the storage reel and spool the probe cable onto the storage reel through the introduction path; 
 a motor controller configured to supply a supply power to the motor, and drive the motor at a predefined rotating speed; 
 a processor configured to calculate a cable drive torque for moving the TIP and the probe cable in the guide tubes by using
 the supply power for driving the motor by the motor controller, 
 the predefined rotating speed of the motor, and 
 a loss torque for driving the drive mechanism; and 
 
 a noise filter configured to remove noise included in a signal indicating the supply power. 
   
     
     
         2 . The TIP drive unit of  claim 1 ,
 wherein the motor controller includes an inverter configured to drive the motor, and   wherein the noise filter is a low-pass filter configured to remove high-frequency noise generated by the inverter.   
     
     
         3 . The TIP drive unit of  claim 1 ,
 wherein the motor controller includes an inverter configured to drive the motor, and   wherein the noise filter is a low-pass filter configured to remove higher frequency noise than power-supply frequency of the inverter.   
     
     
         4 . The TIP drive unit of  claims 2  and  3 ,
 wherein the inverter has a larger electric capacity than necessary for an usual flux measurement. 
 
     
     
         5 . The TIP drive unit of  claim 1 ,
 wherein the motor controller is configured to drive the motor at a various speed, and   wherein the processor configured to calculate the cable drive torque by using the loss-torque depending on the various rotating speed.   
     
     
         6 . The TIP drive unit of  claim 4 ,
 wherein the motor controller is configured to move the TIP at high-speed in the guide tube and move the TIP at low-speed in the calibration tube.   
     
     
         7 . The TIP drive unit of  claim 1 ,
 further comprising:   a function configured to homologize the cable drive torque and a position of the TIP and the probe cable where the cable drive torque was measured.   
     
     
         8 . The TIP drive unit of  claim 1 ,
 wherein the processor is configured to compare the cable drive torque and a normal cable drive torque, and determine the position where a lubricant fell away in the guide tube.   
     
     
         9 . A method for monitoring friction of inside of guide tubes, comprising:
 moving a TIP and a probe cable by a drive mechanism including a motor in the guide tubes;   measuring a value of supply power necessary for driving the motor and a value of the predefined rotating speed of the motor;   calculating a cable drive torque that is a torque necessary for moving the TIP and the probe cable in the guide tubes by using
 the supply power for driving the motor, 
 the predefined rotating speed of the motor, and 
 a loss torque for driving the drive mechanism; and 
   removing a noise included in a signal indicating the supply power.