A grounding detection method for converter control motor of converter oxygen lance

Abstract

The invention discloses a converter oxygen lance frequency converter control motor grounding detection method. The grounding detection method comprises the following steps: a speed encoder detects anactual operation speed of a converter oxygen lance frequency converter control motor and sends the actual operation speed to a frequency converter; the frequency converter compares the actual operation speed with a given speed set by a controller; and a resistance detector detects whether the resistance value of a winding of the converter oxygen lance frequency converter control motor is smaller than or equal to 0.5 Kohm. Through arrangement of the speed detector and the resistance detector, which are used for detecting the actual operation speed and the resistance value of the converter oxygen lance frequency converter control motor respectively, and through judgment of whether the speed difference value between the actual operation speed and the given speed is larger than or equal to 3HZ, whether the duration time when the speed difference value is larger than or equal to 3HZ is larger than or equal to 0.5 s, or / and whether the resistance value detected by the resistance detector issmaller than or equal to 0.5 Kohm, whether the converter oxygen lance frequency converter control motor has unidirectional grounding is determined, and lance drop accident can be prevented.

Description

technical field [0001] The invention relates to the technical field of steelmaking converter technology in the metallurgical industry, in particular to a grounding detection method for a converter control motor of a converter oxygen lance. Background technique [0002] The steelmaking converter oxygen lance control system is controlled by AFE Siemens frequency converter, which belongs to the three-phase ungrounded system. When the oxygen lance motor winding is grounded during the operation of the oxygen lance, the voltage of the motor line remains unchanged and the current does not increase significantly, so that the inverter cannot distinguish the single-phase grounding of the oxygen lance motor winding. At this time, the oxygen lance It can continue to run, but no matter whether the operation instruction is to lift or lower the gun at this time, the actual action of the oxygen gun is to lower the gun. Therefore, it is easy to cause the hidden danger of the gun falling acci...

AI Technical Summary

Problems solved by technology

[0003] This application provides a grounding detection method for the motor controlled by the frequency converter of the converter oxygen lance, which solves the problem in the prior art that it is impossible to judge whether the winding of the oxygen lance motor is grounded in one direction, causing the oxygen lance to continue to run, thereby causing the hidden danger of the gun falling accident, causing the motor Technical problems of two-phase or even three-phase winding burnout

Images