Patent ID: 11892495
Assignee: LS ELECTRIC CO., LTD.
Field: Measurement (Instruments)
Classification: CPC G | IPC G  H

Claim 14:
15. A method for controlling an insulation monitoring device comprising insulation resistance disposed between an electric line of a system and a ground, the method comprising:
applying a pulse signal having a voltage of a predetermined magnitude to the electric line;
determining an initial sampling interval;
performing primary tuning of calculating a sampling interval based on the initial sampling interval and a first time multiple, calculate an average voltage as a first average voltage during a sampling period according to the calculated sampling interval, and comparing the calculated first average voltage and a second average voltage calculated before the first average voltage;
detecting whether a difference between the first average voltage and the second average voltage is within a preset first error range as a result of the primary tuning;
terminating the primary tuning and performing secondary tuning of calculating a sampling interval based on a preset sampling interval and a second time multiple, calculating an average voltage as a third average voltage during a sampling period according to the calculated sampling interval, and comparing the calculated third average voltage and a fourth average voltage calculated before the third average voltage;
detecting whether a difference between the third average voltage and the fourth average voltage is within a steady voltage error range as a result of the secondary tuning;
detecting whether a predetermined time has elapsed from a starting time point of the secondary tuning when the difference between the third average voltage and the fourth average voltage is within the steady voltage error range, to detect the third average voltage as a steady-state voltage according to the applied pulse signal when the predetermined time has elapsed; and
repeatedly performing the secondary tuning when the difference between the third average voltage and the fourth average voltage exceeds the steady voltage error range as a result of the secondary tuning or when a predetermined time has not elapsed from the starting time point of the secondary tuning.