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

Claim 5:
6. 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;
calculating a sampling interval according to the determined initial sampling interval, calculating an average voltage during a sampling period according to the calculated sampling interval, and calculating an average voltage during a sampling period according to a sampling interval updated according to a first time multiple;
detecting whether a difference between a currently calculated first average voltage and a second average voltage measured before the first average voltage is within a preset first error range;
identifying the first average voltage as a steady-state voltage according to the applied pulse signal or updating the sampling interval by applying a different time multiple according to the difference between the first average voltage and the second average voltage, as a result of the detection;
repeatedly performing those steps of calculating the average voltage during the sampling period according to the updated sampling interval, detecting whether the difference between the voltages is within the preset first error range until the steady-state voltage is identified, and updating the sampling interval by applying the different time multiple;
detecting whether there is a steady-state voltage according to a pre-identified another type of pulse signal when the steady-state voltage is identified;
identifying the steady-state voltage according to the another type of pulse signal by inverting the pulse signal to the pre-identified another type of pulse signal and re-performing the determination of the initial sampling interval and the repeatedly performing step when the pre-identified another type of pulse signal is present as a result of detecting whether there is the steady-state voltage according to the pre-identified another type of pulse signal; and
calculating a value of the insulation resistance based on steady-state voltages according to different types of pulse signals when the pre-identified another type of pulse signal is present as a result of the detection of the step of detecting whether there is the steady-state voltage according to the pre-identified another type of pulse signal.