A low-frequency insulation detection device and method for a power supply system

Abstract

The invention discloses a power supply system low-frequency insulation detection device and a method. The device comprises a first resistor, a second resistor, a measuring resistor, a low-pass filter unit, a pulse signal source, and a detection and calculation unit. The first resistor and the second resistor are connected in series with each other, and then connected in parallel with a detected power supply system. After the measuring resistor, the low-pass filter unit and the pulse signal source are connected in series, one end is connected between the first resistor and the second resistor, and the other end is connected with the ground. The detection and calculation unit is connected in parallel to the two ends of the measuring resistor. The pulse signal source emits a pulse signal, which passes through the measuring resistor, the low-pass filter unit, the first resistor and the second resistor, and is then injected to the detected power supply system. The detection and calculation unit calculates the insulation resistance of the detected power supply system to the ground by detecting the signal across the two ends of the measuring resistor, and judges whether the detected power supply system has an insulation fault according to the insulation resistance. The technical problem that the existing detection method takes a long time in measurement, is easily interfered, and is prone to false alarm in bad environments is solved.

Description

technical field [0001] The present invention relates to the field of electrical detection, in particular to a low-frequency insulation detection device and method applied to power systems, especially marine frequency converter systems, and the present invention can also be applied to other IT (that is, neutral point is not grounded) power supply systems . Background technique [0002] In the marine industry, frequency converters occupy an increasingly important position as a power supply system. Since the working environment of the ship is generally harsh, the impact of the deterioration of the climate on the equipment is particularly obvious, and the insulation failure rate of the power supply system is relatively high, so the rapid alarm of the insulation failure will be related to the safety of the entire voyage of the ship. [0003] At present, most marine power grids use IT (that is, the neutral point is not grounded) power supply system to improve the security of powe...

AI Technical Summary

Problems solved by technology

[0008] In view of this, the object of the present invention is to provide a low-frequency insulation detection device and method for a power supply system, which solves the technical problems that the existing detection method takes a long time to measure, is easily disturbed, and is prone to false alarms in harsh environments.

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