Device used for detecting direct current power supply connected to alternating current power supply and direct current power supply ripples and used in transformer substation

Abstract

The invention discloses a device used for detecting a direct current power supply connected to an alternating current power supply and direct current power supply ripples and used in a transformer substation. The device comprises a transformer substation direct current bus, a working power module (15), an alternating current voltage sampling circuit (3), a band-pass filtering circuit (4), a direct current voltage sampling circuit (8), a filter circuit (9), a ripple voltage sampling circuit (10) and the like. A CPU module (6) is connected with a voltage analog-digital conversion circuit (5), a direct current voltage analog-digital conversion circuit (10), a ripple voltage analog-digital conversion module (13), an alarm uploading communication interface (16), a display screen (7), a man-machine interaction keyboard (11) and an alarm output circuit (14) respectively. The device is used for quickly detecting whether the alternating current power supply is connected to the direct current power supply and giving an alarm in time when detecting an abnormity; the device also can be used for on-line monitoring of ripples of a direct current system charging unit, thereby being capable of greatly improving the reliability of the direct current power supply and safe operation of a power grid.

Description

Technical field: [0001] The invention relates to an alternating current power supply used in a substation and a direct current power supply and a ripple detection device for the direct current power supply, and belongs to the technical field of power system substation maintenance. Background technique: [0002] 1. The DC system used in the substation is an indirect grounding system. When the DC power supply is mixed with the AC power supply, it will cause the DC system to be grounded, which may cause the protection to refuse to operate or malfunction, thereby inducing serious accidents. State Grid Corporation of China's "Eighteen Major Power Grid Anti-Accident Measures of State Grid Corporation" (revised version) "5.1.1.18.3 clearly stipulates: Newly built or renovated substations, DC system insulation monitoring devices should have AC channeling DC faults Measuring and alarming functions. The current DC insulation monitoring devices do not have the measuring and alarming fu...

AI Technical Summary

Problems solved by technology

The existing charging and floating charging devices do not meet the above requirements, and the detection of the ripple coefficient of the DC power charging device requires live work, which is dangerous and cumbersome.

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