Device and method for insulation monitoring in a power supply system including a high-resistance grounded neutral point

US10126345B2 · kind B2 · utility

Assignee

• Bender GmbH & Co. KG · DE

Inventors

• Dieter Hackl · Albach, DE
• Eckhard Broeckmann · Gießen, DE
• Burkhard Macht · Hungen, DE

Key dates

• Filing date: Dec 12, 2014
• Grant date: Nov 13, 2018
• Expiry date: Jul 6, 2035

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R31/14
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A device and method is for insulation monitoring in a power supply system composed of a main system including a neutral point that is high-resistance grounded via a neutral-point resistance and, optionally, of at least one subsystem, wherein the main system and the subsystem each have a differential current measuring device for registering a differential current.The invention is based on feeding a measuring signal into the optionally branched HRG system via an active measuring method and registering the fault current driven by the measuring signal in the outgoing power feeds to be monitored by means of a differential current measurement and using the registered fault current in an evaluating device to determine the total insulation resistance of the power supply system and to determine the partial insulation resistances of the main system and potentially present subsystems. Furthermore, the insulation monitoring device can be employed for insulation fault location.