Mitsubishi electric corporation (20240297496). Restricted Earth Fault Relay simplified abstract

Restricted Earth Fault Relay

Organization Name

mitsubishi electric corporation

Inventor(s)

Reiji Watase of Chiyoda-ku, Tokyo (JP)

Shigeto Oda of Chiyoda-ku, Tokyo (JP)

Restricted Earth Fault Relay - A simplified explanation of the abstract

This abstract first appeared for US patent application 20240297496 titled 'Restricted Earth Fault Relay

The abstract describes a restricted earth fault relay that includes a first differential amount calculation unit, a current change detection unit, a first suppression amount calculation unit, and an operation determination unit.

• The first differential amount calculation unit calculates a first differential amount based on a zero-phase current and a neutral point current.
• The current change detection unit detects changes in the phase currents.
• The first suppression amount calculation unit calculates a first suppression amount when changes in the phase currents are detected.
• The operation determination unit outputs a protection signal for protecting a three-phase transformer when the first differential amount and the first suppression amount are within an operating region.

Potential Applications: - Protection of three-phase transformers in electrical systems. - Monitoring and detecting earth faults in power distribution networks.

Problems Solved: - Ensures timely protection of transformers against earth faults. - Enhances the reliability and safety of electrical systems.

Benefits: - Prevents damage to transformers and other equipment. - Minimizes downtime and maintenance costs in electrical systems.

Commercial Applications: Title: "Advanced Earth Fault Relay for Transformer Protection" This technology can be used in industrial plants, power substations, and utility companies to safeguard critical equipment and ensure uninterrupted power supply.

Questions about the technology: 1. How does the first suppression amount calculation unit determine the first maximum value? 2. What are the key advantages of using a restricted earth fault relay in electrical systems?

Original Abstract Submitted

a restricted earth fault relay includes: a first differential amount calculation unit that calculates a first differential amount based on a zero-phase current and a neutral point current; a current change detection unit that detects changes in the phase currents; and a first suppression amount calculation unit that calculates a first suppression amount. when the changes in the phase currents are detected, the first suppression amount calculation unit calculates a first maximum value as the first suppression amount, the first maximum value being a maximum value of effective values of the subtraction currents in the phases and an effective value of the neutral point current. the restricted earth fault relay further includes an operation determination unit that outputs a protection signal for protecting a three-phase transformer, when the first differential amount and the first suppression amount are within an operating region.