Devices for active overvoltage protection

Abstract

The invention relates to a device for active overvoltage protection, and specifically discloses a circuit protection device. The circuit protection device includes an active energy absorber coupled between two power lines in an electrical distribution system and configured to selectively conduct a fault current in response to an overvoltage condition. The active energy absorber includes: an overvoltage protection module including two thyristors connected in antiparallel to each other; and a varistor connected in series with the overvoltage protection module. The series circuit including the varistor and the overvoltage protection module is connected between the power lines.

Description

technical field [0001] The present invention relates to circuit protection devices, and more particularly to overvoltage protection devices and methods. Background technique [0002] Excess voltage or current is often imposed across service lines that deliver electrical power to residential and commercial and industrial facilities. For example, such excessive voltage or current spikes (transient overvoltages and inrush currents) can be caused by lightning strikes. Facilities that are particularly affected by the events described above are telecommunications dispatch centers, hospitals, and other facilities where equipment damage from overvoltage and / or current surges and resulting downtime can be very costly. [0003] Typically, a surge protective device (SPD) is used to protect sensitive electronic equipment from transient overvoltages and surge currents. For example, simply refer to figure 1 , figure 1 is a system that includes conventional overvoltage and surge protec...

AI Technical Summary

Problems solved by technology

[0007] As provided above, means for protecting equipment from excess voltage or current spikes (transient overvoltage and surge current) may include products such as energy absorbers, which may be based on varistors, including for example metal oxide Varistors (MOVs) and / or silicon carbide varistors, and the energy absorber may not have a safe end-of-life mode of operation

Additionally, such devices may not provide protection at voltage levels approaching the operating voltage of the device

Further, SPD designs may not provide protection at voltage levels near the nominal system voltage and may not be designed to absorb as much energy as an energy absorber

Combinations of varistors and thyristors may not have a safe failure mode and will not protect against surge currents and transient overvoltages without an external SPD

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