INTELLIGENT CIRCUIT BREAKERS WITH AIR-GAP AND SOLID-STATE SWITCHES

• Main Authors: Alton, Kenneth D, Gerber, Stephen C, Baker, Damon M, Telefus, Mark
• Format: Patent
• Language: English
• Published: 19.11.2020
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SWITCHES; ELECTRICITY; EMERGENCY PROTECTIVE DEVICES; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; RELAYS; SELECTORS; TESTING

A circuit breaker comprises a solid-state switch, an air-gap electromagnetic switch, switch control circuitry, a zero-crossing detection circuit, and a current sensor. The solid-state and air-gap switches are connected in series in an electrical path between line input and load output terminals of the circuit breaker. The switch control circuitry controls the solid-state and air-gap switches. The zero-crossing detection circuit detects zero crossings of an AC power waveform on the electrical path. The current sensor senses current flow in the electrical path to detect a fault condition based on the sensed current flow. In response to a detected fault condition, the switch control circuitry generates control signals to place the solid-state switch into a switched-off state and place the air-gap switch into a switched-open state after the solid-state switch is placed into the switched-off state. The switch control circuitry utilizes zero-crossing detection signals output from the zero-crossing detection circuit to determine when to place the air-gap switch into the switched-open state.