CB like battery disconnect switch sys replace fuse and contactor in EVs
Date: 30/05/2022
In abnormal situation to cut the electric current flowing into the battery or sourcing from the battery, electric vehicles need a battery disconnecting switch solution, so that the batteries are fully isolated from the rest of the vehicle electrically. Abnormal situations include fire hazards, accidents, vehicle misuse, unsafe batteries, natural disasters, drive system failure and also ADAS failures. You need a switch to disable or enable battery connection in your electric car/vehicle. The switch need to be dynamic so that it can be enabled or disabled easily with least physical action and not replacing any components such as fuse.
The leading power electronic maker Eaton has made available an active battery disconnect unit (BDU) by using its circuit protection technology called Breaktor replacing passive fuse and contactor. Resettable like a Circuit Breaker (CB), this breaktor device takes less than 4 milisecond actuation for short circuit faults up to 900 volts and 25,000 amps. Breaktor limits current in the event of a short circuit in both directions.
The BDU offers a bidirectional resettable short-circuit protection and current switching with fast actuation, replacing combination of thermal fuses and contactors. This on/off like switch connects battery to the charging unit and traction.
The benefits of BDU includes both active and passive actuation in a single device, switching off based on fault conditions. The most important advantage is its ability to reset after a fault detection without replacing any components.
“Our Breaktor circuit protection technology’s self-triggering design, diagnostic electronics and mirror contact help achieve BDU functional safety goals,” Calzada said. “With its integrated coil driver, economizer, and the sensing/triggering circuit, Breaktor circuit protection technology also reduces battery management-system cost and complexity.”
“Breaktor achieves best-in-class current ratings, and these can be even further increased with an appropriate cooling strategy,” Calzada said. “Eaton is able to design and develop a compatible cooling system to customer specifications and integrated into a BDU to meet these rising power requirements.”
The other features include Integrated pre-charge circuit, Up to 350kW DC fast charge circuit, Low voltage connectors, Isolation detection available, Current and voltage sensing available and current sensor monitored by battery management system.
To know more on this BDU visit: https://www.eaton.com/us/en-us/catalog/emobility/battery-disconnect-unit.html
To learn more on the breaktor visit:
https://www.eaton.com/content/dam/eaton/products/emobility/power-distribution-protection/breaktor/eaton-breaktor-brochure-emob0002-en.pdf
Author: Srinivasa Reddy N
