From October 25th to October 26th, 2019, the China Bodywork Conference and Anxing China Leaders Summit was held in Macau. Autoliv, as the current rotating chairman, was invited to attend the summit. At the meeting, Autoliv put forward a solution for the safety problem of new energy vehicles, starting from a new generation of “power-off safety protection switch”.
Safety Challenges of New Energy Vehicles
At present, my country’s new energy vehicle production and sales have ranked first in the world for four consecutive years, and gradually entered the “overtaking lane” of new energy development. However, the frequent incidents of new energy vehicle fires in the past two years have brought its battery safety issues to the forefront.
In order to meet consumers’ requirements for cruising range and charging speed, in the case of limited battery system space, companies mostly increase the voltage and current by squeezing the battery density. In the event of a collision, the risk of current overload will be more likely to occur. Therefore, new energy vehicles Battery protection becomes critical.
Current power failure safety protection scheme
The key to automobile current overload protection is to cut off the short-circuit power supply in the shortest time, so as to prevent the high current from damaging the circuit components and causing the components to overheat and catch fire.
At present, most new energy vehicles in the market use high-voltage relays and high-voltage fuses (fuses) to prevent the risk of fire caused by overloading of circuit circuits. When the current is within a certain range, the on-off of the circuit can be controlled by the relay; only when the fault current is relatively high, the fuse starts to work, and the circuit current is cut off by fusing the body.
When the current is higher than the working range of the relay, but has not yet reached the fuse energy or the response time is long, it is enough to damage the circuit components such as the relay and cause high temperature fire. For the gray area that fuses and relays cannot meet, the market urgently needs new solutions.
The new power-off safety protection switch promotes the safety upgrade of new energy vehicles
Different from the fuse that needs a certain current value to trigger its action, the trigger signal of the power-off safety switch (PSS) can come from either the collision control unit or the BMS. After receiving the signal, the power output will be cut off within 1 millisecond, to prevent fire from the root cause, and reduce or eliminate the harm caused by vehicle fire to the occupants and surrounding areas.
The power-off safety switch (PSS) series, as an exclusive technology, has a number of technical patents. It can complete power-off protection within one thousandth of a second, which is much superior to similar products in sensitivity, and is not easy to age with time. Durable . In addition, different models of PSS can also meet different power models, such as PSS4 and PSS5, which are specially designed for new energy vehicles, and can also be used to protect the safety of charging stations.
Facing the rapid changes in the automobile industry, Autoliv adheres to the vision of “saving more lives”, and will continue to deepen the cooperation with Anxing China while continuously improving the level of automobile safety technology to adapt to the new development trend. Many people have popularized the concept of safe travel, and look forward to the realization of a “zero casualty” road safety environment in the future.