What’s the HVIL on new energy Vehicle?
High Voltage Inter-lock (HVIL for short), a safe design method for monitoring the integrity of high-voltage circuits with low-voltage signals. Theoretically, the low-voltage monitoring circuit is connected first and then disconnected than the high voltage, and the necessary advance is maintained in the middle. The length of time can be determined according to the specific situation of the project, such as 150ms, which is roughly in this order. Specific implementation forms of high-voltage interlocking may have different designs for different projects. The monitoring target is an electrical interface element such as a high-voltage connector that requires manual operation to achieve circuit on or off.
In the high-voltage circuit of electric vehicles, the electrical components that require HVIL function are mainly high-voltage connectors and manual maintenance switches (MSD).
High-voltage Inter Lock Principle
There are two aspects of the high-voltage interlock design that need to be considered. One is how the low-voltage system can comprehensively detect the connection status of each connection position of the entire high-voltage system. The other problem is how to achieve the information transmission action of the low-voltage detection circuit. Open circuit action. Therefore, the high-voltage interlocking principle needs to proceed from these two aspects, considering the overall circuit design principle and the connector design principle.
