- General principles of high-voltage power-on and power-off response of each control node
The high-voltage power-on and power-off responses of each control node include a normal situation response and an abnormal situation response. The response action of each control node to the high-voltage power-on and off demand shall conform to the following general principles:
(1) Undesirable acceleration, deceleration, reversing and steering of the vehicle should be avoided or prevented.
(2) Personal casualties, equipment damage or environmental damage caused by high-voltage faults should be avoided or prevented.
(3) Meet the high-voltage power-on and power-off performance requirements.
(4) The performance requirements should be met on the premise of meeting the safety requirements, that is, the principle response priority of a and b should be higher than that of c;
- Principles of Response to Abnormal Situations
For any abnormal situation, there should be corresponding handling measures:
(1) If each control node has a response function corresponding to this abnormal situation and the function is normal, the response shall be performed according to the established function.
(2) If each control node has a response function corresponding to this abnormal situation but this function fails, it should consider adding the corresponding fail-safe function and respond according to the fail-safe procedure.
(3) If each control node has no feasible response plan for this abnormal situation, it shall take identification and explanatory measures for the residual danger.
(4) In the event of a vehicle accident, emergency high-voltage power-off should be performed.
(5) If Category I and Category II undesired personnel actions and vehicle high voltage faults occur at the same time, priority shall be given to dealing with vehicle high voltage faults. Unexpected personnel actions of Category III should be treated with emergency high-voltage power-off.
- Principles of Response to Undesired Human Actions
(1) For category I undesired human actions, if the vehicle has no fault, respond according to the Quick Key Cycle processing logic table shown in Table 1. Description: The vehicle speed condition is to consider that after the high-voltage power-on is completed, if the vehicle is still in a stationary state, it is considered that the current driver’s “driving” intention is still unclear, and the system should be in the original count state of Quick Key Cycle; if the vehicle starts to run, then Considering that the current driver’s “driving” intention is clear, the system should jump out of the original counting state of Quick Key Cycle, and the counter should re-count.
(2) For category II undesired human actions, because the actual driving intention cannot be judged, it is assumed that the driver has taken an abnormal operation under special circumstances, so each control node should respond according to the normal high-voltage power-off sequence.
(3) Emergency response to high-voltage power-off should be made for the undesired actions of Class III personnel.
- Response principles for vehicle high voltage fault conditions
When a high-voltage fault occurs in the vehicle, the high-voltage power-on and power-off response of each control node must meet the following principles:
(1) A high-voltage fault occurs in the vehicle during the normal high-voltage power-on process. If the fault is serious but the emergency high-voltage power-off conditions are not met, the power-on behavior should be stopped immediately and the motor should not be able to output (torque, electric energy), or DC/DC. There is power output, and the power-off is completed according to the normal power-off sequence.
(2) If a high-voltage fault occurs during the normal high-voltage power-off process, only the fault code is allowed to be recorded, and no response is made to the fault, and the power-off is completed according to the normal high-voltage power-off sequence.
(3) If the vehicle has a high voltage fault in any state (except the state that has entered or completed the high voltage power-off process), if the severity of the fault meets the conditions for emergency high-voltage power-off, each control node shall respond to emergency high-voltage power-off.
(4) For a fault that triggers an emergency high-voltage power-off, if the severity of the fault meets the condition that high-voltage power-on is not allowed, the vehicle is not allowed to be powered on again until the fault is manually eliminated.
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