1) The hydrogen produced when power battery
charging through electrified wire netting It should be
ensured that the concentration of hydrogen could not reach
the flammable critical point when power battery charging
through electrified wire netting. It should be measured that
the concentration hydrogen among the area which limited
by manufacturer. There shall be no spark source in the
limited exhaust area. During measuring, concentration of
Hydrogen should meet following requirements:
a) Hydrogen concentration should be less than 1 % of
gas volume under normal charging operation;
b) Hydrogen concentration should be less than 2% of
gas volume during charging period, when the sudden
failure happened as following
(l)When ventilation device out of work, natural
ventilation should be well enough to preventing hydrogen
gathered; (2)Charging operation should be stop by he
safety device of charger or providing forced ventilation
when the charger out of work; (3)Connections of power
battery are loose; (4)Ventilation pipe fall off.
2) Hydrogen produced during driving
For preventing hydrogen caused burst into flames, it
should be recommended to measuring hydrogen
concentration of vehicle. During measuring, hydrogen
concentration should meet the following requirements:
a) Hydrogen concentration should be less than 1 % of
gas volume under normal driving;
b) Hydrogen concentration should be less than 2% of
gas volume during charging period when the sudden
failure happened
3) Harmful substances
In normal conditions, amount of harmful substances
the power battery produced cannot be dangerous. In
accidents or other faults, more harmful substances would
be released when should make its risk to the minimum,
especially the passenger cabin.
4) The protection of power battery overcorrect
It should set up battery current disconnect device, to
preventing power battery overcorrect. The power battery
current disconnect device should be able to disconnect the
connection of battery package in following situations:
(1) The current limited by vehicle manufactory; (2)
power battery connection circuit appears short circuit.
Power battery current disconnect device should be able to
work in any situation, including the on-board storage
device malfunction.
III. KEEP WORKING AND AVOIDING FAULT
The electric motor drive of EV may appear faults when
facing the special danger situation. So we should take
some measures to ensure that it could work normally and
avoid fault.
A. Requirements of operation safety
1) Requirements of the drive system and the safety of
power connected program
(1) It is finished by at least twice conscious different
continuous actions, that from the "power cut oft" state to
the "travels" state:
(2) "Power cut": drive system closed, vehicles may not
have active action in this state,
(3) "Travel": when using accelerator pedal, the car can
only drive in this state.