The utility model relates to a pre-charging loop of an
energy storage high-
voltage box. The pre-charging loop comprises a first circuit, a second circuit, a first
branch circuit, a second
branch circuit and a seventh switch. In a
normal state, the controller controls the third switch to be switched on, and the first circuit, the fourth
branch circuit and the second circuit form a main loop. When the battery is charged, the fourth switch, the seventh switch and the tenth switch are switched on, the ninth switch, the fifth switch and the third switch are switched off, the first circuit, the first branch circuit, the second branch circuit and the second circuit form a pre-charging loop, and the first
resistor and the second
resistor are connected in series to limit current. When the batteries are in a discharging state and the
voltage difference between the battery clusters is larger than the specified
voltage difference, the fourth switch, the fifth switch and the ninth switch are closed, the third switch and the seventh switch are disconnected, and the first
resistor and the second resistor are connected in parallel to control current balance. The pre-charging loop of the
energy storage high-voltage box can meet the resistance requirements of each state of the battery, reduce the heating value of the resistor and prolong the service life.