The invention discloses a
discharge circuit for preventing voltages of batteries from flowing backwards and a control method. The
discharge circuit comprises a high-
voltage direct current output module with a positive
electrode and a negative
electrode, wherein each high-
voltage direct current output module is connected with a corresponding high-
voltage direct current distribution unit; a
discharge unit is connected between each high-voltage direct current output module and each high-voltage direct
current distribution unit in parallel; a first switch K1 and a second switch K2 are arranged on the positive
electrode and the negative electrode of each high-voltage direct
current distribution unit respectively; the first switch K1 or the second switch K2 is connected with a
diode D1 or a
diode D2 in series; the negative electrode of the
diode D1 is connected with the positive electrode of a
battery pack; the positive electrode of the diode D2 is connected with the negative electrode of the
battery pack; all high-voltage direct
current distribution units all are connected with the
battery pack; when a
system does not charge a load or the batteries, the voltages of the batteries cannot flow back to input ends due to presence of the diode D1 or the diode D2; and meanwhile, the high-voltage direct current output modules are controlled to be
shut down, so that over-zero separation of the high-voltage direct current distribution units K1 and K2 can be achieved; and damage to a device caused by high-voltage and high-current arc discharge is avoided.