To provide an electric industrial vehicle with a power supply system device, capable of efficiently driving a drive unit both at regeneration and at power running through a simple computation method.
The power supply system device 3 of the electric industrial vehicle is comprised of a lead battery 2, a large-capacitance capacitor 13, a DC-DC converter 12 that controls the voltage of the large-capacitance capacitor 13, and a controller 11 that controls the charging and discharging power of the lead battery 2 and the large-capacitance capacitor 13. When electric motors 4, 6 as a driving source of the electric industrial vehicle are under a power running operation, the controller 11 determines a current allocation between the lead battery 2 and the large-capacitance capacitor 13 so that loss in the power supply system device 3 is minimized. The decision is carried out based on the internal resistances of the lead battery 2 and the large-capacitance capacitor 13 and the load required power of the electric motors 4, 6.
IKIMI TAKASHI
IZUMI SHIHO
MORIKI SHUICHI
SHONO NOBUO
