DEVICE FOR DRIVING/CONTROLLING AC MOTOR

Provided are hydraulic pumps (32a, 32b) for discharging working oil, a group of hydraulic cylinders (35), a traveling motor (36), an operating device (17) operated in order to control the actuating of the group of hydraulic cylinders (35) and the traveling motor (36), an electric motor (33) driven by the hydraulic pumps (32a, 32b), a battery (41) for outputting DC power, an inverter (43) for inverting the DC power from the battery (41) to AC power and supplying the AC power to the electric motor (33), mode switching means (17a) operated in order to adjust the magnitude of the AC power supplied to the electric motor (33), and a control device (44) for performing control for adjusting the magnitude of the AC power supplied to the electric motor (33).