Electric working machine

An electric working machine comprising:

• a battery;
• an electric motor;
• an inverter to supply electric power from the battery to the electric motor to drive the electric motor;
• a hydraulic pump to be actuated by power of the electric motor;
• a hydraulic device to be actuated by a hydraulic pressure of a hydraulic fluid delivered from the hydraulic pump;
• a fluid temperature detector to detect a temperature of the hydraulic fluid;
• a rotation speed detector to detect a rotation speed of the electric motor;
• a specifier to be operated to specify the rotation speed of the electric motor;
• and
• a controller configured or programmed to control driving of the inverter and the electric motor;
• wherein
• the controller is configured or programmed to:
• gradually increase the rotation speed of the electric motor such that the rotation speed of the electric motor reaches a target rotation speed in a longer time when the electric motor is started in a state in which the temperature of the hydraulic fluid detected by the fluid temperature detector is lower than or equal to a predetermined temperature than when the electric motor is started in a state in which the temperature of the hydraulic fluid is higher than the predetermined temperature, and
• when the electric motor is started in a state in which the temperature of the hydraulic fluid is lower than or equal to the predetermined temperature:
• determine a delay time, the delay time being a time until the rotation speed of the electric motor is stabilized at the target rotation speed, the target rotation speed being the rotation speed specified by the specifier;
• and
• gradually increase the rotation speed of the electric motor such that the rotation speed of the electric motor is stabilized at the target rotation speed after the delay time has elapsed from when the rotation speed of the electric motor starts to be increased.