A work machine, comprising: - a first control device to control the entirety of a vehicle body of the work machine; and - a plurality of power control units, wherein the work machine is further comprising: - a carriage; - an upper structure mounted on the carriage in a revolvable manner; - an engine which is an internal combustion engine; - an assist generator motor to provide power assistance to the engine and to generate electric power; and - a revolving electric motor to drive the upper structure, wherein on the basis of a detection signal corresponding to an engine rotational speed, the first control device is configured to acquire information about an engine driving state in which the engine rotational speed is equal to or greater than a predetermined value, wherein the plurality of power control units include: - a first power control unit for controlling the assist generator motor mounted on an installation site dedicated to the first power control unit, and - a second power control unit for controlling the revolving electric motor mounted on an installation site dedicated to the second power control unit, the first power control unit is configured to acquire the information about the engine driving state output from the first control device and a motor state signal which serves as the driving state signal and indicates that a motor rotational speed is equal to or greater than a predetermined value so as to set a function required to control the assist generator motor, and the second power control unit is configured to acquire the information about the engine driving state output from the first control device and a motor state signal which serves as the driving state signal and indicates that the motor rotational speed is less than the predetermined value so as to set a function required to control the revolving electric motor. - a first control device to control the entirety of a vehicle body of the work machine; and - a plurality of power control units, wherein the work machine is further comprising: - a carriage; - an upper structure mounted on the carriage in a revolvable manner; - an engine which is an internal combustion engine; - an assist generator motor to provide power assistance to the engine and to generate electric power; and - a revolving electric motor to drive the upper structure, wherein on the basis of a detection signal corresponding to an engine rotational speed, the first control device is configured to acquire information about an engine driving state in which the engine rotational speed is equal to or greater than a predetermined value, wherein the plurality of power control units include: - a first power control unit for controlling the assist generator motor mounted on an installation site dedicated to the first power control unit, and - a second power control unit for controlling the revolving electric motor mounted on an installation site dedicated to the second power control unit, the first power control unit is configured to acquire the information about the engine driving state output from the first control device and a motor state signal which serves as the driving state signal and indicates that a motor rotational speed is equal to or greater than a predetermined value so as to set a function required to control the assist generator motor, and the second power control unit is configured to acquire the information about the engine driving state output from the first control device and a motor state signal which serves as the driving state signal and indicates that the motor rotational speed is less than the predetermined value so as to set a function required to control the revolving electric motor. on the basis of a detection signal corresponding to an engine rotational speed, the first control device is configured to acquire information about an engine driving state in which the engine rotational speed is equal to or greater than a predetermined value, wherein the plurality of power control units include: - a first power control unit for controlling the assist generator motor mounted on an installation site dedicated to the first power control unit, and - a second power control unit for controlling the revolving electric motor mounted on an installation site dedicated to the second power control unit, - a first power control unit for controlling the assist generator motor mounted on an installation site dedicated to the first power control unit, and - a second power control unit for controlling the revolving electric motor mounted on an installation site dedicated to the second power control unit, the first power control unit is configured to acquire the information about the engine driving state output from the first control device and a motor state signal which serves as the driving state signal and indicates that a motor rotational speed is equal to or greater than a predetermined value so as to set a function required to control the assist generator motor, and the second power control unit is configured to acquire the information about the engine driving state output from the first control device and a motor state signal which serves as the driving state signal and indicates that the motor rotational speed is less than the predetermined value so as to set a function required to control the revolving electric motor.