CIRCULAR SAW

Disclosed is a circular saw， including a control unit having a signal processing unit. the signal processing unit is configured to collect a bus current and/or a phase current of the motor， and output a second drive signal to the drive circuit after the bus current and/or the phase current of the motor being processed by the signal processing unit， so that the motor charges a battery pack with a charging current less than or equal to 50A. A control method may independently adjust the current of the motor in the circular saw by optimizing the processing for the phase current and/or the bus current of the motor， and feed back electric energy generated by the motor to the power supply to optimize the utilization efficiency of the power supply. By adopting a power tool such as the circular saw， energy consumption characteristics are better， effective working time may be extended to 1.2 times or more the length of the existing one， overall cost may be further reduced， and a package may be easily miniaturized.