Wide bandgap motor drive with field-operated-control for power tools

A method for controlling a motor of a power tool, the method comprising:

• receiving, using a controller of the power tool, speed command;
• generating, using the controller, field-oriented control (FOC) control reference signals based on the speed command;
• generating, using the controller, pulse-width modulated (PWM) signals based on the FOC control reference signals;
• and
• switching a plurality of Wide Bandgap Semiconductors (WBS) field effect transistors (FETs) of a power switching network electrically connected between a power input of the power tool and a motor of the power tool, the plurality of WBS FETS being switched between a conducting state and a non-conducting state based on the PWM signals at a switching frequency of at least 50 kHz.

A power tool comprising:

• a power input;
• a variable speed trigger;
• a motor including a speed sensor;
• a power switching network electrically connected between the power input and the motor and including a plurality of Gallium Nitride (GaN) High Electron Mobility Transistors (HEMTs);
• and
• a controller electronically connected to the power switching network and configured to
• receive, via the variable speed trigger, a speed command;
• determine, using the speed sensor, a motor speed;
• generate FOC control reference signals based on the speed command and the motor speed;
• and
• generate pulse-width modulated (PWM) signals based on the FOC control reference signals, wherein the plurality of GaN HEMTs are switched between a conducting state and a non-conducting state based on the PWM signals at a switching frequency of at least 50 kHz.