APPARATUS WITH ACTIVE SOFTWARE CLAMPING OF SUPPLY VOLTAGE

摘要

A power tool that includes a motor configured to drive a working element, a power supply that is coupled to the motor to provide power to the motor, a shunt circuit that is coupled to the power supply and the motor, and a controller. The shunt circuit includes a shunt switch and a shunt element and is configured to hold a voltage of the power supply below a high voltage threshold. The shunt switch is switchable between a conducting state, in which the shunt switch conducts current through the shunt element, and a non-conducting state, in which the shunt switch does not conduct current through the shunt element. The controller is coupled to the motor, the power supply, and the shunt circuit and is configured to determine the voltage of the power supply, and control the shunt switch based on the voltage from the power supply.

主权项

1. A power tool comprising:
a motor configured to drive a working element; a power supply coupled to the motor to provide power to the motor; a shunt circuit coupled to the power supply and the motor, the shunt circuit configured to hold a voltage of the power supply below a high voltage threshold, the shunt circuit including a shunt element and a shunt switch, the shunt switch switchable between
a conducting state, in which the shunt switch enables the shunt element to conduct current, anda non-conducting state, in which the shunt switch prevents the shunt element from conducting current; a controller coupled to the motor, the power supply, and the shunt circuit, the controller configured to
determine the voltage of the power supply, andcontrol the shunt switch based on the voltage from the power supply.