A control apparatus is applied to a system that includes a rotating electric machine and an inverter. The inverter has, for each of a plurality of phases, upper-arm and lower-arm switches each of which has a diode connected in antiparallel thereto. The control apparatus includes an all-phase short-circuiting unit and a single-phase short-circuiting unit. The all-phase short-circuiting unit performs all-phase short-circuit control of turning on, for example, all the upper-arm switches of the plurality of phases while turning off all the lower-arm switches of the plurality of phases. The single-phase short-circuiting unit performs, in a regenerative drive state of the rotating electric machine and prior to execution of the all-phase short-circuit control, single-phase short-circuit control of turning on one of the upper-arm and lower-arm switches of one of the plurality of phases, turning off the other switch of the phase and turning off all the switches of the remaining phases.

A control apparatus is applied to a system that includes a rotating electric machine and an inverter. The inverter has, for each of a plurality of phases, upper-arm and lower-arm switches each of which has a diode connected in antiparallel thereto. The control apparatus includes an all-phase short-circuiting unit and a single-phase short-circuiting unit. The all-phase short-circuiting unit performs all-phase short-circuit control of turning on, for example, all the upper-arm switches of the plurality of phases while turning off all the lower-arm switches of the plurality of phases. The single-phase short-circuiting unit performs, in a regenerative drive state of the rotating electric machine and prior to execution of the all-phase short-circuit control, single-phase short-circuit control of turning on one of the upper-arm and lower-arm switches of one of the plurality of phases, turning off the other switch of the phase and turning off all the switches of the remaining phases.

A power tool is provided including a housing, a brushless motor disposed within the housing, a power switch circuit that supplies power from a power source to the brushless motor, and a controller configured to apply a drive signal to the power switch circuit to control the supply of power to the brushless motor. The controller is configured to receive at least one signal associated with a phase current of the motor, detect an angular position of the rotor based on the phase current of the motor within a variable speed range of zero to at least 15,000 rotations-per-minute (RPM), and control the drive signal based on the detected angular position of the rotor to electronically commutate the motor within a torque range of zero to at least 15 newton-meters (N.m.) and a power output of zero to at least 1500 watts.

A power tool is provided including a housing, a brushless motor disposed within the housing, a power switch circuit that supplies power from a power source to the brushless motor, and a controller configured to apply a drive signal to the power switch circuit to control the supply of power to the brushless motor. The controller is configured to receive at least one signal associated with a phase current of the motor, detect an angular position of the rotor based on the phase current of the motor within a variable speed range of zero to at least 15,000 rotations-per-minute (RPM), and control the drive signal based on the detected angular position of the rotor to electronically commutate the motor within a torque range of zero to at least 15 newton-meters (N.m.) and a power output of zero to at least 1500 watts.

A power tool is provided including a housing, a brushless motor disposed within the housing, a power switch circuit that supplies power from a power source to the brushless motor, and a controller configured to apply a drive signal to the power switch circuit to control the supply of power to the brushless motor. The controller is configured to receive at least one signal associated with a phase current of the motor, detect an angular position of the rotor based on the phase current of the motor within a variable speed range of zero to at least 15,000 rotations-per-minute (RPM), and control the drive signal based on the detected angular position of the rotor to electronically commutate the motor within a power output of zero to at least 1500 watts.

A power tool is provided including a housing, a brushless motor disposed within the housing, a power switch circuit that supplies power from a power source to the brushless motor, and a controller configured to apply a drive signal to the power switch circuit to control the supply of power to the brushless motor. The controller is configured to receive at least one signal associated with a phase current of the motor, detect an angular position of the rotor based on the phase current of the motor within a variable speed range of zero to at least 15,000 rotations-per-minute (RPM), and control the drive signal based on the detected angular position of the rotor to electronically commutate the motor within a power output of zero to at least 1500 watts.

A brushless DC motor system control method provided is based on a hybrid energy storage unit. The HESU topology is designed, and the output of the designed HESU is connected to the input of three-phase inverter, and the output of three-phase inverter is connected with the three-phase windings of the BLDCM. In braking operation, two kinds of braking vectors are constructed according to the HESU and three-phase inverter. Moreover, through the combined action of the two vectors, the braking torque control is achieved and meanwhile the braking energy is fed back to the supercapacitor. In electric operation, four kinds of electric vectors are constructed according to the HESU and three-phase inverter. Moreover, the power sharing control between battery and supercapacitor is realized by different vectors action during motor acceleration mode, and the torque ripple in commutation period is suppressed by different vectors action during motor constant speed mode.

A brushless DC motor system control method provided is based on a hybrid energy storage unit. The HESU topology is designed, and the output of the designed HESU is connected to the input of three-phase inverter, and the output of three-phase inverter is connected with the three-phase windings of the BLDCM. In braking operation, two kinds of braking vectors are constructed according to the HESU and three-phase inverter. Moreover, through the combined action of the two vectors, the braking torque control is achieved and meanwhile the braking energy is fed back to the supercapacitor. In electric operation, four kinds of electric vectors are constructed according to the HESU and three-phase inverter. Moreover, the power sharing control between battery and supercapacitor is realized by different vectors action during motor acceleration mode, and the torque ripple in commutation period is suppressed by different vectors action during motor constant speed mode.

A power tool is provided including a housing, a brushless motor disposed within the housing, a power switch circuit that supplies power from a power source to the brushless motor, and a controller configured to receive at least one signal associated with a phase current of the motor, detect an angular position of the rotor based on the phase current of the motor, and apply a drive signal to the power switch circuit to control a commutation of the motor based on the detected angular position of the rotor. The controller detects an initial sector within which the rotor is located at start-up, apply the drive signal so as to rotate the motor to a parking angle associated with the detected initial sector, and control a commutation sequence to drive the motor beginning at the parking angle.

A power tool is provided including a housing, a brushless motor disposed within the housing, a power switch circuit that supplies power from a power source to the brushless motor, and a controller configured to receive at least one signal associated with a phase current of the motor, detect an angular position of the rotor based on the phase current of the motor, and apply a drive signal to the power switch circuit to control a commutation of the motor based on the detected angular position of the rotor. The controller detects an initial sector within which the rotor is located at start-up, apply the drive signal so as to rotate the motor to a parking angle associated with the detected initial sector, and control a commutation sequence to drive the motor beginning at the parking angle.