A comminuting machine includes a frame, a comminuting rotor coupled to the frame, and a rotary drive coupled to the rotor. The rotary drive including a controller, a multi-phase motor connected to the controller, a set of contactors disposed between the controller and the multi-phase motor for selectively providing driving motive force to the multi-phase motor, and at least one rheostat disposed between the controller and the multi-phase motor, in parallel with the first set of contactors, for selectively providing a stopping resistance to the multi-phase motor to effect frictionless braking of the comminuting rotor, wherein the controller is configured to operate the set of contactors and the at least one rheostat to single phase lines of the multi-phase motor for providing the stopping resistance.

A controller for a brushless direct-current motor having an upstream converter, which has a half-bridge having a pair of switching means for each phase winding of the motor, includes a measuring device or has a signal connection to a measuring device. The measuring device is associated with a half-bridge and by means of the measuring device, the induced voltage, the counterelectromotive force of a phase winding, can be detected for rotor position detection in the current-free state, for which purpose the controller, in an operating mode that causes the braking and in which the switching means cause a short circuit of the phase windings, briefly opens the switching means associated with the measuring device in order to determine a rotor motion.

A controller for a brushless direct-current motor having an upstream converter, which has a half-bridge having a pair of switching means for each phase winding of the motor, includes a measuring device or has a signal connection to a measuring device. The measuring device is associated with a half-bridge and by means of the measuring device, the induced voltage, the counterelectromotive force of a phase winding, can be detected for rotor position detection in the current-free state, for which purpose the controller, in an operating mode that causes the braking and in which the switching means cause a short circuit of the phase windings, briefly opens the switching means associated with the measuring device in order to determine a rotor motion.

Embodiments of systems and methods for operating a power tailgate system are disclosed. A vehicle includes a rotatable element structured for operable connection with, and disconnection from, a tailgate when the rotatable element resides in a predetermined tailgate removal orientation. A motor is connected with the rotatable element for interdependent movement, and a motor circuit is provided for the motor. During a driving event, the system identifies when no tailgate is connected with the rotatable element. If no tailgate is connected with the rotatable element, the system determines if the rotatable element resides in the predetermined tailgate removal orientation. If the rotatable element resides in the predetermined tailgate removal orientation, the system may check the rotatable element against rotation during the driving event by operating a motor circuit to electrically brake the motor to prevent the rotatable element from rotating out of the predetermined tailgate removal orientation.

Even in the case in which an overvoltage is generated when a vehicle is in a non-operation state, the overvoltage can be suppressed. A power conversion device is connected to a three-phase motor mounted on a vehicle and includes an inverter circuit, a gate drive substrate, and a motor control substrate. In the motor control substrate, when the vehicle is in the non-operation state and a regenerative voltage applied from the three-phase motor to the inverter circuit becomes equal to or more than a predetermined threshold value, a power supply circuit supplies operation power to a control circuit. The control circuit starts when the operation power is supplied from the power supply circuit and outputs gate control signals to a driver circuit of the gate drive substrate, such that regenerative energy according to the regenerative voltage is consumed between the three-phase motor and the inverter circuit.

Even in the case in which an overvoltage is generated when a vehicle is in a non-operation state, the overvoltage can be suppressed. A power conversion device is connected to a three-phase motor mounted on a vehicle and includes an inverter circuit, a gate drive substrate, and a motor control substrate. In the motor control substrate, when the vehicle is in the non-operation state and a regenerative voltage applied from the three-phase motor to the inverter circuit becomes equal to or more than a predetermined threshold value, a power supply circuit supplies operation power to a control circuit. The control circuit starts when the operation power is supplied from the power supply circuit and outputs gate control signals to a driver circuit of the gate drive substrate, such that regenerative energy according to the regenerative voltage is consumed between the three-phase motor and the inverter circuit.

A system includes a grid coupled to an electrical bus; an electrical power modulation device coupled to the electrical bus that can output modified electrical power received from the electrical bus; a blower motor coupled to the electrical power modulation device that can receive the modified electrical power output and can provide a stream of air to affect a temperature of the grid, and a controller. A speed of the blower motor may be based at least in part on an amount of the modified electrical power. The controller can receive an operating parameter, and is responsive to that parameter by causing the electrical power modulation device to vary the amount of the modified electrical power. A blower motor speed may be controlled based at least in part on the operating parameter.

A system includes a grid coupled to an electrical bus; an electrical power modulation device coupled to the electrical bus that can output modified electrical power received from the electrical bus; a blower motor coupled to the electrical power modulation device that can receive the modified electrical power output and can provide a stream of air to affect a temperature of the grid, and a controller. A speed of the blower motor may be based at least in part on an amount of the modified electrical power. The controller can receive an operating parameter, and is responsive to that parameter by causing the electrical power modulation device to vary the amount of the modified electrical power. A blower motor speed may be controlled based at least in part on the operating parameter.

Provided is a swing door operator (110) for moving a door leaf (120) between a first position and a second position. The swing door operator (110) is arranged to operate in a powered and a powerless mode and comprises a permanent magnet DC motor (310). The motor (310) is arranged to move the door leaf (120) at least from the second position to the first position in the powered mode. The swing door operator (110) further comprises a mechanical drive unit (320), arranged to move the door leaf from the first position to the second position in the powerless mode. In the powerless mode, at least one resistive device is electrically connected in parallel with the motor (310) and arranged to limit a current generated by the motor (310) in response to the movement of the door leaf (120) from the first position to the second position by means of the mechanical drive unit (320). A method for controlling the swing door operator is also provided.

Provided is a swing door operator (110) for moving a door leaf (120) between a first position and a second position. The swing door operator (110) is arranged to operate in a powered and a powerless mode and comprises a permanent magnet DC motor (310). The motor (310) is arranged to move the door leaf (120) at least from the second position to the first position in the powered mode. The swing door operator (110) further comprises a mechanical drive unit (320), arranged to move the door leaf from the first position to the second position in the powerless mode. In the powerless mode, at least one resistive device is electrically connected in parallel with the motor (310) and arranged to limit a current generated by the motor (310) in response to the movement of the door leaf (120) from the first position to the second position by means of the mechanical drive unit (320). A method for controlling the swing door operator is also provided.