There is described a method of controlling an inverter supplying power to a permanent magnet AC, PMAC, motor having a plurality of phase windings, The method comprises: selecting a first phase winding of the PMAC motor; electrically connecting the first phase winding to a first DC terminal of a DC link circuit at a first time, and maintaining the connection between the first phase winding and the first DC terminal: determining a flux difference between the first phase winding and a second phase winding of the PMAC motor; selecting a second time to electrically connect the second phase winding to the first DC terminal; electrically connecting the second phase winding to the first DC terminal at the second time; and maintaining the connection between the second phase winding and the first DC terminal. The second time is selected based on the determined flux difference.

A surgical stapler. The surgical stapler includes a drive system, an electric motor, a battery and a control system. The drive system includes a movable drive member. The electric motor is mechanically coupled to the drive system. The battery is electrically couplable to the electric motor. The control system is electrically connected to the electric motor and includes an accelerometer. The control system is configured to control a force applied to the drive system based on an acceleration of the movable drive member.

A surgical stapler. The surgical stapler includes a drive system, an electric motor, a battery and a control system. The drive system includes a movable drive member. The electric motor is mechanically coupled to the drive system. The battery is electrically couplable to the electric motor. The control system is electrically connected to the electric motor and includes an accelerometer. The control system is configured to control a force applied to the drive system based on an acceleration of the movable drive member.

A system includes a remote electronic tilt phase shifter module, a motor, a mechanical linkage that connects the motor to the remote electronic tilt phase shifter module, a current management circuit that generates a motor control signal responsive to a current control signal, and a driver circuit that is configured to selectively connect the motor to a power supply in response to the motor control signal.

A control circuit includes a first high-side transistor coupled between a voltage supply terminal and the first terminal of a DC motor and a second high-side transistor coupled between the voltage supply terminal and the second terminal of the DC motor. The control circuit includes a first low-side transistor coupled between a ground terminal and the first terminal of the DC motor and a second low-side transistor coupled between the ground terminal and the second terminal of the DC motor. The control circuit includes a first pull-up resistor coupled between the voltage supply terminal and a gate terminal of the first low-side transistor and a second pull-up resistor coupled between the voltage supply terminal and a gate terminal of the second low-side transistor. The pull-up resistors apply bias currents to turn ON the first and second low-side transistors to provide a conductive path to brake the DC motor.

A modulation routine in a motor drive under lightly loaded conditions which prevents DC bus voltage pump-up includes both active states and zero states. In a first zero state, each phase of the motor is connected to a negative rail of the DC bus, and in a second zero state, each phase of the motor is connected to a positive rail of the DC bus. When motor is lightly loaded or unloaded such that DC bus voltage pump-up may occur, the two zero states are utilized in an uneven manner. The specific division of the zero state between the first and second zero states may be selected in a manner that prevents the DC bus voltage pump-up from occurring.

A system for controlling an electromechanical actuator for setting a collective offset for a helicopter on a blade-specific basis, wherein the system comprises at least one actuator, the length and position of which can be adjusted electromechanically within a mechanically limited range, a power electronics that is configured to adjust the actuator by means of a servomotor in two directions, specifically toward a positive collective offset or toward a negative collective offset, and a first microelectronics system that is configured to control the power electronics such that positive and negative collective offsets can be set. The system also includes a second microelectronics system, which is configured to override the actuation of the first microelectronics system in order to act on the adjustment of the actuator, and by a first control line, which is configured to activate or deactivate the second microelectronics system through an external electrical signal.

An arc quenching device, which prevents a load device from displaying an unnecessary behavior during starting of a power supply, includes: a semiconductor switch connected in parallel to a first switch which is mechanical; a power supply circuit configured to use a voltage which is generated between both contact points of the first switch to output a voltage which causes the semiconductor switch to turn on; and a second switch configured to cause its open state to prevent the semiconductor switch from turning on.

An arc quenching device, which prevents a load device from displaying an unnecessary behavior during starting of a power supply, includes: a semiconductor switch connected in parallel to a first switch which is mechanical; a power supply circuit configured to use a voltage which is generated between both contact points of the first switch to output a voltage which causes the semiconductor switch to turn on; and a second switch configured to cause its open state to prevent the semiconductor switch from turning on.

The technique of the present disclosure has an object to perform PWM control of DC motors with a CPU and a motor drive circuit connected by a smaller number of serial interfaces, and provides a motor drive circuit comprising: energization control units to switch the directions of energization of motors by using switching elements to be driven by PWM signals; a reception unit to receive data indicating energization of the motor and the duty ratio of the PWM signal for each energization control unit from a computation apparatus by serial communication; a first signal generation unit to generate a motor control signal for controlling energization of the motor and the duty ratio based on the data for each energization control unit; and a second signal generation unit to generate the PWM signal having the duty ratio set according to the corresponding motor control signal for each energization control unit.