A motor control system is configured to: determine a current supply limit for an electric motor; receive a current supply of the electric motor; identify one or more motor commands; adjust the one or more motor commands in response to a determination that the current supply is greater than the current supply limit; and selectively control the electric motor using the adjusted one or more motor commands.

Brushless direct current (BLDC) motors are becoming more common, such as in cars and other vehicles. Unreliable BLDC motors or control systems can lead to risk of people's safety. A redundant BLDC control system is provided to control two or more BLDC motors. A safety module controls an enabling switch in each of the motor drivers, so that in response to detecting a fault condition, a currently active BLDC motor is disabled and a redundant BLDC motor is enabled. A digital processor computes and transmits digital signals to all the motor drivers continuously and simultaneously, so that the transition from a currently active BLDC motor to a redundant BLDC motor is smooth and almost unnoticeable.

Brushless direct current (BLDC) motors are becoming more common, such as in cars and other vehicles. Unreliable BLDC motors or control systems can lead to risk of people's safety. A redundant BLDC control system is provided to control two or more BLDC motors. A safety module controls an enabling switch in each of the motor drivers, so that in response to detecting a fault condition, a currently active BLDC motor is disabled and a redundant BLDC motor is enabled. A digital processor computes and transmits digital signals to all the motor drivers continuously and simultaneously, so that the transition from a currently active BLDC motor to a redundant BLDC motor is smooth and almost unnoticeable.

A motor control device includes a power converter that supplies a three-phase voltage to two motors being connected in parallel, a three-phase power line that connects between one of the two motors and the power converter, a branch three-phase power line that connects between the other of the two motors and the power converter, a switching device having two switches that are provided on the branch three-phase power line, a current detection device that detects three-phase currents flowing in the two motors, and a controller. The controller performs a failure determination of the switching device by identifying a phase of a power line in which no current flows in the three-phase power line and the branch three-phase power line, and, when a failure is detected in one of the two switches in the failure determination, controls to change a state of the other switch, which operates normally, to coincide with a state of the failed switch.

A power tool includes a housing, an electric motor, a driver circuit, a speed detection device, and a control device. The driver circuit is electrically connected to the electric motor to drive the electric motor to operate. The speed detection device is configured to acquire a rotational speed of the electric motor. The control device is connected to the speed detection device and the driver circuit and outputs a control signal to the driver circuit to control rotation of the electric motor. The control device is configured to acquire the rotational speed of the electric motor when the electric motor is in a start-up stage, obtain a rotational speed variation of the electric motor within a preset time based on the rotational speed of the electric motor, and turn off the electric motor when the rotational speed variation is less than a rotational speed variation threshold.

A motor drive device that drives motors with one inverter includes a step-out control unit that detects step-out in which the operating frequency of at least one of the motors does not match the inverter output frequency, or the operating frequency of at least one of the motors does not match the operating frequency of another one of the motors, and stops the motors by switching an energization state of the inverter when at least one of the motors is out of step.

A motor drive device that drives motors with one inverter includes a step-out control unit that detects step-out in which the operating frequency of at least one of the motors does not match the inverter output frequency, or the operating frequency of at least one of the motors does not match the operating frequency of another one of the motors, and stops the motors by switching an energization state of the inverter when at least one of the motors is out of step.

A drive system with one or more electrically driven axles, a transmission subsystem, which is drivingly coupled to a drive gearbox of each of the electrically driven axles, first and second motors, which are each drivingly coupled to the transmission subsystem and have different motor characteristics, and a controller. The drive gearbox of each axle transmits rotary power to an associated set of vehicle wheels. The controller controls the first and second motors responsive to at least a torque request. Over a significant portion of the operating range of the drive system, the controller is configured to vary the respective magnitudes of the rotary power provided by the first and second motors to satisfy the torque request in a manner that maximizes a combined efficiency of the motors in a predetermined manner.

A drive system with one or more electrically driven axles, a transmission subsystem, which is drivingly coupled to a drive gearbox of each of the electrically driven axles, first and second motors, which are each drivingly coupled to the transmission subsystem and have different motor characteristics, and a controller. The drive gearbox of each axle transmits rotary power to an associated set of vehicle wheels. The controller controls the first and second motors responsive to at least a torque request. Over a significant portion of the operating range of the drive system, the controller is configured to vary the respective magnitudes of the rotary power provided by the first and second motors to satisfy the torque request in a manner that maximizes a combined efficiency of the motors in a predetermined manner.

A motor control system includes host control circuitry configured to generate a first control command; a plurality of motor control apparatuses configured to control a plurality of motors, respectively, based on the first control command; and reference information output circuitry configured to output reference information to one of the plurality of motor control apparatuses which is configured to control one of the plurality of motors. The reference information relates to control of the plurality of motors. Each of the plurality of motor control apparatuses corresponds to a corresponding motor among the plurality of motors and includes information sharing circuitry configured to share the reference information among the plurality of motor control apparatuses via data communication; command conversion circuitry configured to convert the reference information into a second control command; and motor control circuitry configured to control the corresponding motor based on the second control command.