An electric pump includes a pump unit, a motor and a controller. The pump unit is configured to pump fluid by a rotating operation. The motor is a brushless direct-current motor and configured to rotationally drive the pump unit. The controller is configured to control a current to be supplied to the motor. The controller is configured to switch between voltage control for controlling the current to be supplied to the motor based on a target voltage and current control for controlling the current to be supplied to the motor based on a target current.

A system and a method for driving a motor with a frequency conversion mechanism are provided. The system includes a look-up table module, an oscillator circuit, a multi-frequency signal generator circuit, and a motor driver circuit. The look-up table module stores a preset driving signal. The oscillator circuit generates oscillating signals having different frequencies. The multi-frequency signal generator circuit outputs a multi-frequency signal according to the oscillating signals. One waveform segment of the multi-frequency signal in a modulation region has a first oscillating frequency. Another waveform segment of the multi-frequency signal outside the modulation region has a second oscillating frequency lower than the first oscillating frequency. When a back electromotive force or a phase current of the motor reaches zero within a time interval of the modulation region, the motor driver circuit drives the motor according to the preset driving signal and the multi-frequency signal.

A system and a method for driving a motor with a frequency conversion mechanism are provided. The system includes a look-up table module, an oscillator circuit, a multi-frequency signal generator circuit, and a motor driver circuit. The look-up table module stores a preset driving signal. The oscillator circuit generates oscillating signals having different frequencies. The multi-frequency signal generator circuit outputs a multi-frequency signal according to the oscillating signals. One waveform segment of the multi-frequency signal in a modulation region has a first oscillating frequency. Another waveform segment of the multi-frequency signal outside the modulation region has a second oscillating frequency lower than the first oscillating frequency. When a back electromotive force or a phase current of the motor reaches zero within a time interval of the modulation region, the motor driver circuit drives the motor according to the preset driving signal and the multi-frequency signal.

A system and a method for driving a motor with a frequency conversion mechanism are provided. The system includes a look-up table module, an oscillator circuit, a multi-frequency signal generator circuit, and a motor driver circuit. The look-up table module stores a preset driving signal. The oscillator circuit generates oscillating signals having different frequencies. The multi-frequency signal generator circuit outputs a multi-frequency signal according to the oscillating signals. One waveform segment of the multi-frequency signal in a modulation region has a first oscillating frequency. Another waveform segment of the multi-frequency signal outside the modulation region has a second oscillating frequency lower than the first oscillating frequency. When a back electromotive force or a phase current of the motor reaches zero within a time interval of the modulation region, the motor driver circuit drives the motor according to the preset driving signal and the multi-frequency signal.

A system and a method for driving a motor with a frequency conversion mechanism are provided. The system includes a look-up table module, an oscillator circuit, a multi-frequency signal generator circuit, and a motor driver circuit. The look-up table module stores a preset driving signal. The oscillator circuit generates oscillating signals having different frequencies. The multi-frequency signal generator circuit outputs a multi-frequency signal according to the oscillating signals. One waveform segment of the multi-frequency signal in a modulation region has a first oscillating frequency. Another waveform segment of the multi-frequency signal outside the modulation region has a second oscillating frequency lower than the first oscillating frequency. When a back electromotive force or a phase current of the motor reaches zero within a time interval of the modulation region, the motor driver circuit drives the motor according to the preset driving signal and the multi-frequency signal.

An electric pump includes a pump unit, a motor and a controller. The pump unit is configured to pump fluid by a rotating operation. The motor is a brushless direct-current motor and configured to rotationally drive the pump unit. The controller is configured to control a current to be supplied to the motor. The controller is configured to switch between voltage control for controlling the current to be supplied to the motor based on a target voltage and current control for controlling the current to be supplied to the motor based on a target current.

A device for the regulation of devices which can be regulated with a 0-10 Vdc and/or PWM command is herein disclosed, the device having at least one power supply input, at least one regulation input adapted to receive external regulation signals, a potentiometer comprising a selector element, the potentiometer being configured to provide a manual voltage regulation, and at least one command output configured to output a command signal towards the devices to be regulated. The device further comprises a switching element configured to cause a switching of said device between a first regulation mode, in which the command signal is generated by said device and is manually adjustable through the selector element of said potentiometer, and a second regulation mode, which allows a regulation of the devices to be regulated via the command signal from the command output based on an external device connectable to the regulation input. A system comprising the above device is also disclosed.

A second upper-lower limit clipping unit performs an upper-lower limit clipping with an upper limit torque greater than that of a first upper-lower limit clipping unit, with respect to a value obtained by executing torque ripple correction by subtracting a torque ripple correction amount calculated by a torque ripple correction amount calculation unit, from a torque command subjected to the upper-lower limit clipping by the first upper-lower limit clipping unit. A carrier frequency correction amount calculation unit calculates a carrier frequency correction amount for correcting a carrier frequency of a power converter for driving the motor, in order to reduce losses in the power converter which have been increased by the execution of the torque ripple correction.

A system monitors physical characteristics of or near a motor shaft, such as strain, temperature, voltage, and/or stress. The sensors can sense or measure these characteristics and transmit the measured values wirelessly to a remote user, who can monitor the motor shaft for signs of inefficiency or malfunction. Furthermore, the system can support communications between the remote user and a controlling element of the motor to monitor and adjust the motor shaft to operate with greater efficiency and safety.

A braking system for waterborne propeller driven vessel which, upon activating a brake pedal or similar actuation device causes the vessel to almost immediately stop its forward movement. The system initiates a burst of highly amplified horsepower and torque, created by a controlled pulse of electrical power released from a bank of fully charged ultracapacitors. This pulse of electrical power is sent directly to AC induction-driven motors, causing oversized propellers to immediately rotate astern, thereby generating a reverse thrust in opposition to the vessel's forward movement sufficient to stop the vessel. The horsepower and torque produced by the braking system and operation of the present invention will also cause the oversize propellers to transmit this tremendous power into the water, without cavitation, to assist in stopping vessel movement.