A power conversion device includes a switching circuitry configured to supply a driving alternating current (AC) power to a motor of a controlled object that includes the motor and a movable part driven by the motor, and detect an abnormality in the controlled object based on the index information acquired.

A control system for an electric motor includes a power input calculating module configured to calculate power input to the electric motor. A power output calculating module is configured to calculate power output by the electric motor. A power loss calculating module is configured to calculate power loss in the electric motor based on the power input and the power output. A fault module is configured to compare the power loss in the electric motor to one or more predetermined power loss thresholds and to selectively alter operation of the electric motor based on the comparison.

The rectifier includes: a main circuit unit configured to perform power conversion between AC power on a side of a three-phase AC power supply and DC power on a DC side by rectifying operation of a rectifying device and ON-OFF operation of a switching device; a power calculation unit configured to calculate a value of a power flowing between the side of the three-phase AC power supply and the DC side via the main circuit unit; and a control unit configured to perform control to execute the ON-OFF operation of the switching device, wherein the control unit changes a length of an ON period per cycle in the ON-OFF operation executed on the switching device according to the value of the power calculated by the power calculation unit.

An unmanned aerial vehicle includes a fuselage, a motor mounted at the fuselage, and a control apparatus configured to control the motor. The control apparatus includes one or more processors configured to obtain a present electrical parameter of a battery configured to power the motor, calculate a compensation amount of a control signal of the motor according to the present electrical parameter, and modify the control signal according to the compensation amount.

A motor controller includes a current controller configured to generate control signals for driving a permanent magnet synchronous motor (PMSM), where the current controller is configured to measure voltage information and current information of the PMSM; a power constant controller configured to receive the voltage information and the current information, and generate a first target speed based on a target power of the PMSM and based on the voltage information and the current information; first signal generator configured to generate a second target speed; a speed constant controller coupled between the power constant controller and the current controller, wherein the speed constant controller is configured to switchably receive the first target speed and the second target speed, and regulate a motor speed of the PMSM based on the received first target speed or the received second target speed.

A motor controller includes a power constant controller configured to receive a target power of a permanent magnet synchronous motor (PMSM) and generate a first target speed based on the target power; a first signal generator configured to generate a second target speed; a speed constant controller switchably coupled to the power constant controller and the first signal generator, where the speed constant controller is configured to switchably receive the first target speed and the second target speed, and regulate a motor speed of the PMSM based on the received first target speed or the received second target speed; a first switch configured to switchably couple the speed constant controller to the power constant controller to receive the first target speed or the second target speed; and a first switch controller configured to control a switching state of the first switch based on the motor speed of the PMSM.

The present invention relates to a method for determining a state of a bearing of a three phase electric machine, the electric machine having a rotor, which is supported by the bearing, the electric machine being connected to a three phase inverter for supplying the electric machine with electric power, the three phase inverter being controlled to apply a pulse width modulation with a predefined scheme to create three phase currents, the method comprises: determining a first phase current provided to the electric machine; determining a second phase current provided to the electric machine, the second phase current being different to the first phase current; determining the power spectral density of the park's vector based on the first phase current and the second phase current; determining an amplitude of the power at a predefined frequency of the power spectral density, wherein the predefined frequency depends on the rotational speed of the rotor and the scheme of the pulse width modulation; comparing the amplitude of the power at the predefined frequency with a predefined power value; anddetermining, based on the comparison, whether a failure of the bearing has occurred or the bearing is degraded.

Methods and systems are provided for adjusting a torque delivered to wheels of an electrically propelled vehicle based on a battery discharge power. In one example, a method may include, during conditions of a lower than threshold battery output power, reducing the torque delivered to the vehicle wheels from a deliverable torque output.

A power system includes: a first power circuit, having a first battery; a second power circuit, having a second battery, wherein a used voltage range of the second battery with respect to a closed circuit voltage overlaps with the first battery, and a static voltage of the second battery is lower than the first battery; a voltage converter, converting a voltage between the power circuits; a power converter, converting power between the first power circuit and a driving motor; and a management ECU and a motor ECU, operating the power converter based on required power. The management ECU and the motor ECU calculates limit power with respect to output power of the first battery based on an internal state of the second battery, and operates the power converter so that the output power of the first battery does not exceed the limit power.

A motor control system includes a motor; a motor and a motor control circuit coupled to the motor to provide power to the motor. The motor control circuit includes a power feedback loop having a power reference circuit to provide a reference power level and a power control circuit configured to provide a constant power level to the motor so that the motor operates with a substantially constant power output. The constant power level is proportional to the reference power level. Thus, the motor also provides substantially constant torque when the motor is at a constant speed.