An apparatus includes a multi-channel DC bus assembly comprising a first channel and a second channel, a first electromechanical device coupled to a positive DC link of the first channel, and a second electromechanical device coupled to a positive DC link of the second channel. A first DC-to-AC voltage inverter is coupled to the positive DC link of the first channel and a second DC-to-AC voltage inverter is coupled to the positive DC link of the second channel. The apparatus further includes a bi-directional voltage modification assembly coupled to the positive DC link of the second channel and a first energy storage system electrically coupled to the first electromechanical device.

In an electric motor, a magnetic bearing generates an electromagnetic force between multiple permanent magnets and a coil and rotatably supports an other side of a rotation shaft in an axis line direction. The rotation shaft is configured to be capable of being inclined with a rotation center line using a bearing side of the rotation shaft as a fulcrum. An electronic control device controls a current that flows to the coil such that an axis line of the rotation shaft approaches the rotation center line due to a supporting force which is the electromagnetic force between the multiple permanent magnets and the coil. Accordingly, the rotation shaft is rotatably supported to be freely rotatable by a magnetic bearing and the bearing.

In an electric motor, a magnetic bearing generates an electromagnetic force between multiple permanent magnets and a coil and rotatably supports an other side of a rotation shaft in an axis line direction. The rotation shaft is configured to be capable of being inclined with a rotation center line using a bearing side of the rotation shaft as a fulcrum. An electronic control device controls a current that flows to the coil such that an axis line of the rotation shaft approaches the rotation center line due to a supporting force which is the electromagnetic force between the multiple permanent magnets and the coil. Accordingly, the rotation shaft is rotatably supported to be freely rotatable by a magnetic bearing and the bearing.

Provided is a steering control unit for improving influence of fluctuations in an estimated electrical angle on steering feel. A steering control unit includes a microcomputer that performs sensorless control of the driving of a motor by using an estimated electrical angle estimated by calculation. The microcomputer calculates the estimated electrical angle from a value that is obtained by selectively accumulating a first additional angle or a second additional angle. The microcomputer adjusts a vibration component of fluctuations in the estimated electrical angle by varying the amount of change in the first additional angle and the second additional angle.

Provided is a steering control unit for improving influence of fluctuations in an estimated electrical angle on steering feel. A steering control unit includes a microcomputer that performs sensorless control of the driving of a motor by using an estimated electrical angle estimated by calculation. The microcomputer calculates the estimated electrical angle from a value that is obtained by selectively accumulating a first additional angle or a second additional angle. The microcomputer adjusts a vibration component of fluctuations in the estimated electrical angle by varying the amount of change in the first additional angle and the second additional angle.

An electric lifting frame includes a lifting pedestal and a remote control. The lifting pedestal includes a supporting base, a lifting rod detachably connected to the supporting base, and a transmission mechanism, a motor, a controller, and a power supply provided at the lifting rod. The motor is configured to effect extension and retraction of the lifting rod via the transmission mechanism. The controller is configured to control starting and stopping and a rotation direction of the motor. The power supply is configured to supply electric energy to the motor and the controller. The controller is further configured to determine a remaining capacity of the power supply and calculate a number of remaining available times of use according to the remaining capacity, a power of the motor, and a stroke of the transmission mechanism.

An electric propulsion system includes a polyphase rotary electric machine that imparts motor torque to a load, a traction power inverter module (TPIM) connected to the electric machine, a reconfigurable energy storage system (RESS) connected to the TPIM, and a controller. The RESS has multiple battery modules and a switching circuit. The battery modules are connectable in a series-connected (P-connected) configuration at a first/low battery voltage level, and a series-connected (S-connected) configuration at a second/high battery voltage level that exceeds the first voltage. The controller determines power losses of the electric propulsion system at the first and second battery voltage levels, receives a commanded output torque and output speed of the electric machine, and selects the S-connected or P-connected configuration based on the predetermined power loss and commanded output torque and speed.

An electric propulsion system includes a polyphase rotary electric machine that imparts motor torque to a load, a traction power inverter module (TPIM) connected to the electric machine, a reconfigurable energy storage system (RESS) connected to the TPIM, and a controller. The RESS has multiple battery modules and a switching circuit. The battery modules are connectable in a series-connected (P-connected) configuration at a first/low battery voltage level, and a series-connected (S-connected) configuration at a second/high battery voltage level that exceeds the first voltage. The controller determines power losses of the electric propulsion system at the first and second battery voltage levels, receives a commanded output torque and output speed of the electric machine, and selects the S-connected or P-connected configuration based on the predetermined power loss and commanded output torque and speed.

A rotational electric machine includes a stator configured to generate a rotation magnetic field in response to alternating current; a rotor configured to rotate in response to the rotation magnetic field; a field coil configured to excite the rotor in response to direct current; an acquisition unit configured to acquire manipulation information related to a torque generated by or caused to be generated by the rotor and a rotational state of the rotor; and a motor characteristic control unit configured to control the direct current based on the manipulation information and the rotational state acquired by the acquisition unit to control a motor characteristic.

A power conversion device, mounted on a motor vehicle, has a battery, a power converter, a reactor and a control unit. The power conversion device boosts a battery voltage of the battery, and supplies a boosted voltage to a motor generator mounted on a motor vehicle. The power conversion device transmits electric power generated by the motor generator and supplies the generated electric power to the battery through the power converter. The power converter has an upper arm and a lower arm. The upper arm has upper arm side switching elements. The lower arm has lower arm side switching elements which are directly connected to the respective upper arm side switching elements. At least one of the upper arm side switching elements is composed of a MOS FET and at least one of the lower arm side switching elements is composed of an IGBT.