A regenerative drive (30) and method for providing power from such to at least one auxiliary power supply (41, 43) is disclosed. The drive may include a converter (32) and an inverter (34) connected by a DC bus (33), and a controller (54) configured to apply at least one of unipolar modulation and bipolar modulation to the converter (32) and the inverter (34), and to provide about half of the output voltage across the upper portion (130) of the DC bus (33) and about half of the output voltage across the lower portion (136) of the DC bus (33), when the upper and lower portions (130, 136) of the DC bus (33) are unevenly loaded. A first auxiliary power supply (41) may be connected to one of the upper and lower portions (130, 136) of the DC bus (33) and may receive power from the multilevel regenerative drive (30).

A regenerative drive (30) and method for providing power from such to at least one auxiliary power supply (41, 43) is disclosed. The drive may include a converter (32) and an inverter (34) connected by a DC bus (33), and a controller (54) configured to apply at least one of unipolar modulation and bipolar modulation to the converter (32) and the inverter (34), and to provide about half of the output voltage across the upper portion (130) of the DC bus (33) and about half of the output voltage across the lower portion (136) of the DC bus (33), when the upper and lower portions (130, 136) of the DC bus (33) are unevenly loaded. A first auxiliary power supply (41) may be connected to one of the upper and lower portions (130, 136) of the DC bus (33) and may receive power from the multilevel regenerative drive (30).

A motor control device is configured to feedback-control state quantity of a motor or a mechanical load, and the device includes a first notch filter disposed inside a feedback control system and configured to change a frequency component to be removed, a first notch controller configured to change a first notch frequency as a center frequency of the first notch filter, a change rate calculator configured to successively calculate a notch frequency change rate indicating a change amount per unit time of the first notch frequency, and a change rate monitor configured to output a signal indicating that the notch frequency change rate has a value outside a first predetermined range when the notch frequency change rate has the value outside the first predetermined range.

A motor control device includes: a PWM controller that PWM-controls an inverter driving a three-phase motor and including three arm portions, each including a high-side switching element and a low-side switching element connected in series with each other between a first power supply line and a second power supply line connected to a potential lower than a potential of the first power supply line. In an energizing period and a non-energizing period in a case where the three-phase motor is energized from the first power supply line through the PWM-control of the inverter, during a first predetermined period in the energizing period immediately before transition from the energizing period to the non-energizing period, the PWM controller performs a SWEEP of a signal applied to one of the high-side switching element and the low-side switching element, and performs a synchronous rectification control.

A motor control device includes: a PWM controller that PWM-controls an inverter driving a three-phase motor and including three arm portions, each including a high-side switching element and a low-side switching element connected in series with each other between a first power supply line and a second power supply line connected to a potential lower than a potential of the first power supply line. In an energizing period and a non-energizing period in a case where the three-phase motor is energized from the first power supply line through the PWM-control of the inverter, during a first predetermined period in the energizing period immediately before transition from the energizing period to the non-energizing period, the PWM controller performs a SWEEP of a signal applied to one of the high-side switching element and the low-side switching element, and performs a synchronous rectification control.

A fuel cell vehicle may include: an electric traction motor; an inverter; a fuel cell system; a first boost converter including first low voltage terminals connected to a fuel cell and first high voltage terminals connected to the inverter, the first boost converter including a first capacitor connected between positive and negative terminals of the first high voltage terminals; a first relay connected between the first boost converter and the inverter; and a controller, wherein the controller is configured to: shut down the fuel cell system; while a voltage of the fuel cell is higher than a voltage threshold, discharge the first capacitor and maintain a voltage thereof higher than the voltage of the fuel cell; and when the voltage of the fuel cell becomes lower than the voltage threshold, stop discharging the first capacitor and disconnect the first boost converter from the inverter by opening the first relay.

A fuel cell vehicle may include: an electric traction motor; an inverter; a fuel cell system; a first boost converter including first low voltage terminals connected to a fuel cell and first high voltage terminals connected to the inverter, the first boost converter including a first capacitor connected between positive and negative terminals of the first high voltage terminals; a first relay connected between the first boost converter and the inverter; and a controller, wherein the controller is configured to: shut down the fuel cell system; while a voltage of the fuel cell is higher than a voltage threshold, discharge the first capacitor and maintain a voltage thereof higher than the voltage of the fuel cell; and when the voltage of the fuel cell becomes lower than the voltage threshold, stop discharging the first capacitor and disconnect the first boost converter from the inverter by opening the first relay.

A control apparatus includes a controller that controls a motor, a first transmission channel connected to a first power-supply terminal of an alternating-current source that supplies an alternating-current voltage, a second transmission channel connected to a second power-supply terminal of the alternating-current source, and a third transmission channel connected to each of the first transmission channel and the second transmission channel. The controller switches the rotational speed of the motor based on the voltage value of a signal input to the controller in accordance with a first connection status of the first transmission channel and the third transmission channel and a second connection status of the second transmission channel and the third transmission channel.

A control apparatus includes a controller that controls a motor, a first transmission channel connected to a first power-supply terminal of an alternating-current source that supplies an alternating-current voltage, a second transmission channel connected to a second power-supply terminal of the alternating-current source, and a third transmission channel connected to each of the first transmission channel and the second transmission channel. The controller switches the rotational speed of the motor based on the voltage value of a signal input to the controller in accordance with a first connection status of the first transmission channel and the third transmission channel and a second connection status of the second transmission channel and the third transmission channel.

An emergency power supply system for providing hydraulic power and electric power in an aircraft includes a fuel cell having an electric outlet for providing electric power, a conversion unit couplable with at least one of an AC bus and a DC bus and the electric outlet, and at least one hydraulic pump having a reconfigurable electric motor and a motor control unit and being couplable with a hydraulic system for providing hydraulic power. The conversion unit is adapted for converting a supply voltage of the electrical outlet to at least one of an AC voltage matching a predetermined voltage at the AC bus and a DC voltage matching a predetermined voltage at the DC bus. The reconfigurable electric motor is couplable with the fuel cell and the AC bus and is adapted for being operated by the supply of electric power either from the fuel cell or the AC bus.