A method of controlling a motor drive having a normal mode wherein a DC link voltage is charged using an AC (e.g. mains) power supply and an emergency mode wherein the DC link voltage is charged using a DC supply (e.g. from a battery) is described. In the normal mode of operation, if the DC link voltage falls below a threshold indicative of the AC power supply being lost, the emergency mode is entered, typically following an intervening coast mode (during which the motor is not driven). Similarly, in the emergency mode, if the DC link voltage rises above a threshold indicative of the AC power supply being restored, the normal mode is entered, typically following an intervening coast mode.

A control device of an automatic drive vehicle includes: an information acquisition unit that acquires power generator information as information on a power generator provided in the automatic drive vehicle; an operation control unit that switches between a first state in which automatic driving of the automatic drive vehicle is executed without restriction and a second state in which the automatic driving is partially or entirely restricted; and a determination unit that determines whether to perform switching to the second state by the operation control unit.

A machine tool includes a drive unit driving a tool for machining a workpiece, and a control unit controlling the drive unit. The machine tool further includes an abnormality determining unit that determines whether machining can be continued, based on operation information of the drive unit, and a power failure detection unit that switches the power source of the control unit from a normal power supply unit to an emergency power supply unit if power failure is detected, and switches the power source from the emergency power supply unit to the normal power supply unit if recovery of power supply is detected after power failure. The control unit stops operation of the drive unit when power failure is detected, and thereafter, if recovery of power supply is detected, and the abnormality determining unit determines that machining can be continued, the control unit drives the drive unit, thereby automatically resuming machining.

A control device of an automatic drive vehicle includes: an information acquisition unit that acquires power generator information as information on a power generator provided in the automatic drive vehicle; an operation control unit that switches between a first state in which automatic driving of the automatic drive vehicle is executed without restriction and a second state in which the automatic driving is partially or entirely restricted; and a determination unit that determines whether to perform switching to the second state by the operation control unit.

This disclosure describes at least embodiments of an aircraft monitoring system for an electric or hybrid airplane. The aircraft monitoring system can be constructed to enable the electric or hybrid aircraft to pass certification requirements relating to a safety risk analysis. The aircraft monitoring system can have different subsystems for monitoring and alerting of failures of a component, such as a battery pack, a motor controller, and/or a motors. The failures that pose a greater safety risk may be monitored and indicated by one or more subsystems without use of programmable components.

A hybrid electric aircraft propulsion system and method of operation are described. The system comprises a thermal engine, a generator coupled to the thermal engine, a first electric propulsor operatively connected to the generator to receive alternating current (AC) electric power therefrom, a second electric propulsor, a generator inverter operatively connected to the generator to convert AC electric power to direct current (DC) electric power, and a first motor inverter operatively connected to the generator inverter and selectively connected to one of the first electric propulsor and the second electric propulsor and configured to receive the DC electric power and provide the first electric propulsor and the second electric propulsor with AC electric power, respectively.

A control device configured to control operation of an electric motor of which a rotational shaft is rotatable by an external force which servo-controls the electric motor by an inverter circuit when a voltage value between power-supply input terminals of the inverter circuit is detected to be at or above a given voltage value required for the servo-control of the electric motor, and applies dynamic braking to the electric motor by forming a short circuit in the inverter circuit when the voltage value between the power-supply input terminals of the inverter circuit is detected to be below the given voltage value.

A motor actuator of the present invention includes, between a battery and an inverter, a first solid state relay and a second solid state relay in which directions of parasitic diodes are opposite to each other. When supply of power from the battery to the inverter is to be interrupted, the first solid state relay is brought into an OFF state or all of a plurality of field effect transistors are brought into the OFF state, and then the second solid state relay is brought into the OFF state.

There is described a method and system for operating a hybrid electric aircraft propulsion system. The method comprises modulating AC electric power applied to a first electric propulsor or a second electric propulsor from at least one motor inverter to synchronize the frequency of the first electric propulsor or the second electric propulsor with the frequency of a generator.

A rotary-machine control device includes: a connection switching device switching a connection state of stator windings of a rotary machine; a current detection unit detecting a rotary machine current flowing in the rotary machine; a voltage application unit applying voltage to the rotary machine; a control unit generating a voltage command provided to the voltage application unit and outputting a switching command to switch the connection state to the connection switching device; and an open-phase determination unit determining presence or absence of disconnection in the rotary machine or presence or absence of disconnection of a power distribution line to the rotary machine. During rotation of the rotary machine, the control unit outputs the switching command and the open-phase determination unit determines presence or absence of disconnection.