An electrical drive system for an aircraft includes: at least one first and one second electrical direct voltage sources for supplying a direct voltage, and a first and a second electrical machine modules configured to convert electrical alternating voltage into mechanical movement and vice versa. The first and second modules are connected to a first and a second power inverters, respectively. The first and second inverters are connected in series and the first and the second direct voltage sources are connected in series to generate an overall direct voltage to which the inverters are connected. The power inverters each has one voltage measuring device for measuring the power inverter direct voltage present at the respective inverter and a power inverter control device for controlling the operation of the inverters in accordance with the power inverter direct voltage.

This three-phase AC motor drive device is provided with: a load; an inverter device 1 for driving the load; an MCOK_A_4 connected between the inverter device 1 and the load and electrically connecting or disconnecting the inverter device 1 to or from the load; a voltage detector 21a having terminals respectively connected to the circuits of at least two phases to detect the voltages between the three phases; and a current detector 11 for detecting the currents of the three phases. In the connection from the inverter device 1 to the load, the inverter device 1, the MCOK_A_4, the voltage detector 21a, the current detector 11, and the load are aligned in this order.

This three-phase AC motor drive device is provided with: a load; an inverter device 1 for driving the load; an MCOK_A_4 connected between the inverter device 1 and the load and electrically connecting or disconnecting the inverter device 1 to or from the load; a voltage detector 21a having terminals respectively connected to the circuits of at least two phases to detect the voltages between the three phases; and a current detector 11 for detecting the currents of the three phases. In the connection from the inverter device 1 to the load, the inverter device 1, the MCOK_A_4, the voltage detector 21a, the current detector 11, and the load are aligned in this order.

An electric system has an electrical energy source connected to an electrical energy sink by at least one feeding line. Each feeding line (8) is in at least one position therealong between said source and said sink provided with an arrangement configured to interrupt arcing in the feeding line would such arcing reach this position. The arrangement has a temperature dependent member which upon an increase of the temperature thereof above a predetermined level activates an irreversible movement of movable means (24) which by this movement cuts off the arc (a) and/or removes hot ionized gases (28) and by that prevents the arcing to continue in the feeding line past the arrangement.

A power conversion apparatus includes a filter capacitor, a contactor to electrically connect the filter capacitor to a power source or electrically disconnect the filter capacitor from the power source, and a failure determiner to determine whether a failure occurs in the contactor. When the contactor is kept closed during a determination period since closing of the contactor and a reduction in the voltage in the filter capacitor during the determination period is greater than or equal to a reference value, the failure determiner determines occurrence of a failure in the contactor.

An electric vehicle control device includes a first inverter controlling a first group defined by induction motors, and a second inverter controlling a second group defined by induction motors. The first inverter and the induction motors of the first group are connected to each other by a first conductor. The second inverter and the induction motors of the second group are connected by a second conductor. A first length is equal to or less than three times the average value of a second length and a third length. The first length is an inter-center distance between the first conductor and the second conductor, the second length is the maximum length of a conductor portion of the first conductor in the cross section of the first conductor, and the third length is the maximum length of a conductor portion of the second conductor in the cross section of the second conductor.

An apparatus comprises a power electronic energy conversion system comprising a first energy storage device configured to store DC energy and a first voltage converter configured to convert a second voltage from a remote power supply into a first charging voltage configured to charge the first energy storage device. The apparatus also includes a first controller configured to control the first voltage converter to convert the second voltage into the first charging voltage and to provide the first charging voltage to the first energy storage device during a charging mode of operation and communicate with a second controller located remotely from the power electronic energy conversion system to cause a second charging voltage to be provided to the first energy storage device during the charging mode of operation to rapidly charge the first energy storage device.

An apparatus comprises a power electronic energy conversion system comprising a first energy storage device configured to store DC energy and a first voltage converter configured to convert a second voltage from a remote power supply into a first charging voltage configured to charge the first energy storage device. The apparatus also includes a first controller configured to control the first voltage converter to convert the second voltage into the first charging voltage and to provide the first charging voltage to the first energy storage device during a charging mode of operation and communicate with a second controller located remotely from the power electronic energy conversion system to cause a second charging voltage to be provided to the first energy storage device during the charging mode of operation to rapidly charge the first energy storage device.

A circuit system for a railroad vehicle according to an embodiment includes a power conversion unit, a first converter, a second converter, a power storage unit, and a control unit. The power conversion unit converts power supplied from an overhead wire into power for driving a motor for running mounted on a railroad vehicle. The first converter converts power supplied from the overhead wire into DC power. The second converter converts power output from the first converter into power for driving a load mounted on the railroad vehicle. The power storage unit is electrically connected to an input side of the second converter. The control unit inputs regenerative power output from the power conversion unit to the first converter and inputs power output from the first converter to the power storage unit in a case where it is determined that the railroad vehicle is being regenerated.

System and method configured to determine a direction of movement of a vehicle in response to a brake being released or in response to initiating movement of the vehicle from a stopped position along a route. The direction of movement is determined based on a selected travel direction of the vehicle, a grade of the route, and at least one of applied tractive efforts or applied braking efforts.