A propulsion system includes plural inverters configured to be onboard a vehicle and to convert direct current into an alternating current, and plural motors configured to receive the alternating current from the inverters. The motors also are configured to be operably coupled with axles of the vehicle to rotate the axles. The inverters are configured to be coupled with and control the motors that rotate non-neighboring axles of the axles in the vehicle.

The invention relates to a bogie (10) for a high-speed railway vehicle, comprising: a bogie chassis, at least one wheel (20) mounted rotating on the chassis by means of an axle (18) and a primary suspension system (22), at least one motor (24), for each motor (24), at least one gearbox (26) able to mechanically link the motor (24) and the axle (18). Each motor (24) is rigidly fastened to the chassis (12).

The invention relates to a bogie (10) for a high-speed railway vehicle, comprising: a bogie chassis, at least one wheel (20) mounted rotating on the chassis by means of an axle (18) and a primary suspension system (22), at least one motor (24), for each motor (24), at least one gearbox (26) able to mechanically link the motor (24) and the axle (18). Each motor (24) is rigidly fastened to the chassis (12).

A semiconductor device according to an embodiment includes a silicon carbide layer, a silicon oxide layer including carbon, the silicon oxide layer including single bonds between carbon atoms which are at least a part of the carbon, the number of the single bonds between carbon atoms being greater than the number of double bonds between carbon atoms which are at least a part of the carbon, and a region provided between the silicon carbide layer and the silicon oxide layer, the region including at least one element from the group consisting of nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi), scandium (Sc), yttrium (Y), and lanthanoids (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu).

A semiconductor device of an embodiment includes: a silicon carbide layer including a first silicon carbide region of n-type containing one metal element selected from a group consisting of nickel (Ni), palladium (Pd), platinum (Pt), and chromium (Cr) and a second silicon carbide region of p-type containing the metal element; and a metal layer electrically connected to the first silicon carbide region and the second silicon carbide region. Among the metal elements contained in the first silicon carbide region, a proportion of the metal element positioned at a carbon site is higher than a proportion of the metal element positioned at an interstitial position. Among the metal elements contained in the second silicon carbide region, a proportion of the metal element positioned at an interstitial position is higher than a proportion of the metal element positioned at a carbon site.

A connection structure includes: a circuit breaker connected to a power cable through which high-voltage power is supplied; a high-voltage device box accommodating the circuit breaker; a main transformer configured to transform a voltage of the high-voltage power and provided under the floor of the car; a first connector device electrically connected to the circuit breaker and provided at a dividing wall of the high-voltage device box; a second connector device electrically connected to the main transformer and provided at a dividing wall of the main transformer; and a high-voltage cable covered with an insulating coating and having both end portions to which cable connector portions are respectively attached, wherein the high-voltage cable connects the first connector device and the second connector device in such a manner that the cable connector portions respectively fit and are connected to the first connector device and the second connector device.

A connection structure includes: a circuit breaker connected to a power cable through which high-voltage power is supplied; a high-voltage device box accommodating the circuit breaker; a main transformer configured to transform a voltage of the high-voltage power and provided under the floor of the car; a first connector device electrically connected to the circuit breaker and provided at a dividing wall of the high-voltage device box; a second connector device electrically connected to the main transformer and provided at a dividing wall of the main transformer; and a high-voltage cable covered with an insulating coating and having both end portions to which cable connector portions are respectively attached, wherein the high-voltage cable connects the first connector device and the second connector device in such a manner that the cable connector portions respectively fit and are connected to the first connector device and the second connector device.

An interface breakdown-proof locomotive roof composite insulator. The composite insulator comprises: a support body; and at least five shed groups arranged side by side along the axial direction that are provided around the sidewall of the support body, the at least five shed groups includes: at least four shed groups located on the upper end with each group including a large shed and a small shed; and at least one shed group located on the undermost end with each group including two small sheds. For such a shed structure, it is favorable to tolerate impulse voltage, and it is difficult for the interface to be broken down; the electric field on the interface even does not exceed 3 kV/mm, and even if a gas exists on the interface, it will not break through the interface.

An interface breakdown-proof locomotive roof composite insulator. The composite insulator comprises: a support body; and at least five shed groups arranged side by side along the axial direction that are provided around the sidewall of the support body, the at least five shed groups includes: at least four shed groups located on the upper end with each group including a large shed and a small shed; and at least one shed group located on the undermost end with each group including two small sheds. For such a shed structure, it is favorable to tolerate impulse voltage, and it is difficult for the interface to be broken down; the electric field on the interface even does not exceed 3 kV/mm, and even if a gas exists on the interface, it will not break through the interface.

A failure sign determining device includes an acquirer to acquire pieces of sensor data based on respective values measured by multiple sensors, an FFT processor to execute fast Fourier transform on each of the pieces of sensor data and thereby generate a piece of frequency spectrum data, and a determiner to determine the existence of a failure sign on the basis of comparison between the piece of frequency spectrum data and a spectrum range defined for the sensor. The determiner, only when determining that a failure sign exists, transmits at least either of the piece of frequency spectrum data and the piece of sensor data to an analysis apparatus.