A monitoring device for an electric vehicle to monitor a blower for cooling a device installed in an electric vehicle includes: a dq-component separation unit that separates an instantaneous value of a motor current that flows to a motor of the blower into a d-axis current component and a q-axis current component; a mechanical-angle rotation-frequency component extraction unit that extracts a mechanical-angle rotation frequency component from an instantaneous value of the q-axis current component, the mechanical-angle rotation frequency component being a rotation frequency component where a rotation angle of the motor is expressed in a mechanical angle; and an abnormality determination unit that determines whether or not the blower is abnormal on the basis of magnitude of the mechanical-angle rotation frequency component.

This semiconductor device according to an embodiment includes: a silicon carbide layer; a gate electrode; a silicon oxide layer between the silicon carbide layer and the gate electrode; and a region between the silicon carbide layer and the silicon oxide layer and having a nitrogen concentration not less than 1×10.sup.21 cm.sup.−3. A nitrogen concentration distribution in the silicon carbide layer, the silicon oxide layer, and the region has its peak in the region, and a state density Z.sub.1/2 in a portion is not more than 1×10.sup.11 cm.sup.−3. The portion is within 100 nm from the silicon oxide layer toward the silicon carbide layer. A nitrogen concentration and a carbon concentration in a position 1 nm from the peak toward the silicon oxide layer is not more than 1×10.sup.18 cm.sup.−3, and a nitrogen concentration in a position 1 nm from the peak toward the silicon carbide layer is not more than 1×10.sup.18 cm.sup.−3.

Methods and systems are provided for operating an engine having a plurality of cylinders that utilize oil for lubrication purposes. In one embodiment, a method for the engine may include determining if one or more conditions have been met for port heating based on one or more operating conditions of the engine, continuing current operation if the one or more conditions for port heating have not been met, and determining a souping level of the engine if the one or more conditions for port heating have been met and subsequently running port heating on a set of cylinders of the engine based on the souping level of the engine and/or the one or more conditions for port heating. The engine may be a non-EGR engine and/or a high speed diesel engine. Each cylinder of the set of cylinders may have at least one port.

Methods and systems are provided for operating an engine having a plurality of cylinders that utilize oil for lubrication purposes. In one embodiment, a method for the engine may include determining if one or more conditions have been met for port heating based on one or more operating conditions of the engine, continuing current operation if the one or more conditions for port heating have not been met, and determining a souping level of the engine if the one or more conditions for port heating have been met and subsequently running port heating on a set of cylinders of the engine based on the souping level of the engine and/or the one or more conditions for port heating. The engine may be a non-EGR engine and/or a high speed diesel engine. Each cylinder of the set of cylinders may have at least one port.

This semiconductor device according to an embodiment includes: a silicon carbide layer; a gate electrode; a silicon oxide layer between the silicon carbide layer and the gate electrode; and a region between the silicon carbide layer and the silicon oxide layer and having a nitrogen concentration not less than 1×10.sup.21cm.sup.−3. A nitrogen concentration distribution in the silicon carbide layer, the silicon oxide layer, and the region has its peak in the region, and a state density Z.sub.1/2 in a portion is not more than 1×10.sup.11cm.sup.−3. The portion is within 100 nm from the silicon oxide layer toward the silicon carbide layer. A nitrogen concentration and a carbon concentration in a position 1 nm from the peak toward the silicon oxide layer is not more than 1×10.sup.18cm.sup.−3, and a nitrogen concentration in a position 1 nm from the peak toward the silicon carbide layer is not more than 1×10.sup.18cm.sup.−3.

The present disclosure generally relates to systems and methods of increasing functional safety of locomotives. In exemplary embodiments, a locomotive functional safety system is configured to: receive one or more manual control commands from a locomotive control stand and/or a user interface onboard a locomotive; determine whether the one or more manual control commands pass or satisfy one or more predetermined criteria; if the one or more manual control commands pass or satisfy the one or more predetermined criteria, approve the one or more manual control commands and allow the one or more manual control commands to be relayed onward and/or acted upon; and if the one or more manual control commands do not pass or satisfy the one or more predetermined criteria, disapprove the one or more manual control commands and disallow the one or more manual control commands to be relayed onward and/or acted upon.

A voltage control method. A train traveling speed can be acquired; a target transformation ratio corresponding to the train traveling speed is determined according to correspondences between train traveling speeds and transformation ratios, the transformation ratio being a ratio of an input voltage to an output voltage; an input voltage is then transformed according to the target transformation ratio to obtain an output voltage, the output voltage being used for driving a train to travel. The correspondences between train traveling speeds and transformation ratios are obtained according to correspondences between train traveling speeds and train traction forces at different transformation ratios. By means of the method, the most suitable transformation ratio can be provided according to a traveling speed of a maglev train, thereby increasing the traction force of the maglev train and improving running efficiency.

A voltage control method. A train traveling speed can be acquired; a target transformation ratio corresponding to the train traveling speed is determined according to correspondences between train traveling speeds and transformation ratios, the transformation ratio being a ratio of an input voltage to an output voltage; an input voltage is then transformed according to the target transformation ratio to obtain an output voltage, the output voltage being used for driving a train to travel. The correspondences between train traveling speeds and transformation ratios are obtained according to correspondences between train traveling speeds and train traction forces at different transformation ratios. By means of the method, the most suitable transformation ratio can be provided according to a traveling speed of a maglev train, thereby increasing the traction force of the maglev train and improving running efficiency.

According to an embodiment, a railway-vehicle power conversion apparatus includes: a switching element; a capacitor connected to the switching element; and a gate substrate that supplies a drive signal to the switching element, in which the capacitor is held by a capacitor holding frame, and the gate substrate is attached and secured to the capacitor.

According to an embodiment, a railway-vehicle power conversion apparatus includes: a switching element; a capacitor connected to the switching element; and a gate substrate that supplies a drive signal to the switching element, in which the capacitor is held by a capacitor holding frame, and the gate substrate is attached and secured to the capacitor.