Mitsubishi Electric Corporation

Yasutaka Imamura

Yohei Mitsui

Hisanori Yamasaki

Takeshi Horiguchi

Junichi Nakashima

Yasushige Mukunoki

Yuta Matsumoto

A semiconductor device includes a power switching element and a drive device to drive the power switching element. The drive device includes a voltage source, a switching element, a capacitor connected in parallel to the voltage source with the switching element being interposed, a switching element provided between the capacitor and a gate terminal of the power switching element, a first comparison device to output a result of comparison between a voltage of the capacitor and a reference value VQR, a second comparison device to output a result of comparison between a gate voltage of the power switching element and a reference value VR, and a short-circuit determination unit that makes determination as to a short circuit of the power switching element based on an output signal from the first comparison device and an output signal from the second comparison device.

Drive device to drive semiconductor element, semiconductor device, and power conversion device

A semiconductor drive device includes a drive circuit that drives a semiconductor switching element, a passive element connected to a gate of the semiconductor switching element to prevent a gate current of the semiconductor switching element, a switching element connected in series to the passive element, a control circuit that controls the switching element, and a temperature detection circuit that detects a temperature of the semiconductor switching element. The control circuit controls the switching element such that when the temperature detected by the temperature detection circuit is high, the gate current is prevented more than when the temperature is low.

Semiconductor drive device, semiconductor device, and power conversion device

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.

Monitoring device for electric vehicles

A primary circuit and a secondary circuit each have a switching element, each operate as a power conversion circuit while the switching element is activated, and each operate as a rectifier circuit while the switching element is deactivated. While a generator provided at the primary side of a first power conversion device is stopped, a controller activates the switching element of the secondary circuit and deactivates the switching element of the primary circuit. Accordingly, the first power conversion device converts electric power input from the secondary side and supplies electric power for causing the generator to operate. While the generator is operated, the controller activates the switching element of the primary circuit and deactivates the switching element of the secondary circuit such that the first power conversion device converts electric power supplied from the generator and outputs the converted electric power to the secondary side.

Growing community of inventors

Tokyo, Japan

Yasutaka Imamura