Hitachi Industrial Equipment Systems Co., Ltd.

Hitachi, Ltd.

Naoki Takata

Satoshi Ibori

Masahiro Hiraga

Masayuki Hirota

Tomoya Kamezawa

Kinya Nakatsu

Daisuke Matsumoto

Fumihiro Sato

Mutsuo Tokashiki

Kazushige Hotta

Keisuke Tanabe

Hidenori Sugino

Akiko Ishii

Shigetoshi Yagihara

Kinya Hitachi Ltd Nakatsu

With the aim of improving the reliability of a power conversion device for driving a motor, this power conversion device is provided with a rectifying portion for rectifying an AC voltage and outputting a DC voltage, a smoothing capacitor for smoothing the DC voltage, an inverter portion into which the DC voltage is input and which outputs AC power, an inverter drive portion for outputting a gate signal to the inverter portion, a regenerative braking portion connected in parallel with the smoothing capacitor, a regenerative braking drive portion for outputting a gate signal to the regenerative braking portion, a control portion for outputting drive signals to the inverter drive portion and the regenerative braking drive portion, a regenerative braking overcurrent detecting portion for outputting an overcurrent detection signal if the current flowing through the regenerative braking portion exceeds a determination value, and a latch portion into which the overcurrent detection signal output from the regenerative braking overcurrent detecting portion is input and which outputs a gate output interruption signal to the control portion, wherein switching elements of the inverter portion and the regenerative braking portion stop in an off state when the regenerative braking overcurrent detection portion detects an overcurrent.

Power conversion device

A temperature detection method for a semiconductor device and a power conversion apparatus are disclosed. A temperature detection device is used to detect the temperature for thermal protection of a power semiconductor device. The temperature detection device is placed in the proximity of a component having the power semiconductor device packaged therein, and either an emitter terminal or a collector terminal of the power semiconductor device. Since the temperature detection device is mounted on a circuit board, it does not require insulation from a cooling fin on which the power semiconductor device is mounted and lead wires can be eliminated.

Temperature detection method of semiconductor device and power conversion apparatus

The invention provides a technique and a product in which for a frequency converter supplying electric power to, for example, a motor, a downsizing, lightening or the like of the frequency converter is realized while providing a filter apparatus reducing electromagnetic noises and the like. The filter apparatus reducing electromagnetic noises and the like is provided near a main circuit terminal board of the frequency converter, and the filter apparatus is connected directly to a main circuit terminal as a wiring drawing portion of the frequency converter. Part of a housing of the frequency converter and part of a filter housing are fitted to each other to fix the filter housing to the frequency converter.

Filter apparatus and frequency converter to which the filter apparatus is connected

A power conversion apparatus is disclosed. In the case where a coil is arranged in a power module, the circuit system between the ends of the coil in the power module, regardless of where the coil is located, is structurally isolated and insulated from each other. This isolation and insulation prevents the capacitance from being created across the coil, and the coil can exhibits the effect as a filter, thereby improving the characteristics of a noise filter.

Power conversion apparatus including a rectifier circuit and an inverter circuit

An electric circuit module comprising: an electric device comprising an electric circuit to serve for passage and interruption of electric current, a packing material packing the electric circuit and a plurality of wiring members to electrically connect the electric circuit with an external circuit; and a heat sink to radiate heat from the electric device. The electric circuit module includes a fixture to fix the heat sink and the electric device together so that a heat radiating surface of the electric device comes into contact with the heat sink. The fixture is formed with a recess to accommodate therein a part of the electric device so that the heat radiating surface of the electric device is exposed from the fixture. When the electric device is fixed to the heat sink by the fixture, the heat radiating surface comes into contact with the heat sink.

Electric circuit module

An inverter apparatus having at least an inverting portion for inverting a DC electric power into an AC electric power, wherein the inverting portion includes: high speed switching elements; driver circuits for driving the high speed switching element; and a controller portion for outputting logical driving ON/OFF signals for controlling the AC electric power to the driver circuit, wherein the controller portion controls so that the minimal time of the OFF signal of the logical driving ON/OFF signals for the high speed switching element comes to be equal or greater than a predetermined value, thereby protecting the high speed switching elements constructing the inverter apparatus from breakdown due to a the short OFF pulse.

Growing community of inventors

Narashino, Japan

Naoki Takata