Daikin Industries, Ltd.

Yoshitsugu Koyama

Hirotaka Doi

Reiji Kawashima

Masahiro Yamamoto

Hiroshi Doumae

Sumio Kagimura

Masaki Kono

Keito Kotera

Mitsuhiro Tanaka

Taichi Koshiji

Hiroshi Fuchikami

Michiya Takezoe

Takahiro Matsui

Takuji Koyama

Rei Kondou

Makoto Takayanagi

Kodai Okuzono

Yukio Akita

A noise reduction circuit includes: noise canceler circuitry configured to inject a compensation current into a power line and ground to reduce a common mode noise current that flows through the power line and the ground into a commercial power supply from a power converter with a switching element connected to the commercial power supply; and overcurrent inhibitor circuitry provided on a compensation current path through which the compensation current flows, the overcurrent inhibitor circuitry being configured to inhibit application of an overcurrent to the noise canceler circuitry.

Noise reduction circuit, power conversion device, and refrigeration apparatus

A heat exchange unit includes a heat exchanger, a structure supporting the heat exchanger, an insulating member electrically insulating the heat exchanger from the structure, a compressor electrically connected to the heat exchanger and the structure, and a connection member attached to the heat exchanger. The connection member electrically connects the heat exchanger and the structure. The connection member is provided separately from a first conductive path that electrically connects the compressor and the heat exchanger, and a second conductive path that electrically connects the compressor and the structure.

Heat exchange unit

An inverter device uses an inverter to convert DC voltage supplied from a rectifying component to AC voltage and applies the AC voltage to an inductive load. The inverter device includes a shunt resistor provided on a direct-current link interconnecting the rectifying component and the inverter, a first terminal passing current to the shunt resistor, a second terminal to which the current from the shunt resistor flows, and a printed board having a conductive pattern with first and second conductive pattern components joining the shunt resistor and the first and second terminals, respectively. The first conductive pattern component includes a first central region connecting right and left side ends of the shunt resistor to right and left side ends of the first terminal, and first right and left side protruding regions. A ratio of areas of the first left and right side protruding regions is 0.6 to 1.6.

Inverter device having shunt resistor and printed board with conductive pattern component joining shunt resistor and terminal

For an electronic circuit apparatus including a shunt resistor, provided is a measure for improving the heat dissipation performance of the shunt resistor. The shunt resistor includes electrodes at both ends. One of the two electrodes is connected to a surface-mounting pattern on which the shunt resistor is surface-mounted. A current-generating-side pattern and a current-receiving-side pattern are arranged separately from the surface-mounting pattern. The current-generating-side pattern and the surface-mounting pattern are connected together via a connection member which creates a space between itself and a substrate.

Electronic circuit apparatus

A refrigeration apparatus includes: an electrical circuit () including a power device (); a refrigerant jacket () which is thermally connected to the power device (), and in which a refrigerant for a refrigeration cycle flows; a refrigerant pipe () which carries the refrigerant flowing in the refrigerant jacket (), and forms a current path () for grounding the refrigerant jacket (); and a magnetic body () which is attached to the current path (), and generates a predetermined impedance in the current path ().

Refrigeration apparatus with a magnetically shielded refrigerant pipe

A power converter is provided with a rectifying circuit, an inverter circuit, and a common mode filter including a common mode choke coil and a capacitor. The switching frequency of a PWM rectifying circuit is set at three times the switching frequency of a PWM inverter. Alternatively, the resonance frequency of the common mode filter is set at twice the carrier frequency of the rectifying circuit or the PWM inverter circuit or more.

Power converter

Growing community of inventors

Shiga, Japan

Yoshitsugu Koyama