Mitsubishi Electric Corporation

Koji Rikukawa

Jun Someya

Kazuo Maeda

Kazuhiro Ito

Kazunori Sakanobe

Shigeo Takata

Kenji Iwazaki

Takayuki Tsuji

Mamoru Kamikura

Katsuhiro Hirose

A power conversion device supplies power to a load. The power conversion device includes a power conversion unit, a control unit, a noise suppression unit, and an error detection unit. The power conversion unit receives power from a first power source. The control unit controls the power conversion unit. The noise suppression unit is connected between the first power source and the power conversion unit and outputs a noise suppression signal to suppress noise generated from the power conversion unit. When an error condition is established, the error detection unit detects an error. The error condition indicates that the error has occurred in the power conversion device or the load. The error condition includes a condition that an amount of noise generated from the power conversion unit is larger than a reference value.

Power conversion device and air conditioner

Provided is a communication relay apparatus configured to relay communication between a plurality of segments of a network by a plurality of communication devices including an indoor unit and an outdoor unit connected to one another via the network, the communication relay apparatus including a relay setting unit configured to set a first mode value corresponding to processing of relaying all frames and a second mode value corresponding to processing of relaying a frame on the basis of a destination address of the frame, and a relay determination unit configured to perform processing of relaying the frame in an operation mode corresponding to a relay mode value set by the relay setting unit.

Communication relay apparatus and air-conditioning system

A ventilation device includes an outside air heat exchanger disposed between a total heat exchanger and an outside air port, a return air heat exchanger disposed between the total heat exchanger and a return air port, and a supply air heat exchanger disposed between the total heat exchanger and a supply air port. A compressor, a flow switching device, the outside air heat exchanger, an outside air expansion device, and the return air heat exchanger are sequentially connected by pipes, the supply air heat exchanger and a supply air expansion device which are connected in series by pipes are connected in parallel to the outside air heat exchanger and the outside air expansion device by pipes, thereby forming a refrigerant circuit in which refrigerant is circulated.

Ventilation device

A transmission relaying apparatus includes a signal receiving unit receiving a signal, transmitted from a transmission path, as a received signal; an abnormality detection unit detecting whether abnormality occurs in the received signal; and a threshold setting unit setting a preset threshold to be used for detection of abnormality by the abnormality detection unit. The threshold setting unit includes a peak value detection unit detecting a peak value of the signal level of the test signal received as the received signal by the signal receiving unit, when a test signal is output from a communication diagnostic apparatus; a threshold obtaining unit obtaining the preset threshold based on the peak value detected by the peak value detection unit; and a threshold holding unit storing the preset threshold, obtained by the threshold obtaining unit, as a preset threshold to be used by the abnormality detection unit.

Growing community of inventors

Tokyo, Japan

Koji Rikukawa