Mitsubishi Electric Corporation

Toshihiko Miyauchi

Mitsuru Tsukima

Norio Takeuchi

Makoto Kanemaru

Tomoko Takasuka

Mamoru Togami

Takuya Ohkubo

Koki Nagayama

An abnormality diagnosis device performs determination for at least one of abnormality of an electric motor driven by an inverter driven at a predetermined operation frequency and abnormality of a motive power transmission mechanism which transmits motive power from the electric motor to a load, wherein spectrum peaks extracted through FFT analysis of detected current of the electric motor are analyzed, and frequencies of spectrum peaks due to noise of the inverter are acquired in advance using the operation frequency and the frequencies of sideband waves with respect to the operation frequency. In abnormality diagnosis, abnormality determination is performed after spectrum peaks due to noise of the inverter are extracted from spectrum peaks extracted through FFT analysis of detected current of the electric motor.

Abnormality diagnosis device and abnormality diagnosis method

The invention includes an output circuit that outputs an operation signal to a direct current breaker that interrupts a direct current main circuit, and a processor that samples, at predetermined time intervals, digital data wherein a value detected by a direct current transformer that detects a current of the direct current main circuit is measured as an input current, calculates a computed measurement value to be output to a display circuit, and outputs control information for executing a protection process using measurement value sampling data obtained by the sampling to the output circuit, and executes a protection process of the direct current main circuit at every sampling.

Digital relay

The power transmission mechanism abnormality diagnostic device includes a monitoring diagnosis unit for performing determination as to abnormality of a power transmission mechanism, and a current detector connected to a power supply of an electric motor, wherein the monitoring diagnosis unit includes an analysis unit for analyzing current transmitted from the current detector and an abnormality determination unit for performing determination as to abnormality of the power transmission mechanism on the basis of a result of analysis by the analysis unit.

Abnormality diagnostic device for power transmission mechanism and abnormality diagnostic method for power transmission mechanism

Growing community of inventors

Tokyo, Japan

Toshihiko Miyauchi