Hitachi, Ltd.

Hitachi Industrial Equipment Systems Co., Ltd.

Tetsuji Kato

Yoshitaka Iwaji

Kenji Ikeda

Kohji Maki

Minori Nagata

Tomoaki Hiruta

Munetoshi Unuma

Genzo Iwaki

Yoshitaka Atarshi

A failure diagnosis system flexibly responds to a change in a diagnosis target by using a difference in measurement data before and after maintenance in predictive failure diagnosis. A pre-maintenance data DB stores measurement data before maintenance, and a post-maintenance data DB stores measurement data after maintenance. A feature detection algorithm group DB is provided where a plurality of feature detection algorithms are stored. A first feature is detected based on the measurement data by using each of the plurality of feature detection algorithms read from the feature detection algorithm group DB. An algorithm search unit selects one of the plurality of algorithms based on the feature thus detected. A second feature is detected from the measurement data by using the feature detection algorithm, and a sign predictive of failure of diagnosis of target equipment is diagnosed using the detected second feature.

Failure diagnosis system

A rotor diagnostic apparatus includes a parameter selection part that calculates evaluation values indicating how much sensor values of a rotor at a given time point deviate from a reference value at which the rotor is known to be in a normal state, the given time point being after the rotor is known to be in the normal state and before the rotor is to be diagnosed, and selects a plurality of parameters to be used for abnormality diagnosis of the rotor from the sensor values based on the calculated evaluation values. A diagnosis part outputs an abnormality value which is indicative of how abnormal the rotor is and which is obtained based on a distance, in a multidimensional space having the selected parameters as coordinate axes, between a figure represented by sensor values in the normal state and a figure represented by sensor values targeted for diagnosis.

Rotor diagnostic apparatus, rotor diagnostic method, and rotor diagnostic program

A power conversion device according to the present invention is connected to a rotating machine comprising an armature coil and supplies and receives power. The power conversion device has a function for: collectively applying voltage pulses to the armature coil or coils for one or more specific phases of the rotating machine, sampling the current values of the specific phases from the start of the rising or falling of the voltage pulses until a designated delay time, detecting variation in the capacitance of an insulation member of the armature coils of the specific phases of the rotating machine from variation from a normal state of the current values, and diagnosing insulation degradation.

Power conversion device, rotating machine system using same, and diagnosis method for same

Provided are a non-contact voltage measurement device and diagnosis system capable of acquiring the voltage of an electric wire without disconnecting the wire. The non-contact voltage measurement device () includes: a cylindrical fixing part () for holding an electric wire () by clipping the same from both sides; a first electrode () and a second electrode () provided on the inner peripheral surface of the electric-wire-holding side of the fixing part () so as to be separated by a distance (D); a first measurement capacitor (C) and a voltage division capacitor (C) connected to the first electrode (); a second measurement capacitor (C') connected to the second electrode (); a terminal () for measuring the voltage (V) applied to the first measurement capacitor (C); and a terminal () for measuring the voltage (V) applied to the second measurement capacitor (C&#x2032;).

Non-contact voltage measurement device and diagnosis system

An operation mode specifying unit specifies an operation mode of a machine by comparing time-series data of an amplitude and a frequency of measurement data obtained from a sensor with definition data of the operation mode of the machine created in advance by an operation mode data creation unit. In addition, an abnormality diagnosis unit performs processing of cluster analysis for the measurement data obtained from the sensor or the like, and diagnoses abnormality of the machine according to diagnosis procedure information that is set in advance depending on the set operation mode and an abnormality mode of the machine.

Machine diagnostic apparatus and machine diagnostic method

A rotary machine diagnostic system includes: a current measurement unit for measuring a leakage current of a rotary machine; a voltage measurement unit for measuring a voltage of the rotary machine corresponding to the flowing leakage current; and a data processing unit. The data processing unit has a function of performing transient response analysis on a predetermined equivalent circuit model, which is equivalent to a leakage current path of the rotary machine, using current data and voltage data having a predetermined time width which are respectively measured at predetermined time intervals by the current measurement unit and the voltage measurement unit, and a function of extracting parameters of the equivalent circuit of the leakage current path.

Rotary machine diagnostic system

An object is to conduct an insulation degradation diagnosis with a simple configuration. An insulation diagnostic system includes a current detection sensorthat is installed, for a coilof at least one phase of a &#x394; connection type rotating machine in which current flows in the reverse direction at a winding start position and a winding end position, such that the current detection sensorsurrounds a current path flowing into a leader line at the winding start of the coiland a current path flowing out from a leader line at the winding end of the coil

Insulation diagnostic system or rotating machine

An anomaly diagnosis system is provided that includes: a current-value obtaining partthat obtains a value of an AC current inputted to or outputted from a device to be diagnosed; a frequency analyzing partthat converts the current values obtained at intervals into a frequency spectrum which correlates a current intensity with a frequency; an anomaly-judging-value calculating partthat calculates at intervals a frequency width of the frequency spectrum at a current intensity 'As' satisfying As=m&#xd7;At (0&#x3c;m&#x3c;1), where 'At' is a peak current intensity associated with an analysis frequency which is an integer multiple of a frequency of the AC current; and a judging partthat judges whether the frequency width is wider than that in a normal condition and, if it holds true, judges that the device is in an anomalous condition.

Growing community of inventors

Tokyo, Japan

Tetsuji Kato