ABNORMALITY DETECTION DEVICE, METHOD AND PROGRAM

• Main Authors: AOKI TOSHIO, TAGUCHI YASUNORI, TAKADO NAOYUKI, TERAKADO YUSUKE, NAKATA KOTA, KATO YUICHI, MIYAKE RYOTA, NAITO SUSUMU, TOMINAGA MASAYA
• Format: Patent
• Language: English; Japanese
• Published: 27.03.2024
• Subjects: CONTROL OR REGULATING SYSTEMS IN GENERAL; CONTROLLING; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS ORELEMENTS; PHYSICS; REGULATING

To provide an abnormality detection device that achieves both an early detection of an abnormality and a suppression of an erroneous detection.SOLUTION: An abnormality detection device comprises a prediction unit, a temporary detection unit, a feature amount calculating unit, a second threshold value setting unit, and a detection unit. The prediction unit generates a prediction value of a monitoring target time based on a first function that outputs prediction values of measurement values when inputting the measurement values of a plurality of sensors installed in a monitoring object system. The temporary detection unit temporarily detects that a deviation between the measurement value and the prediction value exceeds a first threshold value. The second threshold value setting unit sets a second threshold value based on a second function that outputs a second threshold value when a feature amount related to a temporal change in the measurement value and the feature amount are input. The detection unit detects an abnormality or a sign of the abnormality in the monitoring object system to generate a detection signal related to the detection result by determining whether a continuous frequency of a temporary detection at a monitoring target time is equal to or greater than the second threshold value.SELECTED DRAWING: Figure 1 【課題】異常の早期検知と誤検知の抑制を両立する異常検知装置を提供する。【解決手段】異常検知装置は、予測部と、仮検知部と、特徴量算出部と、第２閾値設定部と、検知部と、を備える。予測部は、監視対象システムに設置された複数のセンサの測定値を入力すると前記測定値の予測値を出力する第１関数に基づいて、監視対象時刻の予測値を生成する。仮検知部は、前記測定値と前記予測値との偏差が前記第１閾値を超えたことを仮検知する。第２閾値設定部は、前記測定値の時間変化に関する特徴量と、前記特徴量を入力すると第２閾値を出力する第２関数に基づいて、第２閾値を設定する。検知部は、監視対象時刻における前記仮検知の連続回数が前記第２閾値以上であるか否かを判定することにより前記監視対象システムの異常または当該異常の予兆を検知し、当該検知結果に関する検知信号を生成する。【選択図】図１