Abstract: A pipeline inspection system may include a cable that may be configured to be directed into a conduit. The pipeline inspection system may further include a camera disposed on a distal end of the cable and operable to capture an image. The pipeline inspection system may further include a monitor including a display configured to display an image. The pipeline inspection system may further include an electronic processor that may be configured to receive a user input indicating a characteristic of the conduit. The electronic processor may be further configured to determine an image setting of the display based on the characteristic of the conduit. The electronic processor may be further configured to control the monitor to display the image on the display according to the image setting.

Abstract: A method is provided for determining the geometry of a metallic object, with in particular one or more real, examined defects, with a reference data set of the object generated on the basis of at least one measurement by at least one non-destructive measuring method, preferably comprising an at least partial representation of the object on or by an at least three-dimensional object grid by means of a computer unit. A classification of anomaly-free areas and anomaly-affected areas of the object is performed on the basis of at least parts of the at least one reference data set.

Abstract: A method for estimating the movement of an object moving in an ambient magnetic field. The method includes acquiring by a magnetic measuring device integral with the object at least one component of the magnetic field and/or at least one i-th derivative of the magnetic field, with n+1?i?1, n?1, at the level of the magnetic measuring device. The method then estimates at least one component of the movement of the object using at least one component of the equation ?{dot over (n)}B=fn(?)·?nB+gn(?n+1B)·V, where ?nB is an n-th derivative of the magnetic field, ? is the instantaneous angular velocity, V is the instantaneous linear velocity, and fn and gn are predetermined functions.

Abstract: The apparatus is useful for monitoring integrity of casings, tubings, and other tubular strings in oil and gas wells. An apparatus for defectoscopy of downhole casings includes several units in a housing. An electromagnetic field generation unit generates excitation pulse of a specified amplitude and duration. It includes an exciter coil containing a core made a high magnetic permeability material. A pick-up sensor unit includes an integral pick-up coil and radial pick-up coils mounted around the exciter coil winding. Each pick-up coil has a U-shaped core with poles directed perpendicularly to the surveyed pipe surface and having a center line parallel to the center line of the exciter coil winding. A data control, acquisition, and processing unit includes operational amplifiers with variable amplification factors and analog-to-digital converters (ADCs) that transmit signals from the pick-up coils to software for casing defect analysis.

Abstract: Disclosed are method and apparatus for measuring material properties. Segmented field sensors have multiple sensing elements at different spatial geometries to capture field components having substantially different depths of penetration. These sensors are excited and measured on these different sensing elements to facilitate characterization of unknown material properties. This is illustrated in some embodiments using eddy current sensors to characterize materials that are frequency dispersive and/or do not produce a measurable phase shifts. Only a single scalar quantity may provide independent information from one or more of the sensing elements. Property estimation techniques, such as those using precomputed databases of sensor responses are used to estimate the unknown material properties.

Abstract: A pipeline inspection system may include a cable that may be configured to be directed into a conduit. The pipeline inspection system may further include a camera disposed on a distal end of the cable and operable to capture an image. The pipeline inspection system may further include a monitor including a display configured to display an image. The pipeline inspection system may further include an electronic processor that may be configured to receive a user input indicating a characteristic of the conduit. The electronic processor may be further configured to determine an image setting of the display based on the characteristic of the conduit. The electronic processor may be further configured to control the monitor to display the image on the display according to the image setting.

Abstract: The present disclosure provides functional test equipment for a device under test and method of testing the device under test. The functional test equipment includes a first power supply, a second power supply and a relay system. The first power supply is configured to generate a first supply voltage. The second power supply is configured to generate a second supply voltage different from the first supply voltage. The relay system is configured to electrically couple the first power supply or the second power supply to the device under test, wherein the first supply voltage is applied to the device under test for a first duration and the second supply voltage is applied to the device under test for a second duration less than the first duration.

Abstract: Data is received that comprises a full model for a physical object having a rotating part and a stationary part. The physical object includes fields coupled between the rotating part and the stationary part. A mesh is then generated for a portion of the physical object that includes a rotating mesh and a stationary mesh. Thereafter, a partial simulation model is created based on the full model and the mesh. Coupling relationships are established for the fields between the rotating mesh and the stationary mesh in the partial simulation model. The fields are then solved based on the coupling relationship of the partial simulation model. Thereafter, fields of the full model can be recovered based on the solved fields. Related apparatus, systems, techniques and articles are also described.

Abstract: The invention involves a system and method for increasing positional accuracy of surgical systems that utilize magnetic or electromagnetic sensors to provide positional awareness to a surgeon or robot performing the surgery. The system takes advantage of electromagnetic tracking through sensors. These sensors are very accurate and repeatable, while being compact enough to not inhibit surgical procedures. The accuracy and repeatability of the sensors is <1 mm within a predetermined 6 inch×6 inch performance motion box. The system is constructed and arranged to map the distortion patterns of the sensor and, in real time, correct the distortion pattern to provide accurate location of anatomical structures for performance of a surgery.

Abstract: Disclosed are method and apparatus for measuring material properties. Segmented field sensors have multiple sensing elements at different spatial geometries to capture field components having substantially different depths of penetration. These sensors are excited and measured on these different sensing elements to facilitate characterization of unknown material properties. This is illustrated in some embodiments using eddy current sensors to characterize materials that are frequency dispersive and/or do not produce a measurable phase shifts. Only a single scalar quantity may provide independent information from one or more of the sensing elements. Property estimation techniques, such as those using precomputed databases of sensor responses are used to estimate the unknown material properties.

Abstract: The magnetic flowmeter includes at least one coil and a pair of electrodes is configured to detect an electromotive force within the process fluid flow in response to the magnetic field. Measurement circuitry is coupled to the electrodes and is configured to provide an indication of the detected electromotive force. A processor is coupled to the measurement circuitry and is configured to receive the indication of the detected electromotive force. The processor is configured to obtain a sequence of indications of detected electromotive force over a time interval and to generate a plurality of sets of emf samples by selecting non-continuous indications of the detected electromotive force. Each of the sets of emf samples is processed by a signal processing engine to provide an emf sample output. The processor is configured to combine emf sample outputs from each set of emf samples to generate a process fluid flow output.

Abstract: A system includes an inspection robot having a plurality of input sensors comprising a plurality of magnetic induction sensors and configured to provide inspection data of an inspection surface, wherein the inspection data comprises electromagnetic (EM) induction data, and wherein the plurality of input sensors are distributed horizontally relative to the inspection surface; wherein at least a portion of the inspection surface comprises a ferrous substrate having a non-ferrous coating thereupon; a controller, comprising: an EM data circuit structured to interpret the EM induction data, and to determine a substrate distance value in response to the EM induction data; and a thickness processing circuit structured to determine a thickness value in response to the EM induction data, the thickness value comprising a thickness of the non-ferrous coating.

Abstract: An electrically conductive probe, such as a probe similar to those utilized in other electric leak detection systems, is positioned electrically adjacent to different regions of a wall of an underground access chamber, for detection of leaks therein. In one embodiment, the probe is positioned at an elevation and circumferential position which is sequentially adjusted so that the probe can scan regions of the wall for leaks. In another embodiment, a modified probe remains centrally located within the underground access chamber and only moved vertically. The modified probe is fitted with whiskers extending radially. The modified probe includes sectors circumferentially spaced from each other and with each whisker associated with one of the sectors. A selector switch electrically connects one sector to the electrically conductive cable. Data collected by either probe can be graphed or otherwise analyzed with regions of high conductivity correlating with leaks in the underground access chamber.

Abstract: Methods and systems for inspecting insulated equipment for corrosion under insulation are provided. The system includes an autonomous unmanned vehicle having aerial and ground locomotive capabilities. The vehicle includes an infrared detector and a pulsed eddy current sensor. In the method, infrared waves emitted from the equipment are detected along the equipment with the infrared detector. Using the infrared detector, at least one image of an inner surface of the equipment is developed based on the detected infrared waves. At least one area that is susceptible to corrosion is determined based on the at least one image. The susceptible area is inspected with the pulsed eddy current sensor, which induces an eddy current in the inner wall of the equipment. Based on a rate of the decay in strength of the eddy current, it is determined whether corrosion exists at the susceptible area using a processor configured by code.

Abstract: A vertical shaft steel wire rope cage guide sliding sleeve wear amount detection device includes flexible printed circuit (FPC) flat cable units, voltage detection circuit units, a control system, and data display equipment. Two end faces of a vertical shaft steel wire rope cage guide sliding sleeve are provided with the FPC flat cable units, the FPC flat cable units being sequentially attached to end portion surfaces of the sliding sleeve along an outer periphery of a rope hole of a steel wire rope to form an enclosure; each FPC flat cable unit is connected to one voltage detection circuit unit; a signal input end of the control system is connected with the voltage detection circuit units, and a signal output end of a control module is connected to a wireless transmission module; and the data display equipment receives data transmitted by the wireless transmission module.

Abstract: A method for detecting deterioration of a structural part includes: detecting a waveform of time domain of the structural part by a sensor disposed on the structural part; performing a conversion of time domain to frequency domain for the waveform of time domain by a processor electrically connected to the sensor so as to obtain an actual modal parameter of each of a plurality of modals related to a waveform of frequency domain of the structural part; comparing the actual modal parameter of each of the plurality of modals to modal parameter information stored in a database to determine whether a deterioration defect exists in the structural part; and determining a degree and a position of the deterioration defect when the deterioration defect exists in the structural part.

Abstract: In an embodiment of the disclosed technology, a visual output of data from a ground-penetrating radar and magnetic field measuring device is displayed on a visual medium. The display has a first exhibition of output from the ground-penetrating radar device and a second from a magnetic field measuring device, such as a very low frequency (VLF) receiver. Using an identical axis, such as an X-axis measuring time or distance, output of each device is exhibited and overlaid over one another. In this manner, one can detect (using two different methodologies and uses) the visual exhibition of both to best determine the location of a metal or electrical target.

Abstract: The invention relates to improved systems and methods for inspecting the tubes of a steam generator of a nuclear reactor that involves modeling the steam generator, comparing signals of a tube from an eddy current sensor with aspects of the model to determine whether further analysis is required, employing primary and secondary analysis processes, and producing a combined report of the primary and secondary analysis results.

Abstract: Embodiments of the present invention provide systems to detect crack-like features in pipeline welds using magnetic flux leakage data and pattern recognition. A screening process, for example, does not affect or change how survey data is recorded in survey tools; only how it is analyzed after the survey data is completed. Embodiments of the present invention can be used to screen for very narrow axial anomalies in the pipeline welds, and may also be used to predict the length of such anomalies. Embodiments of the present invention also produce a listing of the anomalies based on their relative signal characteristics.

Abstract: Faults and fault types in electric machines can be identified based on spectra associated with stator and field currents. Signals associated with such currents can be compensated for line variations, and spectral contributions for non-eccentric machines can be reduced or eliminated to permit distinguish static eccentricities from non-eccentric machine operation. One or more of a static eccentricity, a dynamic eccentricity, and a mixed eccentricity can be identified based on spectral component magnitudes at selected frequencies.

Abstract: The system utilizes electroscan equipment including a voltage source and current meter with a cable having one end grounded and one end having an electric probe thereon sized to fit within an underground pipe. The probe is able to complete an electric circuit back to ground when the probe is adjacent a defect through which electric currents can pass, thus producing varying electric current. A cable reel is provided with portions of the cable supported thereon and with a cable distance sensor coupled to the reel along with the current meter and voltage source in the form of a battery. The current meter and distance sensor transmit wireless signals to an on-site processor, such as a smartphone, for on-site data evaluation. Such unconditioned data is also transmitted to a remote location for conditioning of the data and retransmission of the conditioned data back to the on-site processor.

Abstract: Embodiments of the present invention provide computer-implemented methods to detect crack-like features in pipeline welds using magnetic flux leakage data and pattern recognition. A screening process, for example, does not affect or change how survey data is recorded in survey tools; only how it is analyzed after the survey data is completed. Embodiments of the present invention can be used to screen for very narrow axial anomalies in the pipeline welds, and may also be used to predict the length of such anomalies. Embodiments of the present invention also produce a listing of the anomalies based on their relative signal characteristics.

Abstract: A system and method for determining electric motor efficiency includes a monitoring system having a processor programmed to determine efficiency of an electric motor under load while the electric motor is online. The determination of motor efficiency is independent of a rotor speed measurement. Further, the efficiency is based on a determination of stator winding resistance, an input voltage, and an input current. The determination of the stator winding resistance occurs while the electric motor under load is online.

Abstract: An insertion-hole blockage-rate evaluation system is applied to a heat exchanger that includes a heat transfer tube and a tube support plate having an insertion hole formed therein for inserting the heat transfer tube therethrough. The tube support plate is displayed in a three dimensional manner in an elliptical diagram with a ratio between a long axis and a short axis being in a range from 1.0 to 2.0 inclusive, each of the tube support plates is serially arranged so as not to overlap on each other, and the insertion-hole blockage-rate evaluation system includes an imaging process of color-coding and displaying the diagram displayed in the three-dimensional elliptical shape according to a value of a blockage rate of the insertion hole acquired by checking the blockage rate of the insertion hole.

Abstract: A method and a device for establishing excitation parameters, in particular for establishing an excitation profile, for MR imaging, are proposed. Elements of a k-space covariance matrix are determined for signal noise in k-space data which is captured using a plurality of receive channels in the context of data captured at an examination object. Elements of at least one image space covariance matrix are mathematically determined for a plurality of voxels of the examination object as a function of the k-space covariance matrix. The excitation parameters are established as a function of the determined elements of the at least one image space covariance matrix.

Abstract: A system and method for determining the health of a DC motor, such as a DC motor on a vehicle. The method includes measuring a current output signal of the DC motor, determining a mean of the measured current signal over a predetermined time period and determining a variance estimation of the mean of the measured current. The method then uses the variance estimation to determine the health of the motor, including an end-of-life prediction of the motor, and uses the mean of the measured current to determine the performance (torque) of the motor.

Abstract: Non-destructive material examination of a test part by scanning induction thermography improves upon the quality of a manual measurement by an inspecting person. Recorded infrared images undergo evaluation and references corresponding to the evaluation are projected onto the test piece for an inspecting person.

Abstract: The apparatus employs the remote field eddy-current (RFEC) inspection technique to electromagnetically measure physical parameters of a metallic pipe. RFEC devices inserted into and displaced along a cylindrical pipes may be used to measure the ratio of pipe thickness to electromagnetic skin-depth and thus allow for the non-invasive detection of flaws or metal loss. Typically these RFEC thickness measurements exhibit a so-called double-indication of flaws, an undesired artifact due to a double-peaked geometrical sensitivity function of the device. The method describes a means by which this double indication artifact may be removed by an appropriate processing of RFEC measurements performed by an apparatus specifically designed for this purpose. The invention is particularly well designed for applications in the oilfield industry.

Abstract: The disclosure describes methods, devices and tools useful in the non-destructive inspection and the characterization of mechanical damage such as dents in pipelines. Methods, devices and tools described herein make use of a strain severity indication combined with a material loss indication such as magnetic flux leakage to determine whether a dent comprises at least one of a crack, a gouge and corrosion. The characterization of the mechanical damage in dents of pipes may be used to determine whether and when any corrective or preventive action should be carried out.

Abstract: An inspection system for inspecting a target object is disclosed. The inspection system includes an inspection module. The inspection module includes a housing, a sensor adapted to provide sensor data relating to the target object, an inspection module processor adapted to receive the sensor data from the sensor and to provide corresponding packaged data, and an inspection module interface adapted to output the packaged data from the inspection module processor. The inspection system also includes a handset adapted to selectively mechanically engage with the inspection module. The handset includes a handset processor, a handset interface adapted to receive the packaged data from the inspection module interface and to provide the packaged data to the handset processor, and a user output interface responsive to the handset processor to output information about the target object to a user based on the packaged data.

Abstract: The present invention discloses an autonomous magnetic tomography method (MTM) and device for magnetographic identification and magnetographic analysis of mechanical flaws and defects along structures located deep in the sea or otherwise located underwater and further underground. The invention optimizes the inspection and maintenance processes of extended metallic constructions, e.g., pipelines. The device is based on the inverse magnetostrictive effect (i.e., the Villari effect)—the variation of a material's magnetic susceptibility under applied mechanical stress. The changes in magnetic susceptibility result in distribution of a magnetic field gradient along a structure's surface area, thus providing information about the presence and the value of the magnetic field anomaly at a given and precise location on the structure. The device and method is capable of autonomous and offline operation underwater at depths up to 1,500 meters below sea level.

Abstract: An apparatus for evaluating layers, including interlayer gaps, in a multi-layer structure; the multi-layer structure presenting a plurality of edges generally aligned athwart an axis; the apparatus includes: (a) a sensing unit configured for sensing at least one parameter; (b) a positioning unit coupled with the sensing unit; the positioning unit being configured to effect moving the sensing unit generally along the axis; and (c) a control unit coupled with at least one of the positioning unit and the sensing unit. The control unit provides an electrical signal to the sensing unit. The control unit monitors changes in the at least one parameter as the sensing unit moves past the plurality of edges. The control unit employs the changes in the at least one parameter to effect the evaluating.

Abstract: A method for determining tube support plate blockage of a steam generator includes the following steps: measuring at least five different eddy current values per tube support intersection; calculating a nominal clean fit radius of flow hole; determining a center signal response; converting the center signal response to a deposit thickness; determine an edge reduction; converting the edge reduction to an edge thickness; calculating the resulting flow hole radius; verifying the reasonableness of the resulting flow hole radius; and determining a virtual calibration range.

Abstract: A non-destructive inspection system that has particular application for inspecting a bore in a valve for defects. The system includes an inspection yoke having a ferromagnetic core, where a first coil is wound around the core in one direction and a second coil is wound around the core in an orthogonal direction so that orthogonal electromagnetic fields can be generated within the bore. A controller provides a current flow through the coils to generate the electromagnetic fields to detect defects in the bore.

Abstract: An apparatus and a method for detecting at least one periodically occurring defect on an object, in particular on a metal strip, in which at least one time signal is recorded from the moving object using a measuring method, the time signal is converted into a quality function using a stochastic method and one or more periodic signals in the time signal are inferred on the basis of this quality function in order to thereby detect at least one periodically occurring defect on the object. In order to obtain advantageous method properties, it is proposed to convert the time signal recorded by means of the measuring method, in particular the electromagnetic measuring method, into the quality function using a model-based estimation method, in particular using a maximum likelihood method.

Abstract: An impact detection and remediation system includes a sensing device for detecting damage events related to a structure of interest. Such damage events may include impact from a ballistic object, a tamper event, a physical impact, or other events that may affect structural integrity or cause failure. Illustratively, the sensing device is in communication with a measurement system to determine impact criteria, and a processing system which is configured to use the impact criteria to determine a direction of the initiation point of a ballistic causing the damage event.

Abstract: Method of determining an edge of a first anomaly in a wall of a pipeline from a first set of data elements representing measurements of the wall of the pipeline. An element of the first set comprises a first coordinate, a second coordinate, and a parameter being indicative for the presence and/or severity of the first anomaly a position along the wall indicated by the first and second coordinate. The method comprises determining a data element that is associated with a maximum in the severity of the first anomaly; evaluating a value of the parameter by comparing with a predetermined threshold; determining an initial edge data element for which the parameter has reached the threshold; determining a next edge data element; determining further edge data elements; and determining the edge of the first anomaly by combining the first and second coordinates of the determined edge data elements.

Abstract: An apparatus comprises an inspection vehicle, a sensor system, a positioning system, a controller, and a support system. The inspection vehicle is configured to move on a surface of an object. The sensor system is associated with the inspection vehicle and is configured to generate information about the object when the inspection vehicle is on the surface of the object. The positioning system is configured to determine a location of the inspection vehicle on the object. The controller is configured to control movement of the inspection vehicle using the positioning system and control operation of the sensor system. The support system is connected to the inspection vehicle and is configured to support the inspection vehicle in response to an undesired release of the inspection vehicle from the surface of the object.

Abstract: A technique facilitates evaluation of pipe. A sensor is positioned to examine a pipe and to obtain data on the pipe. The data obtained is analyzed on a processor-based system and compared to predetermined defect data. If the data obtained by the sensor sufficiently matches predetermined defect data, a defect is determined to enable performance of an appropriate action with respect to the pipe.

Abstract: A method implemented using a processor based device includes obtaining a measured electrical signal from an electrical device coupled to a mechanical device and generating a signal signature representative of a fault in the mechanical device based on the measured electrical signal. The method also includes determining a diagnostic parameter based on a harmonic frequency of the signal signature and determining the fault in the mechanical device based on the diagnostic parameter.

Abstract: A method for determining tube support plate blockage of a steam generator includes the following steps: measuring at least five different eddy current values per tube support intersection; calculating a nominal clean fit radius of flow hole; determining a center signal response; converting the center signal response to a deposit thickness; determine an edge reduction; converting the edge reduction to an edge thickness; calculating the resulting flow hole radius; verifying the reasonableness of the resulting flow hole radius; and determining a virtual calibration range.

Abstract: A technique that is usable with a well includes providing a model so predict measurements that are received by receivers due to transmissions by sources based on estimated positions of the receivers relative to the sources. The estimated positions each have at least two dimensions. At least some of the receivers and the sources are located in the well. On a computer, the estimated positions are automatically refined based on a comparison of the predicted measurements and actual measurements that are obtained by the receivers.

Abstract: A fan speed testing system includes a voltage regulating module, a rotational frequency collecting module, and a rotational frequency converting module. The voltage regulating module receives an AC voltage signal and converts the AC voltage signal to a variable first DC voltage signal to adjust a rotational speed of a fan. The rotational frequency collecting module detects the rotational speed of the fan and outputs rotational frequency signals. The rotational frequency converting module receives the rotational frequency signals and determines the rotational speed of the fan according to numbers and period of time level voltage switching in the rotational frequency signals.

Abstract: A system and method of signal detection from a given point, in which a radiative aperture, such as a sonar sensor, radar antenna, acoustic sensor, or the like, receives radiation from the point at more than one range. At each range, the signal incident on each point within the aperture is weighted by the cosine of the angle between a surface normal at the point on the aperture, and a vector from the point on the aperture to the given point. The physical size and shape of the aperture may also be changed to cause the aperture to subtend the same solid angle having the given point as the vertex, at each range. In this manner, the signal from the given point becomes aperture shape independent, facilitating object recognition and imaging.

Abstract: A method for determining tube support plate blockage of a steam generator includes the following steps: measuring at least five different eddy current values per tube support intersection; calculating a nominal clean fit radius of flow hole; determining a center signal response; converting the center signal response to a deposit thickness; determine an edge reduction; converting the edge reduction to an edge thickness; calculating the resulting flow hole radius; verifying the reasonableness of the resulting flow hole radius; and determining a virtual calibration range.

Abstract: Faults and fault types in electric machines can be identified based on spectra associated with stator and field currents. Signals associated with such currents can be compensated for line variations, and spectral contributions for non-eccentric machines can be reduced or eliminated to permit distinguish static eccentricities from non-eccentric machine operation. One or more of a static eccentricity, a dynamic eccentricity, and a mixed eccentricity can be identified based on spectral component magnitudes at selected frequencies.

Abstract: A method for qualifying an automated process for inspecting and sorting particles through the production and use of seed particles is disclosed. In one embodiment, seed particles are produced by forming a conformal surface layer on a plurality of particles, thereby imparting them with at least one property whose value or range of values is the same as or about the same as a value or range of values of a corresponding property of undesirable particles. By introducing a predetermined quantity of seed particles, their detection and removal by the automated sorting system can be used to periodically calibrate and qualify the sorting system without interrupting the manufacturing operations or introducing actual undesirable particles into the process stream. The production and use of seed particles to qualify an automated sorting system is particularly well-suited for use with Ti sponge sorting operations.

Abstract: Gain switching is performed by a DC amplifying circuit. The DC amplifying circuit is provided with individual gain generating circuits and a gain selecting circuit, and saturation preventing circuits are provided in earlier stages than the individual gain generating circuits. The individual gain generating circuit generates a gain G1, the individual gain generating circuit generates a gain G2 (where G2>G1), and the individual gain generating circuit generates a gain G3 (where G3>G2). The gain selecting circuit selects, as a used gain generating circuit, one of the individual gain generating circuits, and sends the output thereof to an A/D converting circuit in a later stage.

Abstract: One embodiment provides a system that analyzes a target electromagnetic signal radiating from a monitored system. During operation, the system monitors the target electromagnetic signal using a near-isotropic antenna that includes a set of receiving surfaces arranged in a regular polyhedron. Next, the system obtains a set of received target electromagnetic signals from the receiving surfaces. Finally, the system assesses the integrity of the monitored system by separately analyzing each of the received target electromagnetic signals.

Abstract: An abnormality diagnosis apparatus for an electric pump prevents an erroneous decision that a normally functioning electric pump has an abnormality. When a motor is driven by a current of the driving motor using an upper limit current I? before a predetermined time T1 passes, it is decided that there is a probability that an abnormality occurs in the pump and the decision is reported to an external device when the number of rotations of the motor is less than the lower limit number of rotations set under lower limit temperature of a hydraulic oil. When the motor is driven by limiting the current of the motor by I? and I? (<I?) after T1 passes, it is decided that there is a probability of occurrence of an abnormality when rotation of the motor stops and the decision is reported to the external device.