There is provided a diagnostic apparatus including: a data acquisition unit configured to acquire target data relating to a current value between a power conversion apparatus and a motor; a detection unit configured to detect a peak value in a time series waveform of the target data; a counting operation unit configured to use a frequency counting method to calculate an amplitude of the peak value and a frequency of occurrence of the amplitude; and a diagnostic unit configured to diagnose an abnormality of the motor based on the amplitude and the frequency of occurrence. The diagnostic unit diagnoses that the motor is abnormal when a statistic which is calculated from the amplitude and the frequency of occurrence of the amplitude does not satisfy a predetermined reference.

The subject of the invention is a method and a device for determination of a torsional deflection of a rotation shaft in the electromechanical drivetrain. The method uses a current and a voltage signals measurement of the driving electrical machine and an angular speed measurement of the shaft of the drivetrain and includes the step of measuring of a voltage U.sub.DC of the DC link unit of a converter; the step of calculating a value of a load torque T.sub.load of the driving electrical machine; the step of detecting of an oscillation O.sub.SC(T.sub.load) in the load torque T.sub.load and calculation magnitudes of characteristic frequencies of Fast Fourier Transform FFT(U.sub.DC) of the voltage U.sub.DC of DC link unit; the step of determining of a timestamp indicators t.sub.Tload for oscillations O.sub.SC(T.sub.load) and t.sub.FFT of U.sub.DC for magnitudes of characteristic frequencies of FFT(U.sub.DC) of the voltage U.sub.DC of DC link unit; the step of comparing the value of the timestamp indicators t.sub.Tload and t.sub.FFT and determining a torsional deflection of the rotation shaft if t.sub.Tload<t.sub.FFT; the step of presenting the result of the comparison to the user in a diagnostic unit.

A system is provided including a current sensor arranged to sense current drawn by an electric motor of a powered device through an AC power line from a power supply and provide current data related to the powered device; a monitoring device arranged to receive the current data from the electrical sensor, the monitoring device including a controller processing the current data to obtain performance data associated with the powered device, the performance data relating to load applied to the electric motor; a data communication device communicating with the monitoring device and arranged to receive the performance data associated with the powered device; and a computing device including a graphical user interface, the computer device receiving a user's selection of the powered device from a list of powered devices and presenting the performance data to the user via the graphical user interface in response to the user's selection.

A method and device estimate life consumption for an electronic component for use with an electric motor. The method and device allow maximal/minimal temperature values of semiconductor devices to be continuously monitored to allow on-cycle thermal damage and post-cycle damage to be determined in a parallel manner.

An electric power conversion device has a function of detecting, at low cost and at an early stage, a sign of insulation failure of a transformer or a rotational machine. This electric power conversion device is provided with an inverter circuit and a PWM signal generation unit that makes a comparison between a carrier signal and a voltage command value and generates a PWM signal for driving the inverter circuit. The electric power conversion device feeds and receives electric power through connection to a transformer or a rotational machine provided with a winding wire. The electric power conversion device is provided with: a current sensor that detects a current to be fed to or received from the transformer or the rotational machine; and a diagnostic unit that diagnoses insulation degradation of the transformer or the rotational machine.

To enable early detection of AC insulation faults, or to permit easier, faster and more accurate measurement of small currents in inverters, a current measuring circuit for a converter is provided. The current measuring circuit has a positive supply rail, a negative supply rail, a reference potential rail and a current measuring device that contains a Y-capacitor and a current sensor connected in series therewith. The load current can be decoupled from the measurement current through the at least one Y-capacitor, so that at high load currents even small fault currents can be acquired reliably with the current sensor.

Disclosed is a traction battery self-heating control method and a device. Acquiring a second temperature of a rotor at a current sampling time according to system parameters and a first temperature of the rotor at a previous sampling time, and estimating a third temperature of the rotor at a next sampling time according to the first temperature and the second temperature, and stopping the self-heating of the traction battery when the third temperature reaches a demagnetization temperature of the rotor. Whether to stop the self-heating of the traction battery is determined by estimating a rotor temperature under the self-heating condition, and comparing the rotor temperature with the demagnetization temperature of the rotor, and thus the self-heating control of the traction battery is realized.

Systems and methods are disclosed for voltage-less electrical signature analysis for fault protection. The systems and methods described herein may involve determining voltage values for a motor (which may then be used to estimate a speed of the motor) when complete voltage measurements may not be available, or may only be temporarily available. More specifically, the systems and methods described herein may address three scenarios, which may include at least: (1) when only a single phase voltage input is available for a three-phase motor, (2) when no voltage input is available, or (3) when a voltage input is only available for a limited period of time (for example, during a learning phase of the motor).

Various aspects of the disclosure relate to evaluating the electromagnetic impedance characteristics of a material under test (MUT) over a range of frequencies. In particular aspects, a system includes: an electrically non-conducting container sized to hold the MUT, the electrically non-conducting container having a first opening at a first end thereof and a second opening at a second, opposite end thereof; a transmitting electrode assembly at the first end of the electrically non-conducting container, the transmitting electrode assembly having a transmitting electrode with a transmitting surface; and a receiving electrode assembly at the second end of the electrically non-conducting container, the receiving electrode assembly having a receiving electrode with a receiving surface, wherein the receiving electrode is approximately parallel with the transmitting electrode, and wherein the transmitting surface of the transmitting electrode is larger than the receiving surface of the receiving electrode.

An electrical power generating assembly (20) for a wind turbine (1). The electrical power generating assembly comprises a gearbox (22) comprising a gearbox output shaft, a generator (24) comprising a rotor (32) that is coupled to the gearbox output shaft; and a current measuring module (40) located between the gearbox (22) and the generator (24). The current measuring module (40) comprises: an electrical pickup (42) mounted to the electrical power generating assembly (20), wherein the electrical pickup (42) includes an electrical contact (44) that engages with a slip ring (48) associated with the rotor (32). The current measuring module further comprises: a first current measuring device (50) mounted with respect to the electrical pickup (42) to detect current flowing at least through the electrical pickup; and a second current measuring device (52) mounted with respect to the electrical pickup (42) to detect current flowing through at least a component associated with the gearbox output shaft.