The present disclosure describes an apparatus, system, and method of use for detecting electrical faults in a multiphase electric machine. Often in platforms which require redundant reliability or have no readily available electrical connection to earth use ungrounded electrical architectures. This allows the system to continue normal operation even if there is an unintended short circuit or current path (electrical fault) between a phase of an electric machine and its case or some other part of the platform. It is important to be able to readily identify any fault in the phase windings of machinery operating in an ungrounded electrical architecture. Since a single fault in an ungrounded system will not cause any additional current draw or otherwise affect the system, it can be difficult to detect that a fault has even occurred. This provides an advanced warning system.

A motor control apparatus according to one aspect of the present invention is configured to be connected to a motor by a wiring line, and includes: a motor driving unit for driving a motor; a current command unit for commanding supply of current to the motor driving unit; and, a miswiring detecting unit for detecting miswiring of lines connected to motors by acquiring via wiring lines a signal indicating the motor temperature detected by a motor temperature detector provided for the motor, wherein the miswiring detecting unit detects presence or absence of miswiring of the wiring lines, based on the change of the motor temperature when the current command unit commands supply of reactive current to the motor driving unit.

During a transient operating condition in an electric machine, a diagnostic routine associated with the electric machine may erroneously indicate a fault. According to the disclosure, a flag is set when a transient condition is detected. The flag is communicated to the diagnostic routine. The output of the diagnostic routine may be altered when the flag is set, i.e., when a transient is detected.

The invention relates to a circuit assembly (10) for fault detection in an ungrounded high-voltage system (20) having a connected inverter (4) and having at least one resistor (5) between a high-voltage potential (7a, 7b) of the high-voltage system (20) and a reference potential (8), the circuit assembly (10) comprising: a sensing circuit (1), which is designed to tap a voltage from the resistor (5), to generate a first measurement value therefrom and to provide the first measurement value at an output (1c, 1d); and an evaluation device (2), which is connected to the output (1c, 1d) of the sensing circuit (1), the evaluation device (2) being designed to compare the first measurement value with a first limit value and to output a first signal if the first measurement value exceeds the first limit value.

A method of controlling a motor of a power steering system is provided. The method generates a direct-axis voltage command and a quadrature-axis voltage command based on a current measurement signal received from the motor. The method transforms the direct-axis voltage command and the quadrature-axis voltage command into an alpha voltage command and a beta voltage command. The method determines an offset error in the phase current measurement based on the alpha and beta voltage commands.

The controller is equipped with a detection signal acquiring unit adapted to acquire a detection signal from a sensor that detects a physical quantity caused by vibrations generated at a detected location due to rotation of an electric motor, a phase information acquiring unit adapted to acquire phase information of the electric motor, a time width determining unit adapted to determine a time width, which coincides with a period of a phenomena occurring at the detected location due to rotation of the electric motor, on the basis of the phase information, a signal dividing unit adapted to divide the detection signal based on the determined time width, and an adding and averaging unit adapted to add and average a plurality of divided signals divided by the time width.

An engine generator includes a generator body connected to an engine, a converter including rectifiers that convert an output from the generator body to DC current, an inverter that converts an output from the converter to AC current, an input voltage detector that detects an input voltage from the generator body to the converter, and an AC current detector that detects an AC current output from the inverter. An abnormality in the engine generator is determined if a state that a current detected by the AC current detector is not higher than a first threshold value and a duty ratio of a voltage detected by the input voltage detector is not higher than the second threshold value continues for a first predetermined time; or if the current detected by the AC current detector is not higher than a third threshold value and the duty ratio change rate is not higher than a fourth threshold value.

Systems and apparatuses include an alternator including a stator and a rotor structured to be coupled to a crankshaft of a prime mover, and processing circuits structured to: determine a crankshaft position, associate a crankshaft timestamp with the crankshaft position, determine a stator voltage waveform position, associate a stator voltage waveform timestamp with the stator voltage waveform position, determine a common time base using the crankshaft timestamp and the stator voltage waveform timestamp, determine a rotor position based on the crankshaft position and associated with the common time base, determine a load angle based on the rotor position and the stator voltage waveform position using the common time base, compare the load angle to a stability limit, and transmit a predicted pole slip signal to at least one of the prime mover or the alternator to inhibit a pole slip event when the load angle exceeds the stability limit.

An insulation inspection device for motors includes an inverter for driving a motor, a partial discharge detecting unit for determining soundness of the motor, and a control circuit for controlling the inverter. The control circuit adjusts a switching interval of a voltage pulse of the inverter so as to be equal to a pulse round-trip propagation time between the inverter and the motor, thereby generating surge voltage higher than driving voltage for the motor, between the motor and ground, and adjusts a switching time for each phase of the inverter, thereby generating surge voltage higher than driving voltage for the motor, between phases, thus performing insulation inspection.

A detecting apparatus for AC motor malfunction by using a current delay property of an AC motor and outputting a malfunction signal to an alarming device is presented. The detecting apparatus for AC motor malfunction includes a voltage phase delay setting unit, a voltage phase conversion unit, a current phase detecting unit, a current phase conversion unit, a phase comparator, a sawtooth wave generating unit, a phase difference detecting unit, a phase shift bandwidth setting unit, a noise filtering unit, and a malfunction signal output unit.