An abnormality detection apparatus and an abnormality detection method are provided. In a motor abnormality detection apparatus for detecting an abnormality of a motor, a current measurer measures the current flowing through the motor. A voltage measurer measures the voltage applied to the motor. A motor state detector detects the operation state of the motor. A current estimator estimates the current flowing through the motor based on the measured value of the voltage measurer and the detection result of the motor state detector. An abnormality detector detects an abnormality of the motor based on the measured value of the current measurer and the estimated value of the current estimator. The motor abnormality state detection method includes the steps of measuring the current flowing in the motor and the voltage applied to the motor; detecting the operation state of the motor, estimating the current flowing through the motor based on the measured voltage and the detected operation state, and detecting an abnormality of the motor based on the measured current and the estimated current. The abnormality detection apparatus and an abnormality detection method which can detect whether the current measurer itself operates abnormally to accurately detect an abnormality of the motor, and detect the abnormality of the motor due to the abnormality of the current measurer and the poor connection between the motor and the power source.
The technique of the present invention sets a torque voltage to be applied to a motor in response to a required torque and adjusts the duty of an inverter to ensure application of the torque voltage according to the observed voltage of a battery. In a motor controller constructed to attain such control, before a start-up of normal operation of the motor, a fixed duty is set for switching the inverter to apply a voltage to the motor. The value of electric current running in response to the applied voltage is measured. The mapping of the value of electric current to the source voltage in the case of switching the inverter at a fixed duty is stored in advance in the form of a table. The procedure reads the true value of the source voltage from the table and thereby specifies an offset error occurring in a voltage sensor of the battery. The procedure then corrects the observed voltage of the battery and adequately regulates the torque voltage.
A test method characterizes current behavior of power components (e.g., semiconductor packages) within an electronic system. One or more electrically conductive loops are formed with a first printed circuit board of the electronic system; these loops surround, at least in part, one or more electrical vias of the first printed circuit board. One or more power components connect to the vias to obtain power therethrough. Current characteristics are measured from one or more vias to assess transient and steady-state currents of components within the system. Power dissipation may be determined from the current. The loops may be formed within tracks of internal layers of the first printed circuit board, or a second printed circuit board may form the tracks.
A driving apparatus includes a plurality of driving devices, a plurality of detectors for detecting a malfunction of the driving devices, and a controller, which is responsive to a detection result of the detectors, for decreasing a driving speed of a driving device at which a malfunction is detected and increases a driving speed of another driving device.
A driving apparatus includes a plurality of driving devices; a plurality of malfunction detectors for detecting a malfunction of the driving devices; a plurality of electric current setting devices for setting electric currents through the driving device; and a controller for controlling the plurality of driving devices, malfunction detectors and the electric current setting devices. The controller is effective to set standard electric currents, maximum tolerable electric currents, standard speeds, minimum rotatable speeds and maximum tolerable speeds of the plurality of driving devices, and a total current applied to the plurality of driving devices, wherein the driving devices are given priorities depending on influential ranges of functions of the driving devices.
In a method for error detection of a brushless electric motor, at least one first motor parameter is measured or determined, and a second, estimated motor parameter is estimated on the basis of the first motor parameter. The second, estimated motor parameter is compared to a second, measured or determined motor parameter. An error of the electric motor can be found out according to the comparison.
