Disclosed is a method and apparatus for real-time estimation of full parameters of a permanent magnet synchronous motor. According to this method and apparatus, it is possible to estimate in real time all four parameters of a permanent magnet synchronous motor without additional signal injection.

In addition to the state equation, the “stator current ripple model” is additionally used to fundamentally solve the rank deficiency problem in the state equation without injecting additional signals. All four parameters of a permanent magnet synchronous motor can be estimated in real time.

The invention relates to a device for controlling armature solenoid provided with a DC voltage source (14), at least one buffer capacitor (18), which is connected in parallel to the DC voltage source (14) and has a known capacitance (C), and a first switch (28), which is arranged between the DC voltage source (14) and the buffer capacitor (18). The exciter coil (16) and a second switch (30) arranged in series therewith are connected in parallel to the buffer capacitor (18). A control and evaluation unit (22), when the buffer capacitor (18) is charged, opens the first switch (28) and closes the second switch (30) in order to determine, on the basis of the measurement voltage (20), the frequency of the resonant circuit having the capacitance (C) of the buffer capacitor (18) and the inductance (L) of the armature solenoid (12). The inductance (L) of the armature solenoid (12) is determined on the basis of the frequency, and the air gap width (h) of the armature solenoid (12) is determined on the basis of the inductance. The PWM control signal with which the armature solenoid (12) is operable in order to generate a predefined force to be applied by the armature solenoid (12) is applied to the second switch (30) on the basis of a look-up table or a mathematical modelling of the electromagnetic behavior of the armature solenoid (12).

A method for measuring a coil property, modeled as a parallel-circuit including a capacitance with a series-circuit including a DC-voltage and frequency-dependent resistance, and an inductance and current-voltage converter series connected, by: applying an AC-voltage, having a first-frequency and a DC-voltage component, to the coil and a voltage at the current-voltage converter is captured at a second-frequency, and the impedance and phase-angle at the first-frequency are derived from n-measured values; and applying an AC-voltage, having a third-frequency differing from the first and having a DC-voltage component, to the coil and voltage at the current-voltage converter is captured at the second or fourth-frequencies, in which the impedance and phase-angle at the third-frequency are derived from m-measured values for the DC-voltage resistance.

A method for determining an impedance of an electrically conducting device, such as a battery or a welded metal joint, includes applying a time-varying electric current to the electrically conducting device. The current varies at least between a first level and a second level. The current changes between the first level and second level within a time interval that is so short that a voltage response of the electrically conducting device exhibits a first local voltage extremum followed by a decay. An ohmic resistance voltage is adopted by the voltage response, when the first local voltage extremum has decayed. The method further includes acquiring the voltage response at least partially and determining an impedance of the electrically conducting device from the acquired voltage response.

A system may include a resistive-inductive-capacitive sensor, a driver configured to drive the resistive-inductive-capacitive sensor at a driving frequency, a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to measure phase information and amplitude associated with the resistive-inductive-capacitive sensor, and a noise detection circuit communicatively coupled to the measurement circuit and configured to determine a presence of external interference in the system based on at least one of the phase information and the amplitude information.

A method is disclosed. The method includes measuring at least one electrical parameter (R, L, C) of at least one wire (10) in a motor vehicle (100) at a certain time instance (t.sub.i) to obtain measurement data (M(t.sub.i)); comparing the measurement data (M(t.sub.i)) with comparative data (C(t.sub.i)) held in a data storage (5); and taking a predefined action (63) dependent on the comparing.

A sensor including a circuit carrier, a number of measuring inductors on the circuit carrier, and a reference inductor that is coupled to the measuring inductors.

Foreign object detection for wireless power transmitters and related apparatuses and methods are disclosed. An apparatus includes an analog-to-digital converter to sample at least one of a coil voltage potential and a coil current representation of a transmit coil inductively coupled to a receive coil of a wireless power receiver with a distance between the transmit coil and the receive coil. The apparatus also includes a processing core to determine an expected reference Q-factor value responsive to the at least one of the sampled coil voltage potential and the sampled coil current representation. The expected reference Q-factor value indicates a Q-factor value expected at a predetermined reference wireless power transmitter inductively coupled to the wireless power receiver with a reference distance from a reference transmit coil of the predetermined reference wireless power transmitter to the receive coil of the wireless power receiver.

A first-order resistor-inductor (RL) circuit is allowed to alternate a direct-current excitation response and a zero-input response so that a direct-current magnetic field generated by an inductor magnetizing coil changes alternately in magnetic field intensity with a change in magnitude of current. After a testing object is placed in the direct-current magnetic field changing alternately in magnetic field intensity, the testing object is magnetized and also causes a change in inductance of the magnetic field. Whether a change occurs in electromagnetic properties of the testing object can be determined and detected by detecting the inductance change of the magnetizing coil or detecting electrical characteristic change caused by the inductance change of the magnetizing coil, thereby determining whether quality defects such as steel wire cracks and wire breakage in a steel wire rope occur. Alternatively, the properties such as a sectional area or a zinc layer thickness can be analyzed.

A semiconductor device includes an internal circuit connected to at least one pad. A first inductor element is connected between the at least one pad and the internal circuit, a second inductor element coupled to the first inductor element and generating an induced voltage due to an overcurrent flowing in the first inductor element. An event detection circuit includes a monitoring element connected to the second inductor element. The monitoring element is configured to generate an event detection signal by sensing changes in properties of the monitoring element caused by at least one of the induced voltages generated in the second inductor element and a current flowing in the second inductor element. The internal circuit supplies an operating voltage to the event detection circuit, and determines whether an event causing the overcurrent has occurred by receiving the event detection signal from the event detection circuit.