A wireless power transmission system has a wireless power receiving device with a wireless power receiving coil that is located on a charging surface of a wireless power transmitting device with a wireless power transmitting coil array. Control circuitry in the wireless power transmitting device may use inverter circuitry to supply alternating-current signals to coils in the coil array, thereby transmitting wireless power signals. The control circuitry may also be used to detect foreign objects on the coil array such as metallic objects without wireless power receiving coils. For example, control circuitry may use inductance measurements from the coils in the coil array to determine a probability value indicative of whether a foreign object is present on the charging surface. The control circuitry may compare the probability value to a threshold and take suitable action in response to the comparison.

The invention relates to an oscillating sensor for a measurement device comprising: an oscillator comprising: a resonance circuit for providing an oscillation signal; a gain stage configured to provide a feed-back to the resonance circuit to inject energy for excitation of the oscillator to maintain oscillation; at least one calibration element to adjust the open loop gain of the oscillator; a calibration unit to provide a modulated calibration control signal to selectively adjust an electrical measure of the at least one calibration element based on at least one predetermined duty cycle, wherein the calibration unit is further configured to provide the modulated calibration control signal with at least one cycle frequency which depends on the oscillation frequency.

Example embodiments relate to a method of measurement, an apparatus for measurement, and an ingot growing system that measure properties relating an induction heating characteristic of a graphite article. The method of measurement comprises an arranging step of arranging a graphite article to the coil comprising a winded conducting wire; and a measuring step of applying power for measurement to the coil through means of measurement connected electronically to the coil, and measuring electromagnetic properties induced in the coil. The method of measurement and the like measure electromagnetic properties of graphite articles like an ingot growing container, and an insulating material, and provide data required for selecting so that further enhanced reproducibility for growth of an ingot can be secured.

Example embodiments relate to a method of measurement, an apparatus for measurement, and an ingot growing system that measure properties relating an induction heating characteristic of a graphite article. The method of measurement comprises an arranging step of arranging a graphite article to the coil comprising a winded conducting wire; and a measuring step of applying power for measurement to the coil through means of measurement connected electronically to the coil, and measuring electromagnetic properties induced in the coil. The method of measurement and the like measure electromagnetic properties of graphite articles like an ingot growing container, and an insulating material, and provide data required for selecting so that further enhanced reproducibility for growth of an ingot can be secured.

Method for calculating model parameters for a coil (L), comprising of: incorporating the coil into a converter (1) with a switching element (2); connecting a resistive load (9); applying an input voltage (U.sub.in); controlling the switching element in order to obtain a periodically varying voltage across the coil; measuring at least a first and second quantity representative of respectively the voltage (U.sub.L) across and the current (i.sub.L) through the coil; determining at least one voltage value and at least one current value on the basis of the measured first and second quantity; calculating a loss resistance and/or a loss power of the coil on the basis of the at least one voltage value and the at least one current value.

A solid state drive (SSD) with improved techniques for testing power loss protection (PLP) capacitors and a method for testing PLP capacitors of SSDs is disclosed. In one embodiment, the SSD includes a memory controller and one or more non-volatile memory devices and a volatile memory device coupled to the memory controller. The SSD also includes a PLP capacitor configured to supply a first voltage to the memory controller, the one or more non-volatile memory devices, and the volatile memory device in the event of a power loss or failure of the SSD. In one embodiment, the PLP capacitor is further configured to increase the first voltage to a second voltage prior to testing the PLP capacitor. In another embodiment, the memory controller is configured to reduce a volume of data stored in the volatile memory device prior to testing the PLP capacitor.

An RF cable includes a connector housing having an RF signal output interface, a cable body having a first end portion connected to the connector housing and a second end portion comprising an RF signal input interface, an RF signal transmission path formed from the RF signal input interface through the cable body and the connector housing to the RF signal output interface, and a power measurement device integrated into the connector housing and configured to measure a power value of an RF signal transmitted through the RF signal transmission path. The RF cable further includes a measurement signal output interface, and a measurement signal transmission line connecting the power measurement device to the measurement signal output interface, the power measurement device being configured to output a measurement signal indicating the measured power value of the RF signal at the measurement signal output interface.

In a wireless charging system, a power-transmitting node (TX) has a power transmitter for transmitting power wirelessly to a power-receiving node (RX), a sampling and sensing circuit, a processor, and a signal receiver for receiving signals from the RX. The processor detects the presence of a foreign object (FO) during a power-transfer session using Quality Factor (QF) values. Estimated QF parameters are determined via exponential curve fitting using peak values of a damped sinusoidal waveform generated by a resonant circuit. Then the estimated parameters in the exponential curve are used to calculate the QF, which provides a robust measurement result even in a noisy environment.

A method of measuring a Q-factor in a wireless power transmitter includes charging a capacitor in a LC tank circuit that includes a transmission coil to a voltage; starting a Q-factor determining by coupling the LC tank circuit to ground to form a free-oscillating circuit; monitoring the voltage across the capacitor as a function of time as the LC tank circuit oscillates; and determining the resonant frequency and the Q-factor from monitoring the voltage.

A wireless power transmission system has a wireless power receiving device that is located on a charging surface of a wireless power transmitting device. The wireless power receiving device has a wireless power receiving coil and the wireless power transmitting device has a wireless power transmitting coil array. Signal measurement circuitry coupled to the coil array may make measurements while the control circuitry uses the inverter circuitry to apply excitation signals to each of the coils. Foreign objects on the coil array such as metallic objects without wireless power receiving coils can be detected using foreign object detection. When multiple wireless power receiving devices are present on the wireless power transmitting device, steps may be taken to isolate measurements from the coils associated with each wireless power receiving device. Foreign object detection may then be performed on these modified measurements.