4results about How to "Exact impedance" patented technology

The invention discloses a linearization method and system for a nonlinear high-frequency model of steel under lightning stroke, and relates to the technical field of electromagnetic engineering, and the method comprises the steps: constructing an impedance model of the steel through employing a PEEC method; the parameters of the steel are extracted through pulse current; and linearizing the nonlinear characteristics of the steel through an impedance model. According to the method, the impedance of the steel can be accurately modeled by adopting a partial capacitance equivalent circuit method and combining the characteristics of the magnetic material and the high-frequency eddy current effect, and the modeling precision is remarkably improved. A traditional electrical steel parameter extraction method cannot simulate actual lightning stroke current conditions, so that the authenticity and accuracy of experimental data are insufficient. According to the impulse current injection method provided by the invention, the impedance parameter of the steel can be directly extracted by measuring the transient response of the steel under the actual lightning stroke current and combining with the fast Fourier transform technology to process data, so that the authenticity and accuracy of experimental data are ensured.

An induction heating device according to an embodiment comprises: a working coil which is disposed at a position corresponding to a heating area where an object to be heated is placed, and forms a load together with the object to be heated; a resonant capacitor which forms a resonant circuit together with the working coil; an inverter circuit which includes a plurality of switching elements and supplies a current to the working coil; a first voltage sensor which measures a voltage value applied to the resonant capacitor; a second voltage sensor which measures a supply voltage value supplied to the resonant circuit through the inverter circuit; and a controller which, when the working coil is in operation, calculates at least one of the resistance value of the load and the inductance of the load on the basis of the voltage value of the resonant capacitor and the supply voltage value.

This disclosure provides an interconnect structure impedance measurement circuit. By optimizing the Wheatstone bridge structure, it employs three parallel branches. In one branch, the interconnect structure to be measured is connected in series. In the other two branches, two resistors are connected in series. By controlling the branch containing the interconnect structure and one of the other two branches to be simultaneously turned on, the voltage between the two turned-on branches is measured. The impedance of the two interconnect structures is calculated based on the current flowing into the interconnect structure impedance measurement circuit, the measured voltage, and the resistance in the branches. This disclosure allows for convenient, large-scale, and accurate measurement of interconnect structure impedance, and enables real-time and accurate monitoring of the impedance of a single interconnect structure in reliability experiments. This disclosure also provides an interconnect structure impedance measurement device and method.

Various embodiments set forth medical devices. In some embodiments, a medical device includes an impedance bridge, an instrument head including one or more electrode pairs and a calibration impedance, and one or more wire pairs coupling the impedance bridge to the one or more electrode pairs and the calibration impedance. The disclosed medical devices compensate for extraneous factors caused by manufacturing and material variations while measuring tissue impedance.