132 results about "Electrical model" patented technology

A method and system for measuring the electrical impedance of sections of a living body. The measurement is carried out utilizing a plurality of electrodes each of which is disposed on a section of the living body, where the electrodes are capable of applying an electrical current through at least one probed section, and measure the electrical voltage over the probed section. The voltages over the probed sections are measured and the impedances (Z(t)) and their changes (ΔZ(t)), and the resistances R(t) and their changes (ΔR(t)), are calculated, by considering the electrical current distortion components resulting from the electrical currents flowing in the other sections which are not probed, utilizing an electrical model based on the distribution of the electrical currents through the body sections. The measuring is preferably performed by applying an electrical current through the probed section of the living body via a pair of electrodes, and measuring the electrical voltage over the probed section and over the other sections, applying an electrical current through one or more of the other sections and at each instance measuring the electrical voltage over the other sections; and calculating the impedance and resistance and the changes utilizing the measurements and the applied currents, according to the electrical model.

The invention provides a system for simultaneous representation of single cell Young's modulus and cell membrane specific capacitance based on a microfluidic technology. The system makes a cell equivalent to an isotropic super-viscoelastic body, based on ABAQUS mechanical simulation, the relation between the displacement generated by instantaneous entrance of the cell front end into a compression channel, and the cell size, the Young's modulus, the pressure intensity, and geometric parameters of the compression channel, and the Young's modulus of the cell can be calculated. In addition, the invention also puts forward an equivalent electrical model for the cell to pass through the compression channel, the relation between the cell membrane capacitance, cytoplasm resistance, cell and compression channel wall leakage resistance, electrical parameters of the compression channel itself, and the impedance spectrum can be obtained, the impedance change caused by passing of the cell through the compression channel is converted to cell membrane specific capacitance, so that the cell membrane specific capacitance of the single cell can be calculated, thus realizing synchronous measurement of the single cell Young's modulus and cell membrane specific capacitance.

The invention relates to a method for setting a high-pressure high-power thyristor electrothermic model and a simulating method. In the invention, first a thermal impedance model of a thyristor is calculated and set according to the finite element method, and a Foster network thermal impedance model is expressed by the identical transformation, subsequently a thyristor equivalent electric model is set by using the mathematical method. The loss Pave(t) is determined by the switch-on forward voltage drop Vtm and the working current IA, an electrothermic model of the thyristor is set by connecting the relation of the variants such as the switch-on forward voltage drop Vtm, the working current IA, the loss Pave(t), the junction temperature TJ and the like, then the simulation is conducted on a Pspice software. The model of the invention contains a thermodynamics and electrics model, which can provides the dynamic relationship between the heating parameters and the electric parameters, can be used for simulating the transient and steady junction temperature change and predicting whether the thyristor works in the safe area, also used for insulating the junction temperature change under the sine semi-wave surge current surge and predicting whether the thyristor fail.

The present invention disclosures a test system and test method for a simulation experiment of gas hydrate in a porous medium. The test system comprises a reactor, a sensor system, a hardware interface apparatus and a data processing system; the reactor is used for containing tested medium, the sensor system is mounted inside the reactor, and the sensor system is connected to the data processing system through the hardware interface apparatus; the test method comprises a procedure of experiment and measurement data acquisition, and a procedure of analyzing and processing measurement signals; by establishing of electrical model I, acoustic model II and the fused model III, realizing the simulation of the synthesis/decomposition processes of gas hydrate in the deposits in laboratory environment and implementation of the acoustic and electrical parameters combined test, an accurate gas hydrate saturation calculation model can be established at last.

The invention relates to an equivalent modeling method based on wind speed distribution characteristics in a wind power plant. The equivalent modeling method comprises the following steps: acquiring the topological structure of a target wind power plant; performing grouping on wind turbines in the plant according to the terrain condition, wherein each group includes a plurality of wind turbine clusters; establishing a simplified mechanical model for each wind turbine cluster; establishing an equivalent single-generator electrical model of the whole wind field comprising a coil wound rotor asynchronous generator state space model, wherein the stator side is directly connected with an equivalent unit transformer, and the rotor side is connected with an equivalent back-to-back converter; and setting the set value of the voltage of a direct-current bus to be the same as the voltage of a single generator, wherein the pulse width modulation control strategy of the power grid side and the rotor side is replaced with an equivalent controlled voltage source, and an equivalent converter model is established. The modeling method can be used to better satisfy requirements of practical applications.

The invention discloses an automatic generation method of a distribution network single-line graph of a hybrid-type layout. The method includes: step 1, importing electrical models of a distribution network; step 2, abstracting the electrical models of the distribution network as an undirected graph of "node-edge", wherein management equipment is abstracted as nodes, primary management subordinateto all the management equipment is used an internal layout elements of the nodes, external electrical connections of the primary equipment inside all the nodes are converted into connection points ofthe nodes, and for primary equipment not contained in the management equipment, single-end equipment or equipment connected with the management equipment is used as entries, and a trunk-spur model isformed through searching for electrical topological relationships; step 3, carrying out laying-out and line routing on insides of the nodes; step 4, carrying out uniform laying-out and position regularization on the undirected graph of "node-edge"; step 5, using a line routing algorithm to carry out line routing on connection relationships among the nodes; and step 6, converting the undirected graph of "node-edge" into the distribution network single-line graph. Engineering implementation efficiency is improved.

The invention concerns a method, device and computer program product for controlling a voltage source converter (16; 20) connected to a power grid (12; 24). The device (25; 26) includes a first input for receiving at least one detected electrical property (E, i) of an interface between the grid and the voltage source converter, and a control entity (27; 28) arranged to control the voltage source converter (16; 20) through using a control signal (v_REF,TR) obtained through using a mapping of an electrical model of a non-salient synchronous machine onto an electrical model of the voltage source converter and through applying the detected electrical property of the interface between the grid and the voltage source converter in said mapped model, where the electrical model of the non-salient synchronous machine reflects the electrical dynamics of this synchronous machine.

A method is provided to evaluate substrate noise propagation in an integrated circuit design, the method comprising: providing a tile definition that specifies an electrical model associated with instances of the tile; mapping a plurality of respective tile instances to respective locations of the substrate; obtaining respective waveforms indicative of digital switching induced power grid fluctuations associated with the respective identified contacts; and associating a voltage with a selected tile instance of the tile grid that is indicative of substrate noise injection due to waveforms associated with contacts encompassed by the selected tile instance.

A device for controlling an electromechanical actuator includes an electric motor and an actuator operated by the electric motor. It also includes a digital signal processor (DSP) providing data of reference voltages (Ud_—ffw, Uq_—ffw) on the basis of an decoupled electrical model of the motors. The processor has at least one Park transformation module receiving measurement data for the currents of at least two supply phases of the motor (i_mot_2, i_mot_3) and a datum for the estimated angle of the motor (θ_estimated) and transforming them into data regarding the component of current with stator current axis (id) and the component of current in quadrature with the stator current (iq).

The invention provides a wind turbine generator control system hardware in-loop simulation and test platform. The platform comprises a computer equipped with GH Bladed software, an RTDS, a communication PLC and a control system of a wind turbine generator, wherein a wind model of the wind turbine generator, a mechanical model and a pneumatic model are established in the GH Bladed software, an electrical model of the wind turbine generator is established in the RTDS, an electric power electronic switch model is employed to support current transformer controller hardware in-loop simulation, bidirectional real-time communication between the GH Bladed software and the RTDS is realized through the communication PLC, the control system of the wind turbine generator employs a control system configuration of an actual fan blower, is realized through employing a physical controller and comprises a main control PLC and a current transformer controller, a main control algorithm of the wind turbine generator is operated through the main control PLC, and same functions as an actual set main controller are performed; a current transformer control algorithm is operated through the current transformer controller, and pulse width modulation pulses of a current transformer and a protection circuit of the current transformer are outputted. The platform is advantaged in that the platform can be used for testing commercial main controllers and current transformer controllers.

The invention relates to a method, a device and a system for battery internal temperature estimation and a vehicle utilizing the method, the device and the system, aiming to solve the problems of pooraccuracy and high cost in battery internal temperature measurement and incapability of guaranteeing system reliability, in the prior art. The method includes acquiring terminal voltage and terminal current of a battery, battery coolant outlet temperature and battery surface temperature at the current time, estimating currently open-circuit voltage, determining currently heat production rate of the battery according to the open-circuit voltage, the currently terminal voltage and current of the battery, and estimating currently internal temperature of the battery according to the heat production rate, the battery coolant outlet temperature, the battery surface temperature, the internal temperature of the battery at the first time, and a thermal electrical model of the battery.

A system and method for controlling a rotating electromagnetic machine. The rotating machine, such as a permanent magnet motor or switched reluctance motor, includes a stator having a plurality of phase windings and a rotor that rotates relative to the stator. A drive is connected to the phase windings for energizing the windings. The control system includes an estimator connectable to the machine for receiving signals representing the phase winding voltage and rotor position. The estimator outputs parameter estimations for an electrical model of the machine based on the received voltage and rotor position. A torque model receives the parameter estimations from the estimator to estimate torque for associated rotor position-phase current combinations of the machine. A controller outputs a control signal to the drive in response to a torque demand and rotor position signals and the torque model. In certain embodiments, a solver uses the torque model to generate energization current profiles according to desired machine behavior, such as smooth torque and/or minimal sensitivity to errors in rotor position measurement.

The invention discloses an equivalent circuit model for a schottky diode, which comprises a single-body part model of the schottky diode, as well as parasitic resistor and parasitic inductance parts which are serially connected with the single-body part of the schottky diode. Two port parts of the model are in parallel connected with a parasitic PN junction structure and a parasitic silicon substrate structure respectively. The model integrally comprises the influence of various parts related to a physical structure of the schottky diode on electrical characteristics of direct current and high frequency of the schottky diode, so the model can be directly used for circuit simulation of direct current and high frequency of the schottky diode, and can be conveniently used for stimulating the electrical characteristics of direct current and high frequency of the schottky diode. The invention also provides a test flow and a parameter extraction method based on the model, which can largely improve the extraction efficiency of parameters of an equivalent circuit electrical model of the schottky diode and the fitting effect of the model on electrical characteristics of devices.

A method for analyzing the structure of an electrically conductive object, the method comprising the steps of: (i) obtaining electrical impedance data for the object over a range of frequencies; (ii) analyzing the obtained electrical impedance data using a transfer function of an assumed electrical model to determine a plurality of electrical impedance properties for the object; (iii) constructively combining selected ones of the determined plurality of electrical impedance properties to provide at least one parametric impedance value for the object; and (iii) imaging one or more of the determined parametric impedance values.

The invention provides a subway traction system net voltage interruption, mutation and fluctuation testing system and method, and relates to the railway train operation maintenance technical field; a real time simulation device in the system loads a preset subway vehicle electric model and a subway vehicle kinetic model; a host monitoring device adjusts parameters of the subway vehicle electric model and the subway vehicle kinetic model of the real time simulation device; the real time simulation device simulates subway vehicle loading conditions and subway traction system net voltage conditions in real time; a traction control device sends a traction control signal to the real time simulation device, thus driving the subway vehicle model in the real time simulation device to run in a testing requirement state; the host monitoring device adjusts the parameters of the subway vehicle electric model and the subway vehicle kinetic model of the real time simulation device and the net voltage conditions, thus carrying out a net voltage interruption test, a net voltage mutation test or a net voltage fluctuation test; the host monitoring device determines whether the net voltage interruption, mutation or fluctuation test have succeeded or not.

A system and method for generating a worst case current waveform for testing of integrated circuit devices are provided. Architectural analysis of an integrated circuit device is first performed to determine an initial worst case power workload to be applied to the integrated circuit device. Thereafter, the derived worst case power workload is applied to a model and is simulated to generate a worst case current waveform that is input to an electrical model of the integrated circuit device to generate a worst case noise budget value. The worst case noise budget value is then compared to measured noise from application of the worst case power workload to a hardware implemented integrated circuit device. The worst case current waveform may be selected for future testing of integrated circuit devices or modifications to the simulation models may be performed and the process repeated based on the results of the comparison.

The invention relates to a method for building a horizontal layered soil electrical model, which comprises the steps of building a composite layered soil model according to magnetotelluric three-dimensional inversion soil resistivity data, selecting the earth surface potential to act as a fitting index, fitting the earth surface potential of a composite model acquired by using a finite element method and the earth surface potential of a horizontal model deduced by using a Green function method by adopting a least square method so as to acquire an objective function of the horizontal layered soil electrical model, carrying out optimization solving on the objective function by adopting a genetic algorithm, acquiring a soil resistivity parameter and the corresponding layer depth of each layer in the horizontal layered soil electrical model, and thus realizing conversion from composite layering to horizontal layering of the model. The method provided by the invention reduces the complexity of the model, improves the reliability of the model, and can provide more accurate soil resistivity model data for analysis of an earth electrode.

Techniques for determining a formation property by simplifying various two-geological-layer or multi-geological-layer models into a multi-electrical-layer model. A volume fraction of a layer in a multi-electrical-layer model is determined for an anisotropic region (sliding window) of the formation. The multi-electrical-layer electrical model includes a relative-lower-resistivity layer and a relative-higher-resistivity layer. A high-resolution resistivity measurement is used in the determination and resistivities for the relative-lower-resistivity layer and for the relative-higher-resistivity layer based on the volume fraction and bulk resistivity measurements of the anisotropic region are determined. The formation property is based on the volume fraction, the resistivity of the relative-lower-resistivity layer, the resistivity of the relative-higher-resistivity layer, a total porosity of the anisotropic region, and bulk resistivity measurements of the region.

The invention provides a high-speed detection method and device for terahertz. The high-speed detection device comprises a THzQWP (THz Quantum Well Photodetector) for directly carrying out strength detection on the terahertz and a trans-impedance amplifying circuit for supplying a bias voltage to the THzQWP and converting light current generated by the THzQWP into voltage signals. For conveniently designing the parameters of the trans-impedance amplifying circuit, the invention provides a small-signal lumped electrical model of the THzQWP. The small-signal lumped electrical model is formed by connecting a capacitor Cq with a bypass differential resistor Rd and a light current source Is in parallel. The trans-impedance amplifying circuit comprises an operational amplifier, a compensation capacitor CF and a trans-resistor RF; the inverse-phase input end of the operational amplifier is connected with one end of the THzQWP; the non-inverting input end of the operational amplifier is connected with the bias voltage; the trans-resistor RF is connected with the output end and the inverse-phase input end of the operational amplifier; the compensation capacitor is connected in parallel with the trans-resistor; and the other end of the THzQWP is connected with the ground. The high-speed detection device provided by the invention can supply the very low working bias voltage for the THzQWP, and converts the light current signals of the THzQWP to the voltage signals simultaneously, so that the follow-up circuit link treatment is facilitated.

The invention discloses a two-dimensional thermoelectric refrigerator electrical model with non-uniform substrate temperature being considered. The two-dimensional distributed electrical model considering the substrate temperature distribution and the temperature distribution of thermoelectric cooler (TEC) in the direction of height, an electrical model based on Hspice is established, based on the duality of the multi-stage TEC chain and the thermoelectricity in electrical series and thermal parallel connection; the influence of the temperature distribution on the TEC parameters is revised through multiple iterations and the temperature distribution can be provided finally. The two-dimensional thermoelectric refrigerator electrical model with the non-uniform substrate temperature being considered according to the influence of the substrate temperature distribution on the two-dimensional temperature control parameters, proposes a distributed electric network model which can accurately estimate the cooling ability of the TEC, and provides a feasible heat dissipation solution for improving the reliability of the chip and the performance of the system.