34 results about "Equivalent circuit analysis" patented technology

The invention discloses a pipeline safety pre-warning and leakage monitoring alarm method. The alarm method can carry out pre-warning timely in the cases of external pipeline damaging events, external pipeline corrosion, internal corrosion, local stray current corrosion, anticorrosive coating strip-off corrosion and pipe stock mechanical abrasion reduction. Once a sudden event changes too fast, pre-warning is not carried out in time, and thus pipeline leakage is caused, the alarm method also can discover the situation and send an alarm, as core algorithm software runs in an upper host and a lower host and is used for processing real-time and static data, the pipeline safety pre-warning and leakage alarm are realized. The core algorithms include data acquisition requirements, an exception identifier, a simple equivalent circuit analytical method, a pipeline external damage and corrosion pre-warning positioning method, a pipeline internal corrosion pre-warning and positioning method, a local stray current corrosion pre-warning and positioning method, a pipe stock mechanical abrasion reduction pre-warning and positioning method, and a pipeline leakage monitoring alarm positioning method, the methods are realized by using the exception identifier.

The invention discloses a parameter extraction method for InP HBT small-signal models, which mainly solves the problems of the prior art, i.e. complex extraction process and inaccurate extraction results. The technical scheme of the invention is as follows: an open circuit soldering point structure and a short circuit soldering point structure are adopted to analyze an equivalent circuit to extract parasitic parameters; a collector open circuit state is adopted to analyze the equivalent circuit to extract external resistance parameters; a circuit network theory is utilized to analyze the scattering parameter S, impedance parameter Z and admittance parameter Y of the intrinsic part of an InP HBT device; and a layer-by-layer stripping method is adopted to determine a fixed expression for each intrinsic model parameter to extract intrinsic parameters. The parameter extraction method has the advantage of accurate, rapid and visual parameter extraction. A simulation result shows that a small-signal model result extracted by the method can perfectly fit the scattering parameter S of an actual device-testing result and can be used for directing circuit design and the determination of a large-signal model peripheral circuit.

The invention discloses a long-distance wireless charging LCC-S topological parameter design method. The method comprises the steps that (1) target parameters are set; (2) calculating the minimum efficiency required to be satisfied by the resonator according to design requirements; (3) establishing an LCC-S equivalent circuit based on the mutual inductance equivalent model, and analyzing to obtaina constraint relationship between circuit parameters and each branch current, input power, output power and efficiency; (4) designing magnetic coupling mechanism parameters under a long-distance transmission condition; (5) designing primary side compensation inductance (capacitance) parameters; (6) calculating compensation inductance loss, eddy current loss, hysteresis loss and capacitance loss;(7) calculating the resonator efficiency, comparing the resonator efficiency with a target set value, If the designed resonator efficiency is greater than or equal to the target set efficiency, determining that the designed parameter value meets the target parameter setting requirement; otherwise, returning to the step (4) to redesign the parameters. The method is used for promoting the universality and economy of wireless power transmission technology application.

The invention provides an equivalent circuit-based transistor reliability representation method, which comprises the following steps: (S1) determining an equivalent circuit of a transistor according to the transistor type; (S2) determining the type and the size of stress applied to an accelerated lifetime test and determining a sensitive parameter degradation model in the equivalent circuit; (S3) carrying out the accelerated lifetime test on the transistor; (S4) regularly collecting testing data of the transistor, extracting a sensitive parameter of the equivalent circuit to obtain a variation relationship of the sensitive parameter of the equivalent circuit along with the stress and time; (S5) fitting undetermined constants in the sensitive parameter degradation model to obtain a complete sensitive parameter degradation model and a complete equivalent circuit; and (S6) carrying out failure mechanism analysis and reliability analysis on the transistor. The equivalent circuit-based transistor reliability representation method can be used for simulating influences of a device failure mechanism on circuit performance, analyzing the failure mechanism of the transistor and guiding process improvement; the performance degradation and the failure time of the transistor can also be predicted; and the reliability test time is shortened.

The invention designs an electromagnetic transient equivalent modeling method for an input-series and output-parallel cascaded power electronic transformer with double active bridges. The core technical scheme of the invention is as follows: 1, carrying out discretization equivalence on a switch group, a capacitor, an inductor and a primary / secondary side of a transformer to form a cascaded PET adjoint circuit; 2, listing a node admittance equation of a single H-bridge-DAB module, eliminating internal nodes by utilizing a rapid nesting simultaneous solving algorithm to obtain an equivalent circuit only containing four nodes, and meanwhile, reserving admittance information of the internal nodes; 3, performing equivalent simplification between PET modules to obtain an equivalent circuit onlycontaining four nodes of a plurality of H-bridge-DAB modules, and popularizing the equivalent circuit to three phases; 4, integrally solving by using electromagnetic transient simulation software toobtain equivalent four-terminal voltage and current of each phase; and 5, inversely solving and eliminating the voltage and current of the nodes, and updating equivalent parameters of the capacitor, the inductor and the transformer branch at the current moment.

A capacitor simulation method and nonlinear equivalent circuit model enabling dynamic simulation of nonlinear characteristics when direct-current voltage is applied with high precesion are easily provided using a simple configuration. An equivalent circuit of a capacitor is represented using a series circuit of passive circuit elements. Characteristic change ratios of the passive circuit elements when a direct-current voltage is applied are expressed as an approximate function on the basis of an actually measured value. A reference voltage is referred to by control current sources connected in parallel to the passive circuit elements. The characteristic change ratios are calculated in accordance with the reference voltage Vref. Difference currents are generated on the basis of the characteristic change ratios and currents flowing when no direct-current voltage is applied, they are caused to flow concurrently with the currents flowing when no direct-current voltage is applied, and thus the nonlinear characteristics are simulated.

The invention discloses a building method for a common mode EMI model and an equivalent circuit of a complete train of a high-speed motor train unit. The method comprises the steps of establishing anEMI model graph of the complete train; establishing an EMI model graph of a traction converter; establishing an equivalent circuit graph of a common mode EMI loop caused by a potential point A of a rectifier bridge of the high-speed motor train unit, and then according to the equivalent circuit, calculating out a conducted EMI current; and establishing the equivalent circuit after passing the converter, and then according to the equivalent circuit, calculating out the conducted EMI current. The model and the equivalent circuit in the method describe common mode EMI characteristics of the complete train of the high-speed motor train unit, wherein the common mode EMI characteristics include common mode ground capacitance distribution, a cable high-frequency model, and high-frequency parasitic characteristics of transformer primary and secondary sides. The model and the equivalent circuit predict the common mode EMI characteristics of the complete train and serve as technical means of research on common mode EMI of the high-speed motor train unit; the equivalent circuit obtains a mathematic expression of a common mode EMI current; and the expression predicts the magnitude of the common mode EMI current of the complete train.

The present invention discloses a preparation method and applications of a human odor binding protein sensor of a nano-pore array. According to the present invention, the nano-pore array prepared through a standard two-step anode oxidization method is used, the nano-pore array is treated with 2-carboxyethylphosphonic acid so as to immobilize human odor binding protein, and the human odor binding protein immobilizing nano-pore array is fixed in a designed reaction dish so as to obtain the sensor; the electrochemical impedance testing method and the equivalent circuit analysis method are used to immobilize the human odor binding protein onto the nano-pore array so as to be used for detecting disease-related fatty acid (docosahexaenoic acid) molecules and aldehyde molecules (benzaldehyde); and the constructed electrochemical sensor has characteristics of high detection sensitivity and low detection lower limit.

The invention discloses an interleaved non-isolated switched capacitor network high-gain soft switching converter and a control method thereof. According to the method, a resonance branch shared by two boost circuits contained in the converter is found through equivalent circuit analysis on the basis of hard switching topology of the high-gain direct-current converter of the interleaved non-isolated diode capacitor network; ZVS switching-on of the two switching tubes and ZCS switching-off of all diodes are achieved by inserting a resonant inductor into the branch and connecting resonant capacitors to the two ends of the switching tubes in parallel. The quasi-resonance soft switching circuit design method has certain universality, is suitable for a high-gain direct-current converter of an interleaved non-isolated switched capacitor network, and has a wide application prospect in a new energy distributed power generation system.

The invention discloses a nonlinear equivalent circuit of a PIN diode, which comprises a parasitic resistor, a P-I junction equivalent circuit unit, an intrinsic region I equivalent circuit unit, an I-N junction equivalent circuit unit and a reverse capacitor, wherein the parasitic resistor, the P-I junction equivalent circuit unit, the region I equivalent circuit unit and the I-N junction equivalent circuit unit are sequentially connected in series, and the reverse capacitor is connected in parallel with the P-I junction equivalent circuit unit, the region I equivalent circuit unit and the I-N junction equivalent circuit unit. The invention realizes the simulation of an RF / MW circuit comprising the PIN diode. The invention is especially suitable for the analysis of the harmonic wave and the intermodulation distortion of the RF / MW circuit of the PIN diode.

A new optical ultrasonic analysis transducer is described. The device includes a new detection means for the reflected ultrasound signal. The detector may be incorporated into a microchip design. The detector is compatible with a variety of material and design geometries that may be optimized for the particular application. Versions of the device may optionally include both excitation and receiving elements on the same device or these elements may be separate. Example designs are shown with applications to continuous wave ultrasound analysis useful for example in Doppler fluid flow measurements. Other designs are shown with multiple arrays and multiple excitation transducers to allow flexible three-dimensional imaging apparatus to be built. An equivalent circuit analysis of the frequency response and signal sensitivity provides means to customize material selection and other design parameters for particular applications.

The invention discloses a ground wire energy harvesting method for an overhead transmission line. The method comprises the steps that the parameter information of a target overhead transmission line is collected, and the energy harvesting parameter information is calculated; all possible ground wire energy harvesting alternatives of the target overhead transmission line are acquired; the equivalent circuits of the ground wire energy harvesting alternatives are derived; a formula for calculating the maximum power of the ground wire energy harvesting alternatives is derived; the magnitude of theenergy harvesting power of the ground wire energy harvesting alternatives is analyzed under different position relations between a ground wire and a wire; and the best ground wire energy harvesting scheme is selected as the final ground wire energy harvesting method. According to the invention, the ground wire energy harvesting scheme of the transmission line with double insulation ground wires is analyzed; the equivalent circuits of energy harvesting are derived; the energy harvesting power calculation formula is analyzed; the analysis method of the energy harvesting scheme by the spatial position relationship between the ground wire and the wire is proposed to guide the optimization of the ground wire energy harvesting scheme; the problem of selecting the energy harvesting scheme is solved; and the method has the advantages of simple principles, high operability, high reliability, scientific rationality, and easy implementation.

The invention discloses an equivalent circuit analysis model for influence of a magnetic field coil on a space field of a bounded wave simulator. The equivalent circuit analysis model is mainly composed of a current source I, an equivalent capacitor C1 formed between an upper pole plate and a lower pole plate of the bounded wave simulator, an equivalent capacitor C2 formed at the part, corresponding to an external coil, of the upper pole plate of the bounded wave simulator, an equivalent capacitor C3 formed at the part, corresponding to the external coil, of the lower pole plate of the boundedwave simulator, a coil inductor L and a terminal matching load R of a bounded wave simulator loop. The equivalent circuit analysis model is simple and visual, the waveform characteristics of the space electric field can be effectively reflected, physical interpretation of electric field waveform distortion is given, the electric field waveform change rule after a coil type pulse magnetic field simulator and the bounded wave simulator are combined can be conveniently analyzed, and therefore the application range of an effect test is determined.

A new optical ultrasonic analysis transducer is described. The device includes a new detection means for the reflected ultrasound signal. The detector may be incorporated into a microchip design. The detector is compatible with a variety of material and design geometries that may be optimized for the particular application. Versions of the device may optionally include both excitation and receiving elements on the same device or these elements may be separate. Example designs are shown with applications to continuous wave ultrasound analysis useful for example in Doppler fluid flow measurements. Other designs are shown with multiple arrays and multiple excitation transducers to allow flexible three-dimensional imaging apparatus to be built. An equivalent circuit analysis of the frequency response and signal sensitivity provides means to customize material selection and other design parameters for particular applications.

The invention provides a piezoelectric gyro equivalent circuit capable of considering energy loss. The piezoelectric gyro equivalent circuit capable of considering energy loss comprises a non-resonant part equivalent circuit and a resonant part equivalent circuit, wherein the resonant part equivalent circuit comprises n parallel resonant circuits, and n is a positive integer which is greater than or equal to 1; each parallel resonant circuit consists of a dynamic capacitor, a dynamic inductor and a dynamic resistor; the non-resonant part equivalent circuit consists of a static capacitor, a serial resistor and a parallel resistor. When n resonance modes are required to be simulated by a piezoelectric gyro, only n parallel resonant circuits are required to be added. According to the equivalent circuit disclosed by the invention, the problems of a plurality of resonance modes and energy loss of the piezoelectric gyro can be described precisely, and precise numerical values can be provided for simulation of the piezoelectric gyro.

The invention relates to an equivalent circuit of a floating-type fractional-order memristor and a use method thereof. The technical scheme is as follows: the equivalent circuit of the floating-type fractional-order memristor applies an excitation voltage v (t) and passes through an amplification module 8. The functions of 23 modules, such as a voltage controlled phase shifter (6) and a frequency / voltage converter (23), can accurately simulate the electrical characteristics of the fractional-order memristor with high accuracy, and simultaneously ensure that the currents passing through the terminal A and the terminal D of the equivalent circuit of the floating-type fractional-order memristor are equal; the fractional-order memristor order control signal Alpha 'introduced can change the order of the fractional-order memristor, and the fractional-order memristor state variable initial value control signal x0' introduced can change the fractional-order memristor state variable initial value. The fractional-order and fractional-order memristor state variable initial values of the floating-type fractional-order memristor equivalent circuit can be easily adjusted and controlled, and theterminals A and D of the equivalent circuit can be arbitrarily connected with the components of other circuits when in use.

The invention discloses a modeling method suitable for an equivalent circuit of an electro-acoustic longitudinal vibration transducer. An overall equivalent circuit of the electroacoustic longitudinalvibration transducer comprises a first equivalent circuit of an alternating current coil, a second equivalent circuit of a series circuit of a direct current bias coil and a linear direct current power supply, a mechanical equivalent impedance network and a three-winding equivalent transformer. According to the method, by constructing the first equivalent circuit, the second equivalent circuit, the mechanical equivalent impedance network and the three-winding equivalent transformer respectively to obtain the integral equivalent circuit finally by integration, the actual winding method of thethree-winding equivalent transformer does not need to be considered, meanwhile, by considering the influence of the second equivalent circuit on the impedance of the electro-acoustic longitudinal vibration transducer, the method has certain universality on the electro-acoustic longitudinal vibration transducer, and the impedance characteristic of the electro-acoustic longitudinal vibration transducer can be well reflected, so that the response of the overall equivalent circuit is relatively accurate, and further, guidance is provided for impedance matching between the power amplifier and the electro-acoustic longitudinal vibration transducer.

A state determination apparatus includes: electrodes configured to apply AC signal to a mixture; a measurement unit configured to measure an impedance of the mixture for every frequency of the AC signal based on a response signal flowing through the mixture when the AC signal is applied; a setting unit configured to set an equivalent circuit including one or a plurality of parallel circuit(s) based on element(s) corresponding to electrical component(s) of a solid matter; a calculating unit configured to calculate a parameter of the parallel circuit by executing an equivalent circuit analysis for approximating impedance of the equivalent circuit to the impedance of the mixture; and a derivation unit configured to derive an index for specifying a state of the mixture based on the parameter of the parallel circuit.

The invention discloses an interleaved non-isolated switched capacitor network high-gain soft switching converter and a control method thereof. The method finds the converter through equivalent circuit analysis on the basis of the hard switching topology of the interleaved non-isolated diode capacitor network high-gain DC converter. In the resonant branch shared by the two boost circuits included in the circuit, by inserting a resonant inductor in the branch and connecting a resonant capacitor in parallel at both ends of the switching tube, the ZVS of the two switching tubes is turned on, and the ZCS of all diodes is turned off. The quasi-resonant soft switching circuit design method of the present invention has certain versatility, is suitable for a type of interleaved non-isolated switched capacitor network high-gain DC converter, and has broad application prospects in new energy distributed power generation systems.

An inductor simulation method and nonlinear equivalent circuit model enabling dynamic simulation of nonlinear characteristics when a direct current is superimposed with high precision. An equivalent circuit of an inductor is represented using a series circuit of passive circuit elements. Characteristic change ratios of the passive circuit elements when a direct current is superimposed are expressed as an approximate function on the basis of actually measured values. A reference current measured by each of voltage source models is referred to by a control voltage source connected in series to the passive circuit elements. The characteristic change ratios are calculated in accordance with the reference current Iref. Difference voltages are generated on the basis of the characteristic change ratios and voltages occurring when no direct current is superimposed, they are superimposed on the voltages VL1 and VR1 occurring when no direct current is superimposed, thereby simulating the nonlinear characteristics.

The invention discloses an equivalent circuit, an analysis method and a system of a double-beam power amplifier behavior model. The equivalent circuit comprises a nonlinear crosstalk coupler, a first synthesis filter, a second synthesis filter and a linear crosstalk coupler; the first output of the nonlinear crosstalk coupler is connected to the input of the first synthesis filter, and the first The output end of the synthesis filter is connected to the first input end of the linear crosstalk coupler, the second output end of the nonlinear crosstalk coupler is connected to the input end of the second synthesis filter, and the output end of the second synthesis filter is connected to the linear crosstalk The second input of the coupler is connected. The equivalent circuit includes a nonlinear crosstalk coupler, a linear crosstalk coupler and a comprehensive filter that characterizes memory effects and nonlinearity. Satellite communication multi-beam antenna technology provides theoretical reference and technical support to facilitate linear and nonlinear crosstalk compensation.

The invention discloses a parameter extraction method for InP HBT small-signal models, which mainly solves the problems of the prior art, i.e. complex extraction process and inaccurate extraction results. The technical scheme of the invention is as follows: an open circuit soldering point structure and a short circuit soldering point structure are adopted to analyze an equivalent circuit to extract parasitic parameters; a collector open circuit state is adopted to analyze the equivalent circuit to extract external resistance parameters; a circuit network theory is utilized to analyze the scattering parameter S, impedance parameter Z and admittance parameter Y of the intrinsic part of an InP HBT device; and a layer-by-layer stripping method is adopted to determine a fixed expression for each intrinsic model parameter to extract intrinsic parameters. The parameter extraction method has the advantage of accurate, rapid and visual parameter extraction. A simulation result shows that a small-signal model result extracted by the method can perfectly fit the scattering parameter S of an actual device-testing result and can be used for directing circuit design and the determination of a large-signal model peripheral circuit.

A uniformity output device for outputting a uniformity of particles in a slurry, in which an insoluble solid matter is mixed in liquid, includes: a pair of electrodes configured to apply AC voltage to the slurry; a measurement unit configured to measure impedance of the slurry on the basis of the response current flowing through the slurry when AC voltage with changing frequency is applied to the slurry; and a processing unit configured to determine the uniformity by executing a particle equivalent circuit analysis with a parallel circuit formed of a resistor and a capacitor as an element on the basis of the impedance measured by the measurement unit in accordance with the frequency.

The invention belongs to the technical field of testing of semiconductor devices, and particularly relates to a dielectric temperature coefficient corrected deep energy level transient spectrum testing method. According to the method, the equivalent circuit of the DLTS test is combined, the influence of the insulation layer capacitance in the MIS structure on the DLTS signal is analyzed, then the DLTS test data is analyzed, the influence factor alpha of the insulation layer capacitance in the MIS structure is calculated, then the original DLTS signal spectrum is corrected according to the DLTS spectral line data and the influence factor, and the accurate DLTS signal spectrum is obtained. According to the invention, the problem that the existing DLTS test is inaccurate when the MIS structure is made of a material with dielectric constant dependent on temperature is solved, and finally, the defect level, the sinking concentration and the interception area of the MIS structure are accurately obtained.

The invention discloses an equivalent circuit, an analysis method and an analysis system of a dual-beam power amplifier behavior model. The equivalent circuit comprises a nonlinear crosstalk coupler,a first comprehensive filter, a second comprehensive filter and a linear crosstalk coupler; the first output end of the nonlinear crosstalk coupler is connected with the input end of the first comprehensive filter, the output end of the first comprehensive filter is connected with the first input end of the linear crosstalk coupler, and the second output end of the nonlinear crosstalk coupler is connected with the input end of the second comprehensive filter. The output end of the second comprehensive filter is connected with the second input end of the linear crosstalk coupler. The equivalentcircuit comprises a nonlinear crosstalk coupler, a linear crosstalk coupler and a comprehensive filter representing the memory effect and nonlinearity, the complexity is low, the application in practical engineering is facilitated, theoretical reference and technical support are provided for further research of 5G large-scale MIMO and low-earth-orbit satellite communication multi-beam antenna technologies. Linear and nonlinear crosstalk compensation can be carried out conveniently.