95 results about "Ohmic Resistance" patented technology

The invention discloses a battery pack equalization control method and system based on multidimensional state mapping, and the method comprises the steps: obtaining terminal voltage data, working current data and surface temperature data of each single battery in a target battery pack; calculating an ohm internal resistance value and a polarization impedance value of each single battery; calculating an impedance growth rate; according to the impedance growth rate and the surface temperature data, a health state value is determined, and an aging weighting coefficient is determined; determining a polarization safety coefficient of each single battery based on the polarization impedance value; calculating a state-of-charge value of each single battery in the target battery pack, and determining a balance demand deviation degree; determining a basic equalization duty ratio of each single battery according to the equalization demand deviation degree; correcting the basic balance duty ratio to generate a target pulse width modulation duty ratio; and according to the target pulse width modulation duty ratio, controlling equalization circuits connected to the two ends of each single battery to be switched on. The battery pack equalization control efficiency is improved.

The invention discloses a low-temperature exposed lithium battery aging damage diagnosis method based on electrochemical nondestructive characterization, which comprises the following steps: firstly, acquiring electrochemical response data of a to-be-tested battery through electrochemical impedance spectroscopy (EIS) test and incremental capacity analysis (ICA); secondly, key characteristic parameters capable of representing ohmic internal resistance, charge transfer resistance and electric double-layer capacitance of the battery and phase change peak position, peak area, half-peak width and the like are extracted; and then, training a joint prediction model based on machine learning by using the extracted multi-dimensional features to judge whether the to-be-detected battery is subjected to over-low-temperature exposure or not and judge the current aging damage degree of the to-be-detected battery. According to the method, unique aging paths introduced by normal aging and low-temperature exposure can be effectively distinguished through a nondestructive testing means, accurate'traceability 'of historical damage of the battery and quantitative evaluation of the current state are achieved, and reliable technical support is provided for intelligent decision making of a battery management system (BMS), battery safety early warning and echelon utilization.

The utility model discloses a miniature ozone electrode module structure, relates to the technical field of miniature ozone generation, and is used for solving the problems of complex structure, large volume and low ozone generation efficiency of an ozone generator at the present stage. According to the utility model, the polar plates directly act in an aqueous solution through the ozone electrode module with a direct insertion shell structure, generated ozone does not directly act in the shell, the overall service life is prolonged, and meanwhile, a two-cathode and one-anode clamping type polar plate structure is adopted, so that the distance between the polar plates is controlled, and bubbles generated between the polar plates are effectively separated; meanwhile, the reaction spacing can be reduced as much as possible, the ohmic resistance of the reaction is reduced, reactants can be provided for the electrode reaction in time, the electrolytic mass transfer efficiency is also improved, the electric field distribution around the anode is more uniform, and meanwhile, the equipment is miniaturized and integrated, so that the production efficiency is improved. The method is suitable for application scenes with high requirements for space and cost.

The invention discloses a composite solid positive electrode, a battery cell, a single battery and electric equipment. The positive electrode is composed of a current collector, a positive active material, an electronic conductive agent, a solid electrolyte and an interface modifier. Wherein the positive active material is used for providing a lithium source; the electronic conductive agent is used for reducing ohmic internal resistance and polarization; the solid electrolyte is used for transmitting ions, and the interface modifier is used for further reducing internal resistance and polarization. When the solid electrolyte is a composite electrolyte of sulfide and a polymer, the infiltration problem of a solid-solid interface and the deformation problem caused by charging and discharging can be solved due to the existence of the interface modifier. The positive electrode material can be applied to battery systems such as liquid, solid and alkali metal batteries.

The invention provides a battery state estimation method and system and a medium, and relates to the technical field of a battery management system.The method comprises the steps that a second-order RC equivalent circuit model is established, and parameters such as ohm internal resistance, polarization internal resistance and polarization capacitance are identified online through an RLS with a forgetting factor; constructing a microscopic state SRCKF channel and a macroscopic parameter SRCKF channel, performing real-time correction on an SOC influence factor and a current influence factor based on a filtering performance index, adaptively adjusting process noise and measurement noise covariance according to sub-channel logic, and introducing cross-channel cooperative self-adaption; the state channel outputs SOC and terminal voltage estimated values, the parameter channel outputs dynamic internal resistance and maximum available capacity, and SOH is calculated and output. The method improves the estimation precision and robustness under the working conditions of low SOC and large current, has good numerical stability, and is suitable for monitoring the whole life cycle of the power battery.

Instrumented nut, clamping sleeve, clamping device and method for tightening such a nut. The invention relates to an instrumented metal nut (10b) comprising a tubular body having a polygonal drive surface (14). The nut comprises, on at least one annular portion (34) of its outer surface: an electrically insulating layer (36) applied to the annular portion; a piezoresistive conductive polymer (38) whose ohmic resistance varies according to a stress exerted during tightening of the nut on a threaded fastener, said conductive polymer being applied to the electrically insulating layer; and at least two electrodes (40). Figure for the abstract: Figure 2

The application provides a power battery thermal runaway diagnosis method and system based on a hybrid prediction framework, sample data at time t of the battery is collected, and the sample data is preprocessed; a first-order equivalent circuit model of the power battery is constructed, and the least square method is used to identify the voltage, ohmic resistance, polarization resistance and polarization capacitance in the initial state; a SOC estimation model is constructed by using a current integration method; a battery internal temperature estimation model is constructed based on the internal Joule heat of the power battery and the heat exchange heat of the external environment; the standardized data in step S2 are input into a recurrent neural network GRU for training to obtain estimated sample data at time t+1; state space models are respectively constructed based on the SOC estimation model and the battery internal temperature estimation model; the estimated sample data is input into an adaptive unscented Kalman filter AUKF model as observation at time t+1 based on the state space models, and prediction data at time t+1 is calculated; and the thermal runaway is predicted through the prediction data.

The application discloses a composite electrolyte buffer layer for solid oxide electrolysis cell and a preparation method, and relates to the technical field of SOFC electrolyte. The composite electrolyte buffer layer is formed by sequentially sputtering electrolyte sputtering dense layer I, electrolyte sputtering dense layer II and anode sputtering layer on the surface of the electrolyte layer of the solid oxide electrolysis cell. The thickness of the electrolyte sputtering dense layer I is 10 nanometers to 1 micrometer, the thickness of the electrolyte sputtering dense layer II is 50 nanometers to 500 nanometers, and the thickness of the anode sputtering layer is 5 nanometers to 30 nanometers. The composite electrolyte nanometer buffer layer prepared by the magnetron sputtering method has the advantages of blocking electrons, improving open circuit voltage, enhancing ion conductivity to reduce ohmic resistance, enhancing chemical compatibility and thermal matching with electrodes to improve long-term stability, etc. The composite electrolyte nanometer buffer layer solves the problem of internal leakage of the traditional low-temperature electrolyte, improves the open circuit voltage to above 1.00V (600 DEG C), improves the output power and stability of the solid oxide electrolysis cell, and expands the application range of the solid oxide electrolysis cell.

The application discloses a kind of lithium battery's residual life prediction method, belong to battery life prediction technical field.The application first divides lithium battery charging process into constant-current section, transition section and constant-voltage section, collects voltage and current signal in each section, obtains equivalent transient impedance spectrum by Fourier transform, and calculates interface aging factor based on charge transfer resistance, ohmic resistance and double-layer capacitance;Then respectively extract the features in each section to form the feature vector in each section, derive to obtain the feature vector between sections, splice the three feature vectors in each section corresponding to similar data and two feature vectors between sections to form feature splicing vector;Finally, using the feature weighted distribution type BP model, the feature splicing vector of equivalent transient impedance spectrum and interface aging factor is processed, and the residual life prediction value is output.The application improves the prediction accuracy significantly by charging segmented feature extraction, inter-feature extraction and weighted model optimization.

The application provides an energy flow modeling analysis method of an alkaline water electrolysis hydrogen production system, which comprises the following steps: for the stack component, based on an electrochemical reaction mechanism equation and an Ohm's law, defining a reversible voltage and an activation overvoltage as a voltage source in an electrolysis cell unit, defining an Ohm's resistance according to an Ohm's overvoltage, connecting different circuit elements to obtain an electrochemical energy flow model of the stack; establishing a heat transfer energy flow model of a gas-liquid separator, the stack component, a mixer and a heat exchanger, connecting nodes with the same temperature, and establishing a system overall heat transfer energy flow model; taking an ambient temperature and a cold fluid inlet temperature as boundary conditions, and according to the electrochemical energy flow model of the stack component, the system overall heat transfer energy flow model and corresponding constraint conditions, combining system operation parameters and system structure parameters to solve the model, and obtaining an alkaline water electrolysis hydrogen production system operation analysis result. The energy flow modeling analysis method of the alkaline water electrolysis hydrogen production system provided by the application realizes the cross-scale unified modeling and analysis of the alkaline water electrolysis hydrogen production system by establishing the heat transfer energy flow model of the external system and the electrochemical energy flow model of the internal process of the stack.

The application discloses a kind of intelligent determination method and device of battery charging demand current, the method includes: based on the historical open-circuit voltage parameter of pre-set battery and historical ohmic resistance parameter, determine the current open-circuit voltage parameter of battery and current ohmic resistance parameter;Based on current open-circuit voltage parameter and current ohmic resistance parameter, calculate the current charging current limit of battery;Based on current charging current limit, determine the current charging demand current of battery. Visible, the charging current limit of battery can be calculated in real time by implementing the application, to evaluate the charging limit capacity of battery, and determine the charging demand current of battery, so that the reliability and accuracy of the charging demand current determined can be improved, and then the vehicle battery can be reliably and accurately charged, so that the charging safety and charging efficiency of vehicle battery can be improved, to realize the good charging effect of vehicle battery.

The invention relates to a method for de-exciting a rotor winding of a rotor of an electric machine (2) of a motor vehicle (1), the electric machine comprising a stator and a rotor mounted rotatably relative to the stator, the rotor having a rotor winding for generating a rotor magnetic field, an active rectifier being arranged on the rotor side, the rectifier comprises at least one field effect transistor which can be actuated by means of an actuation voltage, the rectifier electrically connects a voltage source present on the rotor side to the rotor winding, by means of which an alternating voltage provided by the voltage source can be converted into a direct voltage, the field effect transistor or at least one of the field effect transistors is brought into an operating state, in which the respective field effect transistor forms an ohmic resistance, by means of a control voltage, and the energy stored in the rotor winding causes a current to flow through the at least one field effect transistor forming the ohmic resistance, at least a portion of the energy is converted into thermal energy.

The invention relates to the field of batteries, in particular to an electrolyte and a battery. According to the electrolyte, a solvent formula with a specific proportion is mixed with an additive for use, the additive forms a solid electrolyte interface film on the surface of an electrode prior to the solvent in a battery activation stage, and the first additive can be in contact with trace water in the electrolyte preferentially, so that the content of HF in a circulation process is reduced; meanwhile, other additives can be matched to form a stable CEI film rich in inorganic components on the surface of an electrode, so that the side reaction on the surface of the electrode is reduced, the cycle life of the battery is prolonged, meanwhile, due to the addition of the low-viscosity solvent, the ionic conductivity in the electrolyte is improved, the ohmic resistance of the battery is reduced, and the service life of the battery is prolonged due to the uniformity of the CEI film. And due to low interface impedance, the electrolyte can meet the working condition under high magnification.

The utility model discloses a variable-frequency controller and a refrigeration device, and relates to the technical field of variable-frequency control, and the variable-frequency controller comprises a power supply module, a control module and a 0-ohm resistor. The power supply module is used for carrying out voltage reduction and rectification on alternating current so as to supply power to the control module, and a 0-ohm resistor is arranged between the control module and the ground and is used for isolating the control module from the ground when electromagnetic interference exists. Therefore, the zero-ohm resistor is arranged between the control module and the ground, the reference ground of the control module is isolated from the ground when electromagnetic interference exists, the electromagnetic interference is effectively reduced, and normal operation of the refrigeration device is ensured.

The invention provides an abnormal resistance positioning method, electronic equipment and a storage medium. The method comprises the following steps: acquiring at least two groups of current and voltage data; calculating first resistance data according to the at least two groups of current and voltage data, wherein the first resistance data comprises the total internal resistance of the direct current side and the direct current resistance of each battery cell; acquiring second resistance data, wherein the second resistance data comprises the ohmic internal resistance of each battery cell; calculating connection impedance according to the first resistance data and the second resistance data; an abnormal resistance is determined based on the first resistance data, the second resistance data, and the connection impedance. Therefore, the total internal resistance of the direct current side and the direct current internal resistance of each battery cell are calculated through at least two groups of current and voltage data, and the connection impedance is calculated by combining the directly obtained ohmic resistance of each battery cell, so that the accurate distinguishing of various resistance data is realized, and the type and the position of the abnormal resistance can be effectively positioned; and rapid troubleshooting of maintenance personnel is facilitated, and the maintenance cost is reduced.

To provide a dry electrode having high dispersibility of a conductive material.SOLUTION: The dry electrode obtained by the manufacturing method according to the present disclosure has high dispersibility of the conductive material in the electrode active material layer. Accordingly, when the content of the conductive agent in the electrode is constant, the internal resistance of the electrode active material layer and the interfacial resistance with the current collector are reduced as the dispersibility is higher. Also, in a case in which the dry electrode having high dispersibility is applied to a battery, since ohmic resistance is reduced during the operation of the battery, a voltage drop may be improved, and high output efficiency may be improved. In a case in which the dispersibility of the conductive agent is extremely poor, the deterioration of the electrode active material may be non-uniform depending on the position in the electrode, which is disadvantageous for the life characteristics of the battery. In addition, the evaluation tool according to the present invention can confirm the dispersibility of the conductive material in the electrode as a quantitative value.SELECTED DRAWING: Figure 1

This invention belongs to the field of electrochemical deoxygenation technology, specifically relating to an electrochemical oxygen atmosphere control system and method. The system, from bottom to top, includes a porous bottom cover, a first hydrophobic and breathable membrane, an oxygen-consuming cathode, a liquid-conducting diaphragm, an oxygen-evolving anode, a second hydrophobic and breathable membrane, and a porous top cover. Each component layer forms a zero-gap contact through the clamping force of the outer shell, enabling the device to achieve an ultra-thin thickness. The liquid-conducting diaphragm has a transverse liquid-conducting groove extending to the external electrolyte chamber, utilizing capillary action to achieve rapid electrolyte replenishment and eliminate local hot spots. Through the coupling design between the hydrophobic and breathable membrane and the electrode interface, oxygen generated by the oxygen-evolving anode directly penetrates and overflows in the form of gas molecules, effectively suppressing bubble formation and accumulation in traditional electrolysis processes, and significantly reducing the ohmic resistance of the interface and operating energy consumption. This invention features an extremely thin structure, high reaction efficiency, and no bubble interference, making it suitable for precise oxygen concentration control in spaces such as refrigerators and precision storage environments.

A voltage testing and display system comprises a voltage display and a partial discharge detector for connection to an electrical conductor via a voltage divider, wherein the voltage divider consists of a coupling capacitance and a circuit impedance, wherein the circuit impedance is a series connection of a capacitive tuning element and an ohmic resistor or a series connection of a capacitive tuning element with an inductive resistor, wherein both the voltage display and the partial discharge detector receive the measurement voltage dropping across the circuit impedance as their input voltage.

The invention relates to the technical field of electrolytic bath management, and discloses a fault classification method and system for an anion exchange membrane electrolytic bath, and the method comprises the steps: collecting an excitation response signal generated after an AC disturbance signal is applied to a to-be-classified anion exchange membrane electrolytic bath, and the cross concentration of hydrogen in oxygen; the alternating current disturbance signal is set to be formed by compounding a high-frequency sine wave and a low-frequency sine wave; obtaining a first ohmic resistance according to a high-frequency excitation response signal in the excitation response signals; obtaining charge transfer resistance according to a low-frequency excitation response signal in the excitation response signals and the first ohmic resistance; and based on a pre-trained fault diagnosis model and a pre-constructed fault rule base, analyzing the first ohmic resistance, the charge transfer resistance and the cross concentration to obtain a fault classification result. According to the method, the health condition of each specific assembly of the anion exchange membrane electrolytic cell is predicted, the application range is wide, and the fault classification result is more accurate.

The utility model discloses a controllable bidirectional transceiving circuit, which comprises a data pulse transmitting end OUT1, a data pulse receiving end IN1, a master-slave machine control mode switching end IO1, a data pulse transmitting end OUT2, a data pulse receiving end IN2 and a master-slave machine control mode switching end IO2, the data pulse transmitting end OUT1 is sequentially connected with a zero-ohm resistor element R7 and a zero-ohm resistor element R34 and then is connected with a fourth interface of the relay K2, and a third interface of the relay K2 is connected with a diode D3. According to the utility model, logic components are added to control master-slave switching, the relay is controlled through the characteristics of the logic gate so as to determine the receiving and transmitting mode of pulse data, the defects that the host can only transmit and cannot receive and cannot display the detection result are overcome, both parties can check the data of a detection line, and the detection efficiency is improved. And the detected line conditions can be mutually verified at the same time, so that the line can be replaced and overhauled more quickly, and the working efficiency is improved.

Instrumented nut, clamping sleeve, clamping device and method for tightening such a nut. The invention relates to an instrumented metal nut (10b) comprising a tubular body having a polygonal drive surface (14). The nut comprises, on at least one annular portion (34) of the outer surface: an electrically insulating layer (36) applied to the annular portion; a piezoresistive conductive polymer (38) whose ohmic resistance varies according to a stress exerted during tightening of the nut on a threaded fastener, said conductive polymer being applied to the electrically insulating layer; and at least two electrodes (40). Figure for the abstract: Figure 2

Sensor (1) with a temperature measuring bridge (10) comprising a first ohmic resistor (11), a second ohmic resistor (12), a third ohmic resistor (13) and a fourth ohmic resistor (14), wherein the first ohmic resistor (11) and the second ohmic resistor (12) are arranged in series and form a first voltage divider (15), wherein the third ohmic resistor (13) and the fourth ohmic resistor (14) are arranged in series and form a second voltage divider (16), wherein the temperature measuring bridge (10) is configured such that the supply voltage (U D ) of the temperature measuring bridge (10) between the first ohmic resistor (11) and the third ohmic resistor (13) and between the second ohmic resistor (12) and the fourth ohmic resistor (14), and wherein the bridge voltage (U) is to be applied D) of the temperature measuring bridge (10) between the first ohmic resistance (11) and the second ohmic resistance (12) and between the third ohmic resistance (13) and the fourth ohmic resistance (14), wherein the first ohmic resistance (11) and the fourth ohmic resistance (14) have the same ohmic resistance value, the second ohmic resistance (12) and the third ohmic resistance (13) have the same ohmic resistance value, and all four ohmic resistances (11, 12, 13, 14) are arranged centrally with respect to a mechanical stress to be compensated.

This application discloses a method and apparatus for calculating the ohmic resistance of a planar solid oxide fuel cell stack, relating to the field of fuel cell and electrolysis device technology. The method includes: obtaining the geometric structural parameters, material conductivity parameters, and current collector structure parameters of a single cell in the planar solid oxide fuel cell stack; based on the current collector structure parameters, performing an equivalent reconstruction of the current conduction path in the electrodes to establish an equivalent current conduction model including the influence of the current collector path; based on the equivalent current conduction model, calculating the equivalent ohmic resistance of the single cell under operating conditions according to the geometric structural parameters and the material conductivity parameters; and using the equivalent ohmic resistance of the single cell as the ohmic resistance of the planar solid oxide fuel cell stack. This application can accurately calculate the ohmic resistance, improving the accuracy of stack structure optimization and performance analysis.

The invention discloses a method for correcting a potentiodynamic scanning curve and quantifying the deviation degree based on an attachment layer recessive ohmic resistance influence, and belongs to the technical field of conductive component nondestructive testing. Obtaining an experimental potential-current curve of the to-be-tested component through potentiodynamic scanning; constructing a potentiodynamic scanning equation for comprehensively representing the implicit ohmic resistance influence introduced by a cathode reaction, an anode reaction and a component surface attachment layer; fitting the equation with an experimental curve, and optimizing model parameters to enable the equation to be matched with the experimental curve, so as to extract numerical values of all parameters in the electrokinetic potential scanning equation from a fitting result; substituting the parameters back to a potentiodynamic scanning equation and removing the influence of an attachment layer to obtain a corrected curve and accurately calculating the polarization resistance of the component; and comparing the curves before and after correction so as to peel off the influence of the invisible ohmic resistance brought by the attachment layer on the dynamic potential scanning result. According to the invention, the corrosion condition of the conductive material can be rapidly, accurately and nondestructively evaluated.

The invention discloses a method for detecting the remaining capacity of a battery on line, and the method comprises the steps: determining the remaining capacity of the battery at a current sampling moment through employing an ampere-hour integral method when determining that the battery is in a dynamic state; when determining that the battery is in a static state, acquiring an open-circuit voltage value of the battery at the current sampling moment, an ohmic resistance of the battery at the current sampling moment and a temperature of the battery at the current sampling moment; according to the open-circuit voltage value at the current sampling moment, the temperature at the current sampling moment and a first preset corresponding relation, determining a first residual electric quantity of the battery at the current sampling moment; determining a second residual electric quantity of the battery at the current sampling moment according to the ohmic resistance of the battery at the current sampling moment, the temperature of the battery at the current sampling moment and a second preset corresponding relation; and determining the remaining power of the current sampling moment according to the first remaining power of the battery at the current sampling moment and the second remaining power of the battery at the current sampling moment. The remaining capacity of the battery is determined in different modes, and errors in a single mode are reduced.

The resistance converter has inputs for passive resistors. The converter allows the conversion of one standardized passive resistance characteristic curve to another standardized resistance characteristic curve. The output emulates a corresponding ohmic resistance.

The application discloses a low-ESR thin film capacitor and a preparation method thereof. The low-ESR thin film capacitor comprises a shell, a core arranged in the shell, and a lead-out electrode. The core is at least wound by a metalized film. The metalized film comprises a base film and a first metal layer arranged on the surface of the base film. The first metal layer comprises an edge region and a center region. The thickness of the edge region is greater than that of the center region. The base film comprises a plurality of primary microstructures and a plurality of secondary microstructures. The size of the secondary microstructure is smaller than that of the primary microstructure. The primary microstructure comprises a protrusion or a groove. The secondary microstructure comprises a protrusion or a groove. The first end of the lead-out electrode is connected with the core. The edge region with the highest current density has a lower ohmic resistance due to the thicker metal layer, thereby significantly reducing the overall ESR of the whole capacitor. While reducing the ESR, the capacitor can also have a certain self-healing ability.

The invention relates to the technical field of storage batteries, in particular to a storage battery which comprises a shell in which a plurality of groove units isolated from one another are arranged; the battery cover is arranged at the top opening of the shell; the plurality of pole group structures are respectively arranged in the plurality of groove body units; the plate group structure comprises a plurality of positive plates and a plurality of negative plates, a plurality of negative plates; a plurality of partitions; the positive tab of the first end positive plate or the positive tab of the second end positive plate is provided with a first bending structure, and the first bending structure extends towards the middle positive plate; a negative tab of the first end negative plate or a negative tab of the second end negative plate is provided with a second bending structure, and the second bending structure extends towards the middle negative plate; the bent end tab is closer to the middle pole plate, the conduction distance of current from the end pole plate to the busbar is reduced, the ohmic resistance is reduced, and therefore heat is reduced, and the high-rate discharge performance is improved.

The application provides a battery state estimation method, system and medium, relates to the technical field of battery management systems, and establishes a second-order RC equivalent circuit model, adopts RLS online identification of ohmic resistance, polarization resistance and polarization capacitance and other parameters with a forgetting factor, constructs a micro state SRCKF channel and a macro parameter SRCKF channel, carries out real-time correction on a SOC influence factor and a current influence factor based on a filtering performance index, adjusts a process noise and a measurement noise covariance in a self-adaptive adjustment process according to a split-channel logic, and simultaneously introduces cross-channel collaborative self-adaption; SOC and terminal voltage estimation values are output from the state channel, dynamic resistance and maximum available capacity are output from the parameter channel, and SOH is calculated and output. The method improves the estimation accuracy and robustness under low SOC and large current working conditions, has good numerical stability, and is suitable for full-life cycle monitoring of power batteries.

The application provides a fuel cell water management fault diagnosis method and system. The method comprises the following steps: controlling the on-off of the output current of the fuel cell by using DC / DC, periodically recording the voltage change before and after the current interruption, and processing the step data of the voltage response and the relaxation data of the voltage response; calculating the ohmic resistance according to the step data of the voltage response; calculating the diffusion resistance coefficient according to the relaxation data of the voltage response; judging the dry-wet state inside the fuel cell through the ohmic resistance and the diffusion resistance coefficient; and adjusting the operation parameters in real time according to the dry-wet state inside the fuel cell, so that the fuel cell can keep the best working state. The system comprises a data acquisition unit, an ohmic resistance calculation unit, a diffusion resistance coefficient calculation unit, a dry-wet state judgment unit and a central control unit. The application realizes the real-time feedback of the dry-wet state inside the fuel cell by periodically monitoring the change of the ohmic resistance and the diffusion resistance coefficient inside the fuel cell.