74results about How to "Fast current response" patented technology

The invention discloses a method for preparing a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) composite modified electrode. The method comprises the following steps of: uniformly mixing PEDOT:PSS aqueous dispersion liquid and Nafion, which are taken as raw materials, and then directly dispensing a mixture on the surface of a composite modified electrode; and in the conventional three-electrode system, performing secondary electrochemical doping by using hydrophobic ionic liquid, and thus obtaining the PEDOT:PSS composite modified electrode which is high in water resistance and high in conductivity. The PEDOT:PSS composite modified electrode which is prepared by the method fully combines the film-forming property of the PEDOT:PSS aqueous dispersion liquid, the adhesion characteristic, biological compatibility and anti-interference characteristic of the Nafion, high conductivity and hydrophobicity of the ionic liquid and the electrochemical catalysis characteristic of a nanometer material, can be applied to electrochemical biosensors or electrochemical sensors, is directly applicable to electrochemical detection of auxin, roxithromycin, vitamin C, benzenediol isomer, organophosphorus, glucose, hydrogen peroxide and the like, and has the characteristics of good detection effect, short response time, high water resistance, wide linear range, high sensitivity, high anti-interference, high stability and the like.

The invention relates to a photoelectrochemical sensor, and preparation and application thereof. A preparation method for the photoelectrochemical sensor comprises the following steps: S1, pretreating ITO electro-conductive glass; S2, adding TiO2 nanoparticles onto the ITO electro-conductive glass drop by drop to prepare an ITO/TiO2 electrode; S3, soaking the electrode in a carbon quantum dot solution for 10 h so as to obtain an ITO/TiO2/CODs electrode; S4, adding chitosan onto the electrode drop by drop so as to obtain an ITO/TiO2/CODs/CS electrode; S5, adding a glutaraldehyde solution onto the electrode drop by drop; and S6, dropwise adding thrombin aptamer drops, carrying out a reaction at 4 DEG C under a wet condition for 10 to 15 h, continuing adding bovine serum albumin onto the electrode drop by drop after leaching and blow-drying, and carrying out leaching and blow-drying again. The prepared photoelectrochemical sensor can be used for detection of thrombin. According to the invention, the carbon quantum dots with a wide visible light absorption range, good luminosity and high-efficiency electron injection capability are used as a photosensitizer for titanium dioxide, so the obtained composite structure has good response to photoelectric current under visible light. The prepared photoelectrochemical sensor has the advantages of simple operation, low cost, environment friendliness, high sensitivity and good selectivity.

The invention discloses a speed sensorless vector control method for an induction motor, which comprises the followings steps: performing flux linkage control: setting an instruction value of field current and performing closed-loop control of the field current; performing coordinate transformation: transforming the detected stator current value of the induction motor into a field current component and a torque current component of the motor; performing speed control to obtain synchronous angular frequency; performing flux linkage evaluation to obtain the position of a rotor flux linkage; performing torque voltage calculation to obtain the instruction value of the torque voltage; and performing coordinate transformation: transforming the instruction value of exciting voltage and the instruction value of the torque voltage into a three-phase static coordinate, performing corresponding pulse-width modulation, and driving a power inverter unit to generate three-phase alternating voltage to drive the induction motor to operate. According to an experimental result, a speed sensorless induction motor control system has good dynamic performance, and is fast in current response under sudden load increase and decrease conditions, strong in loading capacity in the whole speed regulation range, small in parameter dependence, stable, reliable, and strong in robustness.

The invention discloses a device and a method for reactive power compensation and harmonic suppression of a grid-connected potovoltaic system. The method comprises the following steps of: directly acquiring current on a harmonic source, decomposing the acquired current into harmonic current, fundamental current, reactive current and active current through Fourier transformation, doing a summation on the harmonic current requiring compensation and the reactive current to obtain compensating current, comparing the compensating current with command current, utilizing PWM (pulse width modulation) tracking control method to output PWM waveforms according to the comparison results and driving the PWM waveforms to first control the state of every switching tube in an inversion unit and then control the current output by the inversion unit. Therefore, current on a load can track the command current in a sawtooth wave form, the harmonic current and the reactive current can be offset and the purposes of harmonic suppression and reactive power compensation are achieved. The device and the method can be realized on the basis of the traditional grid-connected potovoltaic system, and the device has a simple structure, carries out detection and control in a real-time manner and has fast responding current.

The invention relates to a non-salient-pole permanent magnet synchronous motor direct characteristic control system and a control method. The control system comprises a position loop control circuit, a rotating speed loop control circuit, a stator current detection module, a sliding mode variable structure observer, a prediction control module, a characteristic control module, a time-delay module, and an inversion module, the stator current detection module is connected with a permanent magnet synchronous motor, an input terminal of the sliding mode variable structure observer is connected with the stator current detection module, the position loop control module, and the time-delay module, an output terminal of the sliding mode variable structure observer is connected with an input terminal of the prediction control module, the input terminal of the prediction control module is connected with the position loop control circuit and the time-delay module, an output terminal of the prediction control module is connected with an input terminal of the characteristic control module, the input terminal of the characteristic control module is connected with the position loop control circuit and the rotating speed loop control circuit, an output terminal of the characteristic control module is connected with the unit time-delay module and an input terminal of the inversion module, and an output terminal of the inversion module is connected with the permanent magnet synchronous motor. Compared with the prior art, the system is advantaged by more compact structure, accurate control, fast current response speed and the like.

The present application discloses a permanent magnet synchronous motor (PMSM) flux weakening control method and a controller. The method comprises selecting a direct-axis current initial value and a quadrature-axis current initial value which are approximate values of the direct-axis current and the quadrature-axis current actually required by the motor; then, enabling the PMSM to operate at the direct-axis current initial value and the quadrature-axis current initial value; finally, adjusting the direct-axis current and the quadrature-axis current of the PMSM in order that the PMSM operates from the direct-axis current initial value to a direct-axis current target value, and from the quadrature-axis current initial value to a quadrature-axis current target value, wherein the direct-axis current target value is the direct-axis current actually required by the motor, and the quadrature-axis current target value is the quadrature-axis current actually required by the motor. It can be seen that the current response speed can be greatly increased by quickly locking an approximate value of the actually required current, operating the PMSM at the approximate value and adjusting the current of the PMSM on this basis.

Copper nanowires are synthesized and are mixed with rGO-TEPA; a mixture is modified onto a glassy carbon electrode; after the drying at room temperature, a mixture of acetylcholinesterase and chitosanglutaraldehyde is modified onto the electrode; the electrode is put into a refrigerator for incubation to a dry state; and an AChE-CS/rGO-TEPA-Cu NWs/GCE (acetylcholinesterase-chitosan-glutaraldehyde/reductive graphene oxide-tetraethylenepentamine-copper nanowires/glassy carbon electrode) biosensor is built. An electrochemical biosensor used for organic phosphorus detection is built by using theinhibition effect of the organic phosphorus on acetylcholinesterase. The advantages of simplicity, convenience, high sensitivity and the like are realized. A novel space is developed for an organic phosphorus detection technology.

The invention provides a modified glassy carbon electrode, which is an L-cysteine modified glassy carbon electrode or a platinum/L-cysteine modified glassy carbon electrode. The preparation method for the L-cysteine modified glassy carbon electrode includes the steps: firstly, treating a glassy carbon electrode into a bare glassy carbon electrode; secondly, drying the bare glassy carbon electrode and inserting the bare glassy carbon electrode into electrolyte solution for cyclic voltammetry scanning to obtain treated glassy carbon electrode; and thirdly, placing the treated glassy carbon electrode into buffer solution containing L-cysteine for electro-polymerization, and obtaining the L-cysteine modified glassy carbon electrode after cleaning and drying the treated glassy carbon electrode. Besides, the platinum/L-cysteine modified glassy carbon electrode is obtained by placing the L-cysteine modified glassy carbon electrode into sulfuric acid solution containing chloroplatinic acid for electro-deposition and after cleaning and drying the L-cysteine modified glassy carbon electrode. The invention further provides application of the modified glassy carbon electrode in the nitrite detection. The modified glassy carbon electrode is capable of promoting electron transfer, current response is enhanced, a modification method is simple and convenient, and the modified glassy carbon electrode is simple in operation, fine in responsiveness and applicable to nitrite detection.

The invention discloses an overspeed electronic load system. The overspeed electronic load system comprises a man-machine interaction interface, a control system, a resistance matching module, a sampling circuit and an output port, wherein the resistance matching module comprises the resistance network and electronic switches, a resistance value is divided by the resistance matching module into different multiple value segments, each resistance value segment internally comprises multiple different resistance values and the electronic switches in parallel and series connection modes to carry out resistance value matching to form the resistance network, an output end of each resistance value segment outputs a resistance value through a relay switch to an output port of an electronic load, the man-machine interaction interface and the control system are connected and realize mutual data transmission, and an output end of the control system is connected with the resistance matching module and is used for controlling resistance matching of the resistance matching module.

The invention relates to a preparation method and an application of a ZnFe2O4 modified electrode material. The method comprises the following steps: synthesizing ZnFe2O4 nanoparticles by a one-step hydrothermal process from bottom to top, and loading the ZnFe2O4 nanoparticles on foamed nickel to obtain the ZnFe2O4/foamed nickel modified electrode material. The ZnFe2O4/foamed nickel modified electrode material is applied to an enzyme-free electrochemical glucose sensor as an electrode. The method is simple and easy to operate; the material can be directly used for rapid electrochemical determination of enzyme-free glucose; compared with similar sensors, the glucose sensor has the following advantages: the detection sensitivity can reach 1160 [mu]A/mMcm<2>, the lowest detection limit reaches0.3 [mu]M, the detection range reaches 10 [mu]M to 100 mM, the current response is high, the stability is good, and the glucose detection efficiency and accuracy can be improved. When the sensor is applied to glucose detection, the sensitivity of glucose detection can be effectively improved, the linear interval of glucose detection is widened, and a relatively low detection limit can be realized.

The invention discloses a dual-motor driving system of a nine-switch inverter and a control method thereof. The system comprises two three-phase permanent magnet synchronous motors, a three-phase nine-switch inverter, a PI controller, a reference current generator, a hysteresis controller, a PWM pulse generating unit, a permanent magnet synchronous motor current detecting sensor, a Hall sensor anda direct current ( DC) power supply, wherein one end of the PI controller is connected with the DC power supply, and the other end is connected with the two three-phase permanent magnet synchronous motors through the reference current generator, the hysteresis controller, the PWM pulse generating unit and the three-phase nine-switch inverter in turn, and the permanent magnet synchronous motor current detecting sensor and the Hall sensor are respectively connected with a position and speed comparator and the reference current generator. The invention enables two permanent magnet synchronous motors to operate synchronously. According to the control topology structure and its control method, the power loss of the nine-switch inverter driven dual-permanent magnet synchronous motor is reducedby declining the number of the power switching tubes.

The invention discloses a method for determining a q-axis current compensation value of a permanent magnet synchronous motor and a pulsation suppression method. The method comprises the following steps: synchronously acquiring a q-axis current feedback signal iq and a rotor position signal theta m, determining a position interval of a rotor based on the theta m, accumulating the interval times by1 and performing synchronous averaging on the iq, and repeatedly acquiring until the accumulated value of the interval times is greater than a threshold value and all the intervals are not overlappedto form a circle of the rotor; performing fast Fourier transform on the synchronous average value corresponding to each interval arranged in sequence to obtain frequency domain characteristic information, determining the amplitude and the phase angle of a to-be-compensated spatial frequency component from the frequency characteristic information, and constructing a q-axis current compensation function; and obtaining a q-axis current compensation value based on the position of the actual compensation moment of the motor rotor and the current compensation function. Time domain information is converted into a space domain, time lag is avoided, the whole process does not affect the dynamic performance of the system, extra devices are not needed, structures and parameters of all control links do not need to be adjusted, and operation is easy.

The invention discloses a permanent magnet synchronous motor wide-range speed regulation control method, device and equipment and a medium. The method comprises: acquiring d-axis and q-axis current reference value query tables of a permanent magnet synchronous motor; selecting d-axis and q-axis current reference value calculation modes; calculating a fitting data point element subscript; obtaininga fitting data value; performing data fitting to obtain d-axis and q-axis current reference values; obtaining a permanent magnet synchronous motor IO parameter matrix estimation law, a voltage reference difference estimation law and a voltage dynamic amplitude limiting value estimation law; acquiring an IO parameter matrix estimated value of the current control period; obtaining d-axis and q-axisvoltage reference difference values of the current control period; obtaining d-axis and q-axis dynamic voltage amplitude limiting values of the current control period; calculating d-axis and q-axis voltage reference values of the current control period; carrying out dynamic amplitude limiting on the d-axis voltage reference value and the q-axis voltage reference value; controlling permanent magnet synchronous machine. The method has the advantages of high robustness, continuous current working points, high current response speed, high tracking precision, small data storage capacity and the like.

The invention discloses a method for loading the surface of a TiO2 anode with Co3O4, and relates to the method for loading the surface of the anode with Co3O4. The invention aims to solve the problems that an anode used in a conventional water decomposition device is a noble metal catalyst, the method is complex, the cost is high and the anode cannot be generally applied. The method comprises the steps: 1, preparing a TiO2 slurry; 2, preparing an anode; 3, coating; 4, preparing FTO conductive glass loaded with a TiO2 blank piece; 5, preparing a TiO2 anode; 6, preparing a photosensitizer; 7, preparing a cleaned TiO2 anode having the surface loaded with the photosensitizer; 8, preparing Co3O4 nanoparticles; 9, preparing a Co3O4 dispersion liquid; 10, preparing a Co3O4 catalyst-containing dye-sensitized TiO2 photoanode; 11, synthesizing a biomimetic redox couple; and 12, impregnating, and thus obtaining the TiO2 anode having the surface loaded with Co3O4. The method for loading the surface of the TiO2 anode with Co3O4 can be obtained.

The invention relates to a self-energized nucleic acid aptamer sensor and a preparation method and an application thereof. The sensor comprises a positive electrode and a negative electrode, the positive electrode is used for a spontaneous catalytic oxidation reaction of GCE/CNTs-COOH/GDH, and the negative electrode is Au/Apt; the preparation method of the sensor comprises the following steps: CNTs pretreatment, preparation of GCE/CNTs-COOH/GDH, and preparation of Au/Apt; and the sensor is used for detecting atrazine in liquid. Compared with the prior art, a self-energized sensing analysis method with simple operation and rapid detection as well as a nucleic acid aptamer technology having specific recognition effect on ATZ are combined, the invention provides a method for construction of the self-energized nucleic acid aptamer sensor based on a bio-enzyme fuel cell as well as high-sensitivity high-selectivity analysis detection method on pesticide atrazine in a water body, the detection sensitivity can achieve 7.5*10<-9> mol/L, and the sensor has good reappearance, the sensor has excellent selectivity identification in a hundredfold-concentration hinterferent-existed system, and the problems of low sensitivity, long analysis time consuming and complex operation in the current ATZ detection technology can be solved.

The invention provides a water splitting device, relates to water splitting equipment, and aims to solve the problems that an existing water splitting device is high in cost, and the synergy effect of a catalyst in a used anode and a photosensitizer is poor. The water splitting device consists of a Co3O4 modified photo-anode, a cathode, a first wire, a second wire, a power supply and a water tank containing water, wherein the Co3O4 modified photo-anode and the cathode are arranged in the water tank containing the water; the Co3O4 modified photo-anode is connected with a positive pole of the power supply through the first wire and serves as an anode of the water splitting device; and the cathode is connected with a negative pole of the power supply through the second wire, and serves as a cathode of the water splitting device. The water oxidation efficiency of the water splitting device is 3%-5%. Compared with an existing water splitting device, the water splitting device has lower cost reduced by 99.6%-99.8%. By the invention, the water splitting device can be obtained.

The invention relates to a preparation method of an ascorbic acid oxidase electrochemical biosensing composite modified electrode. The preparation method comprises the steps of: preparing an electrolyte solution from 3,4-ethylenedioxy thiophene, sodium lauroylsarcosine, carbon nanotubes and 1-ethyl-3-methylimidazolium ethyl sulfate, and carrying out 1.1V constant-potential polymerization in a three-electrode system for 60 seconds to prepare the conducting poly(3,4-ethylenedioxy thiophene) nano film composite modified electrode by one-step reaction; and then drip-coating ascorbic acid oxidase buffer on the surface of the composite modified electrode, and finally covering the enzyme layer with a mixed liquid of carbon nanotubes, Nafion and ionic liquid. The constructed composite modified electrode has the advantages of good biological electric catalysis activity to vitamin C, wide linear range, low detection potential, rapid current response, significant sensitivity, high repeatability and stability, good selectivity, high immobilized enzyme activity and strong affinity; and the preparation method has the characteristics of low cost, simple process, and simplicity and easiness in operation and the like.

The invention relates to a novel multilayer tunneling junction and a double-junction laminated battery thereof. The novel multilayer tunneling junction comprises a crystalline silicon substrate, a first ultra-thin dielectric layer, a first heavily doped silicon film, a second ultra-thin dielectric layer and a second heavily doped silicon film, a second heavily-doped silicon film, a second ultrathin dielectric layer, a first heavily-doped silicon film, a first ultrathin dielectric layer and a crystalline silicon substrate are sequentially arranged in the novel multilayer tunnel junction from top to bottom. The crystalline silicon substrate is n-type crystalline silicon or p-type crystalline silicon. The novel multilayer tunneling junction has the beneficial effect that the structure based on the silicon substrate-dielectric layer-first layer silicon thin film is a crystalline silicon cell technology named as passivation tunneling. The technology has a good silicon wafer surface passivation effect and a good carrier collection effect, full-surface carrier collection can be realized by adopting the passivation contact structure, and a metal electrode is not needed, so that the carrierrecombination rate of the whole silicon wafer surface is very low.

The invention discloses a DC motor parallel control system and a current following control method, and the method comprises the steps: obtaining a reference initial current through five PI regulatorsaccording to a difference between a given reference rotating speed and an actual rotating speed; calculating a required reference current value from the reference initial current through a reference current reconstruction calculation module; obtaining a calculated current value from the current value the output end of a six-phase voltage source type inverter passes through a current reconstructioncalculation module; providing the difference value between the calculated current value and the reference current value for a hysteresis comparator to generate square wave signals with equal amplitude and unequal width; converting the square wave signals, by a PWM module, into a switching signal for driving an IGBT; transmitting a PWM signal to the six-phase voltage source type inverter module, controlling the five direct current motors to work normally by the six-phase voltage source type inverter module, and realizing four-quadrant operation of the motors. The invention provides a novel motor control method by adopting a reference current reconstruction technology, a current reconstruction technology and a hysteresis comparison technology.

The invention discloses an insulated conductor voltage testing meter, which comprises two voltage measurement microneedle devices, a test lead wire and a voltage measuring meter. Each voltage measurement microneedle device comprises a protecting cylinder chamber, a pushing device and a micro probe; each pushing device is sleeved inside each protecting cylinder chamber; each pushing device is fixedly connected with each micro probe; each micro probe makes front-and-back piston-type motion in each protecting cylinder chamber along with each pushing device, and is the micro probe made of high-strength copper alloy; the diameter of each micro probe is 100 nanometers; one end of the test lead wire is connected with the micro probes through needle beds. According to the insulated conductor voltage testing meter provided by the invention, the voltage measurement micro probes made of the high-strength copper alloy are completely used for measuring a voltage numerical value directly on an insulated conductor, a measurement process is safe and efficiency, and the measurement result accuracy and the measurement sensitivity are high.

The coulomb island commutating single molecule diode and manufacturing method the feature is: coats silicon dioxide substrate with a poly(methyl methacrylate), etches the slot on the surface with electron beam, evaporates metal to form the metal nano meter ling in the slot, adds the voltage on both end of the metal nano meter line to make it broken and form two metal nano meter electrode; dips the metal nano meter electrode in alkyl mercaptan and ethanol solution to form mercaptan film on the surface of electrode, then drops the solution containing CJ,N,C,IN or C59B on the nano meter electrode; adds DC bias voltage on the both end of electrode short-time, the organic molecule absorbed in one of the electrode mercaptan film and two electrode constitutes the coulomb island single molecule diode that has commutating effect.

The invention discloses a global online heuristic type based dynamic planning permanent magnet synchronous motor vector control method. A current ring adopts an improved approaching rate sliding modevariable structure controller, reduces current buffeting phenomenon and inhibits torque pulsation of the permanent magnet synchronous motor; a speed ring applies a mononeuron global online heuristic type based dynamic programming algorithm to evaluate the parameter change of the permanent magnet synchronous motor, and self-adaptively adjusts a discount factor K; through sampling a motor encoder and using the zero difference of a target rotate speed and an actual rotate speed as an optimized target, a study signal is designed and intensified; through generating an internal intensified study signal in a target network, the reference amount of q axis current can be adjusted through continuously online study, the vector change of the permanent magnet synchronous motor is compensated, thereby enhancing the speed anti-interference ability of the permanent magnet synchronous motor. The method presented by the invention has very strong pertinence and practicability to the permanent magnet synchronous motor vector control system.

The invention provides a preparation method for a polyaniline-polyphenol oxidase sensor, relates to the technical field of biosensors, and directly prepares the polyaniline-polyphenol oxidase sensor by direct electrochemical polymerization. The method comprises a step of immobilizing polyphenol oxidase in aniline solution containing ionic liquid and a surfactant to form the polyaniline-polyphenol oxidase sensor. The method mixes the enzyme, a monomer and supporting electrolyte solution by a 'one-step method'' and realizes the immobilization of the enzyme while electrolyzing on an electrode to form a conducting high polymer membrane. The method of the invention has the advantages of high bio-compatibility, proper pore structure and the like, and can realize the effective immobilization of the polyphenol oxidase. The polyaniline-polyphenol oxidase sensor prepared by the method has the advantages of high electrochemical activity even at a high pH, quick response to a substrate, high sensitivity, relatively wide linear range, and high repeatability and stability. The sensor can monitor phenolic compounds.

The invention provides a preparation method of an electrochemical sensor based on an MWCNTs/ZIF-8 (at) Ag composite material, and is applied to detection of a phenolic antioxidant chlorogenic acid. A carboxylated carbon nanotube and a ZIF-8 (at) Ag composite material are respectively prepared, the carboxylated carbon nanotube is fixed on a glassy carbon electrode by chitosan to serve as a substrate material, ZIF-8 (at) Ag is superposed and fixed on the substrate material to obtain a modified working electrode, and the electrochemical sensor prepared according to the method can be accurately, simply, conveniently and quickly used for sensitive detection of chlorogenic acid.

The invention discloses a preparation method of a non-enzyme glucose electrochemical sensor. The preparation method comprises the following steps: (1) pretreating a substrate; (2) preparing a mixed metal ion solution and a sulfide solution; (3) performing in-situ growth on the substrate to prepare a copper-cobalt-nickel sulfide modification layer; (4) drying the prepared copper-cobalt-nickel sulfide electrode; and (5) using the copper-cobalt-nickel composite sulfide electrode prepared in the step (4) as a working electrode, forming a three-electrode system with a counter electrode and a reference electrode, and connecting the three-electrode system with an electrochemical workstation to form an electrochemical sensor, thereby obtaining the copper-cobalt-nickel composite sulfide enzyme-free glucose electrochemical sensor. The novel non-enzyme sensor is constructed by using the copper-cobalt-nickel composite sulfide, is applied to high-sensitivity detection of the glucose content in human serum, and shows a relatively wide linear range, an extremely low detection limit and good anti-interference capability and stability.

The invention discloses a preparation method for an electrode modified material of a silver indium disulphide/a reduced graphene oxide and an application thereof for detecting the ciprofloxacin. The preparation method comprises the following steps of: mixing the GO (graphene oxide) dispersion and the AgInS2 solution thoroughly and uniformly; transferring the GO dispersion liquid into a reaction kettle for the hydrothermal reaction to compound; obtaining the product AgInS2/rGO by filtering, washing, and freeze-drying after the reaction is completed; using a glassy carbon electrode modified by aprepared AgInS2/rGO nanocomposite as a working electrode, using an Ag/AgCl electrode as a reference electrode, using a platinum electrode as a counter electrode; using a 1M H2SO solution as a supporting electrolyte solution; and utilizing a differential pulse voltammetry (DPV), so that the invention can detect solutions containing different concentrations of ciprofloxacin. According to the preparation method for the electrode modified material of the silver indium disulphide/the reduced graphene oxide, the method responds quickly to the current of ciprofloxacin, and the method has a high sensitivity, a low detection limit, a strong anti-interference performance, and a high practicability.