38results about How to "Play the role of filtering" patented technology

The invention discloses a single-phase non-isolated photovoltaic grid-connected inverter and a control method. The photovoltaic grid-connected inverter mainly comprises a half-bridge circuit, a full-bridge circuit and a control circuit, wherein the control circuit controls the half-bridge circuit and the full-bridge circuit, so that the half-bridge circuit can be modulated in a high-frequency sinusoidal pulse width modulation (SPWM) mode to output half-sinusoidal current, and the full-bridge circuit can commutate in an industrial-frequency mode to commutate the half-sinusoidal current output by the half-bridge circuit and output sinusoidal current required for grid connection. The photovoltaic grid-connected inverter can ensure that the problem of common-mode current in the non-isolated grid-connected inverter circuit is effectively solved, the distortion of the current at the zero crossing point is reduced and the high-frequency switching loss in the circuit is low at any time.

The invention discloses a method for predicting a zero crossing point of an ultrasonic signal based on multi-threshold comparison. The problem of poor anti-jamming capability is existent in the traditional zero crossing detection method of performing voltage comparison on a signal and a zero potential and directly determining the zero crossing point of the signal in a measuring way. The method comprises the steps of by adopting a measurement and computation combined method, acquiring sample point parameters in a measuring way by multi-thread comparison, carrying out ultrasonic waveform curve fitting, and computing the zero crossing point of the ultrasonic received signal by a curvilinear equation obtained by fitting. According to the method, the problem of poor anti-jamming capability in the traditional zero crossing detection method is effectively solved, and the precision and reliability of the zero crossing detection of the ultrasonic signal are improved. The method is suitable for various ultrasonic detection fields, in particular for gas ultrasonic flow meters with low signal to noise ratios of received wave signals; and the detection precision and the anti-jamming capability can be greatly improved.

The invention discloses a magnetic-integration three-phase filter transformer. The magnetic-integration three-phase filter transformer comprises a transformer core window, wherein a leakage flux branch plate is arranged in the transformer core window; gaps are respectively reserved between the leakage flux branch plate and an upper yoke and between the leakage flux branch plate and a lower yoke; a high-voltage winding coil and a low-voltage winding coil are respectively wound between core columns and the leakage flux branch plate; a low-voltage winding is positioned on the inside, and a high-voltage winding is positioned on the outside; and a filter capacitor is connected with the low-voltage winding coil in parallel. A filter inductor is integrated with the transformer, so that the size of the integrated body of the inductor and the transformer is small, the inductor and the transformer are light, and materials are saved. The columns of three-phase cores are in magnetic flux with the filter inductor and the transformer simultaneously. When the magnetic flux is highest, common magnetic flux and leakage magnetic flux are in different phases, and magnetic cores can be saved to a certain degree. Four single-phase windings of the transformer also have a filtering function, and substitute an independent filter inductor. Moreover, the number of used copper wires of the transformer and the inductor which are integrated is smaller than the number of used copper wires of the transformer and the inductor which are independent from each other.

The invention provides a system wave aberration detection method capable of calibrating system errors. The system wave aberration of a projection objective to be detected is subtracted from the system errors of a shear interference detection system to obtain the actual wave aberration of the projection objective to be detected, the influence of the system errors is eliminated, and measuring accuracy is improved. A filtering function can be achieved by a small hole space filter, aberration caused by a lighting system and a first convergence lens can be eliminated, and detection accuracy of the system wave aberration is improved. Only + / - level diffraction light can pass a window in the space filter, zero and higher level diffraction light is intercepted by the space filter, so that noise is reduced, and measuring precision is improved.

The invention discloses an over-voltage protection method for the DC bus voltage of a wind power current transformer and a circuit adopting the same. The method comprises the steps as follows: a square wave signal with a certain amplitude value, a certain frequency and a certain positive duty cycle is generated correspondingly according to the actually needed over-voltage protection value of a DC bus voltage by adopting the software table checking method of a DSP (Digital Signal Processor) chip; the square wave signal is compared with a normal value signal to output a square wave signal with a certain amplitude value, the identical frequency and the identical positive duty cycle, and the circuit completing the first time comparison output is a primary comparison circuit; the square wave signal receives special circuit treatment to be changed into a normal value signal reaching the pre-determinate over-voltage protection value of the DC bus voltage, the normal value signal and the conversion value of the actually detected DC bus voltage are compared to send an output signal to the DSP chip, and the circuit completing the second time comparison output is a secondary comparison circuit; and the DSP chip decides whether overvoltage exits in the DC bus voltage of the wind power current transformer.

The invention relates to an oil-paper insulation Debye circuit parameter identification method based on an adaptive sampling interval Prony algorithm. The method is characterized by based on the physical characteristics of the depolarization current exponential function superposition under a Debye equivalent model, improving a traditional Prony algorithm, realizing the adaptive selection of the sampling intervals according to a time constant range which can be accurately solved at a certain sampling interval, and carrying out the Prony fitting on the relaxation sub-spectral lines of the corresponding time constants by utilizing the adaptive sampling intervals; and after the sub-spectral line parameters are obtained, substituting the sub-spectral line parameters into a Debye equivalent circuit parameter identification formula to realize the identification of the equivalent circuit parameters. According to the method, the subjectivity of the manual point selection and sampling interval selection is avoided, a filtering effect on the actually measured depolarization current with the noise interference is achieved, and the identification of the Debye equivalent circuit parameters of anoilpaper transformer is accurately and uniquely achieved.

The invention discloses a wireless and magnetic field induction technology combined high precision positioning technology and a corresponding sensor device. The specific technology includes that: (1) a matrix distribution analog Hall voltage detection way is adopted; (2) a wireless radio frequency technology is employed to identify landmark information, and positioning and identification are combined into one; (3) the indoor and outdoor general positioning sensor is not disturbed by rain, snow, thunder, electricity and other environmental factors; and (4) the positioning sensor and method support multi-interface communication and multi-module combination. Compared with current traditional magnetic induction positioning technology, the positioning sensor and method provided by the invention have the advantages of high positioning precision, good stability, good scalability, low cost, concise connection line, and strong anti-interference ability, etc., and are suitable for high precision mobile robot magnetic stripe navigation under various environments.

The purpose is to provide an accumulator type electronic control fuel injection system with the variable supercharge ratio. The system comprises a common rail pipe, a high-pressure oil pipe, a high-pressure oil pump, a filter, an oil tank, an oil return pipe and an oil atomizer. A second-level electromagnetic valve structure is adopted, a pressurizing area of a three-level piston is controlled, different supercharge ratios can be effectively achieved, and the oil injection law can be more flexible; the motion process of a needle valve is firstly driven by a guide type electromagnetic valve, the responding speed of the needle valve is high, the control freedom degree is large, the oil injection law is flexible and controllable, the dynamic property of a diesel engine and the economical efficiency of fuel are effectively improved, and the diesel engine can meet more strict emission regulations; a pressurizing control valve and an oil injecting control valve are soaked in low-pressure oil, which has a cooling effect on the electromagnetic valve, and safe and reliable work is ensured; a hole plate structure is arranged in a pressure storage cavity, fluctuation of pressure of fuel in the oil atomizer is reduced, fluctuation of circular fuel-injection quantity is reduced, and the multi-time injecting process of a high-pressure common rail fuel system is further controlled more accurately.

The invention relates to a mixer based on the current multiplexing technology. The mixer comprises a trans-conductance stage circuit, a switching stage circuit and a load stage circuit that are connected successively. The trans-conductance stage circuit employs a current multiplexing structure and a source degeneration inductance structure. The trans-conductance stage circuit is used for realizingaccess of a radio-frequency voltage signal, converting the radio-frequency voltage signal into a radio-frequency current signal, and reusing the radio-frequency current signal repeatedly. The switching stage circuit is used for realizing access of a local oscillator signal and a radio-frequency current signal, controlling conduction of a plurality of arranged switching tubes alternately based onthe local oscillator signal, carrying out switching modulation on the radio-frequency current signal by alternate conduction of the plurality of arranged switching tubes, and generating an intermediate-frequency current signal and transmitting the signal to the load stage circuit. The load stage circuit is used for converting the intermediate-frequency current signal into a voltage signal and outputting the converted signal. Compared with the prior art, the mixer has advantages of simple structure, high conversion gain, high linearity, low noise, low power consumption, and good port isolationperformance.

The present invention discloses a fuse tube with the function of wave filtration, and the fuse tube includes a metal wire and a tube; wherein, the metal wire is arranged in the tube which is filled with granular electric wave absorption materials. The granular size of the electric wave absorption materials stands at 50 items to 300 items. The advantage is that the tube is filled with granular electric wave absorption materials that can well absorb or isolate the interference of miscellaneous waves, at the same time, reduce and restrain the influences of the miscellaneous wave interference produced in the working of the machine on other equipments via a power supply loop. By entering into the front end of the machine power supply, the function of wave filtration can be effectively brought into full play, thus letting the machine have better anti-interference capability in the increasingly serious ambience of electromagnetic interference and have more stable working performance and the state of the machine.

The invention, which belongs to the field of the electronic technology of the pyroelectric detector, discloses a pyroelectric detector comprising an optical system, an infrared sensor unit, a signal processing circuit, and an output control device. The pyroelectric detector is characterized in that the signal processing circuit consists of an operational amplifier, a capacitor C1, a capacitor C2, a resistor R1, a resistor R2, and a resistor R3; after the capacitor C1 and the resistor R2 that are inputted into an original signal terminal are connected in series, the serial unit is connected with an in-phase input terminal (3) of the operational amplifier; one end of the resistor R3 is grounded and the other end of the resistor R3 is connected with an inverting output terminal (2) of the operational amplifier; and the resistor R1 and the capacitor C2 are connected in parallel between the in-phase input terminal (3) of the operational amplifier and an output terminal (1). The power supply way of the operational amplifier is a voltage power supply way; and Vo is a signal processing output terminal. The pyroelectric detector has the following advantages: the performances are stable; reliability is high; detection signals with high responses and low noises can be detected and outputted without any error in various working environments; and large-scale industrial production can be realized.

The invention relates to a Ka-band MMIC (monolithic microwave integrated circuit) low-noise amplifier and mainly solves the technical problem that the prior art has high noise coefficient, poor in-band gain flatness and poor linearity. The Ka-band MMIC low-noise amplifier comprises a two-stage amplifier, a gamma / 4 transmission wire structure and a three-stage matching network, the two-stage amplifier comprises a primary field-effect transistor amplifier, a primary gate bias network, a primary drain bias network, a primary source resistor ad primary source capacitor parallel network, a secondary amplifier, a secondary gate bias network, a secondary drain bias network, and a secondary source resistor and capacitor parallel network, the gamma / 4 transmission wire structure comprises a first transmission wire mesh connected with the primary gate bias network and a second transmission wire mesh connected with the primary drain bias network; by using the above technical scheme, the problem iswell solved; the Ka-band MMIC low-noise amplifier is applicable to the field of Ka-band communications.

The invention relates to the technical field of CAN (Controller Area Network) bus for new energy vehicles and in particular relates to a CAN analysis circuit and method for the new energy vehicles. The CAN analysis circuit comprises a CAN transceiver and a common mode inductor; a seventh end of the CAN transceiver is connected with a first input end of the common mode inductor; a sixth end of theCAN transceiver is connected with a second input end of the common mode inductor; a first output end and a second output end of the common mode inductor are connected with the CAN bus respectively. According to the CAN analysis circuit for the new energy vehicles, disclosed by the invention, the CAN transceiver and the common mode inductor are arranged; a common mode electromagnetic interference signal is filtered by utilizing the common mode inductor; meanwhile, an EMI (Electro Magnetic Interference) filtering effect is realized, and electromagnetic wave generated by a high-speed signal lineare prevented from being radiated and transmitted to the outer side; the anti-interference capability of the CAN analysis circuit is improved and the reliability of a signal in high-speed transmissionis ensured.

The invention discloses a paper fullness detection circuit and a paper fullness detection method for distinguishing infrared rays. The circuit comprises a power input end, an infrared transmitting circuit, an infrared receiving circuit and a signal output end, the power supply input end supplies power to the infrared transmitting circuit and the infrared receiving circuit; the infrared transmitting circuit emits infrared light; the infrared receiving circuit receives infrared light; the signal output end is electrically connected with the output end of the infrared receiving circuit; the circuit also comprises a single-chip microcomputer circuit, a first filter circuit and a second filter circuit; and the single-chip microcomputer circuit is electrically connected with the infrared transmitting circuit and controls the infrared transmitting circuit to emit pulse infrared light. According to the circuit, pulse infrared light signals are adopted to replace direct-current infrared light to serve as detection signals, the pulse infrared light signals can be effectively distinguished from direct-current signals of sunlight, interference of the sunlight is avoided, an anti-interference performance is high, and the height of paper scraps in a paper shredding barrel can be effectively judged.

The invention relates to the high-voltage power supply field, particularly to a high-voltage electricity saving system. A high-voltage input terminal is connected in series with a three-dimensional rolling-iron-core auto transformer; an output terminal of the three-dimensional rolling-iron-core auto transformer is a multi-tap voltage regulator exciting winding provided with a plurality of gears; each gear output is connected with a switch; and each switch is connected with a control chip. With the mutual balancing effect of three phases of the three-dimensional rolling iron core in terms of magnetic potentials, voltages transmitted to electrical equipment can be balanced and stabilized, thereby achieving an objective of power saving. Meanwhile, different gears are selected and thus different voltages are outputted, so that the electrical appliance can work with a minimum proper voltage and thus the energy is saved effectively. Moreover, because of series connection of the three-dimensional rolling-iron-core auto transformer, the stability and filtering of the system are enhanced and the power factor of the system is improved.

The invention provides a transverse control method for a pilotless automobile; the method comprises the steps: a vehicle posture collection module collects the state and positioning information of a vehicle, an error calculation module calculates a trajectory tracking error, an LQR controller which does not consider the influence of road curvature obtains a feedback control signal according to the tracking error, and the feedback control signal is sent to a control module; the feedforward controller considering the influence of the road curvature obtains a feedforward control signal according to the tracking error of the error calculation module, initializes Q and R matrix parameters of the LQR controller and PID controller parameters, and uses an adaptive seagull algorithm to find the optimal parameters of the Q and R matrixes and the PID controller so as to obtain a final output signal of the LQR controller; and a front wheel steering command signal is obtained by the sum of a final output signal of the LQR controller and an output signal of the PID embedded feedforward controller. According to the method, the optimal solution of the Q and R matrixes in the feasible region can be quickly found, and the control effect of the controller is fully exerted to realize the transverse control of the pilotless automobile.

The invention discloses a medical big data basic information collection and analysis system, which comprises a first processor, and the output end of the first processor is bidirectionally and electrically connected with a database, an information analysis module and a data transmission module. Through the arrangement of the first processor, the database, the information analysis module, the data transmission module, the data display module, the control terminal, the information collection module, the weight measurement module, the height measurement module, the information input module and the online monitoring module, the problem that current medical big data cannot be well applied to the life of people is solved; the medical big data basic information collection and analysis system can monitor the daily physical state of people, can collect the symptoms of various diseases and the information of patients, analyzes and compares the symptoms and the information, improves the diagnosis accuracy, can remind people in time when abnormal conditions occur, and improves the diagnosis efficiency. And alarm and rescue can be carried out in time.

The invention relates to a loudspeaker and an earphone with the loudspeaker. The loudspeaker comprises a diaphragm, a first polar plate and a second polar plate, wherein the first polar plate and the second polar plate are located on two sides of the diaphragm and are of mirror symmetry along the diaphragm, electrode layers are formed on the inner surfaces, facing the diaphragm, of the both, the electrode layer of the first polar plate is composed of at least two sub electrodes isolated from each other, and the sub electrodes comprise a first sub electrode connected with a conducting wire and are connected in series via resistors from the first sub electrode; and the aperture ratios of the areas of the sub electrodes on the first polar plate are sequentially reduced from big to small from the first sub electrode in the series direction. The loudspeaker has the advantages: the effect of a point acoustic source is simulated on the premise that loud and loose sound is guaranteed, so that the positioning is more accurate, meanwhile, the capacitance of the loudspeaker is also reduced, the load of an amplifier is reduced, and the loudspeaker is driven more easily. Meanwhile, compared with a conventional electrostatic loudspeaker, the loudspeaker is low in punching rate, improves the strength and uniformity of an electrostatic field and has low sound transmission loss.

The utility model discloses a processing circuit used for improving the performance of the audio equipment, and the processing equipment thereof. The processing equipment comprises a casing body, the input terminal interface of an audio host machine is arranged at one side of the casing body, the input terminal interface of a power supply is arranged at the other side of the casing body, a protective tube with filtering function is connected on the anode power wire of the input terminal of the audio host machine in series, and a capacitor is bridged between the anode power wire of the input terminal and the cathode power wire of the input terminal of the audio host machine. The processing equipment has the advantages that all sorts of harmful resonance in the circuit can be effectively restrained through the capacitor, and the capacitor plays the role of filtering; the protective tube with the filtering function can effectively restrain all sorts of harmful resonance in the circuit, and plays the role of filtering, reduces the impedance caused by vibration, and improves the degree of purity and the stability of the power supply, the higher harmonics components harmful to the signals are eliminated through the optimization of the quality of the power supply, and the powerful output capability is provided for the machine through the high-quality abundant electric current.

The invention discloses a wireless and magnetic field induction technology combined high precision positioning technology and a corresponding sensor device. The specific technology includes that: (1) a matrix distribution analog Hall voltage detection way is adopted; (2) a wireless radio frequency technology is employed to identify landmark information, and positioning and identification are combined into one; (3) the indoor and outdoor general positioning sensor is not disturbed by rain, snow, thunder, electricity and other environmental factors; and (4) the positioning sensor and method support multi-interface communication and multi-module combination. Compared with current traditional magnetic induction positioning technology, the positioning sensor and method provided by the invention have the advantages of high positioning precision, good stability, good scalability, low cost, concise connection line, and strong anti-interference ability, etc., and are suitable for high precision mobile robot magnetic stripe navigation under various environments.

The invention relates to a CDMA-based remote data transmission method. A main controller sends a data request command to a CDMA module; after receiving the data request command sent by the main controller, the CDMA module sends data information to a CDMA interface and stores the data information in an internal data buffer area of the main controller; after the data information is stored in the internal data buffer area of the main controller, AT instruction decoding is carried out, and the data information is stored in a static memory through a memory module. By taking a policy of alternately receiving the data information through two buffer areas, the delay and the lagging of data transmission and data processing are greatly retarded, the aim of parallel processing is achieved, and the performance of the whole remote transmission is improved. In order to avoid the interference on power supplying of the CDMA module caused by high-frequency interference and transient peak values of the surrounding environment, an LC low-frequency oscillating circuit is added to the output end of a voltage stabilizing module, and the filtering effect is achieved, so that the impact on a power supply system of a module power supply can be avoided to a great extent.

The embodiment of the invention provides a target detection method and system based on a feedback mechanism. The method comprises: obtaining a to-be-detected target; inputting the to-be-detected target into an improved IFF target detector to obtain a target detection result, wherein the improved IFF target detector is obtained by adding an IFF module based on a target detector. According to the embodiment of the invention, the IFF feedback module is additionally arranged in the existing target detector, the last prediction result is used as reference information to be fed back to the feature map, the filtering effect can be achieved, the activated area of the feature map can be more concentrated in the target area, and the coupling relation between the category information and the positioninformation can be captured by a network through fusion.

The present invention discloses a fuse tube with the function of wave filtration, and the fuse tube includes a metal wire and a tube; wherein, the metal wire is arranged in the tube which is filled with granular electric wave absorption materials. The granular size of the electric wave absorption materials stands at 50 items to 300 items. The advantage is that the tube is filled with granular electric wave absorption materials that can well absorb or isolate the interference of miscellaneous waves, at the same time, reduce and restrain the influences of the miscellaneous wave interference produced in the working of the machine on other equipments via a power supply loop. By entering into the front end of the machine power supply, the function of wave filtration can be effectively broughtinto full play, thus letting the machine have better anti-interference capability in the increasingly serious ambience of electromagnetic interference and have more stable working performance and thestate of the machine.

The invention discloses a magnetic-integration three-phase filter transformer. The magnetic-integration three-phase filter transformer comprises a transformer core window, wherein a leakage flux branch plate is arranged in the transformer core window; gaps are respectively reserved between the leakage flux branch plate and an upper yoke and between the leakage flux branch plate and a lower yoke; a high-voltage winding coil and a low-voltage winding coil are respectively wound between core columns and the leakage flux branch plate; a low-voltage winding is positioned on the inside, and a high-voltage winding is positioned on the outside; and a filter capacitor is connected with the low-voltage winding coil in parallel. A filter inductor is integrated with the transformer, so that the size of the integrated body of the inductor and the transformer is small, the inductor and the transformer are light, and materials are saved. The columns of three-phase cores are in magnetic flux with the filter inductor and the transformer simultaneously. When the magnetic flux is highest, common magnetic flux and leakage magnetic flux are in different phases, and magnetic cores can be saved to a certain degree. Four single-phase windings of the transformer also have a filtering function, and substitute an independent filter inductor. Moreover, the number of used copper wires of the transformer and the inductor which are integrated is smaller than the number of used copper wires of the transformer and the inductor which are independent from each other.

The invention relates to a mobile outdoor high-voltage active filtering apparatus. The mobile outdoor high-voltage active filtering apparatus comprises a body; a main casing installed on the body; a power supply module installed on the body; and a high-voltage active power filter which is installed in the main casing and is connected with the power supply module. Compared to the prior art, the apparatus has the advantages of effectively solving the problem of system harmonic waves of a remote region, being good in safety and wide in application scope, and the like.

The invention discloses a three-core power line disconnection protector. A front-mounted part and a rear-mounted part are connected into one body through a three-core power line; when a key switch ofthe front-mounted part of a power line protector is pressed, a power supply is supplied to the tail end of the three-core power line from a first cable and a third cable of the three-core power line,is fed back through diodes D3 and D4 of the rear-mounted part and a second cable of the three-core power line, is supplied to a relay JK1 of the front-mounted part, and forms a loop with diodes D1 andD2 of the front-mounted part, the relay JK1 works, and a normally open contact JK1 remains closed; and if any cable of the three-core power line is disconnected, the relay JK1 is powered off, and thenormally open contact of the relay is disconnected and no longer supplies the power supply to back-end household appliances. Therefore, the fault caused when wires in the three-core power line are disconnected and pull electric arcs can be effectively prevented, the problems that the back-end household appliances are damaged, or, surrounding inflammable materials are ignited to cause a fire can be further avoided, and the use safety of the household appliances can be improved.

The invention relates to the field of low-voltage power supply, in particular to a low-voltage current-limiting constant-voltage device. A current limiting reactor and a three-dimensional roll core autotransformer are connected in series with a low-voltage output end of a power distribution transformer, a multi-tap voltage regulator excitation winding is arranged an output end of the three-dimensional roll core autotransformer and has a plurality of shifts, each shift output is connected with a switch, and each switch is connected with a control chip. By means of current-limiting reactive characteristic, a surge can be absorbed, so that a large-current impact can be lagged, an instantaneous voltage drop of a system is reduced, the system stability is improved, an effect of filtering is achieved, a power factor of the system is improved, and meanwhile, the safety of the three-dimensional roll core autotransformer is protected.

The invention discloses a separated network transformer and transformation equipment. The split network transformer comprises at least one transmission element group for connecting a network chip and a network connector. And each transmission element group comprises a common mode inductor, a differential mode inductor, a first capacitor, a second capacitor, a third capacitor and a fourth capacitor. And the common-mode inductor is coupled with the network chip and is connected with the network connector through the third capacitor and the fourth capacitor so as to play a role in common-mode suppression and filtering. And the first capacitor and the second capacitor are coupled between the common mode inductor and the grounding end to play a role in filtering protection. The third capacitor and the fourth capacitor play a role in signal coupling and direct current isolation during signal transmission. The differential mode inductor is coupled between the network connector and the grounding end and plays a role in signal coupling and lightning surge protection, so that the stability and the reliability of the network transformer are improved.

The present invention relates to a parameter identification method of oil-paper insulation Debye circuit based on self-adaptive sampling interval Prony algorithm. The method improves the traditional Prony algorithm according to the physical characteristics of the Debye equivalent model depolarization current exponential function superposition. The sampling interval can accurately solve the time constant range, realize the adaptive selection of the sampling interval, and use the adaptive sampling interval to perform Prony fitting on the relaxation sub-spectral line of the corresponding time constant; after obtaining the sub-spectral line parameters, substitute it into Debye et al. The equivalent circuit parameter identification formula is used to realize the identification of equivalent circuit parameters. The inventive method avoids the subjectivity of artificial point selection and sampling interval selection, plays a filtering role on the measured depolarization current with noise interference, and accurately and uniquely realizes the identification of the Debye equivalent circuit parameters of the oil-paper transformer.