Patents
Literature
Patsnap Eureka AI that helps you search prior art, draft patents, and assess FTO risks, powered by patent and scientific literature data.

1728 results about "Square waveform" patented technology

A square wave is a non-sinusoidal periodic waveform in which the amplitude alternates at a steady frequency between fixed minimum and maximum values, with the same duration at minimum and maximum.

Balanced charging method and apparatus for battery pack, and computer program product

Provided in the present application are a balanced charging method and apparatus for a battery pack, and a computer program product. Charging current control consists of two stages, i.e., a "pulse square-wave excitation" stage and a "multi-stage current-reduction charging" stage. During the pulse square-wave excitation stage, the parameter identification of an equivalent circuit model and the joint estimation of state variables are realized, thereby providing reliable battery parameters for a subsequent balancing process. During the multi-stage current-reduction charging stage, a flyback converter is used to control a balanced current of each battery cell, and the battery cells remain in a charging state throughout a balancing process, thereby effectively mitigating the impact of a hysteresis voltage.
Owner:CHINA FAW CO LTD

Repair circuit, display panel and display equipment

The invention provides a repair circuit, a display panel and display equipment. The repairing circuit comprises a dedelay unit, an input end of which is connected with a grid electrode to-be-repaired signal and an output end of which is electrically connected with a first node; the input end of the shaping unit is electrically connected to the first node, and the output end is electrically connected to the second node; the input end of the inverting unit is electrically connected to the second node, and the output end is electrically connected to the third node. The de-delay unit is used for processing the grid signal to be repaired according to the clock signal and outputting a de-delay signal, so that the falling edge of the de-delay signal is consistent with the falling edge of the clock signal; the shaping unit is used for processing the rising edge waveform of the dedelayed signal and outputting a square wave signal opposite to the dedelayed signal in phase; and the inverting unit is used for performing inverting processing on the square wave signal and outputting a grid electrode repairing signal. The repairing circuit can effectively repair abnormal grid signals in the display panel, and the product yield is improved.
Owner:HKC CORP LTD

Arc fault detection method and device based on voltage time difference variation

The invention discloses an arc fault detection method and device based on voltage time difference variation, and belongs to the technical field of low-voltage power distribution network fault protection, and the method comprises the steps: enabling an arc fault point to be equivalent to an arc voltage source, and employing an arc voltage change rate and an arc voltage effective value, establishing detection feature description of a fault waveform generated by the arc voltage source, wherein the fault waveform presents a square-wave-like waveform; sampling adjacent cyclic wave voltages of a load side monitoring point, performing feature identification on the tail end voltage difference between adjacent cyclic waves based on detection features, and identifying a first fault waveform; and after the first fault waveform occurs, performing continuous identification counting on the arc faults, realizing identification of the continuous arc faults by using the difference between the non-fault waveform before the fault occurs and the waveform to be identified, and confirming the occurrence of the arc faults. The detection method is good in reliability, clear in physical significance, high in detection sensitivity, not affected by line parameters, capable of achieving detection only through a single monitoring point and lower in cost.
Owner:SHANDONG UNIV OF TECH +3

Colored electronic paper energy-saving driving design method and system based on optimized square wave driving

The invention relates to a color electronic paper energy-saving driving design method and system based on optimized square wave driving, and belongs to the technical field of electronic paper display. The method comprises the following steps: firstly, based on a displacement time relation model of charged particles in the color electronic paper microcapsule, determining an optimal driving voltage interval of the particles, and generating a square wave driving waveform library; secondly, the environment temperature is monitored in real time, and square wave driving waveform parameters are dynamically adjusted; thirdly, analyzing statistical characteristics of the input image, dividing content complexity and distributing driving voltage grades; and finally, identifying an image change area through a frame difference algorithm, and performing local refreshing or global refreshing to realize image display. According to the color electronic paper energy-saving driving design method and system based on optimized square wave driving, an efficient and cooperative temperature compensation mechanism and a dynamic voltage adjusting strategy are combined, the display quality is maintained, meanwhile, the driving energy consumption of the color electronic paper is effectively reduced, and it is ensured that the color electronic paper is kept effective and stable in various temperature environments.
Owner:FUZHOU UNIV

New energy automobile wireless power supply soft switching control system based on segmentation strategy

The invention discloses a new energy automobile wireless power supply soft switching control system based on a segmentation strategy, and particularly relates to the technical field of new energy automobile wireless power supply, and the control system comprises a resonance current zero-cross detection module which detects a resonance current output square wave signal of a resonance network in real time; the segmented control decision module is used for selecting a strong control strategy or a weak control strategy according to a comparison result of the smoothed frequency difference value and a preset threshold value; the segmented control execution module is used for adjusting the inverter driving frequency by adopting a corresponding control algorithm according to the output of the segmented control decision module; according to the new energy automobile wireless power supply soft switching control system based on the segmentation strategy, the segmentation control logic and the model and algorithm of the special module are designed, so that the driving frequency of the new energy automobile is adjusted, and the driving frequency of the new energy automobile is adjusted to be within the preset frequency locking range. And wide-range frequency locking, rapid dynamic correction and high-precision steady-state control are realized.
Owner:JILIN TEACHERS INST OF ENG & TECH

FPGA (Field Programmable Gate Array)-based dedicated chip real-time evaluation method

The invention relates to the technical field of real-time kernel performance testing of special chips, in particular to a special chip real-time performance evaluation method based on an FPGA (Field Programmable Gate Array), which comprises the following steps: (1) aiming at a real-time system on an ASIC (Application Specific Integrated Circuit) chip, setting an external interrupt source and an interrupt service program through a hardware interrupt controller; (2) two tasks with the same priority are created, scheduling of the tasks is achieved through time slice rotation, and a real dynamic load scene is simulated; (3) configuring an external FPGA (Field Programmable Gate Array) to generate a square wave signal to trigger external interruption of the ASIC chip, receiving a feedback signal, and connecting the FPGA and the GPIO through an external physical connecting line to form a hardware interruption triggering-response closed loop; and (4) realizing nanosecond timestamp capture through a counter built in the FPGA, acquiring time delay data, calculating interrupt response time, and transmitting the time delay data to a PC (Personal Computer) through a UART (Universal Asynchronous Receiver / Transmitter) to calculate a maximum value, a minimum value, an average value and a data jitter range of test data. The method can effectively solve the problem that the traditional internal closed-loop test cannot reflect the real interruption randomness and the dynamic load.
Owner:FUDAN UNIVERSITY

Excitation signal generation method and system and digital eddy current sensor

The embodiment of the invention provides an excitation signal generation method and system and a digital eddy current sensor, and the method comprises the steps: outputting a square wave signal through a pulse width modulation assembly of a microcontroller unit, and enabling the frequency and resolution of the square wave signal to be adaptive to eddy current probes with different inductance values; inputting the square wave signal into a low-pass filter for filtering, and setting the cut-off frequency of the low-pass filter, the suppression times of higher harmonics and the attenuation slope so as to output a sine wave signal with a target total harmonic distortion range; the amplitude of the sine wave signal is collected in real time, and the pulse width modulation duty ratio and the passband gain of a low-pass filter are dynamically adjusted in combination with a digital control algorithm, so that the sine wave signal is subjected to self-adaptive adjustment and correction and is output; and taking the sine wave signal as an excitation source of an eddy current probe, and driving the eddy current probe to carry out nondestructive testing. According to the invention, the excitation signal which gives consideration to high-frequency signal generation, deep harmonic suppression and digital adaptive adjustment can be generated.
Owner:XIAN THERMAL POWER RES INST CO LTD +1

High-adaptability fused salt heat storage system in-situ monitoring method

The invention relates to a high-adaptability fused salt heat storage system in-situ monitoring method, which is characterized in that current and potential signals correspond to the concentration of impurity ions in fused salt through an electrochemical analysis method, and the current value of a characteristic peak corresponds to the concentration of impurities in the fused salt, so that sampling and chemical analysis are not needed; according to the method, the real-time concentration of the impurities can be obtained only by acquiring the characteristic peak current value through electrochemical scanning, the fused salt component analysis process is greatly simplified, the real-time monitoring of the ion concentration through the square wave voltammetry is an automatic and continuous process, and compared with a traditional analysis method, the method has the advantages of being high in sensitivity and analysis speed and suitable for popularization and application. And analyzable response can be generated to tiny concentration change. According to the invention, in-situ and continuous measurement of the concentration of the marker impurities in the molten salt can be realized, and timely and accurate feedback can be provided for changes of components and heat storage performance of the molten salt.
Owner:ZHEJIANG UNIV +1

Transformer partial discharge positioning method and device based on bushing CT acquisition

The invention provides a transformer partial discharge positioning method and device based on bushing CT acquisition. The method comprises the following steps: acquiring a high-frequency partial discharge pulse signal of a current transformer at a transformer bushing; background noise of the pulse signal is removed, amplitude correction is carried out, and a corrected pulse signal is obtained; judging whether the partial discharge belongs to external interference or internal partial discharge based on the polarity distribution rule of the corrected pulse signal; if the interference is external interference, comparing the amplitudes of the correction acquisition signals corresponding to the bushings, and taking the position corresponding to the current transformer with the maximum amplitude as an interference source injection position; if partial discharge occurs in the transformer, calculating the distance proportion from the partial discharge position to the head end of the winding according to the attenuation characteristic of the pulse signal propagating in the winding and the pre-injected calibration square wave signal so as to determine the discharge position. According to the method, the method for determining the partial discharge position of the transformer is simplified, external interference and internal partial discharge signals can be quickly identified, and misoperation of a protection device is avoided.
Owner:NORTH CHINA ELECTRICAL POWER RES INST +2

Anti-pinch detection circuit and motor device

The utility model relates to an anti-pinch detection circuit and a motor device, the anti-pinch detection circuit comprises a sampling circuit, a differential amplification circuit, a ripple signal conversion circuit, a low pass filter circuit and a controller, the sampling circuit samples a ripple current signal of a vehicle window motor to obtain a corresponding voltage sampling signal, and the voltage sampling signal is sent to the differential amplification circuit; the differential amplification circuit carries out differential amplification on the voltage sampling signal to obtain a voltage amplification signal, the voltage amplification signal is divided into two paths, one path is converted into square wave signals through the ripple signal conversion circuit, the controller determines the position of a car window according to the number of the square wave signals, and the other path is subjected to low-pass filtering through the low-pass filtering circuit to obtain the voltage amplification signal. If the position of the car window is located in the preset anti-pinch area, the controller determines whether the car window is locked or blocked or not according to the amplitude of the low-frequency ripple signal. The anti-pinch detection circuit adopts two-path detection, so that the influence of environment or other factors on the ripple current signal is avoided, further anti-pinch misjudgment is avoided, and the anti-pinch detection accuracy is improved.
Owner:SHENZHEN H&T AUTOMOTIVE ELECTRONICS TECH CO LTD

Sine constant current source excitation method for eddy current displacement sensor

The invention discloses an eddy current displacement sensor sine constant current source excitation method, and belongs to the technical field of sensor measurement and control. The method comprises the following steps: S1, generating positive and negative symmetric reference voltages through a reference voltage source circuit; s2, outputting a square wave control signal with adjustable frequency by the control chip, and driving a switching circuit to generate a square wave taking the positive and negative reference voltage as a level; s3, processing the square wave through a filter circuit to obtain a standard sine wave voltage signal; and S4, converting the sine voltage signal into sine constant current source excitation through a Howland current source circuit, and outputting the sine constant current source excitation to a sensor probe coil. According to the invention, through combination of digital control and analog conversion, the circuit structure is simplified, the cost is significantly reduced, and convenient adjustment of the output frequency and high stability and precision of the output current are realized at the same time.
Owner:HUNAN AEROSPACE ELECTROMECHANICAL EQUIP & SPECIAL MATERIAL INST

Aero-engine rotating speed measuring device

The embodiment of the invention discloses an aero-engine rotating speed measuring device which is characterized by comprising a tachogenerator module, a hardware conditioning module, a high-speed A / D conversion module, a data picking and buffering module, a digital signal processing module, a rotating speed measuring module, a power supply module, an operation control module and a communication module which are connected in sequence. The tachogenerator module converts an acquired engine rotating speed signal into a sine-wave-like alternating-current voltage signal of which the frequency and the amplitude are positively correlated with the rotating speed. The hardware conditioning module is used for conditioning the sine-like signal with a relatively wide amplitude range into a signal meeting the amplitude range requirement of the high-speed A / D conversion module; the high-speed A / D conversion module performs high-speed sampling on the conditioned sinusoidal-like signal and converts the conditioned sinusoidal-like signal into a digital signal; the data picking and buffering module is used for picking and buffering the digital signals subjected to A / D conversion; the digital signal processing module is used for converting the digital signal into a digital square wave signal; the rotating speed measuring module is used for monitoring the frequency of the digital square wave signal and calculating the rotating speed of the engine through the frequency; and the communication module is used for uploading the engine rotating speed measurement result to the flight control computer. The technical scheme of the invention solves the problem.
Owner:XIAN AERO ENGINE CONTROLS

High signal-to-noise ratio inductive detection method and system for non-ferromagnetic oil liquid scraps

The invention belongs to the induction type oil abrasive dust sensor technology, and particularly discloses a non-ferromagnetic oil abrasive dust high signal-to-noise ratio induction type detection method and system, and the method comprises the following steps: a microcontroller carries out the control, and sends an instruction to two waveform generation chips through the microcontroller; dual-signal generation: generating two waveform and phase-adjustable periodic signals based on two waveform generation chips; the square wave frequency mixing is used for introducing a square wave as a parameter control signal to carry out frequency mixing operation; and frequency mixing difference adjustment: the optimal signal-to-noise ratio of different non-ferromagnetic chip signals is obtained by adjusting the frequency mixing difference. The frequency mixing difference between the induction signal and the reference signal can be accurately controlled, especially for non-ferromagnetic chips, different frequency mixing differences are adopted to improve the chip signal-to-noise ratio, meanwhile, square waves are introduced to serve as the reference signal to improve the chip signal amplitude, the phase shift process is simplified, the stability of the circuit is improved, and reliable data are provided for subsequent chip signals.
Owner:SUZHOU RENZHENG ZHITAN TECH CO LTD

Automatic frequency locking circuit based on time-to-voltage converter and phase-locked loop

The invention provides an automatic frequency locking circuit based on a time-to-voltage converter and a phase-locked loop, and relates to the technical field of phase-locked loops, a first frequency-halving unit and a second frequency-halving unit respectively carry out frequency-halving processing on a reference signal and a frequency division signal of a current comparison period to obtain a first square wave signal and a second square wave signal; the first square wave signal and the second square wave signal are transmitted to the time-to-voltage converter; the time voltage converter comprises a phase generation unit, a first charge pump and a second charge pump, the phase generation unit generates an enable signal according to the first square wave signal and the second square wave signal, and the first charge pump and the second charge pump respond to control of the enable signal and collect single pulse signals from the first square wave signal and the second square wave signal respectively so as to supply power to the input end of the comparator; the comparator compares power supply voltages of the two input ends to achieve frequency comparison of the reference signal and the frequency division signal. And selection in a plurality of phase signals is not needed, and required digital circuit modules are reduced, so that the delay of the reference signal and the frequency division signal in the conversion process is reduced.
Owner:PEKING UNIV

Low-power-consumption winch sensor based on tunneling magnetoresistance effect

The invention discloses a low-power-consumption winch sensor based on a tunneling magnetoresistance effect. The low-power-consumption winch sensor comprises a measurement module, a signal conversion unit, a shell, a mandrel, a magnetic rotary disc and a detection assembly. The magnetic turntable and the mandrel are connected and rotate synchronously, the detection assembly comprises a TMR sensing element and N magnets, and the magnetic turntable is provided with mounting blind holes for embedding the magnets; the TMR sensing element is arranged on the shell and comprises a mounting plate and two sensing units, the magnetic domain directions of the two sensing units are perpendicular to the rotation axis, magnetic resistance signals of the two sensing units are converted through the signal conversion unit and input into the measuring module, the horizontal distance between the centers of the two sensing units and the magnet and the rotation axis is R, and the center distance L of the two sensing units is smaller than R * sin (180 degrees / N); the sensor is based on the TMR tunneling magnetoresistance effect, is high in detection sensitivity and low in energy consumption, outputs square wave signals with phase differences, can be used for a measurement module to accurately analyze and calculate the rotating speed and the rotating direction of a winch roller, is simple in overall structure, small in radial size and easy to install, and the installation precision is controlled.
Owner:TIANJIN LUHAI PETROLEUM EQUIP SYST ENG CO LTD

Analog quantity isolation transmission device and method based on transformer

The invention discloses a transformer-based analog quantity isolation transmission device and method. The transformer-based analog quantity isolation transmission device comprises an analog quantity input module, a symmetric square wave transformation module, a transformer module, a rectifier module and an analog quantity output module, the analog quantity input module is used for inputting analog quantity; the symmetrical square wave conversion module is used for converting the input analog quantity into symmetrical alternating-current square waves; the transformer module is used for transmitting the converted alternating-current square wave from the primary side of a transformer to the secondary side of the transformer, and isolation of analog quantity is achieved through the transformer; the rectifier module is used for rectifying the alternating-current square wave isolated by the transformer to realize analog quantity reduction; and the analog quantity output module is used for outputting analog quantity. According to the invention, the analog quantity can be directly transmitted based on the transformer.
Owner:DALIAN TAISMAN TECH CO LTD

High-voltage direct-current line EM lightning arrester valve plate shunting non-uniformity test system and method

The invention discloses a high-voltage direct-current line EM lightning arrester valve plate shunting non-uniformity test system and method, and belongs to the technical field of lightning arrester performance test.The method comprises the steps that S1, a high-voltage direct-current power transmission system simulation model is established, and the discharge current of an EM lightning arrester under the severe working condition of single-pole line short circuit is evaluated based on the high-voltage direct-current power transmission system simulation model; adopting square-wave pulse approximate discharge current, and determining the total amplitude and square-wave pulse width of long-wave discharge current of the EM lightning arrester; s2, applying the square wave pulse to the tested EM lightning arrester resistor discs through a shock wave test platform, and testing the current magnitude and the total current of each resistor disc of the EM lightning arrester under the working condition; the total amplitude and the square wave pulse width of the preset square wave pulse are the same as the total amplitude and the square wave pulse width of the long wave of the discharge current of the EM arrester; and S3, according to the current of each resistor disc and the total current, calculating a current non-uniform coefficient and the current range of the resistor discs. According to the invention, the current distribution non-uniformity of the multi-column parallel lightning arrester can be tested and evaluated more reasonably and comprehensively.
Owner:POWER RES INST OF STATE GRID SHAANXI ELECTRIC POWER CO LTD +1

Test method and device for examining broadband measurement performance of capacitor voltage transformer

The invention relates to a test method and device for examining broadband measurement performance of a capacitor voltage transformer. The method comprises the following steps: frequency response test: acquiring sine wave voltage signals and first output voltage signals output by the capacitor voltage transformer to be tested for multiple times; processing the signals at different frequency points to obtain gain, phase characteristics and steady-state response capability at each frequency point; a square wave signal transmission test: collecting a square wave voltage signal and a second output voltage signal output by the capacitor voltage transformer to be tested; carrying out signal time-frequency domain analysis to obtain rapid voltage change transient response capability and broadband measurement accuracy; an operation / lightning impulse transmission test: collecting a transient operation / lightning impulse wave voltage signal and a third output voltage signal output by the capacitor voltage transformer to be tested; signal processing is carried out, and the response capability and high-frequency measurement accuracy of the transient high-frequency voltage signal are obtained; and the broadband measurement performance is obtained. Compared with the prior art, the method has the advantages of comprehensively examining the broadband measurement performance of the capacitor voltage transformer and the like.
Owner:STATE GRID SHANGHAI MUNICIPAL ELECTRIC POWER CO

Common-mode interference resistant active pen and touch screen interaction system and signal demodulation method

The invention discloses an active pen and touch screen interaction system resistant to common-mode interference and a signal demodulation method. The system comprises a signal receiving terminal and a signal transmitting terminal. The signal transmitting terminal modulates data to be transmitted by adopting a differential binary phase shift keying modulation method, and transmits a generated modulation signal to the signal receiving terminal; the analog front-end receiving module is coupled with the signal transmitting terminal, receives the modulation signal and outputs a digital square wave signal after fidelity extraction processing; and the digital demodulation processing module performs differential coherent digital demodulation on the digital square wave signal based on the prior characteristics of the modulation signal, inhibits residual noise and recovers data to be sent. The analog front end focuses strong common-mode noise suppression and analog filtering, the digital demodulation algorithm performs secondary digital purification by using signal time sequence characteristics, and the two constructs an efficient anti-interference pipeline. Meanwhile, the regular square wave signals can be directly processed through differential coherent demodulation, and the requirements for performance and power consumption of a rear-end processor are lowered.
Owner:SHANGHAI HYNITRON TECH CO LTD

Flow measurement method of external clamping type ultrasonic flowmeter using synchronous acquisition mode

The invention provides a flow measurement method of an external clamping type ultrasonic flowmeter using a synchronous acquisition mode, which comprises the following steps of: simultaneously driving an upstream transducer and a downstream transducer to transmit signals by current signals from a function generator, and recording received signals of the transducers on the same time window; after ultrasonic signals synchronously collected by the transducer are subjected to time domain and frequency domain analysis, filtering processing and amplification processing, a function generator is used for converting and outputting square waves, and then the square waves are output to different channels after being digitalized through a multi-channel oscilloscope; by analyzing the digital square waves, ultrasonic forward and reverse flow propagation time and time difference are calculated, and then the flow is calculated by combining a time difference method measurement principle with measurement pipeline section parameters. According to the external clamping type ultrasonic flowmeter, an active synchronous acquisition mode is used, the two transducers are driven at the same time and receive signals, ultrasonic waves pass through fluid with the same temperature and flow profile, and therefore the time difference measurement deviation and the flow calculation error of the external clamping type ultrasonic flowmeter are reduced.
Owner:CHONGQING ACAD OF METROLOGY & QUALITY INST

Active clamping resonant drive circuit and device

The invention discloses an active clamping resonant drive circuit and device. The active clamping resonant drive circuit comprises a power supply module, an energy storage clamping module, a switch group module, an additional capacitor module and an output drive module. The device corresponds to the circuit. According to the application, through the energy storage clamping module and the combination of the switch group module, wide-range duty ratio adjustment of quasi-square wave driving output can be realized under the frequency of tens of megahertz, duty ratio requirements of different working conditions can be adapted, frequency band work with a certain width can be supported through the same set of circuit parameters, and the design flexibility of the ultrahigh frequency power converter is greatly improved; the circuit redesign cost in different frequency scenes is reduced; through the energy storage clamping module, the coupling degree of a driving waveform and line parasitic parameters is effectively reduced, so that the driving circuit still has good stability during high-frequency work, the anti-interference capability is enhanced, the adverse effect of the parasitic parameters or external interference on the driving performance is avoided, and the reliability of high-frequency work of the power electronic switching device is guaranteed.
Owner:HUNAN UNIV +1

Parameter identification-based synchronous reluctance motor full-speed-domain position-sensorless control method

The invention discloses a parameter identification-based synchronous reluctance motor full-speed-domain position-sensorless control method, which relates to the technical field of motor control, and is characterized in that when a motor is in a zero-low-speed domain, a pulsating square wave voltage signal injection method is adopted to realize effective observation of a rotor position and good dynamic response performance; when a rotating speed transition interval is entered, an improved weighted switching strategy is adopted, so that the motor can smoothly switch two control strategies in the interval; when the motor enters a medium-high speed domain, rotor position angle observation is carried out by adopting a model reference adaptive control method, and high steady-state operation precision is achieved; however, in the whole operation process, inductance parameters influenced by magnetic circuit saturation and cross saturation are nonlinear, online identification is carried out by adopting a model reference adaptive method, and the estimation precision of the rotor position angle is improved.
Owner:HEFEI UNIV OF TECH

Multi-parameter adjustable ultrasonic transducer excitation circuit system

The invention discloses a multi-parameter adjustable ultrasonic transducer excitation circuit system which is simple in structure and flexible to control. According to the technical scheme, the device comprises a central control module, an ultrasonic waveform generation module, a program control voltage source module and a full-bridge driving module; the central control module at least has a serial port communication function, and receives a parameter setting instruction of an upper computer through serial port communication to control the whole system; the ultrasonic waveform generation module comprises a sine wave generation module and a pulse square wave conversion module, the sine wave generation module generates a sine wave signal with a specified frequency, and then the pulse square wave conversion module generates a pair of square wave waveforms which are opposite in phase and are emitted in a pulse group mode; the waveform basic frequency of the square wave is equal to that of the sine wave, the pulse frequency and width of the pulse train are adjustable, and the pair of inversion signals is used for controlling two half-bridges of the full-bridge driving module.
Owner:INST OF WENZHOU ZHEJIANG UNIV

Voltage-to-current circuit, calibration method, multi-range calibration method and power supply

The invention discloses a voltage-to-current circuit, a calibration method, a multi-range calibration method and a power supply, a power amplification unit adopts MOS tubes of different channel types to match with working voltages of opposite polarities, and a bias circuit is combined to superpose exclusive bias, so that the waveform adaptation limitation of a traditional circuit is broken through, and the voltage-to-current conversion efficiency is improved. Alternating current, direct current, triangular waves, square waves and other special waveforms can be stably output, and the adaptability is greatly improved; secondly, pure hardware signal transmission and feedback are carried out in the whole process, the intermediate link of MCU measurement-setting is omitted, multi-stage error accumulation is effectively reduced, output delay is remarkably reduced, and the response speed is higher; in addition, the current sampling feedback unit and the error amplification unit form closed-loop control, power amplification output current is sampled in real time and fed back for calibration, and the precision and stability of the output current are effectively improved. Meanwhile, the bias circuit accurately regulates and controls the conduction state of the MOS tube, the linearity and consistency of current output are improved, and the overall structure is simple and reliable.
Owner:HUNAN NEXT GENERATION INSTRUMENTAL T&C TECH CO LTD

Method and system for plasma process

A method for generating a bias voltage includes generating a radio frequency (RF) sinusoidal wave voltage, generating a DC square wave voltage, and forming a bias waveform by synchronizing the RF sinusoidal wave voltage and the DC square wave voltage. The method further includes providing the bias waveform to an electrode of a plasma processing system.
Owner:TOKYO ELECTRON LTD

Dual three-phase permanent magnet synchronous motor maximum torque current ratio control method and system based on virtual signal injection

The invention discloses a dual three-phase permanent magnet synchronous motor maximum torque current ratio control method and system based on virtual signal injection, and the method comprises the steps: injecting a bipolar square wave signal into a current vector angle, and calculating the d-q axis current after the bipolar square wave signal is injected through the current vector angle of the bipolar square wave signal; the d-q axis current after the bipolar square wave signal is injected is substituted into the corrected torque equation, the positive polarity torque Tup and the negative polarity torque Tdown of the dual three-phase permanent magnet synchronous motor are calculated and are expanded according to the Taylor series, when the difference between the Tup and the Tdown expanded according to the Taylor series is equal to 0, the difference between the Tup and the Tdown passes through a PI controller and then is superposed with an initial current vector angle beta, and the initial current vector angle beta is obtained. And obtaining a current optimal current vector angle, and calculating a d-q axis reference current required by the dual three-phase permanent magnet synchronous motor. According to the invention, accurate control of the maximum torque current ratio is realized.
Owner:JIANGSU UNIV

Control circuit and method for three-phase wireless power transmission system to supply power to single-phase load

The invention discloses a control circuit and method for a three-phase wireless power transmission system to supply power to a single-phase load. The method comprises the following steps: setting the frequency, amplitude and electrical angle of a three-phase voltage; determining the input voltage of the direct-current power supply; a proportional resonance (PR) controller is used for processing input voltage of a direct-current power supply and three-phase instantaneous voltage input by a transmitting and receiving coil module, and control signals are obtained after processing; inputting the control signal into a three-phase high-frequency inverter and a modulation circuit module to generate a square wave signal conforming to a set three-phase voltage phase; inputting the square wave signal into a resonance compensation module to generate a three-phase sinusoidal voltage wave which is the same as the set three-phase voltage; the three-phase sinusoidal voltage wave is subjected to wireless electric energy transmission through the transmitting and receiving coil module to obtain a corresponding square wave signal; corresponding square wave signals are converted into sinusoidal voltage waves through the rectifying and filtering module and are transmitted to a system load. According to the invention, the transmission power of the three-phase wireless power transmission system can be improved.
Owner:CHINA UNIV OF MINING & TECH

Chip interface safety protection control circuit

The invention discloses a chip interface safety protection control circuit, which relates to the technical field of chip interface protection, and comprises a power supply control module which is used for carrying out rectification filtering and voltage stabilization processing on accessed electric energy, meeting power supply requirements, carrying out overcurrent detection, constant current regulation and overcurrent power-off protection control, and carrying out power-off protection on the power supply control module during power-off protection. The interface voltage of the chip module is lowered, the interface sampling module can carry out sampling and peak detection on pulse signals accessed or output by the chip module, the state detection module can judge the type of the pulse signals, namely square wave pulses or sine pulses, and the first sampling module and the second sampling module carry out peak sampling according to the type of the pulse signals. The micro-control module controls the threshold value setting module to set a comparison threshold value, then the abnormity detection module detects the peak value state of the pulse signal, and when the peak value state is larger than the normal peak value state, chip interface protection is carried out. The chip interface safety protection control circuit can automatically carry out interface signal detection and interface protection control.
Owner:SHENZHEN HISTONE OPTOELECTRONICS TECH CO LTD

Method and device for dynamically setting dog feeding time of watchdog circuit

PendingCN120994432AFault responseHardware monitoringSquare waveformReactive system
The invention discloses a method for dynamically setting dog feeding time of a watchdog circuit, which comprises the following steps of: collecting and monitoring power consumption of a CPU (Central Processing Unit) and a corresponding load, and fitting the load and power of the CPU according to monitoring data so as to reflect the running state condition of a system; power consumption of a monitoring CPU is collected in real time, the real-time CPU load is calculated according to the fitting relation between the CPU load and power, and the watchdog feeding time of a watchdog circuit is determined according to the CPU load; a square wave period is set, square waves are collected to set timeout time, and the timeout time is kept consistent with dog feeding time, determined according to CPU loads, of a watchdog circuit. According to the method, the CPU power consumption and the load are fitted, the CPU load is monitored in real time, the square wave period is adjusted, the dog feeding time is dynamically adjusted according to the CPU load, resource waste is avoided, and the method is suitable for the fields of embedded systems, industrial control and the like.
Owner:NANJING SCIYON AUTOMATION GRP

Electromagnetic noise suppression control method for multi-phase self-excitation synchronous motor

The invention discloses an electromagnetic noise suppression control method for a multi-phase self-excitation synchronous motor. A driving system of the synchronous motor comprises a double-closed-loop control system and an inverter. The specific method comprises the steps that the double-closed-loop control system outputs voltage reference signals of all coordinate axes, and all the coordinate axes are arranged in an electromechanical energy conversion plane and a non-electromechanical energy conversion plane respectively; injecting the square wave signal into a selected coordinate axis, and cooperatively adjusting excitation and noise values by using the positive correlation between excitation current and the amplitude of the square wave and the negative correlation between the excitation current and the frequency of the square wave; and then outputting the adjusted voltage reference signal, processing the adjusted voltage reference signal and other voltage reference signals, and outputting the processed voltage reference signal and other voltage reference signals to an inverter to generate a driving voltage. Therefore, the square wave amplitude is synchronously increased and the excitation current is kept stable when the noise reduction of the square wave frequency is improved by utilizing the quantitative relation that the excitation current is positively correlated with the square wave amplitude and negatively correlated with the square wave frequency, so that the load capacity of the synchronous motor is prevented from being reduced.
Owner:FUJIAN AGRI & FORESTRY UNIV