61results about How to "Prevent self-oscillation" patented technology

The invention discloses an active capacitive stylus and a touch detection and feedback drive method thereof. The active capacitive stylus comprises a conductive point, a signal processing module and a capacitor. The conductive point is used for detecting a touch screen drive signal transmitted by a touch screen and sending a feedback drive signal output from the signal processing module. The signal processing module is used for processing the touch screen drive signal received by the conductive point and generating a synchronous feedback drive signal. The capacitor is arranged between the conductive point and the signal processing module. During detection, the capacitor is used for coupling the touch screen drive signal acquired by the conductive point to the input end of the signal processing module. When the touch screen is in feedback drive, the capacitor is used for isolating the feedback drive signal. By the touch detection and feedback drive method, the purpose of positioning the position of the conductive point of the active capacitive stylus accurately is achieved.

An X-band high gain and high efficiency triaxial relativistic klystron amplifier comprises a cathode holder 301, a cathode 302, an anode outer cylinder 303, an inner conductor 304, a modulation cavity305, a first reflection cavity 306, a first cluster cavity 307, a second reflection cavity 308, a second cluster cavity 309, a third reflection cavity 310, an extraction cavity 311, a cone waveguide312, a feedback loop 313, an electron collector 314, a support rod 315, a microwave output port 316, a solenoid magnetic field 317, and an injection waveguide 318, wherein the overall structure is rotationally symmetric about the central axis OZ axis. The amplifier, by rationally designing the electromagnetic structure of the device, overcomes the shortages such as complex structure, and relatively low gain (about 40 dB), efficiency (less than 30%) and output microwave power (about 1 GW) of axial injection or lateral dual-port injection in the existing X-band triaxial relativistic klystron amplifier, and realizes the high-gain, high-efficiency, and high-power microwave output of the triaxial relativistic klystron amplifier in the X-band.

The present invention provides a receiving / transmitting switching device which is used for realizing the receiving / transmitting switching of the TDD wireless communication system. The receiving / transmitting switching device comprises a power amplifier, a low-noise amplifier and a circulator, and also comprises the following components: a quarter-wave microstrip which is used for impedance conversion and has a first end connected to the third port of the circulator and a second end connected to the input end of the low-noise amplifier; a first switching element which has a negative pole connected to the third port of the circulator and a positive pole connected to the first end of the inductor; a second switching element which has a negative pole connected to the second end of the quarter-wave microstrip and a negative pole earthed; a load resistor which absorbs the reflected wave of the transmitted signal and the leakage signal of the circulator and coverts to heat energy, wherein the first end of the load resistor is connected to the positive pole of the first switching element and the second end is earthed; and an inductor which operates a high resistance function to the radio frequency through the direct current bias thereby guaranteeing that the low-noise amplifier will not be damaged by the large signal at any working time.

A first drive control signal regenerating circuit outputs an ON timing drive signal at turn-ON of a main switch element, and a second drive control signal regenerating circuit generates an OFF timing drive signal at turn-OFF of the main switch element. A rectifying switch controlling switch element connected between the gate and source of a rectifying switch element is driven by an output of the second drive control signal regenerating circuit. An output of the first drive control signal regenerating circuit connects to the gate of a commutating switch controlling switch element, which connects to one end of an auxiliary winding, the other end thereof being connected to the gate of a commutating switch element. Accordingly, the rectifying switch element is directly controlled from the primary side.

The embodiment of the invention discloses an insulated gate bipolar translator (IGBT) chip. The IGBT chip comprises a grid pad and a grid bus, and further comprises a compensation resistance region which is positioned between the grid pad and the grid bus. According to the IGBT chip, the compensation resistance region is added between the grid pad and the grid bus, the resistance of the compensation resistance region equals to the grid resistance of the IGBT chip, and the size of the compensation resistance can be regulated according to the requirements of the IGBT chip for preventing the self excited oscillation of an IGBT modular circuit. The compensation resistance region is positioned below the grid pad, so the inner area and volume of the IGBT chip cannot be occupied, moreover, the compensation resistance region is integrated in the chip during the production process of the IGBT chip, the forming process of the compensation resistance only needs to be added during the production process of the IGBT chip, so the production method of the IGBT chip is simple and practicable, and the design cost of the circuit is not increased.

The invention provides a self-driven synchronous rectification power supply and a switching-off method thereof. The self-driven synchronous rectification power supply comprises a switching-off control unit, a control value acquisition unit and a secondary control unit, wherein the switching-off control unit is configured to prolong the turning-on time of a primary master switch of a transformer in response to a switching-off signal of the power supply; the control value acquisition unit is configured to acquire a control value corresponding to a voltage-second product of the primary input voltage of the transformer in the turning-on time; and the secondary control unit is configured to detect the control value and to control the on / off of a synchronous rectifier on the secondary side of the transformer according to the control value. In the invention, the power supply can be switched off effectively to avoid self oscillation, has a small area and a simple structure, and is cost-saving and convenient to mount.

The invention belongs to the field of high-performance terahertz radiation sources, and provides an extended interaction klystron and a production method thereof. The extended interaction klystron comprises an input resonant cavity, an output resonant cavity, and N intermediate resonant cavities. The input resonant cavity is communicated with an input waveguide. The output resonant cavity is communicated with an output waveguide. Electron beam channels communicated with one another are arranged at the centers of the input resonant cavity, the output resonant cavity and the N intermediate resonant cavities. The cycle lengths of the resonant clearances of the N intermediate resonant cavities are different or partially different. N is a positive integer greater than 1. The problem that the existing extended interaction klystron has a very narrow working band and high in-cavity power density is solved. An electron beam is tuned by different resonant frequencies when passing through the intermediate resonant cavities. Thus, the working bandwidth of the whole device is improved.

The circuit includes power amplifier to amplify emission signal up to emission power, circulator to couple its first port with the amplifier for exporting amplifier output power to the second port of the circulator in order to let antenna emit it, low noise amplifier to couple with circulator third port to receive signal inputted from the second port of the circulator through receiving antenna and to amplify the received signal, control unit consisting of actuating circuits for the power amplifier and the low noise amplifier to cut off the power amplifier at the time of receiving signal and to cut off the low noise amplifier at the time of emitting signal.

There is provided a flay-back type synchronous rectifying switching power supply device in which a rectifying element is surely turned off before the main switch is turned on even when the on-time of a main switch element is lengthened due to sudden variation of a load. The synchronous rectifying switching power supply device is equipped with a synchronous rectifying element (Q 2 ) connected to a secondary winding (N 2 ) of a transformer (T) in series and driving means comprising an auxiliary winding (N 3 ), etc. for turning on the synchronous rectifying element (Q 2 ) complementarily with a main switch element (Q 1 ) between output terminals ( 13, 14 ). A transistor (Tr 1 ) serving as interrupting means for turning off the synchronous rectifying element (Q 2 ) is provided between the gate and source of the synchronous rectifying element (Q 2 ). An off-timing at which the synchronous rectifying element (Q 2 ) is turned off by the interrupting means (Tr 1 ) is set within a timing range which corresponds to a fixed time after the main switch element (Q 1 ) is turned on and also is as near as a fixed driving period of the main switch element (Q 1 ).

The invention relates to a Rogowski coil for measuring nanosecond pulse current. The Rogowski coil comprises an ultracrystalline magnetic core and a copper belt wound on the ultracrystalline magnetic core. And the ultracrystalline magnetic core and the copper belt are arranged in an annular shielding outer shell; an integrating resistor is formed by connecting a plurality of carbon film resistors in parallel, and the carbon film resistors connected in parallel are arranged in the shielding outer shell. The Rogowski coil for measuring nanosecond pulse current can measure the nanosecond pulse current, the test effect of the Rogowski coil is good in actual use, the Rogowski coil can maximumly test current pulses with the leading edge being several nanoseconds, and current amplitude of several kilo-amperes can be measured.

The invention relates to a device and method for suppressing earth leakage and common-mode interference of a cable of a differential resistance sensor. The device comprises a controllable constant current differential excitation circuit, an error amplification circuit and a differential measurement circuit which are connected in sequence, the controllable constant current differential excitation circuit is an excitation and differential measurement circuit with high impedance characteristic relative to the ground, so that influence of residual ground noise interference is presented as common-mode interference; residual common-mode interference is removed by the high common-mode rejection ratio characteristic of the differential measurement circuit; and the voltage between the potential value of the common end of the two resistor arms of the differential resistance sensor and the ground potential is forced to be almost zero through the error amplification circuit. Thus, the current flowing through the earth leakage impedance of the cable core is almost zero, the leakage current and the noise interference current are greatly reduced, the current flowing through the two resistor armsof the differential resistance sensor is ensured to be equal to each other to the greatest extent, and the accuracy of a resistance ratio measurement value is ensured.

The invention provides a spatial field power supply suitable for a Sipm (Si photomultiplier). The spatial field power supply suitable for the Sipm comprises a flyback power conversion topology, a rectifying and filtering circuit, an operational amplifier, a DA chip, a PNP type triode, and an NPN type triode; the operational amplifier, the DA chip, and the triodes form a linear adjustment circuit,low voltage at an input end is converted into high voltage through the flyback power conversion topology, then the high voltage is taken as input of the linear adjusting circuit after being subjectedto filtration through the rectifying and filtering circuit, current flowing through the triodes is controlled by utilizing the DA chip and the operational amplifier, the linear amplification characteristic of the triodes is utilized at the output end, and linearly adjustable high voltage is outputted from the output end of the linear adjustment circuit. The spatial field power supply suitable forthe Sipm realizes continuously adjustable and wide-ranged high voltage output.

The embodiment of the invention discloses a laser device. The laser device comprises a laser light source for shooting out a laser beam with circular light spots, wherein the diameter of the circular light spots is d; and an elliptical soft-edge aperture used for homogenizing the laser beam, wherein the above laser beam shoots into the soft-edge aperture at an incidence angle beta and beta is larger than 0 degree and smaller than 90 degrees. The long axis a of the elliptical soft-edge aperture is larger than or equal to d / cos beta and the short axis b of the elliptical soft-edge aperture is larger than or equal to d*cos beta. According to the technical scheme of the invention, not only all laser spots are homogenized by the soft-edge aperture, but also the laser self-excited oscillation phenomenon caused by the reflection of the soft-edge aperture in the vertical direction can be avoided. Therefore, the beam shaping effect is ensured to be good, and the output energy is ensured to be high at the same time.

The invention discloses a continuous adjustable DC stabilized power supply circuit with 0V minimum output voltage based on a three terminal regulator. The circuit comprises a three terminal regulator and a load. The anode of a filtering capacitor C1 is connected with the anode output end of an external input power supply and the input end Vin of the three terminal regulator. The cathode of the filtering capacitor C1 is connected with a power ground GND. One end of an adjustable resistor R2 is connected with the adjusting end ADJ of the three terminal regulator. The other end of the adjustable resistor R2 is connected with the power ground GND. One end of a divider resistor R1 is connected with the adjusting end ADJ of the three terminal regulator, and the other end is connected with the output end Vout of the three terminal regulator. The anode of a diode D1 is connected with the output end Vout of the three terminal regulator, and the cathode of the diode D1 is connected with the anode of a diode D2. The cathode of the diode D2 is connected with the anode of the filtering capacitor C2. The cathode of the filtering capacitor C2 is connected with the power ground GND. Two ends of the load are respectively connected with two ends of the filtering capacitor C2. The circuit has beneficial effect of 0V minimum output voltage and is continuous adjustable.

The invention relates to large-energy laser impulse amplification system with saturated absorption body, which comprises a laser oscillator, an amplifier, and said body on light path between oscillator and amplifier with opposite wave length as laser. This invention overcomes the problem that system has huge volume and can not prevent interstage couple and eliminate impulse bottom noise synchronously.

The invention discloses a dual-gradually-changed transitional waveguide applied to a millimeter and higher frequency point coupled cavity traveling-wave tube. The transitional waveguide is equipped with a first port and a second port, wherein the width L1 of the first port is greater than the width L3 of the second port; and the height L2 of the first port is greater than the height L4 of the second port. By adoption of the transitional waveguide, the reflection of the waveguide input end and the waveguide output end is effectively restrained, and self-oscillation caused by matching defects is overcome.

The invention relates to a slab laser amplifier and a laser output method. The slab laser amplifier comprises a gain dielectric module, pumping modules, and a reflector module, wherein the reflector module comprises two reflectors which are located on the left and right sides of the gain dielectric module; the pumping modules are located on the front and rear sides of the gain medium module; laser crystals are 0.5-1.5mm thick and include one doped laser crystal and two non-doped laser crystals; the two non-doped laser crystals are bonded to the two long and high surfaces of the doped laser crystal without adhesive, respectively, and arranged in parallel with the doped laser crystal; after seed laser is incident into the laser crystals at a certain angle, the seed laser is reflected back and forth between the reflectors, and meanwhile, passes through the laser crystals between the reflectors, and finally, the power amplified laser can be output. The bonded laser crystals of an ultrathin slab structure are taken as the gain dielectric of the slab laser amplifier, the thermal effect of the laser crystals is reduced and the gain effect of the gain dielectric is improved; high-output power and high-beam quality continuous or pulse laser amplified output can be obtained.

The invention discloses a lath laser amplifier and a laser output method thereof. The lath laser amplifier comprises a seed laser module, a pump module, a gain medium module and a dichroic-mirror module; the pump module, the dichroic-mirror module and the gain medium module are arranged side by side, and the seed laser module is arranged on one side of the modules arranged side by side; the lath laser amplifier further comprises a diffusion collimating module; the gain medium module comprises a laser crystal and two cooling heat sink blocks, the laser crystal is a doped laser crystal and is in adhesive-free bonding with two non-doped laser crystals, and the thickness of the laser crystal ranges from 0.5mm to 1.5mm. The bonded laser crystal of an ultra-thin lath structure is utilized as a gain medium of the laser amplifier, two-way amplification is achieved by adopting the diffusion collimating module, heat effect of the laser crystal is reduced, the surface damage threshold of the laser amplifier is increased, laser gain extraction efficiency is increased, and continuous or pulse laser amplification output high in output power and beam quality can be acquired.

The invention discloses a digital radio frequency mixed domain signal source based on PXI bus control. A cover plate and a shielding cavity are arranged on two sides of a shell, a digital board is arranged between the shell and the cover plate, and a radio frequency board is arranged between the shell and the shielding cavity; the radio frequency board is connected with an upper computer through a PCI interface, the upper computer sends information to the FPGA on the radio frequency board, and a soft core in the FPGA processes a PCI protocol and then bidirectionally communicates with the upper computer through the PCI protocol; the FPGA generates a radio frequency CW signal through a phase-lock loop (PLL), the radio frequency CW signal is divided into two paths after being filtered by a switch, the two paths of radio frequency signals are respectively modulated and amplified, are coupled into one path of radio frequency signal through the coupler and then are sent to the detector, and the radio frequency signal is conditioned and then is sent to an AD. On the basis of a PXI framework, analog digital signals and radio frequency signals are integrated, and signal output of a mixed domain is achieved.

The invention provides a resonant cavity and a terahertz extended interaction oscillator of a cross structure. The terahertz extended interaction oscillator of the cross structure is greatly differentfrom a traditional terahertz extended interaction oscillator. In a conventional device, a longitudinal electric field is distributed in one direction (such as an x-direction or a y-direction) in a concentrated manner; while a longitudinal electric field is distributed in two directions (i.e., the x-direction and the y-direction) at the same time in the device of the cross structure. Therefore, inthe structure, the energy exchange efficiency of the longitudinal electric field and the cylindrical electron beam can be effectively enhanced, and the output power can be effectively improved. The device can work under the working conditions of 14kV and 0.1 by optimally designing the cross extended interaction oscillator working at 0.3 THz, and the power output of about 51.5 W can be realized. The cross structure is suitable for improving the output power of the terahertz extended interaction oscillator, and is particularly suitable for improving the engineering realizability and the workingstability of a device under lower working current.

The invention discloses a high-energy 1.0[mu]m laser amplification system with 100ns pulse width. The system employs a 1.0[mu]m DFB semiconductor laser as a seed source so as to obtain high-stabilitysingle-frequency laser output. The system utilizes an optical fiber amplification module for chopping, the continuous seed source is chopped into pulse laser with a Lorentz waveform rising edge through an acoustic optical modulator, and finally the width of laser pulse is continuously widened through the amplification effect of a rear-stage solid amplification module, so that 1.0[mu]m pulse laserwith the pulse width greater than 100ns is obtained. According to the invention, the single frequency and stability of 1.0[mu]m laser are ensured, and a new technical route is provided for coherent detection radar to adopt a 1.0[mu]m laser light source through the characteristic that the laser pulse width is gradually broadened through the laser amplification effect.

The invention relates to a controlled starting circuit which comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor, a second capacitor, a first diode, a first voltage-stabilization pipe, a second voltage-stabilization pipe, a first transistor, a second transistor, a PWM starting circuit, a controllable precision voltage-stabilization source and a transformer winding. The controlled starting circuit is simple in structure, light in weight and easy to minimize, delay time exists between inputting of external signals and starting of the PWM starting circuit, and the delay performance can effectively prevent self-excitation vibration.

The invention discloses a cascading normal shock switching power supply, and is provided with a main transformer which is provided with a primary main coil (Np) and a secondary main coil (Ns1); a first main switch (Q1); a second main switch (Q2); a control circuit; a first rectification element (CR2), wherein the negative electrode is connected to a connection point of the first main switch (Q1) with the primary main coil (Np), and the positive electrode is connected to a low potential side of an input DC voltage; a second rectification element (CR1), wherein the positive electrode is connected to a connection point of the second main switch (Q2) with the primary main coil (Np), and the negative electrode is connected to a high potential side of the input DC voltage; and a rectification circuit in a mode of synchronization rectification. When there is a voltage at an output end and the switching operation of the first and second main switches are stopped, the control terminal of any one of the first and second main switches is set in a mode of continuously connection and a positively biased voltage is applied to the control terminal. According to the invention, the device can prevent the continuous self-oscillation of the output end when there is a voltage (energy source) at the output end.

The invention provides a spatial filter, which comprises a first window sheet and a second window sheet along a longitudinal axis, wherein a laser beam is incident into the first window sheet and transmitted from the second window sheet so as to get out of the spatial filter; and at least one of the first window sheet and the second window sheet is perpendicular to the longitudinal axis. The invention also provides a laser amplification device with the spatial filter.

The invention provides a resonance suppression method for a humanoid flexible arm, particularly provides a resonance suppression method for a humanoid flexible arm based on a PR controller, and belongs to the field of vibration control. An output shaft of a joint motor end of the humanoid flexible arm is connected with a fixed end of an arm connecting rod through a harmonic reducer, and the inherent flexibility of a flexible gear of the harmonic reducer introduces a resonance frequency point to cause the resonance problem of the humanoid robot arm. According to the resonance suppression methodfor the humanoid flexible arm, the PR controller is introduced into a control system of the humanoid flexible arm, the disturbance suppression capability of the PR controller at a specific frequencypoint is utilized, so that the resonance caused by the fact that the output signal frequency of the controller is equal to the resonance frequency of the humanoid flexible arm is avoided, and the operation performance and the stability of the humanoid flexible arm are improved.

The invention is applicable to the technical field of electric control, and particularly provides a control method for preventing abnormal manual steel pouring of a reversible H-shaped steel universalbeam roughing mill set. The control program of the method comprises the following steps: setting the functional blocks FCYSDC01-FCYSDC15 as a determiner unit for abnormal manual steel pouring of thereversible H-shaped steel universal beam roughing mill set; and setting FCYSDC06, FCYSDC08, FCYSDC10 and FCYSDC16-FCYSDC22 as a manual speed control unit under the abnormal manual steel pouring stateof the H-shaped steel universal beam roughing mill set. When an abnormal manual steel pouring state occurs; the control program firstly decelerates and stops the three-frame main transmission of the universal beam roughing mill set. After setting the time of the three-frame shut-down, the setting value of the manual operation joy-stick output speed of the H-shaped universal beam roughing set is enabled (the setting value is shown in the description). During the period of time of abnormal manual steel pouring forced interruption, the roughing unit can have enough time to process the rolled pieces which normally stay in the universal roughing mill set, thereby thoroughly avoiding the violent self-excited oscillation of the three-frame main transmission of the universal beam roughing mill setcaused by sudden abnormal manual steel blocking slippage.

The invention discloses a circuit structure with a signal amplification function. The circuit structure comprises an amplifier, a transformer, a second resistor, a third resistor, a fourth resistor, a first capacitor, a third capacitor and a signal source, wherein a third pin and a fourth pin of the amplifier are connected to both ends of a secondary coil of the transformer; both ends of a primary coil of the transformer are connected to both ends of the signal source; a slide tap is arranged on the primary coil of the transformer; a fourth pin of the amplifier is connected to one end of the third resistor; the other end of the third resistor is connected to a fifth pin of the amplifier; both ends of the third resistor are connected to the first capacitor in parallel; and the fifth pin of the amplifier is taken as an output end of the amplifier. The slide tap is arranged on the primary coil of the transformer, so that the signal input strength is changed, and a feedback resistor is connected to the capacitor in parallel, so that the purposes of improving the operational amplifier stability and preventing the self-excitation shock are realized.

The invention discloses a switching power supply unit which includes a rectifying unit with a synchronous rectifying mode. The rectifying circuit is provided with a rectifying switch connected in series with a secondary coil of a main transformer and conducted synchronously with a conduction period of a main switch; and a commutation switch connected in parallel with the secondary coil and conducted synchronously with the conduction period of the main switch. The switching power supply unit is provided with an auxiliary switching circuit. The auxiliary switching circuit detects the generated self-oscillation when voltage flows across an output end and the main switch stops switching, and enables the commutation switch to be turned off to prevent continuous self-oscillation. The switching power supply unit can prevent continuous self-oscillation generated when the main switch is turned off.

The invention discloses an open circuit protection circuit for self-ballasted fluorescence. The open circuit protection circuit comprises a silicon controlled rectifier SCR1, a bidirectional diode DB2, a winding N4 and a rectifier bridge BR1, wherein the anode of the silicon controlled rectifier SCR1 is connected with the positive electrode of an external power source, the cathode of the silicon controlled rectifier SCR1 is connected with the negative electrode of the external power source, the control electrode of the silicon controlled rectifier SCR1 is connected with the bidirectional diode DB2 in series and then connected with the sampling voltage output end, the winding N4 and a primary feedback winding N2 of a self-ballasted fluorescence lamp are coupled to form a transformer, the two ends of the winding N4 are connected with the two alternating current input ends of the rectifier bridge BR1, one direct current output end of the rectifier bridge BR1 is connected with the negative electrode of the external power source, and the other direct current output end of the rectifier bridge BR1is connected with the anode of the silicon controlled rectifier SCR1. By the adoption of the open circuit protection circuit, self-exciting oscillation of the circuit can be rapidly stopped when loads of the self-ballasted fluorescence lamp circuit are in an open circuit, and the open circuit protection effect is achieved.

The invention discloses a bias circuit capable of improving the charge collection efficiency of a pole plate, and relates to the technical field of circuit design. The bias circuit is characterized in that W7805 is an integrated serial voltage stabilizer which is a three-terminal integrated voltage stabilizing device with the output voltage being 5V. The integrated serial voltage stabilizer is provided with three pins in total, wherein the pin 1 is an input terminal, the pin 2 is an output terminal, and the pin 3 is a voltage regulating terminal which is called a regulating terminal in short. The bias circuit adopts a MAX641 chip produced by a MAXIM company in America, wherein the MAX641 chip is a step-up DC-DC converter and is also a CMOS constructed external pressure switching voltage stabilizer. The power consumption is low, and the input and output range is wide. The bias circuit provided by the invention can adjust output voltage of the MAX641 chip.