1195 results about "Negative voltage" patented technology

The invention belongs to the field of driving circuits of gallium nitride (GaN) power devices in motor driving or power electronic conversion, and discloses a design method of a three-level active driving circuit for restraining bridge arm crosstalk of a GaN device, and the method comprises the steps that a circuit is connected in a bridge type topological structure, and the bridge type topological structure comprises an upper bridge arm and a lower bridge arm which are the same in structure; the upper bridge arm and the lower bridge arm are both divided into two parts, namely a traditional driving circuit and an auxiliary circuit, and the auxiliary circuit is divided into a negative voltage self-recovery circuit and a crosstalk suppression circuit. According to the invention, a negative voltage self-recovery circuit and a crosstalk suppression circuit are formed by using the output and reverse conduction characteristics of the charge pump and the auxiliary GaN device. The advantages of the two methods are combined, the defects of a traditional method are effectively overcome, the turn-off speed is increased, the turn-off loss is reduced, and the positive and negative crosstalk is reduced while the turn-on speed is hardly influenced and the reverse turn-on loss is not additionally increased. The overall design is flexible, efficient and reliable.

A method and apparatus for the electrochemical polishing of metallic workpieces are proposed, wherein an electrolyte medium containing solid granular particles and a liquid electrolyte is placed in a container and conductively connected to a first electrode, wherein the metallic workpiece is conductively connected to a second electrode and immersed in the electrolyte medium in the container, wherein the electrodes are subjected to an electrical voltage such that the first electrode in contact with the electrolyte medium has a negative voltage and the second electrode in contact with the workpiece has a positive voltage, and wherein the workpiece is moved relative to the majority of solid granular particles of the electrolyte medium in order to polish it electrochemically.The invention provides that the polarity of the electrical voltage applied to the electrodes is temporarily reversed at least once, in particular periodically, during the electrochemical polishing of the workpiece, so that the first electrode in contact with the electrolyte medium temporarily has a positive voltage and the second electrode in contact with the workpiece temporarily has a negative voltage.

The invention relates to a safe starting control method, device, equipment and medium for a bootstrap drive inverter, and the method comprises the steps: obtaining a detection voltage representing an output filter inductance voltage after responding to any starting event and before formally transmitting a drive signal; comparing the negative voltage with a preset negative voltage safety threshold value; only when the detected voltage is higher than the safety threshold, a driving enable signal is generated to allow the inverter to be normally started; otherwise, generating a driving blocking signal, carrying out detection and judgment again after waiting for preset time delay, and circulating the process until the system state enters the safe area; the method is realized by modifying a control algorithm, no power hardware needs to be added, the starting impact risk is eliminated with low cost, and the contradiction between the hardware limitation of a bootstrap drive circuit and the negative residual voltage possibly existing on the output inductance of the inverter is solved; therefore, the safety problem of direct connection between the impact current and the bridge arm during starting in an unfavorable initial state is solved.

The utility model provides an insulated gate bipolar transistor driving circuit with adjustable positive and negative voltages, comprising a magnetic isolation module, the input end of which is connected with a driving signal and outputs an isolation driving signal; the input end of the first voltage regulating module is connected with the first positive voltage and outputs a second positive voltage within a first preset range; the input end of the second voltage regulating module is connected with the first negative voltage and outputs a second negative voltage within a second preset range; the push-pull output module is connected between the second positive voltage and the second negative voltage, the control end of the push-pull output module is connected with an isolation driving signal, and the output end of the push-pull output module is connected with the gate pole of the to-be-tested insulated gate bipolar transistor through a gate resistor; and the protection module is controllably connected between the output end of the push-pull output module and the second voltage regulation module under the action of the control signal. The driving circuit has the beneficial effects that the positive and negative voltage output capability can be flexibly adjusted according to debugging requirements, the working condition requirements of different clients are met, and the flexibility and adaptability of the driving circuit are improved.

A driver circuit for controlling a high-power switch. The driver circuit comprises a flyback converter having a positive output rail and a negative output. The driver circuit also comprises: a driving stage that is connected between the positive output rail and the negative output rail; a shunt regulator configured to regulate the negative output voltage on the negative output rail based on a difference between the negative output voltage and a target negative voltage value, wherein the shunt regulator is powered by the positive output voltage on the positive output rail; a short-circuit transistor having a conduction channel that is connected between the negative output rail and a ground terminal; and a regulation control circuit configured to: provide a short-circuit control signal to a control terminal of the short-circuit transistor in order to short the negative output rail to the ground terminal until the positive output voltage reaches a positive threshold.

In the present invention, a first control circuit (11) turns on a first switching element (Q1) when a negative voltage is applied, and generates a first control signal for turning off the transistor (Q1) when a positive voltage is applied. A second control circuit (12) turns on a second switching element (Q2) when a negative voltage is applied, and generates a second control signal for turning off the transistor (Q2) when a positive voltage is applied. When a positive voltage is applied to the first switching element (Q1), the first control circuit (11) supplies the second control circuit (12) with power for generating the second control signal. When a positive voltage is applied to the second switching element (Q2), the second control circuit (12) supplies the first control circuit (11) with power for generating the first control signal.

Embodiments of the invention includes various power supplies for plasma systems. These power supplies, for example, closes a switch to connect and disconnect a current pathway to cause an application of an asymmetric periodic voltage waveform. Where each cycle of the asymmetric periodic voltage waveform includes a first portion that begins with a first negative voltage and changes to a positive peak voltage, a second portion that changes from the positive peak voltage to a third voltage level and a fourth portion that includes a negative voltage ramp from the third voltage level to a fourth voltage level.

Disclosed herein is a single photon avalanche diode (SPAD) pixel circuit, including a SPAD having an anode coupled to a negative voltage and a cathode and a cascode transistor having a drain coupled to the cathode of the SPAD, a gate controlled by a cascode control signal, and a source. A readout circuit is coupled to the source of the cascode transistor and configured to detect a voltage change at the source of the cascode transistor and generate a pulse indicating an occurrence of an avalanche event. An active quenching circuit is coupled to the cathode of the SPAD and configured to detect an onset of the avalanche event and pull the cathode of the SPAD to a negative voltage to quench the avalanche event.

According to the pure hardware PID current control system and method based on the direct current brushless motor provided by the invention, the negative voltage interference generated by electromagnetic induction is directly filtered in the bus current signal acquisition stage through the cooperation of the current sampling module and the bus negative voltage elimination module; the problem of signal distortion caused by negative voltage in a traditional sampling circuit is eliminated, and the current effective value detection precision is improved; the PID control module constructed based on pure hardware calculates a difference value between a target voltage and an actual voltage in real time through an analog circuit, and generates a proportional, integral and differential composite compensation signal, so that a PWM modulation circuit can adjust duty ratio output in real time according to the compensation signal, and it is ensured that a bus current of a motor driver is rapidly converged to a target value; the whole scheme does not need to depend on a microcontroller and a complex software algorithm, closed-loop current control is achieved through discrete devices, and the system cost is reduced.

An enhancement mode gallium nitride (GaN) transistor configured to eliminate holes in the gate material under the gate metal. The transistor has four electrodes, namely a drain electrode, a source electrode, a gate electrode and a hole collector electrode. In a preferred embodiment, a negative voltage is applied to the hole collector electrode, attracting holes in the gate material under the gate metal. The attracted holes recombine with electrons supplied by the negative voltage, thereby substantially eliminating the holes.

The invention discloses a negative charge leakage circuit, a rapid chip negative charge leakage method and a radio frequency chip. The negative charge leakage circuit comprises a leakage circuit module and a control signal module, the bleeder circuit module comprises a first PMOS (P-channel Metal Oxide Semiconductor) tube, the source electrode of the first PMOS tube is grounded, and the drain electrode of the first PMOS tube is connected with the negative voltage potential of the chip; the input end of the control signal module is used for receiving an enable signal, and the output end of the control signal module is connected with the grid electrode of the first PMOS tube; the control signal module is used for outputting a corresponding control signal according to the received enable signal so as to control the first PMOS tube to be in a conduction state or a cut-off state; the first PMOS tube is used for discharging negative charges in the chip when the first PMOS tube is in a conducting state. According to the invention, the discharge speed of negative pressure in the chip can be improved, and the reliability of the chip in repeated power-on and power-off starting is improved.

The embodiment of the invention discloses a semiconductor device, a manufacturing method, a power module, a power conversion circuit and a vehicle. The semiconductor device includes a semiconductor body including a first surface, a second surface, a first device region, and a second device region; the first device region comprises a well region, a first region and a channel layer, and the first region is in contact with the channel layer; a gate trench; a first insulating layer; a first trench located in the second device region; the second device region further comprises a second insulating layer and a filling layer; a trench gate; an interlayer insulating layer; a Schottky metal layer; a drain electrode; and a source electrode. According to the technical scheme of the embodiment of the invention, the depletion type semiconductor device is formed and is in a conducting state and a cut-off state in a normal state, negative voltage needs to be applied between the grid electrode and the source electrode to cut off the channel, the response can be faster, the current circulation can be controlled, and the conducting loss is smaller. And a Schottky structure is integrated, so that the forward conduction voltage drop of the device is reduced, and the energy loss of the device in a reverse follow current state is reduced.

Provided are a gate driver and a display device including the same. The display device may include a display panel configured to display an image, a data driver configured to supply a data voltage to the display panel, a gate driver including a scan signal generation circuit configured to supply a scan signal to the display panel and a light-emitting signal generation circuit configured to supply a light-emitting signal to the display panel, and a clear signal line connected to the gate driver to deliver a clear signal in an alternating current form including a positive voltage and a negative voltage, wherein the gate driver initializes at least one of nodes of the scan signal generation circuit and nodes of the light-emitting signal generation circuit based on the clear signal.

The invention belongs to the technical field of electronic circuits, and provides a negative voltage charge pump circuit, a switching power supply converter and electronic equipment. A reference voltage generation module, a comparison module, a fourth driving module, a fifth power tube, a sixth power tube and a seventh power tube are additionally arranged on an existing charge pump. The reference voltage generation module is used for generating third reference voltage, namely threshold voltage when the negative-voltage charge pump circuit enters the light load, then the comparison module is used for comparing the third reference voltage with error voltage output by the error amplifier, and whether the negative-voltage charge pump circuit enters the light-load working condition or not is judged; when the negative-voltage charge pump circuit enters a light-load working condition, the large-size power tube and the driving module thereof are closed, and only the small-size power tube works, so that other performances of the negative-voltage charge pump circuit are ensured, the working current of the negative-voltage charge pump circuit in the light-load state is greatly reduced, and the working efficiency of the negative-voltage charge pump circuit is improved. Therefore, the conversion efficiency of the charge pump circuit in light load is improved.

The invention provides a CAN-FD wake-up circuit, a CAN transceiver and an electronic device, the CAN-FD wake-up circuit comprises a level shift module, an amplification comparison module and a wake-up identification module, the differential input end of the amplification comparison module is the source electrode of an NMOS tube, and the source electrode of the NMOS tube allows input of negative voltage, so the level shift module can process a CAN low level signal in a negative voltage range, and the wake-up identification module can process the CAN low level signal in the negative voltage range. Therefore, the input common-mode level range of the wake-up circuit of the CAN-FD is improved. On-off of the first switch is controlled based on whether the CAN transceiver is in a dormant state or a working state so as to control access of the second current source, and the output current of the second current source is a plurality of times of the output current of the first current source so as to increase the bandwidth of the amplification comparison module in the working state. Therefore, the amplification comparison module can be simultaneously applied to the dormant state and the working state of the CAN transceiver, so that the circuit cost is reduced.

The invention discloses a negative voltage clamping circuit and method. The negative voltage clamping circuit comprises a current mirroring module which is used for providing a reference current Iref and generating a corresponding reference current according to a preset current proportion mirroring; the voltage detection module is connected with the current mirror module and the negative voltage input end of the chip and is used for detecting the voltage VS of the negative voltage input end; and the clamping control module is connected with the current mirroring module and the voltage detection module, and the clamping control module is configured to be switched on when the voltage VS of the negative voltage input end exceeds a preset clamping threshold value and clamp the voltage VS of the negative voltage input end within a preset range. According to the negative voltage clamping circuit, the change of the negative voltage input end can be monitored in real time, it is ensured that the clamping control module responds rapidly when the voltage exceeds a threshold value, the negative voltage is limited within a safe range, circuit damage or performance reduction caused by too low voltage is avoided, and therefore the stability and reliability of a chip are improved.

The invention provides an output negative voltage protection circuit applied to an N-type power device linear voltage regulator. The output negative voltage protection circuit comprises a voltage comparator, a current comparator, an error amplifier, a buffer driver, a power device MP, a resistor R1, a resistor R2, a resistor Rload and a capacitor Cout. The method comprises the following steps: acquiring a voltage difference between an S-pole output voltage Vout of a power device MP and a reference voltage Vos through a voltage comparator, converting the voltage difference into a current signal Ieg, and comparing the current signal Ieg with a reference current Ios through a current comparator to generate a current signal Ilim; adjusting the output of an error amplifier according to the current signal Ilim, and dynamically adjusting the G pole voltage Vgate of the power device MP; when the output voltage Vout is lower than the reference voltage Vos, the G pole voltage Vgate is pulled down to turn off the power device MP through the current signal Ilim, and protection of the power device MP is achieved.

The ultralow frequency sensor comprises a vibration detection unit, a power supply voltage stabilization unit and a signal conditioning unit, the power supply voltage stabilization unit is provided with a low dropout linear voltage regulator U20, a voltage converter U19 and a negative voltage regulator U21, and the low dropout linear voltage regulator U20 stabilizes an external power supply as a positive power supply VCC; the voltage converter U19 is used for converting positive voltage of an external power supply into negative voltage and outputting stable negative power supply VEE through the negative voltage stabilizer; the positive power supply VCC and the negative power supply VEE supply power to the signal conditioning unit; the signal conditioning unit comprises a high common mode rejection differential amplifier, a differential-to-single-ended amplifier, a band-pass filter and a differential output driver, a differential signal output by the vibration detection unit sequentially passes through the high common mode rejection differential amplifier, the differential-to-single-ended amplifier, the band-pass filter and the differential output driver, and then a differential voltage signal is output; the method has the advantages of high stability and reliability and the like.

The embodiment of the invention provides a multi-output isolated power supply, which comprises a power transformer comprising a single primary side coil and a single secondary side coil; a switch driving circuit coupled to the primary coil to output a driving voltage to the primary coil based on the input voltage; a rectification circuit coupled to the secondary coil and configured to rectify a voltage across the secondary coil to output a first DC voltage at a first rectified voltage output end and a second DC voltage at a second rectified voltage output end; and an output unit coupled to the first rectified voltage output terminal and the second rectified voltage output terminal, the output unit comprising one or more low dropout linear regulator circuits, where an output terminal of a predetermined low dropout linear regulator circuit is coupled to the secondary circuit ground, the output unit is configured to output at least one positive voltage and at least one negative voltage with a voltage at an output terminal of a predetermined low dropout linear regulator circuit as a reference.

The application discloses a switch tube off negative voltage determination method and device and a switch tube driving control circuit. The switch tube off negative voltage determination method comprises the following steps: determining a first off negative voltage model and a second off negative voltage model; inputting the obtained off gate resistance, on gate resistance, bus voltage and minimum on voltage of the switch tube into the first off negative voltage model to obtain an upper limit absolute value of the off negative voltage of the switch tube; inputting the obtained off gate resistance, on gate resistance, bus voltage and maximum bearable negative voltage absolute value of the switch tube into the second off negative voltage model to obtain a lower limit absolute value of the off negative voltage of the switch tube; and determining the off negative voltage interval of the switch tube according to the upper limit absolute value and the lower limit absolute value. When the off negative voltage interval is used for negative voltage off control of the switch tube, the switch tube can be effectively prevented from being mis-opened, the switch tube can be protected, and the service life of the switch tube is prolonged.

The invention provides a silicon carbide driving circuit and a silicon carbide device, and relates to the technical field of power electronics. The silicon carbide device comprises driving circuits, an upper bridge arm and a lower bridge arm, each of the upper bridge arm and the lower bridge arm comprises a power switch tube, each driving circuit is connected with one power switch tube and is configured to drive the power switch tube to be switched on and switched off, and at least one driving circuit comprises a driving module, a driving resistor, a filtering module and a crosstalk suppression module; the driving module is configured to provide a driving signal for the power switch tube to drive the power switch tube to be switched on and off; the filtering module is configured to filter peak interference between the grid electrode and the source electrode of the power switch tube; and the crosstalk suppression module is configured to be switched on under the condition that the power switch tube is switched off and the voltage difference between the source electrode and the grid electrode of the power switch tube is greater than a preset threshold voltage so as to suppress a negative voltage crosstalk peak generated when the power switch tube is switched off. According to the invention, the negative voltage spike generated by the high-frequency switch can be effectively suppressed.

A bidirectional crosstalk suppression driving circuit suitable for a wide bandgap power semiconductor device comprises a push-pull circuit and a crosstalk suppression auxiliary circuit, the push-pull circuit is connected with the crosstalk suppression auxiliary circuit, and the crosstalk suppression auxiliary circuit is connected with a grid electrode and a source electrode of the power semiconductor device. The push-pull circuit is used for generating a driving voltage signal to drive a power semiconductor device. When the power semiconductor device is subjected to positive crosstalk, positive voltage is generated through a negative voltage capacitor in the crosstalk suppression auxiliary circuit, and the influence of negative overvoltage generated on a driving resistor when the positive crosstalk occurs is reduced; when the power semiconductor device is subjected to negative crosstalk, gate equivalent driving impedance is reduced through an RD auxiliary branch in the crosstalk suppression auxiliary circuit, and reverse overvoltage caused by negative crosstalk is reduced. The circuit has compatibility and economical efficiency, and is simple in structure and easy to operate. The method is of great significance in improving the turn-on and turn-off reliability of a power semiconductor device and guaranteeing stable operation of a system.

The invention discloses a dual-channel voltage clamping circuit, a chip and electronic equipment, and the dual-channel voltage clamping circuit comprises a first voltage clamping circuit which is connected with a to-be-clamped position and is used for clamping the voltage of the to-be-clamped position to a positive voltage clamping value when the voltage of an input signal is in a first voltage range, and a second voltage clamping circuit which is connected with the to-be-clamped position and is used for clamping the voltage of the to-be-clamped position to a negative voltage clamping value when the voltage of the input signal is in a second voltage range; the second voltage clamping circuit is connected with the to-be-clamped position and used for clamping the voltage of the to-be-clamped position to a negative voltage clamping value when the voltage of the input signal is in a second voltage range; wherein the voltage in the first voltage range is greater than the voltage in the second voltage range, and wherein the negative voltage clamp value is full amplitude adjustable. According to the dual-channel voltage clamping circuit, at least the negative voltage clamping value can be flexibly adjusted to meet different requirements, positive and negative voltage clamping is achieved through dual channels, the positive and negative voltage clamping does not affect each other, and the accuracy of the positive and negative voltage clamping is ensured.

The invention provides a voltage stabilizer based on voltage conversion, a control method and a storage medium, and the voltage stabilizer comprises a PFC chopping boost circuit which receives an input alternating current and a boost duty ratio, carries out the chopping boost of the input alternating current based on the boost duty ratio, and outputs a high-voltage chopping alternating current signal; the positive and negative half-cycle filter circuit is connected with the PFC chopping booster circuit and is used for rectifying and filtering the high-voltage chopping alternating-current signal to obtain a positive voltage-stabilizing chopping alternating-current signal and a negative voltage-stabilizing chopping alternating-current signal; the positive and negative half-cycle voltage reduction and stabilization circuit is connected with the positive and negative half-cycle filter circuit, receives the voltage reduction duty ratio, and performs voltage reduction and stabilization on the positive voltage stabilization chopping alternating current signal and the negative voltage stabilization chopping alternating current signal based on the voltage reduction duty ratio to obtain a preset actual positive electric signal and a preset actual negative electric signal; and the output voltage merging circuit is connected with the positive and negative half-cycle voltage reducing and stabilizing circuit, and integrates the preset actual positive electric signal and the preset actual negative electric signal to obtain a voltage stabilizing electric signal. According to the invention, the voltage fluctuation is quickly responded at low cost.

The invention discloses a negative voltage driving circuit, a chip, electronic equipment and a vehicle, and belongs to the technical field of circuits. The negative voltage driving circuit comprises a monitoring module, a digital logic control module and a negative voltage generation module, the monitoring module is used for collecting a first working parameter of a transistor and transmitting the first working parameter to the digital logic control module; and the digital logic control module is used for determining a target negative voltage turn-off mode for the transistor according to the first working parameter, and controlling the negative voltage generation module to generate a corresponding negative voltage according to the target negative voltage turn-off mode. According to the technical scheme, the monitoring module collects the working parameters of the transistor in real time, the digital logic control module determines the optimal target negative voltage turn-off mode for the transistor according to the working parameters collected in real time, and then the negative voltage generation module is controlled to rapidly and accurately generate the negative voltage. And the driving requirements of the transistor under different working conditions can be quickly responded.

The invention discloses a high-side driving circuit applied to a gallium nitride fully-integrated half-bridge power chip, and belongs to the field of power integrated circuits. The circuit comprises an input stage circuit, an anti-VSW negative voltage shift circuit and a low-power-consumption output stage circuit. Wherein the anti-VSW negative voltage shift circuit guarantees correct transmission of a signal under a VSW node negative voltage condition through a negative voltage transmission structure, and in addition, the anti-VSW negative voltage shift circuit can generate an advanced pulse control signal for the low-power-consumption output stage circuit; and the low-power-consumption output stage circuit only charges the bootstrap capacitor in a short time before the output state is changed through the advanced pulse control signal, so that the problem of high power consumption of a capacitor charging branch in a traditional scheme is greatly relieved. According to the invention, the signal transmission reliability of the high-side driving circuit under the negative-voltage working condition is remarkably improved, the static power consumption is effectively reduced, and the high reliability and low power consumption requirements of the gallium nitride fully-integrated half-bridge driving chip on the high-side access are considered.

The invention relates to the technical field of flexible direct-current power transmission, and discloses a direct-current power stabilizing device of an MMC bridge arm cascade dual-port switching type energy storage module. Two ends of an upper bridge arm and a lower bridge arm of the MMC are respectively connected with a dual-port switching type energy storage module in series, and the MMC is connected with a positive electrode and a negative electrode of a direct current bus through the dual-port switching type energy storage modules. The dual-port switching type energy storage module comprises a bipolar DC / DC converter, the bipolar DC / DC converter is provided with two output ports, the voltage polarity (positive voltage or negative voltage) of the output ports can be switched according to the surplus or vacancy condition of the direct current side power, rapid charging and discharging control of the energy storage module is achieved, and therefore the direct current side power fluctuation is effectively stabilized, and the stability of the voltages at the two ends of the MMC is maintained. According to the invention, the stability is improved and the power is stabilized while the work of the MMC is not influenced, and the switching loss and the cost are effectively reduced.

The invention relates to the technical field of flexible direct current power transmission, in particular to a reconfigurable bipolar switchable energy storage system and a control method thereof, and the system comprises an energy storage unit which comprises a battery; the input end of the energy conversion unit is connected to the energy storage unit, and the energy conversion unit is used for converting the stored energy into bidirectional direct-current electric energy; the input end of the polarity switching unit is connected to the output end of the energy conversion unit, and the polarity switching unit is used for switching the voltage polarity of the output port; and the control unit is used for respectively sending driving signals to the energy conversion unit and the polarity switching unit. According to the invention, the problem that the switching between the positive voltage output and the negative voltage output is completed according to the surplus or vacancy condition of the direct current side power in the large-scale renewable energy access power grid is effectively solved, and the rapid charging and discharging control of the energy storage system is realized, so that the direct current side power fluctuation is effectively stabilized, and the stability of the voltages at the two ends of the MMC is rapidly maintained.

The invention discloses a multi-electric-level straight drive circuit of a depletion type switching device, which is characterized in that by dynamically switching positive voltage, zero voltage and deep and shallow negative voltage, the positive voltage is utilized to reduce on resistance in a conduction stage, the deep negative voltage is utilized to quickly cut off current in a turn-off stage, and then the shallow negative voltage is switched to maintain a turn-off state, so that the static power consumption is remarkably reduced. A surge suppression circuit and a power driver work cooperatively, surge current is suppressed through a current-limiting resistor and a fast bypass switch at the moment of starting, and a short circuit Ra is formed after negative voltage is established to reduce loss; and before power failure, the capacitor stored energy is released through the active discharge switch, so that mistaken switching-on caused by residual voltage is eliminated. Through system-level innovation, the direct connection problem of a depletion type device is effectively solved, and a high-efficiency, reliable and compact solution is provided for a high-power-density power supply system.

The invention discloses a preparation method of a piezoelectric response type hybrid ceramic membrane, which is characterized in that polyvinylidene fluoride powder is used as a base material of the membrane, propylene carbonate or ethylene carbonate is used as a diluent, negative-voltage-loaded piezoelectric ceramic modified nanoparticles are doped, and a proper amount of inorganic piezoelectric nanoparticles are doped, so that the electrical property of the pressed membrane is remarkably improved; a negative charge group introduced to the surface of the membrane through surface grafting is combined, so that the relative content of beta crystal forms of the polyvinylidene fluoride membrane is increased, and finally efficient interception and excellent anti-pollution effects on humic acid are achieved.