221 results about "Forward current" patented technology

A method protects against fault arcs in an electric power distribution system in which electric power from an electric feed point is distributed via a common superordinate main distribution line and from the common main distribution line via multiple subordinate output lines. The main distribution line can be interrupted by a main switch, and each of the output lines can be interrupted by a paired output switch. A fault arc current threshold which, when exceeded by a fault arc current of a fault arc, is a precondition for triggering the main switch is matched to the maximum forward current and / or the output trigger duration of the output switches such that a fault arc is quenched selectively either by one of the output switches or by the main switch before the energy released by the fault arc exceeds a specified energy threshold.

Unidirectional hybrid switch. At least one example is a method operating a hybrid switch, the method comprising: sensing a voltage across an upper terminal and a lower terminal of the hybrid switch, the hybrid switch is forward biased when the upper terminal has higher voltage, and the hybrid switch is reverse biased when the lower terminal has higher voltage; when the hybrid switch is forward biased, selectively conducting a forward current from the upper terminal to the lower terminal by sharing the forward current between a FET switch and a BJT switch, the selectively conducting when a control terminal is asserted; and when the hybrid switch is reversed biased, non-selectively conducting a reverse current from the lower terminal to the upper terminal.

Provided is a display device comprising a display panel including a display area and a non-display area and an electrostatic protection circuit disposed in the non-display area. The electrostatic protection circuit includes a first stage circuit including a (1-1)-th diode which causes a forward current to flow from a first node to a second node and a first capacitor and a first resistor connected in parallel to the (1-1)-th diode, a second stage circuit including a (2-1)-th diode which causes a forward current to flow from the second node to a third node and a second capacitor and a second resistor connected in parallel to the (2-1)-th diode, and a third stage circuit including a (3-1)-th diode which causes a forward current to flow from the third node to a fourth node and a third capacitor and a third resistor connected in parallel to the (3-1)-th diode.

The invention discloses a current sampling circuit and a current sampling method based on a gallium nitride power tube, and belongs to the technical field of circuits. A temperature compensation module in the current sampling circuit can ensure that the on-resistance proportions of a silicon sampling tube and an upper tube / a lower tube are kept consistent in different temperature ranges; when the upper tube is conducted, the first temperature compensation module controls the first negative feedback module to generate a positive current or a negative current in proportion to a sampling current, the first current mirror image module outputs the positive current or the negative current to the sampling module, and the sampling module calculates the sampling current of the upper tube according to the positive current or the negative current; when the lower tube is switched on, the second temperature compensation module controls the second negative feedback module to generate a positive current or a negative current in proportion to the sampling current, the second current mirror image module outputs the positive current or the negative current to the sampling module, and the sampling module calculates the sampling current of the lower tube according to the positive current or the negative current. According to the invention, temperature compensation can be carried out, and bidirectional current sampling can be realized.

The invention discloses a Ga2O3 SBD trap test method based on forward current transient response, and belongs to the field of semiconductor device reliability. Comprising the following steps: giving a filling voltage interval and a filling time interval of a Ga2O3 SBD trap filling stage; giving a bias condition and a test time interval of a trap test stage; giving a normalization processing method and range of the forward current transient response; a characterization range of a Ga2O3 SBD device level trap time constant is given. The transient response curve of the forward current of the Ga2O3SBD under the constant test voltage is collected, and the transient current variation caused by the trap is evaluated through a normalization processing method. And repeatedly testing under the condition of multiple groups of filling voltages, establishing a time constant spectrum of the trap by using a structure function method, and extracting a time constant parameter of the trap in the Ga2O3SBD to realize in-situ and online Ga2O3SBD trap test. The method is suitable for evaluating the trap effect of Ga2O3 SBD devices from different manufacturers, and can realize spectral valuation characterization of Ga2O3 SBD traps and in-situ and nondestructive testing of trap parameters.

In an MMC-type power conversion device, a control device calculates an evaluation value representing the degree of variations in voltage of capacitors of individual converter cells. When this evaluation value exceeds a threshold value, the control device controls the converter cells as follows: (i) when current in a positive direction flows through a first converter cell with a voltage of the capacitor greater than a mean value, reducing an output time of positive voltage, (ii) when current in a negative direction flows through the first converter cell, increasing an output time of positive voltage, (iii) when current in the positive direction flows through a second converter cell with a voltage of the capacitor smaller than a mean value, increasing an output time of positive voltage, or (iv) when current in the negative direction flows through the second converter cell, reducing an output time of positive voltage.

The invention discloses a micro-copper pillar bump interconnection resistor electromigration degradation prediction method. The method comprises the following steps: obtaining the net flux of Cu atoms in a Cu6Sn5 layer and a Cu3Sn layer and the net flux of Ni atoms in a Ni-Cu-Sn compound layer under forward current and reverse current; establishing a relationship between the net flux of Ni atoms and the thickness change of the Ni-Cu-Sn compound layer and a relationship between the net flux of Cu atoms and the thickness change of the Cu6Sn5 layer and the Cu3Sn layer; establishing a thickness polarity growth model of the Ni-Cu-Sn compound, the Cu6Sn5 layer and the Cu3Sn layer; establishing a thickness polarity consumption model of the Cu bonding pad, the Sn solder and the Ni layer; and establishing a resistance electromigration degradation model of micro-copper pillar bump interconnection. According to the method, the electromigration degradation prediction of the interconnection resistor of the copper pillar bump plated with the Ni layer can be realized, and a large amount of service life and time and economic cost generated by a failure analysis test are greatly reduced or avoided.

The invention discloses a method for measuring and analyzing residual magnetism characteristics of an iron core. According to the method, a to-be-detected iron core is demagnetized, preset residual magnetism is set, direct-current voltage excitation with opposite polarities, the same amplitude and the same duration is applied to a primary winding of the to-be-detected iron core, and transient current response signals are synchronously collected; two groups of current under positive / negative polarity excitation are extracted, and the residual magnetism direction is judged by comparing the change rate of the current; a curve of equivalent resistance changing along with time is calculated based on forward current and voltage, a resistance value corresponding to a characteristic inflection point moment is selected, the resistance value is substituted into a pre-established residual magnetism-equivalent resistance empirical formula to deduce the magnitude of residual magnetism, and a matched iron core residual magnetism detection and demagnetization integrated system integrates information management, residual magnetism detection, demagnetization and display modules. And closed-loop automation of detection, analysis and demagnetization is realized. According to the method, a magnetic field sensor is not needed, the residual magnetism direction and size can be synchronously obtained in a high-precision and robust mode only through port electric signals, and the method is suitable for on-site off-line or live detection.

The invention discloses an energy consumption type pulse special power supply topology circuit, particularly relates to the technical field of power supply circuits, and is technically characterized in that a forward energy storage unit is used for outputting forward current to an external load coil and providing energy required by main compression for a field inversion configuration device; the negative energy storage unit is used for outputting negative current to an external load coil and providing bias field energy for the field inversion configuration device; the charging unit is also used for charging the current source unit; the current source unit is used for providing bias current for an external load coil and creating a bias condition for the field inversion configuration device; the resonance unit is used for outputting resonance current to an external load coil and providing energy required by pre-ionization for the field inversion configuration device; the first consumption unit is used for consuming residual electric energy after the external load coil and the current source unit work; the first control unit is used for controlling short circuit of the first consumption unit; the second control unit is used for controlling the on-off of the resonance unit; and the third control unit is used for controlling the on-off of the negative energy storage unit.

A non-isolated bidirectional high-voltage direct current battery charger is made compatible with a ground-fault circuit interrupter (GFCI) at the DC output by adapting the power converter to control, in response to voltage or current sensors, a net current difference between forward current and return current to remain below a threshold of the GFCI. This can be done without compromising safety in the case of actual ground faults.

The invention discloses a current injection type SiC MOSFET parallel current-sharing driving circuit, which detects the voltage difference between two ends of a current sampling resistor through an isolation amplifier and a differential amplification circuit, indirectly measures the current value of each parallel branch, and determines the current difference value of the parallel branches through the differential amplification circuit. And when the current of the SiC MOSFET parallel circuit is unbalanced, a control signal is output to the forward current injection circuit or the reverse current injection circuit. Through a forward current injection circuit and a reverse current injection circuit, forward current or reverse current is injected into a grid electrode under the action of a control signal, the change rate of grid-source voltage is changed, the switching-on and switching-off speed of SiC MOSFETs is dynamically adjusted, the phenomenon of non-uniform parallel current of the SiC MOSFETs caused by inconsistent device parameters or asymmetric circuit layout in the circuit is effectively inhibited, and the switching-on and switching-off speed of the SiC MOSFETs is improved. The active current sharing circuit has the advantages of being good in adjusting performance and high in response speed.

The invention provides a wide-range high-sensitivity passive rectifier. The wide-range high-sensitivity passive rectifier comprises a differential signal input end; the rectification circuit comprises a plurality of rectification NMOS tubes and a plurality of rectification PMOS tubes; substrates of the plurality of rectification PMOS tubes are connected with an output positive electrode of the rectifier, and substrates of the plurality of rectification NMOS tubes are connected with an output negative electrode of the rectifier; the feedback biasing circuit comprises a plurality of feedback PMOS (P-channel Metal Oxide Semiconductor) tubes and is used for adaptively controlling the highest grid voltage of the plurality of rectification NMOS (N-channel Metal Oxide Semiconductor) tubes; and the number of the plurality of rectification NMOS tubes is the same as that of the plurality of rectification PMOS tubes. The rectifier is based on the feedback bias circuit, the grid voltage of the rectification NMOS tube can be increased under low input power, forward current is expanded, and therefore sensitivity is improved; and meanwhile, the bias voltage is adaptively reduced under high input power, the grid voltage of the NMOS tube is clamped and rectified, the reverse current is effectively inhibited, and the wide dynamic range of the rectifier is expanded.

The invention relates to the technical field of backlight modules, and discloses a backlight module and a display device. A certain proportion of red dye is arranged in the optical component of the backlight module, the red light proportion in the backlight module is increased, and the red shift phenomenon of color points of the backlight module is actively caused; meanwhile, the proportion of red fluorescent powder and green fluorescent powder in the high-color-gamut LED is adjusted, the proportion of green light is properly increased, and visual effect screen body color point correction is achieved; the proportion of green fluorescent powder in the high-color-gamut LED is increased, so that the luminous efficiency of the LED can be improved, the thermal reliability can be improved, the upper limit value of driving forward current can be increased, and the high-color-gamut LED has advancement compared with a traditional white-light high-color-gamut LED; by means of the principle, scheme matching can be carried out according to requirements, the effect of improving the brightness of the backlight module is achieved, and an extreme cost design scheme is achieved.

The utility model relates to a uA-level positive and negative output constant current source circuit, which comprises a microcontroller, an H-bridge module, a DAC (Digital-to-Analog Converter) circuit and a current adjusting module, the microcontroller controls the H-bridge module, and the H-bridge module is connected with a load and outputs forward current or negative current to the load; the microcontroller controls the DAC circuit to output a DA value, and the DAC circuit is connected with the current adjusting module and used for controlling the stepping precision of the current output to the load. According to the utility model, on one hand, the flow direction of current passing through a load can be controlled through the H-bridge circuit, and positive and negative current output is realized; on the other hand, the stepping precision of the current passing through the load is controlled through the current adjusting module, and uA-level stepping current is achieved; compared with a common constant current source circuit, the constant current source circuit can better meet the electric control requirements of special loads such as a liquid lens.

A non-isolated bidirectional high-voltage direct current battery charger is made compatible with a ground-fault circuit interrupter (GFCI) at the DC output by adapting the power converter to control, in response to voltage or current sensors, a net current difference between forward current and return current to remain below a threshold of the GFCI. This can be done without compromising safety in the case of actual ground faults.

Back-surface roughness of a back surface of a silicon carbide semiconductor device having a MOS gate structure in a first region that is a region within 30 μm of a cross section (lateral surface) of the device is at most 4 μm while the back-surface roughness in a second region other than the first region is at most 2 μm, the back surface of the silicon carbide semiconductor device is the back surface of the second electrode. In a method of manufacture, the back-surface roughness of the device is specified to meet a predetermined condition. Then, ON voltages of the device before and after a forward current is passed through body diodes of the device are measured, and a rate of change of the ON voltage while the forward current is passed through body diodes is calculated, and then the device having a calculated rate of change less than 3% is identified.

The utility model provides a large-current trench gate field cut-off IGBT power device. The large-current trench gate field cut-off IGBT power device comprises a heavily doped first conductive type substrate; a heavily doped second conductive type collector region is arranged on the back surface of the first conductive type substrate, and collector metal is arranged on the back surface of the second conductive type collector region; a first conductive type buffer layer is arranged on the front surface of the first conductive type substrate; a lightly doped first conductive type epitaxial layer is arranged on the first conductive type buffer layer; a gate trench, a lightly doped second conductive type body region and a voltage dividing ring are arranged at the top in the first conductive type epitaxial layer; wherein the gate trench and the second conductive type body region are located in an active region of the device, and the voltage dividing ring is located in a terminal protection region of the device; the plurality of gate trenches are arranged in parallel, and two sides of the plurality of parallel gate trenches are respectively provided with a second conductive type body region; the number of the voltage dividing rings is at least one. The device has the advantages of high reverse breakdown voltage, high forward current capability and the like.

The invention discloses an energy feedback type pulse special power supply topology circuit, particularly relates to the technical field of power supply circuits, and is technically characterized in that a forward energy storage unit is used for outputting forward current to an external load coil and providing energy required by main compression for a field inversion configuration device; the current source unit is used for receiving and storing electric energy, providing bias current for an external load coil and creating bias conditions for the field inversion configuration device; the negative energy storage unit is used for outputting negative current to an external load coil and providing bias field energy for the field inversion configuration device; the charging unit is also used for charging the current source unit; the resonance unit is used for outputting resonance current to an external load coil and providing energy required by pre-ionization for the field inversion configuration device; the first bidirectional combination switch is used for controlling the on-off of the resonance unit; and the second bidirectional combination switch and the third bidirectional combination switch are used for controlling the positive on-off and negative on-off of the circuit.

The invention relates to the technical field of solar cells, in particular to a battery piece grading method. The battery piece grading method comprises the following steps: providing a photovoltaic module made of battery pieces at the same grade as to-be-graded battery pieces; obtaining a forward current of the photovoltaic module; according to the series resistance and the open-circuit voltage of the to-be-graded battery piece and the forward current of the photovoltaic module, the equivalent luminous power of the to-be-graded battery piece is obtained; and grading the to-be-graded battery pieces according to the equivalent luminous power of the to-be-graded battery pieces. According to the grading method of the battery pieces, the EL light and shade consistency of the photovoltaic module formed by the battery pieces which are graded by taking the equivalent luminous power of the battery pieces as the index is greatly improved.

A temperature sensor device is capable of measuring minute temperature changes while being manufactured at low cost without needing a high performance IC tester. A temperature sensor device includes a temperature sensor circuit 2 and a temperature sensor 1. The temperature sensor 1 includes a PN junction element 15 which is a temperature sensing element, a variable current source which supplies different forward currents of at least two values to the PN junction element 15 and a constant voltage source 16 which outputs a constant voltage having the same temperature properties as a forward voltage of the PN junction element 15.

The invention relates to the technical field of measurement of long-distance and high-accuracy temperature measurement resistors, and particularly discloses a resistor temperature measurement method, which comprises a constant current source I, temperature measurement resistors RX and RY, a reference resistor RR, an analog switch, an instrument amplifier, an analog-to-digital converter and a microcontroller, the method comprises the following specific steps that S1, an analog switch controls a constant current source I to sequentially flow through temperature measurement resistors RX and RY and a reference resistor RR, and current generates a voltage on each resistor and is in direct proportion to the resistance value of the voltage; and S2, measuring the voltages of the temperature measuring resistors RX and RY and the reference resistor RR through an instrument amplifier and an analog-to-digital converter to obtain VX1, the voltage of the temperature measuring resistor RX under the forward current condition, VY1, the voltage of the temperature measuring resistor RY under the forward current condition, and VR1, the voltage of the temperature measuring resistor RR under the forward current condition. According to the resistance temperature measurement method, 0.00025 DEG C or better uncertainty can be obtained, and observable errors caused by thermoelectromotive force can be effectively eliminated.

The invention discloses a low-cost all-vertical gallium nitride Schottky barrier diode and a preparation method thereof. The diode comprises a transmission layer; the drift layer is located on the lower surface of the transmission layer; the positive electrode is located in the middle of the lower surface of the drift layer; the negative electrode is located in the middle of the transmission layer; the first dielectric layer is located on the lower surface of the remaining drift layer and the side wall and part of the lower surface of the positive electrode; the second dielectric layer is located on the upper surface of the remaining transmission layer and the side wall and part of the upper surface of the negative electrode; the positive electrode thickening layer is located on the lower surface of the first dielectric layer and the lower surfaces of the remaining negative electrodes; the conductive substrate is positioned on the lower surface of the positive electrode thickening layer; the additional positive electrode is positioned in the middle of the lower surface of the conductive substrate; the negative electrode thickening layer is located on the upper surface of a part of the second dielectric layer and the upper surface of the remaining negative electrode. According to the invention, a completely longitudinal conductive vertical device structure is realized, the forward current density of the device is improved, and the on-resistance is reduced.

The application discloses a relay, and belongs to the technical field of electric appliance switches. The relay comprises a first shell, an electromagnetic structure, a moving contact structure and a stationary contact. The electromagnetic structure and the stationary contact are both fixed in the first shell. The electromagnetic structure is provided with two first magnetic parts which are spaced apart along a first direction. The moving contact structure is slidably arranged in the first shell along a second direction. The moving contact structure comprises a moving contact, a first moving magnetic part and a second moving magnetic part which are sequentially and spaced apart along the second direction. The magnetic poles of the first moving magnetic part and the second moving magnetic part are opposite. When a forward current is input into the electromagnetic structure, the two first magnetic parts are both attracted to the first moving magnetic part, and the moving contact and the stationary contact are separated. When a reverse current is input into the electromagnetic structure, the two first magnetic parts are both attracted to the second moving magnetic part, and the moving contact and the stationary contact are in contact. The relay provided by the application is beneficial to increasing the opening distance between the moving contact and the stationary contact, and reducing the risk of electric leakage from the moving contact and the stationary contact to the electromagnetic structure.

The invention provides a semiconductor structure which comprises a substrate and a multi-channel heterojunction layer which are arranged in a stacked mode, the multi-channel heterojunction layer comprises a plurality of heterojunction layers, each heterojunction layer comprises a channel layer and a barrier layer, and the multi-channel heterojunction layer is provided with a plurality of grooves; and the P-type epitaxial layer comprises a plurality of first P-type regions for filling the grooves. The transverse PN junction is formed through the first P-type region and the two-dimensional electron gas in the heterojunction, the depletion region of the PN junction is broadened during reverse biasing so as to pinch off a current channel, the Schottky junction with low barrier height is effectively shielded, the Schottky barrier lowering effect can be inhibited, reverse leakage current can be controlled, and therefore the breakdown voltage is improved, and the low turn-on voltage is kept. And meanwhile, a plurality of parallel two-dimensional electron gas passages are formed between the cathode and the anode by utilizing stacking of a plurality of heterojunctions, so that depletion of two-dimensional electron gas by the first P-type region is compensated, and the forward current of the diode is ensured.

The utility model relates to the technical field of medical equipment, and particularly discloses a bipolar nanosecond pulse synchronous output circuit and ablation equipment, which comprise a positive pulse output circuit and a negative pulse output circuit, the positive pulse output circuit comprises a positive pulse charging unit, a positive pulse output control unit, a positive pulse transmission unit and a positive pulse output electrode wire which are electrically connected in sequence; the negative pulse output circuit comprises a negative pulse charging unit, a negative pulse output control unit, a negative pulse transmission unit and a negative pulse output electrode wire which are electrically connected in sequence; the positive pulse transmission unit at least comprises a forward multiplication transmission unit which is used for performing forward voltage multiplication or forward current multiplication on the forward output pulse signal; the negative pulse transmission unit at least comprises a negative multiplication transmission unit which is used for carrying out negative voltage multiplication or negative current multiplication on the negative output pulse signal. The bipolar nanosecond pulse synchronous output circuit provided by the utility model can improve instant pulse energy of nanosecond pulse tumor ablation equipment.

The invention relates to the technical field of solar photovoltaic modules, and particularly discloses a process method for passivating and contacting an auxiliary battery at a module end. The process method comprises the following steps: after battery pieces are subjected to series welding, lamination and packaging to form a battery assembly, the battery assembly is placed in an environment box for illumination, the temperature is set to be 50-75 DEG C, the irradiance is 1000-1500 Wh / m < 2 >, the forward current is 2-5 A, and illumination is carried out for 1-4 h. Under the conditions of high irradiance, medium temperature and low current, the battery piece adopting the LECO technology has a good internal defect repairing effect, contact between a metal electrode and silicon can be optimized again, the FF value and the Voc value of the battery assembly are improved, and therefore the power of the battery assembly is remarkably increased; and the contact resistance and passivation effect can be optimized at the component end in an auxiliary manner, so that the component power is improved, novel equipment does not need to be added on a production line, and the production efficiency is not influenced.

A moving core has a moving core main member made of soft magnetic materials and a permanent magnet member made of hard magnetic materials. A direction of the magnetic pole of the permanent magnet member matches that of a coil when the coil is positively energized with the forward current, and a stator core is non-existent in a range of movement of the permanent magnet member. Since there is the non-existent portion of the stator core in the range of movement of the permanent magnet member, it is possible to prevent generation of a magnetic flux loop of the magnetic field of the permanent magnet and it is possible to prevent a reduction of the attractive force.

The present application relates to the field of device fault diagnosis, and provides a device fault diagnosis method, system and equipment based on phase current and zero sequence voltage, comprising calculating phase current steady-state value and phase current fault transient value, and constructing single-phase open circuit fault flag; when the single-phase open circuit fault flag indicates that there is single-phase open circuit fault, obtaining fault phase flag quantity through phase current intensity coefficient; constructing first inverter fault flag through zero sequence voltage, when the first inverter fault flag indicates that there is fault, constructing second inverter fault flag through phase current unit value, obtaining inverter fault flag through the first inverter fault flag and the second inverter fault flag, determining device positioning threshold, constructing inverter fault positioning flag based on the device positioning threshold, positive current intensity and negative current intensity; obtaining final fault positioning flag, thereby diagnosing device fault of the device.

The present invention relates to a PN junction base-coupled gallium nitride Schottky diode and a preparation method thereof. The Schottky diode comprises a substrate layer, an epitaxial layer, an ohmic electrode, an anode and a cathode, wherein the epitaxial layer is located on the substrate layer, the epitaxial layer comprises a buffer layer, a contact layer, a drift layer and a regrown barrier layer, the buffer layer, the contact layer and the drift layer are stacked in sequence, the regrown barrier layer is arranged on the side and part of the upper surface of the drift layer, a PN junction is formed between the regrown barrier layer and the drift layer; the ohmic electrode is located on the regrown barrier layer; the anode is located on the drift layer and the regrown barrier layer and covers the ohmic electrode; the cathode is located on the contact layer. A PN junction is formed between the regrown barrier layer and the drift layer in the Schottky diode, which can deplete the sidewall electrons in the N-type material, play a role in modulating the electric field, reduce the edge electric field strength of the Schottky metal deposition, improve the breakdown voltage and reverse breakdown voltage, and has little effect on the forward characteristics, and has a higher forward current.

The application discloses a three-phase voltage source inverter, which comprises: inverter A, B and C three-phase upper and lower working bridge arms V a1 、 b1 、 c1 、 a2 、 b2 、 c2 , corresponding anti-association diodes VD a1 、 b1 、 c1 、 a2 、 b2 、 c2 , upper and lower bridge arm shunt switch devices S1 and S2, three-phase selective switch devices T a1 、 b1 、 c1 、 a2 、 b2 、 c2 in additional dynamic shunt branches; when the inverter AC side three-phase current has a phase with a maximum positive current, the T a2 、 b2 、 c2 corresponding to the additional dynamic shunt branch are turned on, and the S1 of the additional dynamic shunt branch is shunted in parallel to the phase with the maximum positive current; when a phase with a maximum reverse current exists, the T a1 、 b1 、 c1 corresponding to the additional dynamic shunt branch are turned on, and the S1 of the additional dynamic shunt branch is shunted in parallel to the phase with the maximum reverse current. The application reduces the overcurrent of the inverter working bridge arm switch device caused by AC system disturbance, and improves the operation reliability of the inverter.