690 results about "Power diode" patented technology

The invention relates to a vehicle-mounted fuel cell and storage cell directly paralleled power system with a super capacitor. The power system comprises a fuel cell galvanic pile, a fuel cell accessory system, a fuel cell controller, a storage battery group, a super capacitor group, a high voltage bidirectional DC / DC (direct current) converter, a small power unidirectional DC / DC converter, a motor controller, a driving motor and a system energy management controller, wherein a high voltage output end of the fuel cell galvanic pile is connected with an anode of a power diode through a high voltage switch K1, and the high voltage output end of the storage battery group is directly connected with a cathode of the power diode and the high voltage output end of the motor controller in parallel through a high voltage switch K2 to form a direct current bus. The super capacitor group is connected with the direct current bus through the high voltage bidirectional DC / DC converter, and the high voltage output end of the storage battery group is connected with the fuel cell accessory system through the small power unidirectional DC / DC converter. According to the system disclosed by the invention, a power supply mode in which galvanic pile output needs large power DC / DC voltage stabilization of a conventional fuel cell is abandoned, and the efficiency is improved; the instantaneous needed power of the direct current bus can be compensated by the arranged super capacitor group, the bus voltage is steadied, and braking energy can be quickly and effectively recycled.

this invention relates to power in direct-current circuits. The invention takes gallium arsenide as foundation (1). On the foundation has power divider, power synthesizer, 90deg phaser, solid beam structure. Power divider and power synthesizer composed by port one (7), port two(8), port three(8), dissymmetry coplane band line(10), nitride tantalum electric resistance. Solid beam structure includes signal input port(16), pier(5), solid beam(13), pedestal structure(6), sensing electrode(4), sensing electrode leader(12), capacitance detecting port(15), air bridge(14). There are nitriding silicon medium layer on the transmission line, pedestal structure and sensing electrode under solid beam, and sensing electrode leader under Air Bridge.

The fuel cell vehicle mixed power system using super capacitor as auxiliary power device belongs to the field of fuel cell vehicle technology. The galvanic pile of fuel cell system is connected with motor controller by means of forward direction of power diode: the super capacitor is connected with cathode of power diode by means of bidirectional main DC / DC converter; the low-voltage end of bidirectional 24V DC / DC converter is connected with 24V battery, its high-voltage end is connected with cathode of power diode; the motor controller, bidirectional main DC / DC converter, super capacitor management system, bidirectional 24V DC / DC converter, fuel cell controller and whole vehicle controller are electrically connected; and the fuel cell controller, bidirectional main DC / DC converter, bidirectional 24V DC / DC converter, motor controller and super capacitor management system are connected with whole vehicle controller by means of CAN network.

Double clad large mode area planar lasers or amplifiers comprising rare-earth or transition metal doped planar core regions are used to generate near-diffraction-limited optical beams of ultra-high power. The amplified light is guided in the core using different guiding mechanisms in two orthogonal axes inside the core. Waveguiding along a first long core axis is obtained substantially by gain-guiding or thermal lensing. Waveguiding along a second short core axis is obtained by index guiding. This is accomplished by surrounding the planar core region with regions of different refractive index. The long sides of the planar core region are surrounded with a depressed refractive index cladding region. The short sides of the planar core region are surrounded with a cladding region substantially index-matched to the core region. The whole structure is surrounded by an outer cladding region with a low refractive index to enable cladding pumping of the planar waveguide with high-power diode lasers. The rare-earth or transition metal doping level inside the planar core can be constant and can also vary substantially without negatively affecting the waveguiding properties. To avoid bend losses along the long axis of the planar waveguide, the planar core region and the planar waveguide are aligned parallel to each other and the planar waveguide is coiled with the long side of the planar waveguide mounted to a drum. The drum can also be used as a heat sink. A planar waveguide comprising a planar core region can be manufactured using conventional fiber fabrication methods.

A power diode having a silicon mesa atop the drift region includes a first contact positioned on the silicon mesa. The silicon mesa is highly doped p-type or n-type, and the anode may be formed on the mesa. The mesa may include two separate silicon layers, one of which is a Schottky barrier height layer. Under a forward bias, the silicon mesa provides carriers to achieve desirable forward current characteristics. The substrate has a significantly reduced thickness. The diode achieves reverse voltage blocking capability by implanting junction barrier Schottky wells within the body of the diode. The diode utilizes a deeper portion of the drift region to support the reverse bias. The method of forming the diode with a silicon mesa includes forming the mesa within a window on the diode or by thermally or mechanically bonding the silicon layer to the drift region.

The invention discloses a high power laser diode comprising a plurality of laser light emitters (2) and a plurality of light collimating means (33), wherein each of the laser light emitters (2) defines, in a direction perpendicular to a direction of propagation (32) of an output laser beam, a fast axis (y) and a slow axis (x), and wherein each of the light collimating means is associated with a laser light emitter and configured for collimating the output laser beam at least in a fast axis (y) direction. In order to enable a simple and cost-efficient assembly of the diode laser with collimating means, having a layered structure consisting of a plurality of plane-parallel substrates. For this purpose, the diode laser comprises planar substrate means (10, 30) which serves to precisely define a distance between a respective laser light emitter (2) and an associated light collimating means to the order of one or several millimetres and to support the collimating means (33) such that the optical axis of said laser light emitters are parallel to each other and for defining a precise location of emitters on the planar substrate (10), preferably at predetermined distance in fast axis direction between said laser light emitters. The collimating means is an array or multiple single of micro-optical lenses having a rear side which is bonded to the upper surface of the planar spacer means. The submounts of the light emitters (2) are mounted to the planar substrate means (10, 30) and to a heatsink (6).

Laser for thermal shrinkage of soft tissue of uvula, soft palate, nasal turbinate or tongue base for the treatment of snoring, nasal obstruction or sleep apnea are disclosed. The preferred laser includes infrared laser about 0.7 to 1.85 micron, pulse duration about 100 microsecond to 5 seconds, spot size of about 2 to 5 mm and power of about 2 to 20 W at the treated area. The laser energy is delivered to the treated area by an optical fiber and a hand piece to cause a localized temperature about 65 to 85 degree Celsius for sufficient shrinkage of the treated soft tissues. Optical fiber bundles to produce high-power diode laser output or multi-wavelength are also disclosed.

A self-oscillation type resonant flyback converter includes a series combination of a primary winding and a switching transistor. A secondary winding is connected to a power diode and to an output capacitor. A feedback winding is connected to a delay driving circuit comprising a delay diode, a constant-current diode and a capacitor. The delay driving circuit is provided to delay a positive feedback signal from said feedback winding, so that when said power diode becomes non-conducting, said delay diode becomes in the reverse conduction state, starting a free resonance period that concludes when the said delay diode becomes non-conducting and the switching transistor is achieved at zero voltage switching.

Methods and constructions for cryogenically cooled solid state lasers are provided that allow the cooling channels to be embedded within the buffer heat sinks used to conductively cool the laser medium. Several gain medium geometries are disclosed that are compatible with efficient and straight forward cryogenic cooling techniques using practical pump chamber designs while eliminating the need for the pump light to traverse the cryogenic layers and allowing for smooth temperature cycling. A number of active material configurations that can be generally adapted for pumping by high power diodes, including slab, thin disk, active mirror, and rod geometries, are shown to be compatible with the cryogenic cooling approaches. Modeling results based on the preferred cooling configurations indicate substantial improvement in the performance of common solid state lasers, including Nd- and Yb-doped lasers. These improvements have been realized in a multiple thin-disk Yb:YAG folded resonator configuration.

Array comprising high power laser diode comprising laser light emitters, each defining, in a direction perpendicular to direction of propagation of an output laser beam, a fast axis and a slow axis; fast axis collimating means for collimating output laser beams in fast axis direction; and slow axis beam shaping means for collimating or focussing output laser beams in slow axis direction, said slow axis beam shaping means disposed external to said high power laser diode; wherein said laser light emitters are displaced relative to each other in fast axis direction or in fast and slow axis direction by equidistant spacings, respectively; and including optical means for forming output laser beam profile in far field of all laser light emitters consisting of said fast and slow axis collimated or focussed output laser beams arranged adjacently in seamless manner in one or two dimensions with optical fill factor of about 100%.

An object is to provide a semiconductor device having electrical characteristics such as high withstand voltage, low reverse saturation current, and high on-state current. In particular, an object is to provide a power diode and a rectifier which include non-linear elements. An embodiment of the present invention is a semiconductor device including a first electrode, a gate insulating layer covering the first electrode, an oxide semiconductor layer in contact with the gate insulating layer and overlapping with the first electrode, a pair of second electrodes covering end portions of the oxide semiconductor layer, an insulating layer covering the pair of second electrodes and the oxide semiconductor layer, and a third electrode in contact with the insulating layer and between the pair of second electrodes. The pair of second electrodes are in contact with end surfaces of the oxide semiconductor layer.

Array comprising high power laser diode comprising laser light emitters, each defining, in a direction perpendicular to direction of propagation of an output laser beam, a fast axis and a slow axis; fast axis collimating means for collimating output laser beams in fast axis direction; and slow axis beam shaping means for collimating or focussing output laser beams in slow axis direction, said slow axis beam shaping means disposed external to said high power laser diode; wherein said laser light emitters are displaced relative to each other in fast axis direction or in fast and slow axis direction by equidistant spacings, respectively; and including optical means for forming output laser beam profile in far field of all laser light emitters consisting of said fast and slow axis collimated or focussed output laser beams arranged adjacently in seamless manner in one or two dimensions with optical fill factor of about 100%.

The invention discloses a split induction three-level photovoltaic grid-connected inverter and a control method thereof and belongs to the technical field of a power electric transformer. The inverter comprises a power supply circuit (A), a first converting branch (B) and a second converting branch (C), wherein the power supply circuit (A) consists of a direct current power supply and two voltage-dividing capacitors; the first converting branch (B) and the second converting branch (C) respectively consist of a power diode, a split inductance and two power switching tubes. The inverter can be expanded into a three-phase circuit structure according to the capacitance requirement and has the same principle with the single-phase structure. The control method of the inverter comprises two parts which respectively are the hysteresis ring width frequency-fixing control of the inverter side inductance current and the early closing of the high-frequency switch driving signal. The invention does not generate high-frequency leakage current when working in the single-polar PWM modulation mode, and does not have the bridge arm direct-connection danger, and the voltage stress of the power switching tubes and the diode are respectively equal to or smaller than one half of the input voltage.

The invention discloses a capacitor-clamped three-level dual-buck half-bridge inverter which comprises a first three-level duck circuit, a second three-level duck circuit, a direct-current power-supply input circuit and a load circuit, wherein each three-level duck circuit comprises two power switching tubes, two power diodes, a clamping capacitor and an inductor, and +1, -1 and 0 three-state levels are output by an inverter bridge under the actions of controlling the switching tubes and clamping the clamping capacitor, thereby realizing the three-level dual-buck half-bridge inverter. The invention has the advantages that the advantage that a DBI circuit has not problems of through bridge arms or backward recovery of switching tube body diodes is inherited; the advantage that a three-level convertor per se has small output voltage harmonic content is reserved; compared with a traditional half-bridge inverter, the voltage stress of power devices is reduced; and the whole circuit structure is simpler and easy to realize.

The invention provides a high-gain Z-source inverter, comprising a three-phase inverter, which is composed of a direct-current voltage source and a three-phase inversion bridge. The high-gain Z-source inverter further comprises a Z-source network, which is composed of a power diode, a switch inductor and a capacitor. The high-gain Z-source inverter is characterized in that a single inductor is replaced by a branch circuit of the switch inductor; the head end of the Z-source network is connected with the positive electrode of a power supply; the tail end of the Z-source network is connected to the positive end of the three-phase inversion bridge; and the inversion bridge and the power supply are grounded commonly. Compared with the traditional Z-source inverter, the Z-source inverter disclosed by the invention is capable of improving the boost capacity of the inverter, realizing a high modulation factor and improving the output quality of the whole inverter; and simultaneously, the voltage stress of the Z-network capacitor can be effectively reduced so as to reduce the volume and the weight of the inverter.

The invention discloses a fuel battery automobile mixing power system, which comprises the fuel-battery sub-system, the accumulator branch system, the power diode, the bidirectional DC / DC converter, the 24VDC / DC converter and the electric machine controller. The fuel battery connects to the electric machine controller through the power diode linking to the bidirectional DC / DC converter, the accumulator group paralleled connects in front of the electric machine controller, and the input terminals of the bidirectional DC / DC converter paralleling connect the assistant equipment of the fuel battery and the 24VDC / DC converter. At the beginning of the startup of the whole system, the fuel battery system will not start immediately, and the accumulator system provides the power for the system, and when the fuel battery system is started and works normally it provides the power for the whole power system. The invention reduces the power volume of DC / DC converter and the design size, improves the reliability of the operation of the whole power system and the efficiency of the system running.

The invention relates to a double-boost energy-feedback PWM rectifier circuit, which can work in an AC / DC rectification or DC / AC active inverter energy-feedback mode. It is composed of input power supply, two step-up bridge arm circuit units, output filter capacitor and load circuit. The first boost type bridge arm circuit unit is composed of a power switch tube, a power diode and a boost inductor; the second boost type bridge arm circuit unit is composed of a power switch tube, a freewheeling diode and a boost inductor; the output filter capacitor and load The circuit consists of two capacitors and a load. The two step-up bridge arm circuit units work in turn for half a power grid cycle, and the control circuit can select the corresponding step-up bridge arm circuit unit to work according to the positive and negative half cycle judgment of the input current. The energy of this circuit can flow bidirectionally, there is no bridge arm through problem, and the work reliability is high; only one power tube is chopped at high frequency in each switching cycle, and the loss is small. The rectification circuit has good application prospects in UPS, aerospace and other occasions.

The invention discloses a resonance type DC solid circuit breaker which belongs to a solid circuit breaker and comprises a DC power supply, a main switching unit A, an auxiliary switching unit B and a load, wherein the main switching unit A comprises a main switching thyristor and a main switching power diode; the auxiliary switching unit B comprises a first thyristor, a second thyristor, a third thyristor, a fourth thyristor, a first inductor, a second inductor, an energy-storing impulse capacitor and an auxiliary switching power diode. The invention improves the capacity of the breaker, lowers the cost, realizes the soft starting (shutoff) of a solid switch, and improves the reliability of the breaker.

The invention discloses an on-line detection system and method for the work junction temperature of a power diode module. According to the on-line detection system and method, on-off of an active switch device is controlled to enable the power diode module to be switched in the turn-on state and the turn-off state. When the power diode module is switched to be turned off from being turned on, currents flowing through the power diode module are converted to a complementary switch tube, the reverse recovery currents of the power diode module can generate corresponding induced voltages on a stray inductor of a conversion circuit, and the induced voltages are related to the reverse recovery currents of the power diode module and also comprise the temperature information of the power diode module. According to the on-line detection system and method for the work junction temperature of the power diode module, the variation condition of the reverse recovery currents comprising the temperature information can be measured on the complementary switch tube only by one low-voltage amplitude detection circuit, and additional high-voltage passive auxiliary elements are of no need. While a driving circuit sends control signals, variation voltages caused by the reverse recovery currents are captured, and high precision and real-time performance are achieved.

The present invention discloses a super audio square wave DC pulse power supply equipment used for electric arc welding, which mainly comprises a rectification filter circuit, a peak value current producing circuit, a pulse peak value current switching circuit and a background value current producing circuit. The background value current producing circuit is used for producing the background value current Ib, and is effected on the cathode end of the power diode DP, and the peak value current producing circuit is used for producing the peak value current Ip which outputs the pulse peak value current Ipp through a fifth power switch tube TP and the power diode DP, and then the background value current Ib and the pulse peak value current Ipp are piled, thereby getting the pulse current IF to supply the electrode and workpiece. The super audio square wave DC pulse power supply equipment of the present invention can realize the pulse current frequency not less than 20 kHz, and the pulse current amplitude value is 1 to 300 A, and the ascension rate of the pulse current is not less than 50 A / Mus.

The invention relates to a three-voltage dual-reduction full-bridge inverter, wherein it comprises power circuit (1), two reduction circuits (2, 3), filter capacitors and load circuit (4), and work-frequency switch circuit (5); the inputs of circuits (2, 3) are connected to circuit (1), while outputs are connected to filter capacitor and load circuit (4). The invention is characterized in that: the ground part of filter capacitor (Cf) via two switch tubes is connected to the anode and the cathode of bus voltage; the external bus voltage is reduced from 2Ud to Ud. The invention has simple structure and control method.

The invention discloses a plastic-encapsulated power diode and a manufacturing process thereof, and relates to the technical field of semiconductor discrete devices. Its manufacturing process does not adopt the cleaning and dehydration process of organic solvents such as isopropanol and absolute ethanol in the prior art, and the water washing and dehydration process after cleaning with organic solvents is omitted; the chip connected with the wire is put into a heated oven Baking in medium temperature for 4-10 hours, the oven temperature is 200-250°C, and the hydrogen-nitrogen mixed gas or clean air is passed through the oven; put the chip coated with liquid epoxy resin or liquid silicone rubber into the oven at 150±10°C to cure the glue for 10 -60 minutes. Compared with the prior art, the product of the invention has excellent high-temperature characteristics, consistency and reliability.

The invention discloses a thick-film magnetic isolation direct current solid-state power controller which comprises a power MOSFET (metal oxide semiconductor field effect transistor), a detection resistor, a power diode, a TVS (transient voltage suppressor) diode, a current conditioning circuit, a voltage detection circuit, a voltage state judgment circuit, a current state judgment circuit, an immediate trip circuit, an inverse time circuit, a short-circuit detection circuit, a driving circuit, a state synthetic circuit, a trip state latch circuit, a time delay reset circuit, a time sequence matching circuit, a DC / DC (direct current / direct current) isolated power supply, a first isolation circuit, a second isolation circuit, a third isolation circuit, a state feedback interface circuit, a control signal interface circuit and a power-on reset circuit. The circuit structure can optimize the electrical properties of the controller, reduce the volume and the weight, improve the reliability and is widely applied to civil low-voltage direct current power distribution systems, aviation, aerospace, tanks, automobiles, ships and other fields.

The invention discloses a power diode module working junction temperature on-line detection system and detection method. By controlling the connection and disconnection of an active switch device, a power diode module is allowed to be switched between an on state and an off state; and when the power diode module is switched from the on state to the off state, the current passing through the power diode module commutates to a complementary switch tube, and the reverse recovery current of the power diode module generates corresponding induced voltage in a stray inductor of a commutation loop, wherein the induced voltage is related to the reverse recovery current of the power diode module and meanwhile, comprises temperature information of the power diode module. The change information of the reverse recovery current comprising the temperature information can be measured in the complementary switch tube by utilizing a low-voltage amplitude detection circuit without extra high-voltage passive auxiliary components; while a drive circuit sends a control signal, change voltage caused by the reverse recovery current is captured; and the detection method and system have higher precision and real-time performance.

The invention relates to a neutral point potential balancing control system and method of a three-level inverter. The neutral point potential balancing control system and method are used for conducting effective balancing control over the neutral point potential of the high-power diode clamped three-level inverter and collecting the DC bus voltage of the three-level inverter and the neutral point voltage value of two capacitors on the DC side in real time, sending collected signals to two independent PI regulators to generate corresponding controlled quantities, determining the operating mode of the system and the corresponding on-off state of switching tubes according to the obtained controlled quantities, determining the neutral point potential by the way of meeting the requirement of the turn-off time ratio of switching devices at the same time, determining the constraint condition of a busbar voltage according to the sum of connecting time, and accordingly adjusting the duty ratio of two switching tubes in an improved three-level DC / DC module, and therefore the busbar voltage on the DC side is controlled so that the dynamic voltage-sharing process of two supporting capacitors on the DC side can be achieved. Fluctuation of the neutral point potential of the three-level inverter is effectively reduced or restrained ultimately, system performance is improved, and the responsiveness of the system and the stability of a three-level topology circuit are improved.

With a non-linear element (e.g., a diode) with small reverse saturation current, a power diode or rectifier is provided. A non-linear element includes a first electrode provided over a substrate, an oxide semiconductor film provided on and in contact with the first electrode and having a concentration of hydrogen of 5×1019 atoms / cm3 or less, a second electrode provided on and in contact with the oxide semiconductor film, a gate insulating film covering the first electrode, the oxide semiconductor film, and the second electrode, and third electrodes provided in contact with the gate insulating film and facing each other with the first electrode, the oxide semiconductor film, and the second electrode interposed therebetween or a third electrode provided in contact with the gate insulating film and surrounding the second electrode. The third electrodes are connected to the first electrode or the second electrode. With the non-linear element, a power diode or a rectifier is formed.

The invention discloses a diode clamping five-level dual buck half-bridge inverter which comprises a first five-level buck circuit, a second five-level buck circuit, a direct current power input circuit and a load circuit. The inverter is controlled by adopting voltage-current dual closed loop SPWM (Sinusoidal Pulse Width Modulation), the two five-level buck circuits are controlled to work withina half cycle according to the direction of inductive current and the magnitude of output voltage, and five-level PWM (Pulse-Width Modulation) wave output is obtained respectively on two output bridgearms through different switch combination. The invention has the advantages that the advantages of straight through without bridge arms of the dual buck circuits and diode reverse recovery without switching tube are reserved; five-level output is realized, and the harmonic wave content of output voltage is reduced, thus the size of a filter can be reduced, the switching frequency of a PWM part can be reduced, the switching loss can be reduced, and the efficiency can be improved; compared with a half-bridge type inverter, the voltage stress of power devices is reduced so that a switching device of medium or low power is suitable for occasions of high voltage and high power; and only eight power diodes are needed in the circuits, compared with a five-level diode clamping inverter, the quantity of the diodes is reduced by 1 / 3, and a clamping circuit is simplified.

The invention discloses an alternative-current / direct-current (AC / DC) dual-purpose motor control system, which is characterized in that: an electric power electronic part Insulated Gate Bipolar Transistor (IGBT) is adopted as a non-contact controllable switch to form a control main circuit, a digital microprocessor is adopted as a control core to form a micro-controller-based AC / DC dual-purpose motor control system. The control main circuit firstly adopts four power diodes to form a single-phase full-wave rectifier bridge, so an external AC power supply system and an external DC power supply system are unified to an internal DC power supply. An AC / DC dual-purpose motor control topology main circuit is arranged behind the rectifier bridge. The IGBT in the control topology main circuit is connected and disconnected according to a given discipline, so the connection order of different homonymous ends of a motor exciting winding and an armature winding can be realized, and the motor can run in the positive direction and the opposite direction or can be braked in the positive direction and the opposite direction. Due to the adoption of the AC / DC dual-purpose motor control system, the service life of the system is greatly improved, the electric arc and spark of the switch can be eliminated, the size can be reduced, and complicated functions of an AC / DC dual-purpose such as soft starting, stepless speed regulation and the like can be realized. The invention also provides a full-digital communication field bus interface so as to realize the remote monitoring of a field bus.

The invention relates to a compound auxiliary winding TiBuck-Flyback single-stage LED driving circuit which comprises an input power supply uin, a rectifier bridge BD1, a transformer Tr, a power metal oxide semiconductor (MOS) switching tube S1, a power MOS switching tube S2, a power diode D1, a power diode D2, a power diode D3, a power diode D4, an electrolytic capacitor Cs1, an electrolytic capacitor Cs2, an electrolytic capacitor Cs3, an output capacitor Co2, an output inductor Lo and an output load LED. By construction of the single-stage auxiliary TiBuck-Flyback compound LED driving circuit and a self-adaption control circuit thereof, functions such as efficient, low-ripple and constant current output are achieved.

The invention discloses a double-Cuk buck-boost output parallel-type converter which is formed by connecting two Cuk-type DC / DC (direct current / direct current) converters capable of achieving the buck-boost output at the output in parallel, and can achieve the DC / AC (direct current / alternating current) single-phase conversion and further achieve the three-phase conversion through expansion. The converter has the following basic functions: the double-Cuk buck-boost output parallel-type converter can achieve the buck-boost conversion and normally serve the function of conversion even if the inputted DC voltage is lower or the variation range of the DC voltage is wider; the problem that the bridge arms are directly connected is avoided in the entire circuit, thus ensuring the high reliability; the follow current is not allowed to pass through the body diode of a switching tube, but flows through an independent diode, so that a power switching tube and a power diode can be respectively subject to optimized design; the design of circuit parameters, which is based on the method for designing a DC Cuk converter, is simple; and the inductive current runs in a continuous state, thus reducing the EMI (electro-magnetic interference). The invention is mainly applicable to the fields of photovoltaic generation, fuel-cell power generation and other power generation based on renewable energy and new energy, in which the level of operating voltage is lower or the variation range thereof is wider.