54results about How to "Reduce the voltage rating" patented technology

In an AC link type boosting device, DC terminals of two voltage inverters are connected each other in series in additive polarity and plural AC terminals of each of the voltage inverters are connected to a transformer. The two voltage type inverters are AC linked to each other via the transformer. An external voltage applied between the DC terminals of the AC link type booster is divided by the voltage-type inverters.

The invention discloses a parallel combined converter with multi-module input and serial output as well as a soft start control method thereof, belonging to the field of converter control. A circuit of the converter is formed by adding a current peak value suppression and input voltage-sharing control circuit and a switching pipe drive circuit on the basis of an original combined converter; the sampling voltage of output current is compared with a threshold value of a hysteresis comparator determined by given reference voltage and output to a logical OR-gate through a phase inverter; an inputvoltage sampling value is compared with a threshold level determined by the given reference voltage and then output to the logical OR-gate; when the output of the logical OR-gate is a high level, theswitching pipe is controlled to discharge a soft start capacitor of a drive chip so as to stop outputting drive signals and turn off modules; when the output of the logical OR-gate is a low level, theswitching pipe is controlled to be closed, and the soft start capacitor of the drive chip is charged so as to generate the drive signals and turn on the modules. The invention realizes current peak limiting and module input voltage-sharing, improves the reliability of the converter and reduces the cost.

The present invention relates to a solid state lighting system comprising at least one light emitting semiconductor device (LEDstr), at least one driving means (LEDdr) for driving a predetermined current through the at least one light emitting semiconductor device (LEDstr). The lighting system furthermore comprises a first voltage supplying unit (PS1) coupled to provide a first supply voltage (Vbus1) to a first side of the at least one light emitting semiconductor device, and a second voltage supplying unit (PS2) coupled to provide a second supply voltage (Vbus2) for the at least one light emitting semiconductor device. The first and the second supply voltages (Vbus1, Vbus2) are selected to optimize the voltage drop across the at least one light emitting semiconductor device (LEDstr).

A 3-phase uninterruptible power supply (UPS) including first, second, and third AC / DC converters, a DC / DC converter, and at least one DC / AC converter coupled to multiple electrical buses. The first, second, and third AC / DC converters each being configured to receive AC power and to provide multiple DC signals to the multiple electrical buses. The DC / DC converter being configured to convert DC voltages present on the multiple electrical buses to a DC voltage that can be used to charge a battery. The DC / AC converter being configured to receive DC power from the multiple electrical buses and to provide an AC output. The 3-phase UPS being configured such that when suitable AC power is provided to the AC / DC converters, the DC / DC converter is configured to charge a battery, and when suitable AC power is not provided to the AC / DC converters, the DC / DC converter is configured to provide DC power to the multiple electrical buses using power provided by the battery.

The invention discloses a multi-power-source rail vehicle and a main and auxiliary transmission system and method thereof. The multi-power-source rail vehicle comprises a power supply system, an intermediate direct-current link, a traction inverter, a traction motor and an auxiliary system which are sequentially connected, and the power supply system comprises a diesel generator power supply system, a power grid power supply system and a power battery power supply system; and the auxiliary system is connected to the power battery power supply system. The auxiliary system takes power from the power battery power supply system. The invention breaks through the inherent operation modes of internal combustion and electric locomotives. When the railway vehicle runs on an electrified line, the locomotive can be powered by a contact power grid; and when running on a non-electrified line, the power is supplied by the power battery and the diesel generator set. And the grid section and the non-grid section are effectively connected, so that the electrochemical section and the non-electrochemical section achieve an integrated mode. Meanwhile, the auxiliary system is connected to the power battery power supply system, and the voltage class of the power battery loop is lower than that of the intermediate direct-current link, so that the voltage-withstanding class of the auxiliary system isreduced.

The invention discloses an isolated double half-bridge ANPC active bridge three-level DC / DC converter, which comprises two half-bridge ANPC active bridges, an inductor and a transformer. The two half-bridge ANPC active bridges are connected to the two sides of the transformer respectively. Each half-bridge ANPC active bridge circularly outputs a positive level, a zero level, a negative level and azero level. When energy flows from the primary side to the secondary side of the DC / DC converter transformer, the half-bridge ANPC active bridge circuit on the input side of the DC / DC converter is inan inversion state, and the half-bridge ANPC active bridge circuit on the output side of the DC / DC converter is in a rectification state. When energy flows from the secondary side to the primary sideof the DC / DC converter transformer, the half-bridge ANPC active bridge circuit on the input side of the DC / DC converter is in a rectification state, and the half-bridge ANPC active bridge circuit onthe output side of the DC / DC converter is in an inversion state. The voltage stress borne by each switching tube in each half-bridge ANPC active bridge is half of the bus voltage. Low voltage withstanding level, low cost and low switching loss of a switching device are realized through an ANPC three-level circuit.

The invention discloses a novel high-voltage gain mixing direct-current converter for a photovoltaic grid-connected micro-inverter. The novel high-voltage gain mixing direct-current converter consists of an improved novel voltage-multiplying boost converter and a flyback converter and aims at realizing high voltage gain of the converter and reducing the voltage stress of power devices. Since two circuits adopt one input end, the circuit structure is simplified; the output ends of the two circuits are in serial connection with each other to supply the power, so that the overall voltage gain of the mixing converter can be remarkably improved. Through the voltage-multiplying circuit, the voltage gain outputted by the traditional boost circuit can be multiplied, the turn ratio of a transformer in the flyback converter can be reduced, and the reversed blocking voltage stress of an output diode D4 can be effectively alleviated; the leakage inductance energy of the transformer can be recycled through the voltage-multiplying boost circuit, and the system efficiency can be improved; the voltage stress of the main power device can be reduced through a capacitor clamping circuit in the circuit.

The invention discloses a quasi-isobaric discharge isothermal compression energy storage system and method utilizing condensable gas phase change, and aims to solve the problem that an existing isothermal compression air energy storage system does not have the approximate isobaric discharge capacity due to the fact that a single-tank-structure pressure vessel is adopted. Based on the basic principle of an isothermal compression air energy storage technology, water-insoluble condensable gas is adopted as an energy storage working medium, a double-tank-structure pressure vessel and other measures are taken, by means of a liquid piston, spray cooling and other means, hydraulic machinery is used for replacing pneumatic machinery, approximate isobaric discharge of the isothermal compression gasenergy storage system utilizing a condensable gas phase change behavior is achieved, approximate stable power output is provided for special loads, and the system and the method have important practical significance in the aspects of improving the performance of the compression gas energy storage technology, widening the application field of the compression gas energy storage technology and the like.

A plasma processing apparatus comprises a reaction chamber (20), an excitation radio-frequency power source (13), a direct-current power source (24), an upper electrode, and a chip support device disposed in the reaction chamber and at a position relative to the upper electrode, the upper electrode being connected to the excitation radio-frequency power source to generate plasma (10) in the reaction chamber. The chip support device comprises a tray (21) for carrying a chip and a chuck (23), a tray electrode is provided in the tray, the tray is placed on the chuck and is electrically insulated from the chuck, the tray and the chuck are both electrically insulated from the plasma, the tray electrode is electrically connected to a positive output terminal or a negative output terminal of the direct-current power source, a chuck electrode is provided in the chuck, and the chuck electrode is grounded, so that a voltage difference exists between the tray and the chuck and exists between the tray and the chip. The plasma processing apparatus is advantageous in being easy to operate, having high reliability, a simple structure and a low cost, and being not easily damaged.

The invention discloses the research of a model predictive current control method for an open-winding permanent magnet synchronous motor, which belongs to the technical field of permanent magnet synchronous motor model predictive current control. The method is characterized in that the research adopts the open-winding permanent magnet synchronous motor which maintains the stator and rotor structure characteristics of a permanent magnet synchronous motor; and the neutral point of a winding is opened to form the open-winding permanent magnet synchronous motor to increase the output voltage of aconverter. The core idea of the model predictive current control method is to predict the current state quantity of a system at the next moment, and has the advantages of rapid dynamic response and the like. The model predictive current control method is applied to the current loop control system of the open-winding permanent magnet synchronous motor. According to the principle that the dq0 axis current error value is the smallest in vector screening, the zero-sequence current of the open-winding permanent magnet synchronous motor is effectively suppressed.

A control chip of a primary-side feedback switch power source comprises a voltage control unit (101), an RS trigger (102), a chopper unit (103), a driving unit (104), a current control unit (105) and three pins VDD, GND and OUT. The pin OUT outputs to drive an external switch tube after the chopper unit (103) is amplified by the driving unit (104), the voltage control unit (101) and the current control unit (105) are respectively connected with an S end and an R end of the RS trigger (102) respectively to control the chopper unit (103) through the RS trigger. The control chip is characterized in that the pin VDD is used as a feedback voltage collecting point, and the pin OUT is used as a primary-side current signal collecting point. The control chip of the primary-side feedback switch power source solves the problems of high withstand voltage and cost and non-flexible application of a control chip in the prior art.

A inverter of push ¿C pull normal shock three ¿C level DC is prepared as connecting two ends of clamping capacity separately to crossover point of isolation transformer primary winding and three ¿C level branch ad well as crossover point of isolation transformer primary winding b and three ¿C level branch b, connecting the crossing capacity to connection point of power switching tubes on two three ¿C level branches, connecting isolation transformer secondary winding to rectifying and filtering circuit.

The invention discloses a rail transport traction system and an energy feedback system thereof, the energy feedback system comprising: N energy feedback modules, wherein a negative end of each energyfeedback module is connected to a negative end of a DC bus, a positive end of each energy feedback module is connected to a positive end of the DC bus, and each energy feedback module comprises M serially-connected DCDC modules and M energy storage units connected to the corresponding the M serially-connected DCDC modules; and a control unit, wherein by controlling the DCDC module, the control unit causes the M energy storage units to absorb energy of the DC bus or to release the energy to the DC bus, so that a voltage of the DC bus is within a preset voltage range. The system is formed by using multiple energy feedback modules connected in parallel, wherein each energy feedback module is formed by a plurality of serially-connected DCDC modules, thereby effectively reducing the withstand voltage level of a single DCDC module and the power level of each energy feedback module, at the same time, improving the flexibility of the system for power requirements.

The invention discloses a photovoltaic power generation high-voltage DC transmission device and a method thereof. The photovoltaic power generation high-voltage DC transmission device comprises a plurality of photovoltaic units which are connected in series, a plurality of DC-DC converters, a plurality of energy storage units, a plurality of first local controllers, a second local controller and acentral controller. The serially connected photovoltaic units are in circuit connection with the input end of a high-voltage grid-connected inverter. The output end of the high-voltage grid-connectedinverter is connected with an AC power grid. The input ends of the plurality of DC-DC converters are connected with the output ends of the photovoltaic units in the one-to-one correspondence mode. The plurality of energy storage units are connected with the output ends of the plurality of DC-DC converters in the one-to-one correspondence mode. The plurality of first local controllers are connected with the control ends of the plurality of DC-DC converters in the one-to-one correspondence mode. The first local controllers are used for controlling each photovoltaic unit to run at a maximum power point thereof under the preset current of a high-voltage bus. The second local controller is connected with the control end of the high-voltage grid-connected inverter. According to the invention, the DC-DC converters are not directly connected with a high-voltage DC bus, so that the cost is reduced. The power generation efficiency is improved. Meanwhile, the generation of the hot spot phenomenon is avoided as much as possible.

The invention provides a triple phase shift control method and control device for a dual-active bridge circuit, and the dual-active bridge circuit comprises three-level plus three-level, three-level plus two-level, and two-level plus three-level. The method comprises the following steps: selecting a circuit structure according to the voltage ranges of an input voltage source and an output voltage source of the dual-active bridge circuit and the withstand voltage range of a switching tube; judging phase shift modes, including a step-down triple phase shift mode and a step-up triple phase shift mode; according to the equivalent voltage of the input voltage source, the equivalent voltage of the output voltage source and the closed-loop control quantity of the dual-active bridge circuit, calculating corresponding triple phase shift angles in different phase shift modes; and performing phase shift control according to the triple phase shift angle. According to the method, a proper dual-active bridge circuit topology is selected according to different voltage levels, the voltage withstand level of a switching tube is reduced, the combination mode is flexible, the cost is saved, triple phase shift control is adopted for the selected topology, the switching-on loss of the switching tube can be reduced, and the working efficiency of the dual-active full-bridge circuit is improved.

The invention relates to a novel method for vulcanizing rubber-insulated electric wires and cables, belonging to vulcanizing method of rubber-insulated electric wires and cables. The method comprises the following steps: injecting nitrogen gas with the pressure of 0.5-0.7MPa into a vulcanized conduit or a container; carrying out galvanothermy radiating heating on the electric wires and cables through the vulcanized conduit or the container, and the galvanothermy radiating temperature is 240 DEG C-400 DEGC. The invention has the advantages of lowering the pressure level of the vulcanized system and more easily realizing encapsulation of nitrogen gas. The max temperature of galvanothermy radiation can reach 400 DEG C so as to facilitate the application of high-temperature rapid vulcanized system and intelligent advance equipment to be possible. The vulcanized cable has smooth surface resulting from that vulcanizing medium environment is dry without moisture. The invention has the advantages of saving investment, avoiding pollution to the air and the environment by the coal burning boiler, thus having bright popularization prospect.

A power grid voltage supporting type modularized active power filter and a control algorithm are provided and belong to an active power filter and a control algorithm. The topology of the active power filter is a serial combination structure of a power grid voltage supporting portion and an active filtering portion. Each phase of the power grid and voltage support portion consists of n power grid voltage supporting module units connected in series, and each unit consists of an H-bridge circuit and a shunt capacitor; and the active filtering portion consists of m active filtering module units connected in parallel, and each unit consists of a three-phase full-bridge circuit, an AC filtering inductor and a shunt capacitor. The power grid voltage supporting portion adopts a carrier phase-shifting modulation technique to track a grid-side voltage of a common coupling point, so as to reduce voltage demands at the DC side of the active portion; and the active filtering portion adopts an improved current prediction technique to track a harmonic current, so as to be adapted to the power grid voltage supporting structure. The algorithm has the advantages of low costs, high reliability, strong universality, and easy extension, and can be widely used in harmonic treatments in high voltage and high power occasions such as petroleum mining and precision manufacturing and tiny weak power grids.

A flexible on-load voltage regulator of an integrated flexible AC power transmission device comprises a main voltage regulator (10), a voltage regulation transformer (20), a flexible AC power transmission electronic device (30) and a controller (40), wherein a tap is arranged on a high-voltage side, connected with a power grid, of the main voltage regulator (10), the main voltage regulator (10) is connected with the voltage regulation transformer (20) through the tap, the voltage regulation transformer (20) shares a part of winding of the main voltage regulator (10), the voltage regulation transformer (20) is connected with the flexible AC power transmission electronic device (30), the flexible AC power transmission electronic device (30) is connected with the controller (40), the controller (40) is used for simultaneously sampling the voltage of the power grid and a filter current output from the flexible AC power transmission electronic device for feedback control according to a given voltage regulation instruction, the obtained driving pulse instruction is generated to a required compensation voltage, the required compensation voltage is sent to the main voltage regulator (10) through the voltage regulation transformer (20), the voltage of the high-voltage side of the main transformer (10) is changed, and stepless and rapid regulation on the voltage of a load side is further achieved.

The invention discloses a fan control system of an air conditioner and the air conditioner. The system comprises a fan drive, a power accumulator and a DC / DC converter, wherein the fan drive is matched with a fan for driving the fan to operate; the power accumulator is matched with the fan drive for supplying electricity to the fan by power supply voltage when the voltage needed by the fan is the same with the power supply voltage of the power accumulator; or the DC / DC converter is respectively matched with the power accumulator and the fan drive in sequence for converting the power supply voltage to conversion voltage same with the voltage needed by the fan when the voltage needed by the fan is different from the power supply voltage and supplying electricity to the fan by the conversion voltage. The system can overcome such defects as high electromagnetic disturbance, weak reliability and low efficiency in the prior, and achieves the beneficial effects of low electromagnetic disturbance, high reliability and high efficiency.

The invention provides an electromagnetic levitation train track system, tracks are arranged on two sides of a roadbed or a track beam, a magnetic levitation train runs on the tracks, the system is characterized in that traction guide electromagnets are horizontally arranged on supporting arms on two sides of the magnetic levitation train, and linear motor stators are horizontally arranged at opposite positions on the tracks, a linear motor stator and a traction guide electromagnet are horizontally arranged in the magnetic pole direction, an iron core linear motor is formed by the linear motorstator and the traction guide electromagnet at a certain magnetic gap, and an E-shaped section suspension electromagnet and a gap sensor are arranged at the bottom of the maglev train and suspended below an armature plate horizontally arranged at the bottom of a rail. The control system controls the current and direction of the traction guide electromagnet and the linear motor stator coil, and controls the horizontal guide and suspension force and the traction force and direction, so that the maglev train flies in the air.

The invention provides a damping circuit and an LED driving circuit with the damping circuit. A damping circuit includes a damping element, a control circuit, and a control switch. The damping elementis electrically connected to the DC bus bar. The control circuit obtains a supply voltage from the DC bus and compares the supply voltage with a threshold voltage. When the DC bus voltage is higher than the threshold voltage, the control circuit outputs a first control signal. The control switch is electrically connected to the damping element and the control circuit respectively, and the controlswitch cuts the damping element into the circuit based on the first control signal output from the control circuit. By setting a damping circuit in the LED drive circuit, the voltage on the DC bus bar can be effectively restrained from rising in the start-up phase, and the withstand voltage level of the latter stage circuit can be effectively reduced, so that the LED drive is compatible with theelectronic ballast.

The invention relates to an energy taking circuit used in series with a power module equalizing resistor. A capacitor positive pole of a power unit is taken as a voltage input end HVin, and two powersupply power sources VOUT1 and VOUT2 are outputted. A voltage equalizing resistor, a first full control switching device, a rectifier diode, a first voltage sampling circuit, a driving circuit, a starting circuit, a starting capacitor, a storage capacitor, a second voltage sampling circuit, a main control circuit, a power conversion circuit and a power supply diode are included. The energy takingcircuit is independent of an original energy taking power source on a power module, when the original energy taking power source fails, standby power supply can be provided for a bypass contactor trigger circuit of the power unit to ensure reliable implementation of the contactor bypass action. The energy taking circuit is connected with a power unit capacitor after being connected in series withthe equalizing resistor, voltage withstanding levels of a full control device and the storage capacitor are reduced, and design convenience is high. The energy taking circuit is advantaged in that thecircuit principle is concise, reliability is high, the VOUT1 and VOUT2 dual power source output function is achieved, and flexible application is achieved.