1838results about How to "Stable voltage" patented technology

A substrate processing apparatus capable of removing signal interference between reactors includes: a first reactor, a second reactor adjacent to the first reactor, and a power generator configured to supply first power to the first reactor and supply second power to the second reactor, wherein the power generator is further configured to synchronize phases of the first power and the second power.

An electric supercapacitor module is utilized as the primary power source for the propulsion unit of electrically powered vehicles. The vehicle operates in conjunction with roadway embedded wireless chargers which continually charge the vehicle's supercapacitor while the vehicle is in motion to maintain the motion and materially increase the vehicle's range without limitation.

The invention relates to the technical field of photovoltaic micro-grid control, and particularly discloses a real-time coordination and control method of a photovoltaic micro-grid system. A central real-time optimal control layer and a local control layer are involved in the real-time coordination and control method. The central real-time optimal control layer collects the voltage and frequency of an AC bus of the photovoltaic micro-grid system, the charge state of a storage battery pack, the output power of photovoltaic power generation micro-sources, the output power of the storage battery pack, the output power of a super capacitor and the real-time power of a load in real time, generates a real-time coordination and control strategy and a secondary frequency modulation and scheduling plan, and issues the strategy and the plan to all local controllers. The local control layer coordinates and controls all the micro-sources in real time, and particularly achieves the scheduling plan issued by the central real-time optimal control layer. According to the real-time coordination and control method, a micro-grid central optimizing controller can manage, coordinate and control all the local controllers in a unified mode, the micro-grid can efficiently and economically run, the output power of the photovoltaic power generation unit is utilized to the maximum extent, the output power fluctuation and the tracking load change of the photovoltaic power generation unit are restrained, the running method of the micro-grid is reasonably adjusted, and energy balance is achieved.

A voltage reference circuit including a positive temperature coefficient current generator, a negative temperature coefficient current generator, and a first resistor is provided. In the positive temperature coefficient current generator, two transistors are operated in the weak inversion region, and a second resistor is connected in series between the gates of the two transistors. The second resistor employs the characteristic that a transistor operated in weak inversion region acts like a bipolar junction transistor to generate a positive temperature coefficient current. The negative temperature coefficient current generator generates a negative temperature coefficient current in response to a negative temperature coefficient voltage drop on a third resistor. The positive temperature coefficient current and the negative temperature coefficient current flow through the first resistor together, thus producing a stable reference voltage.

The invention provides a control method of a grid friendly type distributed power source based on hybrid energy storage. The method comprises the steps of optimally designing a topology structure of the distributed power source, controlling a direct current power supply system in a coordinating mode through a direct current (DC) / DC converter controlling a model normalization model, and self-adaptively controlling a grid of an alternating current (AC) side DC / AC converter. The distributed power source not only can be connected in a large grid to operate so as to reduce the influence of intermittent renewable energy power generation grid connection on the grid and provide support of voltage and frequency for the grid, but also can be connected into a micro-grid to operate as a network unit of the off-network type micro-grid to maintain stability of voltage and frequency of the off-network type micro-grid. When an outer grid breaks down, the distributed power source can realize switch between a grid mode and an island mode so as to improve power supply reliability of important loads in the system. The distributed power source improves technical performance and economic performance of the whole system through matching utilization of an energy type system and a power type energy storage system.

The invention discloses a method and a system for recovering regenerative brake energy of an energy storage type urban rail based on a supercapacitor. The method comprises the following steps of connecting a direct current traction network of the urban rail through a chopping unit and a supercapacitor unit, wherein the chopping unit comprises two bidirectional chopping module units; according to the connecting type of the two bidirectional chopping module units of the direct current traction network, and the voltages of the direct current network and the supercapacitor, controlling the charging and discharging of the supercapacitor unit. The system comprises the chopping unit, the supercapacitor unit, a chopping control module and a direct current isolation switch unit, wherein the chopping unit comprises the two bidirectional chopping module units which are connected in series or parallel, and each bidirectional chopping module unit comprise one or more than one bidirectional DC / DC (direct current / direct current) chopping module which is connected in parallel. The method and the system have the advantages that the regenerative brake energy of the urban rail can be recovered and fed back, and the method and the system can be applied to the common DC1500V / DC750V direct current traction networks; the universality is strong, the reliability is high, the stability is good, the production cost is low, and the flexibility is high.

The invention provides a direct-current (DC) microgrid system and an energy management method thereof. A power generation unit comprises a large user-side power grid and a grid-connected alternating current / direct current converter (AC / DC) thereof, a lithium iron phosphate energy storage system (EMS) and an energy storage direct current / direct current converter (DC / DC), and a photovoltaic power generation system and a photovoltaic DC / DC thereof. The DC microgrid system is provided with EMS and a wireless sensor network thereof, wherein the wireless sensor network is communicated with the grid-connected, energy storage and photovoltaic DC / DC; the EMS is used for executing different control strategies and optimizing the operation of a DC microgrid; the voltage of a DC busbar is stabilized by controlling a DC busbar voltage outer loop and an output inductive current inner loop through the grid-connected AC / DC when a grid-connected operation is switched to an islanding operation; and the islanding operation is switched to an operation using the energy storage DC / DC as a voltage source, i.e. the voltage stability of the DC busbar is maintained by controlling the DC busbar voltage outer loop and the inductive current inner loop on the energy storage side of a battery within the time of at most 20ms. Therefore, a seamless switching requirement is met, uninterrupted power supply (UPS) of loads in a telecom data center is realized, and configuration of reactive-load compensation equipment is avoided.

The invention discloses a grid-connected non-networking micro-grid system and a control protection method thereof. On the premise of basically not changing the structure of the original power distribution system, multiple types of distributed power sources, such as wind power generation system, photovoltaic power generation system, cell accumulation system and the like, are connected into a common power grid along with user loads through AC buses, and reasonable load layout and active energy management are utilized to implement grid-connected non-networking of the micro-grid system. By using the structural design and the active energy management of the micro-grid central control unit, the new energy power generation system can be completely self-sufficient, and does not reversely transmit power to the common power grid, thereby avoiding impacting the normal power supply of the common power grid; and meanwhile, by the aid of the common power grid, the user loads have higher power supply reliability and electric power quality.

The invention relates to a single-phase universal electric energy quality controller for power supply for electrified railways, and belongs to the technical field of flexible AC power transmission and distribution; the invention comprises a single-phase multi-coil transformer composed of a primary coil and n secondary coils, so that the secondary coils of the transformer can be connected in parallel with n voltage sources of current transformers; n capacitors are connected with n voltage source current transformers, so as to form a single-phase chain-type H-bridge current transformer with n chains; the AC terminal of the H-bridge current transformer is directly connected with the traction grid through a reactor. The invention has the functions of active power control, reactive power compensation and harmonic compensation, so as to resolve three-phase voltage unbalance, voltage fluctuation, low power factor and harmonic pollution and so on that exist in ER traction transformer stations, effectively lower the capacity of traction transformers, increase ER transport capacity and transportation capability. Moreover, the invention is characterized in small occupied area, little loss and low cost, in order to gain perfect harmonic suppression characteristics and dynamic response features, and provide convenience in industrial production and improve device reliability.

The invention discloses a direct current transmission system based on a three-pole type structure. The direct current transmission system comprises a rectifying converter station and an inverting converter station, wherein the rectifying converter station and the inverting converter station respectively adopt a three-pole converter system, each three-pole converter system consists of three converter units H1, H2 and H3, each converter unit H1 and each converter unit H2 respectively adopt a modularized multilevel converter based on a CDSM (clamp dual submodule), and each converter unit H3 adopts a modularized multilevel converter based on an FBSM (full-bridge submodule). The direct current transmission system has the advantages that the CDSM and the FBSM do not need the support by an alternating current voltage source during conversion of alternating current and direction current, and the power can be supplied to a passive load; the harmonic property of the three-pole direct current is higher, the direct current latching capability is realized, meanwhile, the power and powerless decoupling controls can be realized, and the additional powerless compensation and filtering equipment are not needed; and the overvoltage phenomenon is avoided when the load shedding occurs.

A semiconductor device includes a body region, a drift region having a first part and a second part, and a trench gate electrode. The body region is disposed on the drift region. The first and second parts extend in an extending direction so that the second part is adjacent to the first part. The trench gate electrode penetrates the body region and reaches the drift region so that the trench gate electrode faces the body region and the drift region through an insulation layer. The trench gate electrode extends in a direction crossing with the extending direction of the first and second parts. The first part includes a portion near the trench gate electrode, which has an impurity concentration equal to or lower than that of the body region.

The invention discloses a tri-pole direct current transmission system topology structure based on an MMC. The tri-pole direct current transmission system topology structure is characterized in that direct current transmission is performed in a tri-pole connecting mode, and each pole comprises a rectification-side converter transformer, a rectification-side converter, a rectification-side smoothing reactor, a direct current transmission line, an inversion-side smoothing reactor, an inversion-side converter and an inversion-side converter transformer group. The rectification-side converters and the inversion-side converters are in modular multi-level structures, sub-modules of different amounts are connected in series and in parallel to be adapted to requirements for different voltage classes and currents, and three transmission lines used in a tri-pole direct current system are cables or overhead lines. The tri-pole direct current transmission system topology structure is high in reliability and capable of meeting the requirement for changing alternating current lines into direct current lines, phase change failures on the inversion side can be avoided under the condition that an alternating current system breaks down, voltages on two sides of the alternating current system can be stabilized, a alternating current filtering and reactive compensation device is not needed, and good application values are provided.

In a liquid crystal drive controller formed as a semiconductor integrated circuit having therein a power source circuit including a boosting circuit and driving a source line and a gate line of a TFT liquid crystal panel, the number of external capacitive elements and the number of external terminals for connecting the external capacitive elements are reduced, thereby reducing the size and cost of the chip and an electronic device on which the chip is mounted. As a boosting circuit for generating a voltage for driving a source line of the TFT liquid crystal panel in the liquid crystal controller having therein the power source including the boosting circuit, a boosting circuit having an external capacitive element is used. On the other hand, as a boosting circuit for generating a voltage for driving a gate line, a charge pump having a built-in (on-chip) capacitive element is used.

The invention provides a composite energy storage system, which consists of a supercapacitor and a storage battery, wherein the composite energy storage formed by the supercapacitor and the storage battery has both power type and energy type characteristics; through the combined use, the charging and discharging times of the storage battery can be effectively reduced; in addition, the utilization rate of the energy storage system can be improved. According to an energy management and control optimization method matched with the composite energy storage, the total power of the composite energy storage is distributed through a low-pass filter, so that the supercapacitor and the storage battery respectively share a high-frequency component and a low-frequency component in the fluctuating power; through the two-way DC / DC1 converter constant-power control on the storage battery, the two-way DC / DC2 converter constant bus voltage control on the supercapacitor, and control strategies of the two-way DC / AC converter, the network loss of a power distribution network is reduced; the utilization efficiency of new energy sources is improved; the power fluctuation during micro power grid interconnection is effectively inhibited; the electric energy quality of a region electric network is improved; in an offline state, the stability of the voltage and the frequency of a micro power grid system can be ensured; the power balance generated during grid connection / off-grid switching is fast compensated.

A switching power supply unit which contains a secondary battery for backup and a circuit for controlling the charging and discharging of the secondary battery in its enclosure and which properly manages the charging and discharging of the secondary battery. A switching power supply circuit includes a rectifying and smoothing circuit for smoothing alternating-current input from commercial power supply Vin at normal operation time, a battery pack charged by a DC—DC converter which can continuously output a predetermined direct-current power supply voltage for supplying power supply voltage to the DC—DC converter at the time of a stoppage in alternating-current input, a charging circuit section for controlling the charging and discharging of the battery pack, and a charging and discharging control circuit. The battery pack and circuits, such as the DC—DC converter, are mounted in the same unit enclosure.

The invention discloses a voltage detection and power failure protection device, which is used for keeping the voltage stability of a load. The device comprises a voltage detection module, a voltage stabilization circuit module, an energy storage and power supply module, a control module, a switch module and a power supply switching voltage stabilization module, wherein the switch module comprises a second switch and a third switch; a power supply is connected with one end of each of the second switch, the energy storage and power supply module and the voltage detection module; the other end of the second switch is connected with one end of the voltage stabilization circuit module; the other end of the energy storage and power supply module is connected with one end of the third switch; the other end of each of the voltage stabilization circuit module and the third switch is connected with the load by the power supply switching voltage stabilization module; and the control module is connected with the second switch, the third switch, the voltage detection module and the power supply switching voltage stabilization module. The voltage detection and power failure protection device provided by the invention can keep the power supply voltage stability of the load when the output of the power supply is instable, and may not cause voltage fluctuations of the load, thereby meeting the requirements of a user on the voltage stability of the load.

The invention discloses a display panel and a display device. A threshold compensation circuit comprises a first threshold compensation transistor, a second threshold compensation transistor and a shielding capacitor. Wherein a first threshold compensation transistor and a second threshold compensation transistor are arranged; the length L of the channel region of the transistor can be increased equivalently, and the current I of the transistor is inversely proportional to the length L of the channel region, so that when the length L of the channel region is increased, the current I of the transistor can be reduced, and the quantity of charges flowing into the node N1 from the node N4 can be reduced. Moreover, by arranging the shielding capacitor, the charge of the node N4 can be stored inthe shielding capacitor by utilizing the charge storage effect of the shielding capacitor. Therefore, during signal switching on the scanning signal line, charges of the node N4 can be prevented frombeing injected into the node N1, so that the voltage of the grid electrode of the driving transistor can be kept stable, and the display uniformity of the display panel is improved.

The invention provides an on / off-grid control method for a microgrid with a plurality of distributed power supplies. When the microgrid is on on-grid operation, a central controller of the microgrid can continuously carry out isolated island detection. When the microgrid is detected to be in an isolated island operation state, isolated island operation control is carried out according to a preset strategy. When the microgrid is in an off-grid operation state, the central controller of the microgrid can start an on-grid process to achieve the positive sequence voltage amplitude of the large power grid side, the frequency of the large power grid side, the frequency of the microgrid side, the voltage of the large power grid side, the voltage of the microgrid side, the voltage phase angle value of the large power grid side and the voltage phase angle value of the microgrid side. Whether the microgrid is suitable for on-grid operation is judged by comparing the relationship between correlation values and preset values. If on yes judgment, the central controller of the microgrid can control the breakers to be switched on to achieve grid connection. The control method can achieve the on / off-grid control on the microgrid with distributed power supplies, avoids long-time off-grid operation of the mcirogrid and can timely break the mcirogrid to enable the microgrid to operate normally when a larger power grid is broken down.

The invention relates to a lithium ferric manganese phosphate as a cathode material of a lithium ion battery and a preparation method thereof, belonging to the technical field of lithium ion batteries. The lithium ferric manganese phosphate as the cathode material has a chemical composition: Li1-yMyFel-xMnxPO4. The preparation method of the lithium ferric manganese phosphate as the cathode material comprises the following steps of: (1) synthesizing a precursor: placing raw materials into a container; adding a dispersant; grinding and dispersing 1-3 hours at rotation speed of 1000-2500r / min; and drying and grinding pasty paste; (2) preburning: heating to the temperature of 350-550 DEG C according to a heating rate of 1-10 DEG C / min; preburning 3-20 hours at constant temperature; cooling to room temperature along with a furnace; and preparing the lithium ferric manganese phosphate; and (3) coating carbon at high temperature: mixing and dispersing the lithium ferric manganese phosphate, a carbon source and the dispersant 1-3 hours; after drying, heating to the temperature of 600-850 DEG C by using a heating rate of 1-10 DEG C / min; insulating 3-20 hours; cooling to room temperature along with the furnace; and preparing the lithium ferric manganese phosphate. The invention has the advantages of simple technology, low cost of batteries, high safety of cathode materials, high thermal stability, electric conductivity increase, and the like.

The invention discloses a reactive voltage control method of a photovoltaic power station, which uses a photovoltatic power station synchronization point as a control target and reactive power as a regulating quantity. According to the reactive demand of the photovoltaic power station, a reactive power supply of the photovoltaic power station is integrally planed, the reactive output of each photovoltaic inverter and reactive compensating device in the photovoltaic power station is determined, and coordination control of the photovoltaic inverters and the reactive compensating devices in the photovoltaic power station is realized; and protection restraint conditions of the photovoltaic inverters and the reactive compensating devices are fully considered, and the photovoltaic inverters and the reactive compensating devices, which do not meet the restraint conditions, do not participate in the reactive voltage control. The control method provided by the invention can ensure that the reactive output of the photovoltaic power station synchronization point meets the system load change and inhibits the bus voltage fluctuation caused by load change, and has the function of maintaining the voltage of the photovoltaic power station synchronization point to be stable.

An illuminating device for killing and / or interfering with pests, which includes at least one light emitting diode for producing more than one non-parallel integrated pulse light that is centralized in a narrow wave band. A wavelength of the integrated light is in a range from 584 nm to 618 nm, a frequency thereof is in a range from 514 THZ to 485 THZ, and a view angle thereof is less than 45 degrees. In addition, an illuminating system for killing and / or interfering with pests includes a drive for driving the illuminating device to emit the integrated pulse light. Also, a method for killing and / or interfering with pests is provided. The method utilizes above illuminating device and system to produce a non-continuous, non-parallel integrated pulse light to kill, interfere with or dispel insect pest.

The invention relates to a unified power energy quality controller based on the serial-connection multiplicity of transformers and a chain structure, which belongs to the technical filed of flexible AC transmission and distribution of an electric power system and the power electronic. The unified power quality controller comprises a single-phase serial-connection multiple transformer bank and a single-phase chain H bridge converter, wherein the transformer bank consists of m single-phase transformers which form the serial-connection multiple transformer bank together with n voltage source converters connected with n secondary windings of m single-phase transformers respectively; the single-phase chain H bridge converter is provided with n chains and is formed by connecting n DC voltage supporting units and n power source converters, and an AC port of the n-chain single-phase chain H bridge converter is directly connected with the electric fence through a reactor, m and n are signless integrals equal to or more than 2, and m is less than or equal to n. The invention can realize accurate current control, has high dynamic responding speed, and can solve the problems of the traction substation of an electrified railway that the three-phase voltage is unstable and fluctuates, the power factor is low and the harmonic pollution exists, and the like.

A driving circuit of a light emitting diode (LED) includes a rectifier unit, a voltage-dividing circuit, a control unit, a voltage converter, a resistance and a capacitor. The rectifier unit rectifies an AC power to generate a first operation voltage. The voltage-dividing circuit generates a voltage-dividing signal. The control unit includes a regulating unit and a pulse width modulation (PWM) unit. An output terminal of the regulating unit is coupled to the PWM unit. The PWM unit outputs a PWM signal. The voltage converter adjusts a driving voltage and a driving current of the LED. The resistance is coupled between an output terminal of the regulating unit and a diode. The capacitor is coupled between a power input terminal of the regulating unit and a ground terminal. The PWM unit adjusts the PWM signal according to the voltage-dividing signal and a feedback signal output by the voltage converter.

The invention relates to a distributed energy management method and device. The distributed energy management device is composed of a ground layer, an intermediate layer and an energy management layer. The ground layer comprises a distributed power controller, an energy storage controller, a load controller, an invertor, a converter and a breaker. The intermediate layer comprises a data communication module, an operation control module, an energy storage management module and a load management module. The energy management layer comprises a data communication and monitoring module, an economic dispatch and optimal operation module, a load prediction module and a power generation prediction module. The ground layer and the intermediate layer coordinate and control short-term power in a local micro-grid system to be stable; the energy management layer coordinates and controls long-term power in the micro-grid system where the energy management layer belongs to be stable, and economization of micro-grid operation is achieved; meanwhile, the distributed energy management device is clear in structure, functions are specific, and system upgrade and function extension are facilitated.

The invention relates to a multi-mode switching coordination control method for a direct current micro-grid system. Specific models are built for each micro-grid unit in the micro-grid system, working modes of the operation of the system are divided, various disturbance influences in various modes are full considered, and stable operation of the system in grid-connected and off-grid operation stable state and various disturbances thereof such as mutual switching and load and generating fluctuation is realized. According to the method, according to the load bus voltage and specific condition, the control strategy is reasonably adjusted, and the system can operate in a stable manner in different working modes and conditions; the micro-grid units and the coordination control method between the micro-grid units are controlled regarding the voltage as the control main body, stable operation of the system is guaranteed, frequent power exchange between the micro-grid units is avoided, and the power consumption is reduced; and compared with the prior art, the power grade of a converter is reduced, the system security and the reliability of energy storage are improved, and the failure rate due to an energy storage system is reduced.

The invention discloses a DC bus distributed MPPT photovoltaic power generation system. The system comprises a photovoltaic cell array, a DC conflux boosting unit, a grid-connected inverter unit and an AC boosting unit, wherein the photovoltaic cell array, the DC conflux boosting unit, the grid-connected inverter unit and the AC boosting unit are connected in sequence; the photovoltaic cell array is composed of one or more cell arrays; the DC conflux boosting unit is composed of one or more DC power sources, and the intelligent DC power sources are used for boosting variable photovoltaic cell voltages sent by the photovoltaic cell array into stable high voltages; the grid-connected inverter unit comprises an inverter and is used for stabilizing output voltages of the DC conflux boosting unit and being responsible for start and stop of the working logic of the whole system; the AC boosting unit comprises a transformer. The DC bus distributed MPPT photovoltaic power generation system has the advantages of being simple in structure, low in cost, capable of improving the overall efficiency and the like.

A wireless earphone communicates with a mobile phone by wireless and comprises a microprocessor, a feedback-type charging circuit and a rechargeable battery therein. The microprocessor output control signals to control the feedback-type charging circuit for charging the rechargeable battery; the feedback-type charging circuit also feeds back the charging current and charging states of the rechargeable battery to the microprocessor. Therefore, the microprocessor may change the charging current depending on the states of the rechargeable battery. By changing the voltage of the control signals, the charging current of the feedback-type charging circuit can be adjusted by the microprocessor. The present invention provides a charging design by software control to reduce the production cost of wireless earphone.

A soft-stop overvoltage protection circuit, into which a soft-stop overvoltage detection voltage proportional to a direct current output voltage is input, reduces the output of a multiplier in accordance with the soft-stop overvoltage detection voltage when the soft-stop overvoltage detection voltage exceeds a first threshold value. An overvoltage protection circuit, a second threshold value higher than the first threshold value being set, compulsorily turns off a switching element by outputting an overvoltage detection signal when the soft-stop overvoltage detection voltage exceeds the second threshold value. The soft-stop overvoltage protection circuit compulsorily increases the output of a voltage error amplifier circuit on the output voltage decreasing. When the output of the voltage error amplifier circuit increases suddenly, and the output voltage rises excessively, the soft-stop overvoltage protection circuit decreases the output of the multiplier, thus curbing the rise of the output voltage.

The invention discloses an intelligent control module of a permanent magnet contactor, which mainly comprises a microprocessor, a rectifier and filter, an internal working power circuit, a rechargeable battery control circuit, a closing operation module, an opening operation module, an energy-storage capacitor voltage detection circuit, a control voltage detection circuit, a power off detection circuit, and a key-press setting and display control circuit; wherein, the closing operation module consists of a first MOSFET driving protection circuit and a first MOSFET; and the opening operation module consists of a second MOSFET driving protection circuit and a second MOSFET. The intelligent control module can set delay time parameters of transient interference electricity through key-presses according to requirements of a customer, realizes delay disconnection of the permanent magnet contactor and can ensure the stable and continuous operation of equipment through staying away from influences of interference electricity; and as for conditions of requiring urgent opening operation, the intelligent control module can immediately cut off the contactor through key-press control, so as to ensure the safety of the operating equipment.

The invention discloses an AC electrified railway traction in-phase power supply device based on a YNd11 connection transformer, the traction transformer of the device is a three-phase transformer (T1) connected in YNd11, and the three primary sides of the transformer (T1) in a YN connection The three phases A, B, and C are connected to the high-voltage public power grid, and the low-voltage side terminals (a, b, c) of the transformer are connected to a power flow controller (IC), and the terminals a and b are connected to the electrified railway catenary (TR) . The device can realize the same-phase power supply for the entire railway line without phase separation, and the power supply voltage is stable, ensuring the high-speed and heavy-load operation of the locomotive; at the same time, the device can eliminate the negative sequence, reactive power and harmonics of the railway traction load on the electric energy of the public grid impact, low cost, and easy implementation.