30results about How to "High quality power supply" patented technology

The invention discloses a STATCOM (static synchronous compensator) control system adopting a droop control strategy and a control method thereof. The STATCOM control system adopting the droop control strategy comprises a direct-current side capacitor, a three-phase inverter bridge and an inductance-capacitance filter, wherein the direct-current side capacitor and the three-phase inverter bridge are connected in parallel and then connected with the inductance-capacitance filter, and the inductance-capacitance filter is connected to a PCC (Point of Common Coupling) of a power grid by a three-phase switch K through a coupling transformer T. The control method disclosed by the invention comprises the steps of real-time signal collection, computation of active power reference value P*, computation of reactive power reference value Q*, computation of frequency reference value omega* and voltage modulation amplitude reference value E*, computation of phase reference value Delta* and computation of voltage modulation signals; and only one PI (proportional integral) regulator and two droop control coefficients need to be regulated, thus the whole control method is easy to realize, and further the power system can better supply power to users safely, excellently and economically.

The energy storage system according to one embodiment comprises a first converter connected between the system and the DC distribution network, and converting an AC voltage of the system into a DC voltage and transmitting the DC voltage to the DC distribution network; a second converter connected to the DC distribution network and controlling the voltage of the DC distribution network; a battery connected to the second converter and of which the charging and discharging are controlled by the second converter; a third converter connected to the DC distribution network; and a first load connected to the third converter and of which the voltage is controlled by means of the third converter, wherein the first converter generates a power control instruction for controlling at least one of the battery and the first load on the basis of SOC information of the battery and power consumption information of the first load.

An image forming apparatus that ensures high-quality power supply to an AFE (analog front-end) and reduces the amount of power consumed by the AFE in sleep mode. The AFE, which converts an analog signal into a digital signal, and another circuit different from the AFE are incorporated in an SOC (system-on-a-chip). A switch circuit switches power to the AFE between first DC power supply from a 5-V / 3.3-V_LDO and second DC power from a 24-V / 3.3-V_DC-DC converter. When the AFE is in use, the switch circuit is controlled such that the first DC power is supplied from the 5-V / 3.3-V_LDO to the AFE, and when the AFE is not in use, the switch circuit is controlled such that the second DC power is supplied from the 24-V / 3.3-V_DC-DC converter to the AFE.

The invention provides a control method for synchronous closing and grid-connection of a microgrid group, which includes: respectively measuring the voltage amplitude, voltage frequency and voltage phase difference on the side of the distribution network and the side of the microgrid group with a voltage transformer; The voltage and frequency set the output voltage and frequency target value of the AC / DC conversion unit on the microgrid group side; the communication bus sends a broadcast message to the AC / DC conversion unit; after a predetermined time, the phase-locked loop follows the frequency and phase of the distribution network side output voltage frequency; the communication bus sends a broadcast message to the AC / DC conversion unit; and the synchronous closing controller of the microgrid group sends a closing command. The grid-connected frequency is controlled by the inverter based on the power electronic interface control provided by the present invention, so that the voltage amplitude, frequency and phase of the microgrid side and the distribution network side are exactly the same, the adjustment accuracy is high, and the impact of closing surge current is reduced .

The invention relates to a bundled conductor aeolian vibration determination method considering a spacer damping parameter. The method is based on spacer line clamp damping parameter computational analysis and experimental study and combines a spacer average subspan calculation method, the real spacer damping is applied to a proper position of a bundled conductor, and finally, solution of bundled conductor aeolian vibration is realized with a finite element method, so that the bundled conductor aeolian vibration level is determined, and a reference is provided for anti-vibration design of lines. The method can make up defects of solving bundled conductor aeolian vibration on the basis of a traditional reduction factor method.

The invention discloses a braking energy self-adaptive recovery device and a recovery method for an EMU, belonging to the technical field of dynamic electric energy recovery braking, including: two sets of converters; data for obtaining current data on each power supply arm Collector; an energy storage device that realizes the storage or release of braking energy and completes two-way conduction of electric energy between two sets of converter devices; receives data from the data collector, analyzes and processes the data, and then controls the converter device, The control unit for the operation of the energy storage device; the converter device transforms and converts the traction power supply to obtain a 10kV power supply for the railway through power supply or self-closing power supply; the DC buses of the two converter devices are connected through the energy storage device. The invention realizes the flexible transfer of braking energy between the two traction arms, the remaining braking energy is temporarily stored in the energy storage device, and after the braking of the EMU, the energy in the energy storage device is gradually transferred to the Rail penetration or self-closing load release.

The invention discloses a power island, comprising an SPC (Source Power Conditioner), an LPC (Load Power Conditioner), a DCS (DC Converter System), an emergency power supply system and an AC bus, wherein the SPC is formed by m sets of three single-phase conversion systems composed of 3m series transformers and 3m single-phase convertors; the LPC is formed by n sets of three single-phase conversion systems composed of 3n series transformers and 3n single-phase convertors; the DCS is formed by two sets of three-phase three-wire convertors spare for each other and a DC bus. According to the invention, m paths of power supply provide power for n paths of important loads through the power island; the power island can realize the seamless switching among a plurality of paths of power supply, rapid voltage support, seamless grid connection of an emergency power supply system, and maintenance of load normal work, and meanwhile realize voltage harmonic wave, current harmonic wave, and reactive power compensation; in addition, the power island can restrain impact load active fluctuation, realize peak load shifting, and eliminate the circulation caused by direct parallel connection of a plurality of paths of power supply or active loads; besides, the power island can isolate the fault current generated in case of load faults, and meet the requirements of high reliability and high quality for electric energy by important loads.

The invention relates to a portable insulation safety tool power frequency withstand voltage test trolley, which comprises: a car body part; a clamping part; a conductive part; a measuring part and a storage part. The portable insulating safety tool power frequency withstand voltage test trolley of the present invention can meet the power frequency withstand voltage test of various safety tools such as insulating gloves, insulating boots, insulating rods, electroscopes, grounding wires, insulating partitions, insulating rubber pads, etc. Require. It saves a lot of manpower and material resources, reduces the occurrence of safety accidents, and has good economic and social benefits. And because the application of the test trolley of the present invention reduces the number of vehicles used by the porters, it can also bring considerable environmental benefits.

The invention discloses an emergency adjustment system for three-phase electric unbalance, which comprises a grid input unit, a DC battery unit, an AC output unit, a control unit, and a signal acquisition unit; the grid input unit includes an input contactor, an AC fuse, a direct supply Contactors, load contactors; DC battery units include single-phase controllable rectifiers, filter reactors, filter capacitors, isolation diodes, DC switches, DC fuses, battery packs; AC output units include three-phase full-bridge inverters , filter reactor, and output contactor; the signal acquisition unit is respectively connected to the voltage monitoring terminal of the grid input circuit, the voltage and current monitoring terminal of the battery pack, and the voltage and current monitoring terminal of the three-phase full-bridge inverter; the control unit passes the signal The signal analysis of the acquisition unit controls the closing and opening of the corresponding contactors and switches, and outputs signals to the single-phase controllable rectifier and the three-phase full-bridge inverter for control.

The invention discloses an electrification oil sample acquisition device for an oil-immersed sleeve pipe of a transformer, comprising an oil conservator of a corrugated metal expansion apparatus, a four-way valve, a sleeve pipe of the transformer and an aciform sample acquisition valve, wherein, the oil conservator of the corrugated metal expansion apparatus is suspended and installed on a fastening bolt on the top of cone of the sleeve pipe of the transformer in a regular way, the four-way valve is arranged on the lower end of the oil conservator of the corrugated metal expansion apparatus, the vertical downward interface of the four-way valve is connected with a connecting pipe by a joint, the connecting pipe is connected with the exhaust hole of the sleeve pipe of the transformer by a through screw, a downward guidance pipe is connected to the lower end of the sleeve pipe of the transformer, and the aciform sample acquisition valve is connected to the other end of the downward guidance pipe. The invention realizes the function of electrification oil sample acquisition of the sleeve pipe of the transformer, realizes the troubleshooting and the maintenance of the sleeve pipe of the transformer under the state of uninterrupted power supply, thoroughly solves the conflict between the scheme of troubleshooting of equipment state and the requirement of periodical power cut for the sample acquisition analysis of the sleeve pipe, achieves the controllability and the under-control of the technical supervision of the equipment, and lays a solid foundation for the high-quality, safe and reliable power supply for the society.

The invention belongs to the technical field of power electronics, and specifically relates to an improved three-phase four-bridge arm topology for realizing active power decoupling used in a system containing a single / three-phase unbalanced load or source. The improved three-phase four-bridge arm topology comprises eight switch tubes S1, S2, S3, S4, S5, S6, S7, S8, four inductors La, Lb, Lc and Ln and five capacitors Ca, Cb, Cc, Cn, Cdc. When the single / three-phase unbalanced load or source exists, a fourth bridge arm is controlled, a passage is provided for a zero-sequence component by usinga center line, and then three-phase phase voltage balance is realized, and high-quality power supply is provided for the load; secondary impulse power on an alternating current side is provided by the capacitors on the alternating current side through active power decoupling control, a direct current side just needs to provide the average power component on the alternating current side, on the basis of without adding switch devices, a secondary impulse power decoupling purpose is realized, the tolerance of supporting capacitors on the direct current side can be reduced effectively, and the influence of secondary impulse power on direct current source or front system control performance is avoided.