600 results about "Single-phase electric power" patented technology

The invention relates to a current forecasting dead-beat control method of a Z source type interconnected inverter and a control device thereof, which belongs to the field of electrical energy conversion and is used for interconnected power generation. The current forecasting dead-beat control method overcomes the defect of sampling delay of the conventional control method. In each sampling period, a robust prediction algorithm is adopted to forecast interconnected current of the next period, and the needed inverted voltage is calculated according to a voltage equation of the inverter to realize the deadbeat control of the interconnected current. A single-voltage space vector modulating method with a through zero vector is used for generating a through-state pulse-width modulation wave shapes of the inverted voltage to control the DC capacitance voltage and the interconnected inverted voltage. The control device comprises a central processing unit, a synchronous signal generating circuit, a voltage and current testing circuit and an isolated driving circuit. The current forecasting dead-beat control method of the Z source type interconnected inverter has high control precision, is easy to digitally realize, has stronger inverted-side inductance parameter variation robustness, and the like.

The invention relates to a method for checking electricity stealing based on remote calibration for a grid line running error. The method specifically comprises the steps of (1) dividing detection subareas, additionally arranging new electric energy measurement equipment in the subareas, and improving the digital resolution of all electric energy measurement data; (2) installing a detachable single-phase electric energy meter for each detection subarea to serve as an error standard for error detection; (3) acquiring all electric energy data of the detection subareas, and substituting the datainto an electric energy data error calculation model; (4) taking the 2-3 detachable single-phase electric energy meters installed in the detection subareas back to a laboratory, and checking the accuracy of the calculation result; and (5) calculating 10KV user electricity stealing conditions in a distribution network according to the calculation result. According to the method, the loss of a powersupply line can be accurately measured and monitored in real time, power interruption is not required, measurement for an error of all electric energy measurement devices within a 10kV distribution network is realized, loss detection and real-time monitoring for transmission lines of the distribution network can be achieved, and thus an electricity stealing line can be tracked and checked quicklyand accurately.

A node within a wireless mesh network is configured to record a zero crossing of alternating current or alternating voltage drawn by a single-phase power consumer and a precise timestamp when the zero crossing occurred, thereby generating timestamped zero crossing data. The node receives similar zero crossing data from a neighboring node. The node then compares the timestamped zero crossing data with the received zero crossing data to determine whether the phase associated with the node is equivalent to, leads, or lags the phase associated with the neighboring node. The node then acquires a positive phase identification associated with the neighboring node. Based on the phase identification, and based on the phase difference between the two nodes, the node infers the phase associated with the single-phase power consumer. That phase indicates the specific power line within a three-phase power distribution network to which the single-phase power consumer is coupled.

The invention provides a flexible island grid-connection control device and method for smart power grids. The device comprises flexible inversion units, single-phase electric power detection units, GPS phase detection units, an island grid-connection detection unit, a communication unit and a master control unit. Each flexible inversion unit comprises an angle form differential voltage topological circuit and a star connection type inverter circuit. Each single-phase electric power detection unit is connected with the output end of the corresponding star connection type inverter circuit and a PCC nodal point. Each GPS phase detection unit is connected to the output end of the corresponding star connection type inverter circuit and a PCC nodal point. The input end of the island grid-connection detection unit is connected to the output ends of the single-phase electric power detection units at the PCC nodal points and the output ends of the GPS phase detection units at the PCC nodal points. The output end of the island grid-connection detection unit is connected with the input end of the master control unit. According to the flexible island grid-connection control device, the flexible inversion units composed of novel topological structures can make a micro power grid and a main power grid conduct flexible grid-connection and conduct switching of islanding modes, so that impact of the micro power grid on the circuits is reduced.

An enclosure or shelter having an interior chamber for housing electronic components and equipment is provided with an HVAC / R system configured with a rechargeable DC power source for power back-up to maintain substantially uninterrupted power in the case of a main power failure. The system includes one or more variable frequency drives (VFD) controlled by a VFD controller and configured to provide three-phase power to one or more three-phase AC motors and single-phase power to one or more single-phase AC motors. The system also includes a power source controller configured to select and power sources based on availability of one or more power sources and other logic.

The invention discloses a single-phase PWM rectifier dynamic performance optimization control method based on active disturbance rejection control. The method adopts double closed-loop control of a voltage outer loop and a current inner loop, the current inner loop adopts single-phase DQ current decoupling control and the voltage outer loop adopts active disturbance rejection control. In particular, according to the principle of power conservation, a mathematical model for active DC components isd of single-phase PWM rectifier output DC voltage udc and grid-side AC voltage is deduced; and according to the mathematical model, a voltage outer loop active disturbance rejection controller is designed. In comparison with the traditional single-phase DQ current decoupling control voltage outer loop adopting PI control, the voltage outer loop in the invention adopts active disturbance rejection control, and while grid-side unit power factor operation and DC-side voltage stable control are realized, the dynamic response speed of the system is better and the anti-interference ability is stronger.

The invention relates to a power spring application system based on power control and a control method thereof. The power spring application system comprises a conventional power generation output voltage source vG, a line resistor R1, a line inductor L1, a key load ZC, a non-key load ZNC, a single-phase power spring system and an analog new energy power generation grid-connected inverter system. Aiming at the problem of voltage and power fluctuation of a micro grid, which are caused by instability of output power of new energy power generation, the invention discloses the power spring application system based on power control and a control technology thereof, so that fluctuation of the new energy power generation voltage and power can be transferred to a power spring device and the non-key load, thereby ensuring stability of the voltage and the power on the key load. The power spring application system and the control method thereof, which are disclosed by the invention, are high in practical value, easy to popularize; in a place where the key load is positioned, stability of the voltage and the power of such key load can be effectively kept, so that electric energy quality of the key load is improved.

The invention relates to a two-way single-mode ramp type tower-shaped linear ultrasonic motor and an electric excitation method thereof, and the two-way single-mode ramp type tower-shaped linear ultrasonic motor belongs to the ultrasonic motors and comprises a stator, piezoelectric ceramics and a guide rail. The guide rail is pressed on a stator drive foot by pre-pressure and inclines with a Theta angle. The stator comprises the drive foot, a flexible amplifying round hole and a tower-shaped metal body of two rectangular columns, and six piezoelectric ceramics are symmetrically adhered on the outer surface of the tower-shaped metal body and used for exciting two orthogonal working modes (x-z section bending vibration mode and y-z section symmetrical vibration mode including local bending vibration) of the stator. When a single-phase voltage signal is used for exciting any one working mode of the stator, a motion curve of mass points on the surface of the stator drive foot is a skew line oppositely to the guide rail, and the skew direction of the skew line is changed with the change of the working modes, thereby pushing the guide rail to move in a forward and reverse way. The ultrasonic motor has compact structure, high drive efficiency, large thrust-weight ratio and reliable working.

The invention provides dynamic simulation device and method thereof of a super and extra high voltage controllable magnetic control shunt reactor, wherein the dynamic simulation device is capable of accurately simulating magnetic control shunt reactors with different capacities in 500kV, 750kV and 1,000kV power transmission systems. A simulation body consists of three single-phase magnetic control reactors; each single-phase magnetic control reactor is in a three-column structure; two beside core columns are working iron cores; a main alternating current winding and a direct current control coil are wound on each working iron core; and main alternating current windings on the two iron core columns are connected in parallel and connected to a power grid. Control windings are separated from the main windings so as to ensure the safety and the reliability of the device during work. The main windings are provided with twelve turn-to-turn short circuit taps which can respectively simulate 1-25 percent of turn-to-turn short circuit faults from the high-voltage side and the neutral point side; and the control windings are provided with seven turn-to-turn short circuit taps which can simulate 1-25 percent of turn-to-turn short circuit faults from the neutral point side. The body of the device is provided with a current transformer and a voltage transformer on a primary side, which are used for meeting the requirement for protecting a reactor body in a dynamic simulation test.

A three-phase winding Y junction single-phase capacitor run motor is provided, wherein the rated output power is 40-250W, the rated slip ratio is 0.12+ / -0.03; the stator core punching sheet is in the square round figuration with the square size 108+ / -1mm and four angles inversed with arc, the 24-slot is in equal tooth width, and the four arc sections are arranged with four slots, wherein four straight segments are all arranged with two shallow slot respectively; the stator fillet is in the three-phase four-pole, single layer, the pitch is five, and the first phase is distributed in the shallow slot while the second phase and the third phase are distributed in the deep slot; the effective turn of the second phase and the third phase is 1; the bottom of the three-phase winding is connected together, and the starting end of the second phase and the third phase windings is connected with a capacitor; one of the starting end of the second phase and the third phase windings is connected wit a single-phase power, characterized in that, the effective turn of the first phase and the second phase is 0.3+ / -0.1. According to the turn ratio, the motor can better compromise the product standard about the starting and the operating performance, and obtain better performance.

The invention relates to the field of intelligent meter reading technology, and discloses a transformer district identification system and a transformer district identification method thereof, thereby realizing transformer district identification by means of an existing equipment resource. The system comprises a concentrator and a user meter based on carrier communication, and a transformer district identification instruction in communication connection with the concentrator. The transformer district identification instrument comprises a power supply conversion module which is connected with single-phase power of a transformer end, wherein the power supply output end of the power supply conversion module is connected with a carrier module and a master control unit. A master control chip is connected with a zero-crossing detecting circuit and a pulse excitation generating circuit. Furthermore the zero-crossing detecting circuit and the pulse excitation generating circuit are respectively with phase wires, so that the master control chip triggers the pulse excitation generating circuit to generate a pulse excitation signal for outputting to a corresponding bus when the zero-crossing detecting circuit detects zero crossing of AC power of a corresponding bus after the master control chip receives a transformer district identification instruction that is broadcast by the concentrator through the carrier module.

The invention provides a dual-buck type half-bridge parallel active power filter, belonging to the technical field of power harmonic suppression. The dual-buck type half-bridge parallel active power filter respectively comprises two types of power filter structures used for a single-phase power grid system and a three-phase four-wire system power grid system, and further comprises a bridge arm unit formed by connecting a power tube and a diode in series, parallel double inductors on an active power filter AC (Alternating Current) side, and serial double capacitors on an active power filter DC (Direct Current) side. The invention not only has the advantages of simple structure and easy control, but also can avoid the danger of the shoot-through bridge arm, simultaneously has an excellent filtering property, and can be widely applied to aviation, spaceflight, military equipment manufacture and other industries with high requirements on power supply quality of a power grid and system reliability.

The invention discloses a damping pad for weakening noises of a unit by tangential vibration of an isolation motor and a single-phase motor mounting structure using the damping pad. A pad body of the damping pad comprises a vibration isolating section, a first damping section and a second damping section, wherein the vibration isolating section is positioned at the middle of the pad body; the first damping section and the second damping section are respectively positioned at two ends of the vibration isolating section; the inside diameter of the vibration isolating section is greater than the inside diameters of two damping sections; an annular groove is formed in the outer circumference of the vibration isolating section; and the width of the annular groove is not greater than the length of the vibration isolating section. The single-phase motor mounting structure comprises connecting bolts and fasteners matched with the connecting bolts; the connecting bolts are used for fixing the damping pad and motor support legs with mounting holes to a mounting foundation; the mounting holes of the motor support legs are in clamped fit with the annular groove on the damping pad; through holes of the damping pad are in clearance fit with the connecting bolts; and in a fastening state, the damping pad has a movable clearance delta in the axial direction. According to the single-phase motor mounting structure, various vibrations of the single-phase motor can be effectively reduced and operation noises are reduced; and the single-phase motor mounting structure can be applied to various household electrical appliance products.

The invention discloses a linear approximation method for a border of static voltage stability domain of an electric power system, relating to the field of the border of the static voltage stability domains. The method comprises the following steps: searching a first electric power system saddle node bifurcation point through a traditional optimal power flow by taking a base power flow as an initial point, and mapping the first electric power system saddle node bifurcation point to a two-dimensional active injection space, so as to obtain the border of the static voltage stability domain; changing a power increase direction towards an increase direction of a power increase direction angle, and calculating a electric power system saddle node bifurcation point in the new power increase direction by virtue of a Lagrangian multiplier method; and ending the calculation when the power increase direction angle is smaller than or equal to 0: carrying out linear approximation on all obtained border points of the static voltage stability domain by virtue of a subsection approximation method, so as to obtain the approximated border of the static voltage stability domain. According to the linear approximation method, the obtained static voltage stability domain preserves relatively high precision, the time consumed for searching single electric power system saddle node bifurcation point byvirtue of the traditional optimal power flow is effectively shortened, and the practical application value for analyzing the stability by virtue of the static voltage stability domain is increased.

The invention relates to a single-phase multi-parameter electric power instrument which can provide a measuring instrument for a single-phase electric power parameter to realize the mensuration of a single parameter or multi-parameter of current, voltage, power factors, active power, reactive power and the like. The instrument comprises a sampling circuit, an electric power measuring circuit, a microprocessing singlechip circuit, a display circuit and a power supply circuit; the sampling circuit is connected with a voltage signal and a current signal; the electric power measuring circuit is connected with the sampling circuit and the microprocessing singlechip circuit; the display circuit is connected with the microprocessing singlechip circuit; and the power supply circuit provides power. The single-phase multi-parameter electric power instrument has the advantages that as the instrument adopts the electric power measuring circuit and the microprocessing singlechip circuit, the instrument has high testing precision and more measuring parameters; and the instrument adopts the mature chip in order to have small power consumption and be suitable for batch production.

The control circuit of three-level output single-phase Boost PFC circuit with both commercial power input PFC function and battery step-up function includes input voltage sampling part, output voltage sampling part and control loop part. The input voltage sampling part includes battery input voltage signal sample circuit to convert battery voltage into signal BATTSN, commercial power input voltage signal sample circuit to convert the commercial power input voltage into signal ACSN, selecting circuit to feed the signal BATTSN to ACSN to subsequent effective value filter circuit with the gated signal being also used as the current following signal as control loop input, and effective value filter circuit to filter the signal BATTSN or ACSN or obtain the effective value signal for the control of the loop. The present invention is easy to design and debug.

The invention relates to an isolated serial peripheral interface (SPI) bus electric energy measuring module and an APLC electricity meter. The isolated SPI bus electric energy measuring module consists of a tensile transient overvoltage electric quantity input circuit, a single-phase electricity measuring circuit, an SPI optical isolation interface circuit and a first voltage stabilizing circuit, wherein a shunt, a sampling current access circuit, a high-voltage isolation voltage transformer T and a symmetrical resistance bridge RE partial pressure sampling circuit are arranged in the tensile transient overvoltage electric quantity input circuit; the shunt is used for sampling the phase line current; the sampling current is filtered and is input into the single-phase electricity measuring circuit through the sampling current access circuit; the high-voltage isolation voltage transformer serves as a phase voltage or a line voltage for sampling and serves as the first voltage stabilizing circuit for supplying power; and alternating voltage at two ends of a secondary coil of the high-voltage isolation voltage transformer T is input into the input end of the symmetrical resistance bridge RE through resistance.

The invention discloses an electric heating control system based on power line carrier communication and a working method. The electric heating control system comprises a meter and a plurality of temperature controllers connected in parallel on a power line. On a single-phase power line, the meter performs data management and control on the temperature controllers connected in parallel on the single-phase power line through a power line carrier module. On a multi-phase power line, the meter is connected to a connecting line of each temperature controller and each phase of the power line, and the meter performs data management and control on the temperature controllers connected in parallel on each phase of the power line through the power line carrier module. Data management and control comprise measures of inquiring the target temperature controller which is most suitable for starting and stopping according to the data coupled on the power line and starting or stopping heating of heating equipment connected to the corresponding temperature controller. Power line carrier communication is used in the electric heating control system, so that the defects that wired control needs independent wiring and wireless control is poor in signal are overcome, construction is greatly facilitated, conflicts of wireless signals is avoided, and radiation is reduced.

A connector assembly mechanically and electrically connects a shielded power cable, capable of conducting DC and multiple phase AC electric power, to drive motors and powered accessories of an electric vehicle. The connector assembly includes a shielded power cable, a connector body, a sealing ring, a tapered compression ring and a flexible rubber boot. The hollow frustoconical interior of the connector body and the frustoconical tapered compression ring, with the shield layer of the power cable compressed between them, form a self-locking taper that provides a strong mechanical connection. The sealing ring and the flexible rubber boot inhibit penetration of fluids and particles into the connector assembly. The addition of an adhesive to the compressed section strengthens the connection and reduces corrosion. Filling empty spaces inside the connector body with an adhesive sealer further prevents penetration by contaminants, reduces corrosion and strengthens the connector.

The invention relates to distribution of electrical power, supervision and security. The invention comprises a power feeding station PFS for delivering electrical power. The PFS comprises a low voltage side LVS, a high voltage side HVS and a transformer TF which is configured to deliver high voltage single phase alternating current on the high voltage side, The power can be distributed, via a cable, to one or more power receiving stations PRS. The cable is configured to distribute current-symmetrical single phase current delivered by the power feeding station. The cable can preferable be a coaxial cable with the shield as current return path. The invention also comprises a current sensor unit CSU which is situated on the high voltage side. The means for measuring characteristics of the current CD can comprise a coil without galvanic contact with the high voltage side. A circuit break unit CBU suitable for breaking the current is situated on the low voltage side. A control function CF is configured to activate the circuit break unit based on the safety rules and the characteristics of the current CD. Characteristics of the current and other system information SI can also be delivered to an information unit IU.

The invention relates to a set of AC phase-changing transformer capable of changing phase number and changing voltage, and a power transmission method of the transformer. The transformer suitable for three-phase and two-phase AC power transmission is characterized in that the transformer can transmit power in a single-phase single-line and grounded manner at the high-voltage side; and the transformer at the power consuming end is also provided with an exciter besides a single-phase winding at the primary side. The transformer is simple, convenient and effective in changing a single-phase power to a three-phase or two-phase AC power meeting the power requirement, thereby relatively lowering the cost for suspending power transmission lines and the facility cost. In addition, the number of windings of the transformer is reduced by obviating phase-to-phase voltage so as to facilitate insulation of the transformer. Accordingly, the transformer provided by the invention is beneficial to improvement on transmission voltage and reduction of cross section area of power transmission wires.

This invention relates to a supply device including: the input lines of a three-phase supply N, L1, L2 and L3, output line of a single-phase supply n, 1, a voltage processor, main relays J1, J2, J3, J4, J5, J6 asnd J7 and voltage mutual-inductors V1, V2, V3, V4, V5 and V6. This simple structure can provide most suitable supply to single-phase supply applicances, which either guarantees their normal use in the region net or automatically balances the three-phase supply net and provides the ideal supply condition for single-phase supply applicances to guarantee power devices and supply applicances to operate efficiently and selects three-phase voltages to be used for single supply when the net is at the super-low voltage.

A controller is provided for transitioning a drive signal to a single phase motor between a square wave and pulse width modulation modes, wherein the drive signal is in square wave mode at low motor frequencies and in pulse width modulation mode during normal operation. The transitioning includes using a real time motor model to effectuate transition of the drive signal between the modes, and a sampling rate for sampling the real time motor model during the transitioning. The sampling rate is automatically modified during the transitioning, wherein acceleration of the motor includes transitioning the drive signal from square wave mode to pulse width modulation mode, including periodically increasing the sampling rate during the transitioning. Conversely, when transitioning from pulse width modulation mode to square wave mode, the controller automatically deaccelerates the sampling rate during the transitioning.

An output current feedback type active electric power filtering method with DC source is characterized by that the serially connected equivalent impedance has positive resistance characteristics and the gain coefficient is used to control the value of equivalent impedance, so decreasing the ripple voltage and ripple current of output. Its system is characterized by that a current transformer is mounted to output of said filter, and the detected current signal passes through band-pass filter, gain amplifier, PWM and pulse driver to control the single-phase voltage inverter, whose output voltage pulse passes through coupling transformer, smoothing reactor and passive filter to suppress the ripples.

A matrix converter includes first to third AC reactors (L1, L2, L3) connected in series with first- to third-phase outputs of three-phase AC electric power (11), and a first cooling fan (17) that generates cool air for cooling the first to third AC reactors (L1, L2, L3). The first to third AC reactors (L1, L2, L3) are arranged side-by-side in a direction intersecting a direction in which the cool air flows.

The invention discloses a single-phase electronic type keyboard prepayment meter which comprises an SOC interface circuit, a power supply circuit and a power failure detection circuit. The power failure detection circuit detects a direct current power source output by the power supply circuit. When the situation that the voltage of the direct current output by power supply circuit is larger than or equal to a preset voltage threshold valve is detected by the power failure detection circuit, the power failure detection circuit outputs a connecting signal to the SOC interface circuit, the SOC interface circuit operates normally. When the situation that the voltage of the direct current output by power supply circuit is smaller than or equal to the preset voltage threshold valve is detected by the power failure detection circuit, the power failure detection circuit outputs an interrupt signal to the SOC interface circuit, and the SOC interface circuit executes power failure data storage action. According to the single-phase electronic type keyboard prepayment meter, the power failure detection circuit can accurately detect the magnitude of the direct current output by the power supply circuit, and the reliability of the operation of the single-phase electronic type keyboard prepayment meter is guaranteed.

The invention discloses a signal acquisition device and a signal processing method for an alternating current power current-sharing output system, and belongs to the field of alternating current power current-sharing output. The signal acquisition device performs current and voltage acquisition on each single-phase power supply of an alternating current power supply and a current-sharing power supply to obtain accurate signals, so that the current-sharing control accuracy of a microprocessor for the current-sharing power supply is improved. By the signal processing method, the amplitude, frequency and phase of each single-phase power supply in the alternating current power supply and the current-sharing power supply can be accurately detected, so that the current-sharing control accuracy of the microprocessor for the alternating current power supply is further improved, and a load is prevented from being burnt down.