203results about How to "Improve power transmission capacity" patented technology

A ball-worm transmission is provided which replaces the sliding friction of the classic worm mechanism with the rolling friction of spherical balls. The ball-worm transmission assembly includes a worm which defines a recirculation path, and a gear coupled to the worm via a plurality of spherical balls. The gear includes a plurality of teeth each having a thickness in a central plane of the gear and a lesser thickness towards both sides of the gear, so that a gap is defined between the teeth is larger towards both sides of the gear than in the central plane of the gear.

A wire includes a plurality of carbon nanotube infused fibers in which the infused carbon nanotubes are aligned parallel to the fiber axes. An electromagnetic shield for a wire includes a plurality of carbon nanotube infused fibers, in which the infused carbon nanotubes are aligned radially about the fiber axes. The plurality of carbon nanotube infused fibers are arranged circumferentially about the wire with the fiber axes parallel to the wire. A self-shielded wire includes 1) a wire that includes a plurality of carbon nanotube infused fibers in which the infused carbon nanotubes are aligned parallel to the fiber axes; and 2) an electromagnetic shield that includes a plurality of carbon nanotube infused fibers in which the carbon nanotubes are aligned radially about the fiber axes. The axes of the carbon nanotube infused fibers of the wire and the carbon nanotube infused fibers of the electromagnetic shield share are parallel.

The invention relates to a method and device for performing on-load scheduling on a single-phase load in the intelligent power grid field. A master controller is mounted at an input end of a three-phase wire, a secondary controller is mounted at each single-phase branch of the wire, and the master controller exchanges information with the secondary controllers through communication interfaces. When the wire power unbalanced degree is over limit, the master controller optimizes and formulates a control scheme to operate the secondary controllers to convert the single-phase load between the phases; in the conversion process, the load is free from instant power off, and the power grid is free from impact and interference; and therefore, the distribution circuit dynamically runs in a load balance state, the unbalanced consumption problem of the circuit is completely solved.

The utility model discloses a control method for optimal operation of reactive power and voltage in distribution network below 10kV, which is characterized in that a distribution network reactive compensating comprehensive control device is arranged on the distribution network to collect the parameters such as voltage, current, active power and reactive power of all nodes in the distribution network and send the parameters to a main control server; at the same time, the main control server receives the parameters such as voltage, current, active power and reactive power of the transformers in the transformer substation transmitted by the reactive optimal server of regional power networks through an SCADA interface server, and conducts reactive voltage optimal calculation, switching the changer through up regulating the main transformer on-load tap changer of the transformer substation or down regulating the distribution network reactive compensating comprehensive control device. The utility model changes the voltage optimal control goal from ensuring a qualified 10kV bus voltage in the transformer station to ensuring a qualified voltage of final user terminals in the distribution network, realizes the optical control of combining distribution network reactive voltage and transmission network, and realizes reactive hierarchical spot balance in the real sense.

The invention belongs to the field of power systems and in particular relates to a method for modulating the active power output of a wind turbine by using an additional damping controller and improving the low-frequency oscillation damping characteristic of a large-scale wind power station grid-connected system. In the invention, according to a basic principle of controlling the optimum rotary speed of a double-fed wind turbine, a low-frequency oscillation characteristic signal of an alternating current power grid after interference is introduced to design the additional damping controller, the additional damping controller outputs a modulation component for controlling the rotary speed of a fan, and adjustment of the active power output of the wind turbine is realized by controlling the rotary speed of the fan, so an effect of restraining system oscillation is achieved. By applying the method to a large-scale grid-connected wind power station, the low-frequency oscillation damping characteristic of the system after interference can be improved; the system oscillation is quickly restrained; and capability of receiving large-capacity new energy source power of a power grid is improved.

The invention provides a multiterminal flexible direct current power transmission system included power grid operation control system and method. The method comprises the following steps of detecting alternating current bus voltage, alternating current bus phase angles and direct current bus voltage of various current converting terminals of a multiterminal flexible direct current power transmission system in real time; when a power grid is failed, and when the power grid is in a transient fault operation mode, performing transient stability operation control on the power grid; when the power grid is in a static fault operation mode, performing static stability operation control on the power grid; and uploading fault information and control information to a control center. According to a power voltage control decision model disclosed by the invention, a control strategy for the static security and stability operation of the multiterminal flexible direct current power transmission network included power grid is carried out, while in the transient fault operation of the power grid, a target function and a boundary condition for the transient stability operation control are established; as a control vector is solved, the corresponding current converting terminals are controlled through the calculated control vector, and thus, the voltage stability of the multiterminal direct current network and the emergency command strategy when the alternating current power grid is in the transient fault operation are effectively realized.

The invention relates to a wire material of an aluminium alloy wire, and a preparation method thereof. An aluminium alloy wire with high strength and high electrical conductivity which has a high fiber texture degree is obtained through an ultra-low temperature rapid drawing process, and the aluminium alloy wire has a fiber texture degree of more than 60%, a tensile strength of more than 130Mpa, and an electrical conductivity of more than 63% IACS. According to the invention, a micro alloying design is performed by using composites of ferrum, scandium and the like which can form Al3Me type eutectic compound particles; a certain fiber texture is obtained through a drawing process by controlling a continuous casting and rolling process; the fiber texture degree is greatly increased and the distortion caused by room temperature deformation is reduced through the ultra-low temperature rapid drawing process; and the texture orientation and the texture degree of the aluminium wire after the drawing process are adjusted through an annealing treatment, the drawing stress is relaxed, the plasticity of the wire is recovered, the resistance of the wire is reduced and the electrical conductivity of the wire is increased. Compared with the prior art, the aluminium alloy wire and the preparation method of the invention can control the deformation process in micro alloying conditions to greatly increase the strength and the electrical conductivity of the wire.

A current regulator includes a first switch, a second switch, a first current detecting circuit, a second current detecting circuit and a control circuit. Both of the first and second current detecting circuits detect the current of corresponding power route. The control circuit controls the first and the second switches on the route to be turned on or turned off according to detecting signals, and regulates to keep the wiring current in balance.

The invention provides a detection method for current-carrying capacity of an overhead conductor. The detection method comprises the following steps of: detecting conductor temperature and environment temperature of the overhead conductor to be detected to acquire at least two groups of conductor temperature values and environment temperature values; calculating a functional relation of conductor current and conductor temperature rise according to the conductor temperature values, the environment temperature values and a current value of the overhead conductor; and calculating maximum current-carrying capacity of the detected overhead conductor at set temperature according to the functional relation. According to the technology, data and equipment to be detected are less, the data operation process is simple, the result reliability is high, the detection cost is greatly reduced while the detection accuracy is guaranteed, the maximum current-carrying capacity of the conductor can be quickly and simply detected in a peak load period, unnecessary power failure is reduced, the power transmission capacity of the overhead conductor is improved, and particularly, the detection method has great significance of popularization to a low-voltage power distribution network.

The invention relates to a method for acquiring a control input signal of a subsynchronous oscillation suppression and control device. In the method, a three-phase AC bus voltage Vabc(t) of an access point of the subsynchronous oscillation suppression and control device serves as an input voltage signal which is converted into two phases of orthogonal static coordinate signals Valpha(t) and Vbeta(t) by Clarke conversion, and a phase error signal Pherr is output after the two phases of orthogonal static coordinate signals pass through a digital phase closed loop link; and a generator set shafting torsional vibration mode signal is separated from the phase error signal by a filtering link as the control input signal of the subsynchronous oscillation suppression and control device. In the method, the bus AC voltage of the access point of the subsynchronous oscillation suppression and control device is adopted as a source signal, and the generator set shafting torsional vibration mode signal is obtained by digital phase locked loop and digital processing technologies, and the reliable control input signal can be provided in situ for a device; and the method is relatively lower in cost and easy to implement.

The invention discloses a risk quantitative assessment method for emergency control measures for improving the power transmission capacity of a power grid and belongs to the technical field of power systems and automation thereof. The method considers the costs of emergency control measures such as generator tripping and load shedding, quantifies the transient stability level of an assessment system in the form of risk indicators, quantifies the risk assessment indicators of the emergency control measures for improving the power transmission capacity of the power grid, combines the system safety and stability with economy and achieves the goal of comprehensively assessing and screening the emergency control measures for improving the power transmission capacity of the power grid. The method is used for assessing and screening the emergency control measures for improving the power transmission capacity in a power system, can realize the risk quantitative assessment of the emergency control measures, and can enable operation personnel to more intuitively know the transient instability risk of the entire system, guide the operation and plan to take corresponding control measures to reduce the transient instability risk of the system and enable the system to operate at levels of higher economy and safety.

The invention belongs to the field of power systems, in particular to a reactive-load compensation equipment application scheme for large-scale wind power delivery system. As for the large-scale wind power delivery system, the invention, aiming to meet the needs of power delivery and wind power access, through reactive power balance analysis in different level years and under different operation modes, provides the capacitive and inductive reactive power demands of each substation in the system, and provides a configuration scheme for low pressure side fixed switching reactive compensation equipment such as capacitors, reactors and the like and dynamic reactive-load compensation equipment such as controllable reactors, static var compensators and the like. The provided configuration scheme can ensure voltage at each point in the system is controlled within a reasonable range under different operation modes, and meanwhile the dynamic reactive-load compensation equipment can meet the requirements of reactive power control of the grid and the voltage under wind power fluctuations with a strong engineering adaptability.

The invention provides a high-strength high-conductivity heatproof copper alloy wire rod and a preparation method thereof. The wire rod comprises the following components: on the basis of weight percentage, 1 to 1.2 of silicon, 0.2 to 0.3 of magnesium, 0.02 to 0.04 of vanadium, 0.01 to 0.02 of titanium, 0.06 to 0.08 of manganese, 0.025 to 0.035 of lutecium and 0.05 to 0.07 of yttrium, with the balance being copper. According to the invention, the component silicon may lead to slight reduction of conductivity, improvement of strength and reduction of toughness, which causes easier fracture of the wire rod in the process of wire drawing; however, the components consisting of magnesium, vanadium and the like are added and a formula and proportions are optimized, so the copper alloy wire rod has high strength and high conductivity.

The invention provides a line commutated converter structure for anti-parallel thyristor-based full bridge submodules (anti-parallel thyristor-based Full bridge submodules, APT-FBSMs). A topology is that each APT-FBSM is connected between each phase of converter and each phase of converter transformer in series; and each APT-FBSM comprises four groups of anti-parallel thyristors and a capacitor. The topological structure can control the capacitor in each APT-FBSM to provide an auxiliary commutating voltage to a converter valve arm in an AC system failure; the system commutating area is increased; and the commutation failure probability of a traditional line commutated converter is effectively lowered. Due to the flexible controllability of each APT-FBSM, an extra harmonic problem is not caused when an AC system normally works; and the problem that the converter loses the self-recover ability due to the fact that each capacitor is continuously charged to an overvoltage when a commutation failure appears can be avoided.

A variable flywheel mechanism is capable of varying the moment of inertia is disclosed. The wheel mechanism includes a sun gear, planetary gears, pivotable arms swung by the planetary gears, and weights mounted on the pivotable arms. The positions of the weights are controlled by rotation of the sun gear.

A wire includes a plurality of carbon nanotube infused fibers in which the infused carbon nanotubes are aligned parallel to the fiber axes. An electromagnetic shield for a wire includes a plurality of carbon nanotube infused fibers, in which the infused carbon nanotubes are aligned radially about the fiber axes. The plurality of carbon nanotube infused fibers are arranged circumferentially about the wire with the fiber axes parallel to the wire. A self-shielded wire includes 1) a wire that includes a plurality of carbon nanotube infused fibers in which the infused carbon nanotubes are aligned parallel to the fiber axes; and 2) an electromagnetic shield that includes a plurality of carbon nanotube infused fibers in which the carbon nanotubes are aligned radially about the fiber axes. The axes of the carbon nanotube infused fibers of the wire and the carbon nanotube infused fibers of the electromagnetic shield share are parallel.

The invention relates to a combined near field communication and wireless power transmitter device comprising a first antenna coupled to antenna tuning network and capable of coupling to one or more second antennae in the near field of the first antenna with coupling characteristics, means for communicating wirelessly using said first antenna with a near field communication device in a near field communication mode, and means for transmitting wirelessly power using said first antenna to another device in the vicinity of the first antenna in a power transmission mode. In power transmission mode, the antenna tuning network operates in resonance and has an initial input impedance which is configured to change if there is a change in the coupling characteristics during power transmission, for example charging. The invention also relates to a method of transmitting power to a mobile device for example for charging purposes.

The invention relates to an alternating-current controllable paralleling reactor comprising a transformer type main reactor and a step reactor. Wherein, the first coil is the main coil which connects the network directly; the second coil is the control coil outside which a break and a thyristor controller are mounted; the third coil is the compensating coil outside which a filtering compensating unit is mounted; and the transformer type main reactor and the second side-connect step reactor are both mounted in a fuel tank to form the body of controllable reactor. The alternating step controllable single-phase paralleling reactor comprises the body with high resistance, the breaker, the thyristor controller and the central controller, and it has the functions and characters which common reactors do not have, including: simply adjusting, rapid response time, non-harmonic-wave, lower noise, lower vibration, high reliability, lower consumption, and it can separate the harmonic wave to reduce the effect to electrified wire netting. The invention can be used in the electrified wire netting of extra-high voltage and long-distance power transmission.

The invention provides a method for optimizing direct current weak receiving terminal power grid static var compensator (SVC) dynamic reactive power compensation configuration measures. The method comprises the following steps that 1, analyzing running characteristics of a direct current weak receiving terminal power grid after direct current is put into operation; 2, analyzing effects of an added SVC on voltage recovery after fault; and 3, analyzing effects of the added SVC on stability characteristics of the power grid. The method for optimizing direct current weak receiving terminal power grid static var compensator (SVC) dynamic reactive power compensation configuration measures aims at actual running to build a complete middle Tibet power grid model. Effects on power grid voltage support capacity and direct current transmission power after an SVC is put into operation are analyzed according to change of a power grid structure and running characteristics. The power grid SVC dynamic reactive power compensation configuration measures are disclosed to improve voltage stability of middle Tibet power grids and to improve electric receiving capacity of the power grids. Effectiveness of the disclosed measures can be verified in a simulation mode.

The invention provides a flexible direct current additional subsynchronous oscillation control system for suppressing subsynchronous resonance and oscillation. The system comprises a feedback signal processor, a multi-mode band-pass filter, a multi-mode proportional phase shifter, a mode control signal synthesizer and an additional signal controller. A subsynchronous damping control strategy is added on a flexible direct current control system, a plurality of torsional vibration modes can be suppressed at the same time, functions are comprehensive, multi-mode subsynchronous resonance and oscillation of a power system can be achieved, subsynchronous stability of the system is improved, transmission capacity of a power grid is further improved, and safety of a generator is ensured.

The invention provides an aluminum alloy conductor for an extra-high voltage. The aluminum alloy conductor for the extra-high voltage comprises the following components in percentage by weight: 0.4-0.7% of Mg, 0.35-0.65% of Si, 0.2-0.4% of Cu, 0.1-0.3% of Fe, 0.05-0.15% of Zn, 0.3-0.6% of B, 0.01-0.1% of Zr, 0.05-0.25% of Y, 0.04-0.2% of Ce, less than or equal to 0.1% of other impurities and elements and the balance being Al; and a preparation method of the aluminum alloy conductor for the extra-high voltage comprises the steps of raw material treatment; smelting; alloying; boronizing; refining; casting; solid solution heat treatment; rolling; drawing; and aging treatment. The aluminum alloy conductor for the extra-high voltage has the tensile strength of 269.27MPa and the electric conductivity of 63% IACS; in addition, the aluminum alloy conductor for the extra-high voltage has the strength survival rate of larger than 93% after being subjected to a test operation, namely heating at the temperature of 300 DEG C for 2 hours.

The invention provides a method for improving the direct current transmission capacity of a direct current fault steady-state voltage constraint. The method comprises steps of step 1, acquiring a direct current transmission power value P1 according to a steady-state voltage fluctuating value deltaV, a safety control generator tripping strategy and a direct current reactive swapping control threshold value of a power grid; step 2, if a direct current sending requirement power P is greater than P1, performing optimization and adjustment on the direct current reactive swapping control threshold value; step 3, acquiring a direct current transmission power value P2 of the power grid with the adjusted direct current reactive swapping control threshold value, and if P is greater than P2, performing combined tripping operation on a no-load circuit and a low voltage capacitor of the power grid; step 4, acquiring a direct current transmission power value P3 of the power grid after being subjected to combined tripping operation, and if P is greater than P3, performing direct current operation according to the direct current transmission power value P3. Compared with the prior art, the method for improving the direct current transmission capacity of the direct current fault steady-state voltage constraint provided by the invention can be used for increasing the electricity generating efficiency of a direct current matched power plant, reducing the short power supply in the peak period in a direct current receiving end area, and greatly improving the extra-high voltage direct current transmission capacity.

The invention discloses a DC traction power supply device comprising a voltage reduction module, an AC / DC conversion module, a voltage distribution module and a DC / DC voltage conversion module which are connected in sequence, wherein the voltage reduction module is connected into a three-phase power supply through a high-voltage circuit breaker for three-phase voltage reduction; the AC / DC conversion module converts AC into DC and carries out power transmission; the voltage distribution module comprises a plurality of voltage distribution units connected in series and carries out series voltage distribution on the DC; the DC / DC voltage conversion module comprises a plurality of DC / DC voltage conversion units connected in parallel; each DC / DC voltage conversion unit is connected to one voltage distribution unit in parallel and carries out DC voltage conversion on distributed voltage output by the voltage distribution unit, and the converted voltage is output to a DC traction power supply system in parallel. The DC traction power supply device is wide in application range and small in work amount, saves cost, achieves DC power supply of the traction system under the condition of not changing an AC traction power supply network structure, and has the advantage of solving the application problems of high input voltage and large output current.

The invention discloses a relay protection configuration method for an overhead-GIL joint line. The method comprises the following steps of (1), mounting a potential transformer and a current transformer at two sides of a GIL; (2), configuring a current differential protection member on the GIL segment; (3), through the current differential protection member configured in the step (2), judging and positioning a fault point through different protection action behaviors; (4), configuring a protection signal communication device on transformer stations at two sides of the overhead-GIL joint line; and (5), configuring a blocking autorecloser of the overhead-GIL joint line. The relay protection configuration method aims at the overhead-GIL joint line; and a PT and a CT are mounted at two sides of the GIL, thereby increasing electric parameters in the line; a self uniform parameter of the GIL line segment is utilized for configuring routine line protection in the GIL segment, thereby realizing high identification accuracy and high fault positioning precision for the GIL fault segment in a relatively easy manner.

The invention discloses a contact aluminium wire continuous annealing method, comprising the following steps of wire drawing, continuous annealing and dual wire collecting. A contact aluminium wire continuous annealing device comprises an aluminium wire large drawing machine, a contact aluminium wire continuous annealer and a dual automatic disc exchanging wire collecting device; the wire feeding end of the contact aluminium wire continuous annealer is connected with the wire output end of the aluminium wire large drawing machine; and the wire output end of the contact aluminium wire continuous annealer is connected with the wire feeding end of the wire collecting device. The contact aluminium wire continuous annealer comprises a power module, a machine shell, at least one wire guiding wheel, at least one drawing wheel, at least one preheating copper contact wheel and at least one annealing copper contact wheel. The aluminium wire produced by adopting the device and the method has the advantages that aluminium wire adhering does not happen after annealing, the softness and hardness of the aluminium wires of the outer layer and the inner layer of the wire coil are consistent, the resistance is consistent, the quality is high, the length is large and the like; the invention can realize assembly line work, save energy, reduce the consumption, and can be widely applied to manufacture electrical wires, electrical cables and large-span overhead aluminium wires which use carbon fiber as a strengthening core.

The invention relates to a series compensation optimization configuration method of a power system circuit, and belongs to the technical field of power system running. The series compensation optimization configuration method comprises the steps of firstly, building a power network mathematical model; secondly, determining a power flow algorithm of a power system; thirdly, adding series compensation to the system circuit, building a multi-target optimization model with minimum system network loss and optimal voltage quality on the basis of power flow calculation by taking series compensation number, a series compensation circuit, series compensation degree and active power output of a power generator as constraint conditions, and optimizing series compensation configuration in the system by employing random weight-based improved particle swarm algorithm to achieve selection of the series compensation configuration number, the series compensation configuration circuit and the series compensation degree under optimal power flow steady state; and finally, performing simulation and solving in Matlab. By the series compensation optimization configuration method, the problem of series compensation configuration of the circuit is solved, the system network loss is reduced, and the system voltage quality is improved; and moreover, with the adoption of the random weight-based improved particle swarm algorithm, the optimal solution of the system is ensured, and local optimization is prevented.

The invention relates to a call wire random power fluctuation calculating method based on a load fluctuation characteristic. First, a correlation model of load fluctuation and call wire random power fluctuation is established, the correlation model of load fluctuation and call wire random power fluctuation is deduced and analyzed in a detailed mode according to dynamic differential analysis of call wire power fluctuation, system frequency response analysis, call wire power fluctuation analysis based on system frequency analysis and call wire fluctuation analysis based on the load fluctuation characteristic. Two zone frequency response coefficients and corresponding weight coefficients are acquired, two zone load distributions f (x) and f (y) are acquired according to practical operation data, Monte Carlo sampling simulating test is carried out according to the distributions, results are subjected to statistics and analysis, and then call wire random power fluctuation conditions are calculated. The method is high in reliability, accurate and efficient, and powerful support can be provided for quick restraining of call wire random power fluctuation and improving of call wire electricity transmission capacity.

The invention discloses a molten-salt single-tank electric heating heat storage heating system and a using method. The molten-salt single-tank electric heating heat storage heating system comprises amolten salt heat storage tank; a high-temperature molten salt inlet is formed in the upper portion of the molten salt heat storage tank, and a low-temperature molten salt inlet is formed in the lowerportion of the molten salt heat storage tank; a low-temperature molten salt pump and a high-temperature molten salt pump are arranged on the molten salt heat storage tank; an outlet of the low-temperature molten salt pump is connected with a molten salt inlet of a molten salt electric heater, an outlet of the molten salt electric heater is connected with the low-temperature molten salt inlet and amolten salt side inlet of a heat exchanger, and the molten salt electric heater is connected with a power supply; an outlet of the high-temperature molten salt pump is connected with the molten saltside inlet of the heat exchanger, a molten salt side outlet of the heat exchanger is connected with the low-temperature molten salt inlet, and the water side of the heat exchanger is connected with aheat consumer. According to the molten-salt single-tank electric heating heat storage heating system and the using method, molten salt is adopted as a heat storage and heat release medium and is poisonless, harmless, cheap and easy to obtain; heat storage is conducted through off-peak electricity and waste electricity not using wind and light, therefore, the peak and off-peak difference of a powergrid can be significantly decreased, the actual running efficiency of a coal-fired power unit is improved, the power transmission capability of the power grid is enhanced, and the renewable energy source utilization efficiency is improved.