89results about How to "Increase active power" patented technology

The invention belongs to the technical field of wind power generation, and discloses a comprehensive control system adopting a doubly-fed wind generator participated in power grid primary frequency modulation. The control system comprises a rotor rotary speed control module, a simulation inertia control module, a droop control module, a rotary speed protection and power determination module and apitch angle control module. After the wind generator is participated in frequency modulation, the power grid inertia is equivalently enlarged, so that the doubly-fed asynchronous wind generator can have inertia response on the power grid frequent as the conventional synchronous generator, thereby lowering change rate of the power grid frequency; and by controlling the rotary speed and the pitch angle, the wind generator output is lowered, so that the wind generator has certain active backup capacity to be participated in primary frequency modulation, thereby lowering steady-state error of thefrequency.

The invention relates to a heat pump type clothes dryer which comprises a control system, a refrigeration system and an air circulation system, wherein the refrigeration system consists of a compressor, a condenser, an evaporator and a throttle valve, the air circulation system consists of a clothes drying barrel, an evaporator, an evaporator fan, a condenser, a condenser fan, a humid heat air flow passage, a low-temperature dry air flow passage and a dry air flow passage, the humid heat air flow passage is arranged between the clothes drying barrel and the evaporator, the low-temperature dry air flow passage is arranged between the evaporator and the condenser, the dry air flow passage is arranged between the condenser and the clothes drying barrel, the compressor is a variable-frequency compressor and comprise a first condenser and a second condenser group which are connected in series, and the output end of the first condenser is also provided with a by-pass pipeline so that refrigerants can selectively flow to the throttle valve through the by-pass pipeline. The heat pump type clothes dryer can be used for high temperature dehumidification in high moisture content, can be used for medium temperature dehumidification in low moisture content and has obvious energy saving effect.

The invention provides an adaptive tuning device and tuning method of emission end of a wireless electric power transmission device. An alternating current power supply, a rectification filtering circuit, a high-frequency inversion circuit, a voltage detection device, an LC adjustable network, a compensation capacitor CP, an emission coil LP, an emission end impedance RP and a current detection device are successively connected together. A controller receives current and output of the current detection device and calculates and controls the high-frequency inversion circuit and the LC adjustable network. Two full-controlled devices M1 and M2 are serially connected with diodes D1 and D2, then are reversely parallelly connected with each, then are serially connected with a fixed inductor LT and then are parallelly connected with a power common capacitor CT, so a phase-controlled inductor capacitor parallel circuit is formed. S1 and S2 are square waves for the LC control circuit to controlon and off the M1 and M2. According to the invention, stability of the energy transmission system can be improved; and defects that the current wireless energy transmission system is easily detuned and an emission device fails to transmit energy to various kinds of receiving ends are solved.

The invention provides an identifying method and a device of abnormal pitch change of a wind turbine generator system. The method comprises the steps of: obtaining a pitch angle signal of each blade; and determining if the abnormal pitch change occurs according to the pitch angle signal of each blade, wherein the abnormal pitch change comprises the pitch angle jump or the pitch angle desynchrony. The method can quickly identify the abnormal pitch change state, in particular the pitch angle jump or the pitch angle desynchrony when the wind turbine generator system is located in the abnormal pitch change state before the pitch change failure, so that the abnormal pitch change state can be timely treated, the damage of such key parts as a pitch change motor is effectively prevented, and the active power output by the wind turbine generator system is effectively improved.

Controlling a wind turbine during a grid fault where the grid voltage drops below a nominal grid voltage. After detection of a grid fault, the total current limit for the power converter output is increased to a total maximum overload current limit. Depending on whether active or reactive current generation is prioritized, an active or reactive current reference is determined. The active current reference is determined in a way so that a reduction in active power production due to the grid voltage drop is minimized and based on the condition that the vector-sum of the active output current and the reactive output current is limited according to the total maximum overload current limit, and a maximum period of time is determined in which the power converter can be controlled based on the active/reactive current references. Afterwards the power converter is controlled based on the active and reactive current references.

The present invention discloses a dynamically tuning device and a tuning method for the sending terminal of a wireless electric energy transmission device, and relates to the technical field of wireless electric energy transmission. The primary side of the dynamically tuning device is provided with a phase detection device PD, a BUCK circuit, a control unit CU and a rectifier bridge. According to the detected phase difference state, the resonant state is judged. Meanwhile, the real-time tuning is realized through adjusting the equivalent output resistance of the BUCK circuit. As a result, the primary side can be maintained to run at a minimum voltage phase difference and a minimum current phase difference. That means, a primary side circuit is closer to the completely resonant state, so that the active power of the sending terminal is improved. Furthermore, the transmission power and the transmission efficiency of the wireless electric energy transmission device are improved.

The embodiment of the invention provides an identification method and device for the wind-generating-set variable pitch abnormality. Blade operating parameter signals of a wind generating set are obtained; the operating parameter signals are subjected to fast fourier transformation; the frequency-domain characteristic quantity of the operating parameter signals after fast fourier transformation isextracted; whether the variable pitch abnormality occurs or not is determined according to the frequency-domain characteristic quantity, and according to the frequency-domain characteristics of the operating parameter signals of blades with the variable pitch abnormality, before variable pitch faults of the wind generating set occur, and when the wind generating set is in the variable pitch abnormal state, the variable pitch abnormal state can be rapidly identified, the variable pitch abnormal state can be thus eliminated, damage to key parts such as a variable pitch motor is effectively prevented, and the active power output by the wind generating set is effectively improved.

A method for stabilizing particulate peroxycarboxylic acids, in particular imidoperoxycarboxylic acids, (such as, e.g., PAP), which are solid at an ambient temperature in a preferably aqueous dispersion containing surfactants. The dispersion is established in such a way that in the dispersed state a degradation of the peroxycarboxylic acids in the dispersion is prevented or at least reduced or retarded, or that the solubility of the peroxycarboxylic acids in the dispersion is diminished, in particular by minimizing the halide ion content, reducing the pH value to pH values ≦7, minimizing the content of free or active surfactants, minimizing the content of non-ionic surfactants, adding complexers, adding catalases or adding a solvent with a low solubility capability for peroxycarboxylic acids etc.

The invention discloses a control system and method of a direct current load system in response to a frequency modulation requirement of a power grid in a manner of intervals. The system comprises a main circuit system and a control system, the main circuit system comprises a rectification module, a DC/DC module and a direct current load, the control system comprises rectifier control, DC/DC control and direct current voltage droop control, the system performs frequency modulation in the manner of intervals through voltage droop control of the direct current load, and the work mode comprises five operation modes including constant-voltage operation, boosted frequency modulation, voltage-reduction frequency modulation, under-voltage protection and overvoltage protection. According to the system and method, the terminal voltage of the direct current load and the frequency of the power grid are coupled, a rectifier load participates in a frequency modulation process of the power grid as much as possible in the condition of satisfying safe operation and basic operating requirements so that the stability of the power grid can be improved, the control method is simple, the circuit structure is clear, the operation is flexible, the response is rapid, and the application value is good.

The invention provides an energy-feedback type traction power supply device with low harmonic waves and high output power and a control method of the energy-feedback type traction power supply device. The power supply device comprises a phase-shifting transformer, a PWM rectifier unit and a control unit. A primary side three-phase winding of the phase-shifting transformer is in star connection. Two secondary side three-phase windings of the phase-shifting transformer are respectively in delta connection and in star connection. The primary side three-phase winding of the phase-shifting transformer is used for being connected with an AC power supply. The two secondary side three-phase windings of the phase-shifting transformer are connected with an AC side of the PWM rectifier unit. The control unit is connected with the PWM rectifier unit. The control unit controls the PWM rectifier unit through a fixed amplitude vector in an SHEPWM mode. Through the energy-feedback type traction power supply device with the low harmonic waves and the high output power and the control method of the energy-feedback type traction power supply device, active power outputted by the PWM rectifier unit can be improved, and current harmonics can be reduced.

The invention discloses a copper tube and an electric furnace energy-saving noninductive short net, wherein the copper tube comprises a first conductor and a second conductor axially sleeved on the periphery of the first conductor; a first insulation layer is filled between the first conductor and the second conductor; and the electric furnace energy-saving noninductive short net comprises a plurality of parallel conductive pipe fittings, each conductive pipe fitting comprises the first conductor and the second conductor axially sleeved on the periphery of the first conductor; and the first insulation layer is filled between each first conductor and the corresponding second conductor. By means of the electric furnace energy-saving noninductive short net provided by the invention, the defects of high inductive reactance, high impedance, low natural power factor, high unit power consumption and the like in the prior art are overcome, and the advantages of low inductive reactance, low impedance, high natural power factor and low unit power consumption are realized.

The embodiment of the invention provides a method and device for recognizing variable pitch abnormities of a wind generating set. The method comprises the steps that a variable pitch speed signal of the wind generating set is obtained; and whether the variable pitch abnormities occur or not is determined according to the variable pitch speed signal, wherein the variable pitch abnormities comprise the variable pitch speed pinion abnormity or the variable pitch speed peak abnormity. When the wind generating set is in a variable pitch abnormity state before a variable pitch failure occurs, the variable pitch abnormity state, especially the variable pitch speed pinion abnormity or the variable pitch speed peak abnormity, can be quickly recognized, then the variable pitch abnormity state can be handled in time, key components like a variable pitch motor are effectively prevented from being damaged, and the active power output by the wind generating unit is effectively improved.

The invention discloses a preparation method and device for artificial crystal synthetic mica. The method and device provided by the invention provide reliable guarantee for obtaining high-quality synthetic mica. In addition to being used as synthetic mica, each component in the raw material for preparing synthetic mica provided by the invention also has the function of removing impurities in the raw material, which lays a good foundation for forming synthetic mica and obtains high-quality synthetic mica.

The embodiment of the invention discloses a motor control device and method. The motor control device comprises a driving circuit for obtaining a three-phase output voltage according to an input voltage command and a stator angle to drive a motor; and an adjusting circuit for obtaining an advance angle according to a phase current signal flowing through the motor and a back EMF angle, and adjusting a stator angle according to the advance angle so that the phase current signal and the back EMF signal can automatically achieve in-phase change, thereby achieving the advance angle control in a wide working range.

The invention discloses a photovoltaic power generation split-phase control method for a power supply system, and the method comprises the steps: collecting three-phase voltage and three-phase currentinstantaneous values of a photovoltaic inverter, and obtaining the active power and reactive power of the photovoltaic inverter through phase voltage and phase current injection into a traction sidethrough calculation; determining an output strategy of the photovoltaic inverter based on the voltage and current relationship between the traction side and a photovoltaic low-voltage side and the locomotive load state of the traction side, and generating a three-phase current per unit value injected into the traction side; and based on the output strategy and the three-phase current per unit value injected into the traction side, controlling the output current of each phase current of the photovoltaic inverter to track the three-phase current per unit value so as to complete power supply to atraction side load. According to the method, the intuition, rapidity and stability of a traction side photovoltaic inverter system are improved. The invention further discloses a photovoltaic traction power supply system, the three-phase photovoltaic power generation system can be directly connected into a three-phase power system, and unbalanced current, reactive circulation and oscillation power, caused by a single-phase transformer, of the three-phase system are avoided.

The invention discloses a dynamic tuning method for transmitting terminal frequency tracking of wireless electric energy transmission equipment. According to the invention, the resonant frequency of a transmitting terminal circuit is tracked dynamically by using a principle that the ratio between a current effective value of a transmitting coil and a transmitting terminal DC-side power supply current effective value is the minimum during resonance of the transmitting terminal circuit, that is, the ratio between the current effective value of the transmitting coil and the transmitting terminal DC-side power supply current effective value is tracked through continuously tuning the operating frequency of an inverter, and the current ratio is enabled to dynamically stay at the minimum value in real time, so that dynamic tuning for frequency tracking is realized, and the transmitting terminal circuit is enabled to stay at or approach to a state of complete resonance, thereby improving the transmission power and the transmission efficiency of the wireless electric energy transmission equipment. In addition, the circuit of the dynamic tuning method is low in complexity degree, and the implementation cost is low, thereby being easy to popularize.

The invention provides a comprehensive frequency modulation control method for a wind power plant. The method comprises: according to the rotating speed-power curve of the fan at different wind speeds, setting object function thereof, obtaining the maximum value of the target function; determining rotating speed limit values of the fan at different wind speeds; forming rotation speed limiting intervals of different wind speeds, merging the rotation speed limiting intervals into comprehensive frequency modulation control, performing reciprocal operation of weighted average on the wind speed, frequency difference and frequency change rate of a fan to obtain frequency modulation action delay of each fan, and staggering frequency modulation action time of each fan in a wind power plant throughmatching of a time sequence of the frequency modulation action delay of the fan. According to the comprehensive frequency modulation control method, the wind speed difference and relative independence of each fan are considered, each fan is matched according to the time sequence, the frequency modulation action time of each fan of the large-scale wind power plant is staggered, the time sequence matching among the fans of the wind power plant is realized, and greater transient disturbance caused by simultaneous action is avoided.

The invention provides a microgrid power quality treatment method and device, and the method comprises the steps: considering the power quality treatment benefit, setting an objective function as theminimum microgrid operation cost, and building an economical active optimization model as an upper optimization model; considering that the objective function is the minimum node voltage deviation andthe minimum node harmonic voltage distortion rate of the microgrid, and taking the power quality management optimization model for managing the node voltage deviation and the harmonic distortion rateas a lower-layer optimization model; and calculating and reasonably distributing the capacity of the grid-connected inverter by utilizing the upper-layer optimization model and the lower-layer optimization model, so that grid connection of the grid-connected inverter according to power requirements is realized, and meanwhile, electric energy pollution of grid-connected nodes can be effectively treated by utilizing the residual capacity of the grid-connected inverter.

The invention discloses a control method of a converter with multiple modules directly connected in parallel. The control method comprises the steps: determining the product of the number of convertermodules connected to an alternating current winding of a transformer in parallel and the current phase number of a single converter module; determining the quotient of 360 degrees and the product asa target angle; and staggering carrier waves loaded on the converter modules to make the phases of the carrier waves sequentially differ by the target angle. According to the control method of the converter with the multiple modules directly connected in parallel, high-frequency harmonics near the switching frequency can be reduced in the converter with the multiple modules directly connected in parallel, and active power output by the system is greatly improved. The invention further provides a control system of the converter with the multiple modules directly connected in parallel and a computer readable storage medium; and corresponding technical effects are achieved.

The invention relates to dual alternating current chopper speed regulation of a wound-rotor asynchronous motor, which belongs to the technical field of electrical engineering. Rotor resistance speed regulation has the disadvantages of large energy loss and difficulty in realization of stepless speed regulation. A speed regulating scheme containing an inverter link has the disadvantages of complex system, low power factor and narrow speed regulating range, and is not suitable for low-power motors. A scheme that a main rotor loop contains a direct current chopper link has the disadvantages of large current capacity and poor reliability of a self turn-off element which is used. Aiming at the problems, the invention provides a new technical scheme, i.e. a dual alternating current chopper is used for chopping slip voltage, so as to change an equivalent value of the slip voltage to realize the stepless speed regulation and achieve the effects of more significant energy saving effect, higher power factor, better starting performance and mechanical properties, wider speed regulating range, small current capacity of the self turn-off element and simple and reliable system. The scheme can be used for large speed ratio stepless speed regulation of the wound-rotor asynchronous motor in various sizes and is especially suitable for the situation that impact load often occurs.

The intelligent miniature circuit breaker comprises a circuit breaker body, an energy storage switch is installed on the upper left portion of the circuit breaker body, one side of the energy storage switch is connected with a motor, a wire inlet hole is formed in the outer surface of the circuit breaker body, and a remote control assembly is arranged on the lower surface of the wire inlet hole. One side of the remote control assembly is provided with a groove, the outer surface of the other side of the groove is provided with an alarm detection assembly, the other side of the alarm detection assembly is provided with an insulation protection assembly, and one side of the outer surface of the insulation protection assembly is provided with an opening electromagnet. According to the intelligent miniature circuit breaker, through the arrangement of the wired communication interface, the control chip, the synchronous signal chip and the voltage acquisition unit, remote control can be effectively realized, current can be switched on and off in time, and electrical and parameters can be remotely acquired, so that the optimal remote control effect is achieved.