81results about How to "Suppress power fluctuations" patented technology

A wind power generator system according to the present invention includes: a windmill rotor including a blade having a variable pitch angle; a generator driven by the windmill rotor; and a control unit controlling the output power of the generator and the pitch angle of the blade in response to the rotational speed (ω) of the windmill rotor or the generator. The control unit performs a first control in which the output power is controlled in accordance with a predetermined power-rotational speed curve until the rotational speed (ω) is increased to reach a predetermined rated rotational speed, and performs a second control in which the output power is controlled to a predetermined rated power when the rotational speed (ω) exceeds the rated rotational speed; the control unit is responsive to the pitch angle for maintaining a state of performing the second control is or for switching to a state of performing the first control, when the rotational speed (ω) is reduced below the rated rotational speed after the control unit is once placed into the state of performing the second control. This provides a wind power generator system which suppresses output power fluctuation and generation efficiency reduction when a transient wind null occurs.

The invention discloses a new-energy-consumption-based source-grid-load coordination control method and system. On the basis of continuous increasing of a new energy scale and occurrence of a novel controllable load, overall cooperative dispatching is carried out on dispersed controllable loads in a region by using a multi-element coordination control technique, thereby realizing characteristic complementation between the several kinds of energy and controllable loads and thus realizing source-grid-load interaction. According to the invention, the new-energy-consumption-based source-grid-load coordination control system is divided into a whole network optimization scheduling layer, a regional monitoring and coordination layer, a local monitoring and control layer, and a primary equipment layer. With utilization of the network communication, data processing and coordinated control technologies, the system provides a technical base for a novel integrated operation mode of regional multi-energy power generation and production, load electricity usage and grid operation by taking improvement of the consumption capability of the new energy of the grid as an objective.

A wind turbine generator system includes: a wind turbine rotor including a blade having a variable pitch angle; a generator driven by the wind turbine rotor; and a control unit controlling the output power of the generator and the pitch angle of the blade in response to the rotational speed of the wind turbine rotor or the generator. The control unit performs a first control in which the output power is controlled in accordance with a predetermined power-rotational speed curve until the rotational speed is increased to reach a predetermined rated rotational speed, and performs a second control in which the output power is controlled to a predetermined rated power when the rotational speed exceeds the rated rotational speed; the control unit is responsive to the pitch angle for maintaining a state of performing the second control is or for switching to a state of performing the first control, when the rotational speed is reduced below the rated rotational speed after the control unit is once placed into the state of performing the second control.

The invention relates to a coordination operation method of a pneumoelectric integration energy distribution network system. An alternating current trend in a power distribution network and gas water conservancy calculating in a gas distribution network are simultaneously considered. A combined cooling heating and power system (CCHP) in a system is taken as a coupling component of the gas distribution network and the power distribution network. Mathematical modeling is performed on a nonlinear multi-energy coupling external characteristic of the CCHP system. Through coordinating and optimizing operation of the CCHP system, a power fluctuation of distributed new energy of the power distribution network is transferred to the gas distribution network and a cold/heat supply system so that a power distribution network connection line exchange power fluctuation is restrained. For a mixing integer non-linear planning problem corresponding to the above model, the invention provides a two-stage optimization algorithm to solve. A simulation example shows that under the condition that a new energy utilization rate of an integration energy system is guaranteed, the method can be used to effectively restrain the power fluctuation on a connection line under different season scenes.

The disclosed windfarm control system comprising a windfarm and a central controller; the windfarm including plural wind power generators whose rotational speeds are variable, plural aerographs disposed in the vicinity of the wind power generators to measure the directions and powers of the wind at the sites of the generators, and plural local controllers disposed in the vicinity of the wind power generators to control the output of the wind power generators by controlling the rotational speeds of the generators; wherein the central controller calculats the control level which maintains the output of the windfarm constant for a predetermined time period and instructs the local controllers to control the rpm's of the wind power generators in accordance with the control level.

The invention relates to the field of distributed power generation and microgrids and discloses a microgrid on-grid to off-grid switching control system. The system comprises an energy-storage bidirectional converter, an on-grid switch and a controller; one side of the on-grid switch is connected with the output end of a main power source; the other side of the on-grid switch is connected with the output end of the energy-storage bidirectional converter; the output end of the energy-storage bidirectional converter is connected with a controller; if the controller receives a connection command, the controller adjusts main grid side voltage and microgrid side voltage of the on-grid switch in the same period; after the on-grid switch is closed, the energy-storage bidirectional converter converts from a voltage source mode to a current source mode and keeps current power unchanged; after on-grid time reaches set delay time, the energy-storage bidirectional converter outputs active power and reactive power. The invention further discloses a control method based on the system. By the use of the system, the problem that switching of the running mode of a microgrid causes disturbance to a load and a grid is solved, and seamless off-grid to on-grid switching is achieved.

The invention provides an auxiliary frequency modulation method for cluster temperature control loads to participate in power network AGC. The dynamic characteristics of temperature control loads anduser comfort are analyzed to evaluate the adjustable capacity range of cluster temperature control loads; according to the different intervals of Area Regulation Requirement (ARR) signals, the coordinated control principle of dynamically distributing the AGC secondary frequency modulation demand to the conventional generating unit and the temperature control load is formulated, the operation timeof auxiliary frequency modulation of the temperature control loads, the operation depth and specific operation mode are determined so as to make full use of the performance advantage of temperature control load without affecting the comfort of users, reduce the frequency modulation pressure of conventional units, speed up the frequency regulation speed, restrain the power fluctuation of tie line of interconnected power network, and effectively improve the frequency modulation effect of power network.

The invention provides a monitoring method of a micro-grid system capable of automatically realizing energy balance. The monitoring method comprises the steps of S1, acquiring operation data of a wind-powered generating device and a photovoltaic generating device through a wind-powered generating device module and a photovoltaic generating device module on real time, and storing the data; S2, predicating output power of the wind-powered generating device and the photovoltaic generating device within the preset time in the future according to the operation data of the wind-powered generating device and the photovoltaic generating device; S3, detecting to obtain SOC of a storage batter module and capacitance voltage values of a super capacitor on real time, and acquiring the load power demand condition in a micro-grid on real time; S4, acquiring large grid parameters and scheduling information on real time, and predicating the power demand of a connecting point between the micro-grid and the large grid in the future; S5, optimally operating the micro-grid by using the power demand of the connecting point between an energy storing station and the large power grid, the current energy SOC of the storage battery and the capacitance voltage of the super capacitor, the current load power demand in the power grid, and the output power of the wind-powered generating device and the photovoltaic generating device in the future as the constraining conditions.

The invention relates to an operation and monitoring method for a micro-grid with an energy storage system capable of stabilizing power fluctuation. The method comprises the following steps: S1, a wind power generation equipment and photovoltaic power generation equipment monitoring module acquires operation data of wind power generation equipment and photovoltaic power generation equipment in real time and stores the data; S2, according to the operation data of the wind power generation equipment and the photovoltaic power generation equipment, output power of the wind power generation equipment and the photovoltaic power generation equipment in future preset time is forecast; S3, an SOC of a storage battery module is detected and acquired in real time, and a power demand condition of loads in the micro-grid is acquired in real time; S4, parameters and scheduling information of a large-scale power grid are acquired in real time and a power demand of a connection point of the micro-grid and the large-scale power grid in future time is forecast; S5, by using a power demand of a connection point of an energy storage power station and the large-scale power grid, a current SOC of energy storage of a storage battery, a current power demand of the loads in the micro-grid and future output power of the wind power generation equipment and the photovoltaic power generation equipment as constraint conditions, optimized operation of the micro-grid is realized.

The invention provides an independent microgrid energy optimization control method based on bi-fuzzy control. The method is characterized by carrying out cost modeling on an energy storage unit and various loads, and for the microgrid peak end valley characteristics, making a day-ahead start and stop plan; then, carrying out optimal power allocation through a first layer of fuzzy control and through mutual cooperation of wind-stored energy and elastic load; and filtering a high-frequency component in fluctuating power through a low-pass filtering algorithm, and carrying out secondary power distribution through a second layer of fuzzy control, thereby ensuring real-time power balance of a microgrid, and reducing capacity of an energy storage device for stabilizing power fluctuation. The method can ensure power balance of the independent microgrid, realizes peak shaving and valley filling of the microgrid, realizes suppression of instantaneous power fluctuation, reflects effectiveness and correctness of energy control and realizes economic operation of the independent microgrid.

The invention discloses a method for measuring the sight line stabilizing accuracy of a photoelectric sight-stabilizing system, and belongs to the technical field of optical measurement. The method is characterized by comprising the following steps that: a plane reflector is fixed on an inner ring frame of the photoelectric sight-stabilizing system to be measured, the photoelectric sight-stabilizing system to be measured is in a vibration state, a measuring laser beam is subjected to strength stabilization, spatial filtering and collimation and then irradiates the plane reflector, a complementary metal oxide semiconductor (CMOS) camera transmits a light spot image sequence of a reflected light beam imaged on a target surface to an image recording and processing system, and the image recording and processing system performs a series of processing on the light spot image sequence to obtain a light spot center-of-mass coordinate sequence, a stabilizing accuracy value sequence and stabilizing accuracy value sequence standard deviation, so that the stabilizing accuracy is measured. By the method, the high-accuracy measurement of the sight line stabilizing accuracy of the photoelectric sight-stabilizing system is realized; and the method can be popularized to the fields of measurement of the stabilizing accuracy of a gun control system and the like, and is wide in application prospect.

The invention proposes a distributed photovoltaic power generation system control strategy based on a virtual synchronous generator, belongs to the technical field of distribution photovoltaic power generation control, and particularly relates to the distributed photovoltaic power generation system control strategy based on the virtual synchronous generator. The invention provides the distributed photovoltaic power generation system control strategy based on the virtual synchronous generator, which can be used for effectively preventing power fluctuation of the system during the dynamic transition process. The distributed photovoltaic power generation system control strategy comprises a photovoltaic array, a power electronic convertor circuit, a power frequency controller, an excitation controller, a virtual synchronous power generator body control link with feed-forward compensation and a sinusoidal pulse width modulation (SPWM) trigger pulse generation device, wherein the structural key lies in that an output end of the photovoltaic array is connected with an input end of the power electronic convertor circuit, and an output end of the power electronic circuit is connected with an AC bus, a signal input end of the power frequency controller, a signal input end of the excitation controller and a signal input end of the virtual synchronous power generator body control link with the feed-forward compensation.

The embodiment of the invention provides an optical storage micro grid system for realizing energy storage capacity dynamic optimization. According to the power output data of photovoltaic power predication and the requirement data of load power predication, a set algorithm is employed by an energy storage capacity dynamic optimization module to calculate the proportional value between emergency power backup capacity and smooth fluctuation capacity, and the proportional value is transmitted to an energy storage battery management system through a DSP control module. The energy storage battery management system adjusts the emergency power reserve capacity and smooth fluctuation capacity in an energy storage battery, and thus the proportion between emergency power backup capacity and the smooth fluctuation capacity is in accordance with the proportional value after the adjustment. According to the embodiment of the invention, the energy storage capacity of the optical storage micro grid system can be dynamically optimized, the energy storage utilization rate of the optical storage micro grid system can be raised, under the premise of ensuring emergency power supply, the power fluctuation of a grid-connected point is inhibited to the maximum, and the utilization of renewable energy, energy saving and loss reduction are facilitated.

The present invention discloses a generated power control system and control method for an intelligent micro-grid with a medium energy storage function. The control system mainly comprises: a wind-solar complementary power generation system, a photothermal generator set with the medium energy storage function, a micro-grid power control system, etc. The control method comprises: by a micro-grid power control center, receiving a power instruction transmitted from a micro-grid dispatching automation system in real time; collecting generated power of the wind-solar complementary power generation system in real time; and calculating a micro-grid optimal power allocation scheme by an energy management system. According to the power allocation scheme, by carrying out coordination control on heat storage of a heat storage system, a heat release rate, and the generated power of the photothermal generator set, stable output of the generated power of the micro-grid is achieved. According to the control method, technical defects of uncontrollability, discontinuity, large fluctuation adn the like of wind energy and solar generated power, which are caused by change of the external environment, can be overcome, the generated power of the micro-grid is stabilized, electric energy of new energy can be consumed to the greatest extent, and the problem of phenomena of ''wind curtailment'' and ''light curtailment'' in the new energy can be effectively solved.

The invention relates to a micro-grid system capable of automatically realizing energy balance. The micro-grid system comprises wind power generation equipment, photovoltaic power generation equipment, an energy storage device, a first AC/DC bidirectional commutation module, a DC bus, a second AC/DC bidirectional commutation module, loads in a micro-grid and a monitoring device, wherein the first AC/DC bidirectional commutation module is used for connecting the micro-grid with a large-scale power grid and isolating the micro-grid from the large-scale power grid; the second AC/DC bidirectional commutation module is used for connecting the wind power generation equipment, the photovoltaic power generation equipment and the DC bus; the energy storage device comprises a storage battery module, a super capacitor and a bidirectional DC/DC converter connected with the DC bus. According to the micro-grid system, generation power of the power generation equipment in the micro-grid and variation of the loads in the micro-grid can be forecast; power of a connection point of the micro-grid and the large-scale power grid can be tracked and forecast; an optimum control strategy can be made and implemented; the micro-grid is guaranteed to rapidly and stably provide active power and reactive power in the grid connection process according to the requirements of the large-scale power grid; the safety and the service life of the energy storage device can be promoted.

The invention relates to a monitoring device for a micro-grid system capable of automatically realizing energy balance. The monitoring device comprises a wind power generation equipment monitoring module, a photovoltaic power generation equipment monitoring module, an energy storage device monitoring module, a large-scale power grid communication module, a grid-connected operation monitoring module, a load monitoring module, a central control module and a bus module, wherein the wind power generation equipment monitoring module is used for monitoring wind power generation equipment in real time and forecasting generation power of the wind power generation equipment; the photovoltaic power generation equipment monitoring module is used for monitoring photovoltaic power generation equipment in real time and forecasting generation power of the photovoltaic power generation equipment; the energy storage device monitoring module can monitor an SOC of a storage battery module, capacitance and voltage values of a super capacitor and a DC/DC bidirectional transducer in real time; the large-scale power grid communication module is used for acquiring an operation condition and related scheduling information of a large-scale power grid from a large-scale power grid regulation and control center in real time; the grid-connected operation monitoring module is used for controlling a micro-grid to be connected with or isolated from the large-scale power grid; the load monitoring module is used for monitoring loads in an energy storage power station in real time; the center control module is used for determining an operation strategy of the micro-grid and sending a command to each module in the monitoring device so as to execute the operation strategy; the bus module is used for communication of each module of the monitoring device.

The invention discloses an electromagnetic heating device and a heating control method thereof. The heating control method of the electromagnetic heating device comprises the following steps of sampling a current of a switch tube in the electromagnetic heating device to generate a voltage sampling signal; acquiring a current heating power of the electromagnetic heating device, and judging a heating state of the electromagnetic heating device according to the current heating power; selecting corresponding amplification rate to amplify the voltage sampling signal according to the heating state of the electromagnetic heating device, and acquiring a current sampling value according to the amplified voltage sampling signal; and adjusting the heating power of the electromagnetic heating device by comparing the current sampling value with a target current value. According to the method, different amplification rates can be selected to sample the current according to the heating state of the electromagnetic heating device, so that the purpose of preventing power fluctuation of the electromagnetic heating device is achieved, the cooking effect is improved, and serious heat generation of the switch tube can be prevented.

The invention discloses an adaptive virtual synchronous machine control method for a hybrid microgrid converter, and the method employs an adaptive virtual moment of inertia J and an adaptive virtualdamping D in a VSG control system, and achieves the inhibition of the power fluctuation of the hybrid microgrid AC/DC converter. Furthermore, in order to obtain a rated virtual parameter value range,a small signal model is established for the self-adaptive VSG control system, and the damping ratio and the rated damping coefficient are obtained by analyzing the characteristic value of the small signal model and referring to the oscillation angular frequency value of the synchronous generator. According to the method, adaptive virtual rotational inertia J and adaptive virtual damping D are adopted in a VSG control system, and in the angular frequency increasing stage, J is increased, and D is properly reduced at the same time; in the angular frequency reduction stage, J is reduced, and meanwhile, D is properly increased through the double-virtual-parameter self-adaptive control scheme. The system response speed can be ensured, and the power is accelerated to enter a stable state. The dual adaptive virtual parameters can effectively suppress power fluctuation.

The invention relates to an AC/DC coordinated control method and system for integrated control of AC tie-line power change. The method comprises: calculating the DC power modulation amount Pmod and the power urgent promotion or fall-back amount Pemg; distributing the DC power modulation amount Pmod and the power urgent promotion or fall-back amount Pemg; and performing integrated control of AC tie-line power change via control of multi-circuit DC power. According to the technical scheme provided in the invention, by modulating the power of a multi-circuit DC transmission system and urgently prompting or reducing the power, power fluctuation and power threshold-crossing of trans-regional AC tie-lines are inhibited.

The invention provides a composite direct current power modulation method for out-of-limit control of alternating current section power, including the following steps of: calculating direct current power modulation quantity Pmod by alternating current tie line power Pac, to achieve control on fluctuation of the alternating current section power; judging whether the alternating current section power is out of limit by the alternating current tie line power Pac, and if yes , executing the step 3; calculating direct current power emergency control quantity Pemg, and thereby completing the out-of-limit control of alternating current section power. According to composite direct current power modulation method for the out-of-limit control of the alternating current section power, through compounding the direct current power emergency control function on the general direct current power modulation function, an additional monitoring device is not required, namely, the power vacancy of the regional power grid is compensated by emergency power control while achieving the cross-distinct power grid alternating current tie line power fluctuation, the steady state stability limit of the alternating current tie line is kept undamaged, and thereby the transient state and dynamic stability characteristics of the large area interconnected power grid with the complex operation mode and under the complex operating condition can be improved at the same time.