Background technology
The electric field of wind power generation inserts network system, when electrical network is carried green electric power supply, possibly cause many harmful effects to electrical network, and these harmful effects are because of in randomness, intermittence and the uncontrollability of wind.These characteristics of wind cause having and other conventional energy resource power plant different features when wind farm grid-connected.Concretely: because wind at random, intermittently and uncontrollability, the wind-powered electricity generation unit in the wind energy turbine set is difficult for regulating and control is exerted oneself, thereby causes that the wind-powered electricity generation unit sends the fluctuation and the change at random of electric energy.These fluctuations further cause harmful effect to voltage, the frequency of electrical network again with change at random.Wind energy turbine set mainly contains voltage fluctuation and the flickering that causes because of wind speed variation, blower fan switching, wind turbulent flow etc. to the influence of line voltage; Thereby also the stability to line voltage exerts an influence; Especially at comparatively weak electrical network; To cause unexpected transient voltage to fall, cause frequently going offline of voltage ripple of power network and wind-powered electricity generation unit, thereby cause bigger voltage fluctuation and electric quantity loss.
Wind energy turbine set is mainly accounted for the ratio decision of overall system capacity by the wind energy turbine set capacity to the influence of mains frequency.Wind energy turbine set is usually located at apart from electric power main system and load center remote districts or offshore islands far away, links to each other with comparatively weak electrical network.When the wind energy turbine set capacity hour, its characteristic is not remarkable to the influence of electric power system, but along with the increase of wind energy turbine set capacity proportion in system, wind energy turbine set is all the more remarkable to the influence of system.The random fluctuation property of its power output also can compare significantly the influence of mains frequency, and then influences the quality of power supply of electrical network and the operate as normal of system's medium frequency sensitive load.
The establishment and the enforcement of the plan of electrical network traditional scheduler are fully based on the reliability of power supply and the predictability of load.After system's wind-powered electricity generation capacity reaches certain scale, wind at random, intermittently and uncontrollability the arrangement and the enforcement of traditional scheduler plan are challenged.
In recent years; The safe operation of the wind-powered electricity generation unit of wind energy turbine set control begins to come into one's own, and exists voltage, frequency fluctuation, three-phase imbalance and instantaneous voltage to fall, even in the electric power system of non-ideal factor such as external short circuit; The running time of the wind turbine generator how to prolong; Reduce unnecessary off-grid number of times, protect unit to avoid machinery and the electrical impact that causes because of frequent braking brake, become the research focus.
Do not have at present to find explanation or report, do not collect both at home and abroad similarly data as yet yet with similar techniques of the present invention.
Summary of the invention
Cause unexpected transient voltage to fall in order to solve when wind farm grid-connected; Cause frequently going offline of voltage ripple of power network and wind-powered electricity generation unit; Thereby cause bigger voltage fluctuation and electric quantity loss; And problems such as the arrangement of the back power scheduling plan of being incorporated into the power networks and enforcement, the object of the present invention is to provide a kind of wind energy turbine set energy storage regulating system.Utilize the present invention, can effectively improve by wind at random, intermittently and the various problems that are incorporated into the power networks of wind energy turbine set that cause of uncontrollability, the safe operation of protection wind energy turbine set wind-powered electricity generation unit improves the utilance of wind energy turbine set, improves when wind farm grid-connected many harmful effects to electrical network.
In order to reach the foregoing invention purpose, the technical scheme that the present invention is adopted for its technical problem of solution provides a kind of wind energy turbine set energy storage regulating system, and this device comprises:
In wind energy turbine set and be incorporated into the power networks and be provided with a wind-powered electricity generation unit between the transformer, be used to detect voltage, the current signal of output voltage, current signal and the electrical network of wind-driven generator; The signal controlling end of wind-powered electricity generation unit is connected with a central energy storage control system; Central authorities' energy storage control system is connected with the two-way inverter that is incorporated into the power networks with a lithium electricity energy-storage system through the CAN bus; Lithium electricity energy-storage system is connected in parallel on wind-powered electricity generation unit output and the junction of the transformer that is incorporated into the power networks through the two-way inverter that is incorporated into the power networks; The two-way inverter that is incorporated into the power networks is exported into horizontal lock, frequency locking and amplitude modulation to the power of wind-powered electricity generation unit; Central authorities' energy storage control system intercoms through the battery management system of CAN communication mode with lithium electricity energy-storage system mutually; Reception detects voltage, the current signal of voltage, current signal and the electrical network of gained from the wind-powered electricity generation unit; And, the discharging and recharging of lithium battery group of two-way inverter and the lithium electricity energy-storage system that is incorporated into the power networks controlled through the computing and the decision-making of control strategy.
Above-mentioned wind-powered electricity generation unit can be a plurality of, and their power take-off is parallelly connected with the output of the two-way inverter that is incorporated into the power networks; Their signal controlling end is parallelly connected with the signal input part of central energy storage control system.
Wind energy turbine set energy storage regulating system of the present invention; Owing to take technique scheme; A kind of wind energy turbine set energy-storage system based on the lithium battery group is provided; Designed special-purpose batteries management system BMS and the central energy storage control system ESS of wind energy turbine set lithium electricity energy-storage system that constitutes by battery submodule control unit LECU, battery module managing unit B MU, provided wind energy turbine set energy storage control strategy based on the lithium battery group.Accumulation power supply is connected in through two-way combining inverter and is incorporated into the power networks between transformer and the wind energy turbine set.The energy storage controller is according to voltage, current detection signal, the controller signals of wind energy turbine set wind-powered electricity generation unit, the batteries management system signal of electrical network; Carry out energy storage control strategy program; To the control of charging, discharge of lithium electricity energy-storage module, realize when wind farm grid-connected many dysgenic improvement to electrical network.Therefore; The invention solves and cause unexpected transient voltage to fall when wind farm grid-connected; Cause frequently going offline of voltage ripple of power network and wind-powered electricity generation unit, thereby cause bigger voltage fluctuation and electric quantity loss, and problems such as the arrangement of the back power scheduling plan of being incorporated into the power networks and enforcement; Obtain the performance improved when wind farm grid-connected, the steadily power output, machinery, the electric equipment life-span of improving system of wind energy turbine set, guaranteed the stable beneficial effect that waits of mains frequency.
Embodiment
Below in conjunction with description of drawings the preferred embodiments of the present invention.
Fig. 1 is the theory diagram of wind energy turbine set energy storage regulating system of the present invention, and shown in the embodiment of Fig. 1, this device comprises:
In wind energy turbine set and be incorporated into the power networks and be provided with a wind-powered electricity generation unit between the transformer, be used to detect voltage, the current signal of output voltage, current signal and the electrical network of wind-driven generator; The signal controlling end of wind-powered electricity generation unit is connected with a central energy storage control system; Central authorities' energy storage control system is connected with the two-way inverter that is incorporated into the power networks with a lithium electricity energy-storage system through the CAN bus; Lithium electricity energy-storage system is connected in parallel on wind-powered electricity generation unit output and the junction of the transformer that is incorporated into the power networks through the two-way inverter that is incorporated into the power networks; The two-way inverter that is incorporated into the power networks is exported into horizontal lock, frequency locking and amplitude modulation to the power of wind-powered electricity generation unit; Above-mentioned central energy storage control system intercoms through the battery management system of CAN communication mode with lithium electricity energy-storage system mutually; Reception detects voltage, the current signal of voltage, current signal and the electrical network of gained from the wind-powered electricity generation unit; And, the discharging and recharging of lithium battery group of two-way inverter and the lithium electricity energy-storage system that is incorporated into the power networks controlled through the computing and the decision-making of control strategy.Thereby realize the co-ordination of whole wind electric field, and then realize systemic-function, and signal values such as coupled each parts real-time voltage that connects, electric current, power are shown through liquid crystal color screen configuration.Simultaneously, realize the telecommunication monitoring, realize unattended function through communication mode and host computer.In the lithium electricity energy-storage system, battery management system is used for the operating mode of battery pack is monitored in real time, and its function declaration will be explained in Fig. 3.
Wind energy turbine set energy storage regulating system embodiment scheme as shown in Figure 1 is mainly by many typhoons group of motors, many energy-storage battery groups, many two-way combining inverters with organize central control system more and constitute.Wherein, The corresponding typhoon group of motors of energy-storage battery group; Be connected in interchange place of wind-powered electricity generation unit through combining inverter, the power of this wind-powered electricity generation unit output is absorbed or compensate, and then reach stable output, protection wind-powered electricity generation unit, the improvement dysgenic purpose that is incorporated into the power networks.
The above-mentioned two-way inverter that is incorporated into the power networks has the function of lock phase, frequency locking, amplitude modulation; Be used to ensure that the voltage of lithium battery group output has identical phase place, frequency and amplitude with the line voltage at the place of being incorporated into the power networks; The circulation that reduces to cause because of out of phase etc. is to the impact and the harmful effect thereof of equipment and electrical network; Simultaneously, realize the interaction of wind-powered electricity generation unit and energy storage lithium battery group through the mode of rectification or inversion.
Fig. 2 is the theory diagram of another embodiment of wind energy turbine set energy storage regulating system of the present invention; Shown in the embodiment of Fig. 2, above-mentioned wind-powered electricity generation unit can be a plurality of, and their power take-off is parallelly connected with the output of the two-way inverter that is incorporated into the power networks; Their signal controlling end is parallelly connected with the signal input part of central energy storage control system.Embodiment compares and can know among this embodiment and Fig. 1; Its difference is that the position of being incorporated into the power networks of energy storage regulating system changes to some extent; The number of energy storage regulating system also becomes separate unit by many, changes into centralizedly by distributed, and the battery power of lithium electricity energy-storage system also rises to some extent and becomes big.Among this embodiment, the energy storage regulating system absorbs the power that is incorporated into the power networks of whole wind electric field simultaneously or compensates, to improve whole harmful effect to electrical network when wind farm grid-connected.This embodiment adopted with Fig. 1 embodiment in similar control strategy.
Among Fig. 1, Fig. 2 embodiment; Central authorities' energy storage control system also carries out exchanges data through CAN bus network and upper industrial computer, and the CAN bus is a kind of standard industry bus, and its physical structure and serial communication structure are basic identical; Adopt two read-write connections to running status and data such as the electric current of upper industrial computer transmission system operation, voltage, power, faults; On the host computer interface, show, make things convenient for system monitoring and debugging, and receive the startup that host computer transmits; Stop, and the command informations such as set point of various running statuses.Upper industrial computer adopts data collecting card to read desired data from the CAN bus, stores after further handling or shows, convenient system's service data is analyzed.Above-mentioned CAN information identifier is 11.
Fig. 3 is the electrical schematic diagram of energy-storage battery group power-supply management system; This system has functions such as System self-test, charge and discharge protecting, overtemperature protection, charged state prediction, battery pack balancing and high voltage protective; This system is made up of a plurality of battery submodule control unit LECU and a battery module managing unit B MU.Wherein, BMU is the core devices of BMS system, communicates through Local CAN network and LECU, collects the charged state data of monomer battery voltage, temperature and the module of lithium battery group; After handling, communicate through CANB and central energy storage control system ESS; State according to battery pack sends parameters such as data sync, dormancy, intermodule equilibrium and cycle life through Local CAN network to LECU simultaneously.The power supply of whole electric-control system comes from the DC/DC DC power supply of outside 12V.
Among Fig. 3, BMU removes communication function, also has pre-charging functions, with before combining inverter is connected, the high-voltage capacitance of combining inverter is carried out precharge, when guaranteeing that high voltage connector is connected, to lithium battery systems generation impact in battery pack.BMU gathers battery set charge/discharge electric current and total voltage through current sensor, total voltage transducer, and to the judgement of lithium battery group monomer voltage, adopts the method for bypass discharge, and control LECU carries out in the balanced or module of intermodule balanced.Simultaneously, BMU has the clock that do not cut off the power supply, and is used to the lasting record of the time that guarantees, and the important information of the system of being directed against, and for example fault type and time of origin, charge/discharge capacity etc. can regularly carry out store and clear at EEPROM.
Among Fig. 3, LECU is a BMS system bottom module control unit, directly cell is communicated control, between battery and BMU, plays a part to form a connecting link.Its control power supply is provided through the isolated variable mode by BMU.LECU communicates through CAN bus and BMU, through communicating by letter with BMU, storage battery is carried out the equilibrium that bypass is discharged, and can realize equilibrium and intermodule equalization function in the module, and its CAN information identifier is 11.Each LECU can realize the measurement of 8 monomer voltages, and has 8 temperature sensor signals, realizes the temperature acquisition to 8 cells.
Fig. 4 is a wind energy turbine set energy-storage system control signal theory diagram, has provided the signal communication sketch map of whole wind electric field energy-storage system.Can know by figure; The energy storage control system ESS of central authorities is the core of whole energy-storage system, is getting in touch systems such as wind energy turbine set (Wind Farm), electrical network (Grid), the two-way inverter (Inverter) that is incorporated into the power networks, BMU, cooling system (Cooling Model) and host computer.ESS intercoms through the battery management system BMS and the master system of CAN communication mode with lithium electricity energy-storage system mutually, and accepts to detect from the wind-powered electricity generation unit voltage, the current signal of voltage, current signal and the electrical network of gained.These communications, detection signal carry out the computing and the decision-making of control strategy; Inverter and discharging and recharging of lithium battery group are controlled; Realize the co-ordination of whole wind electric field; And then the realization systemic-function, and signal values such as coupled each parts real-time voltage that connects, electric current, power are shown through liquid crystal color screen configuration.
In sum, the present invention has been for the wind energy turbine set energy storage has designed special-purpose a kind of wind energy turbine set energy-storage system based on energy-storage battery, helps improving the performance performance when wind farm grid-connected, guarantees the smooth access of wind energy turbine set electricity generation grid-connecting.More help reducing because of wind-force intermittently causes unnecessary off-grid, the number of times that is incorporated into the power networks between ground wind energy turbine set and the electrical network, prolong the running time of wind turbine generator.
This energy-storage system helps the safe operation of the wind-powered electricity generation unit of wind energy turbine set; The steadily power of wind energy turbine set output; Exist voltage, frequency fluctuation, three-phase imbalance and instantaneous voltage to fall; Even in the electric power system of non-ideal factor such as external short circuit, improving machinery, the electric equipment life-span of system, the protection unit is avoided the machinery and the electrical impact that cause because of frequent braking brake.
This energy-storage system helps ripple is put down in the Power Output for Wind Power Field that turbulent flow the caused fluctuation of wind, and increase inserts the electrical network even running behind the electrical network.Wind energy turbine set mainly contains voltage fluctuation and the flickering that causes because of wind speed variation, blower fan switching, wind turbulent flow etc. to the influence of line voltage; Thereby also the stability to line voltage exerts an influence; Especially at comparatively weak electrical network; To cause unexpected transient voltage to fall, cause frequently going offline of voltage ripple of power network and wind-powered electricity generation unit, thereby cause bigger voltage fluctuation and electric quantity loss.Use system of the present invention, improved the stability of wind farm grid-connected power output, and then reduced the harmful effect of wind energy turbine set electrical network.
This energy-storage system helps improving the stability that wind energy turbine set transmits electric power to the light current net.Wind energy turbine set generally is distributed in apart from electric power main system and load center remote districts or offshore islands far away; Link to each other with comparatively weak electrical network; When the wind energy turbine set capacity hour; These characteristics are not remarkable to the influence of electric power system, but along with the increase of wind energy turbine set capacity proportion in system, wind energy turbine set will more and more significant to the influence of system.Use system of the present invention, improved the impact of wind energy turbine set to the light current net, this stable operation for the light current net is significant.
This energy-storage system helps guaranteeing the frequency stability of electrical network.Wind energy turbine set is mainly accounted for the ratio decision of overall system capacity by the wind energy turbine set capacity to the influence of mains frequency.When the wind energy turbine set capacity hour, its characteristic is not remarkable to the influence of electric power system, but along with the increase of wind energy turbine set capacity proportion in system, wind energy turbine set is all the more remarkable to the influence of system.The random fluctuation property of its power output also can compare significantly the influence of mains frequency, and then influences the quality of power supply of electrical network and the operate as normal of system's medium frequency sensitive load.When electrical network generating occurred and causes frequency to reduce with the load unbalanced supply-demand, the output that the wind energy turbine set energy-storage system can increase power in short-term to be satisfying the demand that in short-term increase of electrical network to active power, thereby guaranteed the stable of mains frequency.
This system helps increasing the reliability of holding of wind energy turbine set, and what change wind energy turbine set can not scheduling property.Because the uncontrollability of wind energy, thereby can not come wind power generation is dispatched according to the size of load, no small pressure brought to dispatching of power netwoks.Use system of the present invention, ensured the schedulability of wind energy turbine set in certain power bracket, in electrical network, hold reliability, increased the safe operation of electrical network thereby improved wind energy turbine set.