DE19716645A1 - Power transmission method used between fluctuating current generator and supply network - Google Patents

Abstract

The power transmission method is used for transmitting the power provided by a fluctuating current generator (5) to the current supply network (15) and has an electrochemical energy store (27) for correcting the difference between the output power (P1) of the generator and the power (P5) supplied to the supply network. The electrochemical energy store is charged by the excess power from the energy generator when the power provided by the latter is greater than that supplied to the supply network and provides supplementary power when the power provided by the generator is less than that supplied to the supply network.

Description

The invention relates to a method and a device for transmitting electrical Power from a fluctuating energy, especially wind energy, processing Electricity generator for the power network of an energy supply system.

Fluctuating energy processing power generators are, for example, wind energy Investments. The vast majority of these systems become more parallel to the grid or less strong interconnected network and feeds the generated electrical power, which fluctuates in time due to the fluctuating nature of the wind, directly into the power grid. The fluctuations in performance depend on the wind conditions nissen in the hour, minute or second range and are only limited beforehand determinable. Even with precise weather forecasts, forecasts can only be made in the Carry out hourly range.

Since a large part of the consumers fed by conventional electricity networks come from technical Based on a relatively constant mains current in terms of voltage and frequency is dependent, the energy supply companies as network operators must do this ensure that these requirements are met, d. H. that the total power generated in narrow limits of the total power consumed is tracked. Otherwise stay Network voltage and frequency not constant. The greater the proportion of electricity  the producer with fluctuating powers unknown over time, the more the demands on the control behavior of the rest of the power plant fleet are increasing.

Should the proportion of the mains electricity generated from wind or the like be increased in the interest of The use of wind energy will continue to increase, so the planning of the Additional services to be provided at times are correspondingly more difficult because the Fluctuations in the power from wind are in the minutes and seconds range and stochastic in nature and therefore cannot be planned. On the side could help here the wind turbines operated in parallel to this energy storage by this to Equalization of the generated power then feed into the network if the wind power currently generated is too low. Such energy storage devices are, however previously only used for reasons of cost where they are absolutely indispensable. This happens z. B. in so-called island networks, where even a larger proportion of the basic service is generated by wind energy and z. B. a diesel generator and a battery storage Lulls can provide additional electrical power. Again, the sum the total power delivered to the network adapted to current needs, d. H. tracked the respective power consumption.

The question was raised in a system study carried out in 1977 using a simulation examines whether it could be made possible for the operators of wind turbines, an energy supply company over pre-selected time intervals To give performance guarantees, as z. B. when operating a running water works can already be calculated from the current water levels, and a needs-based one Performance regulation on the side of the energy supply companies significantly united fold (Molly, Jens-Peter, Windenergie, Verlag C.F. Müller, 2nd edition 1990, Pp. 220 to 228). The system study is largely based on which of a period of e.g. B. One year of incurred benefits with a Wind turbine can be achieved, which constantly guaranteed minimum performance can be derived from this for future time intervals and how large the probability is speed is that such minimum benefits due to the actual wind conditions can not be met. In addition, a. meteorological Forecast data as well as data that have already been given in previous intervals Describe services to determine forecast values for at future intervals  deliverable and guaranteed services used, each taking into account storage, which is used to maintain guaranteed performance values can be removed or supplied, the presence in the special case a pump storage is required. Whether and if so how from the system study the knowledge gained can be put into practice is not specified.

In contrast, the invention is based on the object, the methods described and to design devices in such a way that even when using a fluctuating Energy processing power generator, especially a wind turbine possible is, on the one hand, an energy supply company for successive time intervals To guarantee valid services that exactly predict each one of these time intervals have the right course, and on the other hand the energy supply companies in good time to be able to put the guaranteed benefits into their own plans to involve.

The features of claims 1 and 7 serve to achieve this object.

Further advantageous features of the invention result from the subclaims.

The invention has the advantage that the guaranteed or guaranteed Performances independent of the nominal power of the respective power generator and the Weather conditions are. The invention is based on the knowledge that the guaranteeable To measure performance and the time interval for which this performance is guaranteed are that the given performance guarantee even in the event of an unforeseen change in the Forecasts that weather conditions or the like can be met. Can be prognosti adorn that under the given circumstances for a selected time interval none defined power can be guaranteed, the energy supply company accordingly informed that no service was delivered at all in this time interval becomes. This is based on the further realization that one also has a value of zero corresponding performance guarantee far better in the planning concept of an energy ver care company, as if one did not define one for any time interval te service is offered, and that it is ultimately the utilities it does not matter how large the guaranteed services and the preselected time intervals  are, if only the power that is actually fed in is a previously known one Has course. The invention thereby creates the conditions for the fact that electricity producers who process fluctuating energy, especially wind energy, in larger numbers Number can be used than before, without the above mentioned Difficulties on the part of the energy supply companies are increasing accordingly men.

The following is a summary of preferred embodiments hang with the accompanying drawings, in which:

FIG. 1 is a block diagram of an arrangement coupled to a power grid and consisting of a speed-rigid wind power plant operated in parallel with the grid and a device according to the invention;

FIG. 2 is a block diagram of an arrangement coupled to a power grid, consisting of a variable-speed wind power plant operated in parallel with the grid and a device according to the invention;

Fig. 3 shows the sequence of time intervals in connection with a prognosis for a future deliverable power of the wind turbine; and

Fig. 4 shows in an overview certain, the method according to the invention characterizing power or energy profiles at different points of the device according to the invention shows.

With reference to FIG. 1, a rigid wind turbine, which is designated as a whole by the reference numeral 1 , contains a rotor 3 and a generator 5 connected to it in the form of a generator, to which an outgoing transmission line 7 is connected, in which The power P ₁ generated by the power generator 5 is transmitted via a coupling point 9 , to which a device 11 according to the invention is connected in parallel, to a transformer 13 , which up-transforms the generated alternating voltage for feeding into a power grid 15 . The network frequency f is directly impressed on line 7 by the network.

The inventive device 11 includes a generator 5 connected to the output side of the current transducer 17, of the apparatus via a line 19 with a forecast 21 is connected and that a signal feeds, which is characteristic of the currently output by the current generator 5 power P. ₁ The forecasting device 21 can preferably be designed as a programmable or programmed electronic chip module and, because of its programming, is suitable for making a forecast from the tapped power signal as to which power P ₂ the power generator 5 of the wind turbine 1 is able to deliver in a future time interval or will probably give up. This power P ₂ is communicated through a line 23 to an input of a setpoint value determiner 25 , which outputs a setpoint value at its output corresponding to a power P ₃ to be supplied to the power grid and, in turn, is preferably also designed as a programmable or programmed chip module. Furthermore, the device 11 has an electrochemical memory 27 for storing electrical energy, to which a unit 29 which detects the state of charge of the memory 27 is connected, the output of which is connected via a line 31 to a further input of the setpoint generator 25 . The output of the setpoint mean 25 is connected via a line 33 to a controller 35 , which in turn is connected via a control line 37 to the control input of an actuator in the form of a controllable charging and discharging device 39 connected between the coupling point 9 and the memory 27 , by means of which a power P ₄ which can be preselected in terms of amount and direction can be fed or taken from the memory 27 . As a result, depending on the control signal carried in the control line 37 , power can be fed from the power generator 5 into the memory 27 , power can be fed from the power grid 15 into the memory 27 or power can be delivered from the memory 27 into the power grid 15 will. The loading and unloading device 39 is, for. B. formed as a bidirectional switching element and preferably realized by power thyristors, triacs or the like. In a rigid wind turbine 1 , as shown in Fig. 1, the charging and discharging device 39 is particularly advantageously designed as a bidirectional inverter which is controlled via an antiparallel thyristor bridge which enables reversal of the current direction, the amount of the flowing current being above the control angle of the inverter is determined. The sum of the power P ₁ currently generated by the generator 5 and the instantaneous storage charging or discharging power P ₄ , which can be positive or negative, thus opens into the coupling point 9 . The total power is delivered as total power P ₅ to the transformer 13 for transmission into the power grid 15 . The memory 27 may e.g. B. consist of an electrochemical lead-acid battery, which is composed of individual cells á two volts, which are interconnected by series and / or parallel connection to form a battery system.

Between the coupling point 9 and the transformer 13 , a measuring device 41 in the form of a transducer or the like is provided, which detects the instantaneous actual value of the power P ₅ delivered to the power grid 15 and feeds it via a line 43 to a further input of the controller 35 . In this way, a closed control loop is obtained, the transmission line 7 , the measuring device 41 , the setpoint 25 , the controller 35 , the summing point formed at the input of the two lines 33 , 43 and contains the loading and unloading device 39 .

Finally, a branching point 45 connected into line 33 is provided, which leads via line 46 to a registration device 47 , via which a power supply company 49 operating the power network 15 is informed of the transmission powers P ₃ in time intervals that occur in the near future, e.g. B. in an hour, begin to be supplied to the power grid 15 and which correspond exactly to the setpoint powers P ₃ delivered by the setpoint determiner 25 and supplied to the controller 35 . Since the control loop described has no significant inertia, the power P ₅ supplied to the power grid 15 can be brought very precisely into line with the setpoint powers or the powers P ₃ registered via the registration device 47 , that is to say the power P ₅ is independent of that power P ₁ actually output by power generator 5 has an almost ideally smoothed profile.

As a particularly preferred variant of the embodiment shown, the controller 35 is optionally connected via a line 51 to an actuator 53 for the blade adjustment of the rotor 3 , whereby the device 11 according to the invention is set up with an additional control variable for the wind power captured by the rotor 3 .

The arrangement shown in FIG. 2 differs from that according to FIG. 1 only in that the integration of the device 11 according to the invention in a variable-speed wind turbine 1 is shown. The same parts are therefore provided with the same reference numerals in FIGS. 1 and 2. The coupling point 9 for coupling the memory 27 is here in the DC link of an intermediate circuit converter, which serves to decouple the rotor speed from the mains frequency, is connected to the transmission line 7 and a rectifier 57 connected to the generator 5 and an inverter connected to the transformer 13 59 has. Therefore, a charging and discharging device 61 for the memory 27 here expediently consists of a controllable direct current converter in the form of a unit consisting of a step-up and step-down converter. If power is to be taken from the memory 27 for control purposes, the step-down converter part is controlled by the controller 35 , for example, while the step-up converter part of the DC converter is controlled when the power is fed into the memory 27 .

FIG. 3 schematically shows the chronological sequence of the work of the forecasting device 21 , which cyclically processes data at times T _i-1 , T _i , T _{i + 1} , T _{i + 2} etc., which are generated by the power generator 5 for the duration of a previous one , generated at ΔT ₀ time interval and delivered by the transmitter 17 . The time interval ΔT _{0 can} extend directly to the respective time T _i-1 , T ₁ etc., but can also be in the past and end before the time in question. The forecasting device 21 then provides an estimated power P ₂ at each time T _i , which is to be delivered in a time interval ΔT ₂ that begins only in the future, the start of which is spaced, for example, by a time interval ΔT ₁ from the time T _i , etc. in question is. Here, all times T _i-1 , T _i T _{i + 1} , T _{i + 2} , etc. suitably follow one another at constant intervals, and the time intervals ΔT ₂ are preferably the same in each case, although they can be chosen individually in each case . The same applies to the time intervals ΔT ₀ and ΔT ₁ . Since the data supplied by the transducer 17 are stochastic in nature, they are preferably time-resolved, ie they represent the power P ₁ in minute or second intervals.

The manner in which the data supplied by the transmitter 17 is processed in the forecasting device 21 is variable within wide limits. A simple processing is such. B. in that a mean value for the output power P _{1 is} determined for the past time interval ΔT ₀ and this average value is output as power P ₂ for the future interval ΔT ₂ . Such a forecast or estimate is based on the assumption that the actual output in the interval ΔT ₀ will repeat in the preselected th later interval T ₂ , especially if the considered and preselected intervals ΔT _{0 are} comparatively short and only a few hours and if the intervals ΔT _{2 are} only spaced from the associated times T _i by short intervals of likewise a few hours. It would also be possible, alternatively or additionally, to connect the forecasting device 21 to a wind measuring device via a line 63 and / or to supply it with the forecast data supplied by a weather service via a line 64 . For this purpose, the forecasting device 21 is preferably designed in the manner of a microprocessor, which processes all the supplied data according to a preselected forecasting program and uses this to calculate the powers P ₂ . In particular, a conventional industrial PC can be used for this purpose, wherein both devices 21 and 25 can also be combined in a single industrial PC.

The target value determiner 25 processes the performance data P ₂ output by the forecasting device 21 and the data output by the unit 29 and corresponds to the current filling level of the memory 27 and calculates from this the powers P ₃ which depend on the data mentioned and taking into account the capacity of the memory 27 can be delivered in any case in the next preselected time interval ΔT ₂ if the powers P ₁ and P ₄ are added in this time interval. This power P ₃ is reported on the one hand via the registration device 47 to the energy supply company 49 as the "guaranteeable" power for the next time interval ΔT ₂ and on the other hand fed to the controller 35 as a setpoint.

The process according to the invention therefore proceeds essentially as follows:
The prediction device 21 uses the specified data to determine an estimated or predicted value for a power that can presumably be output by the electricity generator 5 in a later time interval. However, since this performance does not yet represent a guaranteed soldering for any time interval, the content of the memory 27 is also taken into account in the setpoint value determiner 25 and checked, which performance can still be guaranteed even if the prognosis proves to be essentially incorrect. After determining this the setpoint for the controller 35 power P ₃ , this is registered with the energy supply company with a certain lead time ΔT ₁ , and also this power P _{3 is given} to the controller 35 as a setpoint at the beginning of the next time interval ΔT ₂ . The latter then calculates the differences between the power measured at the output of the coupling point 9 and currently supplied to the power grid 15 and the predetermined target value and then adjusts the charging and discharging device 39 or 61 such that the sum of the power currently output by the power generator 5 P ₁ and the power P ₄ currently withdrawn or supplied to the memory 27 always correspond exactly to the registered power, which can be practically achieved in the millisecond range with the presupposed control device. The output and the guaranteed power therefore have a defined, deterministic course independent of the power P ₁ actually output by the power generator 5 .

The described method can be carried out regardless of the chronological course of the guaranteed performance. Normally it can be assumed that the total power P ₅ actually delivered is constant at least within each preselected time interval. But it would also be conceivable to change the overall performance over time, e.g. B. slowly increasing or decreasing and thereby preferably give a linear course, for example to avoid abrupt jumps in performance between successive time intervals. In these cases, it is only necessary to design or program the target value determiner in such a way that the values P _{3 given by it have} a corresponding time profile. This results in the essential advantage for the invention that the energy supply company for each preselected time interval not only any more or less certain power, but a power can be supplied with a predetermined and logged th time history.

Another advantage of the method according to the invention is that it also leads to a meaningful reading if, at any point in time T _i, the current memory content is too low to indicate a total output with a predefined progression for a subsequent time interval ΔT ₂ can. In this case, the energy supply company 49 is informed via the registration device 47 that the value of the power guaranteed for the next time interval is zero. The relevant time interval is then used to refill the memory 27 , for which purpose a power that is later supplied by the power generator 5 can be used. However, since it is not clear how quickly this can lead to sufficient charging of the memory 27 , the required power is expediently registered for the next preselected time interval via the registration device 47 and then removed from the power supply 15 with a defined course by corresponding control of the control device, so that the method according to the invention can be resumed in the subsequent time interval.

The capacity of the memory 27 is in itself arbitrary, because the length of the time intervals in which guaranteed services and power courses must be delivered to the power grid 15 can be adapted to this capacity. Apart from this, the capacity of the memory 27 naturally also depends on the nominal power of the respective power generator 15 . Overall, however, the capacity should be chosen at least so large that each time interval ΔT _{2 can be} at least two to three hours. It is also advantageous if the guaranteed powers P ₃ and the lengths of the time intervals are selected so that an average charge of the memory 27 is achieved before and after the start of each preselected time interval. As a result, the store 27 can be operated gently and approximately uniformly in the loading and unloading direction. According to a particularly preferred embodiment of the invention, the arrangement is also such that the memory 27 is never completely emptied, but always z. B. has at least a fill level of 20%, in which case the registration device 47 already reports a power corresponding to the value zero if this minimum fill level would have to be fallen below in a subsequent time interval. The minimum degree of filling could be kept in front of the energy supply company 49 in such a way that it can always refer to it if necessary. This can e.g. B. by means of a bidirectionally operable registration device 47 and line 46 , via which the setpoint determiner 25 is programmed on request so that it delivers the power corresponding to the degree of filling of 20% in a specified time interval, in deviation from the other regulation.

In FIG. 4, the power or energy waveforms at various points of the device 11 according to the invention are shown in a comparative table, wherein in X-direction, a uniform sized in hours time scale is specified, an arbitrary part of the day is between 3: 00 and 12 : 00 designated. The sizes P ₁ to P _{5 have} the meaning given above, while P _N the nominal power of the wind energy installation, E the instantaneous state of charge of the store 27 and E _max the maximum storage capacity of the store 27 . The ordinate values are also normalized to the associated maximum values of the nominal power or the maximum storage capacity.

In the following, the creation of a constant first actual value P ₅ for the transmission to the energy supply company 49 is first described during a first time interval from 6:00 a.m. to 9:00 a.m.

From the restless, non-constant course of P ₁ essentially above the 50% mark between 3:00 a.m. and 6:00 a.m., the forecasting device 21 calculates a constant, mean value for P ₂ , which is approximately 59% (second box from above in Fig. 4) and is essentially supported by the assumption that the relatively high course of P ₁ continues as it was in the interval from 3:00 a.m. to 6:00 a.m. It is advisable to assume an average value from this interval for the forecast performance in the new interval.

The setpoint value determiner 25 assumes this result, but calculates that the state of charge of the memory 27 shortly before 6:00 a.m. is somewhat - approximately 10% - above an optimally assumed state of charge, which is shown in the third box from above in FIG. 4 is represented by a dashed line 65 and z. B. corresponds to a value of 60% of the capacity. The target value determiner 25 assumes that the memory 27 is still discharged up to the line 65 in the next three hours of a subsequent logon interval and that the target value P ₃ can therefore be selected to a certain extent higher than P ₂ . In the exemplary embodiment, the value P _{3 is} z. B. at about 66%. As a result, this value is guaranteed to the energy supply company 49 with a constant course of the transmission power at this value.

In the interval between 6:00 a.m. and 9:00 a.m., however, the actual course of the power P ₁ is on average not as high as was forecast. In order to achieve the control goal nevertheless, the controller 35 continuously withdraws power P ₄ from the memory 27 during this interval in accordance with a discharge power (fourth box from above), which fluctuates essentially in the same manner as the fluctuations in the power P ₁ actually achieved . The state of charge approaches the selected deep discharge limit of approx. 20%, which is shown as broken line 67 and should only be undercut in exceptional cases. At the end of the interval, ie at 9:00 a.m., the degree of filling is still around 30%. The memory 27 should therefore be charged more heavily in the following interval.

A comparison of the curves of P ₅ (bottom box in Fig. 4) and P ₃ shows that the control target - actual value equal to setpoint - was exactly achieved in the interval from 6:00 a.m. to 9:00 a.m.

Next follows the description of the transmission of a time-constant total energy P ₅ during a subsequent time interval from 9:00 a.m. to 12:00 p.m. It is assumed for the sake of simplicity, as in the example above, deviating from FIG. 3, that the time intervals in which guaranteed energy is supplied immediately follow those periods that were used to predict the values P ₂ .

From the course of P ₁ substantially below the 50% mark between 6:00 a.m. and 9:00 a.m., the forecasting device 21 calculates an average constant value for P ₂ of approximately 35%, again on the assumption that the relatively low one P ₁ continues as it was in the interval from 6:00 a.m. to 9:00 a.m. In the special case, however, the forecasting device 21 is based on additional data, e.g. B. the data supplied via lines 63 , 64 or additional data taken from long-term statistics, assume that in the time interval from 9:00 a.m. to 12:00 p.m. a greater output of e.g. B. 55% can be realized.

The target value determiner 25 assumes this result, but calculates that the state of charge of the memory 27 shortly before 9:00 a.m., the start of the second registration interval, is far below the optimal state of charge of 60% and the memory 27 is therefore in the should be recharged to its optimal charge level of 60% in the next three hours. In order to achieve this goal, he sets the target value P ₃ to a value that is considerably lower than P ₂ and is approximately 35%. Furthermore, it in turn guarantees the energy supply company 49 that the transmission power will remain constant at this value.

However, in the interval between 9:00 a.m. and 12:00 p.m., the actual course of the power P ₁ is higher on average than was forecast. In order to achieve the control goal, the controller 35 therefore continuously charges the memory 27 during this interval with a certain, fluctuating power which corresponds to the difference between the values P ₁ and P ₃ . As a result, the memory 27 exceeds its optimal filling state, and at the end of the interval, ie at 12:00 p.m., its state of charge is around 80%, which necessitates a greater discharge in the following interval.

A renewed comparison of the curves P ₅ and P ₃ shows that the control target was optimally achieved even in the interval between 9:00 a.m. and 12:00 p.m.

The transition of the transmission power P ₅ from any interval to a subsequent interval is often associated with a jump in performance, as the line P ₅ in the bottom box of FIG. 4 reveals at approximately 9:00 a.m. Since such jumps in power should be avoided when feeding power into the power grid 15 , the invention provides for such a case at the beginning of the relevant interval a course for the total power that follows a line 69 indicated in the bottom box of FIG. 4 and one gradual and steady transition between the constant powers in the two successive time intervals. This steady transition can also be realized with the aid of the control device described, since abrupt transitions of this type are often already reflected in the power output by the power generator 5 and can therefore be taken into account by the forecasting device 21 and converted by the setpoint mean 25 into a corresponding course of the setpoint , as indicated in Fig. 4 in the second box from above by lines 71 and 73 .

The invention is not restricted to the exemplary embodiments described, which are described in can be modified in many ways. This applies in particular with regard to the various components of the control device, the type of forecasting and the Type of deterministic determination of the target values.

Claims (14)

1. Method for the transmission of electrical power from a fluctuating energy processing power generator ( 5 ) to the power network ( 15 ) of an energy supply company ( 49 ), wherein differential powers between the power delivered by the power generator ( 5 ) and the power (P ₁ ) to the power grid ( 15 ) the total power (P ₅ ) supplied is fed or removed from an electrochemical store ( 27 ), comprising the following steps:
Forecasting the power that can be provided by the power generator ( 5 ) in future, preselected time intervals,
Definition of the preset time intervals (P ₃ ) assigned to the preselected time intervals and intended for delivery to the power grid ( 15 ) with defined, guaranteed courses taking into account the state of charge of the memory ( 27 ) and the outputs that can be output by the electricity generator ( 5 ),
Registration of the guaranteed performance curves and the associated time intervals before they begin with the energy supply company ( 49 ), and
Compliance with the registered power curves by regulating the total power (P ₅ ) delivered to the power grid ( 15 ) in such a way that the sum transferred at any preselected point in time from the power (P ₁ ) actually delivered by the power generator ( 5 ) and the power supplied to the memory ( 27 ) or withdrawn power (P ₄ ) always has the registered course. 2. The method according to claim 1, characterized in that the control provides a smoothed course of the total power (P ₅ ). 3. The method according to claim 1 or 2, characterized in that the forecasting of the power generator ( 5 ) in any preselected time interval power output taking into account the power output (P ₁ ) actually delivered by the power generator ( 5 ) in at least one time interval in the past. 4. The method according to any one of claims 1 to 3, characterized in that in the event that the current content of the memory ( 27 ) is not sufficient in any time interval to the power supply ( 15 ) deliverable total power (P ₅ ) with a guaranteed course, determine a total power (P ₅ ) to be supplied to the memory ( 27 ), assign this total power (P ₅ ) to a preselected future time interval and report it to the energy supply company ( 49 ) before it begins, and that the registered total power (P ₅ ) then in the preselected time interval from the power network ( 15 ) in the memory ( 27 ) is delivered. 5. The method according to claim 4, characterized in that the course with which the total power (P ₅ ) in the memory ( 27 ) is delivered to the energy supply company ( 49 ) reported and the delivery is then regulated accordingly. 6. The method according to any one of claims 1 to 5, characterized in that the Performance curves in the assigned time intervals are constant or linear over time increasing or decreasing. 7. Device for transmitting electrical power from a fluctuating energy processing power generator ( 5 ), comprising:
a transmission line ( 7 ) connecting the power generator ( 5 ) to the power network ( 15 ) of an energy supply company ( 49 ),
an electrochemical memory ( 27 ) connected to the transmission line ( 7 ) via a coupling point ( 9 ) for storing electrical energy,
a controllable lee and unloading device ( 39 , 61 ) connected between the coupling point ( 9 ) and the memory ( 27 ), which is set up to supply or supply the memory ( 27 ) with a power (P ₄ ) defined according to direction and amount remove,
a control device for the to the power supply (15) to be delivered total power (P ₅₎ with a to the loading and unloading apparatus (39, 61) connected to the controller (35), one connected to the controller (35) measuring means (41) for measuring the actual value of the total power (P ₅ ) supplied to the power grid ( 15 ), a setpoint determiner ( 25 ) which, together with the regulator ( 35 ), a unit ( 29 ) which determines the state of charge of the memory ( 27 ) and a forecasting device ( 21 ) for delivery is connected to data relating to the power that can be output by the power generator ( 5 ) at future, preselected time intervals, and which is set up to use the charge state of the memory ( 27 ) and the data to setpoint values (P ₃ ) for the total power assigned to the time intervals (P ₅ ) to determine which have defined, guaranteed courses,
and a registration device ( 47 ) connected to the target value determiner ( 25 ) and the energy supply company ( 49 ) for registering the guaranteed performance curves before the start of the time intervals assigned to them, the regulation of the total power delivered to the power network ( 15 ) in any preselected time interval ( P ₅ ) is carried out in such a way that the sum of the power (P ₁ ) actually output by the power generator ( 5 ) and the power (P ₄ ) supplied or withdrawn from the memory ( 27 ) always has the registered course. 8. The device according to claim 7, characterized in that the position of the time intervals is adapted to the capacity of the memory ( 27 ). 9. The device according to claim 8, characterized in that the power generator ( 5 ) is part of a wind turbine ( 1 ). 10. Device according to one of claims 7 to 9, characterized in that the power generator ( 5 ) has a transmitter ( 17 ) for the power output by this (P ₁ ) downstream and the forecasting device ( 21 ) is connected to the transmitter ( 17 ) . . 11. Device according to one of claims 7 to 10, characterized in that it has a wind measuring device connected to the forecasting device ( 21 ). 12. Device according to one of claims 7 to 11, characterized in that the forecasting device ( 21 ) is set up to process forecast data provided by a weather service. 13. Device according to one of claims 7 to 12, characterized in that the control device is set up such that the memory ( 27 ) is always a preselected minimum power can be removed. 14. The apparatus according to claim 13, characterized in that the registration device ( 47 ) is set up for bidirectional operation and the setpoint determiner ( 25 ) at a request of the energy supply company ( 49 ) in a predetermined time interval determines a maximum value corresponding to the minimum output.