DE102012215565A1 - Method for controlling system pool of current generators, involves providing environmental data prediction, particularly of weather prediction, for determined period, and creating feed-in power prediction of systems pool - Google Patents

Abstract

The method involves providing an environmental data prediction, particularly of a weather prediction, for a determined period, and creating a feed-in power prediction of the systems pool for the determined period on the basis of the environmental prediction. A maximum negative controlling power range is determined in recall period in the determined period through the systems pool on the basis of the feed-in power prediction. A controlling signal is generated depending on a recall controlling power and is transferred to the systems pool. An independent claim is included for a control device for controlling a system pool of current generators.

Description

The invention relates to a method for controlling a system pool of power generators, which have a fluctuating, predictable feed-in power, in particular of regenerative power generators, for providing a negative control power, in particular a negative minute reserve and / or secondary reserve.

The invention further relates to a control device for controlling a system pool of power generators, which have a fluctuating, predictable feed-in power, in particular of regenerative power generators, for providing a negative control power, in particular a negative minute reserve and / or secondary reserve.

The provision of control power is used to compensate for differences between supply and output in the power grid. Power generation capacities are offered on reserve power markets to transmission system operators. In this case, a distinction must be made between positive control power (energy supply by increasing the feed-in power or reducing load absorption) and negative control power (reducing the feed-in power or increasing load absorption).

Generators which have a fluctuating, predictable feed-in power, in particular regenerative power generators, are for example wind turbines, photovoltaic modules or photovoltaic systems or also water turbines of a tidal power station or underwater turbines for harvesting flow energy from water. The fluctuating, predictable feed-in power corresponds to the power feed of these power generators, which varies over time but is more or less accurately predictable based on different data. In particular, the increased use of regenerative power generators and the full supply of power generated by them into the grid increase the need for control power, in particular negative control power to cushion production spikes.

In Germany, access to standard benefit markets is regulated by prequalification procedures. The conditions of market participation of regenerative power generators were with the Amendment of the Renewable Energy Sources Act (EEG) as of 1 January 2012 newly regulated. In the future, power generation plants within the meaning of the EEG will, under certain conditions, be allowed to participate in the reserve power market.

However, in particular for regenerative power generators with fluctuating feed-in power, the provision of a negative control power is only possible, if at all, with considerable disadvantages. For example, considerations are known to make the control of a wind farm according to the performance of a non-regulated reference wind turbine of the park. However, this concept has the disadvantage that the reference wind turbine can not participate in the marketing of the control power, as it must always go on uncontrolled.

Furthermore, a reference value formation in the case of a simultaneous feed-in management at the wind farm is not possible because in this case usually all plants are subject to power limitation and the operation of a non-regulated reference wind turbine is not possible.

Also, a transmission of the power output of the reference wind turbine to the fictitious feed of the entire wind farm is possible only in dependence on the wind direction, the wind strength and the position of the reference wind turbine in the wind farm and subject to inaccuracies, especially due to different effects of air turbulence of the throttled running wind turbines on the wind farm the reference plant.

Such a concept for the provision of control power for wind farms is not only associated with significant disadvantages, but fails for other regenerative power generators such as photovoltaic systems: In a conventional photovoltaic system configuration, for example, the operation of a reference system is not possible because the reference photovoltaic module would have to have a separate inverter in order to identify a reference yield.

It is therefore an object of the present invention to provide a method and a control device for controlling a system pool of power generators with a fluctuating, predictable generating gear, which provides an improved provision of a negative reserve power, in particular a negative minute reserve and / or secondary reserve allow. In particular, it is an object of the present invention to provide a method and a control device for controlling a system pool of power generators, in particular regenerative power generators, which reduce or eliminate one or more of the mentioned disadvantages.

• – Bereitstellen einer Umweltdatenprognose, insbesondere einer Wetterprognose, für einen bestimmten Zeitraum,
• – Erstellen einer Einspeiseleistungsprognose des Anlagenpools für den bestimmten Zeitraum auf Basis der Umweltdatenprognose,
• – Ermitteln einer maximalen negativen Regelleistung, die in einem Abrufzeitraum in dem bestimmten Zeitraum durch den Anlagenpool bereitgestellt werden kann, auf Basis der Einspeiseleistungsprognose,
• – Erzeugen eines Regelsignals in Abhängigkeit einer Abrufregelleistung und Übertragen des Regelsignals an den Anlagenpool,
• – Reduzieren der Einspeiseleistung des Anlagenpools in Höhe der Abrufregelleistung in einem Aktivierungszeitraum durch Herabregelung mindestens einer Gruppe der Stromerzeuger des Anlagenpools,
• – Erbringen einer Abrufeinspeiseleistung, die gegenüber der Einspeiseleistungsprognose um die Höhe der Abrufregelleistung reduziert ist, für den Abrufzeitraum,
• – Erhöhen der Einspeiseleistung des Anlagenpools in Höhe der Abrufregelleistung in einem Deaktivierungszeitraum durch Aufhebung der Herabregelung der mindestens einen Gruppe der Stromerzeuger des Anlagenpools.

This object is achieved by a method for controlling a system pool of power generators having a fluctuating, predictable feed-in power, in particular of regenerative power generators, for providing a negative control power, in particular a negative minute reserve and / or secondary reserve, comprising the steps:

• Providing an environmental data forecast, in particular a weather forecast, for a specific period,
• - create a feed-in forecast of the investment pool for the given period on the basis of the environmental data forecast,
• Determining a maximum negative control power that can be provided by the asset pool in a retrieval period in the specified period, based on the feed-in performance forecast,
• Generating a control signal as a function of a demand control power and transmitting the control signal to the plant pool,
• - reducing the feed-in capacity of the system pool in the amount of the call-up control power in an activation period by reducing at least one group of the power generators of the system pool,
• Providing a polling feed-in power, which is reduced by the amount of the polling control power compared to the feed-in power forecast, for the polling period,
• - Increase the feed-in capacity of the investment pool in the amount of retrieval control power in a deactivation period by canceling the down regulation of the at least one group of power generators of the investment pool.

The method according to the invention is based on the finding that the feed-in capacity of plant pools can be predicted very accurately on the basis of environmental data forecasts, in particular weather forecasts. The accuracy of the prediction of the feed-in capacity of a plant pool on the basis of an environmental data forecast can be significantly higher than the determination of an energy yield of a plant park corresponding to a reference plant. The method according to the invention therefore envisages using the feed-in forecasts determined on the basis of environmental data forecasts before and in particular at the time of the control power output in order to derive from this what portion of the feed-in power can be offered on the market as a negative control power and how the feed-in power can be reduced in the case of Over the course of time, control service calls must be made.

The generation of a feed-in forecast of the investment pool is done for a certain period of time for which a corresponding environmental data forecast is available. For the generation of the feed-in performance forecast on the basis of the environmental data forecast, historical information about the feed-in capacity under the respective environmental, in particular weather conditions, is usually used. The best possible quality of the feed-in performance forecast on the basis of the environmental data forecast is advantageous and can be improved, in particular, by combining a large number of, in particular regenerative, power generators and, in particular, by combining a plurality of power plants, each with a large number of, in particular regenerative, power generators to form a system pool ,

A system pool is a combination of, in particular regenerative, power generators or power generation systems, which are preferably combined in terms of communication technology. A plant pool can be a single plant park with a plurality of, in particular regenerative, power generators. Alternatively, a plurality of plant parks, each with a plurality of, in particular regenerative, power generators can be combined in one investment pool. As a technical unit within the meaning of the pre-qualification conditions and the framework contract for the provision of reserve power, this is understood to mean a plant park or a pool of facilities. However, the method according to the invention is in principle also suitable for individual systems.

The method according to the invention can be used for all types of negative control power supply that are currently being tendered by transmission system operators in Germany, in particular primary control power, secondary control reserve and tertiary control power, also referred to as minute reserve power.

The provision of a control power may include creating an offer of a control power, offering a control power, providing and / or providing a control power.

The forecast feed-in over a certain period of time serves to determine the maximum available negative control power during this period. The maximum negative control power corresponds to the feed-in power forecast, in which case all power generators would be shut down. The maximum available negative control power can be determined for a polling period that is less than or equal to the specified time period for which the feed-in power forecast was created. The particular period for which the feed-in performance forecast was created may thus include multiple fetch periods each having different maximum negative control powers. This maximum negative control power can be offered on a reserve power market.

If a negative control power designated as a call-off service is called up in a call-off period, the feed-in power is corresponding to reduced negative control power. For this purpose, the feed-in capacity of the system pool is first lowered in an activation period, by downsizing or throttling at least part of the power generators of the system pool so that they provide less or no more power. All power generators of the system pool can be downsized. It is also possible to down-regulate all power generators of one or more plant parks which are combined in one system pool. It is also possible to control only part of the generators of one or more plant parks or the plant pool. The activation period is required to implement this deregulation and may, for example, be 15 minutes for a retrieval period of one hour. At the end of the polling period, the down-regulated generators are released again and the feed-in power is increased by the retrieved negative control power. This deactivation period, in which the down regulation is canceled, is also, for example, 15 minutes for an exemplary polling period of one hour.

In the time between the end of the activation period and the beginning of the deactivation period, a feed-in power is generated which corresponds to the course of the feed-in performance forecast that was created at the latest at the time of the control power demand in this period, but is reduced by the level of the demand control power.

In order to realize this reduction and subsequent increase of the feed-in power as well as the intervening provision of the polling feed-in power, a control signal is generated which depends on a polling control power, i. A combination of polling period and amount of a negative control power, as well as produced on presentation of the feed-in performance forecast and transmitted to the investment pool. On the basis of this control signal, the power generators of the system pool can then be controlled in such a way that the desired reduction of the feed-in power, provision of the call-in feed power and subsequent increase of the feed-in power can be realized.

Preferably, the polling control power is constant over the polling period. With a polling period of one hour, the offered maximum negative control power would thus correspond to the minimum of the feed-in power forecast in the concrete polling period. The shorter the polling periods are selected, the more negative control power can be offered, since only the respective minimums of the polling periods, but not the total minimum of the feed-in power forecast over the sum of the polling periods limit the maximum negative control power.

The inventive method eliminates the operation of a reference system, i. For the marketing of a pool of investment in the market for control power, the provision of one or more reference installations is not required, so that all generators of a pool of facilities can make a contribution to the provision of control services.

This makes it no longer necessary to record the dependence of the energy yield of a reference plant and the corresponding energy yield of the further power generators of the plant park or plantpoos. In particular, it is not necessary to record the current yields, for example of a reference wind energy plant, as a function of the wind strength and wind direction. The inaccuracy associated with controlling a system pool in accordance with the current yield of a reference installation can also be significantly improved by the method according to the invention, in particular when the application is extended to a geographically extensive area. In addition, photovoltaic systems are also able to provide negative control power by the method according to the invention without having a photovoltaic module with a separate inverter.

The method according to the invention also has the advantage that the reserve power can be called up and the system pool can be adequately controlled even if the power management system of a power grid operator precedes or coincides, provided that the feed-in management does not force complete shutdown of the power generators of the system pool and the level the retrieval control power is lower than the feed-in power reduced due to the feed-in management.

It is particularly preferred that, after the step of generating a control signal and before the step reducing the feed-in power, the step generating an updated feed-in forecast of the turbine pool for the specific period is performed on the basis of an updated environmental data forecast and the retrieval feed-in power provided for the polling period is over the updated feed-in power forecast the amount of polling control power is reduced. This feature of the method has the advantage that by updating the environmental data forecast and the resulting feed-in forecast at the time of the control power call, the accuracy of the feed-in power prediction can be significantly increased, in particular compared with the determination of an energy yield of a plant park corresponding to a reference installation.

• – der Schritt Bereitstellen einer Umweltdatenprognose, insbesondere einer Wetterprognose, für einen bestimmten Zeitraum das Bereitstellen von parkspezifischen Umweltdatenprognosen umfasst, und/oder
• – der Schritt Erstellen einer Einspeiseleistungsprognose des Anlagenpools das Erstellen von parkspezifischen Einspeiseleistungsprognosen, vorzugsweise auf Basis von parkspezifischen Umweltdatenprognosen, umfasst, die vorzugsweise zu einer Einspeiseleistungsprognose des Anlagenpools zusammengefasst werden, und/oder
• – der Schritt Ermitteln einer maximalen negativen Regelleistung das Ermitteln von parkspezifischen maximalen negativen Regelleistungen umfasst, die vorzugsweise zu einer maximalen negativen Regelleistung des Anlagenpools zusammengefasst werden, und/oder
• – der Schritt Erzeugen eines Regelsignals und Übertragen des Regelsignals an den Anlagenpool die Erzeugung von parkspezifischen Regelsignalen und deren Übertragen an den jeweiligen Anlagenpark umfasst, und/oder
• – der Schritt Reduzieren der Einspeiseleistung des Anlagenpools in Höhe der Abrufregelleistung in einem Aktivierungszeitraum durch Herabregelung mindestens einer Gruppe der Stromerzeuger des Anlagenpools das Reduzieren der parkspezifischen Einspeiseleistungen eines oder mehrerer der Anlagenparks in Höhe der Abrufregelleistung in einem Aktivierungszeitraum durch Herabregelung mindestens einer Gruppe der Stromerzeuger des jeweiligen Anlagenparks umfasst, und/oder
• – der Schritt Erbringen einer Abrufeinspeiseleistung, die gegenüber der Einspeiseleistungsprognose um die Höhe der Abrufregelleistung reduziert ist, für den Abrufzeitraum das Erbringen von parkspezifischen Abrufeinspeiseleistungen, die gegenüber der jeweiligen parkspezifischen Einspeiseleistungsprognose um die Höhe der Abrufregelleistung reduziert sind, umfasst und die vorzugsweise zu einer Abrufeinspeiseleistung des Anlagenpools zusammengefasst werden, und/oder
• – der Schritt Erhöhen der Einspeiseleistung des Anlagenpools in Höhe der Abrufregelleistung in einem Deaktivierungszeitraum durch Aufhebung der Herabregelung der mindestens einen Gruppe der Stromerzeuger des Anlagenpools das Erhöhen der parkspezifischen Einspeiseleistungen des einen oder der mehreren der Anlagenparks in Höhe der Abrufregelleistung in einem Aktivierungszeitraum durch Aufhebung der Herabregelung der mindestens einen Gruppe der Stromerzeuger des jeweiligen Anlagenparks umfasst.

In a preferred embodiment, the investment pool comprises one, two or more plant parks, each with a plurality of power generators, in particular a plurality of regenerative power generators. This embodiment is also characterized in that

• The step of providing an environmental data forecast, in particular a weather forecast, for a certain period comprises the provision of park-specific environmental data forecasts, and / or
• The step of generating a feed-in performance forecast of the investment pool comprises the generation of park-specific feed-in performance forecasts, preferably based on park-specific environmental data forecasts, which are preferably combined into a feed-in performance forecast of the investment pool, and / or
• The step of determining a maximum negative control power comprises determining parking-specific maximum negative control power, which are preferably combined into a maximum negative control power of the facility pool, and / or
• The step of generating a control signal and transmitting the control signal to the system pool comprises the generation of park-specific control signals and their transmission to the respective system park, and / or
• The step of reducing the feed-in capacity of the system pool at the level of the feed-in control power in an activation period by downsizing at least one group of the power generators of the system pool, reducing the park-specific feed-in capacities of one or more of the system parks in the amount of polling control power in an activation period by down-regulation of at least one group of the power generators of the respective ones Includes plant parks, and / or
• The step of providing a polling feed-in power reduced from the feed-in power forecast by the amount of polling control power, for the polling period comprises providing park-specific polling feed-in power reduced from the respective park-specific feed-in power forecast by the amount of polling control power, and preferably to a polling infeed power of the Pooled assets are pooled, and / or
• The step of increasing the feed-in capacity of the system pool in the amount of the demand control power in a deactivation period by abolishing the down regulation of the at least one group of the power generators of the plant pool, increasing the park-specific feed-in capacities of the one or more of the power plants in the activation control period by canceling the down regulation which comprises at least one group of the power generators of the respective plant park.

This embodiment ensures that, when combining two or more plant parks, each with a plurality of, in particular regenerative, power generators to a plant pool, the various plant parks can be controlled differently. Furthermore, park-specific data can also be used and park-specific features taken into account. In particular, park-specific environmental data can be used, which have a higher accuracy for geographically large investment pools for the individual investment parks. Furthermore, the historical data for determining feed-in performance forecasts on the basis of environmental data forecasts, for example, are preferably also determined and used in a park-specific manner. In this way, the advantages of the most accurate, park-specific forecasting and parking-specific control of the feed-in power can be combined with the higher accuracy or higher available maximum negative control power given in a summary of several asset pools to a pool.

It is also preferred that the preferably also performed step of creating an updated feed-in performance forecast of the investment pool for the specific period on the basis of an updated environmental data forecast, the creation of park-specific updated feed-in forecasts, preferably based on park-specific updated environmental data forecasts includes.

In particular, it is further preferred that the feed-in power forecast of the system pool and / or the maximum negative control power for the specific period be subdivided into time intervals with constant values within a time interval, a time interval preferably having a duration of one hour or less, in particular a duration of 15 minutes or less. A time interval can also be called a time slice

The specific period for which the feed-in power forecast and the maximum negative control power are determined is preferably subdivided into smaller time intervals or time intervals. A time interval may have a duration of, for example, an hour, a half hour, or a quarter of an hour. Likewise, periods may be 5 or 10 minutes or integer multiples thereof. In particular, a time interval may also be one minute or less. The time intervals are preferably chosen so that the specific period and / or the retrieval period amount to an integer multiple of the time intervals.

Within the time intervals, preferably constant values for the feed-in power forecast, the maximum negative control power and / or the call-in feed power are used. As a constant value, for example, the mean value or the minimum value during the time interval can be set. In particular, for the offer of a maximum negative control power, it is preferable to set the minimum value within a time interval as a constant value.

When retrieving a control power, the retrieval infeed power follows the infeed power forecast. Thus, if the feed-in power forecast is divided into time intervals each having constant values, the fetch feed-in power in the fetch period is preferably also provided with constant values in the time intervals.

During the activation and / or the deactivation period, which are preferably also an integer multiple of the time intervals, but as shown above, a reduction or cancellation of the down regulation of power generators instead, so that no constant, but a variable feed-in performance is provided.

In one embodiment, the determined period of the environmental data forecast and the feed-in performance forecast based thereon is a 24-hour period, in particular for a following day.

For example, so-called "day-ahead forecasts" are used to indicate feed-in schedules during this period. The provision of the polling feed-in power is set in this embodiment by maintaining a constant power difference corresponding to the level of the polling control power to the last logged-in timetable in the polling period. This last notified timetable is usually the spot market marketing timetable based on a day-ahead forecast or the most recent intraday timetable. These schedules are usually available anyway and thus require no separate effort for their creation. This embodiment of the method also has the advantage of high transparency by coupling to the usual commercial processes and the schedules used there. A transmission system operator is aware of the setpoint behavior of the system pool in advance via the timetable, for example via the balancing group schedules, and not only at the time of retrieval.

In a further embodiment, a current feed-in forecast based on an environmental data forecast current at a call-off time for the call-off period is generated for the provision of the call feed-in power, and the call feed power is reduced compared to the current feed-in power forecast by the level of the call control power.

In this embodiment, at the time when a polling control power is retrieved, a so-called short-term forecast is prepared on the basis of environmental data forecasts current at that time. The short-term forecasts have a significantly higher accuracy compared to a day-ahead forecast because they are based on more recent environmental data forecasts and, in addition to the historical feed-in information of the investment pool, preferably also include the actual output of the investment pool. Thus, compared to a day-ahead prediction, which is based on an environmental data forecast of the previous day, much more up-to-date data, in particular weather data, are used, with which the environmental data forecast for this shorter period is also much more accurate. As a result, the calculated feed-in performance forecast usually has a significantly higher accuracy than the day-ahead forecast of the notified timetable. By this method, the reserve power delivery is based on the best information available at the time of retrieval.

An advantage of this embodiment is, in particular, that the increase of the feed-in power at the end of the control power call in the deactivation period with a higher security can be done with an increase of the feed-in power by the full amount of the control request power. This power swing at the end of the RLR can not necessarily be guaranteed with a less accurate prediction. Further, the likelihood of underachieving the required power is lower in this preferred embodiment. The generation of the feed-in performance forecast at the beginning of the control service call therefore offers greater assurance of meeting the criterion of full power increase at the end of a control service call since unforeseen changes in the basic conditions, such as weather influences, have less impact on forecasting quality.

Further, it is preferable that the generated feed-in power forecast of the asset pool for the given period of time is a secured feed-in power forecast which is exceeded with a certain probability of an actual value, preferably with a probability of 95 out of 98 percent.

In order to ensure that an offered negative control power can actually be provided during the retrieval period, a confidence interval is determined for the infeed power forecast, which indicates which feed-in power can be provided with which probability as a function of the feed-in forecast. For example, such a so-called assured feed-in power is determined as the power that is exceeded with a 95 percent or 98 percent certainty from an actual feed-in power value.

In a further embodiment of the method, it is preferred that the transmission of the control signal to the system pool takes place via a current interface, wherein a desired feed-in power value is preferably transmitted to the system pool with the current strength of the control signal.

As a control signal, a current signal can preferably be used, which indicates by its strength, which target active power is to be provided as retrieval infeed power.

It is advantageous that an existing, uniform power interface can be used for this purpose. Usually, such a signal is received by a central computer of a system pool or plant and transferred from there to the individual power generator. Preferably, the power interface may be connected, for example by a DSL or UMTS connection, to a transmission system operator or a reserve power pool operator.

In particular, it is preferred that a feed-in management signal is transmitted to the system pool or can be transmitted via the current interface. The use of the power interface for both the feed-in management and the control signal to provide a control power has the advantage that feed-in management and control power delivery can occur simultaneously, since it is ensured that in the case of feed management and during the retrieval of a control power, the feed-in signal is passed.

The work availability of a plant pool for providing a control power, in particular a minute reserve pool of wind farms, may be below 100% due to unavailability of communication links and / or forecast inaccuracies. Depending on the safety level of the feed-in performance forecast, e.g. a wind power forecast, the work availability can be about 99%. One possibility for securing this "residual risk" can be, for example, through a part of the investment pool, for example a wind farm, which does not belong to the portfolio offered. The size that this collateral pool should have can be determined by the confidence range of the offering pool of assets. Alternatively, collateral could be provided through taxable renewable energy, such as biomass plants.

In particular, it is preferred that the power generators are wind turbines and the environmental data forecast includes a wind forecast, in particular a forecast of wind direction and / or wind strength. On the basis of this environmental data forecast, a wind power prognosis and / or a feed-in performance prognosis of the wind energy plants is then preferably created.

A first alternative is that the power generators are photovoltaic systems and the environmental data forecast comprises a global radiation prognosis, in particular a prognosis of irradiation duration and / or irradiance. On the basis of this environmental data forecast, a feed-in performance forecast of the photovoltaic systems is then preferably created.

The global radiation forecast is a prediction of the global solar radiation arriving on the earth's surface, in particular a prediction of the solar radiation impinging on a horizontal receiving surface at the earth's surface.

Another alternative is that the power generators are water turbines and the environmental data forecast includes a tide forecast, in particular a forecast of a tidal range.

Hydro turbines are used for example in tidal power plants, in which the turbines are preferably working in two opposite directions of flow to be fed at tide of inflowing water and at low tide of outflowing water.

A further alternative is that the power generators are underwater turbines and the environmental data forecast comprises a flow forecast, in particular a forecast of flow direction and / or flow intensity. On the basis of this environmental data forecast, a feed-in performance prognosis of the underwater turbines will be created.

Underwater turbines are anchored, for example, on the seabed and driven by currents in the water. Preferably, the underwater turbines are rotatably mounted about a vertical axis to track flow direction changes can. Furthermore, the underwater turbines are preferably installed in run-of-river power plants in rivers.

According to a further aspect of the invention, the object mentioned at the outset is achieved by a control device for controlling a system pool of power generators having a fluctuating, predictable feed-in power, in particular of regenerative power generators, for providing a negative control power, in particular a negative minute reserve and / or secondary reserve, characterized in that the control device is adapted, on the basis of a provided environmental data forecast, in particular a weather forecast, for a certain period of time, to create a feed-in performance forecast of the investment pool for the determined period of time, based on the feed-in forecast, a maximum negative control benefit in a polling period in the be determined by the pool of equipment to determine determined to generate a control signal in response to a polling control power and the control signal to the plant Po ol, reduce the feed-in capacity of the plant pool at the call-up control power in an activation period by downsizing at least one group of the power generators of the plant pool, a call-in feed power reduced from the feed-in power forecast by the level of the polling control power, for the polling period by the power generators of the plant pool in a deactivation period, by removing the down regulation of the at least one group of the power generators of the installation pool, and to increase the feed-in capacity of the system pool in the amount of the demand control power. For the advantages, design variants and design details of the control device and its possible further developments, reference is made to the preceding description of the corresponding method features.

According to a further aspect of the invention, the object mentioned at the outset is achieved by the use of an environmental data forecast, in particular a weather forecast, for controlling a plant pool of power producers which have a fluctuating, predictable feed-in power, in particular regenerative power generators, for providing a negative power Control power, in particular a negative minute reserve and / or secondary reserve, according to one of the methods described above or one of its further training.

Preferred embodiments of the invention will be described by way of example with reference to the accompanying figures. Show it:

1 : a day-ahead forecast of seven consecutive days for a wind farm investment pool;

2 : a graphical representation of a offered maximum negative control power;

3 : a graph of the dependence of the offered power on the size of a wind farm pool;

4 : a graphic representation of a control service call based on the last registered timetable;

5 : graphic representation of a control service call based on a short-term prognosis prepared; and

6 : A graph comparing the forecast inaccuracies of day-ahead forecasts and short-term forecasts.

The following embodiments are related to a plant pool with wind turbines as power generators, which in particular belong to several wind farms, which are combined to form a pool of facilities, and should provide a negative minute reserve power (MRL). The exemplary embodiments can also be modified accordingly for another negative control power provision, in particular a secondary reserve power.

In the illustrated embodiment, the offer is made to provide negative minute reserve power based on a wind power forecast on the day before the day of delivery. 1 shows the day-ahead forecasts of seven consecutive days. On the x-axis the time is shown in days and on the y-axis the power in percent of the installed power. line 1 indicates the feed-in performance forecast. In addition to the forecast, a confidence interval is determined which indicates the assured performance as a function of the predicted performance. This assured performance is determined with a given significance level of, for example, 95% or 98%. The lines 2 and 3 show the predictions for the assured performance, which with 95% probability (line 2 ) or with 98% probability (line 3 ) from the actual value (line 4 ) will be exceeded.

2 shows on the x-axis for a day four-hour time intervals and on the y-axis, the power in percent of rated power. The line 10 represents the feed-in forecast and the line 20 the assured feed-in performance forecast, which will be exceeded by 95% of the actual value. Based on the line 20 Within the four-hour time intervals, constant values are formed which correspond to a respective minimum value of the line 20 within a time interval. This line 30 represents the maximum negative balancing power that can be offered on the market. The wind power to be offered as a negative minute reserve 30 thus results from the minimum secured services per time interval.

The maximum negative minute reserve power that can be marketed according to this principle depends largely on the geographical extent of the investment pool. The greater the spatial distribution of the wind farms of the investment pool, the better the accuracy of the prediction due to balancing effects. As in 3 In the case of a fixed confidence level, the secured capacity increases significantly with the pool size. In 3 the power in percent of installed power is given on the x-axis and the frequency in percent on the y-axis. The performance range of the prediction lies between 45 and 55%. The line 110 of the 3 corresponds to a single wind farm, the line 120 a small investment pool of wind farms with an extension of 100 km and the line 130 a large investment pool of several wind farms with an extension of 350 km. The bar mark 140 indicates the 5% quantile of each wind farm, the dashed line 150 the 5% quantile of the small investment pool and the dashed line 160 the 5% quantile of the large pool. At a power output of 50% of the installed power, the minute reserve power supply of a single wind farm (line 110 ) about 17% of the installed capacity, with a small pool of about 100 km extension (line 120 ), the guaranteed capacity is already over 20% and with a large pool of about 350 km expansion 35% and more are achieved.

Already for a small pool, negative minute reserve service offers can be made for approximately 32% of the time intervals of a year. The average supply size is 22% of the installed wind capacity of the investment pool. The work offered in connection with minute reserve power amounts to 31% of the annual energy yield of the pool. On Mondays and days after holidays, however, there is an increased forecast uncertainty.

In the case of a call for negative minute reserve, the individual wind farms of a system pool are individually controlled via their wind farm computers by the operator of a minute reserve pool, and a target specification of the power value is transmitted via the control signal. This power value is dynamically adjusted so that the minute reserve performance in the required corridor ranges from 100 to 120% of the marketed minute reserve power. In a first variant, the provision of the minute reserve service takes place on the basis of the last registered trading timetable, as in 4 shown.

When calling up a control power, a constant power difference to the last registered timetable should be kept. As a rule, the last notified timetable is the marketing timetable reported for the spot market, ie the timetable is based on a day-ahead forecast. If the investment pool of wind farms is also marketed intraday, the last announced timetable corresponds to the most recent intraday timetable. In 4 For example, x-axis represents time in quarter-hour intervals, and y-axis represents power in megawatts. With line 210 the rated power is given.

The difference in performance to the last registered timetable is composed of the retrieved minute reserve power and the difference between the instantaneous actual infeed and the timetable at the time of retrieval. The registered timetable is with 220 denotes the line 230 represents the actual feed, the dotted line 240 would correspond to the actual feed without regulation. In 4 will be in the period 290 a 5 MW minute reserve service call 290 shown.

The investment pool becomes the start of the call in an activation period 270 to the recalled control power 201 throttled in its feed-in performance. The reference is the active power mean value, ie the average power output of the system pool 260 , the last recorded quarter hour.

In the course of the call, the system pool is always throttled in its feed-in capacity in such a way that compared to the registered timetable, an average active power difference in the amount of the marketed control reserve retrieved plus the schedule deviation at the time of retrieval occurs every quarter of an hour. Between the activation period 270 and the deactivation period 280 follows the reduced performance on call, the demand control power 250 , the last announced timetable 220 in the 15-minute grid of the time intervals, whereby this schedule is lowered by the call and the forecast deviation existing at the time of the call. In a deactivation period 280 the feed-in power will be around the value 202 raised again. At the point of power increase in the deactivation period 280 Especially at individual wind farms due to the inaccuracy of the prediction is the risk that the power stroke 202 not completely achieved.

In another variant, the in 5 is shown, the standard service receipt takes place on the basis of a short-term forecast prepared at the beginning of the call. In 5 On the x-axis again a period in 15-minute time intervals is shown and plotted on the y-axis, the power in megawatts. In the period 390 again a 5 MW Minutes Reserve retrieval. line 310 represents the nominal power and line 320 the announced timetable. line 330 denotes the actual feed and the dotted line 340 the actual supply without regulation. Opposite the 4 Added to this is the current short-term forecast 321 to which the reduced power on call, the polling control power 350 , is reduced. With 360 the averaged actual feeds of the last quarter of an hour are shown again. The shortest-term prognosis forms the reference corridor for the subsequent throttling of the investment pool over the call period, ie a constant performance difference is maintained at the time of the call for the shortest-term forecast, thus a mean active power difference equal to the call control performance in each quarter-hour time interval is always maintained compared to the short-term forecast. The investment pool becomes the call start in the activation period 370 around the marketed call-up control power in the amount of the value 301 throttled in its feed. In the deactivation period 380 there is an increase in the feed-in power by the value 302 ,

In the method according to 5 When a control service is called up, a short-term forecast is created which is usually created only for the purpose of the control service call and does not enter the trading process. Due to the up-to-date calculation with current feed-in values, historic plant data and especially current weather information, the short-term forecast is considerably more accurate than, in particular, the previous day forecast. Another advantage of this method is that the power swing at the end of the polling period can be significantly better ensured.

The technical implementation for the control of a wind farm can be done via various interfaces and transmission paths. An easily feasible and therefore advantageous possibility is the use of the uniform power interface, which is also used for feed-in management of wind farms of greater power, in particular of more than 2 megawatts. This can also be ensured in an advantageous manner that in the case of feed management, the associated signal is passed through. Due to the current strength of the signal, the wind farm computers transmit unambiguous active power setpoints, which in turn are transmitted by the wind farm computer to the individual wind turbines. The power interface may be e.g. be connected through a DSL or UMTS connection to a minute reserve pool operator.

6 gives an overview of the typical prediction errors of different forecasts. On the x-axis are a single park 401 , a small investment pool 402 as well as a large investment pool 403 Plotted on the y-axis is the root mean square error (RMSE) normalized to the installed power in percent. With 410 In each case the short-term forecasts or short-term forecasts are shown, with 420 the day-ahead forecasts. It becomes clear that on the one hand the investment pool size has a positive influence on the prediction accuracy and on the other hand the short-term forecast compared to the day-ahead forecast is much more accurate.

QUOTES INCLUDE IN THE DESCRIPTION

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Cited non-patent literature

• Amendment of the Renewable Energy Sources Act (EEG) as of 1 January 2012 [0005]

Claims (14)

Method for controlling a system pool of power generators, which have a fluctuating, predictable feed-in power, in particular of regenerative power generators, for providing a negative control power, in particular a negative minute reserve or secondary reserve, comprising the steps: Providing an environmental data forecast, in particular a weather forecast, for a specific period, - create a feed-in forecast of the investment pool for the given period on the basis of the environmental data forecast, Determining a maximum negative control power that can be provided by the asset pool in a retrieval period in the specified period, based on the feed-in performance forecast, Generating a control signal as a function of a demand control power and transmitting the control signal to the plant pool, - reducing the feed-in capacity of the system pool in the amount of the call-up control power in an activation period by reducing at least one group of the power generators of the system pool, Providing a polling feed-in power, which is reduced by the amount of the polling control power compared to the feed-in power forecast, for the polling period, - Increase the feed-in capacity of the investment pool in the amount of retrieval control power in a deactivation period by canceling the down regulation of the at least one group of power generators of the investment pool. Method according to the preceding claim, characterized in that the plant pool comprises one, two or more plant parks, each with a plurality of power generators, in particular a plurality of regenerative power generators, and - the step providing an environmental data forecast, in particular a weather forecast, for a certain period of time Providing parking-specific environmental data forecasts, and / or the step of generating a feed-in forecast of the investment pool comprises generating park-specific feed-in performance forecasts, preferably based on park-specific environmental data forecasts, which are preferably combined into a feed-in performance forecast of the investment pool, and / or the step of determining maximum negative control power includes determining park-specific maximum negative control power, preferably merging to a maximum negative control power of the pool of facilities and / or the step of generating a control signal and transmitting the control signal to the system pool comprises the generation of park-specific control signals and their transmission to the respective system park, and / or the step reducing the feed-in capacity of the system pool in the amount of the control system power in one Activation period by downgrading at least one group of power generators of the pool of installations comprising reducing the park-specific feed-in capacities of one or more of the power plants in the amount of polling control power in an activation period by derating at least one group of the power generators of the respective plant park, and / or the step of providing a polling feed-in power is reduced by the level of polling control power compared to the feed-in power forecast, for the polling period, the provision of park-specific polling feed-in power compared to the respective park-specific feed-in the step of increasing the feed-in capacity of the system pool in the amount of the demand control power in a deactivation period by canceling the down regulation of the at least one group of power generators of the Plant pools, the increase of the park-specific feed-in services of the one or more of the plant parks in the amount of retrieval control power in an activation period by removing the down regulation of the at least one group of power generators of the respective plant. Method according to one of the two preceding claims, characterized in that the feed-in power prognosis of the system pool and / or the maximum negative control power for the specific period and / or the retrieval period are divided into time intervals with constant values within a time interval, wherein a time interval is preferably a duration of one hour or less, in particular has a duration of 15 minutes or less. Method according to one of the preceding claims, characterized in that the determined period of the environmental data forecast and the feed-in forecast based thereon is a 24-hour period, in particular for a following day. Method according to one of the preceding claims, characterized in that for the provision of the call-up feed-in power, a current feed-in power forecast based on an environmental data prognosis current at a call-off time is created for the polling period and the polling feed-in power is reduced compared to the current feed-in forecast by the amount of polling control power. Method according to one of the preceding claims, characterized in that the generated feed-in performance forecast of the investment pool for the specific period of time is a reliable feed-in performance forecast, which is exceeded by a certain probability of an actual value, preferably with a probability of 95 of 98 percent. Method according to one of the preceding claims, characterized in that the transmission of the control signal to the system pool via a current interface, wherein preferably with the current strength of the control signal, a desired feed-in power value is transmitted to the system pool. Method according to the preceding claim, characterized in that via the current interface and a feed management signal is transmitted to the system pool. Method according to one of the preceding claims, characterized in that the power generator wind turbines and the environmental data forecast includes a wind forecast, in particular a forecast of wind direction and / or wind strength. Method according to one of the preceding claims, characterized in that the power generators are photovoltaic systems and the environmental data forecasting comprises a global radiation prognosis, in particular a prognosis of irradiation duration and / or irradiance. Method according to one of the preceding claims, characterized in that the power generators are water turbines and the environmental data forecast includes a tide forecast, in particular a prognosis of a tidal range. Method according to one of the preceding claims, characterized in that the power generators are underwater turbines and the environmental data forecast comprises a flow forecast, in particular a forecast of flow direction and / or flow intensity. Control device for controlling a system pool of power generators, which have a fluctuating, predictable feed-in power, in particular regenerative power generators, for providing a negative control power, in particular a negative minute reserve and / or secondary reserve, characterized in that the control device is formed, - on the basis of a provided Environmental data forecast, in particular a weather forecast, for a certain period of time to produce a feed-in forecast of the investment pool for the specified period; - to determine a maximum negative control benefit that can be provided by the investment pool in a specific period of time based on the feed-in performance forecast; - to generate a control signal as a function of a demand control power and to transmit the control signal to the plant pool, - the feed-in capacity of the plant pool in the amount of the call-up control to reduce the output in a period of activation by reducing at least one group of the generators of the installation pool, - to have a polling feed-in power reduced by the level of the polling control power compared to the input power forecast for the polling period by the generators of the equipment pool, and - the input power of the equipment pool increase in the amount of the retrieval control power in a deactivation period by canceling the down regulation of the at least one group of power generators of the investment pool. Use of an environmental data forecast, in particular a weather forecast, for a certain period for controlling a plant pool of power producers having a fluctuating, predictable feed-in power, in particular regenerative power generators, to provide a negative control power, in particular a negative minute reserve and / or secondary reserve, according to one of preceding claims 1 to 12.

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