DE102018005967A1 - Procedure for monitoring compliance with feed-in conditions - Google Patents

Abstract

The invention relates to a method for monitoring compliance with feed conditions and to an arrangement (1) designed for this purpose and a corresponding set of computer program products. In the method, compliance with the feed conditions of a power network (1) is ensured by one or more power generation units (4, 5) feeding into it ) monitored by the steps: - Detection of the voltage and current per phase at the grid feed-in point of a power generation unit (4, 5) or a group (6) of power generation units (5) to form measurement time series; - Calculation of hash values for measurement time series; - Determination of evaluation quantities from measured value time series; - Adding the hash values and evaluation variables to a distributed ledger database; - Checking compliance with the feed-in conditions based on the evaluation variables in the distributed ledger database using a computer log depicting the feed-in conditions (16).

Description

The invention relates to a method for monitoring compliance with feed conditions and to an arrangement designed for this purpose and a corresponding set of computer program products.

With the advent of the use of regenerative energies such as wind and sun, the operation of energy networks for the distribution of the generated and fed electrical energy has changed. In the past, only a few conventional power plants fed the required energy into an energy network at a few points, whereby the operation of the power plants and the network was often in one hand, nowadays energy is used at many points in an energy network - which were originally not intended for this purpose of regular small power generation units compared to conventional power plants fed into the energy network, whereby the operators of the energy generation units generally do not also operate the energy network. These energy generation units can be, for example, photovoltaic systems, a single wind energy system or wind energy systems combined to form a wind farm.

The operator of the energy network is responsible for the availability and stability of the energy network. In order to achieve this, he can define conditions that the operators of energy generation units must meet in order to be able to feed energy into the energy network. These feed-in conditions, often referred to as “grid codes”, can determine how and / or to what extent the energy generation units must contribute to grid stability, how they must behave in the event of a fault in the grid and / or which external control commands by the Operators of the energy supply network in which time must be implemented.

Smaller disturbances in the network can generally be quickly compensated for in such a way that the stability of the network is generally preserved and no problems are to be expected, in particular, for the consumers connected to the network. If there is a major disturbance in the network, e.g. a voltage dip, a voltage increase, a frequency deviation, etc., which cannot be compensated for in the short term, this can lead to problems for consumers, but also for the components of the energy network itself, which are caused by a short-term failure to damage or destruction of the consumer or energy network components.

In these cases, detailed cause research is carried out for the reason for the fault, also due to possible claims for damages, whereby in this context the accusation may arise that an energy generation unit is causing the fault or, at least in the event of the fault, does not comply with the feed-in conditions Has.

In these cases, an expert is often called in, who tries to clarify compliance with the feed-in conditions at the time of the fault on the basis of data recorded by the energy generation unit and / or the energy supply network.

A disadvantage of this state of the art is the complex, lengthy and generally cost-intensive analysis by an expert. Another disadvantage is that corresponding reports are only subsequently requested and prepared regularly if a massive violation of the feed-in conditions is suspected or if damage has actually occurred. A violation of the feed-in conditions that is not significant in the case of minor faults, but which can lead to damage in the case of major faults, often remains undetected.

The object of the present invention is to create a method, an arrangement and a set of computer program products for monitoring the compliance with feed conditions, in which the disadvantages known from the prior art no longer occur or only to a reduced extent.

This object is achieved by a method according to the main claim, an arrangement according to claim 9 and a set of computer program product according to claim 10. Advantageous further developments are the subject of the dependent claims.

• - Erfassen der Spannung und Stromstärke je Phase am Netzeinspeisepunkt einer Energieerzeugungseinheit oder einer Gruppe von Energieerzeugungseinheiten zur Bildung von Messwertzeitreihen;
• - Berechnen von Hashwerten für Messwertzeitreihen;
• - Ermittlung von Bewertungsgrößen aus Messwertzeitreihen;
• - Hinzufügen der Hashwerte und Bewertungsgrößen zu einer Distributed-Ledger-Datenbank; und
• - Überprüfen der Einhaltung von Einspeisebedingungen anhand der Bewertungsgrößen in der Distributed-Ledger-Datenbank durch ein, die Einspeisebedingungen abbildendes Computerprotokoll.

Accordingly, the invention relates to a method for monitoring compliance with the feed-in conditions of a power grid by one or more power generation units feeding therein, with the steps:

• - Detection of the voltage and current per phase at the grid feed-in point of an energy generation unit or a group of energy generation units to form measured value time series;
• - Calculation of hash values for measured value time series;
• - Determination of evaluation variables from measured value time series;
• - adding the hash values and evaluation values to a distributed ledger database; and
• - Checking compliance with feed-in conditions on the basis of the evaluation variables in the distributed ledger database by means of a computer log depicting the feed-in conditions.

Furthermore, the invention relates to an arrangement comprising at least one energy generation unit which feeds into a power grid at a grid feed-in point, a detection module for detecting the voltage and current intensity per phase being provided at the grid feed-in point and the components of the arrangement being designed to carry out the method according to the invention.

The invention also relates to a set of computer program products, comprising program parts which, when loaded into a computer or into computers networked with one another, are designed to carry out the method according to the invention.

The invention has recognized that through detailed monitoring of the power fed in by a power generation unit or a group comprising a plurality of power generation units at a network feed-in point, and based on this, manipulation-proof processing of the measured values, reliable and extremely transparent for the respective operators of power generation units and power grids Determination of compliance with the feed-in conditions, a significantly simplified processing in the event of losses or damage due to deviations from the feed-in conditions is possible. The automation of the monitoring provided according to the invention also makes it possible to determine non-compliance with the feed-in conditions in the case of less critical network faults, in order to be able to remedy any malfunctions of the energy generation unit.

The basis for the method according to the invention is the detection of the voltage and current strength per phase at the grid feed-in point of an energy generation unit or else a group of energy generation units. In principle, these measured values can be recorded by suitable measuring devices of the energy generation unit that are regularly provided for control purposes. However, since these measured values are the basis for the later determination of compliance with the feed-in conditions and must be regarded as trustworthy by the parties involved, it is preferred - especially if the power grid does not have suitable measuring devices for validating the measured values recorded by the energy generation unit - if The detection of the voltage and current per phase at the grid feed-in point is carried out by a calibrated and / or lead-sealed detection module. The acquisition module can in particular be made available and operated by a jointly selected third party, so that the operators of the energy generation unit (s) and of the power grid trust the acquired measurement values.

The measured values result from the measured value time series, that is to say a time-dependent sequence of measured values which reflects the course of the measured variable. The measured value time series can have a fixed, predetermined length and can be lined up in such a way that, in the sequence, they give a continuous image of one or more measured values.

Also in order to keep the computation and storage effort, which will be explained in more detail below, as low as possible, it is preferred if a measured value time series is only formed when a network disturbance signal is present, preferably for the duration of the presence of the network disturbance signal. In other words, an actual measurement time series, which is subsequently processed, is only created if there is actually a fault in the network and this is indicated by a network fault signal. The network fault signal can be transmitted directly by the operator or the control center of the power grid, or the power generation unit or a detection module for detecting the voltage and current per phase at the grid feed-in point have means for detecting a grid fault based on the measured values and for generating a corresponding grid fault signal.

In order not only to record the feed-in behavior of the energy generation unit (s) immediately when a network fault signal is present, but also to record a defined period before and / or after, it is further preferred if the measured value time series is supplemented by measured values that unite one predefined time period before and / or after the presence of a fault signal was or will be recorded. In particular, since there is a certain delay between the actual occurrence of a network fault and the presence of a network fault signal, supplementing the measured value time series with measured values before the actual presence of the fault signal can ensure that both the moment at which the fault occurs and the feed-in before the fault occurs are recorded in the measurement time series. If the measured value time series is recorded by measured values for a period after the mains fault signal has ceased, the return of the energy generation unit (s) to the normal feed-in can also be recorded.

A hash value is calculated for each measurement time series - whether created continuously or only when required. A hash value is the result of a non-injective, preferably cryptographic, scatter value function, with which a fingerprint of the measured value time series that is as clear as possible is created. Using a corresponding hash value, the measured value time series can, if necessary and / or desired, be saved and archived separately from the hash values. Subsequent changes to a saved or archived measurement time series would lead to a different hash value when recalculated, which can be used to detect tampering with measurement time series.

The hash values for measured value time series can be calculated by the acquisition module that acquires the measured values. However, it is also possible for this module to make the measured values and / or measured value time series available to an external entity, which then calculates the hash values. In particular, it is possible for more than one instance to carry out the hash value calculation, the calculated hash values then being mutually validated. For example. the hash value calculation can be carried out both by a computer of the operator of the energy generation unit (s) and by a computer of the network operator.

Evaluation values are also determined from the measured value time series, on the basis of which compliance with the feed-in conditions can be checked. A possible evaluation parameter is, for example, the active power rate - that is, the change in the active power fed in over time - after a grid fault that caused a voltage breakdown has been remedied. In addition, compliance with characteristic curves and operating ranges, as specified by the feed-in conditions (e.g. with regard to reactive current dynamics and active power reduction when frequency increases), can be checked. It can also be checked whether the power generation unit switches off in good time in the event of significant network faults and / or whether minor network faults occur properly.

Comparable to the hash values, the evaluation parameters can be determined by the acquisition module for the measured values. Here too, however, it is possible for the evaluation variables to be carried out and mutually validated by several entities, for example the operator of the wind energy installation (s) and / or the power grid.

The calculated hash values of a measured value time series and the determined evaluation variables of the same measured value time series - but not the measured values of the measured value time series itself for reasons of storage space - are then added as a data record to a distributed ledger database. Distributed ledger databases are databases that are managed decentrally on networked computers and come to an agreement (consensus) on the sequence of database entries and changes. An example of such a distributed ledger database is the blockchain. A blockchain is a continuously expandable list of data records that are linked to one another in a tamper-proof manner using cryptographic methods. Each data record typically includes a cryptographically secure scatter value of one or more previous data records, a time stamp and the actual user data, in this case hash value and evaluation variables. The blockchain can also be managed and stored decentrally, which can further increase its security.

The use of the generally known distributed ledger technology, in particular blockchain technology, ensures that the hash values and evaluation variables can no longer be manipulated afterwards.

When adding the hash values and evaluation variables to the distributed ledger database or blockchain, a computer protocol depicting the feed-in conditions is preferably used at the same time to check compliance with feed-in conditions using the evaluation variables added or to be added to the distributed ledger database or blockchain. It is of course also possible for the check to be carried out before or after adding the hash values and evaluation variables. The However, checking at the same time as adding can be achieved directly using known smart contract technologies, which are considered to be tamper-proof, so that generally no additional tamper-evident precautions need to be taken when checking compliance with the feed-in conditions, as is the case with a separate upstream or downstream one Review might be the case.

The result of the check is preferably also stored in the distributed ledger database or blockchain and is therefore tamper-proof. In particular, if a smart contract technology is used, it is possible to save the result of the check immediately together with the underlying evaluation parameters and the associated hash value in a single data record.

The method according to the invention offers a tamper-proof verifiability of compliance with the feed-in conditions of a power grid by one or more power generation units feeding into it, in particular in the event of grid faults. It is only conceivable and possible that the operators of power generation unit (s) and / or power grids trust the final result of the method to such an extent that one or more experts usually check the feed-in behavior by an expert examination of the feed-in behavior Power generation units can be dispensed with in the event of a grid failure.

If a corresponding expert opinion is nevertheless requested, it can be checked on the basis of the hash value calculated and stored according to the invention that the operator actually presents the expert with the correct measured values recorded at a predetermined point in time, for example a network fault. Even in this case, the method according to the invention thus offers even greater security against manipulation.

In principle, it is also possible, for example, to monetarily reward compliance with the feed-in conditions or special requirements of the network operator. If this can be derived from the valuation variables, the reward can also be depicted automatically in the form of a smart contract.

Since the measured values at the grid feed-in point are used according to the invention, additional devices that are integrated into a wind farm's internal grid and can influence the feed-in of energy, such as STATCOMs or energy stores, are also recorded transparently, in particular in the case of wind energy plants combined to form a wind farm. In other words, to check compliance with the feed-in conditions, it is fundamentally irrelevant which devices are located behind the grid feed-in point and are actually active.

So that the determination of evaluation variables and the subsequent check of compliance with the feed-in conditions can be carried out with sufficient accuracy and reliability, it is preferred if the detection of the voltage and current strength per phase with a sampling rate of at least 1 kHz, preferably of at least 2 kHz, more preferably of at least 5 kHz. It has been shown that with appropriate sampling rates, a sufficiently precise picture of the actual situation at the grid entry point can be provided.

To explain the arrangement according to the invention and the set of computer program products according to the invention, reference is made to the above explanations. By using a set of computer program products, it can be seen that the individual computer program products of the set can be executed on different computers. This enables an efficient distribution and use of resources, especially if the computer program products are not exclusively executed on a computer.

The energy generation units are preferably wind turbines. A group of corresponding energy generation units is a wind farm.

• 1: eine zur Durchführung eines erfindungsgemäßen Verfahrens ausgebildete erfindungsgemäße Anordnung.

The invention will now be described by way of example with reference to an advantageous embodiment with reference to the accompanying drawings. It shows:

• 1 : an arrangement designed to carry out a method according to the invention.

In 1 is an arrangement according to the invention 100 shown. The arrangement comprises a power network 1 comprehensive local transmission network 2 and several local distribution networks connected to it 3 , Especially on the distribution networks 3 are various, not shown consumers, such as industrial companies, commercial companies and households connected.

The energy to be distributed through the power grid is generated by power generation units 4 . 5 provided. In addition to a conventional power plant 4 , which the generated energy directly into the transmission network 2 feeds, feed individually or in a wind farm 6 combined wind turbines 5 also energy into the power grid 1 on. Among other things due to the spatial proximity of the respective lines, they are often not fed into the transmission system 2 but rather in local distribution networks 3 , In the exemplary embodiment shown, the wind farm comprises 6 another energy storage 7 that together with the wind turbines 5 via an internal wind farm network 8th via a transformer and park control station 9 with the power grid 7 , especially a local distribution network 3 is connected.

The power grid 1 with the help of measuring stations and sensors (not shown) in a network monitoring and control center 10 supervised. The network monitoring and control center 10 is about data lines 11 directly or via a parking control station 9 with the individual power generation units 4 . 5 connected, and can make these specifications regarding the energy feed-in either directly from the energy generation units 4 . 5 implemented or initially from a parking control station 9 in individual specifications for the connected wind turbines 5 as well as the electricity storage 7 to be translated.

The duty of power generation units 4 . 5 Reacting to the corresponding requirements within a certain time is laid down in the feed-in conditions. In these feed-in conditions there are still provisions for the behavior of the power generation units 4 . 5 included in the event of a grid failure, even without explicitly specified by the power generation units 4 . 5 have to be implemented.

To check whether the wind turbine 5 or the wind farm 6 comprising several wind turbines 5 and a power storage 7 Comply with the feed-in conditions at the respective grid feed-in points 12 provided with which the voltage and current strength are recorded separately for each phase with a sampling rate of 5 kHz. The acquisition modules 12 are designed to use the measured values to detect network faults, for example due to a sudden massive drop in voltage, and to then generate a network fault signal. Optionally - like this for the wind farm 6 is shown - the acquisition modules 12 also via a data line 11 to the network monitoring and control center 10 be connected to receive network fault signals from there.

If a registration module 12 If there is a self-generated or external fault signal, the measured values currently being recorded are combined in a measured value time series. These are stored in a buffer in the acquisition module 12 stored measured values of the last 10 seconds before the input of the network fault signal added. The measured value time series is updated by 5 seconds until the mains fault signal disappears and beyond. This ensures that not only the feed-in behavior during the presence of a grid fault signal, but also the feed-in before the occurrence of the grid fault and after its clarification, including the respective transients, is recorded in the measured value time series.

If required, the measurement time series created in this way can be optionally sent to the acquisition module 12 connected data storage for later checking and archiving. In any case, they will be sent via data lines that are secured by encryption 13 to a network of computers 14 transfer. At the computer network 14 it is a plurality of computers that each execute the functions described below in parallel and then validate their results with each other. Especially when the computers of the computer network 14 are assigned to different operators, this can ensure that the computers are not manipulated with regard to the interests of individuals.

In the computer network 14 Hash values for measured value time series are calculated, which can later be used to determine with a high degree of certainty whether an archived measured value series corresponds to the measured value series on which the hash value calculation was based.

Furthermore, in the computer network 14 Evaluation variables for measured value time series determined. The evaluation parameters are selected in such a way that it can be subsequently checked for compliance with the feed-in conditions. In the present example, also for the sake of clarity, only one evaluation variable is calculated, namely the active power rate after clarification of a grid failure resulting in a voltage breakdown. However, it is of course possible and also regularly displayed to calculate a large number of evaluation variables.

Provided that the hash value calculation and the determination of the evaluation variables have been completed and the validation by the individual computers of the computer network 14 The hash values and calculation quantities - but not the measured value series - are passed to a database network 15 transmitted, which works according to the blockchain principle. Similar to the network of computers 14 it is not a singular database, but rather a plurality of databases that synchronize with each other in a network, so that - especially if the individual databases in the network are assigned to different operators - there is a high level of security against manipulation.

When adding the hash value and the associated evaluation parameters, compliance with the feed-in conditions is checked based on the evaluation parameters based on the principle of a smart contract. For this purpose, the feed conditions are in a computer protocol 16 mapped, which can carry out the corresponding check for individual conditions and / or all conditions together on the basis of the evaluation variables.

The calculated hash value, the associated evaluation parameters and the verification of compliance with the feed-in conditions based thereon are stored as a new data record in the database of the database network 15 added.

The database or the newly added data record has the following structure:

Due to the blockchain technology used according to the invention, a later change or manipulation, but also deletion of the data is practically not possible.

On those in the database network 15 stored data can be accessed at any later time by any party, the access can be regulated in a known manner via access rights, so that only authorized persons can actually view the data.

Claims (10)

Method for monitoring compliance with the feed-in conditions of a power grid (1) by one or more power generation units (4, 5) feeding in it, comprising the steps: - Detecting the voltage and current strength per phase at the grid feed-in point of a power generation unit (4, 5) or a group ( 6) of energy generation units (5) for forming measured value time series; - Calculation of hash values for measured value time series; - Determination of evaluation variables from measured value time series; - adding the hash values and evaluation values to a distributed ledger database; - Checking compliance with the feed-in conditions on the basis of the evaluation variables in the distributed ledger database by means of a computer log depicting the feed-in conditions (16). Procedure according to Claim 1 , characterized in that a measurement time series is only formed when a fault signal is present on the part of the power network (1), preferably for the duration of the fault signal being present. Procedure according to Claim 2 , characterized in that the measured value time series is supplemented by measured values which were recorded a predetermined period before and / or after the presence of a fault signal. Method according to one of the preceding claims, characterized in that the result of the check is stored in the distributed ledger database. Method according to one of the preceding claims, characterized in that the hash value calculation for measured value time series and / or determination of evaluation variables for measured value time series are carried out for validation by more than one instance. Method according to one of the preceding claims, characterized in that the evaluation variable comprises the active power rate after clarification of a network failure resulting in a voltage breakdown. Method according to one of the preceding claims, characterized in that the detection of the voltage and current strength per phase at the grid feed-in point is carried out by a calibrated and / or lead-sealed detection module (12). Method according to one of the preceding claims, characterized in that the voltage and current strength per phase are recorded at a sampling rate of at least 1 kHz, preferably at least 2 kHz, further preferably at least 5 kHz. Arrangement (100) comprising at least one energy generation unit (4, 5) which feeds into a power grid (1) at a grid feed point, characterized in that a detection module (12) for detecting the voltage and current per phase is provided at the grid feed point and the components of the Arrangement (1) for executing a method according to one of the preceding claims. Set of computer program products, comprising program parts which, when loaded into a computer or into networked computers, for carrying out the method according to one of the Claims 1 to 9 are designed.

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