Patent Application
20090254224
The invention relates to a Wind turbine comprising at least two communication protocol handlers (PH), said protocol handlers (PH) comprising means for generating and interpreting SCADA related data (SCADA: Supervisory Control And Data Acquisition) according to an associated communication protocol and wherein said at least two protocol handlers (PH) are associated to different communication protocols.
Moreover, it may be possible to design a wind turbine which may fit into virtually most environments.
The strategically distributed nature of wind power presents unique challenges. A wind park comprises several wind turbines located on- or offshore, and often covers large geographic areas.
These factors usually require a variety of networked interconnections and telecommunication technologies for monitoring and controlling wind power electric generating facilities referred to as SCADA (SCADA: Supervisory Control And Data Acquisition).
Wind turbines over different SCADA networks often communicate via different communication protocols and are often proprietary dependent to the manufacturer. This fact makes it very complicated for owners and operators to integrate different types of wind turbines e.g. in a wind park with a central control.
To solve this problem, a new IEC (IEC: International Electro technical Commission) standard “IEC 61400-25” is made that defines all details required to connect wind power plant components in a multi-vendor environment and to exchange the information made available by a component. The standard includes wind power plant specific information, the mechanisms for information exchange, the mapping to communication protocols, and the system configuration. The standard defines or describes a number of communication protocols. To support the standard, a wind turbine must support one of the predefined communication protocols. IEC 61400-25 is developed in order to provide a uniform communications basis for the monitoring and control of wind power plants. It defines wind power plant specific information, the mechanisms for information exchange, the mapping to communication protocols, and the system configuration. In this regard the standard defines all details required to connect wind power plant components in a multi-vendor environment and to exchange all information of the components.
International patent application WO2005/055538 discloses a method and a system for transmitting data via a data bus including a gateway for converting data into data in a format according to a specific standard (IEC 61850). A similar solution has been developed with reference to the IEC 61400-25 standard. A problem related to such use of converters along the communication line between the wind turbines is that the gateway may represent a subject to single point failure. If the gateway breaks down, all wind turbines that are connected to the gateway are out of reach, communication-wise.
Moreover, such conversion may result in loss of information as a conversion into a certain format evidently must include that an output format is restricted to fit the relevant protocol.
The present invention presents a wind turbine supporting at least two of the protocols defined in the IEC 61400-25 by means of several protocol handlers—a multi-protocol wind turbine. This is a very advantageous feature in that the same type of wind turbine may operate with different operators using different communication protocols, e.g. in different wind parks. The SCADA related data may, according to the invention, be any data that is related to monitoring and/or control of wind turbines.
Another very advantageous feature of an embodiment of the present invention is that a multi-protocol wind turbine may be surveyed and/or controlled by different systems of different protocols. For example a utilities company may wish to have direct access to a wind turbine for reasons of surveillance or monitoring of the wind turbine. This is normally only possible if the utilities company has hardware and/or software based system running the same protocol as the wind turbine currently runs. In accordance with the present invention it is possible for the utilities company to contact the wind turbine by means of a system running another protocol than the current protocol of the wind turbine. This is very beneficial in that no special software or hardware needs to be installed at a third party e.g. a utilities company to communicate with a wind turbine of the present invention to obtain monitoring or control.
The protocol handlers may, according to an embodiment of the invention, be devices that comprise a protocol encoder and decoder according to one or several specific communication protocols. Means for generating SCADA related data provides according to the invention means for wrapping data in a predefined way according to the current protocol. Means for interpreting SCADA related data provides in accordance with the present invention means for decoding the data according to the current protocol. Therefore, the term protocol handler may be understood as a protocol driver. The protocol handlers may be located outside or inside the wind turbine.
The term communication protocol is according to the present invention to be understood as a predetermined pattern of wrapping, encoding or decoding data to be transmitted via a data communication network.
In another advantageous embodiment of the invention, it is possible to utilize two different communication protocols simultaneously and hence obtain different communication priorities of the data. This way it is possible that e.g. critical data such as power control instruction data are transmitted faster to the wind turbine than non critical data such as a statistical temperature reading.
It should be noted that the at least two protocol handlers which both comprise means for generating and interpreting data evidently further may be comprised in one single unit e.g. a processor.
Another advantageous feature of having at least one protocol handler placed in relation to the operation of a wind turbine is that it eliminates the need for converting data transmitted to the wind turbine according to one protocol to a another specific protocol applied by the wind turbine. Because it is possible to transmit data to a wind turbine without converting, the transmission time from a central server to the wind turbine may be minimized or reduced. The minimization of transmission time may be very advantageous, in situations where e.g. a precise fault detection or power control is needed.
Another advantageous feature of having at least two protocol handler placed in a wind turbine in a wind power plant is that it gives freedom to easily integrate further substations or wind turbines in a wind power plant. As such further substations or wind turbines may be manufactured by different manufactures and therefore supporting different data protocols.
Examples of further substation integrated into the wind power plant may e.g. be distributed databases for storing measured data, further metrological stations or even further wind turbines from different manufactures.
In an embodiment of the invention, each of said at least two protocol handlers comprise means for receipt and transmission of one communication protocol.
In an embodiment of the invention, said at least two protocol handlers are comprised in a single expanded protocol handler comprising means for generating and interpreting SCADA related data.
According to an embodiment of the invention an expanded protocol handler may comprise means for handling several protocols. This may be done in different ways. An expanded protocol handler handles packets of different protocols and need thereby of necessity to know a packet defined in one protocol from another defined in another protocol. This functionality may be obtained by means of the expanded protocol handler detecting the protocol of relevant data packet by extracting protocol specific data from said relevant data packet and processing said relevant data packet according to said protocol specific data. Another way of obtaining this functionality according to an embodiment of the invention may be by means of at least two protocol handlers being merged in said expanded protocol handler comprising means for handling data of at least two different protocols within the expanded protocol handler, without determination of protocol type. The expanded protocol handler may in this way comprise means for interpreting and generating data packets of several protocols.
In an embodiment of the invention, said protocol handlers are comprised by a SCADA interface.
In accordance with the present invention, a SCADA interface may be any physical or software-based gateway or port that receives data e.g. via a cable. The SCADA interface may be physically or wirelessly linked with a SCADA server or a control station of a wind park.
In an embodiment of the invention, one of said different communication protocols is based on SOAP-based (Simple Object Access Protocol) web services. It should be noted that the SOAP-based web services also may be referred as XML web serviced.
In an embodiment of the invention, one of said at least two different communication protocols is the MMS protocol.
In an embodiment of the invention, the protocol handler simply converts the SCADA related data from the current protocol into an internal protocol or language of the wind turbine.
It is within the scope of the present invention that all protocol handlers may be assembled into one single expanded protocol handler PH.
One advantageous way of implementing this invention may be by applying a switch or configuration setting for switching between different protocols at the SCADA interface of a wind turbine. Hereby it is possible for e.g. a wind park operator during installation and calibration of a wind turbine to switch to the protocol of the current wind park. This is very advantageous in that the same type of wind turbine may be applied to different wind parks using different communication protocols and function without the need for any gateway. Furthermore, the wind park operator may change communication protocols of the wind park and still use the same wind turbines.
One very advantageous feature of implementing this invention in individual wind turbines in a wind power plant is that it gives the park administrator the opportunity to communicate directly to such individual wind turbine.
Another very advantageous feature of implementing this invention in each individual wind turbine in a wind power plant is that it eliminates the need of a protocol converter used as gateway to the wind power plant. The need of converting data from one protocol sent by e.g. a control station to another protocol supported by the wind turbines in the wind power plant may be subject to a single point failure. If the converter breaks down it is not possible to communicate to any of the wind turbines in the power plant.
In an embodiment of the invention, said at least two different SCADA protocols are comprised defined in the IEC 61400-25 standard.
In an embodiment of the invention, at least one of said protocol handlers is distributed in the wind turbine. This means that some functionality of the protocol handlers is distributed in different places of the wind turbine. There may e.g. be an embedded processor located in the tower performing the protocol interpretation.
Furthermore, the invention relates to a wind turbine comprising at least one SCADA interface (SI) to at least one external SCADA server (SCS),
Said SCADA interface (SI) communicating SCADA related data (SRD) and said SCADA interface comprises a multi-protocol SCADA interface enabling encoding and decoding of SCADA related data (SRD) according to at least two different SCADA protocols.
The present invention presents a wind turbine related to a SCADA interface supporting at least two of the protocols defined in the IEC 61400-25. This is a very advantageous feature in that the same type of wind turbine may operate with different operators using different communication protocols, e.g. in different wind parks. The SCADA related data may, according to the invention, be any data that is related to monitoring and/or control of wind turbines.
The SCADA server may, according to an embodiment of the present invention, be any server related to one or several wind turbines which is used for operating set points, sending commands, monitoring the system, storing historical data or may furthermore send power control instructions to the wind turbine. The SCADA server may be a server connected to at least one wind turbine or one or several of the wind turbines in a wind park.
In an embodiment of the invention, said SCADA server (SCS) is related to a wind park control station.
In an embodiment of the invention, said SCADA interface is located inside the wind turbine.
According to the invention a SCADA server may be related to a wind park control station which may be a central unit performing monitoring and control of the wind park.
A wind turbine according to the present invention may operate without any adaptation in any wind park matching the IEC 61400-25 standard. This is very advantageous due to the fact that the same type of wind turbine may be utilized in different wind parks. Moreover, it is possible for a wind park operator or owner to add one or more multi-protocol wind turbines according to the invention in a wind park comprising wind turbines from other vendors.
Furthermore, the invention relates to a multi protocol SCADA interface related to a wind turbine comprising
In an embodiment of the invention, said at least two different protocols are part of the IEC 61400-25 standard.
In an embodiment of the invention, one of said at least two different communication protocols is defined by SOAP-based web services.
In an embodiment of the invention, one of said at least two different communication protocols is the MMS protocol.
In an embodiment of the invention, one of said at least two different communication protocols is the DNP3.
In an embodiment of the invention, one of said at least two different communication protocols is the IEC 60870-5-104 protocol.
In an embodiment of the invention, one of said at least two different communication protocols is the OPC-XML-DA protocol.
In an embodiment of the invention, one of said at least two different communication protocols is the GOOSE protocol.
In accordance with the present invention it is possible to support or understand at least two different data communication protocols.
Moreover, the invention relates to a method of generating and interpreting SCADA related data in a wind turbine according to at least two different SCADA related communication protocols comprising the steps of
In an embodiment of the invention, said method further comprising the step of generating a response according to said protocol type
In an embodiment of the invention, an expanded protocol handler detects the protocol type of a received data packet by extracting protocol defining data from said received data packet and processes said received data packet according to said protocol specific data.
In an embodiment of the invention, said protocol handler are comprised by a SCADA interface.
A protocol handler may, according to an embodiment of the invention, be devices that comprise a protocol encoder and decoder according to one or several specific communication protocols. Means for generating SCADA related data provides according to the invention means for wrapping data in a predefined way according to the current protocol. Means for interpreting SCADA related data provides in accordance with the present invention means for decoding the data according to the current protocol. Therefore, the term protocol handler may be understood as a protocol driver. The protocol handlers may be located outside or inside the wind turbine.
It is very advantageous feature in that the same type of wind turbine may operate with different operators using different communication protocols, e.g. in different wind parks. A protocol handler related to a wind turbine handles incoming data packets according to a protocol type. The handling of a data packet may according to an embodiment of the invention be understood as an interpretation of the data packet and an ensuring of that the data packet is processed correctly. Furthermore, the protocol handler comprises means for generating a response, i.e. establishment of data packets defined in the same communication protocol type. Evidently, the protocol handler may generate data packets of different protocols automatically.
Another very advantageous feature of an embodiment of the present invention is that a multi-protocol wind turbine may be surveyed and/or controlled by different systems of different protocols.
It should be noted that the at least two protocol handlers which both comprise means for generating and interpreting data evidently further may be comprised in one single unit e.g. a processor.
Moreover, the invention relates to a method of generating and interpreting SCADA related data in a wind turbine according to at least two different SCADA related communication protocols comprising the steps of
In an embodiment of the invention, said method further comprising the step of generating a response according to said protocol type.
Moreover, the invention relates to use of at least two different SCADA related communication protocols in a wind turbine.
The invention will be described in the following with reference to the figures in which
a illustrates an example of a SCADA interface according to an embodiment of the invention,
b illustrates another example of a SCADA interface according to an embodiment of the invention,
A low speed shaft extends out of the nacelle front and is connected with a wind turbine rotor through a wind turbine hub 4. The wind turbine rotor comprises at least one rotor blade e.g. three rotor blades 5 as illustrated.
Nacelles 3 exists in a multitude of variations and configurations but in most cases the drive train 14 in the nacelle 3 almost always comprises one or more of the following components: a gear 6, a coupling (not shown), some sort of breaking system 7 and a generator 8. A nacelle 3 of a modern wind turbine 1 can also include a converter 9, an inverter (not shown) and additional peripheral equipment such as further power handling equipment, control systems, hydraulic systems, cooling systems and more.
The weight of the entire nacelle 3 including the nacelle components 6, 7, 8, 9 is carried by a load carrying structure 10. The components 6, 7, 8, 9 are usually placed on and/or connected to this common load carrying structure 10. In this simplified embodiment the load carrying structure 10 only extends along the bottom of the nacelle 3 e.g. in form of a bed frame to which some or all the components 6, 7, 8, 9 are connected.
A typical wind turbine may further comprise a number of sensors or meters, e.g. vibration sensor 21, gear oil thermometer 22 and generator thermometer 23. It is noted that many other sensors and meters for measuring conditions of wind turbines are comprised in a typical wind turbine.
The wind turbine controller WTC may be located inside or outside the wind turbine WT.
The figure illustrates that a device driver handles incoming data packets P1DP, P2DP, . . . , PnDP, typically comprising SCADA related data, on a SCADA interface SI. These data packets P1DP, P2DP, . . . , PnDP are according to the invention defined by different protocols. The data packets P1DP, P2DP, . . . PnDP may comprise e.g. requests or responses. Thus, the present figure illustrates that the SCADA interface SI supports several protocols, which in this figure is illustrated by a protocol 1 datapacket P1DP, a protocol 2 datapacket P2DP and a protocol n datapacket PnDP. The SCADA interface SI may transmit the incoming data packets to a control mechanism of the wind turbine, e.g. a wind turbine controller WTC, where after the instructions are to be executed in the wind turbine WT. This execution may e.g. comprise setting a value, influence on an actuator or reading a value of a meter in the wind turbine.
The wind turbine controller WTC is to be understood as the main control unit of a wind turbine. It may be located inside or outside the wind turbine.
The SCADA interface SI may in alternative embodiments of the invention be located outside the wind turbine controller or outside the wind turbine.
The decoding and encoding of data packets of different protocols may according to an embodiment of the invention be done with a subsequent translation of data packets into an internal wind turbine protocol.
The SCADA server SCS may be comprised in a control station CS and may be located local or remote to the wind turbine controller WTC. The SCADA server may be separated by a data communication network DCN or a public data communication network PDCN. The SCADA server is in an embodiment of the invention to be understood as any computer connected to the wind turbine communicating monitoring and/or control data, e.g. a PC (PC: Personal Computer) for surveillance of a wind turbine located at a utilities company.
The IEC 61400-25 presents a uniform information exchange system to eliminate problems of many different proprietary communication systems to which intercommunication is difficult or impossible. Thus, the IEC standard contributes homogeneity of the different types of SCADA systems.
The wind power plant specific information describes the crucial and common process data, meta-data (data about data, e. g. scale factor or engineering unit), and configuration data of a wind power plant. Process information is hierarchically structured and covers for example common process information found in the rotor, generator, converter, grid connection etc. The data may be simple (value, timestamp, and quality) or more comprehensive (adding more meta-data, for example engineering unit, scale, description, short hand reference, statistical and historical information of the process value). All information of a wind power plant defined in IEC 61400-25 is name tagged—it defines a comprehensive name space. A concise meaning of each signal is given. The standardized wind power plant information can be easily extended by means of a name space extension rule. All process and meta-data can be exchanged by corresponding services. Access to the metadata (including configuration information with regard to the wind power plant information model and services and communication stacks) provides the so-called self-description of a device.
The IEC 61400-25 allows SCADA systems to communicate with wind turbine controllers from multiple vendors. The standardized self-description (contained either in an XML file or retrieved online from a device) can be used to configure SCADA applications. Standardization of SCADA applications are excluded in IEC 61400-25 but standardized common wind turbine information provides means for re-use of applications and operator screens for wind turbines from different vendors.
From a utility perspective unified definitions of common data minimize conversion and re-calculation of data values for evaluation and comparison of all their wind power plants.
The present invention presents a wind turbine related to a SCADA interface supporting at least two of the protocols defined in the IEC 61400-25. This is a very advantageous feature in that the same type of wind turbine may operate with different operators using different communication protocols, e.g. in different wind parks.
a illustrates an example of a SCADA interface SI which in an embodiment of the invention supports input and output from five different protocols handled by different protocol handlers PH.
Protocol 1 handler PH1 refers to means for interpreting web services which could be a software component that is described via WSDL(WSDL: Web service description language) and is capable of being accessed via standard network protocols such as, but not limited to, SOAP (SOAP: Simple Object Access Protocol) over HTTP (HTTP: hypertext transfer protocol). Thus, a web service is, according to the invention, a hosted application controlled through SOAP requests which returns results as SOAP responses.
Protocol 2 handler PH2 refers to means for interpreting the MMS (MMS: Manufacturing Message Specification) protocol. MMS is an ISO 9506 standard. Control Networks uses the MMS protocol and a reduced OSI stack with the TCP/IP protocol in the transport/network layer, and Ethernet and/or RS-232 as physical media. This means that all communication handling will be the same, regardless of network type and connected devices. The protocol defines communication messages transferred between controllers as well as between the engineering station and the controller (e.g. downloading an application or reading/writing variables).
Protocol 3 handler P3H refers to means for interpreting the DNP3 (DNP3: Distributed Network Protocol version 3). Data transmitted over DNP3 is typically process information required for operational purposes. DNP3 is a non-proprietary, standards-based communications protocol designed for maximum compatibility across a variety of networks.
Protocol 4 handler P4H refers to means for interpreting the IEC 60870-5-104 protocol which is a SCADA protocol specifically intended for electric power applications. It reports changes in the state of the monitored data points and can report time-stamps for these changes. It includes some power-system specific data types for monitoring some particular power devices (e.g. transformer tap positions) and has specific control types to ensure that only the correct output is changed when a command is issued. The protocol includes a concept of a current state for most data points but generally only reports the changes to those points.
Protocol 5 handler P5H refers to means for interpreting the OPC XML-DA (OLE (Object Linking and Embedding) for Process Control Data Access) protocol which based on XML and is used to provide both the data dissemination and control capabilities for the distributed data acquisition system.
The figure illustrates that different protocol handlers (P1H, P2H, P3H, P4H) may be comprised in a SCADA interface of a wind turbine. The Protocol handlers may, according to an embodiment of the invention, be devices that comprise both a protocol encoder and a protocol decoder according to their respective protocols. The encoder handles the wrapping of data in a predefined way according to the current protocol. The decoder handles the decoding of the data which means unwrapping of incoming data according to the current protocol. Therefore, the term protocol handler may be understood as a protocol driver. It should be noted that the protocol handlers (P1H, P2H, P3H, P4H) may be located anywhere in relation to a wind turbine.
The figure moreover illustrates that the SCADA interface communicates with control means CM for the wind turbine. This may e.g. be a wind turbine controller WTC or other means for controlling a wind turbine or elements of a wind turbine.
The five different protocols illustrated in this figure is not to be understood as limiting, merely as an example of five different protocols applicable within the scope of the present invention.
b illustrates another example of a SCADA interface SI which in an embodiment of the invention supports input and output from six different protocols. This figure has the same elements as
Protocol 6 handler P6H refers to means for interpreting the GOOSE (Generic Object-Oriented Substation Event) protocol, which is a protocol providing high-speed communication of wind turbine status changes over a substation local area network.
The six different protocols illustrated in this figure are not to be understood as limiting, but merely as an example of six different protocols applicable within the scope of the present invention.
The term wind turbine system WTS may designate a wind turbine WT, a substation, combinations thereof or a wind power plant. The protocol handler PH or the expanded protocol handler EPH may in an embodiment of the invention be positioned in the housing of the wind turbine WT. According to an alternative embodiment of the invention the protocol handler may be distributed and executed on separate data processing circuitry as long as the protocol handler is associated to and functioning in relation to the wind turbine WT in question.
| Number | Date | Country | Kind |
|---|---|---|---|
| PA 2006 01631 | Dec 2006 | DK | national |
The present application is a continuation of pending International patent application PCT/DK2007/000538 filed on Dec. 10, 2007 which designates the United States and claims priority from Danish patent application PA 2006 01631 filed on Dec. 12, 2006, the content of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/DK2007/000538 | Dec 2007 | US |
| Child | 12483938 | US |
