Pitch drive controller of a wind turbine, pitch drive control unit and method for controlling a pitch drive controller

Description

[0001] This document describes a pitch drive controller for a wind turbine with multiple rotor blades fixed to a rotor hub. The controller uses an electric motor to adjust the rotation of the rotor blades at the hub. For each rotor blade, the pitch drive controller has at least one pitch drive control unit to control at least one pitch drive motor. Thus, for the electric rotation adjustment of each rotor blade, one or more pitch drive control units are used, with each individual pitch drive control unit controlling one or more pitch drive motors. It is also possible for individual pitch drive motors to be controlled, or to be controlled, by more than one pitch drive control unit.The control of a pitch drive motor by more than one pitch drive control unit can be achieved in such a way that the pitch drive motor is controlled simultaneously by more than one pitch drive control unit, or in such a way that it is controlled at any given time only by one pitch drive control unit, but the control can be switched from one pitch drive control unit to another.

[0002] Each pitch drive control unit has control electronics for the pitch drive motor and a control output to the pitch drive motor, whereby the pitch drive motor is supplied with the electrical power required for its operation from the control electronics via the control output. Furthermore, it may be possible to exchange sensor signals between the pitch drive control unit and the pitch drive motor via the control output or a separate signal interface.

[0003] Furthermore, each pitch drive control unit contains a computing unit with at least one processor set up for operating the pitch drive control unit.

[0004] A system according to the preamble of claims 1 and 5 is described in NZ 556 642 A.

[0005] CN 101624 969 A discloses a system with multiple servo control units for controlling pitch motors, where one servo control unit can control two pitch motors for redundancy. US 2009 / 0169378 A1 discloses a pitch control system in which individual pitch drives for one rotor blade can have inputs for sensors of other rotor blades. EP 1 763 126 A1 describes a pitch controller in which the individual pitch drive controllers communicate with a higher-level central control unit of a wind turbine via a bus system.

[0006] At least one pitch control unit of the pitch drive controller according to the invention also has an external communication interface to a central control unit of the wind turbine. This enables the pitch control units connected in a group to communicate with the central control unit, at least via the at least one pitch control unit with the external interface. In a preferred embodiment according to the invention, several or all pitch control units of the pitch drive controller can also have such an external communication interface. This increases redundancy.

[0007] Furthermore, each individual pitch drive control unit can have one or more than one application module, which has one or more than one processor for operating the drive control unit, and / or one or more than one additional interface for optical or electrical signals.

[0008] A pitch drive control unit and a method for controlling a pitch drive controller are also described.

[0009] The control electronics of each pitch control unit often include an inverter that controls the pitch drive motor. Therefore, "pitch control units" are also referred to as "pitch inverters." In the following text, these two terms are used synonymously. Thus, for the purposes of this text, "pitch inverter" is always understood to mean a "pitch control unit" more generally, regardless of whether the electronics of the "pitch control unit" actually include an inverter for converting alternating current to direct current. The subject matter of the invention is independent of the specific electrical implementation of the control of the pitch drive motor by the pitch drive control unit.

[0010] Typically, such pitch inverters (or more generally, pitch controllers) are connected to a central control unit via a fieldbus. This central unit sends setpoints to the inverters and receives measured values. There is no direct communication link between the pitch inverters themselves. Therefore, all communication between the pitch inverters must take place via the central control unit. This is complex and time-consuming. Furthermore, disturbances in the relatively long communication path or in the central control unit can result in certain information being lost in the pitch inverters.

[0011] The object of the present invention is therefore to improve the communication between the pitch drive control units of the individual rotor blades of a rotor hub.

[0012] This problem is solved by a pitch drive controller for a wind turbine with the features of claim 1, a pitch drive control unit with the features of claim 5, and a method for controlling a pitch drive controller with the features of claim 14. Advantageous embodiments are found in the dependent claims.

[0013] In a pitch drive controller of the type mentioned above, each pitch drive control unit has a local communication port and is connected to the other pitch drive control units of the wind turbine via this local communication port. Specifically, all pitch drive control units connected via this cross-communication are located in the same rotor hub of the wind turbine. This configuration ensures short communication paths for all pitch drive control units of the pitch drive controller. Each pitch drive control unit can therefore communicate with the other pitch drive control units and exchange data via its communication port and the communication channel radiating from it, without requiring communication with the central control unit of the wind turbine.

[0014] In one embodiment of the invention, this cross-communication can be implemented as a fieldbus communication system. The fieldbus provides robust, reliable communication for industrial environments and enables the connection of multiple pitch drive control units in a closed data bus cabling system. Expansions or redundancies of the cabling can be easily achieved within a data bus cabling system.

[0015] In another embodiment of the invention, cross-communication can be implemented as point-to-point communication. This is advantageously achieved through direct cabling between two communication partners. This allows the use of simple and robust communication protocols.

[0016] In a further embodiment according to the invention, cross-communication can take place via one or more network nodes, which also enable simple and robust communication protocols.

[0017] According to the invention, the pitch drive control units of the pitch drive controller can be configured to exchange one or more of the following types of data: Setpoint values, in particular those for the rotor blade position control; Actual values, in particular those for the rotor blade position control; Measured values ​​received and / or acquired from sensors connected to the pitch drive control unit; Calculated values, in particular from the received and / or acquired measured values; Operating parameters of the pitch drive control unit, including the software version of application software and / or firmware or an installable data processing program with the application software and / or the firmware or software updates; Absolute or relative time information; Data packets from safety modules of the pitch drive control units themselves, the pitch drive controller and / or the central control unit of the wind turbine

[0018] The exchange of data values ​​can take place, in particular, within the framework of the methods or process steps described in more detail below. For this purpose, the processing unit of the pitch control devices is configured to carry out the respective process steps, possibly in conjunction with the processing unit of at least one further pitch control device, wherein the cooperating pitch control devices are interconnected via the cross-communication according to the invention.

[0019] According to a preferred embodiment of the proposed pitch drive controller, the pitch drive controller includes at least one pitch drive control unit with an external communication interface to a central control system of the wind turbine. This makes it possible to operate communication to a central control system (central communication) and the proposed cross-communication (local communication) in parallel. Thus, the pitch drive controller and / or the pitch drive control units according to the invention, with the (additional) cross-communication, can also be operated in conventional wind turbines with central control systems. The control is fundamentally centralized, and the cross-communication allows for the supplementary implementation of, for example, further control and safety features, as described in this text. This leads to significantly improved and safer operation of the wind turbines.In a preferred embodiment of this parallel central and cross-communication (local communication), at least one pitch drive control unit for each pitch drive (particularly in the sense of a pitch drive motor) may have both a local communication port and an external communication port. According to the invention, the local and central communication can be technically implemented via a common (i.e., the same) communication, e.g., a fieldbus communication with, for example, the respective local and central communication addresses. However, according to the invention, it is also possible to use technically different communication methods and thus separate and preferably independently operating communication systems. This increases redundancy, e.g.,by the cross-communication proposed according to the invention autonomously taking over a safety control in the event of a failure of the central communication.

[0020] If not every pitch drive control unit—or at least not one of potentially several pitch drive control units for a pitch drive motor used to adjust a rotor blade—has an external communication port for communication with the central controller, the processing unit of a pitch drive control unit equipped with an external communication port can be configured to act as a gateway and mediate communication between the central controller and the pitch drive control units equipped only with local cross-communication. This function can also be used if an external communication port of a pitch drive control unit fails, by routing communication to the central controller via another pitch drive control unit acting as a gateway.

[0021] The invention further relates to a pitch drive control unit for controlling a pitch drive motor, wherein the pitch drive control unit comprises control electronics, a control output to the pitch drive motor, a computing unit with a processor configured for operating the pitch drive control unit, and an external communication interface to a central control system of the wind turbine. According to the invention, the pitch drive control unit has a local communication interface and can be connected via this local communication interface to the other pitch drive control units of the wind turbine in a cross-communication arrangement. Several of these pitch drive control units connected via the cross-communication then form the pitch drive controller of the wind turbine. In conventional wind turbines with three rotor blades, at least three pitch drive control units are typically provided.

[0022] According to the invention, cross-communication is specifically designed to occur only with other pitch drive control units of the wind turbine, and in particular only with pitch drive control units located in the same rotor hub of the wind turbine. This can be achieved, for example, by limiting the cable lengths used and / or usable for cross-communication, e.g., within the framework of fieldbus communication or a point-to-point connection. Accordingly, the invention relates to the use of such a pitch drive control unit in cross-communication between pitch drive control units in the same rotor hub of a wind turbine.

[0023] According to the invention, the local communication connection can comprise a wired electrical and / or optical interface. Wireless communication using standard wireless communication interfaces is also conceivable. However, in the environment of a wind turbine, wired communication generally proves to be more robust and reliable. The communication connection can preferably be configured to establish a fieldbus data connection or a proprietary data connection. Optical communication is particularly robust against electromagnetic interference; however, a wired electrical data connection can also generally enable reliable communication, if necessary with appropriate shielding of the data line.

[0024] In one embodiment according to the invention, the pitch drive control unit can have integrated and / or connectable sensors for acquiring measured values ​​(at least one sensor). The processing unit of the pitch drive control unit is then configured to process the acquired measured values. The processing of the measured values ​​can include evaluating the measured values ​​and / or transmitting the measured values ​​to the central server. This enables a pitch drive control unit to monitor the state of hardware components and / or states of the wind turbine by monitoring measured variables and / or calculated variables (calculated values), for example, by means of threshold detection, checking against a valid value range, long-term evaluation of an average value, fast Fourier transforms ( Fast Fourier Transform (FFT)) for the decomposition of a digital signal into its frequency components and their analysis, calculation of frequency distributions (histogram), adaptation of a characteristic curve or map, use as training data for an artificial neural network or the like.

[0025] In a further embodiment of the invention, at least one sensor in the pitch drive control unit can be checked by comparing its measured value with the measured value of at least one corresponding sensor in at least one other pitch drive control unit, preferably in the same wind turbine or in adjacent wind turbines. It is assumed that the measured quantity is identical or at least within a tolerance in the measurements taken in the pitch drive control units under consideration. The measured quantity considered for this purpose can, for example, be the frequency of the voltage of the electrical supply network, but its voltage can also be suitable for this purpose.Within a wind turbine, temperature measurement can also be used for this purpose, for example by using a temperature sensor outside the pitch drive control unit, in particular a temperature sensor located on an emergency power supply. Specifically, the processing unit of a pitch drive control unit (or several or all of the pitch drive control units in one wind turbine or in several wind turbines) can be configured to perform sensor verification, with the sensor being either integrated into the pitch drive control unit or connected to a sensor port of the pitch drive control unit.

[0026] In a further embodiment of the invention, signal conversion from more than one sensor of the pitch drive control unit can be performed by a single analog-to-digital converter (ADC) of the pitch drive control unit. According to the invention, this ADC can be verified by comparing a measured value converted analog-to-digitally by it with the measured value of at least one corresponding sensor in at least one other pitch drive control unit (e.g., in the same wind turbine or in neighboring wind turbines, i.e., with similar environmental and / or operating conditions). It is assumed that the measured quantity is identical or at least within a tolerance in the measurements taken in the pitch drive control units under consideration.The measured quantity considered for this purpose can be, for example, the frequency of the voltage of the electrical supply network, but its voltage can also be suitable. Within a wind turbine, a temperature measurement can also be used for this purpose, for example, by using a temperature sensor outside the pitch drive control unit, in particular a temperature sensor located on an emergency power supply. Specifically, the processing unit of a pitch drive control unit (or several or all of the pitch drive control units, for example, in one or more wind turbines) can be configured accordingly to perform the check.

[0027] In a further embodiment according to the invention, the pitch drive control unit can include a safety module in which safety functions are implemented that can be executed based on data acquired and processed in the safety module. Preferably, according to the invention, the acquired data also includes data received from at least one pitch drive control unit via cross-communication, wherein the processing unit of the pitch drive control unit is configured to also evaluate this data in the safety module. In this way, redundancy can be achieved via the network of pitch drive control units through cross-communication, without requiring such redundancy to be achieved in a single pitch drive control unit alone. This leads to cost advantages with increased safety, particularly when – as is common in wind turbines – at least three rotor blades, each with its own pitch drive control unit, are provided.This inevitably leads to double redundancy without the need for additional components in the single pitch drive control unit.

[0028] A significant advantage arises when, according to one possible embodiment of the invention, the computing unit of the pitch drive control unit is configured to send measured values ​​and / or setpoints for the rotational adjustment of the rotor blade to other pitch drive control units connected via cross-communication and / or to receive them from other pitch drive control units. Based on the received measured values ​​and / or setpoints, the computing unit can then intervene locally in the pitch drive control. Here, the local cross-communication in the rotor hub of the wind turbine enables particularly fast communication with a significantly reduced latency compared to communication with the central control unit of the wind turbine. This considerably improves the dynamics of the pitch drive control.

[0029] Furthermore, the processing unit of the pitch drive control unit can be configured to receive measured values ​​and / or setpoints and / or calculated values ​​from other pitch drive control units and to compare measured values ​​acquired within the pitch drive control unit itself against an expected value derived from the measured values ​​and / or setpoints and / or calculated values ​​received from the other pitch drive control units. This improves monitoring and diagnostics because these can be performed with current data and locally within the pitch drive control unit.

[0030] In a further preferred embodiment of the invention, the pitch drive control unit can have an input interface with a user input device and at least one display device. The user input device can include buttons for user input. The display device can be a display or simply one or more light indicators, e.g., LEDs. Thus, parameterization and adjustment of the pitch drive control unit, for example during commissioning, can be easily carried out at the installation site, i.e., typically in the rotor hub of the wind turbine. Space is usually very limited there, which makes the use of commissioning and service equipment such as laptops difficult. The input interface (Human Machine Interface, HMI) often eliminates the need for additional equipment during service or commissioning.

[0031] According to the invention, a further simplification of the communication process can be achieved through the proposed cross-communication, whereby the computing unit of the pitch drive control unit, according to one embodiment, is configured to transfer setting parameters of the pitch drive control unit and / or an installable image of the software via cross-communication to another of the pitch drive control units and to store them in the other pitch drive control unit. The setting parameters can, in particular, be entered or predefined in the software for controlling the pitch drive control unit. By entering these setting parameters, the pitch drive control unit can be configured for the specific wind turbine during commissioning. The installable image of the software can, for example, be...This could be an installation file for setting up the application software on the computing unit of the pitch drive control unit (including updates for this) and / or a software image of the pitch drive control unit. In this embodiment of the invention, this provides a complete backup of the pitch drive control unit (also) locally in the other pitch drive control units of the wind turbine that can be addressed via cross-communication, and which can also be accessed via cross-communication.

[0032] In a further development of this embodiment of the invention, the processing unit of the pitch drive control unit can be configured to retrieve the (previously stored) setting parameters of the pitch drive control unit and / or the installable image of the software from one of the other pitch drive control units via cross-communication when one of the pitch drive control units of the wind turbine is replaced, and to configure them in the processing unit of the replaced pitch drive control unit. This can be done through user interaction via the input interface and / or by an automated query of the pitch drive control units accessible via cross-communication. By installing such a software image and / or all adjustable parameters (e.g., setting parameters that can be entered or specified via the software), the replacement unit can be parameterized in the same way as the replaced unit.This facilitates service operations at the wind turbine.

[0033] In this text, the previously described replacement of one of the pitch drive control units encompasses not only the replacement of the complete unit but also the replacement of an application module of a pitch drive control unit that is affected by and uses the software and / or parameter settings. For example, the control software may be implemented on the application module. Even when replacing an application module of the pitch drive control unit, the newly installed application module can be parameterized via cross-communication from another pitch drive control unit or receive software that is installed on the newly installed application module. This is also what is meant by the phrase "replacement of one of the pitch drive control units."

[0034] The invention also relates to a method for controlling the pitch drive controller of a wind turbine already described, comprising at least two, preferably three, pitch drive control units, which are arranged, in particular, in a rotor hub of the wind turbine and can have the aforementioned configuration. According to the invention, the processing units of the pitch drive control units are configured to communicate with each other and exchange and / or store data via cross-communication (preferably within the rotor hub), and specifically not via a central control unit of the wind turbine (which is usually located outside the rotor hub). The method can, in particular, execute the previously described process steps individually, together, or in any combination.

[0035] Accordingly, the computing units of the pitch drive control units can be configured in particular to perform one or more of the following process steps: Transferring and storing the setting parameters of one of the pitch drive control units and / or an installable image of the software of this one of the pitch drive control units to another of the pitch drive control units via cross-communication; reading and installing the setting parameters and / or the installed installable image of the software stored in one of the pitch drive control units in another of the pitch drive control units via cross-communication; receiving measured values ​​and / or setpoints and / or calculated values ​​from other pitch drive control units via cross-communication and checking a measured value and / or calculated value recorded in the pitch drive control unit itself against an expected value that is determined from measured values ​​and / or setpoints and / or calculated values ​​received from the other pitch drive control units;Sending measured values ​​and / or setpoints and / or calculated values ​​for rotor blade pitch control to other pitch drive control units connected via cross-communication; receiving measured values ​​and / or setpoints and / or calculated values ​​for rotor blade pitch control from the other pitch drive control units via cross-communication and locally intervening in the pitch drive control based on the received measured values ​​and / or setpoints and / or calculated values; receiving data from at least one pitch drive control unit via cross-communication and evaluating this data in the safety module to implement safety functions.

[0036] According to the invention, these and other methods or process steps or parts thereof based on the cross-communication proposed according to the invention, as described in this text, can be implemented to increase the dynamics of the control, maintenance and safety of wind turbines.

[0037] Further advantages, features, and applications of the invention will also become apparent from the following description of exemplary embodiments and the drawings. All features described and / or illustrated together, or in any combination that is technically sensible, belong to the subject matter of the invention, even independently of their compilation in the described or illustrated exemplary embodiments or in the claims.

[0038] The only Figure 1Figure 1 schematically shows a pitch drive controller 1 with three pitch drive control units 10, 20, 30 configured as inverters, arranged in a rotor hub of a wind turbine (not shown). In addition to a communication link (not shown) to a central control unit of the wind turbine, the inverters 10, 20, 30 (hereinafter also used synonymously for pitch drive control unit) are interconnected via a cross-communication link 2, which is implemented locally and connects the inverters 10, 20, 30 directly to each other as indicated by the arrows.

[0039] Each of the inverters 10, 20, 30 has a processing unit (not shown) which is configured in a standard manner for controlling the inverters 10, 20, 30. Furthermore, the processing unit is configured for cross-communication 2, enabling the inverters to exchange data directly with each other as described.

[0040] In order to be able to address and input data to the inverters 10, 20, 30 locally without a separate installation device, each of the inverters 10, 20, 30 has a local input interface 11, 21, 31 for user input and user information (Human Machine Interface HMI).

[0041] Without being limited to the procedures and process steps described below, the following functions in particular can be implemented for execution in the computing units, which can be used very effectively especially in the context of wind turbines.

[0042] Cross-communication can be used effectively in a service case involving the replacement of one of the inverters, as explained below, whereby all of the implemented procedure steps can be implemented together, or any selection of the following procedures or functions can be implemented.

[0043] Via cross-communication 2 between inverters 10, 20, and 30, a copy of the (parameter) settings and preferably also the software of one of inverters 10, 20, or 30 is transferred to the other two inverters 20, 30 or 10, 30 or 10, 20 and stored there. If one of inverters 10, 20, or 30 needs to be replaced due to, for example, a hardware defect, this can be identified by the remaining inverters 20, 30 or 10, 30 or 10, 20 via, for example, a different serial number. Through a simple interaction (e.g. a key press) with the user (especially via the corresponding input interface 11 or 21 or 31) a process (procedure) is initiated, according to which the settings and preferably also the software from the images stored in at least one of the remaining two inverters 20, 30 or 10, 30 or 10, 20 are uploaded to the newly installed inverter 10 or 20 or 30 via cross-communication 2.A successful upload can be clearly indicated, for example, by an LED on input interface 11, 21, or 31. The process of detecting and uploading an image can also be triggered automatically without user intervention, for example, after the detection of a new inverter 10, 20, or 30 by identifying a new serial number in cross-communication with the other two inverters 20, 30 or 10, 30 or 10, 20.

[0044] After successful installation, the new inverter (10, 20, or 30) received exactly the same software and parameter data as the replaced unit. It behaves identically.

[0045] A common, state-of-the-art procedure for replacing an inverter involves either manually pre-configuring the inverter with a laptop before transporting it to the rotor hub of the wind turbine, or performing the configuration on-site in the rotor hub using a laptop as a commissioning device. This results in increased logistical effort, and it is essential to know precisely which inverter in the hub is defective before any service call. Furthermore, a potential problem arises: if the old inverter is defective, its parameters may no longer be readable. This necessitates a complete reconfiguration, assuming the configuration parameters are stored and maintained separately.

[0046] The proposed method allows a defective inverter (10, 20, or 30) to be replaced and configured in the rotor hub without complex or additional equipment (such as a laptop for commissioning). This is particularly advantageous due to the limited space available in the rotor hub.

[0047] Furthermore, after performing the proposed procedure, the new inverter 20, 30, 10, 30, or 10, 20 receives an exact copy of the settings and preferably also the software of the defective inverter 10, 20, or 30, so that after the replacement it behaves exactly like the previous one. This process is significantly more reliable against errors than the exchange methods used in the prior art, while simultaneously saving time during inverter replacement. Eliminating the need for pre-configuration also simplifies spare parts logistics.

[0048] A further advantageous function of the cross-communication 2 proposed according to the invention results from the fact that the inverters 10, 20, 30 can exchange measured variables, controlled variables, or quantities calculated in their unit with each other in a temporally synchronous manner. It is already common practice today for a single inverter 10, 20, 30 to determine the condition of hardware components by monitoring measured variables (e.g., threshold detection, testing against a valid value range, long-term evaluation of the average value, Fast Fourier Transforms, etc.), for example, from acquired sensor data or other control variables. This allows the condition monitoring for the individual inverters 10, 20, 30 to be significantly improved.

[0049] By comparing data from multiple inverters 10, 20, 30 operating in the same wind turbine, diagnostics (e.g., for fault detection or optimization of setting parameters) can be improved. Typically, such diagnostics are performed offline by evaluating measurement data from numerous devices in the field at a central location. Cross-communication 2 makes it possible to perform this evaluation virtually online using data from, for example, three inverters 10, 20, 30 connected via cross-communication within the same rotor hub. This diagnostic process is virtually online because the required data is transmitted so quickly via cross-communication 2 that it is available in the inverters 10, 20, 30 almost instantly.

[0050] Each inverter (10, 20, 30) can compare the measured data against the current values ​​or values ​​from a long-term storage system with the values ​​of the two parallel inverters (20, 30 or 10, 30 or 20, 30). For example, it is conceivable to compare measured values ​​(such as temperatures) between inverters 10, 20, 30 to ensure they comply with a tolerance band.

[0051] A measured value from inverter 10, 20, 30 can thus be checked against an expected value based on the measurement data from two other inverters 20, 30 or 10, 30 or 20, 30. This increases the diagnostic depth.

[0052] In another form, it is also possible to exchange diagnostic data with inverters in wind turbines in the same wind farm or the same manufacturer's fleet via an external communication channel, which further increases the diagnostic possibilities.

[0053] The proposed cross-communication 2 also enables rapid local intervention in the pitch control by a pitch drive control unit 10, 20, 30 for only the rotor blade set by the pitch drive control unit 10, 20, 30. This is explained below.

[0054] In the current state of the art, each inverter 10, 20, 30 receives a position setpoint, for example, for the rotational position of the rotor blade, via the central control unit of the wind turbine. If the pitch drive control is to react for a specific rotor position (e.g., when the rotor blade passes the tower of the wind turbine), this must be done by changing the setpoint specified by the central control unit. Due to the delay in the fieldbus transmission (usually used for this purpose), such dynamic adjustments in the pitch drive control are only possible up to a certain limit, since the measured values ​​from inverters 10, 20, 30 must first be obtained by the central control unit, and a new rotational position setpoint must be calculated from them.

[0055] The cross-communication according to the invention enables such intervention in the pitch control of the rotor blades locally within the inverters 10, 20, 30. The latencies of the control due to the duration of the data transmission between the inverters 10, 20, 30 and the central control unit are reduced and the dynamics of the pitch drive control 1 are improved.

[0056] Furthermore, it is conceivable that, for example, measured values ​​from inverters 10, 20, 30 of the rotor blade leading in the direction of rotation could be used for pitch control of the blade lagging by 120° (e.g., predictive load torque feedforward control). The 120° angle results from a preferred embodiment of the wind turbines with three rotor blades arranged at the same angular interval. However, this concept according to the invention is not limited to such a number or arrangement of rotor blades and can be applied arbitrarily.

[0057] Furthermore, it is conceivable that rotor state data could be calculated from the time-synchronized measurement data of the three inverters 10, 20, and 30. One possible approach here is to determine the rotor position or angular velocity from the measurement data of acceleration or current sensors. The evaluation can be performed redundantly and thus functionally reliably using the measurement data from the other inverters 20, 30 or 10, 30 or 10, 20. Additionally, torque or current profiles of the parallel inverters can also be included in the calculation.

[0058] A further advantage of cross-communication 2 arises with regard to safety modules in the inverters 10, 20, 30. Safety functions are implemented within so-called safety modules in inverters 10, 20, 30, which are intended to enable the safe shutdown of the system in the event of malfunctions. For this purpose, the data acquired and processed in the safety modules are often acquired redundantly (i.e., via two channels with, for example, duplicate sensors) and validated, depending on the required safety integrity level. The cross-communication 2 proposed according to the invention allows the necessary redundancy to be established between the inverters 10, 20, 30 connected in the cross-communication network.For this purpose, the safety-relevant measurement data and the values ​​calculated from them are transmitted via cross-communication to the safety modules of the neighboring inverters 20, 30 or 10, 30 or 20, 30 and checked there by a redundant calculation. Methods for checksum calculation can be used for this purpose.

[0059] Cost advantages can be achieved by eliminating redundancy in individual inverters 10, 20, 30, i.e., by using the same sensors multiple times.

[0060] The methods, process steps, or functions described above demonstrate the high value of the cross-communication 2 proposed according to the invention between pitch drive control units 10, 20, 30 provided in a common rotor hub of a wind turbine. Beyond these applications, the proposed cross-communication 2 can also be used effectively in the implementation of further methods, process steps, or functions. Reference symbol list:

[0061] 1 Pitch drive controller 2 Cross-communication 10 Pitch drive control unit trained as an inverter 11 Input interface 20 Pitch drive control unit trained as an inverter 21 Input interface 30 Pitch drive control unit trained as an inverter 31 Input interface

Claims

1. Pitch drive controller of a wind turbine, having a plurality of rotor blades fixed on a rotor hub for rotational adjustment of the rotor blades on the rotor hub by electric motor, wherein the pitch drive controller (1) has at least one pitch drive control device (10, 20, 30) for each rotor blade for actuating at least one pitch drive motor, wherein the pitch drive control device (10, 20, 30) has an electronic actuation unit for the pitch drive motor, a control output to the pitch drive motor and a computing unit with at least one processor configured for operating the pitch drive control device, wherein each of the pitch drive control devices (10; 20; 30) has a local communication connection and is or can be connected to the other pitch drive control devices (20, 30; 10, 30; 10, 20) of the wind turbine in a cross-communication (2) via said local communication connection characterized in that each of the pitch drive control devices (10, 20, 30) has an external communication connection to a central control of the wind turbine.

2. Pitch drive controller according to claim 1, characterized in that the cross-communication (2) is embodied as a field bus communication.

3. Pitch drive controller according to claim 1, characterized in that the cross-communication (2) is embodied as a point-to-point-communication.

4. Pitch drive controller according to any one of the preceding claims, characterized in that the pitch drive control devices (10, 20, 30) of the pitch drive controller (1) are configured to exchange one or more of the data types defined as follows: • setpoints • actual values • measured values • calculated values • operating parameters of the pitch drive control device, including the software status of application software and / or firmware or an installable data processing program with the application software and / or the firmware or software updates • time information • data packets from safety modules5. Pitch drive control device for actuating a pitch drive motor, wherein the pitch drive control device (10, 20, 30) is equipped with an electronic actuation unit, a control output to the pitch drive motor, a computing unit with at least one processor configured to operate the pitch drive control device (10, 20, 30), wherein the pitch drive control device (10; 20; 30) has a local communication connection and can be connected with other pitch drive control devices (20, 30; 10, 30; 10, 20) of the wind turbine in a cross-communication (2) via this local communication connection characterized in that the pitch drive control device (10, 20, 30) has an external communication connection to a central control of the wind turbine.

6. Pitch drive control device according to claim 5, characterized in that the local communication connection comprises a wired electrical and / or optical interface.

7. Pitch drive control device according to either of claims 5 or 6, characterized in that the pitch drive control device (10, 20, 30) includes integrated and / or connectable sensors for capturing measured values, and that the computing unit is configured to process the captured measured values.

8. Pitch drive control device according to any one of claims 5 to 7, characterized in that the pitch drive control device (10, 20, 30) comprises a safety module, in which safety functions are implemented that can be executed on the basis of data captured and processed in the safety module (10; 20, 30), wherein the captured data at least also contains data received from at least one pitch drive control device (20, 30; 10, 30; 10, 20) in the cross-communication (2), wherein the computing unit of the pitch drive control device (10; 20, 30) is configured to evaluate this data in the safety module as well.

9. Pitch drive control device according to any one of claims 5 to 8, characterized in that the computing unit of the pitch drive control device (10; 20, 30) is configured to transmit measured values and / or setpoints and / or calculation values for the rotational adjustment of the rotor blade to other pitch drive control devices (20, 30; 10, 30; 10, 20) connected in the cross-communication (2) and / or to receive them from the other pitch drive control devices (20, 30; 10, 30; 10, 20), and to intervene locally in the pitch drive control (1) on the basis of received measured values and / or setpoints.

10. Pitch drive control device according to any one of claims 5 to 9, characterized in that the computing unit of the pitch drive control device (10; 20; 30) is configured to receive measured values and / or setpoints and / or calculation values from other pitch drive control devices (20, 30; 10, 30; 10, 20) and to check measured values and / or calculation values captured in the pitch drive control device (10; 20, 30) itself against an expected value from the measured values and / or setpoints and / or calculation values received from the other pitch drive control devices (20, 30; 10, 30; 10, 20).

11. Pitch drive control device according to any one of claims 5 to 10, characterized in that the pitch drive control device (10, 20, 30) has an input interface (11, 21, 31) with a user input device and at least one display device.

12. Pitch drive control device according to any one of claims 5 to 11, characterized in that the computing unit of the pitch drive control device (10; 20; 30) is configured to transmit setting parameters of the pitch drive control device (10; 20; 30) and / or an installable image of the software to another of the pitch drive control devices (20, 30; 10, 30; 10, 20) via the cross-communication (2) and to store them in the other pitch drive control system (20, 30; 10, 30; 10, 20).

13. Pitch drive control device according to claim 12, characterized in that the computing unit of the pitch drive control device (10; 20; 30) is configured to retrieve the setting parameters of the pitch drive control device (10; 20; 30) and / or the installable image of the software from one of the other pitch drive control devices (20, 30; 10, 30; 10, 20) via the cross-communication (2) and to set them up in the computing unit of the substituted pitch drive control system (10; 20; 30) when one of the pitch drive control devices (10; 20; 30) of the wind turbine is replaced.

14. Method for controlling a pitch drive controller (1) of a wind turbine according to any one of claims 1 to 4 with at least two pitch drive control devices (10, 20, 30) according to any one of claims 5 to 13, characterized in that the computing units of the pitch drive control devices (10, 20, 30) are configured to communicate with each other and to exchange data with each other and / or store data via the cross-communication (2).

15. Method according to claim 14, characterized in that the computing units of the pitch drive control devices (10, 20, 30) are configured to carry out at least one of the following method steps: • Transmitting and storing the setting parameters of one of the pitch drive control devices (10; 20; 30) and / or an installable image of the software of this one of the pitch drive control devices (10; 20; 30) to another of the pitch drive control devices (20, 30; 10, 30; 10, 20) by means of the cross-communication (2); • Reading out the setting parameters and / or the stored installable image of the software stored in one of the pitch drive control devices (10; 20; 30) by means of the cross-communication (2) and installing them in another of the pitch drive control devices (20, 30; 10, 30; 10, 20); • Receiving measured values and / or setpoints and / or calculation values from other pitch drive control devices (20, 30; 10, 30; 10, 20) by means of the cross-communication (2) and checking a measured value and / or calculation value captured in the pitch drive control device (10; 20; 30) itself against an expected value which is derived from measured values and / or setpoints and / or calculation values received from the other pitch drive control devices (20, 30; 10, 30; 10, 20); • Sending measured values and / or setpoints and / or calculation values for rotational adjustment of the rotor blade to other pitch drive control devices (10, 20, 30) connected in the cross-communication (2); • Receiving measured values and / or setpoints and / or calculation values for rotational adjustment of the rotor blade from the other pitch drive control devices (20, 30; 10, 30; 10, 20) by means of the cross-communication (2) and local intervention in the pitch drive control (1) based on the measured values and / or setpoints and / or calculation values received; • Receiving data also at least from at least one pitch drive control device (10, 20, 30) by means of the cross-communication (2) and evaluating said data in the safety module for the purpose of implementing safety functions.