Universal control platform for wind turbines

The Beckhoff control architecture is perfectly suited to the requirement profile of the wind energy industry: openness and scalability, flexibility in the design of the controller and a high degree of integration. For all product ranges, from the Industrial and embedded PCs, control panels and I/O components to the automation software, Beckhoff offers modular solutions with precisely scalable performance. Interfaces for all common fieldbuses and the large signal variety of the Beckhoff I/O modules cover all types of signals and fieldbus systems that are relevant to wind power. The user can configure a performance-related controller for the specific wind turbine using Beckhoff standard components. Subsequent extensions and modifications are also possible at no great cost thanks to the modularity of this solution. The integrated PC-based control platform eliminates the black boxes of hardware-based safety or monitoring solutions and ensures the efficient interaction of all system components. The advantages for the users are the increased availability and thus the efficiency of their wind turbines as well as a reduction in hardware and engineering costs. In addition, the smooth interaction of the Beckhoff technology with industrial communication standards such as IEC 61400-25, Ethernet TCP/IP and OPC guarantees a high investment security for the user.

With PC-based control, you benefit from:

• a universal control platform for operational management, pitch control, farm networking and yaw system
• high flexibility when it comes to controller design
• performance-related scalability
• modular expandability
• reduced hardware and engineering costs
• increased efficiency and cost-effectiveness
• improved competitiveness

Embedded PCs for wind turbines: Robust, fanless and high performance

As a key component of the wind turbine control system, it is possible to use the embedded PCs developed and produced in-house by Beckhoff. The CX device series combines the worlds of industrial PC and hardware PLC and is suitable for control tasks in any power range. All devices in the CX series are specially designed for industrial use, i.e. they are shock and vibration-resistant, EMC-optimized and usable in the extended temperature range. Directly mountable on the DIN rail in the control cabinet, the embedded PC can be expanded as required by adding EtherCAT I/O modules. The fanless construction and easily exchangeable storage media enable low-maintenance use.

The embedded PC portfolio offers various processor classes: from the single-chip system through to the multi-core server CPUs with dedicated GPU. In addition to this there are the options for diverse components, such as main memory, storage media, interfaces and operating system in order to employ the optimal configuration for each application with the best possible price-to-performance ratio.

Based on its own motherboard and BIOS development as well as in-house production, Beckhoff is able to use CPUs and components that are available as embedded components for at least 10 years. Afterwards, a service period of a further 10 years commences. During this time, Beckhoff customers can obtain spare devices or spare parts, by which a service life of at least 20 years on the market is covered.

EtherCAT Terminal system for efficient input and output signals as well as subordinate fieldbus systems

The EtherCAT fieldbus enables high-performance communication over Ethernet. Communication is consistent, without the use of couplers or converters, over copper and fiber-optic cables with all devices. At the same time, every connection, every transformer and every device can be monitored and diagnosed in detail to detect any malfunction immediately and determine the cause.

Due to the wide range of fieldbus components, I/O terminals can be freely distributed as EtherCAT slaves and integrated in the system using any given topology. The comprehensive choice of I/O terminals ranges from recording simple digital and analog signals through to the precise measurement of vibrations, temperatures or strains, thus enabling almost any number of sensors to be connected. Actuators, drives and hydraulic systems can equally be controlled via output signals, however. Subsystems are simply integrated via subordinate fieldbus systems, which are integrated with the EtherCAT system by means of communication terminals in the field.

In this respect, the fieldbus and I/O components are not only available in protection rating IP20, for DIN rail installation, but also in IP65, for installation directly on the machine. This allows the I/Os to be positioned in the control cabinet as required or directly on the sensors and actuators, such as on the gear unit, on the generator or in subsystems like a hydraulic unit.

TwinCAT as an automation and runtime environment for operational management

The automation environment, TwinCAT 3, is integrated in Microsoft Visual Studio and allows the development of the application software according to the programming languages under IEC 61131-3, including the object-oriented extensions. Development in C/C++, integration of algorithms directly from MATLAB^®/Simulink^® or any combination of these options is also available. The TwinCAT modules developed in this way can be freely combined with each other and executed in the runtime environment on an Industrial PC or Embedded PC. In doing so, the I/O components are also connected in modular fashion and freely linked with the TwinCAT modules in the software. The developed software modules are independent of the hardware used and can be used on a wide variety of CPUs, as well as combined with a wide variety of I/O components and fieldbus systems.

Open interfaces into the field – to higher-level systems and into the cloud

The open and modular interfaces of TwinCAT 3 not only support the internal communication and the communication to the I/Os, but also the connection of subordinate or higher-level systems. This allows subsystems or parallel systems as well as monitoring systems to be directly connected by means of EtherCAT or via fieldbuses such as CANopen, PROFIBUS and PROFINET. But the integration in a wind farm using fieldbus systems, such as EtherCAT or PROFINET, or the connection to a SCADA system via protocols such as Modbus TCP, OPC UA and via the telecontrol protocols IEC 60870, IEC 61850 or IEC 61400-25 are easily possible due the openness of the platform. Over and above this, IoT technologies can be used to collect data from a large number of distributed systems, to communicate these, for example, via MQTT or write them directly to a database via e.g., SQL, to also manage fleets and implement cloud scenarios.

TwinSAFE integrates the safety chain with the operational management and the EtherCAT system

The TwinSAFE safety solution is used to seamlessly integrate the safety precautions required in wind turbines with the operational management and the PC-based automation. The I/O terminals for the safety-related communication as well as the integration of safety-relevant sensors and actuators can be easily distributed in the EtherCAT system or arranged in the terminal segment. This means that no additional cabling is necessary, as well as no other components between the nacelle and base of the tower, since the existing EtherCAT connection is simply used also for transferring the safety-related signals.

A programmable logic can be used to create logic links between the secure I/Os and implement the corresponding applications by means of safety function blocks.

TwinCAT 3 Wind Framework: Complete software package for the automation of wind turbines

The modular software package includes all necessary functions and tools for the modern and efficient engineering of wind turbines. In TwinCAT 3, all basic functions are encapsulated in simple-to-use function blocks. They provide a modular range of components for the programmer to choose from, simplifying the development of the application software. Apart from basic functions for operational management and state machine, there are software function blocks for event management, parameter configuration, user management, data connection, power and condition monitoring and simulation. The integrated Big Data database link enables the comprehensive acquisition, evaluation and provision of data from operational management, condition monitoring and power management in real-time. All this data is continually recorded, accumulated in the central controller and evaluated. For example, wear and tear on individual components of the wind turbine installation – which could otherwise lead to an outage – can be detected at an early stage, thus increasing the availability of the system. Each of the prefabricated software modules and application templates has been tried and tested, and shown to be of high quality and future-proof. Individual software modules can be added or removed – in the same way as hardware modifications are carried out. This makes the engineering process as simple as possible, so that developers can focus on the actual system functions.

Development work can also be optimized by subdividing the team: customized modules can be developed and tested in parallel, which further reduces your time-to-market. The consistent use of TwinCAT modules and the uniform architecture of the subsystems creates a standard in the application. This standardization enables programmers to quickly familiarise themselves with the application and the source code, even if it was implemented by another programmer.

The TwinCAT 3 Wind Framework offers:

• future-proof standard application software
• maximized ease of engineering
• secure and efficient software development
• increased software quality and optimized reusability
• significantly reduced time-to-market
• in-depth monitoring and interaction
• continuous acquisition and evaluation of signals
• use of Industrie 4.0 features in wind energy

Also for extreme temperatures and loads: Beckhoff standard components

Over the years, Beckhoff has continued to expand its portfolio of control systems. In the meantime, all Embedded PCs in the CX5xxx, CX20x0, CX9xxx and CX8xxx series are approved for the extended temperature range from -25 °C to 60 °C. In the same way, all the I/Os required to control a wind turbine (EtherCAT Terminals and bus terminals) meet these temperature requirements. In addition, Beckhoff offers terminals with extended surge protection for particularly sensitive EMC areas in the wind turbine.