Transmitting high power efficiently over long distances
Interview with Dr. Fabian Assion
Power generation and distribution companies are facing huge challenges: renewable forms of energy need to be integrated, which means that flexible solutions are required to accommodate feed-in fluctuations. At the same time, there is a growing demand for extensive grid expansion and the modernization of existing infrastructure in order to move away from conventional distribution grids and toward smart grids. Increased use of automation and measurement technology is vital for achieving an efficient energy transfer. We offer innovative solutions to enable both the transparent recording of all energy flows and the control of energy systems.
Your head start in energy technology with Beckhoff:
- a seamless energy measurement chain from the sensor to the cloud
- easy-to-install plug-in power sensors
- comprehensive software modules for power measurement and control
- Decades of experience in renewable energy and the associated feed-in process:
- control of more than 130,000 wind turbines
- PC-based converter technology
- grid simulation
At a glance: The energy supply of the future
Future-proof automation for renewable energy
Renewable energy is essential for the energy transition. However, as these forms of energy depend on external factors, such as the sun and the wind, they need flexible control technology and efficient storage solutions. Beckhoff has extensive experience in automating renewable forms of energy; more than 130,000 wind turbines have already been automated using Beckhoff control technology. Our solutions cover all functions, from operational management, pitch control, and the yaw system through to vibration monitoring, as well as farm networking. Specific software frameworks are used not only for wind energy, but also for controlling tidal turbines. Furthermore, Beckhoff technology can be found in a vast array of applications, such as solar plants, hydroelectric power stations, geothermal and biogas plants, the hydrogen industry, and electromobility.
All functions are integrated into a single platform, creating a flexible foundation for future-ready automation. These include open-loop and closed-loop control, condition monitoring, visualization, cloud connectivity, explosion protection, and safety and measurement technology. The open interfaces and support for IEC 61850 enable both conventional and renewable energy sources to be integrated into a common automation platform.
Why do we need the smart grid?
Up until a few years ago, energy only flowed in one direction through electricity grids: from generation in the extra-high and high-voltage ranges to loads in the medium and low-voltage ranges. This has now changed due to the increased share of renewable energy, meaning that energy flows have become bidirectional, generation is decentralized, and supply is uneven, which can lead to overload and instability. While conventional power plants use synchronous generators, renewable energy sources rely on inverter-controlled systems, making regulation within traditional grids a more dynamic process. Smart grids offer a solution: by providing comprehensive information on the grid’s status, they facilitate its regulation and are therefore fundamental to creating a stable and sustainable energy supply for the future.
Beckhoff offers suitable automation technology for intelligent distribution grids: EtherCAT enables precise communication with the I/O modules that are required to measure voltage and current in transformer stations and local distribution substations. Open interfaces facilitate integration into existing grid management systems. Smart grid functions can be integrated directly into the control system, enabling dynamic adaptation to changing load conditions.
Efficient energy transfer
Energy needs to be transferred efficiently and with minimal losses in modern power supply systems. Beckhoff technology is used in conventional alternating current (AC) transmission systems, as well as in technologies such as high-voltage direct current (HVDC) transmission and flexible alternating current transmission systems (FACTS), which help to stabilize and optimize grid performance. The high performance of the Beckhoff control platform enables precise regulation of converter stations and power electronics. With EtherCAT, millions of measured values from I/O modules can be processed in real time to optimize line monitoring and protection mechanisms.
Beckhoff systems are scalable, allowing flexible adaptation to different transmission requirements, from individual lines to distributed grids. The ability to transfer data to the cloud securely supports real-time analysis and the development of preventive maintenance concepts. As a result of the comprehensive software solutions, even sophisticated applications, such as modular multilevel converters (MMC), can be efficiently controlled and monitored.
Energy storage systems ensure grid stability
Energy storage systems (ESS) store energy from the grid or renewable energy sources and release it again when required. This allows energy production and consumption to take place at different times. The integration of energy storage systems enables a wide range of applications, such as grid stabilization, frequency and voltage regulation, demand response, and the integration of renewable energy. The increased volatility and reduced inertia in the grid pose a major challenge here due to the need to respond rapidly to grid disturbances. The high responsiveness of battery storage systems makes them particularly suitable for grid services such as frequency regulation and voltage stabilization.
Beckhoff offers a unified automation platform for energy storage systems, Power-to-X applications, and hydrogen systems. Powerful PCs enable precise control of charging and discharging processes, and allow monitoring of the battery status. Open interfaces mean that different storage technologies can be easily integrated and synchronized with the grid. Comprehensive software tools not only make it possible to optimize load and storage capacities, but also to use historical data for forecasting models.
Linking the players in the All Electric Society via PC-based control
In order for energy distribution to be successfully modernized, effective communication must be established between all the players in the electricity grid: conventional power plants, renewable energy generation facilities, and local systems that can consume, store, or feed in energy. Efficient networking in systems and bidirectional connectivity are crucial for decentralized systems to be able to feed power back into the grid.
Hybrid power plants (HPP) combine power generation with storage solutions at a single location and are operated as one unit. HPPs have integrated control over each system, which is optimized according to specific requirements and environmental conditions. By contrast, a local energy system (LES) controls power generation and storage in a defined geographical area, e.g., a city district. LES control focuses on balancing local generation and demand, often using more straightforward energy management systems.
Due to its high level of connectivity, PC-based control simplifies the process of networking power generation systems with control centers and grid operators. Flexible fieldbus connectivity and the integration of telecontrol protocols such as IEC 60870-5-10x and IEC 61850 enable remote monitoring and operational optimization.
Minimizing switching losses with PC-based converters
A multilevel converter (MMC) consists of numerous submodules (often half bridges or full bridges) that are connected in series to produce a stepped output voltage. This structure makes it possible to generate near-sinusoidal voltages with minimal harmonic distortion. This reduces switching losses and increases efficiency. The many submodules generate near-sinusoidal voltages while minimizing harmonic distortions. MMCs respond dynamically to grid fluctuations, supply active and reactive power, and are ideal for renewable energy sources, battery storage facilities, and HVDC systems. MMCs increase overall efficiency by reducing losses, offering high scalability, and ensuring excellent fault tolerance, as defective submodules can be isolated.
EtherCAT enables high-precision control and fast communication in MMCs, factors which are crucial for power control and energy conversion. Further advantages of PC- and EtherCAT-based converters are that they minimize harmonics, improve power quality, adapt quickly to grid fluctuations, and are highly efficient.
Our technologies for electrical power distribution
A unified automation solution for energy technology
With its PC-based control, Beckhoff offers a unified automation platform that is perfectly tailored to the requirements of power generation companies and grid operators. The focus here is on openness and scalability, flexibility in the design of the controller, and a high degree of integration.
The job of the controller is performed by industrial PCs running the TwinCAT automation software. TwinCAT offers modular software blocks, including special software for the energy sector. EtherCAT I/Os enable comprehensive integration of all common signals and sensors, including in the field of energy and power measurement. EtherCAT, the high-speed fieldbus developed by Beckhoff, allows seamless communication from the sensor to the cloud.
The highlights of PC-based control at a glance:
- integrated control platform for PLC, visualization, safety and measurement technology
- modular expandability
- reduced hardware and engineering costs
- openness to third-party providers
Fast and synchronized at the highest sampling rates
Outstanding performance and simple configuration are the hallmarks of EtherCAT – the Ethernet-based real-time technology from Beckhoff. EtherCAT not only offers incredibly fast cycle and synchronization times, but also a high bandwidth for data-intensive measurement applications. With this outstanding performance, EtherCAT enables efficient energy management from the wind turbine to the local distribution substation.
The highlights of EtherCAT at a glance:
- extremely fast cycle times for precise and efficient processes
- maximum performance at speeds of 1 Gbit/s or 10 Gbit/s (EtherCAT G10)
- high measurement quality due to timestamps, distributed clocks, and oversampling
- synchronicity of < 1 µs
- wide choice of EtherCAT-compatible sensors and actuators
- flexible integration of other fieldbus systems
Modular automation software
The TwinCAT 3 automation software integrates all engineering and runtime processes, and features a unified development environment for implementing all control and measurement tasks in electrical energy systems. Programming is carried out using the most appropriate method for the application, including IEC 61131-3, high-level languages such as C/C++, MATLAB®, and Simulink®. Microsoft Visual Studio is used as the standard programming workbench, since it not only supports version management, but also simplifies teamwork. Ready-made software blocks facilitate engineering and shorten development and commissioning times.
The TwinCAT highlights at a glance:
- high-performance real-time platform supports cycle times of 50 µs and faster
- ready-made software blocks and functions simplify engineering
- special libraries for energy and power measurement
- diverse options for data storage and evaluation
Our product highlights for electrical power distribution
Mastering the energy transition with integrated measurement technology
Beckhoff offers a cost-optimized solution for recording power distribution energy flows in the form of its easy-to-retrofit power sensors and the EL3475 EtherCAT measurement terminal. This allows users to swap their analog measuring devices for hinged current and voltage transformers, providing them with a seamless measuring chain for monitoring, analyzing, and optimizing processes. Power measurements can be performed at all outgoing feeders, thereby creating transparency for distribution grid operators.
The highlights at a glance:
- precise measurement of all relevant electrical data in a distribution grid
- quick installation thanks to pluggable connection concept (RJ45)
- efficient commissioning with pre-assembled cables for voltage transformers (SVL) and current transformers (SCL)
- simple implementation because the transformers have electronic nameplates to avoid configuration errors (e.g., when setting the transformer ratios)
- determination of grid status and grid transparency in accordance with Section 14a of the German Energy Industry Act (EnWG)
Integrated power and energy measurement technology
There is a wide variety of requirements for energy management in the energy sector, ranging from pure grid monitoring and process control through to high-end power monitoring. The power and energy measurement terminals focus on different aspects and are therefore designed for a wide range of applications:
- EL3443 and EL3453: High-feature applications for 3-phase networks, internal preprocessing of current and voltage values, provision of up to 600 values for network analysis in the controller
- EL3773 and EL3783: Network monitoring with oversampling function, simultaneous measurement of current and voltage on all channels at up to 10 ksps
- EL3446, EL3444 and EL3443: Distributed power measurement with as many EL3446/EL3444s as required and one EL3443 per network. With spatially separated current/voltage measurement, real power data can be determined.
In addition to EtherCAT Terminals, the power measurement portfolio also includes current transformers which have optimum compatibility with the I/Os and a software library for monitoring with TwinCAT. Suitable accessories are available for additional safety in the control cabinet. This results in a complete package: all components can be procured from a single source.
Power measurement with TwinCAT
TwinCAT Power Functions are a set of modules in TwinCAT that can be used to implement various applications in the field of power measurement. They provide solutions for power supply systems in the form of software modules for 3-phase AC systems. The overall system has a modular and adaptable architecture, and the pre-built drivers make it ready for immediate use. No programming or compilation is required.
TF8330 TwinCAT Power Collector: Provides software blocks for programming power measurement applications. The modules offer a standardized interface for all terminals in the EL34xx series. Parameters such as the transformer ratio and frequency range can be configured automatically. Interfaces for the latest transmission protocols – such as MQTT, HTTP REST, and OPC UA – are implemented.
TF8350 TwinCAT Power Technologies: This feature provides software blocks for programming in-depth diagnostics for electrical power measurement based on the EL37x3. What’s more, it offers the same standardized interface as the TF8330. Real-time optimized calculations of the RMS values, frequency, harmonics, distortions, etc., are continuously provided in a cycle of 1 ms. Advanced frequency determination methods and an instant Clarke/Park transformation are included.
In combination with the EL3783 and EL6689, the TF8350 can be used to implement a phasor measurement unit that enables time-synchronous and precise phase measurement in distribution and supply grids in accordance with IEC 60255-118-1.
TF8360 TwinCAT Power Control: Provides software blocks for implementing a power plant controller. This is required for all power-generating systems in order to meet the grid requirements. And it meets the standards of the individual European countries, e.g., VDE-AR-N 4110/4120 in Germany.
The relevant software modules include:
- a reactive power controller for voltage stabilization
- active power control for frequency stability
- fault ride through capability
Energy monitoring with TwinCAT Analytics
The TwinCAT Analytics product family provides a complete workflow for energy monitoring in distribution grids – from data acquisition, communication, and data historization to analysis and visualization via web-based dashboards. Various algorithms are available for analyzing both live data and historical data.
The highlights at a glance:
- software tool for seamless data recording and analysis
- graphical display of analysis results via interaction with TwinCAT Scope View
- data streaming from the machine via MQTT
- simple drag and drop function
- seamless integration of condition monitoring functions
Connectivity for the smart grid
With its outstanding connectivity, PC-based automation simplifies the process of networking power generation systems with control centers, grid operators, and municipal power suppliers. Telecontrol protocols according to IEC 60870-5-10x and IEC 61850 can be installed as a library of the TwinCAT automation software, facilitating remote monitoring and operational optimization.
Connecting to the cloud and providing data through OPC UA makes energy monitoring more transparent while ensuring secure data access for different user groups. Other protocols, such as MQTT or Modbus TCP, can also be flexibly integrated with TwinCAT IoT.
More information
Smart grids
Ensure intelligent energy distribution with transparent monitoring of availability and demand.
Power generation
Control and monitor power plants, wind farms, solar plants, and hydrogen production efficiently with PC-based control.
Wind turbines
More than 125,000 wind turbines worldwide up to a size of 16 MW have already been automated with Beckhoff technology.
Hydrogen industry
Innovative control systems for the efficient and flexible automation of hydrogen plants