System Simulation<\/strong><\/p>\n\n\n\n PLC’s<\/strong><\/p>\n\n\n\n Different kinds of PLCs can be used for hydrogen applications, but one of the most advanced solutions is the the SIMATIC S7-1500<\/a> high-performance PLC by Siemens, designed for advanced industrial automation. <\/p>\n\n\n\n Its key features include:<\/p>\n\n\n\n That makes the SIMATIC S7-1500 ideal for manufacturing, process control, energy management, and safety-critical applications, providing reliability, scalability, and security for modern industrial systems.<\/p>\n\n\n\n Then, connecting a physical model to the PLC that will be used in the real system makes it possible to evaluate and optimize controls at early-stage of the projects by:<\/p>\n\n\n\n This finally leads to more efficient, reliable, and cost-effective renewable energy and hydrogen systems.<\/p>\n\n\n\n Any Simcenter Amesim model can be coupled with PLC controllers, either as what we call HiL or SiL.<\/p>\n\n\n\n In HiL, with Siemens Automation, the real PLC exchanges data with the physical simulation model using a simulation unit that is a simulated peripheral. With non-Siemens automation, the real PLC communicates with the physical model using the OPC UA protocol.<\/p>\n\n\n\n In SiL, the PLC automation is simulated (then it is a virtual controller). The data exchange with the physical model in Simcenter Amesim is realized differently depending on the controller type and if it is a Siemens or a non-Siemens automation.<\/p>\n<\/div> System simulation is used to evaluate design options and quickly identify the best architectures of the system, helps to optimize the subsystems sizing and subsystems detailed design and the performance of the system can also be evaluated quickly considering many scenarios. You can predict how much electricity and hydrogen can be produced depending on the power sources sizing, it can be used to assess the best sizing of the energy storage system, even considering batteries ageing. Models can be used to integrate the electrolyzer stack with its Balance of Plant or to design innovative hydrogen storage systems.<\/p>\n\n\n\n Controls can be virtually validated and optimized, and the system is virtually commissioned thanks to a model of the physical system. It includes different levels of controls, from the high-level energy strategy to the component close controls. In the case of a wind turbine, a PLC can be used to optimize the yaw and the pitch of the blades and the generator power generation. With solar panels, controls can be used to adapt the panel’s orientation to the sun’s position. Many components from the electrolyzer Balance of Plant are controlled: the thermal management system with pumps and valves, the water supply system, the gas separation and storage systems\u2026<\/p>\n\n\n\n To address the simulation of green hydrogen production and renewable energies, Simcenter Amesim comes with many features, such as:<\/p>\n\n\n\n Being able to leverage these capabilities will offer engineers several benefits when using system simulation:<\/p>\n\n\n\n Safety<\/strong><\/p>\n\n\n\n Performance and efficiency<\/strong><\/p>\n\n\n\n Virtual Commissioning and digital twin<\/strong><\/p>\n\n\n\n Green hydrogen has been identified as an emerging solution to help decarbonize industries, transportation, and energy storage. But for an acceptability and large deployment of the solution, many challenges remain to be addressed, including:<\/p>\n\n\n\n To demonstrate the capability of Simcenter Amesim to model and simulate the combination of renewable energies with an electrolyzer to produce green hydrogen, a physical model has been developed. This model is composed of several sub-systems including:<\/p>\n\n\n\n Note that using this model to simulate a 1-day scenario usually just takes less than 30 seconds with a conventional laptop.<\/p>\n\n\n\n Thanks to this mechatronic model, simulations can be performed to capture the physical behavior of the different subsystems. We can for instance use it to:<\/p>\n\n\n\n Then, the Simcenter Amesim standalone model that has been used for system design can be used to validate the PLC controls virtually and for virtual pre-commissioning. The controls are just removed from the physical system and replaced by an interface block, making it possible to connect inputs (control requests) and outputs (sensor measurements) to the PLC. The PLC can be real hardware or a virtual PC.<\/p>\n\n\n In our application, a virtual PLC has been generated using PLCSIM Advanced and connected to the Simcenter Amesim model thanks to Automation Connect. Finally, user interfaces have been created with the SIMATIC WinCC Unified System for visualization and interaction with both the physical model and the virtual PLC.<\/p>\n\n\n\n Then, it is possible to launch the simulation from the friendly user interface, which can also be used to visualize the system’s dynamic behavior with plots and animations. From the same interface, it\u2019s also possible to modify the system’s operating conditions manually, such as the wind velocity and orientation of the ambient temperature. The parameters of the control strategies could also be tuned to improve control calibrations and system performances.<\/p>\n\n\n Fuel cell vehicles are starting to be more and more deployed, including mainly passenger cars but also trucks and buses. Combustion engines for buses & trucks could also burn hydrogen instead of gasoline or diesel. One of the limitations of a larger deployment of hydrogen vehicles (on top of the price, the life expectancy of the components, and the hydrogen storage\u2026) comes from the fact that the hydrogen distribution network is still almost nonexistent. Several regions already started to deploy a larger number of hydrogen refueling stations in big cities and along the main highways and still have the plan to further extend the number of H2<\/sub> dispensers.<\/p>\n\n\n\n One of the challenges with hydrogen refueling stations is to make it possible to refuel a vehicle in no longer time than for a conventional combustion engine vehicle. For a passenger, a 5-minute refueling time would be acceptable, while for a truck with a larger tank, 10 to 15 minutes would also be satisfactory. Finally, to make hydrogen refueling stations profitable, it is important to reduce the APEX and OPEX as much as possible. So, the system has to be designed with the best selection, design, and sizing of the components to contain the investments. The energy that will be consumed by the system, mainly for compression but also for thermal management, must be controlled and reduced as much as possible.<\/p>\n\n\n\n To demonstrate the capability of Amesim to model and simulate a hydrogen refueling station, a physical model has been developed. It has already been introduced in a blog article<\/a>.<\/p>\n\n\n\n
Enhancing efficiency and reducing costs by finding the best configurations and operations.<\/li>\n\n\n\n
Ensuring smooth integration of renewable sources and hydrogen into energy systems.<\/li>\n\n\n\n
Assessing and minimizing environmental impacts.<\/li>\n\n\n\n
Evaluating financial viability and supporting investment decisions.<\/li>\n\n\n\n
Aiding policymakers with data for effective regulations and standards.<\/li>\n\n\n\n
Accelerating development and deployment of new technologies.<\/li>\n\n\n\n
Predicting performance under various conditions to develop robust contingency plans.<\/li>\n<\/ul>\n<\/div>\n\n\n\n\n
PLCs manage the precise control of electrical current, water flow, and voltage in electrolyzers, optimizing hydrogen generation and ensuring safety by monitoring pressure and temperature.<\/li>\n\n\n\n
They control hydrogen compressors and monitor pressure, temperature, and flow rates in storage tanks, ensuring safe and efficient operation.<\/li>\n\n\n\n
PLCs regulate hydrogen flow, air supply, and power output in fuel cells, ensuring optimal performance in energy generation or vehicles.<\/li>\n\n\n\n
PLCs automate the refueling process for hydrogen-powered vehicles, controlling flow and pressure to ensure safe and efficient fueling.<\/li>\n\n\n\n
They manage hydrogen pipelines, regulating flow and pressure while detecting leaks to prevent accidents.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n\n\n\n\n
Fast processing speed for complex automation tasks like motion control and real-time processes.<\/li>\n\n\n\n
Flexible configuration with various CPUs, I\/O modules, and communication interfaces to suit diverse applications.<\/li>\n\n\n\n
Built-in safety functions for controlling both standard and safety-critical tasks in compliance with safety standards.<\/li>\n\n\n\n
Supports multiple industrial protocols such as PROFINET and Profibus for seamless system integration.<\/li>\n\n\n\n
Built-in display and advanced diagnostics for easy troubleshooting and system monitoring.<\/li>\n\n\n\n
Supports direct control of motors and process variables with integrated motion and PID control.<\/li>\n\n\n\n
Simplifies programming and configuration through the Totally Integrated Automation (TIA) Portal<\/a>.<\/li>\n<\/ul>\n<\/div>![\"SIMATIC](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image003-1024x576.jpg\")
<\/a><\/figure><\/div>\n\n\n\n\n
Simulating various operational conditions to identify the best control strategies.<\/li>\n\n\n\n
Enhancing efficiency and stability by being able to consider the performance of an entire system<\/li>\n\n\n\n
Finding optimal control settings without physical trials<\/li>\n\n\n\n
Identifying potential issues and mitigating risks through virtual testing.<\/li>\n<\/ul>\n\n\n\n![\"Virtual](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image005.jpg\")
<\/a><\/figure><\/div>\n\n\n\nHydrogen systems simulation with Simcenter Amesim<\/h2>\n\n\n\n
How system simulation can help with renewables and green H2 production<\/h4>\n\n\n\n
Simcenter Amesim capabilities<\/h4>\n\n\n\n
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Use case 1: Using renewables and electrolysis to produce green hydrogen<\/h2>\n\n\n\n
Design main challenges<\/h4>\n\n\n\n
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Simcenter Amesim standalone model for system design<\/h4>\n\n\n\n
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Makes it possible to define fluctuating wind speed and orientation using real meteorological data or user-defined values.<\/li>\n\n\n\n
This subsystem model considers the wind speed and orientation, the wind turbine propeller characteristics, the transmission ratio, the generator, and power electronics to evaluate the dynamic power generated by the wind turbine. Several components are controlled including the propeller pitch angle and the generator.<\/li>\n\n\n\n
this one is used to align the wind turbine with the wind direction using 6 electric motors, a transmission, and a brake. Both the electric motors and the brake are controlled.<\/li>\n\n\n\n
A battery has been integrated into the system to absorb peaks of power generated by the wind turbine that exceeds the power that can be used by the electrolyzer. The battery can also help reduce electrolyzer power dynamics to improve performance and reduce degradation. Finally, the charged battery makes it possible to keep the electrolyzer running even when the wind stops blowing.<\/li>\n\n\n\n
That includes a PEM electrolyzer electrochemical model, but also the DC\/DC converter used to control energy flows between the electrolyzer and the battery, a water pump used to recirculate water at the electrolyzer anode side and manage the electrolyzer thermal behavior. The pump velocity is controlled to maintain the electrolyzer in the right range of temperature when a heat exchanger is removing heat from the fluid and a by-pass valve is controlled to by-pass the heat exchanger when the electrolyzer is cold. This model can capture the H2<\/sub> and O2<\/sub> gas production and the water consumption as well. It also predicts the electrolyzer performances including the electrical power consumption and the heat losses generating its temperature evolution.<\/li>\n<\/ul>\n<\/div>![\"Simcenter](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image009.png\")
<\/a><\/figure><\/div>\n\n\n![\"Electrolyzer](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image011-600x301.png\")
<\/a>Example of simulation results<\/h4>\n\n\n\n
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![\"Simulation](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image014.png\")
<\/a>![\"Simulation](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image016.png\")
<\/a>![\"Simulation](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image018.png\")
<\/a>Connection of the system model to the PLC controller for control design and pre-commissioning<\/h4>\n\n\n\n
![\"Connecting](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image019-1024x427.png\")
<\/a>![\"Wind](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image021-1024x393.png\")
<\/a>Use case 2: Hydrogen refueling station<\/h2>\n\n\n\n
Design main challenges<\/h4>\n\n\n\n
Moreover, quickly compressing hydrogen generally raises its temperature. If the hydrogen comes to the tank with a temperature that exceeds values (usually 85\u00b0C) that could damage the tank materials. Then, several standards regulate the temperature limits for hydrogen when refilling a vehicle tank. And on top of that, for safety issues, flows and pressures must also be carefully monitored.<\/p>\n<\/div>![\"Hydrogen](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image023.jpg\")
<\/figure><\/div>\n\n\n\nSimcenter Amesim standalone model for system design<\/h4>\n\n\n\n
![\"Hydrogen](\"https:\/\/blogs.sw.siemens.com\/wp-content\/uploads\/sites\/6\/2024\/09\/image025-1024x275.png\")
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