Efficiency Through Single Source Technology

  Enquiry / contact me

Harmonized drive and automation technology for large bearing test stand


Large bearings with an external diameter of up to 3.5 m are tested under realistic conditions on the world's largest large bearing test stand from Schaeffler.
Large bearings with an external diameter of up to 3.5 m are tested under realistic conditions on the world's largest large bearing test stand from Schaeffler.
The optimum function of the large bearing test stand is accomplished by the perfect interaction of drive and automation components from Siemens.
The optimum function of the large bearing test stand is accomplished by the perfect interaction of drive and automation components from Siemens.
Highlight of the overall solution is the wireless data transmission via Industrial Wireless LAN (IWLAN) and an RCoax radiating cable.
Highlight of the overall solution is the wireless data transmission via Industrial Wireless LAN (IWLAN) and an RCoax radiating cable.
All setup processes of the large bearing test stand can take place without wires and securely thanks to a wirelessly connected Mobile Panel.
All setup processes of the large bearing test stand can take place without wires and securely thanks to a wirelessly connected Mobile Panel.
Rugged and powerful products increase reliability and availability of the system.
Rugged and powerful products increase reliability and availability of the system.

To simulate the complex, wind-driven behavior of offshore wind turbines of the multi megawatt class in a very realistic setting on the world's largest test stand for large bearings located at Schaeffler in Schweinfurt, perfect interaction between the components and systems used in these turbines is required. This interaction is provided by a fully integrated drive train that is seamlessly integrated into the automation and communication technology specifically selected for this task.


Schaeffler Technologies AG & Co. KG in Schweinfurt is a leading manufacturer of roller bearings and precision components for customers in the areas automotive, industry and aerospace. In addition to the classical fields of application in the industrial environment, the Industry division of the company has successfully developed and manufactured bearings for wind turbines for more than 30 years. To test these turbines under very realistic conditions, Schaeffler decided to develop a 6 MW large bearing test stand that is considered one of the most technologically advanced, largest and most powerful large bearing test stands in the world. It can be used to test large bearings weighing up to 15 tons with an external diameter of up to 3.5 meters that are predominantly used in wind turbines with the help of a comprehensive simulation program.
Reliability and availability are crucial for the efficiency of such wind turbines - especially in the offshore sector. The same is true for the drive and automation solution. Siemens was involved as a technology partner starting with the design phase of the test stand. The customer was won over by the total concept including the communication solution with Industrial Wireless LAN (IWLAN) as well as the supplied components.

Reliable drive technology creates realistic wind situations
The main load (with 150,000 Nm) is carried by an integrated drive train based on Siemens components, consisting of a gearbox from the Flender series, a motor from Loher and a cabinet-type frequency converter of the Sinamics S150 family. The gearbox is extremely rugged and thus ensures the high availability of the entire drive train. The drive motor and the Sinamics S150 frequency converter are also very dependable. Loher motors can be customized to meet the individual application.
The specific speed specifications were important for the large bearing test stand "Astraios", and the motor had to be specifically designed to meet these required values: These are 625 min-1 that have to be converted into the 12.5 min-1 typical for wind turbines at an average main load - while providing a wide speed setpoint range of nearly 3,000 min-1. The Loher motor itself provides 300 kW and is water-jacket cooled, mainly to avoid additional heating of the room. The regenerative Sinamics S150 converter precisely and dynamically controls the motor speed and the resulting reaction times which correspond to the behavior of the rotor in case of a change in wind force. Regenerative means it feeds the brake energy that is generated when braking the rotor in the simulation back into the power supply. This is of course much more energy-efficient than dissipating the released energy in a braking resistor in the form of heat as it is frequently done.
Every aspect of the entire drive train consisting of gearbox, motor and frequency converter is matched to the special requirements of the large bearing test stand, such as an integrated emergency stop that ensures safe braking within seconds. The drive technology from Siemens is not only responsible for simulating the main load, but also for the auxiliaries, such as the hydraulic pumps. These simulate the changing and irregular effect the wind has on the rotor and create dynamic pitching and yawing moments (see text box). Three water-cooled motors from Loher with 160 kW and controlled by Sirius soft starters are used for this purpose. Simotics SD low-voltage induction motors are used for the twelve lube oil pumps. These are controlled and coordinated by Sinamics S120 converters for multi-motor drives. The harmonized interaction of the drive components in all test stand applications increases reliability and efficiency.

Perfect interaction of drive and automation technology
The interaction of components and systems is not limited to the drive technology in the large bearing test stand "Astraios". The integrated drive train fits seamlessly into the automation landscape of the test facility. It communicates continuously and very quickly with the controllers of the Simatic S7-300 family using of PROFINET to output, among other things, the exact setpoint value specifications to the drives for simulation of the changing wind conditions.
A Simatic S7-319 is used as main controller in the control cabinet, serving as higher-level controller of the main drive as well as for additional systems, such as a wireless solution. Another fail-safe controller of the same product family is installed in the control cabinet; it is responsible for the safety-related communication of the controllers with the individual areas (hydraulics, lubrication, etc.). The controllers are very powerful so that even complex tasks can be executed in real time. Components of the Simatic ET 200 distributed I/O are used at the field level. They communicate with the different actuators and sensors and are directly linked to the controllers.

Communication takes place via PROFINET and PROFIsafe. PROFINET transmits process-related and safety-related information in real time using the same bus. This reduces additional wiring effort and therefore costs. PROFINET also allows for central diagnostics of each individual device in the field. Errors can be detected and addressed in time. PROFIsafe ensures that the system runs safely for man and machine, which is particularly important for rotating parts. The system can be stopped immediately by means of the fail-safe controllers and the emergency stop function.

Wear-free transmission of measured data with Industrial Wireless LAN
Communications design was a key challenge for the rotor test stand. The requirements not only call for wear-free transmission of measured data of different temperature values of the rotating specimen but also for convenient, mobile and safe control and monitoring of the test stand including safety functionality in the entire area around the system. Two independent wireless networks form the basis of meeting this requirement.
The objective of measured data transmission is to capture the temperature values, velocity and bearing forces of the rotating specimen and to transmit these values to the main controller via IWLAN. The Simatic ET 200pro distributed I/O system collects the measured values of the sensors in this process and transmits them to the control room. A Scalance W788-1RR access point on the stationary part of the system is responsible for wireless data transmission; together with an RCoax radiating cable it forms a defined RF field. Its counterpart is the Simatic ET 200pro with the IWLAN interface module on the rotating bearing test stand; it uses an RCoax directional antenna to transmit the signals. The required WLAN availability for transmission of measured data can be guaranteed by the RCoax special antenna even at rotational speeds of up to 60 min-1. The wear-free and almost maintenance-free IWLAN solution without collector rings guarantees reliable data transmission and helps optimize overall costs.

Safe control and monitoring with Mobile Panel and IWLAN
The Mobile Panel Simatic MP 277F IWLAN is used for control and monitoring including safety functionality. Despite the vast dimensions of the rotor test stand, uninterrupted operation including emergency stop functionality is made possible by Rapid Roaming (iPCF-MC). This means the operator can move around freely within the defined range of the system - without cables and during operation.
This means the operator always has the best view of the system. In addition to convenient operation, the mobile solution meets the safety guidelines specified for systems with rotating parts. This unique solution from Siemens won the customer over immediately. A requirement for reliable communication was to set up an optimum RF field in the vast operating range of the machine that also had a lot of corners. For this reason, the wireless solution for the Mobile Panel was simulated with Sinema E and optimized in the process. The successful computer simulation showed us that two access points of the Scalance W788-2RR series were sufficient for optimal wireless coverage. iPCF (industrial Point Coordination Function) ensures that the wireless connection to the Mobile Panel is always guaranteed even during radio cell change between the two access points.

Integrated overall solution results in highest customer satisfaction
Schaeffler is very pleased with the integration, high availability and reliability of the systems supplied by Siemens. The interaction among all drive and automation components is perfect and considerably minimizes the amount of engineering required. There have been no failures since the system was commissioned. The engineer in charge of the project emphasizes the good cooperation: "Siemens experts were always available to answer any questions we had regarding drive and automation topics. We are very pleased with the cooperation and the entire solution", emphasizes Mr. Reinhold Korn, Technical Director Electrical/System Technology for Test Stand Construction at Schaeffler in Schweinfurt.

Posted on September 10, 2013 - (662 views)
Siemens AG
Gleiwitzer Str. 555
90475 Nürnberg - Germany
View full company profile
More products from this supplier
According to Siemens, Safety is Essential for the New Normal
Mastering an Environment Characterized by ''VUCA''
Searching is a Thing of the Past
Social Distancing in Production and Logistics
Maximum Transparency in Electronics Production
Micro-Drive Systems Enhanced with GaN Power Semiconductors
Delivering Cars Ahead of Schedule
Virtual Round Table - Digitalization on the Rise: Siemens
Joint Solution for the Digitalization of Water Pumps
Applications for Machine-level Edge Computing
Partner Program Helps Choose the Right Product
Top-notch Products
Sure Signs of Excellence: Top Notch Products Offering Added Value
Room for new Perspectives. Simatic PCS 7 V9.0: More Flexibility in Process Automation
A Sure Sign of Excellence: Top-notch Products Offering Added Value
First-class Solutions for Industry
First-class Solutions for Industry
The Siemens Partner Program
Sure Sign of Excellence
Sure Signs of Excellence
The Siemens Partner Program
Quality Assurance in the Product Development and Production Process
Manage Wireless Networks from a Central Location with IWLAN Controller
Standard IE 4 Motors
Totally Integrated Automation
Proactive, Not Reactive!
Perfectly Organized
Automation Solution
Efficiency Through Single Source Technology
Easy Operation with all Fieldbuses and Controllers
Delivering Cars Ahead of Schedule
Real Time Energy Consumption Management
Higher Winding Quality on Non-Circular Bodies
The Siemens Partner Program
Powerful Identification Technology for Assembly Operations
Online Support Platform for Industrial Companies
Totally Integrated Automation
Standard IE 4 Motors
Automation Controllers with Integrated Safety
Related articles
Experience Hybrid Automation
Single-board Computer with 11th Gen Intel® Core™ U-series and Celeron® 6000 Processors
How Augmented Reality HMI Systems Improve Plant Management
Service Management Cloud Solution
AI computing, Network Capabilities and Miniature Design in IPCs
Automated Quality Control Solutions
No-code UniCloud specifically designed for Machine Builders
SPS 2021 - The Hybrid Exhibition Highlight
Cloud-based Solution for Service Management
Distributive IIoT Architecture
SPS Smart Production Solutions - November 23 to 25, 2021
MELFA ASSISTA Collaborative Robot from Mitsubishi Electric
Pepperl+Fuchs Series UC18GS Ultrasonic Sensor with IO-Link
JUMO variTRON 500 Central Processing Unit for an Automation System
When Automation Goes Digital
Unique IR Solutions
Achema 2021
Two/four-channel Process and Program Controller
Tailor-made Automation Solutions
Fastener Fair France
Ultra-rugged Computer-on-module for the Transportation Sector
Single Board Computer for Real-time Critical Applications
Global Survey Conducted by Molex Highlights Continued Progress in Industry 4.0
Semi-absolute Linear Encoder
JUMO variTRON 500 Central Processing Unit for an Automation System
Customized Membrane Switches for Demanding Applications
Versatile Industrial 5G Router
UniCloud – The Complete, No-Code, IIoT Cloud Platform for OEMs and Machine Builders by Unitronics
AC Servo Drives & Motors
Variable Frequency Drives
Cloud-based Solution for Service Management
Distributive IIoT Architecture
Ultra-rugged Computer-on-module for the Transportation Sector
Managed Service Suite Platform for Plant Asset Performance
Lilly Life Science Studio Automated Laboratory Goes Further in the Search For New Drugs
IERA 2021 Awarded to ABB's PixelPaint Solution
More Machining and Less Programming: ESPRIT Keeps the Success Flowing for WET
AC Servo Drives & Motors
Unistream®, the Award-Winning Programmable Controllers Series With Integrated HMI by Unitronics
Automated 3D Scanning and Inspection of Transport Stands