Higher process precision in machinery construction Self-learning compensation to achieve the highest degree of performance siemens.com/machinebuilding
Smart fault avoidance through learning and compensating Product quality has highest priority in machine construction. To achieve this, a precise and fault-free process is absolutely mandatory. However, disturbances as a result of the mechanical situation in the process itself are very difficult to avoid. Higher process quality for higher product quality Even if individual machinery construction sectors differ from one another significantly, they often have similar issues. For instance, in the widest range of applications, process axes suddenly develop a position error as a result of mechanical impact triggered by motion of the mechanical system, a product or material being transported or the machining of a workpiece. Together with the standardized PROFIdrive profile, the open controller structure of SIMOTION and SINAMICS provides the optimum basis for efficient compensation. Based on the following error, the algorithm calculates the value to be precontrolled, which it then injects into the closed-loop control in the next cycle. The following diagram clearly shows the precise principle of operation: Cylinder rotation (gray, 0 360 ) Drive control error before (red) and after (green) injection of the compensation signal Learned precontrol value (blue) A dynamic position controller is always required in order to guarantee a high process quality. However, this can only respond with some delay. Here, Siemens offers a smart alternative for cyclic processes: LECo (Learning Error Compensation), the self-learning application for the SIMOTION motion control system. Automatic adaptation with every cycle LECo monitors the following error of the axis object, identifies deviations and corrects these. After just one cycle, the deviation or error is compensated to a large extent and fine tuning in the subsequent cycle results in optimum process results. Setpoints and control deviations are related to the process, and therefore directly to the load. The fast closedloop position control running in the current controller clock cycle of the SINAMICS S120 drive effectively suppresses disturbances. SIMOTION LECo SINAMICS S120 After one revolution of the cylinder, the drive control error has been learned and is then immediately used for compensation. The learned algorithm then continually monitors the compensation result. It can be clearly seen that only the component of the drive control error associated with the disturbance cycle is compensated. Other disturbances that are not periodic or have a different periodicity are minimized by the active closed-loop control. GEAR 0 to 360 s t Xerr DSC POS Ctrl Velocity Ctrl M 2
Self-learning compensation using Flexo printing as an example Streaking problems are a known issue when it comes to Flexo printing. Possible causes include drive control errors, caused by the unevenness of the Flexo printing plate. The combination of SIMOTION motion control system, SINAMICS S120 drives and the intelligent LECo control algorithm represent the ideal solution so that this repetitive disturbance can be automatically learned by the system and precontrolled so that it can be limited to a minimum. High-performance open-loop control and open structure The load torque continually changes as a result of the arrangement of the cylinder and the unevenness of the printing plate. For Flexo printing, this depends on the image that is being printed, the speed, contact pressure and other associated factors. The load torque represents a disturbing variable for the printing plate cylinder drive and results in drive control errors, which are emulated in the printed image and periodically repeated with the print format. The LECo application learns and compensates the cyclic errors therefore increasing the quality. The self-learning behavior facilitates automatic adaptation even for new conditions after a format change. siemens.com/printing Typical cylinder arrangement of a Flexo printing unit: Anilox (left), plate cylinder (center), impression cylinder (right)
Self-learning compensation using test stand technology as an example Frequently, when it comes to test stands, a constant torque with no ripple is demanded. External torque disturbances can be generated in the mechanical system, as a result of the motor or the test object itself. These disturbances have a negative impact on the measurement results of the test stand, and can even mean that the results cannot be used. Understand the disturbance and precontrol For instance, LECo is used at the end-of-line test for large combustion engines. These tests also known as a cold tests are carried out in state-of-the-art production environments as a quality test, directly integrated in the assembly line. Contrary to hot testing, with cold testing, the engine is not actually fired up, but driven electrically and therefore tested in an environmentally-friendly fashion. Checking the compression (cylinder head) and that the engine operates smoothly and uniformly (pistons) indicates whether the engine complies with the quality specifications. When driving the internal combustion engine on a test stand, periodic torque surges occur as a result of the compression cycles. LECo compensates these and creates a constant speed, which indicates that a motor has been produced to specifications. Faults are identified as a result of non-periodic disturbing torques that result in a speed deviation. When TEC LECo is activated, typically between four and six periodic disturbances are adequate to achieve optimum compensation. In tests, results representing ideal smooth running operation are achieved down to 0.0001. Advantages: Only a few parameter settings are required Engines that are not up to specification are clearly identified New engines are quickly learned Independent of ETP (engine torque pulsations) No external measuring technology is required Electric Elektromotor Kupplung Coupling Internal Verbrennungsmotor combustion engine siemens.com/testing-equipment
SINAMICS S120 and SIMOTION a perfect team SINAMICS S120 the dynamic drive system The modular SINAMICS S120 drive system is the basis for high-performance applications in industrial machinery and plant construction. A wide range of components and functions that are harmonized and coordinated with one another for example powerful individual drives and coordinated drives (multi-axis applications) with vector or servo functionality facilitate customized solutions. The SIMOTICS range of motors is perfectly harmonized to operate with SINAMICS S120. SIMOTION the scalable motion control system SIMOTION is the first choice wherever motion plays a role. Every machine can be reliably and efficiently controlled with a high degree of performance using the scalable, modular motion control system. SIMOTION is optimally suited to address distributed machine concepts and sets itself apart as a result of the user-friendly engineering, fast commissioning and the highest degree of flexibility. The design admirably supports modular machine concepts and simplifies the implementation of different machine versions. Here, the SIMOTION software covers all functions, and together with PROFINET provides the interface for the modules to communicate with one another. 5
Find out more: siemens.com/ids Discover in detail how Integrated Drive Systems boost your competitive edge and improve your time to profit. Integrated Drive Systems to go: Visit our mobile site! Follow us on: www.twitter.com/siemensindustry www.youtube.com/siemens Published by Siemens AG 2016 Digital Factory P.O. Box 31 80 91050 Erlangen, Deutschland Article No.: E20001-A450-P670-X-7600 Printed in Germany Dispo 21500 GuBe/80372 SB 05162.0 Subject to changes and errors. The information given in this document only contains general descriptions and/or performance features which may not always specifically reflect those described, or which may undergo modification in the course of further development of the products. The requested performance features are binding only when they are expressly agreed upon in the concluded contract. For the secure operation of Siemens products and solutions, it is necessary to take suitable preventive action (e.g. cell protection concept) and integrate each component into a holistic, stateof-the-art industrial security concept. Third-party products that may be in use should also be considered. For more information about industrial security, visit http://www.siemens.com/ industrialsecurity