scholarly journals Trends in pneumatics – digitalization

2021 ◽  
Author(s):  
Herbert Hufnagl ◽  
Andrej Čebular ◽  
Marcus Stemler
Keyword(s):  
Flow Regulation ◽  
Torque Control ◽  
System Level ◽  
Leakage Detection ◽  
Control Logic ◽  
Valve Unit ◽  
Running System ◽  
Unit Design ◽  
Cloud User ◽  
Technology Trends

The paper presents an overview of the latest technology trends in pneumatic automatization at Festo, focusing on digitalization from a component to a system level. The Festo Motion Terminal (VTEM) is valve terminal, designed for digitalization. Unique valve unit design allows valve functions to be defined by a software and to be changed in a running system very quickly, even on the fly. Model based applications on a valve controller offer many advanced functionalities such as: pneumatic servo positioning, force and torque control of pneumatic drives and pressure or flow regulation in pneumatic systems. VTEM native connectivity with higher order controllers adds a possibility to seamlessly integrate it on all levels, from the field to the cloud. User control logic and/or AI algorithms in a combination with digitalized pneumatics allows new services, such as: auto-commissioning, predictive maintenance, increased energy efficiency, automatic leakage detection within pneumatic systems and many others.

scholarly journals A Control Scheme with the Variable-Speed Pitch System for Wind Turbines during a Zero-Voltage Ride Through

Energies ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 3344
Author(s):  
Enyu Cai ◽  
Yunqiang Yan ◽  
Lei Dong ◽  
Xiaozhong Liao
Keyword(s):  
Wind Turbines ◽  
Low Voltage ◽  
System Modeling ◽  
Fault Analysis ◽  
System Level ◽  
Level Control ◽  
Control Logic ◽  
Control Scheme ◽  
Pitch System ◽  
Zero Voltage

Zero-voltage ride through (ZVRT) is the extreme case of low-voltage ride through (LVRT), which represents the optimal grid-connection capability of wind turbines (WTs). Enforcing ZVRT will improve the dynamic performance of WTs and therefore significantly enhance the resiliency of renewable-rich grids. A control scheme that includes a pitch system is an essential control aspect of WTs riding through voltage dips; however, the existing control scheme with a pitch system for LVRT cannot distinguish between a ZVRT status and a power-loss condition, and, consequently, does not meet the ZVRT requirements. A system-level control scheme with a pitch system for ZVRT that includes pitch system modeling, control logic, control circuits, and overspeed protection control (OPC) is proposed in this paper for the first time in ZVRT research. Additionally, the field data are shared, a fault analysis of an overspeed accident caused by a voltage dip that describes the operating status at the WT-collapse moment is presented, and some existing WT design flaws are revealed and corrected by the fault analysis. Finally, the pitching performance during a ZVRT, which significantly affects the ZVRT performance of the WT, is obtained from laboratory and field tests. The results validate the effectiveness of the proposed holistic control scheme.

Skylab's Astronaut Maneuvering Unit (Experiment M509) — A Comparison of Six Degree of Freedom Simulation and on-Orbit Flight

1974 ◽  
Vol 18 (2) ◽  
pp. 187-187
Author(s):  
A. M. Ray
Keyword(s):  
Space Shuttle ◽  
Space Station ◽  
Degree Of Freedom ◽  
Test Bed ◽  
Control Logic ◽  
Test And Evaluation ◽  
Unit Design ◽  
Design Requirements ◽  
Experiment Hardware ◽  
Six Degree Of Freedom

A test bed type astronaut maneuvering unit was designed and evaluated with the assistance of Martin Marietta's six degree of freedom simulator. Four different control modes were developed for this unit for test and evaluation inside Skylab's 22 foot diameter orbital workshop. The orbital tests have provided the experience and technology base necessary for space Shuttle and space station astronaut maneuvering unit design requirements. This paper is an overview of the M509 experiment hardware, procedures, and results with emphasis on the comparison between on-orbit test results and the six degree of freedom simulator. The simulator was used to develop the unit's design requirements, evaluate the control logic parameters, and for developing maneuvers and training the crew. The simulator will also be flown by the Skylab crews in May for post flight evaluation and simulator calibration. (Films of the simulations and on-orbit flight are available as part of this presentation.)

scholarly journals Simulation Research on Auxiliary Power Supply System of China Standard EMU

Electronics ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 647 ◽  
Author(s):  
Liwei Zhang ◽  
Lansi Yun ◽  
Minghe Sun ◽  
Bo Peng
Keyword(s):  
Power Supply ◽  
Power Supply System ◽  
Supply System ◽  
Operating Conditions ◽  
System Level ◽  
Constant Current ◽  
Experimental Comparison ◽  
Control Logic ◽  
System Level Simulation ◽  
Auxiliary Power

The auxiliary power supply system is an important part of the China standard EMU (Electric Multiple Units). It is mainly composed of auxiliary converters, chargers, battery packs and several loads. According to the topology of the EMU real auxiliary power supply system, the whole simulation system including the auxiliary converter, charger, single-phase inverter and other single models is built, and the internal working principle and working process of the system are studied. The auxiliary converter adopts the droop control method introducing virtual impedance to reduce the circulation effect of the parallel system. Combined with the battery pack charging characteristic curve, the constant current and constant voltage step-by-step charging management strategy is studied. The actual operating conditions of the system are simulated according to the auxiliary power supply system control logic. The system-level simulation on the MATLAB/Simulink platform shows that the output performance of each component is good, working in the rated parameters and meeting the working requirements of the auxiliary power supply system. Finally, the rationality, stability and robustness of the auxiliary power supply system model are proved by simulation and experimental comparison. This research provides a certain theoretical basis for the research of China standard EMU auxiliary power supply system, which has a certain significance.

scholarly journals Nhận dạng động cơ không đồng bộ sáu pha sử dụng mạng neuron RBF

2021 ◽  
Vol 57 (4) ◽  
pp. 18-29
Author(s):  
Việt Trung Nguyễn ◽  
Pham Thanh Tung
Keyword(s):  
Radial Basis Function ◽  
Basis Function ◽  
Direct Torque Control ◽  
Torque Control ◽  
Field Oriented Control ◽  
Control Logic ◽  
Matlab Simulink ◽  
Radial Basis

Nhận dạng hệ thống là một trong những công việc đầu tiên phải thực hiện khi giải quyết bài toán điều khiển tự động bởi vì không thể phân tích, tổng hợp hệ thống khi không có mô hình toán mô tả hệ thống. Bài báo này trình bày và mô phỏng phương pháp nhận dạng động cơ không đồng bộ sáu pha sử dụng mạng neuron hàm cơ sở xuyên tâm (RBF – Radial Basis Function), thông số nhận dạng gồm có tốc độ quay, mômen xoắn, từ thông rotor trên hệ trục cố định . Mạng RBF được xây dựng, huấn luyện trực tuyến dựa trên dữ liệu vào ra của đối tượng. Kết quả mô phỏng dùng phần mềm Matlab/Simulink cho thấy sai số của bộ nhận dạng hội tụ về 0. Thông số nhận dạng bám theo thông số đối tượng trong khoảng thời gian động cơ khởi động, sau khi lắp tải và có nhiễu trắng tác động, độ phù hợp giữa đáp ứng ngõ ra và đáp ứng nhận dạng nằm trong khoảng 98%-99%. Nghiên cứu này là tiền đề để tiến đến các phương pháp điều khiển hiệu suất cao như điều khiển trực tiếp mômen (DTC – Direct Torque Control), điều khiển tựa từ thông (FOC – Field Oriented Control), Logic mờ được thuận lợi hơn.

scholarly journals Design and Implementation of Enterprise the Reimbursement Management System Based on SSH Architecture

2013 ◽  
Vol 347-350 ◽  
pp. 2261-2265
Author(s):  
Gui Jun Liu ◽  
Chun Shan Yang
Keyword(s):  
Management System ◽  
System Level ◽  
Business Logic ◽  
Control Logic ◽  
Mvc Pattern ◽  
Design And Implementation ◽  
S Model ◽  
And Control ◽  
Degree Of Coupling ◽  
Claims Management

t is based on c/s and b/s mode for traditional enterprise claims management system, system level architecture is unclear, invasive, and reusability lower defects, and increases the workload and complexity of management. In view of this, uses the MVC pattern and the SSH technology, build tiered architecture, Enterprise claims management system the separation of business logic and control logic, on the basis of design and implementation based on B/S model of enterprise claims management system. Practical application shows that enterprise claims management system framework based on SSH hierarchy clear, reduce the degree of coupling between modules, improved granularity of reuse, enhanced system modules can be reused, flexibility, and maintainability

Where do we stand? Comparing system-level service lines in the private sector and in VHA

1998 ◽  
Author(s):  
Martin P. Charns ◽  
Victoria A. Parker ◽  
William H. Wubbenhorst
Keyword(s):  
Private Sector ◽  
System Level
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