Adaptive Control of Rotor Vibration Using Compact Wavelets

This paper investigates the use of dyadic wavelets for the control of multifrequency rotor vibration. A scheme for real-time control of rotor vibration using an adaptive wavelet decomposition and reconstruction of time-varying signals is proposed. Quasi-periodic control forces are constructed adaptively in real-time to optimally cancel vibration produced by nonsmooth disturbance forces. Controller adaptive gains can be derived using a model-based synthesis or from system identification routines. The controller is implemented on a flexible rotor system incorporating two radial magnetic bearings, with standard proportional-integral-derivative control employed in a parallel feedback loop for rotor levitation. An experimental investigation of controller performance is used to deduce the best choice of wavelet basis for various operating conditions. These include steady synchronous forcing, step changes in synchronous forcing and multifrequency forcing produced by a rotor impact mechanism.

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Transfer Function Modelling of Urban Drainage Systems, and Potential Uses in Real-Time Control Applications

Water Science & Technology ◽

10.2166/wst.1994.0689 ◽

1994 ◽

Vol 29 (1-2) ◽

pp. 409-417 ◽

Cited By ~ 5

Author(s):

Andrea G. Capodaglio

Keyword(s):

Transfer Function ◽

Real Time ◽

Sewage Treatment ◽

Operating Conditions ◽

Urban Drainage ◽

Real Time Control ◽

Control Applications ◽

Time Control ◽

Function Modelling ◽

Transfer Function Modelling

According to the present state-of-the-art, sewerage systems, sewage treatment plants and their subsequent improvements are often planned and designed as totally separate entities, each subject to a specific set of performance objectives. As a result, sewage treatment efficiency is subject to considerable variability, depending both on general hydrologic conditions in the urban watershed (wet versus dry periods), and on specific “instantaneous” operating conditions. It has been postulated that the integration of urban drainage and wastewater treatment design and operation could allow minimization of the harmful effects of discharges from treatment plants, overflows and surface water runoff. This “ideal condition” can be achieved through the introduction of so-called “real-time control” technology in sewerage collection and treatment operations. To be a feasible goal, this technology poses the demand for more powerful simulation models of either aspect of the system - or, ideally, of a unified sewer-and-treatment plant model - than most of those currently available. This paper examines the requirements of rainfall/runoff transformation and sewer flow models with respect to real-time control applications, and focuses on the methodology of stochastic, transfer function modelling, reporting application examples. Modalities and limitations of the extraction of information from the models thus derived are also analyzed.

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Design of Real-Time Control Based on DP and ECMS for PHEVs

Mathematical Problems in Engineering ◽

10.1155/2021/6667614 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Wei Wang ◽

Zhenjiang Cai ◽

Shaofei Liu

Keyword(s):

Real Time ◽

Fuel Consumption ◽

Mode Selection ◽

Time Algorithm ◽

Operating Conditions ◽

Real Time Control ◽

Time Control ◽

Manual Adjustment ◽

Equivalent Fuel ◽

Equivalent Fuel Consumption

A real-time control is proposed for plug-in-hybrid electric vehicles (PHEVs) based on dynamic programming (DP) and equivalent fuel consumption minimization strategy (ECMS) in this study. Firstly, the resulting controls of mode selection and series mode are stored in tables through offline simulation of DP, and the parallel HEV mode uses ECMS-based real-time algorithm to reduce the application of maps and avoid manual adjustment of parameters. Secondly, the feedback energy management system (FMES) is built based on feedback from SoC, which takes into account the charge and discharge reaction (CDR) of the battery, and in order to make full use of the energy stored in the battery, the reference SoC is introduced. Finally, a comparative simulation on the proposed real-time controller is conducted against DP, the results show that the controller has a good performance, and the fuel consumption value of the real-time controller is close to the value using DP. The engine operating conditions are concentrated in the low fuel consumption area of the engine, and when the driving distance is known, the SoC can follow the reference SoC well to make full use of the energy stored in the battery.

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INTEGRAL CONTROL REQUIREMENTS FOR SEWERAGE SYSTEMS

Water Science & Technology ◽

10.2166/wst.1994.0014 ◽

1994 ◽

Vol 30 (1) ◽

pp. 131-138

Author(s):

Andrea G. Capodaglio

Keyword(s):

Real Time ◽

Sewage Treatment ◽

Operating Conditions ◽

Ideal Condition ◽

Real Time Control ◽

Combined Sewer Overflows ◽

Integral Control ◽

Time Control ◽

Combined Sewer ◽

Harmful Effects

Sewerage systems and sewage treatment plants are often planned, designed and operated as totally separate entities. As a result, sewage treatment efficiency is subject to considerable variability, depending both on general hydrologic conditions in the urban watershed (wet versus dry periods), and on specific “instantaneous” operating conditions. It has been postulated that the integration of design and operation in urban drainage and wastewater treatment could allow minimization of the harmful effects of discharges from treatment plants, combined sewer overflows and surface runoff. This “ideal condition” can be achieved through the introduction of so-called “Real-Time Control” technology in sewerage collection and treatment operations. This paper examines the requirements of a hypothetical integrated sewer flow and sewage treatment model, the mathematical tools used to design and operate Real-Time Control systems, and the issues emerging from an integration of the conveyance and disposal aspects of the sewerage cycle.

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A real-time control strategy for separation of highly polluted storm water based on UV–Vis online measurements – from theory to operation

Water Science & Technology ◽

10.2166/wst.2011.164 ◽

2011 ◽

Vol 63 (10) ◽

pp. 2287-2293 ◽

Cited By ~ 13

Author(s):

H. Hoppe ◽

S. Messmann ◽

A. Giga ◽

H. Gruening

Keyword(s):

Real Time ◽

Stream Water ◽

Treatment Plant ◽

Operating Conditions ◽

Storm Water ◽

Water Runoff ◽

Real Time Control ◽

Flow Measurements ◽

Time Control ◽

Storm Water Runoff

‘Classical’ real-time control (RTC) strategies in sewer systems are based on water level and flow measurements with the goal of activation of retention volume. The control system rule of ‘clean (storm water) runoff into the receiving water – polluted runoff into the treatment plant’ has been thwarted by rough operating conditions and lack of measurements. Due to the specific boundary conditions in the city of Wuppertal's separate sewer system (clean stream water is mixed with polluted storm water runoff) a more sophisticated – pollution-based – approach was needed. In addition the requirements to be met by the treatment of storm water runoff have become more stringent in recent years. To separate the highly-polluted storm water runoff during rain events from the cleaner stream flow a pollution-based real-time control (P-RTC) system was developed and installed. This paper describes the measurement and P-RTC equipment, the definition of total suspended solids as the pollution-indicating parameter, the serviceability of the system, and also gives a cost assessment. A sensitivity analysis and pollution load calculations have been carried out in order to improve the P-RTC algorithm. An examination of actual measurements clearly shows the ecological and economic advantages of the P-RTC strategy.

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A Real Time Control Architecture for Continuously Managing Patients in a Care Unit

Methods of Information in Medicine ◽

10.1055/s-0038-1634619 ◽

1995 ◽

Vol 34 (05) ◽

pp. 475-488

Author(s):

B. Seroussi ◽

J. F. Boisvieux ◽

V. Morice

Keyword(s):

Real Time ◽

Linear Time ◽

Treatment Plan ◽

Control Architecture ◽

Real Time Control ◽

Time Representation ◽

Time Control ◽

Continuous Support ◽

Definition Of ◽

Computerized System

Abstract:The monitoring and treatment of patients in a care unit is a complex task in which even the most experienced clinicians can make errors. A hemato-oncology department in which patients undergo chemotherapy asked for a computerized system able to provide intelligent and continuous support in this task. One issue in building such a system is the definition of a control architecture able to manage, in real time, a treatment plan containing prescriptions and protocols in which temporal constraints are expressed in various ways, that is, which supervises the treatment, including controlling the timely execution of prescriptions and suggesting modifications to the plan according to the patient’s evolving condition. The system to solve these issues, called SEPIA, has to manage the dynamic, processes involved in patient care. Its role is to generate, in real time, commands for the patient’s care (execution of tests, administration of drugs) from a plan, and to monitor the patient’s state so that it may propose actions updating the plan. The necessity of an explicit time representation is shown. We propose using a linear time structure towards the past, with precise and absolute dates, open towards the future, and with imprecise and relative dates. Temporal relative scales are introduced to facilitate knowledge representation and access.

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