scholarly journals Application of D-Decomposition Technique to Selection of Controller Parameters for a Two-Mass Drive System

Energies ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 6614
Author(s):  
Radosław Nalepa ◽  
Karol Najdek ◽  
Karol Wróbel ◽  
Krzysztof Szabat
Keyword(s):  
Analytical Formula ◽  
Drive System ◽  
Decomposition Technique ◽  
Motor Speed ◽  
Control Structures ◽  
Drive Systems ◽  
The Impact ◽  
The Mathematical Model ◽  
Theoretical Considerations ◽  
Selection Of

In this work, issues related to the application of the D-decomposition technique to selection of the controller parameters for a drive system with flexibility are presented. In the introduction the commonly used control structures dedicated to two-mass drive systems are described. Then the mathematical model as well as control structure are introduced. The considered structure has only basic feedbacks from the motor speed and PI type controller. Due to the order of the closed-loop system, the free location of the system’s poles is not possible. Large oscillations can be expected in responses of the plant. In order to improve the characteristics of the drive, the tuning methodology based on the D-decomposition technique is proposed. The initial working point is selected using an analytical formula. Then the value of controller proportional gain is decreasing, until the required value of overshoot is obtained. In the paper different advantages of the D-decomposition technique are presented, for instance calculation of global stability area for the selected gain and phase margin, the impact of parameter changes, and additional delay evident in the system. Theoretical considerations are confirmed by simulation and experimental results.

scholarly journals Effect of Gate Selection on the Non-Cohesive Sedimentation in Irrigation Schemes

Water ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2765
Author(s):  
Shaimaa Theol ◽  
Bert Jagers ◽  
Jigyasha Rai Yangkhurung ◽  
F.X. Suryadi ◽  
Charlotte de Fraiture
Keyword(s):  
Cohesive Sediment ◽  
Sediment Deposition ◽  
Hydraulic Parameters ◽  
Crop Water ◽  
Gate Operation ◽  
Control Structures ◽  
Sediment Removal ◽  
1D Model ◽  
The Impact ◽  
Selection Of

In order to cover the crop water requirements, flow control structures such as gates and weirs are used to transfer the desired amount of water from the canals to the field canals. This paper examines the impact of gate operation and the selection of gates on the deposition of non-cohesive sediment. The Delft3D model is used to simulate the effects of different scenarios regarding gate operation and the location of the gate that is opened. The model results showed that the gate selection affects not only hydraulic parameters but also morphological parameters. It was found that opening the gates closer to the offtake resulted in less sediment deposition at the entrance of the branch canal when compared to opening the gates further away. Gate selection can be used as a tool in sediment management. By alternating the opening of different gates sediments that are already deposited after opening one gate can be eroded when another gate is operated, thus minimizing the additional cost of sediment removal. The use of Delft3D proved beneficial as the selection of different gates leads to asymmetric sediment deposition patterns which would be missed when using a 1D model.

scholarly journals Losses and energy efficiency of drive motors and systems

2013 ◽  
Vol 20 (1) ◽  
pp. 3-10 ◽  
Author(s):  
Zygmunt Paszota
Keyword(s):  
Energy Efficiency ◽  
Power Flow ◽  
Objective Evaluation ◽  
Drive System ◽  
Motor Speed ◽  
Rotational Displacement ◽  
Operating Field ◽  
Useful Power ◽  
New Perspective ◽  
Drive Systems

Abstract Losses and energy efficiency of every drive motor must be presented as functions of physical quantities independent of losses in the motor. Such quantities are speed and load required by the machine or device driven by the motor, changing in the drive operating field. Speed and load of the motor decide of the instantaneous useful power of the motor and also in a differentiated way of kinds and values of losses occurring in the motor. However, losses and energy efficiency of the hydrostatic drive motors and systems are evaluated by researchers and manufacturers as functions of parameters depending on the losses. The basic cause of such situation is the traditional, commonly accepted but erroneous, view of the power flow in the drive motors and systems represented by the Sankey diagram of power decrease in the direction of power flow. It is necessary to replace the Sankey diagram by the proposed diagram of increase of power in the motor and in the drive system in the direction opposite to the direction of power flow. The proposed view of losses and energy efficiency should be applied to all types of motor and drive systems. The aim of this paper is showing the resulting problems of the above postulates, exemplified by operation of a rotational displacement motor in a hydrostatic drive system. In order to make possible objective evaluation of the energy behaviour of different motor and system solutions and sizes, the losses and energy efficiency should be described and compared as dependent on the motor speed coefficient ωM and load coefficient M changing in the drive system operating field (0 ≤ ωM< ωMmax, 0 ≤ M< Mmax). The presented proposals open a new perspective of unavoidable research of drive motors and systems, making it possible to compare objectively the energy efficiency of different types of motors and drive systems.

scholarly journals Multi-Inverter Linear Motor Based Vehicle Propulsion System for a Small Cargo Transportation

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4459
Author(s):  
Marek Michalczuk ◽  
Marcin Nikoniuk ◽  
Paweł Radziszewski
Keyword(s):  
Transportation System ◽  
Linear Motor ◽  
Transportation Systems ◽  
Drive System ◽  
Vehicle Propulsion ◽  
Multi Level ◽  
Drive Systems ◽  
The Impact ◽  
System Power ◽  
System Characteristics

The paper provides an analysis of a transportation system with a long stator linear drive. The presented analysis for an in-house transportation system may be easily scaled into large transportation systems like maglev and hyperloop. It investigates the impact of the division of the stator into shorter parts which are sequentially supplied. Then it compares the concept of single-inverter and multi-inverter drive systems. The presented research includes the analysis of drive system power parameters. The drive system characteristics depending on the length of the active part of the linear motor are presented for each configuration, followed by a description of differences in the required inverter power and the obtained average thrust force. The paper proposes a new arrangement of the multi-inverter drive system incorporating multi-level inverters, which allows decreasing voltage oscillations in the DC circuit of drive inverters. The operation of the transportation system is presented in a simulation study. The paper is concluded with the verification of the concept in an experimental study in a 50 m test track.

scholarly journals Determination of Coefficients of Energy Losses Occurring in a Constant Capacity Pump Working in a Typical Hydrostatic Drive

2019 ◽  
Vol 26 (1) ◽  
pp. 159-166
Author(s):  
Grzegorz Skorek
Keyword(s):  
Energy Efficiency ◽  
Drive System ◽  
Energy Losses ◽  
Motor Speed ◽  
Hydraulic Motor ◽  
Viscosity Change ◽  
Building Models ◽  
Nominal Pressure ◽  
Low Efficiency ◽  
Drive Systems

Abstract In order to assess possibilities of energy saving during hydrostatic drive system operation, should be learned, and described losses occurring in system. Awareness of proportion of energy, volume, pressure, and mechanical losses in elements is essential for improving functionality and quality of hydrostatic drive systems characterized by unquestionable advantages. In systems with too low efficiency there is increase of load, mainly in case of pump load, which can lead to higher risk of failure, necessity of repair or replacement, as well as to shorten service life of system. Coefficients ki, given in subject literature by Paszota, describe relative value of individual losses in element. They make it possible to assess proportions of losses and assess value of energy efficiency (volumetric, pressure, mechanical) resulting from losses occurring at nominal pressure pn of system in which element is used. As a result, thanks to knowledge of coefficients ki of individual losses, it is possible to determine losses and energy efficiency of components operating in hydraulic system as well as efficiency of system with defined structure of motor speed control as function of speed and load coefficient of motor. Knowledge of coefficients of energy losses occurring in system elements (pump, hydraulic motor, conduits, and motor) allows building models of losses and energy efficiency of element working in system and energy efficiency of system as whole composed of elements. Mathematical models of losses and energy efficiency in system must take into account conditions resulting from applied structure of system, from level of nominal pressure, from rotational speed of motor driving pump shaft, from viscosity change of applied hydraulic oil. Article presents method of determining coefficients of axial piston pump used in typical hydrostatic drive system with proportional control. Values that can be assumed for these loss coefficients for other hydraulic pumps are also given.

scholarly journals Resonant Suppression Method Based on PI control for Serial Manipulator Servo Drive System

2020 ◽  
Vol 103 (3) ◽  
pp. 003685042095013
Author(s):  
Xiaopeng Li ◽  
Dongyang Shang ◽  
Haiyang Li ◽  
Fanjie Li
Keyword(s):  
Dynamic Characteristics ◽  
Pi Controller ◽  
Drive System ◽  
Pi Control ◽  
Motor Speed ◽  
Servo Drive ◽  
Serial Manipulators ◽  
Drive Systems ◽  
Servo Drive System ◽  
Serial Mechanism

A typical serial manipulator consists of a servo motor, a serial mechanism and an independent joint placed between the motor and the serial mechanism. Both the time-varying characteristics of the inertia of the serial mechanism and the flexibility characteristics of the independent joint are widely found in serial manipulator servo drive systems. These two characteristics not only increase the resonance magnitude of serial manipulators, but also affect the dynamic characteristics of the system. In order to obtain a stable output speed of serial manipulators, the variable parameters of a PI control strategy is applied to a serial manipulator servo drive system. Firstly, dynamic model of a serial manipulator servo drive system is established based on a two-inertia system. Then the transfer function from motor speed to motor electromagnetic torque is derived by the state-space equation. Furthermore, the parameters of the PI controller are designed and optimized utilizing three different pole assignment strategies with the identical radius, the identical damping coefficients, and the identical real parts. The results indicate that a serial manipulator servo drive system can obtain good dynamic characteristics by selecting parameters of the PI controller appropriately.

scholarly journals Measuring Instruments Used at the Research and Accuracy of Defining the Efficiency of Drive Systems

2019 ◽  
Vol 26 (2) ◽  
pp. 129-135
Author(s):  
Grzegorz Skorek
Keyword(s):  
Energy Efficiency ◽  
Test Stand ◽  
Energy Losses ◽  
Measuring Instruments ◽  
Motor Speed ◽  
Hydraulic Motor ◽  
Accuracy Of Measurements ◽  
Drive Systems ◽  
The Mathematical Model

Abstract The aim of the article is to look at the possibility of accurately determining the energy efficiency of drive systems thanks to the use of high quality sensors and measuring instruments. The types of measuring instruments used on the test stand are presented. The results of experimentally determined efficiencies and simulationally determined efficiencies of two hydrostatic systems with throttling control were compared, which are fed with a constant capacity pump. The choice of the analysed systems is not accidental. There is still a view in the literature about limited possibilities of energy systems with proportional control. The research stand was very carefully designed and made. The applied measuring instruments were characterized by high accuracy of measurements. The issues related to the determination of energy losses and energy efficiency of the engine or drive system, which should be determined as dependent on the physical quantities independent of these losses, were also discussed. For laboratory verification, measurement methods were developed, the test stand was adapted and automated. It consists of tested system and loaded system. The measurements during the tests were saved on the computer disk. In order to be able to compare the efficiency of the overall system with the efficiency obtained on the basis of the simulation, coefficients ki determining the energy losses of individual elements of the system were calculated. The research showed a large convergence of the mathematical description of energy losses in the elements of the system and the efficiency of the system with reality. The mathematical model enables accurate simulation determination of the energy efficiency of the system at each point of its field of operation, i.e. at each speed and load of the controlled hydraulic motor. The range of motor speed and load variation can also be accurately determined simulationally.

Methods for Restricting Maximum Exposure Rate in Computerized Adaptative Testing

Methodology ◽  
2007 ◽  
Vol 3 (1) ◽  
pp. 14-23 ◽  
Author(s):  
Juan Ramon Barrada ◽  
Julio Olea ◽  
Vicente Ponsoda
Keyword(s):  
Measurement Accuracy ◽  
Computerized Adaptive Testing ◽  
Computation Time ◽  
Adaptive Testing ◽  
Exposure Rate ◽  
Control Parameters ◽  
The Impact ◽  
Two Alternatives ◽  
Selection Of ◽  
Maximum Exposure

Abstract. The Sympson-Hetter (1985) method provides a means of controlling maximum exposure rate of items in Computerized Adaptive Testing. Through a series of simulations, control parameters are set that mark the probability of administration of an item on being selected. This method presents two main problems: it requires a long computation time for calculating the parameters and the maximum exposure rate is slightly above the fixed limit. Van der Linden (2003) presented two alternatives which appear to solve both of the problems. The impact of these methods in the measurement accuracy has not been tested yet. We show how these methods over-restrict the exposure of some highly discriminating items and, thus, the accuracy is decreased. It also shown that, when the desired maximum exposure rate is near the minimum possible value, these methods offer an empirical maximum exposure rate clearly above the goal. A new method, based on the initial estimation of the probability of administration and the probability of selection of the items with the restricted method ( Revuelta & Ponsoda, 1998 ), is presented in this paper. It can be used with the Sympson-Hetter method and with the two van der Linden's methods. This option, when used with Sympson-Hetter, speeds the convergence of the control parameters without decreasing the accuracy.

AGENT'S REPUTATION, ACCOUNTING AND COSTING IN ORGANISATIONAL CONTROL STRUCTURES

1997 ◽  
Vol 24 (1) ◽  
pp. 1-23 ◽  
Author(s):  
Tom McLean
Keyword(s):  
Coal Mining ◽  
Industrial Revolution ◽  
Control Structures ◽  
The Impact

This paper examines the roles of accounting and costing in the management of coal mining during the Industrial Revolution in Britain, and considers the impact of the agent's reputation in the development and use of these systems.

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