Understanding milling tandem control

Sugar Industry ◽

10.36961/si24553 ◽

2020 ◽

pp. 422-426

Author(s):

Geoffrey A. Kent

Keyword(s):

Rate Control ◽

Capacity Constraints ◽

Torque Control ◽

Rate Performance ◽

Constant Ratio ◽

Level Control ◽

Added Water ◽

Water Rate ◽

Considerable Work ◽

Mill Speed

Considerable work has been done over the years to automatically control the operation of the milling tandem. Control can be achieved by utilising relatively simple algorithms. Chute-level control, added-water rate control and speed and torque control of each mill drive are the main elements of the control system. Factory rate control can be achieved by controlling the prepared cane level in the chute of the first mill and controlling the first-mill speed to a set point that may vary depending on factory capacity constraints. Added water rate should vary with the objective of maintaining a relatively constant ratio to the cane-fibre rate, with a potential advantage to extraction by increasing further when pol in cane is high. For rate, performance and protection, the speed of and torque on each milling unit drive should be controlled.

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Proper Orthogonal Decomposition Analysis and Braking Control on Hydrodynamic Retarders by Bionic Iris Effective Diameter Regulation

10.1115/gt2021-60208 ◽

2021 ◽

Author(s):

Xiuqi Chen ◽

Wei Wei ◽

Tangzhu Liu ◽

Wenhao Xie ◽

Yifei Li ◽

...

Keyword(s):

Flow Field ◽

Rate Control ◽

Decomposition Analysis ◽

Middle Layer ◽

Torque Control ◽

Effective Diameter ◽

Circular Membrane ◽

Nonlinear Controller ◽

Filling Rate ◽

Braking Torque

Abstract AIris, a flat circular membrane in the middle layer of human eyeball, is controlled by sympathetic nerve and can automatically adjust pupil size according to light intensity to limit the amount of light entering the eyeball. This paper attempts to introduce the artificial iris diameter changing mechanism into hydrodynamic machinery, that is, to control the hydrodynamic retarder without filling fluid by changing the inner diameter of iris and changing the flow path of retarder. Through the decomposition and reconstruction of the intrinsic flow field, the flow field characteristics of the iris retarder are deeply understood, and the fast prediction of the braking torque is realized. At the same time, the close-loop controller is designed to control the iris opening that realizing the adaptive adjustment of the output torque of the retarder, thus overcoming the difficulty on-line observation of actual filling rate of oil problem and the inaccurate tracking of braking torque on traditional hydrodynamic retarder with filling rate control. Our work prove that the nonlinear controller can achieve fast and accurate torque closed-loop torque control in various braking conditions compared with the hydrodynamic rate control retarder, and the potential of iris mechanism for adaptive control of hydrodynamic retarder is verified.

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Control of Activated Sludge Plants Based on Measurement of Respiration Rates

Water Science & Technology ◽

10.2166/wst.1993.0677 ◽

1993 ◽

Vol 28 (11-12) ◽

pp. 369-376 ◽

Cited By ~ 1

Author(s):

Abraham Klapwijk ◽

Henri Spanjers ◽

Hardy Temmink

Keyword(s):

Activated Sludge ◽

Respiration Rate ◽

Flow Rate ◽

Control Strategy ◽

Rate Control ◽

Level Control ◽

Fixed Position ◽

Integral Control ◽

The Third ◽

Respiration Rates

An integral control strategy for activated sludge plants presented in this paper consists of three low-level control tasks. The first is the actual respiration rate control by manipulating the influent flow rate, whereby the aerators are at a fixed position for each setpoint. The second task is the maximum respiration rate control by manipulating the waste activated sludge flow rate. The third task of the integral control strategy is the instantaneous respiration rate monitoring, which informs the operator about the performance of the process.

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Torque Ripple Minimization in Direct Torque Control based IM Drive Part-I: Single-rate Control Strategy

2008 Joint International Conference on Power System Technology and IEEE Power India Conference ◽

10.1109/icpst.2008.4745192 ◽

2008 ◽

Cited By ~ 6

Author(s):

Saurabh N. Pandya ◽

J. K. Chatterjee

Keyword(s):

Control Strategy ◽

Rate Control ◽

Direct Torque Control ◽

Torque Ripple ◽

Torque Control

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Comparison of microcontroller-based and mechanically controlled water rate control systems in solar energy water distillation

Journal of Physics Conference Series ◽

10.1088/1742-6596/1516/1/012019 ◽

2020 ◽

Vol 1516 ◽

pp. 012019

Author(s):

E Parikesit ◽

F R Sambada

Keyword(s):

Solar Energy ◽

Control Systems ◽

Rate Control ◽

Water Distillation ◽

Water Rate

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Optimization of a brownstock washing line

TAPPI Journal ◽

10.32964/tj14.2.83 ◽

2015 ◽

Vol 14 (2) ◽

pp. 83-91 ◽

Cited By ~ 1

Author(s):

RIKU KOPRA ◽

KIMMO KOIVULA ◽

OLLI DAHL

Keyword(s):

Control System ◽

Real Time ◽

Water Consumption ◽

Torque Control ◽

Wash Water ◽

Dilution Factor ◽

Level Control ◽

Level Control System ◽

Chemical Pulp ◽

Upper Level

The objective of this study was to improve the efficiency of a certain Scandinavian chemical pulp mill’s brownstock washing line. The information was collected by using online devices (a refractometer and a conductivity meter), and the whole line was controlled by an upper level control system. The results indicate that it is possible to reduce the amount of brownstock washing loss by controlling the dilution factor (DF) of the entire brownstock washing line, via the use of torque control of washers and real time wash loss measurements. Simultaneously, the amount of used wash water is decreased, thus significantly improving the economic efficiency of the fiber line, especially in the evaporation and bleaching plant. Real time dissolved dry solids (DDS) measurements proved useful for controlling and monitoring the wash loss and water consumption.

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Analysis and Control Design of a Hydro-Mechanical Hydraulic Hybrid Passenger Vehicle

ASME 2009 Dynamic Systems and Control Conference, Volume 2 ◽

10.1115/dscc2009-2616 ◽

2009 ◽

Cited By ~ 2

Author(s):

Teck Ping Sim ◽

Perry Y. Li

Keyword(s):

Control Systems ◽

Torque Control ◽

Mechanical Transmission ◽

Control Analysis ◽

Passenger Vehicle ◽

Level Control ◽

Analysis And Design ◽

Low Level ◽

Hydraulic Hybrid ◽

High Level

This paper gives the dynamic analysis of a hydro-mechanical transmission (HMT) drive train with regeneration and independent wheel torque control of a hydraulic hybrid passenger vehicle. From this analysis, we formulate the HMT control system, which is made up of high, mid and low-level control systems. The high-level consists of a state of charge management and the mid-level translates the storage requirement specified by the high-level into desired internal speed and gear ratio to be executed by the low-level. In this paper we focus on the low-level control analysis and design, where the actuation authority to regulate the internal speed variable comes from either the engine (mode 1) or the hydraulic system (mode 2). Experimental studies show good tracking performance of the proposed control systems and enable our vehicle system to be driven in the proposed HMT architecture.

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Control and Experimental Validation of a Powered Knee and Ankle Prosthetic Device

Volume 1: Advances in Control Design Methods; Advances in Nonlinear Control; Advances in Robotics; Assistive and Rehabilitation Robotics; Automotive Dynamics and Emerging Powertrain Technologies; Automotive Systems; Bio Engineering Applications; Bio-Mechatronics and Physical Human Robot Interaction; Biomedical and Neural Systems; Biomedical and Neural Systems Modeling, Diagnostics, and Healthcare ◽

10.1115/dscc2018-9218 ◽

2018 ◽

Cited By ~ 1

Author(s):

Krishan Bhakta ◽

Jonathan Camargo ◽

Aaron J. Young

Keyword(s):

Pid Control ◽

Torque Control ◽

Level Control ◽

Transfemoral Amputation ◽

Prosthetic Device ◽

Low Level ◽

Impedance Parameters ◽

High Level ◽

Kinetics Of ◽

Kinematics And Kinetics

Developing active prostheses require robust design methodologies and smart controllers in order to appropriately provide net positive mechanical work to the user. Passive prostheses are limited in their ability to sustain walking for long periods of time as well as ambulating over different terrains/environmental conditions. In this paper we present a control architecture and validation results on three individuals with transfemoral amputation using our powered knee and ankle prosthetic device. A three stage controller structure is proposed: high-level control, mid-level control, and low-level control. The high-level controller is responsible for determining the locomotion mode. At the mid-level control, an impedance controller is paired with a state machine to coordinate the kinematics and kinetics of the device with the user during community ambulation tasks. At the low-level control, the device is paired in conjunction with a series elastic actuator (SEA) at each joint to enable closed-loop torque control (PID control). Our results indicate that our powered prosthetic device is capable of scaling to a range of speeds without having to tune many impedance parameters. Our approach shows that our device is a good platform for further testing robust controllers that can provide powered assistance to the user.

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