Pumping processes often require different operating conditions for the same pipeline. The conditions downstream in the pipeline can change in such a way that the pressure at the discharge of the pump may vary, which automatically introduces changes in the flow supplied by the pump into the pipeline due to the head vs flow characteristic curve of the pump. Even under varying pipeline pressure conditions, it may be necessary to keep the flow discharge of the pump constant. The two most commonly used control strategies for flow control with centrifugal pumps are by means of a fixed-speed pump and a control valve at the outlet of the pump, or by means of a variable frequency drive which avoids the need for the control valve. It has been demonstrated that the approach with the fixed-speed pump and the control valve provides poor power efficiency results, so a variable frequency drive is normally the solution of choice in industry applications. The use of a variable frequency drive allows reaching the flow required by the system without changing the physical characteristic of the pump or pipeline, i.e., it is not necessary to shut the system down to replace the impeller of the pump. However, affinity laws of centrifugal pumps dictate that a change in the rotational speed of the impeller shifts the characteristic curves of the pump, not only the flow vs head curve, but also the efficiency curves, among others. Besides, searching for a different operating point by changing the speed of the pump does not necessarily guarantees optimal operating power efficiency. This paper proposes an optimization approach where a compromise is made between flow control and power efficiency by minimizing the error in the flow rate while at the same time maximizing the power efficiency. To accomplish this goal, this paper presents the modeling of the pump and pipeline, and the design of a linear quadratic regulator control for the fluid flow passing through a given pipeline. The fluid under consideration is water. The mathematical model of the overall system is derived by considering the model of an AC motor, the pump and the hydraulic circuit. Then, with the help of the software MATLAB, the controller was designed and implemented with the linearized mathematical model. The actuator of the control system is the variable frequency drive that changes the speed of the impeller to adjust the flow rate to the required operating point under different loading conditions. The results show the behavior of the compensated system with the optimal controller. In practice, the control system must take into account the constraints of the control effort, which means, the frequency of the pump must be kept within safe values to achieve proper functioning of the pumping system.
Industrial automation has become an area in full development and of great importance for all industrial sectors since it allows to improve the productivity of companies and the quality of their products. Currently, factories (i.e., small, or medium) must implement new technologies to increase its production and provide qualified products to enter with force in regional markets and nationals. This article shows the design and start up of an automatic palletizer which will have a manual mode in which each actuator in the system can be operated independently; and an automatic mode that will organize the input elements in the previously established way. For companies that produce in batches, is important to reduce storage spaces in warehouses, dispose of their products in an orderly and practical way for their subsequent dispatch. This last process must be effective and fast so as not to generate inconveniences in the delivery of orders to buyers. Our project is focused to the footwear sector, especially, how to seek greater development and performance of these companies where the packaging time of their products can be optimized so that it can be used in other tasks within the company. Also, the result of this investigation shows the engineering process carried out to obtain a prototype of a functional, automatic, productive, quality, and economic product that meets the customer’s requirements. Improvements that will do and future work are included too.
Semi-Active Suspension Systems are very important to achieve comfort, ride handling, ground contact of the tyre, road-friendliness and works in a large range of operation. Its use an active dampers and the action of control is very good because of low energy consumption. The force of the damper is regulated according to the operating conditions. Magnetorheological Dampers are commonly used because of his yield resistance, low power, fast response and low cost of production. However, they behave in a non-linear way, following a dynamic of hysteresis so you should give a more sophisticated mathematical treatment. In this paper, we describe the modelling and design of two control strategies for Semi-Active Suspension System. Two control laws will be developed; classical PID and Fuzzy Logic controls law with the simulation and evaluate the stability and performance properties of our controllers in several different scenarios through analysis and simulation simultaneously. The performance of the system is determined by computer simulation in Matlab/ Simulink. The results obtained to compare and prove the effectiveness of these control approaches.
Bearings are the major components in rotary machinery and very used in the industry. The time for bearing failures identification before interrupting operation or affecting product quality is the basis for most predictive maintenance programs. Taking readings, keeping history of failures and evaluating these results in the operation of rotating equipment on a regular basis, allows to detect possible failures before they become catastrophic. In this way, the damages or defects that are detected before a failure occurs, reduce the repair costs and the time that a rotating machine will be inactive. The bearing failures can generate losses due to machine downtime, unwanted vibration, noise and damage of other components, but if they are detected in time, repair costs and downtime are minimal. This article shows in detail the different detection and classification techniques most used to identify bearing failures such as vibration analysis, artificial neural networks (i.e ANN), convolutional neural networks (i.e CNN) and support vector machine (i.e SVM) and the relevant features of each detection technique.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.