Недавне прослеђене ставке
Сада се приказује 1 - 5 од 17
- СтавкаEXPERIMENTAL VERIFICATION OF THE STRESS DISTRIBUTION IN THE CRANE MAST(Institute of Mechanical Engineering, 2009) Šarenac, Momir; Milutinović, Miroslav; Ličen, Hotimir
- СтавкаEnergy saving in the power plants using automatic control(2011) Nedić, Novak N.; Filipović, Vojislav Ž.; Prodanović, Saša Lj.The constant striving to reduce energy consumption leads toward introduction of strategies, which can enable it. In this paper, the strategy which includes frequency regulators into control system of condensate level in condenser of turbine in thermal power plant Gacko is proposed. Properly tuned PID (proportional-integral-derivative) controllers are precondition for appropriate process control. Therefore, the mathematical model of this system is formed and simulations of auto-tuning of PID controllers, using ideal relay and saturation relay as nonlinearity, are carried out. Static load disturbance are considered too, because of its adverse effect both directly on the object, and in auto-tuning process, which causes errors in determining of PID regulator’s parameters. The justification of the introduction of frequency regulators has been confirmed by calculation of energy saving. Its feasibility was proved through simulation of the functioning of the entire control system of level in condenser, based on consideration of characteristic parameters of system response.
- СтавкаReduced Energy Cost through the Furnace Pressure Control in Power Plants(2012) Filipović, Vojislav Ž.; Nedić, Novak N.; Prodanović, Saša Lj.Maintaining pressure in the boiler’s furnace is one of the key requirements for proper combustion in steam boilers in thermal power plants. This paper proposes a control strategy that eliminates flap in the channel for the output gases. This is achieved by applying the frequency regulator for asynchronous motor speed control. Reference value for the frequency regulator is obtained through the PI controller. Special attention is given to tuning of PI controller. Well-tuned PI controller with the use of frequency regulator provides significant energy savings, because asynchronous motor for ventilator of steam boiler in thermal power plants has a large power. Modification of relay feedback experiment has supported λ-tuning of controller whose two types (faster and robust) were tuned. This modification consists in: a) Replacement of relay characteristic with saturation curve, b) Fourth-order process identification with first-order process plus dead time. The methodology is illustrated by simulations.
- СтавкаAbility of managers for crisis management in small enterprises: study in Bosnia and Herzegovina(2017) Medaković, Vlado; Moljević, Slaviša; Gojković, Ranka; Vasković, SrđanSince the enterprise have been existing, crisis of enterprise is well-known. Researches in area of possible appearance crisis in small and medium size enterprises, and sciense enterprise management which is crisis, have large significance when we talk about survival those enterprises, apropos possible prevention their bancrot. We can see that theory is mostly dedicated to enterprises repairing. The early symptom in sight of crisis and prevention latent crisis of enterprise are pointed up. Crisis management and analysis of strategy for turn out from the crisis, as we can see in this is paper, expand views and enable giving certain recomendations for appliance in practice.
- СтавкаAPPLICATION OF RENEWABLE ENERGY SOURCES IN TERMS OF ECONOMIC, ENVIRONMENTAL AND SOCIAL SUSTAINABILITY(ADEKO (Association for design, elements and structures); Faculty of Mechanical Engineering, University of Montenegro, 2017) JOKANOVIĆ, Mirjana; GOLUBOVIĆ, Dušan; ŠUPIĆ, Blagoje; KOPRIVICA, AleksandraWe are witnesses of everyday changes, which can bring the world into the question of survival. On the other hand, the progress and the speed of changes are the keys of success. What is important is that we have to change the human being’s life, due to the concept of the sustainable development, which includes three dimensions: ecology, economy and social aspect. This paper gives the analysis of using the renewable energy, through the production of the electricity, including the sustainable development. Through research, attention was paid to analyzing the growth in the share of renewable energy in electricity production, as well as incentives to use renewable energy sources, in the area of Republic of Srpska.