Since 1995 Brazil has been applying its labeling program to increase the efficiency of application of many household appliances and equipment. From 2003 on inductions motors have also been receiving the PROCEL2 prize, which helped push motors efficiency over than those limits established by the labeling program. Therefore, this work presents the development of a […]
This paper presents a method for unsteady calibration of rectangular and triangular weirs using height measurement instead of another flow measurement device as a standard. The theoretical equation of the dependence of the flow with the head for that weir, as long as the covered area, must be known. The method is theoretically developed and […]
O presente trabalho busca obter as perdas e o rendimento do motor elétrico pelo método termográfico, o qual parte do princípio de que as perdas em um motor elétrico se dissipam na forma de calor, e o compara com um método tradicional de separação de perdas com medição direta da potência elétrica e mecânica. Ambos […]
This paper presents the application of acoustic Doppler current profiler as a tool for adjustment and validation of computational fluid dynamic models in river environment. The two tailraces of the Tucurui hydro power plant present strong differences. The bed of the left tailrace has a high bank and a curvature oriented towards the right. Thus, an […]
This paper introduces the constant excitation test to be applied in synchronous machines. The results obtained from this test allow the determination of the quadrature axis synchronous reactance of the salient pole synchronous machines. Despite standard present methods for its determination, the proposed method is suitable for large installed machines. The method basis is described […]
Hydropower has long been recognized as a renewable power source. Due to economic reasons, high and medium head potentials have been primarily developed. Later, low-head potentials became a feasible solution with the application of modern Bulb generators. Although Bulb generators have been developed and applied since the 1930s, new techniques and materials have been used […]
Isolated generation in micro hydroeletric power plant (MHPP) through the induction generator (IG) has been the subject of extensive research due to the fact that this type of electrical machine is easy to operate, requires simplified maintenance, and has also a lower cost when compared to the synchronous machine, mainly in the range from 0.5 to […]
Important in many different sectors of the industry, the determination of stream velocity has become more and more important due to measurements precision necessity, in order to determine the right production rates, determine the volumetric production of undesired fluid, establish automated controls based on these measurements avoiding over-flooding or over-production, guaranteeing accurate predictive maintenance, etc. […]
This work aims at estimating the losses of a three-phase induction motor using the thermography techniques, which assumes that all the losses of the motor are dissipated as heat. The proposed technique is compared to the traditional method of losses segregation with direct measurement of the electric and mechanical power. Results statistically treated are also […]
The paper presents a novel methodology for the operation of those hydro power plants provided with a single penstock by the optimal distribution of the dispatched power among its available generating units, aiming at the maximum efficiency of the whole power plant energy conversion. While previous optimization methods made use of off-line static curve and […]