São Paulo Federal Institute of Education, Science and Technology

About: São Paulo Federal Institute of Education, Science and Technology is a education organization based out in São Paulo, Brazil. It is known for research contribution in the topics: Context (language use) & Computer science. The organization has 1707 authors who have published 2374 publications receiving 11333 citations.

Optimal voltage regulation in distribution systems with unbalanced loads and distributed generation

Abstract: This paper proposes optimal voltage control strategies for distribution systems that have multiple voltage regulator devices. The system must operate reaching desirable voltage profiles for scenarios that consider extreme loading (heavy and light), unbalanced loads and distributed generation connection. The problem is modeled as an optimization problem that ensures the attendance of the constraints related to voltage limits, power balance and control devices' capacity. The decision variables are the taps of the voltage control devices, which play an important role on Volt/Var control. A genetic algorithm implemented through a computer interface between Matlab and OpenDSS packages determines the number of control operations. It is assumed that the distribution system has a centralized control with all necessary communication infrastructure. To confirm the validity of the proposed method, simulations were performed by using the IEEE 34 node test feeder. The results showed that the strategies contributed to reduce the voltage deviation along the feeder, the voltage unbalance and the total feeder losses.

Evaluation of the Efficiency of Basic Sanitation Integrated Management in Brazilian Municipalities.

Abstract: This study aims to evaluate the level of technical efficiency of companies that perform the integrated management of basic sanitation in Brazilian municipalities. A Multiple Data Envelopment Analysis (M-DEA) model was applied to estimate the performance of water supply and sewage services in 1628 municipalities covering more than 56% of the Brazilian population, identifying the factors that most influence the efficiency of the sector in the years 2008 and 2016. The M-DEA methodology is an extension of Data Envelopment Analysis (DEA) with multiple DEA executions considering all combinations of inputs and outputs to calculate efficiency scores. The methodology reduces possible biases in the selection of resources and products of the model, ability to support decision-making in favor of improvements in the sector′s efficiency based on national regulatory framework. The analyses show that the companies analyzed can increase their operating results and attendance coverage by more than 60%, given the current levels of infrastructure, human and financial resources in the sector. Based on the simulation of potential efficiency gains in Brazilian basic sanitation companies, the estimates show that the coverage of the population with access to sanitary sewage would go from the current 59.9% to 76.5%. The evidence found provides indications to subsidize sanitation management in the country at the micro-analytical level, enabling a better competitive position in the sector for the integrated management of basic sanitation and its universalization in Brazil.

Modeling study of an Implantable Centrifugal Blood Pump actuator with redundant sensorless control

Abstract: The permanent magnet brushless direct current motor (BLDC), have been the main component in most of the Ventricular Assist Devices (VAD) development. An Implantable Centrifugal Blood Pump is being developed at the Institute Dante Pazzanese of Cardiology (IDPC) as VAD to assist patients with cardiovascular diseases. To develop a high performance controller is necessary to have a reliable virtual model of the BLDC. Toolbox SimPowerSystems software package was used to study the dynamic system. Permant Magnet Synchronous Machine (PMSM)block implements the differential equations for the motor through a state-space model, this is main contribution of this work. Sensorless control was used as redundant position rotor control. The model showed satisfactory results when compared with data given by the manufacturer in its catalog. In future works, the results presented in this work will be used to improve the motor model. Thus, it will allow reliable simulations of new proposed controllers.