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Three-phase current source rectifier is a very good solution for connecting photovoltaic modules to the grid because of its boosting nature. However, an LC filter included on the grid side enhances grid current distortions. Proper control can reduce the impact of those disadvantages. The paper presents a new FCS-MPC method for the CSI combined with MPPT algorithm. The algorithm provides unity power factor and low grid current distortions, proven in simulation results.

Compared with the typical three-phase voltage converter, the current source rectifier is very interesting front-end converter because of its buck-type nature and low electromagnetic interferences. However, it includes LC filter, which causes distortions of the grid currents and enhances the reactive power. Proper control algorithm can fix those disadvantages. The chosen option is finite control set model predictive control. It is a comprehensive tool because of the flexibility in cost function establishment. Simulation results proof good performance of the system in normal and distorted supplying voltage conditions. Distortions are reduced and unity power factor is obtained. Concluding, the method can be used in low voltage DC loads feeding, battery charging and active power filtering applications.

Three-phase current source rectifier (CSR) is becoming more popular in industry as front-end converter because its four-quadrant work and low electromagnetic interferences. However, it includes LC filter on the input side, which lowers efficiency and enhances distortions of grid currents. Impact of those disadvantages can be reduced by proper control algorithm. The purpose of this paper is to present a new predictive control strategy of the CSR providing low grid currents distortions and unity power factor. The algorithm chooses proper space vector of the rectifier according to the predicted value of the DC current and predicted value of the capacitor voltage. Proposed method is analysed for different reference values. Simulation results confirm good performance of the system, distortions are reduced and unity power factor is obtained. The method is useful in many applications, including low voltage DC loads feeding and active power filtering.

The paper presents a new predictive control strategy of current source rectifier (CSR) supplied from the grid. The algorithm chooses proper space vector of CSR according to the predicted value of the grid current and predicted value of the capacitor voltage. Proposed method is analyzed for different L and C values and their influence on higher harmonics reduction has been discussed. Simulation results confirm good performance of the system.

The issue of information overload is quite well resolved in the area of textual documents available on the net by using the paradigm of information filtering. However, as the idea of applications of Internet is still changing and evolving into the more and more dynamic concept connected with the paradigm of Web services, there also appears a need for filtering of different objects. In this paper the concept of application-oriented Web services filtering is discussed. As the proof-of-concept the F-WebS (filtering of Web services) system is presented.