An Effective Harmonic Suppression Method Based on Linear Active Disturbance Rejection Control for Copper Electrowinning Rectifier

Because the harmonics in the production process of copper electrowinning have an important impact on the electrical energy consumption, it is necessary to suppress the harmonics effectively. In this paper, a copper electrowinning rectifier with double inverse star circuit is selected as a study object in which a large number of harmonics mainly including the 5th, 7th, 11th, and 13th harmonics are generated and injected back into the power grid. The total harmonic distortion rate of the power grid is up to 29.19% before filtering. Therefore, a method combining the induction filtering method and the active filtering method is proposed to carry out comprehensive filtering. Simulation results demonstrate that the total harmonic distortion rate of the system decreases to 4.20%, which indicates that the proposed method can track the corresponding changes of harmonics when the load changes in real time and filter them out. In order to ensure and improve the effect of active filter, a current harmonic tracking control method based on linear active disturbance rejection control is proposed. Simulation results show that the total harmonic distortion rate decreases to 3.34%, which is also lower than that of hysteresis control. Compared with the conventional single filtering method, the new filtering method combining induction filtering with active filtering based on linear active disturbance rejection control in the copper electrowinning rectifier has obvious advantages.

Inactive capacity compensation device in frequency converters in the composition of electric power systems of marine vehicles

Управление режимами работы гребного электрического двигателя осуществляется полупроводниковыми преобразователями частоты, применение которых значительно ухудшает качество электроэнергии на общих шинах судовых электроэнергетических систем. Основными причинами являются уменьшение коэффициента мощности и появление высших гармоник в потребляемом токе. В результате этого снижается надежность работы потребителей, и увеличиваются потери электроэнергии. Поэтому уменьшение указанных негативных последствий является актуальной задачей. В связи с этим, большое внимание уделяется вопросам, связанным с изучением и разработкой различных методов и устройств обеспечения качества электроэнергии, увеличения коэффициента мощности и фильтрации высших гармоник. В настоящее время, перспективным методов улучшения качества электроэнергии, является применение устройств управления реактивной мощностью и активной фильтрации, т.е. компенсаторов неактивной мощности. Подобные системы можно применять не только для надводных судов, но и в автономных подводных транспортных средствах, в качестве энергетической установки которых выступает батарея топливных элементов. The control of the operating modes of the propulsion electric motor is carried out by semiconductor frequency converters, the use of which significantly degrades the quality of electricity on the common buses of the ship power systems. The main reasons are a decrease in the power factor and the appearance of higher harmonics in the current consumption. As a result, the reliability of the consumers is reduced, and the losses of electricity increase. Therefore, the reduction of these negative consequences is an urgent task. In this regard, much attention is paid to issues related to the study and development of various methods and devices for ensuring the quality of electricity, increasing the power factor and filtering higher harmonics. Currently, a promising method for improving the quality of electricity is the use of reactive power control devices and active filtering, i.e. compensators of inactive power. Such systems can be used not only for surface crafts, but also in autonomous underwater vehicles, the power plant of which is a fuel-cell stack.

RNA Identification Technique and RST Control of a Hybrid Indirect Matrix Converter with a Flying Capacitor Three Level Inverter in Power Active Filtering Application

The present paper deals with RST controller using implementation of neural architectures to control power electronics systems dedicated to power quality improvement in a distribution grid. We present a technique for designing a robust RST controller, The computation of the controller is used to enhance the control a Hybrid Indirect Matrix Converter with a flying capacitor three level inverter (HIMC) coupled to the power grid (PG) by an RL filter, the synthesizing of this RST controller is formulated through open and close loop. Artificial neuronal network (ANN) identification technique is used to define/extract this disturbance. Simulation results by MATLAB, Simscap/sim power system code shows the effectiveness of the proposed method.

An Inductive Active Filtering Method for Low-Voltage Distribution Networks

Three-phase unbalanced and nonlinear loads aggravate harmonic problems in low-voltage distribution networks. In this paper, a hybrid inductive and active filter (HIAF) system with a Ddy converter transformer is proposed. By establishing the circuit and corresponding mathematical models, the working mechanism of the HIAF system in harmonic suppression is analyzed. In the designed HIAF system, we install the detection point on the grid-side winding and the compensation point on the filtering winding. Since both windings have the same connection, no phase compensation between the harmonic detection point and compensation point is demanded. Eventually, we apply a harmonic damping control and zero-value impedance control strategy to realize harmonic suppression under both balanced and unbalanced loads. The simulation results show that the HIAF system can effectively suppress harmonics under various load conditions.

Active filtering capability based on the RSC control of WECS equipped with a DFIG

<p>The increasing integration of decentralized production from renewable energies on the electricity grids should contribute to improving the stability and quality of the energy produced. The main objective of this work is to prove how renewable energy sources can improve the quality of electrical energy in the grid. In particular, controlled by the oriented flux technique, a double - feed induction generator DFIG driven by a wind turbine is together used to produce active power to the electrical network and to compensate the currentharmonics generated by a non - linear load, which leads to improve the supplied energy quality. The Active filtering function consists first of all in identifying the current harmonics using the theory of instantaneous active and reactive powers quality (PQ). Then, the closed loop based on the fast terminal sliding mode control (FTSMC) control allows both the generator to follow the optimal operating point of the wind turbine and to compensate for the current harmonics. The analysis and simulation results using MATLAB/Simulink confirm the effectiveness and the limits of the proposed methods and also show the performances of the law control which provides flexibility, high precision and fast response.</p>