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Bulk power transmission across long distances has been mostly based in High Voltage Alternated Current solutions, not only due to their flexibility and cost, but also driven by the broad available portfolio. However, this solution has known physical boundaries which are quite relevant especially under the analysis of long-distance offshore wind farm applications. The aim of this paper is to present...
The central objective of this paper is to investigate the harmonic behavior of 110-kV overhead lines. For this purpose, a method to describe the frequency-dependent series impedance and shunt admittance per unit length has been developed using the symmetrical components. The developed method uses input data that has been generated using the simulation software PSCAD. This paper begins by presenting...
This paper presents a simple modulation algorithm which accomplishes the voltage balance across the capacitors of a Cascaded H-bridge (CHB) converter using zero voltage injection. CHB converters are widely used in renewable energy production, especially in solar plants due to their modularity. This advantage can also become a problem when the power generated by the solar cell or consumed by a load...
This paper introduces a new transformerless converter topology for Multiphase-Based Wind Energy Conversion Systems (WECSs). In this topology, a twelve-phase induction generator is integrated to the grid using dual Nine-Switch Converters (NSCs) connected in series forming a high voltage cascaded dc-link. For this generator phase number, this topology reduces the total number of semiconductor devices...
The virtual power method can effectively decouple the inverter output active and reactive power. However, in case of parallel operation the output powers may not be shared very well because of the line impedances mismatching. Therefore, if the system impedances are set to be equal through the virtual impedance loop, then the virtual power loop can successfully share the power. This simply means unifying...
Multiphase motors are being used in high power electric transportation applications owing to their advantage such as high reliability, efficiency and fault-tolerant capability. A high power density drive system is needed to reduce the losses and increase heat-sinking capability. In this paper, the power drive module is packed using Silicon Carbide (SiC) MOSFET devices as they are capable of operating...
In general, the distributed generation (DG) inverters can operate in parallel in islanded microgrids through droop characteristic based control technique. This control technique is suitable for long distance DG inverters to achieve proper power sharing while ensuring good voltage regulation. On the other hand, the traditional droop control shows some disadvantages, such as the requirement for multi-loop...
In recent years, Active Magnetic Bears (AMBs) becoming attractive for several reason such as frictionless rotation, high reliability and high speed operation. Moreover, AMBs are today an interesting alternative to standard bearing due to power electronics and control hardware price reduction, but the main disadvantage of AMBs is that they are design to have a small airgap and a high stiffness. This...
A Single Phase Dynamic Voltage Restorer (DVR) based on five-level ground point shifting multilevel inverter topology has been proposed in this paper. The proposed inverter has a floating ground point. Therefore, by shifting the ground point, it is observed that the inverter circuit gives five output voltage levels from single DC voltage source. This configuration uses less number of switches compared...
The paper describes graph-based approach, which allows introducing the process of electric energy transmission and distribution by means of directed energy flows and cost flows in a network equivalent circuit. The main idea deals with the allocation of electric utilities' energy transport costs between output nodes of an electric network. The methodology proposed can be characterized as two-stage...
The subsynchronous oscillation (SSO) phenomenon may occur in a modular multilevel converter-based high-voltage dc (MMC-HVDC) transmission system for wind farm integration, which has already been observed in the real world. In this paper, the generation mechanism of the SSO phenomenon in the interconnected system is revealed by means of impedance-based analysis. On this base, from the HVDC converter...
Synchronous reluctance motor (SynRM) have rather poor power factor. This paper investigates possible methods to improve the power factor (pf) without impacting its torque density. The study found two possible aspects to improve the power factor with either refining rotor dimensions and followed by current control techniques. Although it is a non-linear mathematical field, it is analysed by analytical...
In this paper, a three phase delta connected self-excited induction generator (SEIG) excited by two capacitors and feeding a single phase load is investigated in both transient and steady state cases. Using symmetrical components analysis, two simple formulas are derived to calculate the required values of the two capacitors that result in balanced stator phase currents under rated conditions, which...
A novel pressure control system based on a centrifugal pump Simulink model is proposed aiming to reduce energy consumption during pump operation. The system developed provides the possibility of power reduction during pressure maintenance with the help of mixed pressure control strategy. To evaluate the system, a series of tests have been conducted that proved that the designed system is more beneficial...
The aim of this work is to develop a robust model for short-term prediction of Photovoltaics (PV) generation. The model is structured with algorithms that belong to the technical field of computational intelligence. This approach provides the potential to form a forecasting system with high flexibility, efficiency and customization. The paper examines various combinations of inputs, in order to fully...
This paper presents a comparision between two controllers for Proton Exchange Membrane Fuel Cell PEMFC power system. The aim of this work is to keep the PEMFC working at its MPP by acting on the DC/DC converter, and ensure an adequate robustness against load and inputs variations. Conventional controller PI and backstepping technique are applied to the DC/DC boost converter. The stability of the backstepping...
The rapid development of rail transit brings a great increment of electricity, in order to reduce the energy consumption and the operating cost, energy storage technology has become a hot focus in the field of rail transit. In this paper, the power loss model of hybrid energy storage system (HESS) is established from the point of efficiency improving, which includes the loss of lithium-ion battery,...
The main goal of this work is to show the advantages of two-phase cooling technology for thermal management of high power electronics modules, with a SKIM909GD066 motor inverter as the test device for thermal/fluid analysis. Dissipated power, heat transfer coefficient and fluid temperature are set in a 3-D FEM (Finite Element Method) based thermal model to simulate two-phase cooling of IGBTs at the...
This paper presents a Lyapunov-function based control approach with cascaded proportional-resonant (PR) controller for single-phase grid-tied LCL-filtered quasi-Z-source inverter (qZSI). The proposed control approach guarantees the global stability of the closed-loop system and zero steady-state error in the grid current. The reference values for the inverter current and capacitor voltage are generated...
This paper presents a 27-Level asymmetric multilevel shunt active power filter topology that allows the compensation of a nonlinear load, as well as the DC voltage regulation thanks to a comprehensive control strategy. The topology considers the ratio 9∶3∶1 in order to generate the AC waveform with a simple staircase modulation algorithm. The dynamic model of the proposed topology is obtained and...
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