Comparison between the Conventional Methods and PSO Based MPPT Algorithm for Photovoltaic Systems

Since the output characteristics of Photovoltaic (PV) system depends on the ambient temperature, solar radiation and load impedance, its maximum Power Point (MPP) is not constant. Under each condition PV module has a point at which it can produce its MPP. Therefore, a Maximum Power Point Tracking (MPPT) method is needed to uphold the PV panel operating at its MPP. This paper presents comparative study between the conventional MPPT methods used in (PV) system: Perturb and Observe (P&O), Incremental Conductance (IncCond), and Particle Swarm Optimization (PSO) algorithm for (MPPT) of (PV) system. To evaluate the study, the proposed PSO MPPT is implemented on a DC-DC converter and has been compared with P&O and INcond methods in terms of their tracking speed, accuracy and performance by using the Matlab tool Simulink. The simulation result shows that the proposed algorithm is simple, and is superior to the P&O and IncCond methods

Investigation of multi-phase tubular permanent magnet linear generator for wave energy converters

In this article, an investigation into different magnetization topologies for a long stator tubular permanent magnet linear generator is performed through a comparison based on the cogging force disturbance, the power output, and the cost of the raw materials of the machines. The results obtained from finite element analysis simulation are compared with an existing linear generator described in [1]. To ensure accurate results, the generator developed in [1] is built with 3D CAD and simulated using the finite-element method, and the obtained results are verified with the source.The PRIMaRE project

Reactive Power Control of PV Inverters in Active Distribution Grids with High PV Penetration

Copyright . Photovoltaic (PV) systems can reduce greenhouse gas emissions while providing rapid reactive power support to the electric grid. At the distribution grid level, the PV inverters are controlled to reduce the system’s active power loss and to address problems caused by the PV systems themselves. For example, the distribution grid may face overvoltages due to high PV generation during off-peak hours. In this paper, a reactive power control approach for PV inverters is proposed to control the injection/absorption of reactive power to reduce the active power loss of the system while solving the overvoltage problem. To achieve this, the proposed controller periodically dispatches the reactive power setpoints and applies a real-time volt/var algorithm. The proposed method uses probabilistic distributions to account for the uncertainties in PV generation and load demand. The controller is implemented at the lateral level which simplifies the required communication platform and reduces the computational cost. The real-time volt/var control coordinates the operation of the different inverters during overvoltage conditions so that the voltage rise is limited using as little reactive power as possible by the inverters. Accordingly, the active power loss due to reactive power flow in the system is reduced. Two distribution systems are simulated using Open Distribution System Simulator (OpenDSS) and used to evaluate the proposed controller and compare with two other methods. A daily time series simulation is performed to test different operating conditions. The simulation results show that the proposed controller is able to reduce the active power loss in general and solve the overvoltage problem with a lower reactive power requirement than the other volt/var methods.10.13039/501100000308-British Council (Grant Number: 623801791); 10.13039/501100004410-T?rkiye Bilimsel ve Teknolojik Ara?t?rma Kurumu (Grant Number: 120N996)

Practical Solutions for Harmonics Problems Produced in the Distribution Networks

Harmonic distortion on the power system is a modern concern due to the technological advances in silicon technology as it presents an increased non-linear loading of the power system. The effects of harmonics are well known: customers could experience major production losses due to the loss of supply as an example, on the other hand, harmonic load currents cause the utility to supply a higher real energy input then the actual real power needed to maintain a plant’s production at a certain level. The utility carries the extra transmission losses due to the harmonic currents. Different solutions will be reviewed as concepts for solving certain types of problems related to power quality. Both theoretical and a case study are presented

Regular paper Practical Solutions for Harmonics Problems Produced in the Distribution Networks

JES Journal of Electrical Systems Harmonic distortion on the power system is a modern concern due to the technological advances in silicon technology as it presents an increased non-linear loading of the power system. The effects of harmonics are well known: customers could experience major production losses due to the loss of supply as an example, on the other hand, harmonic load currents cause the utility to supply a higher real energy input then the actual real power needed to maintain a plant's production at a certain level. The utility carries the extra transmission losses due to the harmonic currents. Different solutions will be reviewed as concepts for solving certain types of problems related to power quality. Both theoretical and a case study are presented

High frequency directional-based protection scheme for transmission lines emanating from large scale wind farms

Penetration of large-scale renewables has changed the fault current characteristics, degrading reliability of the transmission line traditional protection system. This paper presents a high frequency directional-based protection scheme for transmission lines connecting large scale wind farms to the high voltage grid. The proposed protection mitigates the negative influence of the wind farm response to faults on the fundamental frequency phasors by using the high frequency components generated during the fault. The proposed protection scheme is applied to the relays at both sides of the protected transmission line independently. Therefore, each relay utilizes its locally measured voltage and current signals. Then, the relays share their individual decisions to obtain the final decision using the proposed operation logic. In addition, the proposed protection scheme does not require a compensation algorithm for the line capacitive current. An assessment study is conducted on the PSCAD/EMTDC software considering different fault types including cross-country and evolving faults, fault locations, fault resistance values up to 500 Ω, line lengths up to 200 km, and output power of the wind farm. The simulation results emphasize the dependability and security of the proposed protection scheme at different test conditions

A state of the art review of control techniques for power electronics converter based distributed generation systems in different modes of operation

This paper presents an overview of the state of the art techniques in inverter-based distribution generation systems. Different control techniques and classification of inverter modules operated in grid and islanded modes are investigated. The merits and drawbacks of each technique are presented. The operation of the inverter is classified into, single and parallel operation. Parallel operation is used to increase the reliability but some techniques require communications links between the inverter modules. The problem of circulation current between different parallel inverters is investigated.Scopu