scholarly journals A Fuzzy Based Improved Control Strategy of Dynamic Voltage Restorer for Low Voltage and High Voltage Ride Through Compensation for Variable Speed Hybrid Energy 

Author(s):  
Uthra R ◽  
Suchitra D

Abstract In present-day power generation systems, the integration of many renewable energy sources creating more sustainable hybrid energy network can be witnessed. The Hybrid energy system regulates the escalation in the cost of the energy that are linked with currently established energy resources. One such predominantly used Hybrid energy system happens to be Wind / Photo Voltaic (PV) integrated system which is a viable alternative to meet the rising energy demands.Fault Ride Through (FRT) is one of the cardinal essentialities that is perceived as an indispensable grid code because the effect of faults may propagate to a larger geographical area if FRT is not achieved. In a Hybrid system the ability of the generator to remain connected at the time of short electric fault like voltage dip is identified as Low Voltage Ride Through (LVRT) and voltage swell is known as High Voltage Ride Through (HVRT). When fault occurs at the point of the grid, LVRT or HVRT depending on the fault has to be determined and a pertinent compensation should be carried out. This paper proposes a compensation technique based on Dynamic Voltage Restorer (DVR) employing fuzzy controller for LVRT and HVRT in hybrid systems. The disparityin the voltage at PCC is traced and is used to inject the necessary deficit voltage in case of sag or suppress the excessive voltage in case of swell in the hybrid system by means of DVR. This compensation in turn enables the parameters like DC link and stator voltage to stay within the admissible limits in the event of fault at the point of grid.

Doubly Fed Induction Generator (DFIG) based wind Energy System are very sensitive to grid disturbance such as Symmetrical voltage sag. In this paper the authors propose a new method for application of Dynamic Voltage Restorer for enhancing the low voltage ride through capability of wind turbine driven Doubly Fed Induction Generator.


Author(s):  
Peter Ozaveshe Oviroh ◽  
Tien-Chien Jen ◽  
Nosa Idusuyi ◽  
Olushola Gbadeyan

The rapid increase in global communication infrastructure in developing countries has drawn significant attention to the telecom sector. However, the dismal performance of the power sector in some countries like Nigeria poses a great challenge to the telecom industry which requires a reliable, efficient and environmentally friendly energy supply. Unstable electric grids, an erratic power supply, non-availability of trained and skilled personnel, and a prohibitive cost of site maintenance cumulatively have increased the need to harness abundant renewable energy sources, such as solar and wind. A comparative study of the viability of solar-diesel hybrid against diesel-only generator systems in powering a base station using the cost of kilowatt hour (kWh) self-generated electricity and levelised cost of energy (LCOE) was undertaken using data from some sites located in the Southwest (SW) and the Northeast (NE) regions of Nigeria. Homer Pro Software was used in data analysis. The results obtained showed that with a hybrid energy system (solar and diesel generator), there were 79% savings in fuel consumption, 83.2% savings in operation and maintenance cost for the hybrid energy system in the SW. The savings on fueling as a result of the use of hybrid systems was 86%, and the carbon footprint reduction was 76%. Furthermore, the cost of operation was reduced by 51% for Northeast. The LCOE for the solar hybrid system was determined to be $1.44 for NE1A and NE1B while that of NE2A was $1.46 and NE2B $1.47.


2020 ◽  
Vol 19 (1) ◽  
pp. 9-16
Author(s):  
Musayyibi Shuaibu ◽  
Adamu Saidu Abubakar

Renewable energy sources (RES) are being integrated to electrical grid to complement the conventional sources in meeting up with global electrical energy demand. Among the RES, Wind Energy Conversion Systems (WECS) have gained global electricity market competitiveness especially the Doubly Fed Induction Generator (DFIG)-based Wind Turbines (WTs) because of flexible regulation of active and reactive power, higher power quality, variable speed operation, four quadrant converter operation and better dynamic performance. Grid connected DFIG-based WTs are prone to disturbances due to faults in the network which made the utilization of the power generated a major concern. The grid code requirement for integrating the DFIGs to grid specified that they must remain connected and support the grid stability during grid disturbances of up to 1500milliseconds. The ability of the DFIG WT system to uphold to the grid codes requirement is termed the Fault Ride – Through (FRT). This paper presented a 1.5MW grid connected DFIG-based WT model with a Dynamic Voltage Restorer (DVR) for FRT capability enhancement. The design and simulation were performed in MATLAB/Simulink software. The test system was subjected to disturbances leading to Low Voltage Ride – Through (LVRT), Zero Voltage Ride – Through (ZVRT) and High Voltage Ride – Through (HVRT) considering three – phase balanced fault and single line to ground fault. The performance of improved model of DVR shows enhancement over conventional DVR in terms of voltage compensation and fault current mitigation.


Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2108
Author(s):  
Mohamed Yassine Allani ◽  
Jamel Riahi ◽  
Silvano Vergura ◽  
Abdelkader Mami

The development and optimization of a hybrid system composed of photovoltaic panels, wind turbines, converters, and batteries connected to the grid, is first presented. To generate the maximum power, two maximum power point tracker controllers based on fuzzy logic are required and a battery controller is used for the regulation of the DC voltage. When the power source varies, a high-voltage supply is incorporated (high gain DC-DC converter controlled by fuzzy logic) to boost the 24 V provided by the DC bus to the inverter voltage of about 400 V and to reduce energy losses to maximize the system performance. The inverter and the LCL filter allow for the integration of this hybrid system with AC loads and the grid. Moreover, a hardware solution for the field programmable gate arrays-based implementation of the controllers is proposed. The combination of these controllers was synthesized using the Integrated Synthesis Environment Design Suite software (Version: 14.7, City: Tunis, Country: Tunisia) and was successfully implemented on Field Programmable Gate Arrays Spartan 3E. The innovative design provides a suitable architecture based on power converters and control strategies that are dedicated to the proposed hybrid system to ensure system reliability. This implementation can provide a high level of flexibility that can facilitate the upgrade of a control system by simply updating or modifying the proposed algorithm running on the field programmable gate arrays board. The simulation results, using Matlab/Simulink (Version: 2016b, City: Tunis, Country: Tunisia, verify the efficiency of the proposed solution when the environmental conditions change. This study focused on the development and optimization of an electrical system control strategy to manage the produced energy and to coordinate the performance of the hybrid energy system. The paper proposes a combined photovoltaic and wind energy system, supported by a battery acting as an energy storage system. In addition, a bi-directional converter charges/discharges the battery, while a high-voltage gain converter connects them to the DC bus. The use of a battery is useful to compensate for the mismatch between the power demanded by the load and the power generated by the hybrid energy systems. The proposed field programmable gate arrays (FPGA)-based controllers ensure a fast time response by making control executable in real time.


2014 ◽  
Vol 573 ◽  
pp. 716-721
Author(s):  
S. Rajeshbabu ◽  
B.V. Manikandan

Renewable energy sources provide the additional/satisfy the power to the consumer through power electronics interfaces and integrated with the grid. In grid integration power quality is one of the important parameter that need to be paying more attention. This proposed work focuses on power quality issues in a grid connected renewable energy system. Power quality issues will arises due to many factors here with the by introducing a fault condition in a grid connected renewable energy system the measurements were made at the point of common coupling and the mitigation is done with the help of a dynamic voltage restorer. The dynamic voltage restorer is a device which offers series compensation activated by neural network based controller. The sag improvement and the total harmonic assessment were made at the point of common coupling. Keywords: Neural network, Point of common coupling, Renewable energy source, Power quality, Dynamic voltage restorer ,electric grid.


Author(s):  
Jamal Abdul-Kareem Mohammed ◽  
Arkan Ahmed Hussein ◽  
Sahar R. Al-Sakini

<p>Power distribution network in Iraq still suffers from significant problems regarding electricity distribution level. The most important problem is the disturbances that are occurring on lines voltages, which in turn, will negatively affect sensitive loads they feed on. Protection of these loads could be achieved efficiently and economically using the dynamic voltage restorer DVR when installed between the voltage source and load to inject required compensation voltage to the network during the disturbances period. The DVR mitigates these disturbances via restoring the load voltage to a pre-fault value within a few milliseconds. To control the DVR work, dq0 transformation concept and PID method with sinusoidal pulse-width modulation SPWM based converter had been used to correct the disturbances and thus enhance the power quality of the distribution network. The DVR performance was tested by MATLAB/Simulink with all kinds of expected voltage disturbances and results investigated the effectiveness of the proposed method.</p>


Sign in / Sign up

Export Citation Format

Share Document