A. V. Pavan Kumar

Implementation of MPPT control using fuzzy logic in solar-wind hybrid power system

The renewable energy sources such as Solar energy and Wind energy are complementary by nature. Utilizing these natural resources to produce power will reduce the power demand on the conventional power generation sector. One of the applications of Solar-Wind hybrid power system (SWHPS) is to reduce the amount of power consumed from the conventional power generation to charge the storage reserves present in the system. The SWHPS comprises of Photovoltaic array, wind turbine, Permanent Magnet Synchronous generator (PMSG), controller and converter. The efficiency of the SWHPS depends on the MPPT controller, which makes the Photovoltaic (PV) and wind power generation system to operate at its maximum power. In PV system Perturb & Observe (P&O) algorithm is used as control logic for the Maximum Power Point Tracking (MPPT) controller and Hill Climb Search (HCS) algorithm is used as MPPT control logic for the Wind power system in order to maximizing the power generated. This paper presents a comparative analysis of MPPT controller built using P&O for PV system and HCS for Wind power system, with MPPT controller implemented using Fuzzy Logic control (FLC) in the both the renewable sources in the hybrid system. The performance of the different implementation of MPPT controllers in the hybrid system are investigated in this paper in MATLAB, Simulink. The SWHPS with the FLC based MPPT has shown to have a better, faster control as compared with the other controllers.

Performance Analysis of a Two-Diode model of PV cell for PV based generation in MATLAB

The increase in concern for carbon emission and reduction in natural resources for conventional power generation, the renewable energy based generation such as Wind, Photovoltaic (PV), and Fuel cell has gained importance. Out of which the PV based generation has gained significance due to availability of abundant sunlight. As the Solar power conversion is a low efficient conversion process, accurate and reliable, modeling of solar cell is important. Due to the non-linear nature of diode based PV model, the accurate design of PV cell is a difficult task. A built-in model of PV cell is available in Simscape, Simelectronics library, Matlab. The equivalent circuit parameters have to be computed from data sheet and incorporated into the model. However it acts as a stiff source when implemented with a MPPT controller. Henceforth, to overcome this drawback, in this paper a two-diode model of PV cell is implemented in Matlab Simulink with reduced four required parameters along with similar configuration of the built-in model. This model allows incorporation of MPPT controller. The I-V and P-V characteristics of these two models are investigated under different insolation levels. A PV based generation system feeding a DC load is designed and investigated using these two models and further implemented with MPPT based on P&O technique.

Investigation of small PMSG based wind turbine for variable wind speed

In order to investigate small wind turbines, a comprehensive knowledge of mechanical and electrical parameters is required. Permanent Magnet Synchronous Generator (PMSG) is one of the kinds which are widely used for variable speed and direct driven wind power generating. In order to predict the amount of power that can be extracted by the wind turbine in a concerned area the knowledge of wind speed pattern for that particular location is required. In this paper a case study is selected to study the wind pattern and investigate the performance of the PMSG based wind power generation system for fixed speed and variable speed conditions. Wind power generation system simulated using MATLAB / Simulink consisting of wind turbine, PMSG, diode rectifier, Maximum Power Point tracking (MPPT) controlled boost converter, and DC load is considered. The Hill Climbing Search (HCS) algorithm is implemented using Fuzzy Logic Controller (FLC) for MPPT. The effectiveness of PMSG based wind power generation in the case study is investigated with the environmental conditions recorded at BITS-Pilani, Hyderabad campus, Telangana, India.

Application of Dynamic Voltage Restorer in microgrid for voltage sag/swell mitigation

Microgrids are becoming increasingly attractive to consumers as it allows utilization of freely available renewable energy sources. They are usually installed at consumers sites i.e the distribution end. Due to high penetration of distributed generation units with different types of loads, microgrids can cause power quality and power control issues. Some of them are voltage swells and sags, and low power factor which further require reactive power compensation. This paper presents the utilization of the custom power device specifically Dynamic Voltage Restorer (DVR) in mitigating the problem of voltage sags and swells occurring in microgrid. A microgrid is modeled and simulated with different loading conditions causing power quality problems. The performance of DVR, installed in microgrid, is analyzed for reactive power compensation to overcome these concerned issues. The control logic of DVR is designed using phase locked loop (PLL) technique and its effectiveness is observed in Matlab/Simulink.

Microgrid reactive power compensation using UPQC with common DC link energy restored by PV array

Microgrids (MG) are turning out to be progressively appealing to consumers and an incredible number of them will be introduced at their premises in the near future as they allow utilization of freely available renewable energy sources. Because of high penetration of distributed generation units with distinctive sorts of loads, microgrids can be subjected to power quality and control issues. Some of them are voltage swells and sags, and low power factor which further oblige reactive power compensation. This paper exhibits the custom power device particularly Unified Power Quality Conditioner (UPQC) in alleviating the issue of voltage sags and swells happening in microgrid. A microgrid is modelled and simulated with diverse loading conditions bringing on power quality issues. The incorporation of UPQC in microgrid is analyzed for providing reactive power compensation to overcome these concerned issues. In addition Photo Voltaic based common DC link energy source is used in UPQC. The overall UPQC effectiveness is observed in mitigating power quality problems is observed in Matlab/Simulink.

Utilization of Unified Power Quality Conditioner for voltage sag/swell mitigation in microgrid

Microgrids (MG) are becoming increasingly attractive to consumers and a great number of them will be installed at consumers sites in the future. Due to high penetration of distributed generation (DG) units with different types of loads, microgrids can cause power quality and power control issues. Some of them are voltage stability, swells and sags, and power factor improvement which require reactive power. Microgrid particularly when operated in islanded operating condition has to maintain the power balance independently of a main grid due to tightly coupled generation, consumption and lack of infinite bus. Even in grid connected mode reactive power compensation is still challenging due to linear and nonlinear loads. In this regard, new techniques and devices for VAR compensation in the micro grid are being investigated. Among these custom power devices are proving to be a powerful solution to power quality problems. Hence the key objective of this paper is to investigate reactive power compensation in microgrids by means of custom power device. The device considered is Unified Power Quality Conditioner (UPQC). This custom power device is initially modeled, simulated and tested in conventional distribution power system. Later the same is incorporated into the microgrid. The microgrid is developed with two DG units, a PV cell and a wind generator to give an output voltage equal to the conventional 3 phase 4 wire distribution system. The performance of the custom power device with its control technique in providing the reactive power compensation to resolve the power quality issues in microgrid with dynamically varying load is examined. A comparison is made between the conventional distribution system and microgrid in terms of compensation using custom power device.

Performance analysis of voltage regulated inverter for FLC based PV-wind hybrid power system with real time data

The sun and wind based generation are well-thoroughly considered to be alternate source of green power generation which can mitigate the power demand issues. As sun powered and wind power advancements are entrenched and the infiltration of these Renewable Energy Sources (RES) into to network is expanding dynamically, testing errand is to keep up the voltage and frequency of the power generated from RES consistent as they specifically relies upon environmental conditions. So as to outline a legitimate control and to harness power from RES the learning of natural conditions for a specific area is fundamental. With this fundamental information of the environmental conditions, a suitable Photovoltaic and Wind power generations can be chosen to extract maximum power from the conditions. Fuzzy Logic Controller (FLC) based Maximum Power Point Tracking (MPPT) controlled boost converter are utilized for viable operation and to keep DC voltage steady at desired level. The control scheme of the inverter is intended to keep the load voltage and frequency of the AC supply at constant level regardless of progress in natural conditions and burden. A Simulink model of the proposed Hybrid system with the MPPT controlled Boost converters and Voltage regulated Inverter for stand-alone application is developed in MATLAB R2015a, Version 8.5.0. The ongoing information of Wind Speed and Solar Irradiation levels are recorded at BITS-Pilani, Hyderabad Campus utilizing climate observing framework introduced at the area the performance of the voltage regulated inverter under constant and varying linear, non-linear AC load with the real time data of the solar irradiation and wind speed as input is analyzed. The investigation shows that the magnitude of load voltage and frequency of the load voltage is maintained at desired level by the proposed inverter control logic.

A comparative analysis of Load Frequency Control Strategy of a Voltage Source Inverter for a stand-alone PV-Wind hybrid system

This paper presents a comparative analysis of the Load Frequency Control (LFC) strategies for a stand-alone PV-Wind hybrid system employed for voltage source inverter, with the PLL based and droop characteristics based control strategy. In the LFC strategies a discrete Phase lock Loop (PLL) based control technique is utilized to maintain the output voltage and frequency constant irrespective of change in load condition. In droop characteristics based control technique the frequency, voltage of the system is controlled by implementing droop characteristics of the PV and Wind generation. A MATLAB, Simulink based PV-Wind hybrid generation system is developed and the load frequency control strategies are implemented and simulated in the Simulink environment. Both the control strategies are tested for different loading conditions and the output voltage, frequency, of the PV-Wind hybrid power system are analyzed. The simulation results shows that the droop characteristics based strategy has enhanced control over the voltage regulated control scheme in terms of better output frequency response, voltage control and power flow control.

Fuzzy logic based control for IPFC for damping low frequency oscillations in multimachine power system

Mitigation of power system oscillations, within the frequency range of 0.1 to 2 Hz, is the problem of concern in the power industry as these oscillations, when exhibiting poor damping; affect the transmission line power transfer capability and power system stability. These low frequency oscillations greatly restrict power system operations and, in some cases, can also lead to widespread system disturbances. In this context, the Flexible AC Transmission System (FACTS) device, Interline Power Flow Controller (IPFC) employed to improve the transmission capability can be additionally utilized for damping control of power system oscillations. A fuzzy logic based IPFC damping controller is designed and compared with conventional damping controller to mitigate the low frequency oscillations for the mulitmachine power system. Case studies on three-machine nine-bus (IEEE WSCC) mulitmachine power system have been carried out in Matlab Simulink. The nonlinear simulation studies of the investigations conducted on the Multi-machine power systems installed with IPFC demonstrate that the control designs are effective in damping the power system oscillations.

Reactive power compensation in microgrids using custom power devices

Microgrids (MG) are becoming increasingly attractive to consumers and a great number of them will be installed at consumers sites in the future. Due to high penetration of distributed generation (DG) units with different types of loads, microgrids can cause power quality and power control issues. Some of them are voltage stability, swells and sags, and power factor improvement which require reactive power. Microgrid particularly when operated in islanded operating condition has to maintain the power balance independently of a main grid due to tightly coupled generation, consumption and lack of infinite bus. Even in grid connected mode reactive power compensation is still challenging due to linear and nonlinear loads. In this regard, new techniques and devices for VAR compensation in the micro grid are being investigated. Among these custom power devices are proving to be a powerful solution to power quality problems. Hence the main objective of this paper is to investigate reactive power compensation in microgrids using custom power devices. The devices considered are Dynamic Voltage Restorer (DVR), and Unified Power Quality Conditioner (UPQC). These custom power devices are initially modeled, simulated and tested in conventional distribution power system. Later these devices are incorporated into the microgrid. The microgrid is developed with two DG units, a PV cell and a wind generator to give an output voltage equal to the conventional 3phase 4 wire distribution system. The performance of the custom power devices with their respective control techniques in providing the reactive power compensation to resolve the power quality issues in microgrid with dynamically varying load is examined. A comparison is made between the conventional distribution system and microgrid in terms of compensation using custom power devices.