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Load Compensation by Diesel Generator and Three Level Inverter Based DSTATCOM
Mr. K. Murali
International Journal of Engineering Trends and Technology , 2012,
Abstract: This paper presents the load compensation by diesel generator. In this compensation reactive power, harmonics and unbalanced load current generates because of linear or nonlinear loads. The control of Distribution Static Synchronous Compensator (DSTATCOM) is used for reactive power, harmonics and unbalanced load current compensation. Proportional – Integral (PI) controller is used to maintain a constant voltage at the dc – bus of a voltage – source converter (VSC) working as a DSTATCOM. Switching of ThreeLevel VSC is achieved by controlling load current using Sinusoidal Pulse Width Modulation (SPWM) control. This scheme is simulated under MATLAB environment using simulink toolboxes for feeding linear and nonlinear loads. The modeling is performed for a three – phase, three – wire star – connected synchronous generator coupled to a diesel engine, along with the three level inverter based VSC working as a DSTATCOM.
Dynamic Modeling of Autonomous Wind–Diesel system with Fixed-Speed Wind Turbine  [cached]
Farshad Dastyar,Hamidreza Najafi
International Journal of Applied Power Engineering , 2012, DOI: 10.11591/ijape.v1i2.764
Abstract: Wind turbines have often connected to small power systems, operating in parallel to diesel generators, as is typically the case in autonomous wind–diesel installations or small island systems with high wind potential. Hence, the modeling and analysis of the dynamic behavior of wind–diesel power systems in presence of wind power will be important. In this paper, the system under study is modeled by a set of dynamic and algebraic equations (DAE). Dynamic behavior of a wind-diesel system is investigated by the proposed dynamic model. Wind-diesel system consists of wind turbines that are connected to synchronous diesel generator via short transmission line with local load. Dynamic stability of autonomous wind–diesel systems are discussed with emphasis on the eigenvalue analysis and the effective parameters on system stability. In this regards, saddle node bifurcation and hopf bifurcation are also investigated.
Economic Efficiency Assessment of Autonomous Wind/Diesel/Hydrogen Systems in Russia  [PDF]
O. V. Marchenko,S. V. Solomin
Journal of Renewable Energy , 2013, DOI: 10.1155/2013/101972
Abstract: The economic efficiency of harnessing wind energy in the autonomous power systems of Russia is analyzed. Wind turbines are shown to be competitive for many considered variants (groups of consumers, placement areas, and climatic and meteorological conditions). The authors study the possibility of storing energy in the form of hydrogen in the autonomous wind/diesel/hydrogen power systems that include wind turbines, diesel generator, electrolyzer, hydrogen tank, and fuel cells. The paper presents the zones of economic efficiency of the system (set of parameters that provide its competitiveness) depending on load, fuel price, and long-term average annual wind speed. At low wind speed and low price of fuel, it is reasonable to use only diesel generator to supply power to consumers. When the fuel price and wind speed increase, first it becomes more economical to use a wind-diesel system and then wind turbines with a hydrogen system. In the latter case, according to the optimization results, diesel generator is excluded from the system. 1. Introduction In the recent years, the energy policy of many countries has been aimed at increasing the share of renewable energy sources (RES) in the total energy production. In Russia, the share of RES (without large hydropower plants) in the electricity production does not exceed 1%. However, the “Energy Strategy of Russia for the period up to 2030” (approved by the Russian Government) suggests that, in 20 years, this share may increase up to 4.5%. Providing a substantial environmental effect (decrease in the emissions from energy sector), RES can often be economically efficient and competitive with the energy sources based on fossil fuel [1–7]. It is expected that, in the nearest and, moreover, distant future, the role of RES in Russian and world energy industry will essentially increase due to the improvement of characteristics and a projected rise in the fossil fuel price [8–12]. It is reasonable to use RES primarily in small autonomous (decentralized) power systems located in remote hard-to-reach areas, where the price of imported fossil fuel is very high. Russian zones of decentralized power supply that do not have any modern electrical networks and large energy sources occupy about 70% of the country and are situated mostly in the Far North. The Far North is represented by a number of regions in the European part of the country (Murmansk and Arkhangelsk regions, the Republic of Karelia, and the Republic of Komi), Siberia (the north of Tyumen Region and Krasnoyarsk Territory), and the Far East (Yakutia, Chukotka,
Control and Modeling of Shaft Generator with PWM Voltage Source Inverter for ship  [PDF]
Sathish Kumar T,Gowrishankar J
International Journal of Soft Computing & Engineering , 2012,
Abstract: This papers deals with well – based mathematicalmodeling of variable speed alternator (Shaft Generator) withPWM voltage source inverter used in ship. Detailed knowledge ofelectromagnetic characteristics of shaft generator is necessary fordesign complex ship's power system. Such knowledge isobtainable only by numerical simulations. The dynamic behaviorof shaft generators, SPWM voltage source inverter and theircontrollers during load variations are also discussed with the helpof MATLAB/SIMULINK. Elimination of harmonic contentsusing sinusoidal pulse width modulation also discussed here.
The Numerical Modeling of Transient Regimes of Diesel Generator Sets
Tiberiu Tudorache,Cristian Roman
Acta Polytechnica Hungarica , 2010,
Abstract: This paper deals with the numerical modeling of a diesel generator set used as amain energy source in isolated areas and as a back-up energy source in the case ofrenewable energy systems. The numerical models are developed using a Matlab/Simulinksoftware package and they prove to be a powerful tool for the computer aided design ofcomplex hybrid power systems. Several operation regimes of the equipment are studied.The numerical study is completed with experimental measurements on a Kipor type dieselelectricgenerator set.
Virtual Synchronous Generator: A Control Strategy to Improve Dynamic Frequency Control in Autonomous Power Systems  [PDF]
Miguel Torres, Luiz A. C. Lopes
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.52A005
Abstract:

Ideally, diesel hybrid autonomous power systems would operate with high penetration of renewable energy sources such as wind and photovoltaic to minimize fuel consumption. However, since these are inherently intermittent and fluctuating, the grid-forming diesel engine generator sets are usually required to operate with larger amounts of spinning reserve, often at low loading conditions what tends to increases operating and maintenance costs. Frequency stability is of great concern in “small” systems, such as mini-grids, where any individual generator in-feed represents a substantial portion of the total demand. There, the initial rate of change of frequency is typically larger and a lower value of frequency can be reached in a shorter time than in conventional systems with all generation supplied by rotating machines, possibly resulting in under-frequency load shedding and tripping of renewable energy generators. The first part of this paper, discusses some general concepts regarding frequency stability in a diesel hybrid mini-grid and how energy storage systems can be used to enhance system performance. Then, a particular technique based on a virtual synchronous generator is presented and its effectiveness is demonstrated with simulation results.

Prospects of Wind-Diesel Generator-Battery Hybrid Power System: A Feasibility Study in Algeria  [PDF]
Djohra Saheb-Koussa,Mustapha Koussa,Nourredine Said
Journal of Wind Energy , 2013, DOI: 10.1155/2013/413425
Abstract: The present work analyses the feasibility of a wind-diesel generator-battery hybrid system. The wind energy resource data are collected from the weather station at the Renewable Energy Development Center of Bouzareah in Algeria. The recorded values vary from 5.5?m/s to 7?m/s at 25?m. The hybrid system analysis has shown that for a household consuming 1,270?kWh/yr, the cost of energy is 1.205?USD/kWh and produces 2,493?kWh/yr in which 93% of electricity comes from wind energy. From this study, it is clear that the optimized hybrid system is more cost effective compared to the diesel generator system alone where the NPC and COE are equal, respectively, to 19,561?USD and 1.205?USD/kWh and 47,932?USD and 2.952?USD/kWh. The sensitivity analysis predicts that the grid extension distance varies from 1.25 to 1.85?km depending on wind speed and fuel price which indicate a positive result to implement a stand-alone hybrid power system as an alternative to grid extension. In addition to the feasibility of this system, it can reduce the emission of the CO2, SO2, and NOx, respectively, from 4758 to 147, from 9.45 to 0.294, and from 105 to 3.23?kg/yr. Investments in autonomous renewable energy systems should be considered particularly in remote areas. They can be financed in the framework of the National Energy Action Plan of Algeria. 1. Introduction An important challenge for Algeria to take up is the implementation of health care services in isolated coastal and mountainous regions of the north, high plains, and desert regions of the south. Communities living there lack electricity for water sterilization, domestic use, medical services, education, and irrigation. These remote areas are not supplied with power lines. The important infant and maternal mortality rate in these regions is due essentially to transmissible diseases, scorpion poisoning, and malnutrition. The sub-Saharan localities are also threatened by the extension of sexually transmissible diseases as discussed by Armini [1]. The constructions of health clinics electrified by local resources such as solar and wind energy become the most suitable alternative. In this context the aim of the present study is to control the feasibility, analyze, and simulate a wind-diesel generator-battery hybrid system. Many research works including feasibility, optimization, and simulation studies have been carried out on hybrid energy systems [2–4]. Khelif et al. [2] have undertaken a feasibility of a hybrid PV/Battery/Diesel power plant using real meteorological data equipment costs to show the possibility of modifying
Some results concerning no-storage wind-diesel systems control
Ciprian VLAD,Nicolaos Antonio CUTULULIS,Julie LEFEBVRE,Emil CEANGA
Annals of Dunarea de Jos , 2006,
Abstract: This paper deal with the dynamics of an autonomous no storage wind-diesel system, comprising a diesel generator and a controlled wind system with a hypo/hyper synchronous cascade. The objective is to maximize the wind energy penetration rate, by an optimization control system, respecting the quality standard concerning the frequency deviation in the AC local grid. Also, the influence of the diesel drive train on the system’s dynamics performances is discussed.
The Control and Modeling of Diesel Generator Set in Electric Propulsion Ship  [cached]
Le Luo,Lan Gao,Hehe Fu
International Journal of Information Technology and Computer Science , 2011,
Abstract: This paper analyzes the characteristics of power system on electric propulsion ship. The mathematical model and simulation model of diesel engine PID speed control system and synchronous generator’s AVR+PSS excitation control system was built. At last the simulation test of suddenly add load was did in MATLAB/simulink environment. The result shows that the speed control and excitation control system has well stability, rapidity and some robustness.
Performance analysis of voltage regulation in diesel-wind generation
S Shashikant, SK Srivastava
International Journal of Engineering, Science and Technology , 2011,
Abstract: In presented paper performance analysis of the hybrid diesel-wind energy conversion system has presented. Electrical energy is generated by the two sources one source is the diesel engine generator and the other source is the wind energy conversion system the supply is provided to the isolated load. The voltage is regulated at the load side .The electrical energy produced by the wind turbine at constant speed is connected to the specific load by the rectifier, d.c link and pulse width modulation inverter. In this work the value are assumed in the IS system. Voltage regulation is done with the use of PI controller and simulation results are performed on the MATLAB (new version).
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