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Power and Energy Society General Meeting (PES), 2013 IEEE

Date 21-25 July 2013

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Displaying Results 1 - 25 of 935
  • Development and planning of solar power in China

    Publication Year: 2013 , Page(s): 1 - 5
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (753 KB) |  | HTML iconHTML  

    Solar energy is becoming the third most important renewable source in terms of globally installed capacity, after hydro and wind power. China is experiencing a rapid expansion in the solar power industry. This paper provides a good overview of the current status and future development of solar generation in China. This paper discusses medium and long-term planning goals of solar power in China including interconnection and grid planning challenges. Interconnection rules, government regulations, financial incentive and subsidy programs, tariffs and tax issues with regards to solar power development are also discussed. Specific numbers are given with regards to nationwide installed solar power capacity at the present and in the future. The paper shares the Chinese solar power development experience with the world solar power industry and contributes to the area of generation mix strategies, planning and interconnection. View full abstract»

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  • Towards a 3-level blackout probabilistic risk assessment: Achievements and challenges

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (466 KB) |  | HTML iconHTML  

    Although blackouts are infrequent, they result in major societal and economical negative consequences. These massive disruptions to electricity service are due to cascading outages, in which a lot of different phenomena occur. Even if a variety of methods are emerging to study cascading outages, it remains difficult to estimate the risk of blackout for a real grid and dangerous scenarios. Based on the analysis of past blackouts, a 3-level blackout probabilistic risk assessment can be developed in order to consider the main phenomena occurring in a cascading failure in a realistic way. But such an approach encounters several challenges and difficulties. The aim of this paper is to present such an approach, to assess present achievements and to discuss ways of solving future challenges. View full abstract»

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  • Reliability-constrained optimal sizing of energy storage system in a microgrid shaghayegh bahramirad

    Publication Year: 2013 , Page(s): 1
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (55 KB) |  | HTML iconHTML  

    Summary form only given. This paper presents a model for calculating the optimal size of an energy storage system (ESS) in a microgrid considering reliability criterion. The optimal ESS sizing problem minimizes the investment cost of the ESS, as well as expected microgrid operating cost. By increasing the ESS size the investment cost linearly increases while the operating cost exponentially reduces. Also a larger ESS size increases the reliability of the microgrid. Therefore, the objective would be to find the optimal ESS size in which the summation of ESS investment cost and microgrid operating cost is minimized and the reliability criterion is satisfied. A practical model for ESS is utilized. Mixed-integer programming (MIP) is utilized to formulate the problem. Illustrative examples are presented to show the efficiency of the proposed method. View full abstract»

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  • Constrained potential function-based control of microgrids for improved dynamic performance

    Publication Year: 2013 , Page(s): 1
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (53 KB)  

    Summary form only given. In the context of the smart grid, this paper focuses on control and management strategies for integration of distributed energy resources in the power system. This work conceptualizes a hierarchical framework for the control of microgrids-the building blocks of the smart grid-and develops the notion of potential functions for the secondary controller for devising intermediate set points to ensure feasibility of operation. A potential function is defined for each controllable unit of the microgrid such that minimizing the potential function corresponds to achieving the control goal. The set points are dynamically updated using communication within the microgrid. This strategy is generalized to include both local and system-wide constraints. Case studies are presented that show effectiveness of the proposed approach in stabilizing a microgrid in response to disturbances such as load change, line outage, and generator malfunctioning. View full abstract»

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  • Cross-border power trading in South Asia: Modelling analysis to assess economic benefits

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (165 KB) |  | HTML iconHTML  

    There has been an unprecedented growth in electricity demand in South Asian countries in the last decade - most notably in India. There are significant economic and reliability benefits of power trading on a regional basis among the South Asian countries that largely remain unexploited to date. For instance, large scale power trading between India and Nepal/Bhutan can unleash massive hydro potential in excess of 100 GW that could be the key to reducing fuel costs, unserved energy and CO2 emissions throughout South Asia. This study is one of the first attempts to put in context how significant these benefits can be even in the short term. We have undertaken a modeling study that includes load flow analysis, transmission constrained investment and dispatch optimization and Monte Carlo simulation of unserved energy, to assess these benefits. We have estimated annual benefits for the year 2016/17 which shows economic and reliability benefits for a single year may justify the entire investment needed in the interconnection infrastructure. If we consider the significant environmental benefits in terms of CO2 reduction, total benefits would further outweigh the costs. View full abstract»

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  • Generator thermal stress during a Geomagnetic Disturbance

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (310 KB) |  | HTML iconHTML  

    This paper investigates the operating condition of the generator during a Geomagnetic Disturbance (GMD). Generators are sensitive to harmonics and negative sequence currents, caused by the half-cycle saturation of the generator step-up transformer due to Geomagnetically Induced Current. Such harmonic currents can cause rotor heating, alarming, and the loss of generation. Based on the time-domain simulation in the EMTP, this study investigates the order and magnitude of the harmonics which impact the generator, and determines the rotor heating level due to such harmonics, at various levels of the GIC. The study reveals that the generator can reach its thermal capability limit at moderate GIC levels. However, the existing standards, e.g., IEEE Standards C50.12 and C50.13, fail to account for such operating conditions, and the corresponding recommendations underestimate the rotor heating level. As such, the negative sequence relays may not accurately operate under GMDs. A modification to the standards is also required which is proposed in this study. View full abstract»

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  • A probabilistic load modelling approach using clustering algorithms

    Publication Year: 2013 , Page(s): 1 - 5
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (106 KB) |  | HTML iconHTML  

    In this paper, a novel probabilistic load modeling approach is presented. The proposed approach starts by grouping the 24 data points representing the hourly loading of each day in one data segment. The resulting 365 data segments representing the whole year loading profile are evaluated for similarities using principle component analysis; then segments with similar principal components are grouped together into one cluster using clustering algorithms. For each cluster a representative segment is selected and its probability of occurrence is computed. The results of the proposed algorithm can be used in different studies to model the long term behavior of electrical loads taking into account their temporal variations. This feature is possible as the selected representative segments cover the whole year. The designated representative segments are assigned probabilistic indices that correspond to their frequency of occurrence, thus preserving the stochastic nature of electrical loads. View full abstract»

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  • Impact of high PV penetration on distribution transformer life time

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (290 KB) |  | HTML iconHTML  

    Integration of rooftop photovoltaics (PVs) in residential networks at moderate penetration levels is becoming a reality in many countries including Australia. Despite the technical challenges in properly accommodating PV units, one of the major benefits is the ability of PV units to extend useful life time of distribution transformers. This effect is not quantified in the existing literature. This paper carries out an analysis into the impacts of rooftop PVs at different penetration levels on the performance of distribution transformers and residential networks. This paper presents a methodology to quantify the benefit of the distribution transformer life extension brought about by customer-owned rooftop PV units. The proposed methodology is applied to a real distribution system with various scenarios, including different penetration levels. The results show the distribution transformer loss-of-life function, as a function of the rooftop PV penetration level, is monotonically decreasing function which saturates after a certain penetration level. The best life improvements occur with transformers that are highly loaded and the presence of a significant PV installation may support the deferral of transformer upgrades. View full abstract»

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  • Bayesian neural network and discrete wavelet transform for partial discharge pattern classification in high voltage equipment

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (486 KB) |  | HTML iconHTML  

    Partial discharge (PD) pattern recognition has been applied for identifying the types of insulation defects in high voltage (HV) equipment. This paper proposes a novel Bayesian neural network (BNN) and discrete wavelet transform (DWT) hybrid algorithm for PD pattern recognition. Laboratory experiments on a number of PD models have been conducted for evaluating the performance of the proposed algorithm. View full abstract»

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  • A practical improvement to stator ground fault protection using negative sequence current

    Publication Year: 2013 , Page(s): 1 - 4
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (145 KB) |  | HTML iconHTML  

    This paper discusses the phenomenon of zero sequence voltage coupling from the high-voltage system to the high-impedance grounded low-voltage bus for a synchronous generator and a simple improvement to accelerate stator ground fault protection (59G) using negative sequence current. View full abstract»

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  • Fast frequency and phase estimation in three phase power systems

    Publication Year: 2013 , Page(s): 1 - 5
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (237 KB) |  | HTML iconHTML  

    In this paper, we investigate the fundamental frequency and phase estimation problem in a balanced three-phase power system with harmonic distortion. An estimation algorithm that can rapidly track the fast-changing frequency and phase by using quarter cycle samples are proposed. Specifically, the data model in the three-phase power system is first converted to the noise-corrupted single phase harmonic signal model by using the Clarke transformation. A new weighted least squares (WLS) parameter estimator, which refines the initial estimates from the standard estimation techniques, is computed by utilizing the harmonic structure of the signal. Since the initial estimates become unreliable with limited samples, we proposed an iterative algorithm to polish the initial estimates for WLS. Numerical results show that the proposed estimator outperforms the conventional estimators, especially in a data-limited case. View full abstract»

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  • Mitigation of transient overvoltages under lightning in networks with wind farms connection using MOV surge arresters

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (384 KB) |  | HTML iconHTML  

    The effectiveness of surge arresters to mitigate transient overvoltages in Wind power plant (WPP) located in areas with high lightning activity and high soil resistivity is investigated in this paper. WPP is dispersed over large areas of land with several hundred metres of overhead lines and underground cables. However, the insulations of the WPP components are exposed to severe overvoltage stress when lightning strikes the overhead lines and propagates through the WPP cable networks. These overvoltages can damage the surge arresters being used to protect WPP cable network and other components if the ground resistance is relatively high. The ground resistance can be reduced significantly in areas with high soil resistivity but at a high financial cost. EMTP was used to analyse the effects of lightning surge at different ground resistances at the WPP towers. The results show that the energy absorbed by the arresters increase with higher ground resistance. View full abstract»

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  • Electrification of remote villages in Assam (India): Issues and case studies

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (405 KB) |  | HTML iconHTML  

    Rural electrification in India has received considerable attention and funding lately. However, these efforts are often disorganized, and do not consider the full set of locally available resources. This study presents our analysis for Assam, a Northeastern state in India, which has more than 2000 (or, 25%) of un-electrified villages. Our site visits, discussions, research and analysis spanning over a year, show that it is possible to efficiently combine local resources and distribution network extension using SWER, to electrify many of these villages at a fraction of a cost of the current policy measures using solar home lighting systems. We also emphasise the need to customize the solution for different areas given the variation in local resources among other things. The sample projects we have selected are currently being considered for pilot projects, to be rolled out throughout the state and possibly other states. View full abstract»

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  • Bandwidth and latency requirements for smart transmission grid applications

    Publication Year: 2013 , Page(s): 1
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (58 KB)  

    The rapid increase of phasor measurements on the high voltage power system has opened opportunities for new applications to enhance the operation of the grid. To take advantage of the high sampling rates of these measurement data, these applications will require a high-bandwidth, networked communication system. The specifications for this next generation communication system that will overlay the continental power grids are under intense discussion at this time by organizations like the North-American Synchro-Phasor Initiative (NASPI). In this paper we present a method to simulate, design and test the adequacy of a communication system for a particular transmission grid. The main difference from typical communication system studies is that we formulate the communication requirements from the power grid application requirements, that is, the communication design, simulation and testing is from the viewpoint of the anticipated power applications. Themethod is demonstrated on a WECC 225 bus and a Polish 2383 bus transmission system models. View full abstract»

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  • Studies on operation parameters of SOFC-compressor combine system

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (784 KB) |  | HTML iconHTML  

    Previous work showed that pressurization has positive effect on the output power of SOFC. However, the compressor used to enhance the fuel cell operation pressure consumes electricity. The parasitic power cannot be ignored when calculating the net output power. In this paper, the influence of pressurization on the SOFC-compressor combine system was presented. The comprehensive SOFC steady-state model takes the effects of operation parameters and the microstructure of the fuel cell into consideration, based on which, the output performance of the fuel cell is evaluated. The fuel cell voltage-current steady-state relationship is proved that the model is accurate in predicting the SOFC performance under different pressures. The power consumption of the compressor is also obtained by fundamental thermodynamic principles. From the simulation results obtained by MATLAB, the relations between pressure and cell/system output power are observed and analyzed, which shows an optimization problem between the efficiency and the output power. View full abstract»

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  • Traveling-wave-based line fault location in star-connected multiterminal HVDC systems

    Publication Year: 2013 , Page(s): 1
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (57 KB)  

    Summary form only given. This paper presents a novel algorithm to determine the location of dc line faults in an HVDC system with multiple terminals connected to a common point, using only the measurements taken at the converter stations. The algorithm relies on the traveling-wave principle, and requires the fault-generated surge arrival times at the converter terminals. With accurate surge arrival times obtained from time-synchronized measurements, the proposed algorithm can accurately predict the faulty segment as well as the exact fault location. Continuous wavelet transform coefficients of the input signal are used to determine the precise time of arrival of traveling waves at the dc line terminals. Performance of the proposed fault-location scheme is analyzed through detailed simulations carried out using the electromagnetic transient simulation software PSCAD. The algorithm does not use reflected waves for its calculations and therefore it is more robust compared to fault location algorithms previously proposed for teed transmission lines. Furthermore, the algorithm can be generalized to handle any number of line segments connected to the star point. View full abstract»

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  • An approach to real time electricity marginal cost pricing calculation with impact factors and carbon emissions

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (972 KB) |  | HTML iconHTML  

    This approach aims to develop an algorithm for dealing with real time electricity price. The impact factors and cost of carbon dioxide emissions are contained in the calculation of electricity price. The derived theory is an initiative of green energy pricing mechanism in a power system. Standard IEEE-9 and 30-bus test systems and network branch data are put into practice to verify the model concepts. MATPOWER's dedicated open source Matlab-based program is the main substance for simulating AC optimal power flow. Marginal cost pricing and cost of marginal carbon emissions comprise the basic elements of electricity price. The uniform and location electricity price are calculated in the test systems separately. The results show this model is a very fast speed and accurate solution solvers of electricity price. Moreover, real time energy price with cost of carbon emissions makes users pay a little bit more for their electricity consumption. It is not only to have an attitude of seeking energy-saving, but even to achieve a basis structure of green energy pricing strategy. View full abstract»

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  • Planning of electric vehicle charging infrastructure

    Publication Year: 2013 , Page(s): 1 - 5
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (270 KB) |  | HTML iconHTML  

    The Electric Vehicle (EV) has become the sustainable alternative to fossil fuel driven automobiles. As a result, a new type of load is being seen on power systems. Hence, provision of an EV charging infrastructure has become a new challenge for power system engineers worldwide. It has been identified that the voltage dependent nature of EV load may lead to voltage instabilities in the system. Furthermore, significant load integration into the distribution system may overload the system components, increase power system losses and may violate system constraints. Despite these factors EV consumers should be provided with convenient and reliable charging facilities. Hence, the identification of a charging infrastructure which satisfies requirements of both the EV customer and the power system is of primary importance. A particle swarm optimization (PSO) based approach is considered here for planning of EV charging infrastructure. View full abstract»

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  • Joint improvement of system loadability and stability through a multi-stage planning of a UPFC with a PMU-based supplementary damping control

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (822 KB) |  | HTML iconHTML  

    One of the most important issues for power system security is to effectively damp the power system oscillations in order to enhance transient stability and improve dynamic performance. Traditionally, oscillations have been damped by Power System Stabilizer (PSS). In recent years, FACTS devices combined with a supplementary controller-known as a Power Oscillation Damper (POD)-have been also used to damp low-frequency oscillations in power systems. In this paper, a multi-step plan is developed to implement a Wide-Area Power Oscillation Damping (WA-POD) controller of a UPFC in 14-bus test system. The first step of this plan is to find the optimal location for the UPFC to maximize power system loadability; the second step is to estimate the dynamic states of the synchronous generators; and the third step is to implement the WA-POD controller using the states estimated in step two. The estimated rotor angles are used to provide the input signal of the WA-POD controller while the estimated rotor speed deviations will be used for an off-line parameter tuning of both PSS and WA-POD using the genetic algorithm. Different types of faults are applied to the network to compare the performance of the traditional PSS and the WA-POD controller in the 14-bus test system. Simulation results show the effectiveness of the implemented WA-POD controller in damping low-frequency oscillations and improving the dynamic performance of the system. View full abstract»

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  • Power system overvoltage detection based on a morphological filtering algorithm

    Publication Year: 2013 , Page(s): 1 - 4
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (582 KB) |  | HTML iconHTML  

    The fast development of electronics and the use of diverse electronic based materials have brought with themselves many new aspects of challenges to be faced by electric power providers. Overvoltages as the main cause of damages and accidents in power distribution networks represent the important aspect that is being studied in order to provide better energy to consumers giving the double advantage of preserving and reducing accidents in both the energy user and the provider sides. The work presented in this paper is one step of the overvoltage detection system to be designed by the authors. Several cases of overvoltages have been studied and simulated on ATP-EMTP software to help adjusting choices of the most suitable morphological filtering algorithm to perform the detection part of the future online overvoltages monitoring system. The authors have focussed on the overvoltage time and frequency research results to make the assertions on overvoltages waveforms processing based on mathematical morphology theory. Experiments related to different overvoltages types and amplitudes have helped to parameterize the most suitable detection algorithm. Simulation results done with MATLAB show the efficiency of the morphological gradient detection algorithm specialized for power system overvoltage detection. View full abstract»

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  • A study on rotor surface lossesa in small-to-medium cylindrical synchronous machine

    Publication Year: 2013 , Page(s): 1
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (21 KB) |  | HTML iconHTML  

    Summary form only given. This paper presents a new method for estimation of rotor surface losses in small to medium capacity synchronous machines. In this study, the authors have proposed a method for estimating the slot ripple losses induced on the rotor surface. Also, we compared the damper systems using the Finite Element Method (FEM) and verified the results by the measured data. View full abstract»

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  • Hierarchical risk assessment of transmission network considering the influence of micro-grid

    Publication Year: 2013 , Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (429 KB) |  | HTML iconHTML  

    Transmission network risk is calculated by multiplying occurrence probability and consequence of contingencies. Since power flow in the traditional distribution system is unidirectional, its loads are usually aggregated into an equal load and connected to the transmission network through a substation in the traditional risk assessment. And, all loads are simply treated as constant-power type. Details of distribution network and loads are usually ignored. However, today a growing number of distributed generators (DGs) based on renewable resources being connected to modern power systems. How to properly evaluate their influence on risk assessment of transmission network should be considered. Micro-grid has been regarded as a good way to integrate various renewable resources into distribution network. It can increase DG's penetration and reduce its negative impact. However, micro-grid can be considered as a controllable load or a small virtual power plant, so it can significantly change characteristics of distribution loads and operational modes of distribution network. In this paper, micro-grid is used as a tool to reduce load curtailment under some critical contingencies. And its influence on risk assessment of transmission network is then analyzed and discussed. In the study, a linear optimization method is used to determine the load curtailment. Discrete probability model of DGs in micro-grid and detailed model of distribution system are taken into account in the optimal process, such as island, tie switches, links, etc. Risk calculation of whole power system is executed though iterations between transmission network and distribution system. Load curtailment expectation instead of absolute load curtailment is used to risk calculation. The correctness and effectiveness of the proposed method is finally validated by RTS and RBTS test system. View full abstract»

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  • Dynamic performance analysis of potential current control strategies for grid connected applications

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (324 KB) |  | HTML iconHTML  

    Environmental concerns were raised due to the recent demand increase for energy which resulted in higher CO2 emissions. Hence, it became essential to research a different energy source to meet the increasing demand. Since Photovoltaics (PV) were found to be a promising source, the governments started to support grid connected PV projects. However, grid connected PV systems cause many stability issues. Therefore, controlling methods must be implemented. Several control techniques have been proposed for grid connected applications in the last few decades. The controllers attempt to achieve stability, low harmonic content and fast dynamic response. However, tradeoffs are usually required. In order to understand the potential developments in this field, the paper will present three different current control strategies used in grid connected systems, compare them and recommend the usage of the most suitable. This was achieved by developing a MATLAB/Simulink model of a photovoltaic grid connected system in order to simulate case studies that tests Voltage Oriented Current Control (VOC), Direct Power Control (DPC), and PQ Synchronous Control (PQSC) topologies under different scenarios. The model configuration used ensures realistic simulation conditions in order to study the controllers thoroughly. Case studies are simulated in order to investigate the three controllers' stability and dynamic response under variable irradiance, Single Line to Ground (SLG) fault and three phase fault. Such case studies results can act as benchmarks that can be used by other researchers to compare their controller's performance against a standard system and check for improvements. View full abstract»

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  • Power system overvoltage identification using feedforward neural network

    Publication Year: 2013 , Page(s): 1 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (531 KB) |  | HTML iconHTML  

    The main causes of electrical accidents in power distribution networks are internal and external overvoltages. In this paper, the authors introduce an intelligent way of identifying internal and external overvoltages based on time domain studies of their waveforms. Seven parameters are extracted from the signal to build a sample vector as entry data for every sampled overvoltage to be identified. A neural network based on feedforward multilayer perceptron topology is used for the identification and classification. The overvoltage samples used in this work are obtained from ATP-EMTP software and the data extraction is performed with a script written in Matlab. A variety of power system overvoltages have been used to test the validity of the proposed method and we obtained an result of 98.82% of positive identification and classification. Results prove that, the feedforward multilayer perceptron is a suitable candidate in power system overvoltage identification and classification. View full abstract»

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  • Improved low voltage grid-integration of photovoltaic systems in Germany

    Publication Year: 2013 , Page(s): 1
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (54 KB)  

    Abstract form only given. This work discusses the technical and economical benefits of different active and reactive power control strategies for grid-connected photovoltaic systems in Germany. The aim of these control strategies is to limit the voltage rise, caused by a high local photovoltaic power feed-in and hence allow additional photovoltaic capacity to be connected to the mains. Autonomous inverter control strategies, which do not require any kind of data communication between the inverter and its environment, as well as an on-load tap changer for distribution transformers is investigated. The technical and economical assessment of these strategies is derived from 12 month RMS simulations, which are based on a real low voltage grid and measured DC power generation values. The results show that the provision of reactive power is an especially effective way to increase the hosting capacity of a low voltage grid for photovoltaic systems. View full abstract»

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