DETERMINATION OF OPTIMUM PENETRATION LEVEL IN THE DISTRIBUTED GENERATION INTEGRATED POWER SYSTEMS

Bu çalışmada, dağıtılmış enerji üretim tesisleri (DEÜ) entegre edilmiş elektrik şebekelerinin daha güvenilir çalıştırılabilmesine ve yönetilebilmesine yardımcı olması noktasında bazı kurallar geliştirilebilmesi amacıyla üç farklı şebeke üzerinde farklı sayıdaki DEÜ tesislerinin optimum katılım oranlarının (KO) ve bağlanma noktalarının belirlenmesine yönelik analizler yapılmıştır. DEÜ entegre edilmiş şebekelerin detaylı bir analizi yapılmaksızın şebekeye rastgele dahil edilmesi şebekenin güvenilirliğinin ve veriminin azalmasına neden olabilmektedir. DEÜ konsepti her ne kadar şebeke kayıplarında azalma ve gerilim profillerinde iyileştirmeye yardımcı olsa da, mevcut iletim hatlarının kapasiteleri bazı KO seviyelerinde yetersiz kalabilmektedir. Bu nedenle, bu çalışmada şebeke kayıpları ve gerilimlerin yanı sıra mevcut hat kapasiteleri de analizlerde dikkate alınmıştır. Bu bağlamda, tek ve birden fazla DEÜ bağlantılarında bir eşik KO değerinin olup olmadığı araştırılmıştır. Optimizasyon sonuçları neticesinde, şebeke planlaması açısından bazı temel kuralların elde edilmesi amacıyla şebeke kayıpları minimize edilirken gerilim profili ve hat akışları IEEE test şebekeleri üzerinde gözlemlenmiştir. In this study, the optimization of the penetration level and allocation of distributed generation (DG) in single- and multiple- DG concepts are investigated on three typical test networks in order to obtain more reliable DG-integrated power system and develop some rules to be used at network management centers. An improper integration of DG units, without detailed analysis, decreases the reliability and efficiency of power networks. Although DGs can decrease power loss and improve voltage profile, they can cause the congestion on transmission lines at some penetration levels. For this reason, line flows are also considered besides power loss and voltage profile in this paper. In this manner, a threshold penetration level is investigated by considering both single- and multiple- DG concepts. According to the results of optimization, voltage profiles and line flows are observed on the IEEE test networks while minimizing power loss in order to reveal some rules in terms of power system plannin

An Insight into the Impact of Solar and Wind Powers' Probability Distributions on Distribution Network Investments

With the introduction of renewable generators, the investment challenges have also increased recently because of the associated stochastic behaviors. Their impacts in terms of the investment related to the distribution network could be different depending on the probability distribution of the corresponding renewable generators, historical data modeling, and network structure. Therefore, the impacts of the probability distributions of wind power plants (WP Ps) and solar power plants (SPPs) are analyzed thoroughly for different case studies by using a convolution based distribution network planning (DNP) model. The following six cases are considered: the 1) integration of only WPPs considering one scenario of load, wind, and solar powers, 2) integration of only WPPs considering four scenarios, 3) integration of only SPPs considering one scenario, 4) integration of only SP Ps considering four scenarios, 5) integration of both WPPs and SPPs considering one scenario, and 6) integration of both WPPs and SPPs considering four scenarios. The results show that considering the four scenarios is more suitable for a risk averse approach planning, as the chance constraints are formulated separately for all the scenarios. However, the probability distribution of a different generation technology exerts a significant impact on the investment results of DNP

Analysis of renewable generation's integration using multi-objective fashion for multistage distribution network expansion planning

In this paper, the integration of intermittent distributed generation (wind and solar) is dealt with by proposing a multi-objective multistage distribution network expansion planning formulation based on epsilon-constraint method. This approach allows the planners to obtain pareto-optimal solutions based on the two objective functions: (1) installation costs of distributed generation, substations, feeders, maintenance costs of assets, costs of energy purchased from substations, cost of unserved energy and (2) utilization of renewable distributed generation. To represent the intermittent nature of load and renewable distributed generation, several time blocks are utilized, and its effectiveness is compared with an existing approach. The overall problem is formulated as a mixed-integer linear programming and a linear equation-based substation price is utilized within the optimization framework to reduce the size of the problem. The proposed method is applied to the modified 24-nodes test network for different cases to analyse the utilization of renewable distributed generation from different point of views and it is inferred from the results that the proposed model yields a variety of planning solutions which are better to increase the utilization of renewable distributed generation

Coordinated TCSC Allocation and Network Reinforcements Planning With Wind Power

Integration of wind power plants into power systems requires special attention on network planning to reduce curtailed wind energy as well as investment costs and generation costs. To this aim, in this study, transmission expansion planning, reactive power planning, and the allocation of TCSC devices are coordinated in order to minimize investment costs of transmission lines, reactive power sources, and TCSC devices along with the sum of generation costs and penalty for load curtailment. Installed wind power plants are modeled by using load-wind scenarios, which are obtained by clustering procedure. They are integrated into the constraints of the proposed method via linearized ac power flow equations. This assures keeping the proposed method as mixed-integer linear programming problem. The proposed method is applied to the Garver 6-bus and IEEE 24-bus RTS test systems under different case studies. Results prove the contributions of the coordinated network planning

Transmission Expansion Planning for Wind Turbine Integrated Power Systems Considering Contingencies

IEEE International Symposium on Innovations in Intelligent Systems and Applications (INISTA) -- JUN 23-25, 2014 -- Alberobello, ITALYWOS: 000346665300052Increasing penetration level of wind turbines in power systems reveal new challenges for the power system planners. Transmission expansion planning is one of the most important planning problems to maintain secure and reliable operation of power systems. In this study, a new transmission expansion planning methodology considering N-1 contingency conditions is proposed to find the location of new transmission lines while minimizing investment cost and curtailed wind energy. To deal with the uncertainty of load and output power of wind turbines, fuzzy clustering based probabilistic method is used for determination of load and wind scenarios. Proposed methodology uses the DC-power flow equations based optimal power flow and integer genetic algorithm to determine the locations of new assets and it is applied to the modified IEEE 24-bus test system.IEEE, IEEE Italy Sec