Maximum Penetration Level Of Distributed Generation Research Articles

Increasing Distributed Generation Penetration Using Network Reconfiguration and Soft Open Points

High penetration levels of distributed generation (DG) become new challenges for traditional electrical distribution networks. The increase of DG penetration can be facilitated by means of Network Reconfiguration (NR) and Soft Open Point (SOP). SOP is a power electronic device installed between adjacent feeders of a distribution network, with the capability to control real and reactive power flows through its connecting points. This paper explores the maximum DG penetration level that distribution network can accommodate before violating any operational constraints using three approaches: NR, SOP, and a combined method using NR to coordinate with SOP operation. The impacts of DG concentrations and SOP locations on achievable DG penetration levels are analysed. The effectiveness of the proposed approaches and the significant benefits obtained by using the combination of NR and SOP are demonstrated on a 33-bus distribution network.

Distributed Generation Planning using Peer Enhanced Multi-objective Teaching–Learning based Optimization in Distribution Networks

In this paper, an optimization technique called peer enhanced teaching learning based optimization (PeTLBO) algorithm is used in multi-objective problem domain. The PeTLBO algorithm is parameter less so it reduced the computational burden. The proposed peer enhanced multi-objective based TLBO (PeMOTLBO) algorithm has been utilized to find a set of non-dominated optimal solutions [distributed generation (DG) location and sizing in distribution network]. The objectives considered are: real power loss and the voltage deviation subjected to voltage limits and maximum penetration level of DG in distribution network. Since the DG considered is capable of injecting real and reactive power to the distribution network the power factor is considered as 0.85 lead. The proposed peer enhanced multi-objective optimization technique provides different trade-off solutions in order to find the best compromise solution a fuzzy set theory approach has been used. The effectiveness of this proposed PeMOTLBO is tested on IEEE 33-bus and Indian 85-bus distribution system. The performance is validated with Pareto fronts and two performance metrics (C-metric and S-metric) by comparing with robust multi-objective technique called non-dominated sorting genetic algorithm-II and also with the basic TLBO.

Maximum penetration level of distributed generation in consideration of voltage fluctuations based on multi‐resolution model

To maintain the safe and stable operation of power system with the interconnection of distributed generation (DG), the urgent need arises to determine the maximum penetration level of DG. Voltage fluctuation, which is especially affected by the stochastic nature of renewable generation and load, has a significant impact on DG penetration. Thus in this study a two-dimensional multi-resolution model, which can demonstrate the impact of renewable generation and load on voltage fluctuation, is proposed. Then an analytical methodology based on the proposed model is presented to determine the maximum penetration level, without violating the limits of voltage fluctuation. Finally, all of them are applied to the IEEE 34 node test feeder, and simulation results show that the maximum penetration level will be lower if the stochastic variations of DG and load are more severe. Therefore the proposed method is a useful solution to the determination of DG penetration, and the multi-resolution model can greatly simplify the process of calculating and analysing.

Impact of Distributed Generation Capacity on the Voltage of Distribution System

Abstract. Large-scale grid-connected distributed generation (DG) will cause out-of-limit of voltage deviation. The model of voltage drop caused by loads and voltage rise caused by distributed generators are established under different loads or DG distribution modes along the line, and the maximum allowable capacity of power injected into the grid without causing over-voltage is calculated, assuming the bus voltage deviation reaching the upper limit. The maximum DG penetration level of typical distribution lines is derived under the condition that generators is of the same distribution mode with loads, and the voltage margin at the head end of the line without causing over-voltage is proposed. The results show that over-headlines can carry much more DG power than cables, and over-voltage will be avoided by controlling the DG capacity according to the connected bus voltage, and suitably lowering the bus voltage will allow much more DG to connect into the grid.

Assessment of maximum distributed generation penetration levels in low voltage networks using a probabilistic approach

Abstract The main objective of network planning is to determine the technically and economically optimal solution that will ensure continuity of supply and adequate power quality as well as allow further integration of distributed generation (DG), despite its substantial impact on the network performance. The maximum DG penetration level also has to be planned or at least assessed, and is heavily dependent on the DG location and size and on the voltage control method. The paper presents a probabilistic approach to network planning, which has many advantages compared to the traditional approaches using estimated peak values and empirically defined simultaneity factors. The method enables the evaluation of the future voltage conditions and therefore the comparison of different network development scenarios, taking into account the stochastic natures of future DG location and loads consumption. By analyzing different solutions, it is possible to minimize the necessary investments in the network. The planning method is presented on an actual low-voltage (LV) distribution network, but it can be used also in medium-voltage (MV) network planning as well.

A Protection Coordination Index for Evaluating Distributed Generation Impacts on Protection for Meshed Distribution Systems

Depending on the capacity, type and location, distributed generation (DG) can have an impact on protection coordination of directional over-current relays for looped distribution systems. In this paper, a new index is proposed, “protection coordination index” (PCI), which can serve as an effective measure when planning the protection of meshed distribution systems with DG. A two-phase non-linear programming (NLP) optimization problem is proposed to determine the PCI by optimally calculating variations in the maximum DG penetration level with changes in the protection coordination time interval. Furthermore, the influence of connecting a DG at a certain location on the system PCIs is examined. The presented analysis is tested on the distribution section of the IEEE 14-bus and IEEE 30-bus systems. The PCI can serve as an efficient index for distribution system planners: (i) to determine the best DG candidate locations for utility owned DG and (ii) to evaluate the impact of a customer owned DG, considering distribution system protection.

Optimal penetration levels for inverter-based distributed generation considering harmonic limits

The installation of inverter-based distributed generation (DG) has been increasing rapidly in recent years, and specifically, photovoltaic power systems. Such increased penetration will result in increased harmonics which could exceed the IEEE 519 allowable harmonic distortion levels. In this paper, the maximum DG penetration level is determined taking into consideration the IEEE 519 allowable voltage harmonic limits. The proposed study is formulated as a mixed integer non-linear programming (MINLP) problem where harmonics are determined using the decoupled harmonic power flow approach. The maximum DG penetration level based on optimal DG size and location is determined using particle swarm optimization (PSO) algorithm. The proposed formulation is tested on 18-bus and 33-bus radial distribution systems considering ten load and DG scenarios. The results show that by decentralizing the DG capacity, higher penetration levels could be achieved. The limiting effect of preinstalled DG at a certain bus on the overall DG penetration is also analyzed.

Maximum penetration level of distributed generation with safety criteria

AbstractMany recent blackouts might raise a concern on how the introduction of distributed generation (DG) (from renewable or non‐renewable energy resources) into the network influences its secure operation in terms of dynamic performance. The anti‐islanding criteria of DG may harm the secure operation of the power system. In this paper, the maximum penetration level of DG is determined using dynamic studies. Tested systems are applied to verify a proposed methodology. The results show that the protection settings have an influence the maximum penetration of DG and the system secure operation. Copyright © 2009 John Wiley & Sons, Ltd.