Techno-Economic Assessment of Voltage Sags Mitigation in Distribution System Connected to DGs

The penetration of DG in electrical distribution systems has many benefits. The paper highlights the impact of DG penetration at different load centers and different operating conditions in a distribution feeder. The impact of DG penetration on feeder voltage profile that depends on the size and location of DG in the system is illustrated. Mitigating methods are used to reduce the effect of voltage disturbances. Economic assessment studies are used for assisting in the economic choice of mitigating methods. Economical aspects of distribution systems connected to DGs are considered through the analysis of the life cycle cost of these distribution generation sources. Maintenance strategies are illustrated and discussed to keep these sources always ready for operation regarding minimization of maintenance cost. Technical and economical assessments depend on the availability of historical data for disturbances cost including damages and cost of disturbance mitigation using different mitigation methods. These data are difficult to be available for different types of loads. Therefore, load indices, K1, K2, and K3, are proposed in this paper for the different loads as referring it to reference load has available data to overcome the challenge of data shortage. Also, a techno-economic assessment index F is proposed for the assessment of the impact of mitigating device improving cost and its feasibility. PSCAD/EMTDC simulation software package is used in this analysis. The results show that the proposed techno-economic assessment methodology facilitates the decision of choosing the mitigation method for power quality problems and to overcome the challenge of data shortage in the techno-economic assessment.