GIS based modelling and analysis of unbalanced LV distribution networks with distributed energy resources

Download
2019
Özdamar, İsmail
Conventional low voltage (LV) distribution networks are radially designed and operated in pre-defined loading limits and voltage range. However, with the increasing electricity demand and distributed generations (DGs) resulting reverse flows and under voltages, LV networks will have serious problems such as overloading and voltages out of limits. With the integration of distributed energy resources (DERs) in the system such as distributed generations, rooftop photovoltaics, battery storages, and electric vehicles into LV networks, the design and operation of low voltage networks become more complex and require a comprehensive approach including network modelling, calculation and assessment of network voltages and loadings for various scenarios. In this study, all data required for network modelling are extracted from geographic information system (GIS) and the network model, represented as bus-injection to branch current matrix (BIBC), is created by using graph theory. In addition, three phase unbalanced power flow analysis of low voltage networks with P-V buses representing distributed energy resources is developed by using modified backward/forward power flow algorithm. The results for 113-bus test case are verified by comparing the results with that of a commercial software. Main contribution of this study includes the considerable amount of decrease in network modelling effort, and the higher performance and reliability for power flow solution of unbalanced LV networks with DERs.

Suggestions

Series active filter design, control, and implementation with a novel load voltage harmonic extraction method
Şentürk, Osman Selçuk; Hava, Ahmet Masum; Department of Electrical and Electronics Engineering (2007)
Series Active Filters (SAF) are designed for harmonic isolation and load voltage regulation of single-phase and three-phase voltage harmonic source type nonlinear loads. The novel Absolute Value Method (AVM) for load voltage harmonic extraction is proposed and applied in the control algorithm of SAF. The SAF compensated systems are represented by simplified linear models such that SAF controller gains can be easily determined. Harmonic isolation and load voltage regulation performances of 2.5 kW single-phas...
Output voltage control of a four-leg inverter based three-phase ups by means of stationary frame resonant filter banks
Demirkutlu, Eyyüp; Hava, Ahmet Masum; Department of Electrical and Electronics Engineering (2006)
A method for high performance output voltage control of a four-leg inverter based three-phase transformerless UPS is proposed. Voltage control loop is employed and the method employs stationary frame resonant filter controllers for the fundamental and harmonic frequency components. A capacitor current feedback loop provides active damping and enhances the output voltage dynamic performance. The controller design and implementation details are given. Linear and nonlinear loads for balanced and unbalanced loa...
Repetitive control of a three-phase uninterruptible power supply with isolation transformer
Çetinkaya, Süleyman; Hava, Ahmet Masum; Department of Electrical and Electronics Engineering (2006)
A repetitive control method for output voltage control of a three phase uninterruptible power supply (UPS) with isolation transformer is investigated. In the method voltage control loop is employed in the stationary dq frame. The controller eliminates the periodic errors on the output voltages due to inverter voltage nonlinearity and load disturbances. The controller design and implementation details are given. The controller is implemented on a 5-kVA UPS prototype which is constructed in laboratory. Linear...
Improvement of the electric field distribution in the medium voltage gas insulated inductive voltage transformers
Var, Melih; Keysan, Ozan; Department of Electrical and Electronics Engineering (2017)
IVoltage transformers are commonly used in medium voltage systems for both protection and measurement purposes. These transformers are designed to satisfy the mandatory IEC requirements at the lowest possible cost. The average life expectancy of such transformer is about 20 years, reliability and robustness are of the utmost importance. The main cause of failure during rated operation is the deterioration of the solid insulation by partial discharges. Partial discharges, unless there is a manufacturing erro...
Sinus Output 3-Phase Inverter Topology for Improved Drive Efficiency
Ertan, Hulusi Bülent (2014-09-24)
Traditionally electrical drives and uninterruptable power supplies generate pulse width modulated outputs. Harmonic content of such waveforms are known to cause problems. Therefore, it is worthwhile to investigate 3-phase sinus output topologies, which can compete with traditional inverter topologies, regarding performance and cost. In this paper, first some topologies for producing single-phase sinus output are reviewed. Then, the possibility of using these single-phase units for producing 3-phase output i...
Citation Formats
İ. Özdamar, “GIS based modelling and analysis of unbalanced LV distribution networks with distributed energy resources,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Electrical and Electronics Engineering., Middle East Technical University, 2019.