تحسين أداء شبكة الضغط الفائق العراقية بالأعتماد على HVDC مع المصفوفة الطاقة الكهروظوئية

Performance Improvement of Iraqi High Voltage Grid Based on HVDC With PV Array

Abstract

The Iraqi extra-high voltage 400kV network has been experiencing a voltage drop and power loss over the past few years. The objective of this thesis was to connect a new power plants, utilizing one of the renewable energy sources which is a solar cells, to the existing network via HVDC. The Power System Simulator for Engineering (PSS/E) software has been employed to simulate and analyze the power flow within the system, examining the impact of HVDC transmission on voltage profile, short circuit level, and transmission losses within the network. The Iraqi extra-high voltage 400kV network under consideration comprises 57 buses distributed across four regions: northern, central, middle Euphrates, and southern, as per the Iraqi Ministry of Electricity (MoE). A solar power plant with a capacity of 150MW was proposed, consisting of 1740 panels, each with a capacity of 300 W using SunPower SPR-305-WHT cells, which is integrated into the network. To mitigate a voltage drop in Samawah Governorate, an auxilary bus bar was added, which was measured 388.5kV in the winter and further decreased in the summer. The resulting power was transmitted using a bipolar voltage source converter, which reduced the total system losses. Subsequently, this power was transferred to BUS No. 24401 Samwa [SMWCC-400kV], leading to a decrease in total losses from 379.02MW to 356.31MW. Reactive losses were efficiently reduced from 3198.36 to 2855.75 MVar. During peak periods, BUS No. 24401 [SMWCC-400] experienced a voltage drop of approximately 388.5 KV, which was addressed through improvements, resulting in the voltage that reaches 400kV. Additionally, the short-circuit current in the specific southern region around the Samawah and Al-Muthanna bars showed a significant improvement compared to the period that presence a voltage drop.