Dynamic assessment of voltage & reactive power control in Oman Transmission System

The paper presents dynamic assessment of voltage and reactive power control in the Main Interconnected Transmission System (MITS) in Oman. Two case studies are considered; namely the MITS with and without temporary diesel generators. Voltage and reactive power control is achieved by optimization process to maximize reactive power margin of generating units to maintain as much as possible reserves on different generators. The optimal power flow technique is used to determine the optimal settings of the control facilities. These include adjustment of generation reactive power injections, transformer tap-changers and switching on/off of controllable shunt capacitors. The objective is to verify that the MITS is able to achieve an adequate steady-state voltage profile and acceptable dynamic performance. Simulation results are presented to show the dynamic performance of the system when it is subjected to a large disturbance such as outage of a generating unit or outage of a transmission circuit.