A new method of enhancing reliability for transmission expansion planning

The reliability plays a significant role in power systems and it is an important objective or constraint in transmission expansion planning. Firstly, a DC optimization model was proposed to calculate the maximum arrival power at each load point. Compared to the network flow method, DC model is closer to the actual power flow and it is able to obtain more realistic reliability assessment results. Furthermore, a novel sensitivity index (SI) was also proposed to choose the most effective line so as to enhance the nodal and/or system reliability. The Monte Carlo simulation is used to simulate the system components state. This improved reliability evaluation method and SI can be used for transmission expansion planning or maintenance scheduling. Tests are performed using 6-bus system derived from the Garver's system and the IEEE 10-machine 39-bus system. The results show the effectiveness of the method.