Reliability Evaluation and Sensitivity Analysis to AC/UHVDC Systems Based on Sequential Monte Carlo Simulation

With the sequential Monte Carlo simulation (sMCs), the duration of the system state is obtained by the difference of the state sequences of related equipments. The state probability is not the explicit function of the reliability parameters. Therefore, it is difficult to derive the sensitivity directly. A new sensitivity model for the sMCs is proposed in this paper which is based on the derivative of the state duration to the reliability parameters, and the sensitivity model is applied to the AC/UHVDC system. The states and durations of the related equipments from the beginning of the simulated years to the generated time of the system state are considered and differentiated to describe the derivative. To obtain the sequence of the UHVDC line, the possible reached state, mean duration, and probability for each state transition are considered. By combining the sensitivity model of the UHVDC line itself, the equivalent transition rates are applied to connect the system state duration and reliability parameters of the UHVDC components. The numerical results based on a provincial system in China are provided to validate the feasibility and accuracy of the proposed model.