Multistage Preventive Scheme for Improving Voltage Stability and Security in an Integrated Renewable Energy System

摘要

The trend of renewable energy integration, power system size and complexity growth, occurrence of line contingencies, andrnmore stressed loading conditions for power systems increase the threat of voltage stability, which has recently been among thernmain problems in power systems. This paper proposes a multistage preventive scheme based on voltage stability and securityrnmonitoring and control. A security-constrained optimal power flow considering voltage stability and renewable energy generationrnuncertainty, inductive and capacitive reactor tap change minimization, and load shedding minimization problems is implementedrnin the proposed method. The proposed method ensures voltage stability under the uncertainty of renewable energy generation andrnselected line contingencies considering their occurrence probability and/or voltage instability severity level. Several cases basedrnon a modified IEEE 57-bus test system are used to demonstrate the effectiveness of the proposed method. The simulation resultsrnshow that the proposed method can make an important contribution to improve voltage stability and security performance underrnsevere conditions.