Reactive power substitution between rapid and slow dynamic var compensators

By substituting the slow dynamic var compensator (such as synchronous generator) for rapid dynamic var compensator (such as SVC/SVG) in the static conditions, the rapid dynamic reactive power reservation can be significantly boosted. Therefore, the reactive power reservation can respond to the dynamic network disturbance more effectively. This paper proposes a quadratic programming based optimization model to implement the idea of substituting the slow dynamic reactive power for the rapid dynamic reactive power on the premise of ensuring the system security and keeping an approximate constant voltage of pilot buses. It can keep SVC/SVG a large upward and downward reactive power reservation and ensure the regional balanced reactive power of generators. Simulation results on the New England 39-bus system show that regional rapid dynamic reactive reservation is enhanced and the dynamic voltage stability is improved after the substitution.