This paper presents a secondary voltage control system considering rapid dynamic var compensators，such as static var compensator/static synchronous compensator（SVC/STATCOM）.In order to take full advantage of the rapid adjustment feature of SVC/STATCOM in static voltage control and transient voltage stability，two independent control stages are dealt with.In the first stage，SVC/STATCOM and conventional var compensators are incorporated in the coordinate secondary voltage control model to bring the rapid adjustment feature of SVC/STATCOM into full play.In the second stage，a quadratic programming model is designed to do the optimal control of the dynamic reactive power reserves.The reactive power compensation of the slow dynamic var compensators is substituted for that of SVC/STATCOM，and the dynamic reactive power reserves level is improved.Through coordination between sequence and space，all kinds of reactive power compensators are made full use of in the secondary voltage control and transient voltage stability prevention control.Nordic system test results show that the system can greatly improve the response speed of traditional secondary voltage control while avoiding the conflict between SVC/STATCOM and the traditional reactive power compensators.At the same time，the system is able to carry out effective preventive control of transient voltage stability and improve the recovery effect of system voltage after the disturbance.