An on-line pre-decision based transient stability control system for the Ertan power system

The Ertan Hydroelectric Power Development Project with a total capacity of 3300 MW and the associated 500 kV power transmission project is the largest of its kind in China before the Three Gorges Power Transmission Project. An on-line pre-decision system (OPS-1) has been built and tested in the laboratory for its emergency control. Based on on-line stability analysis and pre-decision-making, OPS-1 follows the measured operating condition and refreshes the look-up decision table periodically. Therefore, it is adaptive to operating condition change and structure evolution of the power system, and is a fundamental innovation on the present emergency control system. OPS-1 integrates the unique EEAC technique for quantitative analysis of stability, an integer programming for nonconvex nonlinear optimization of transient stability control, an object-oriented distributed processing platform for contingency-oriented parallel computation into distributed devices for emergency control. The control system structure, decision searching algorithm and laboratory test results are presented in this paper.