Reserve indicator with security and stability constraints taken into account for power system security assessment

Security assessment is an important means to prevent large-scale blackouts. This paper proposes an overall evaluation indicator from a macro perspective of the grid security. The indicator is proposed from the view of the main task of the grid operation. It takes the reserve level as the carrier and sets various security and stability constraints on power outputs to get the total maximum output of generators, which gives the true ability of power output. Firstly the various operating constraints should be converted to be the output constraints of generators based on the existing studies of security assessment. Then the true ability of overall output of all generators would be obtained by an optimization model considering the above various constraints. A simplified model is got through reasonable simplification and is used for illustration. IEEE14 testing system and a practical system of one province in China are used to illustrate and verify the simplified model.