Contingency selection for power system stability analysis

Transmission expansion planning requires static and dynamic analyses. Planning criteria include the selection of contingencies consisting of faults and their clearing, performance standards, transmission system adjustments, and corrective action plan. Performance standards relating to power system dynamics mainly concern the voltage ride through and transient angle stability i.e. retaining synchronism after the occurrence of the contingencies mentioned. The selection of planning contingencies, for which performance standards must be complied with, is important in terms of capital expenditures in transmission network expansion and secure power system operation. This paper discusses planning contingencies accepted by various transmission network operators worldwide and describes a set of planning contingencies proposed by the authors.

I. Introduction

Evaluation of power system performance in the process of transmission network expansion planning is conducted with the use of multivariate deterministic models creating scenarios for the transmission network expansion for various load increase scenarios and planned expansion of generation sources. These evaluations consist of static and dynamic analyses. A review of literature [1]–[11] shows that the scope of static and dynamic evaluation conducted for the purpose of power system expansion planning and/or operation depends on which time horizon is adopted. The largest number of dynamic (including stability) analyses are conducted as part of short-term (horizon up to 3-5 years) and mid-term planning (time horizon up to 10-15 years). No or sporadic, very limited, power system dynamic analyses are performed as part of long-term planning (horizon of 15-30 years).