An indirect model of SSSC for reducing complexity of coding in Newton power flow algorithm

In this paper, an indirect modeling approach for static synchronous series compensator (SSSC) is proposed for Newton power flow analysis. This model shows that addition of ‘p’ SSSCs to an existing ‘n’ bus power system can be represented as an equivalent ‘(n + p)’ bus power system, without any SSSC. As a result, standard power flow analysis of the ‘(n + p)’ bus system can be carried out to calculate the steady state operating point of the original system containing SSSCs. Absence of any SSSC in the transformed system eliminates the need of writing new codes for computing the power flow equations and the Jacobian elements pertaining to SSSCs. This results in a substantial reduction in the programming complexity. The proposed model can also easily account for converter switching losses and various practical device constraints. Application of the proposed model for multiple SSSCs in the IEEE 30-bus, IEEE 118-bus and IEEE 300-bus systems demonstrates the feasibility of the model and its excellent convergence characteristics.