Second-order cone programming relaxation-based multi-period reactive power optimization with VSC-Type HVDC and DFIG

Abstract

This paper presents a second order cone programming (SOCP) formulation of the dynamic reactive power optimization (DROPF) problem for the voltage source converter (VSC)-based high-voltage direct current (HVDC) transmission network, considering reactive power support of the doubly fed induction generator (DFIG). In this model, the reactive power support of DFIG, VAR compensators, the position of tap-changer and the states of VSC converters are formulated as continuous and discrete decision variables. By using approximation techniques, the original non-convex optimisation model is converted into a mixed-integer second-order cone programming model. Later, the SOCP formulation can be solved using many standard optimization packages. Then a DC system with VSC technology is modelled in the IEEE 30-bus example system. The SOCP formulation of AC-DC DROPF is applied to the modified IEEE 30-bus example system and the results are discussed.