Developed HVDC power injection model for power flow analysis with multi-control functions considering operating constraints

This letter proposes a simple modeling for multi-control modes of HVDC into Newton–Raphson load flow algorithm. This modeling is based on power injection approach. HVDC is represented with injected loads as a function of the desired power flow through transmission line. During the iterative process, these loads are updated and injected at the terminal buses of HVDC. Four control modes of HVDC are presented to control the sending bus voltage and the active and reactive powers flow individually or simultaneously in a transmission line which only includes the HVDC. The main advantages of the proposed model are reducing the complexities of incorporating HVDC in load flow code and avoiding the Jacobian matrix modifications. In addition, this paper proposes a simple operating constraints handling strategy of HVDC. The proposed model is validated using IEEE 30-bus, IEEE 57-bus and IEEE 118-bus test systems to prove its feasibility and efficiency.