Optimization Of Control Parameter Of Multi-Infeed HVDC System

The stability of HVDC system is improved by optimization of system’s control parameters value in this thesis research. The network simulation model is designed in PSCAD, and the PI (Proportional Integral) control parameters optimization is achieved by using simplex algorithm. Simulation based OF (Objective function) is introduced in this paper; Simulation calculations are practiced to determine the fitness values of OF. The model of multi-infeed HVDC systems of Central-East China power system is used as a test network. PI control parameters of Three Gorges-Changzhou ±500KV HVDC system line are optimized. Furthermore, the optimized control parameters are implemented on other remaining HVDC lines. The results produced after multi-runs of optimization process are presented by graphs. The performance of system is improved after optimization, as compared to initial values. And the system shows steady behavior with optimized controller parameters.The simplex optimization technique is used to optimize HVDC control system by amending PI parameters; which in turn help to improve the stability of a system. Simulation based Objective Function is used to find optimum results i.e. OF is designed on the basis simulation result of current error in each run of multi-run simulation. Voltage stabilizing time and current overshoots are improved after putting new values in a control system of multi-infeed HVDC systems.PSCAD simulator is being used to achieve this goal; as this simulator is specially designed for Power simulation, so it works very fast and gives accurate results. Interconnection of Central and Eastern Power system of three lines HVDC system is very complex and large, so PSCAD simulator is used because of its qualities of fast simulation and capable to handling large simulation system. Moreover, PSCAD also have simplex optimum block for optimization. Simplex optimum is used to find convergent solution of objective function.From the experiments conducting in this simulation, it can be safely concluded that overall performance of the system is improved by optimizing control parameters. Moreover, the results showed good stability of system, when AC side faults were introduced.