Parameters Optimization of VSC-HVDC Control System Based on Simplex Algorithm

The performance of VSC-HVDC system depends on the parameters of control system, and usually PI controllers have been used to adjust system to fulfill desired objectives. However, the optimization methods for PI controllers´ parameters of VSC-HVDC system are very few up to now. A control strategy based on direct analytic expression for VSC- HVDC is presented and the corresponding control system is designed. Simplex algorithm and system objective function are adopted to optimize the PI parameters for single- and multi- objective VSC-HVDC system on the basis of the control strategy. Simulation results in PSCAD/EMTDC software testify the performance of VSC-HVDC control system with optimized PI parameters and show that the controllers with the optimized PI parameters can effectively control VSC-HVDC system. Advantages of the control system with optimized parameters, such as precise control, quickly responding time and strong robustness have been testified by step response.