Selection of Dynamic performance control parameters for classic HVDC in PSS/E

Abstract

The objective of this thesis work is to define the strategy of tuning current controller amplifier and voltage dependent current order limiter parameters to achieve good dynamic performance with a wide range of a.c. systems in PSS/E. The defined control parameter could be adapting independent of different power levels and configurations. Basically, three different HVDC transmission types are used such as overhead lines, cables and back to back. The dynamic control performances are varied with respect to transmission types. Hence, the control parameters could be different. The control parameters could be intended for stability improvement of HVDC system connected with wide range of AC system parameters. As a part of a HVDC project design, large efforts are made in tuning control system parameters for the specific project conditions. However, for customer support, in planning studies it is necessary to provide a set of robust control parameters giving a representative performance for “any” configuration. This thesis work mainly deals with dynamic response of HVDC system. The dynamic instabilities occur mostly at d.c. system connected to weak receiving a.c. network. It causes high ac voltage fluctuations as a consequence very difficult to recover the dc system after the fault clearing instant due to repetitive commutation failures. Therefore, good dynamic dc control strategy has to define by tuning the current control amplifier and voltage dependent current order limiter. This will be done by analyzing the responses of the HVDC model for different transmission types, network strengths and control parameters. Results will be evaluated, and presented so that it is possible to define performance and what needs to be improved. Evaluation will be made of the responses obtained using the existing parameters and those obtained using the set of rules proposed in the thesis.