Research On The Simulation Of AC/DC Power System Based On RTDS

The size and complexity of AC/DC parallel Grid has been increasing during the pastseveral years, with a lot amount of infiltration of HVDC, FACTS and etc. The research ofinfluence between AC system and DC system is much more of a concern, in order to ensurethe security and stability of AC/DC parallel Grid. Building an AC/DC parallel power systemmodel with RTDS based on EMT contains much superiority such as connecting with controland protection equitment. It can be great support for the research of AC/DC parallel Gridoperation and dynamic characteristics. Meanwhile, it’s great significant for technologyresearch and function test such as strategy of grid security and stability, STATCOM, SVC andetc.In this paper, research work includes:Describe hardware and software of RTDS, and the limitations of AC/DC parallel gridsimulation based on RTDS. Refer to the new techology of RTDS, study the FrequencyDependent Network Equivalent (FDNE) in order to building AC/DC parallel Grid based onRTDS.Consider as the requirements of the grid data format and simulation percision, introducesthe model types, parameters and parameter transformation of the main power systemcomponents both of BPA and RTDS.Introduce the User-Defined model (UDC) of RTDS——CBuilder.. Firstly, discussgeneral method and process of CBuilder,. Secondly, verify the accuracy of control modelbased on CBuilder by defining the FV excitation system and dynamic performance test.Last, verify the accuracy of AC/DC parallel Grid RTDS model by comparing simulationresults of steady-state power flow and transient characteristics in steady-state operation andfailure condition with BPA and RTDS. Further, replay the “11.7” accident with the RTDSmodel and analyze the grid characters of commutation failure in multi-DC system.