A novel method for VSC-HVDC electromechanical transient modeling and simulation

VSC-HVDC (Voltage Source Converter High Voltage Direct Current) transmission system is a recent HVDC technology. The paper presents a new way of VSC-HVDC electromechanical transient modeling and simulation, which is based on the theory of equivalent sources. This method uses equivalent sources to substitute for voltage source converter, in addition, there are no simulation of IGBTs or PWM trigger modular, so it is more appropriate for electromechanical transient modeling and simulation. By this way, the detailed dynamic model for VSC-HVCD is developed. This model includes four parts, i.e. the normal ac system, the VSC-HVDC inner dc system, the interface between ac and dc system and the VSC-HVDC control system. Then a case of VSC-HVDC transmission system is established in PSCAD, the results show that by using this method for VSC-HVDC electromechanical transient modeling and simulation, not only the steady-state power flow can be controlled, but the system can achieve ideal dynamic response.