Virtual Synchronous Generator Strategy for VSC-MTDC and the Probabilistic Small Signal Stability Analysis

In this paper, a new virtual synchronous generator (VSG) strategy based on the V-2-P droop control strategy is proposed for the voltage source converter based multi-terminal high voltage direct current (VSC-MTDC) system. The VSG strategy enables the inverter stations to damp the power oscillation and provide frequency support for the AC system. Virtual inertia coefficient is obtained to couple the DC voltage and the angular frequency. To provide the oscillation damping and frequency support, the inverter stations could adjust the output power by the adjustment of the DC reference voltage. Due to the characteristic of the V-2-P droop method, there is no requirement for the communication between inverter stations. The Monte Carlo method is used to test the probabilistic small signal stability of the VSG strategy. The performance of the proposed controller is demonstrated by a hybrid AC/DC system which is modeled in DIgSILENT/PowerFactory. (C) 2017, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.