A New Method for Electromagnetic Transient Simulation of DC Capacitor in Full-Power Converter

Electromechanical transient simulation is an essential tool for the stability analysis of large power grids. Commonly used electromechanical transient simulation models of power electronic devices such as new energy are relatively simple, neglecting the dynamic characteristics that can reflect the key state variables inside the equipment. The DC capacitor is an important part of the converter, and its dynamic characteristics are closely coupled with the converter control. The electromechanical transient simulation method for the DC capacitor in power electronic devices is one of the keys affecting the accuracy of simulation results. A new electromechanical transient simulation method for the DC capacitor of a full-power converter is studied. The detailed automatic parameter adjustment method for the direct-drive wind turbines and photovoltaic power generation systems is proposed. In this method, the simulation accuracy of the DC capacitor is improved, and the simulation step is not reduced. The method has been applied to the PSD software. Finally, the effectiveness and feasibility of this method is verified in practical projects.