Modeling and Dynamic Characteristics Analysis of DVR Inverter

Dynamic voltage restorer (DVR) can rapidly output a compensation voltage with required amplitude and phase angle when voltage disturbance occurs in the grid. So it is equivalent to a controlled AC controlled power source and its core part is an inverter. Modeling and dynamic characteristics is the basis and premise of DVR design. The paper constitutes the mathematic model and deduces the equivalent circuit of H bridge inverter of DVR used in low-voltage distribution grid. By virtue of the model, this paper analyses the key factors related to dynamics characteristics of DVR inverter. Based on theoretical analysis, transient process is simulated under various situations. Simulation results indicate three-H bridge DVR inverter has high response speed and can meet the demand of voltage compensation.