In most of the AC-DC hybrid power transmission system AC filters is widely applied to stabilize voltage level in addition to filter harmonic. However, the voltage stability of AC bus is greatly influenced by action sequence of switching AC filters in group. The paper presents the concept of reactive characteristics of the convertor and AC filters, using reactive and voltage control mode to switch them. The modeling, control, and principle of operation for the AC-side switching filters are described. The voltage level is controlled via regulating action of switching filters by step. The salient feature of the proposed control modes is that voltage control contributes to keep the voltage level, and reactive control has no fast response on guaranteeing voltage stability, but two methods can apply to different occasions based on the requirements of voltage stability. All analysis and control system designs are verified through building a RTDS model in a typical ±500kV power system.
Modeling and Analysis of Positive Output Luo Converter in Voltage Control Mode
