This paper presents a coordinated control of STATCOM for an existing voltage control device to improve voltage stability. The voltage control in a power system is usually in charge of a load tap changer (LTC) of a transformer. However a STATCOM is installed in the power system, and it controls the voltage of the power system instead of the LTC because of quick response of the STATCOM. When the STATCOM supplies reactive power to the power system before a contingency, it could not improve the voltage stability. A method that the slope reactance of the STATCOM is changed by voltage deviation is proposed in the paper. It is verified that the proposed method is effective for improvement of the voltage stability by a voltage stability analysis and simulator tests.
展开▼
