No abstract

No abstract

No abstract

We have newly developed an 80MVA GCT STATCOM for the Kanzaki substation of the Kansai Electric Power Co., Inc. It has been started commercial operation in June, 2004. The main purpose of the STATCOM is to maintain voltage during single circuit connection of source to the substation resulting from an AC system fault in order not to break down load system of the substation. The developed STATCOM has three distinctive features: (1) a high-efficient, compact and AC filter-less system using multistage three-level GCT converter and customized PWM; (2) a coordinated voltage regulator with tap control of main transformers; and (3) a continuous operation from a single phase-ground fault through reclosing of the faulted circuit by limiter adjustments of the reactive current reference. This paper describes characteristics of the coordinated voltage and validity the continuous operation during AC system faults using data of commercial operations and the simulation results.

PacifiCorp commissioned the St. George Static Var System (SVS) with a continuous rating of -35 to +100 Mvar (transient rating -70 to +278 Mvar) in June of 2006. This paper presents the Southwest Utah area transmission system, the requirements for voltage support, the planning and dynamic performance studies used in rating and verifying performance of the SVS, and provides an overview of the design and coordinated control strategy. An overview of the SVS stability model with integrated "smooth' and "stepped" susceptance control is also discussed. The St. George SVS is connected to the 138 kV bus of the St. George substation to enhance voltage control and dynamic Var support for major disturbances in the Southwest Utah 138 kV and 345 kV transmission systems. The SVS coordinated control strategy employs local and remote shunt reactive devices to reduce SVS reactive steady-state output and to regulate the voltage at the local St. George 138 kV bus and at the remote Red Butte 138/345 kV substation.