Eric J. Stacey

AEP unified power flow controller performance

The installation of the worlds first unified power flow controller (UPFC) has been completed and a series of commissioning tests were conducted at the Inez Substation of American Electric Power (AEP) in eastern Kentucky. The project is a collaborative effort between AEP, the Westinghouse Electric Corporation, and the Electric Power Research Institute (EPRI). Comprising two /spl plusmn/160 MVA voltage-sourced GTO-thyristor-based inverters, this installation is the first large-scale practical demonstration of the UPFC concept, and its completion is a significant milestone in the progress of power electronics technology for flexible AC transmission system (FACTS). This paper briefly reviews the main features of the Inez installation and discusses the operation of the equipment. A collection of measured performance characteristics is presented to illustrate the unique capabilities of the UPFC. These dynamic measurements were made in the course of commissioning, and they graphically illustrate the ability of the UPFC to independently control the real and reactive power on a transmission line, while also regulating the local bus voltage. The results include a demonstration of the series inverter at Inez, operating in stand-alone mode. This test constitutes the first practical large-scale demonstration of the static synchronous series compensator (SSSC) concept.

AEP UPFC project: installation, commissioning and operation of the /spl plusmn/160 MVA STATCOM (phase I)

American Electric Power (AEP) has selected its Inez Substation in eastern Kentucky for the location of the worlds first Unified Power Flow Controller (UPFC) installation. Comprising two /spl plusmn/160 MVA voltage-sourced GTO-thyristor-based inverters, this installation is not only the first practical demonstration of the UPFC concept, but also by far the highest power GTO-based Flexible AC Transmission Systems (FACTS) equipment ever installed. The installation will be the first demonstration of this type of equipment connected in series with a transmission line. The project is a collaborative effort between AEP, the Westinghouse Electric Corporation, and the Electric Power Research Institute (EPRI), and has been divided into two phases corresponding to the installation of the shunt- and series-connected inverters respectively. Phase I (installation and commissioning of the shunt inverter (STATCOM)) was completed successfully in July, 1997, and the STATCOM is now operational. Phase II is scheduled for completion in early 1998. This paper gives a brief background to the project, describes the installation and special features of the equipment, and reports on the Phase I commissioning and STATCOM operation.

Operation of /spl plusmn/100 MVAr TVA STATCON

In 1995 a /spl plusmn/100 MVA static synchronous compensator (STATCON) was commissioned for the Tennessee Valley Authority (TVA) at the Sullivan substation in North-Eastern Tennessee, USA. This was an historic milestone in the initiative for flexible AC transmission systems (FACTS) promoted by the Electric Power Research Institute (EPRI). The TVA STATCON is the first of its kind, using GTO thyristor valves, to be commissioned in the United States, and is currently the largest installation of this type in the world. Commissioning tests have now been completed and the STATCON is operating continuously online. The demonstrated performance of the equipment has either met or exceeded expectations in all areas and has proven beyond doubt the viability of this type of equipment in high power transmission systems. This paper briefly reviews the STATCON installation and reports on the static and dynamic performance observed during commissioning.

An "unrestricted frequency changer" employing force commutated thyristors

A new approach for applying forced commutation to a thyristor cycloconverter is presented. Using a known waveform synthesis technique, this type of cycloconverter possesses several unique characteristics. The theory of operation as related to a six-pulse, three-phase bridge configured cyclonconverter is presented. Performance of a working model is illustrated in the form of calibrated waveform oscillographs. In view of its simplicity, high efficiency and technical advantages, this type of cyclonconverter is worthy of consideration for many power frequency applications.