A Surge-Impedance Analog of a Large Generating Plant Switchyard

Surge-impedance analog studies of lines and stations as illustrated in this paper are applicable to a wide range of powersystem surge performance problems. It is conceivable that a building-block type of analog could be constructed with plugin units designed to represent circuit elements such as a single station bay, a line entrance, or an entire bus section. Regardless of how the analog may be constructed, the method offers a low-cost reasonably simple method to obtain surge performance data on complex circuits that otherwise could only be approximated. As these approximations have, in many past cases, contained what might be termed ignorance factors, the result has been extreme conservatism in the application of overvoltage protective devices. This is evident in the widespread