R. B. Finn

Bio: R. B. Finn is an academic researcher. The author has contributed to research in topics: Lightning arrester & Transmission line. The author has an hindex of 1, co-authored 1 publications receiving 72 citations.

Multistory transmission tower model for lightning surge analysis

Abstract: A multistory transmission tower model to be used in multiconductor analysis by EMTP (Electromagnetic Transients Program) is proposed. The circuit parameters of the model are determined based on the measurement of voltages across the insulator strings on an actual 500 kV transmission tower. The multiconductor lightning surge analysis considered enables one to predict the waveform of each insulator voltage, which is useful in determining the phase and the instant of a back flashover. The new tower model is recommended in Japan to be used in the new multiconductor analysis of EHV and UHV class double circuit transmission lines. The new tower model and conventional tower models are compared in the analysis of minimum back flashover lightning currents at a UHV transmission line. The new model gives about 20% smaller current. >

Experimental evaluation of a UHV tower model for lightning surge analysis

Abstract: An experimental investigation was performed on a UHV tower model for the EMTP multiconductor calculation of lightning overvoltage at substations associated with back-flashover at an adjacent transmission tower. The various lightning surge response characteristics were measured on an actual UHV tower, and parameters of a multistory transmission tower model that can reproduce voltages across the insulator strings, voltages of the crossarms, and voltages of the power lines were determined. A value of 120 /spl Omega/ was determined as the surge impedance at each section of the multistory tower model, which closely agreed with the tower surge impedance measured for the UHV tower alone. >

Lightning Induced Voltages on Power Lines: Theory

Abstract: Theory is presented which shows that nearby lightning return strokes can induce voltage surges of either positive or negative polarity on an overhead line depending on the location of the lightning relative to the line. The Telegraphers' Equations are solved with the return stroke vertical and horizontal electric fields as forcing functions. The hori zontal electric fields are calculated from measured or assumed vertical fields and assuned earth conductivities. For a typical return stroke, voltage waveforms are presented for a line of 500 m length and one of 5 km length for the following conditions: earth conductivities between 10-2 mhos/m and 10-5 mhos/m, earth permittivities between ??= 15 and ??= 3, and lightning ground strike points between 0.2 km and 5.0 km of the line at a variety of positions around the line. Measured voltages on a 460 m test line described in a companion paper are compared with calculated voltage waveforms derived from measured vertical electric fields, in accordance with the developed theory. Calculated waveshapes are found to be in moderately good agreement with the measurements, but calculated magnitudes are about a factor of 4 lower than measured. Possible errors in both theory and measurement are discussed. Voltage measurements reported by other investigators are, in general, consistent with the present theory

IEEE working group report. Estimating lightning performance of transmission lines. II: Updates to analytical models

Abstract: The IEEE Simplified Method [33] for computing lightning performance of overhead transmission lines was first described by Anderson [5]. Since its publication, considerable experience has been obtained in the application of the method and in the testing of various component models. This paper describes application experience, sets out the theoretical basis for modifications and provides a framework for future advancements

A New Approach to the Calculation or the Lightning Perrormance or Transmission Lines III-A Simplified Method: Stroke to Tower

Abstract: 1. Simplified methods of calculating the voltage across the insulator string are presented based on field-theory concepts for a stroke to the tower with zero towerfooting resistance. 2. The voltage across the insulator string is composed of two components: (a). that produced by the rent and the charge fed into the tower and ground wires, and (b). that produced by the charge above the tower. 3. To calculate the voltage produced by the current and charge fed into the tower and ground wires, conventional traveling-wave theory and methods can be used provided the proper value of surge impedances are used. 4. Equations, based on field theory, are presented to calculate the ground wire and tower surge impedances and the conductor-to-ground mutual impedances. 5. The development of travelingwave theory directly from field theory places traveling-wave theory on a more rigorous basis. 6. To calculate the voltage produced by the charge above the tower, approximate simplified equations are given for a given stroke mechanism. These can be modified for other assumptions. 7. From examples and calculations given in this paper it is possible to gain some insight on the effect of tower geometry, number of ground wires, and position of the conductor on the voltage across the insulator string. Voltages were calculateed across the top and bottom insulator strings of the single-groundwire AEP-OVEC 345-kv tower, across the top insulator string of the two-groundwire AEP-OVEC 345-kv tower, and across the insulator string on the PW&P 220-kv tower.