Richard Cheung
Power / Controls
The nuclear generating station grounding system includes ground grid, grounding of generator isolated-phase bus, grounding of structures, grounding of station auxiliaries, lightning protection of structures, grounding of buried structures, grounding of instrumentation and control systems, etc. The ground grid is to safely conduct to ground the largest ground fault current and limit the touch and step voltages in the outdoor areas of concern; the isolated-phase bus grounding is to limit the touch voltage on the enclosure in event of a fault in the bus enclosure; the grounding of structures is to prevent dangerous touch voltages from faults or from static induction; the grounding of station auxiliaries is to prevent dangerous touch voltages due to local faults or equipment failures in the station auxiliaries; the grounding for lightning protection of structures is to protect the station from the direct and indirect effects of lightning strikes; the grounding of buried structures is to avoid the transfer of high ground voltages; the grounding of instrumentation and control systems is to keep touch voltages within safe limits and ensure proper operation of equipment. The primary focus of this project is, however, on the station ground grid design.
The objective of this project is to design an effective grounding system in order to protect personnel in the generating station against dangerous touch voltage and step voltage and to protect property from damage. In case of a fault occurring in the generating station and its surroundings, the grounding design is to limit the resulting touch and step voltages to acceptable levels.
Design an effective ground grid for nuclear generating station. Determine the ground grid requirements and simulate the limiting values of the touch voltage and step voltage for a typical configuration of a ground grid for nuclear generating station application.
Provide a low-impedance ground fault current return path in order to activate the protection system that alarms and clears the ground fault as soon as possible. Limit the voltages on station structures and accessible equipment both during normal operation and during electrical transients to safe levels. Minimize electrical noise interference in control and instrumentation systems. Minimize the effect of lightning strikes on personnel, equipment and structures.
Study IEEE Std. 665-1995, “IEEE Guide for Generating Station Grounding” and IEEE Std. 80-2013, “IEEE Guide for Safety in AC Substation Grounding”.
Study literature on nuclear generating station grounding.
Design an effective ground grid for a typical nuclear generating station. Perform design analysis. Perform design simulation and design optimization.
Research the grounding requirements for a typical nuclear generating station. Learn how to determine a ground grid to provide personnel safety. Share experience of determining ground grid requirements. Carry out ground grid design, design simulation, and design analysis.
Research hand calculation methods for ground grid design. Learn how to use hand calculation for ground grid design. Share experience of using calculation method for ground grid design. Carry out ground grid design, design simulation, and design analysis.
Research simulation methods for ground grid design. Learn how to use simulation tool for ground grid design. Share experience of using simulation tool for ground grid design. Carry out ground grid design, design simulation, and design analysis.
ELE 637
RC05: Design of Nuclear Generating Station Grounding | Richard Cheung | Not yet submitted at No time