Abstract
M.Ing.
Electrical quality of supply affects every consumer, from the homeowner to large industry and mining. Customer awareness of poor power quality is increasing due to the more sensitive nature of modern equipment. The positioning of a new plant is therefore very important and cannot only be determined by the availability of resources in the area.
To determine the quality of the electricity in a certain network, years of historical data is required. To get enough information regarding a distributions network performance would require voltage dip measurements at a few places in the network for at least three years. For this reason a new method are used in this study. By using the existing information in a network, like:
• The amount of lightning strikes per year
• The amount of electrocuted birds
• The type of protection used
• The amount of vandalism incidents on a line per year
• The tower footing resistance
• The fault level in the network
The fuzzy logic principle can be used to determine how susceptible a network is to voltage dips, by determining the favourable and unfavourable conditions for a number of membership functions.
Conventional set theory (Boolean) states that an element is either a member of a set or not. Fuzzy logic is an extension of conventional set theory enabling an element to belong to a set degree.
This study will look at all the important factors influencing voltage dips, and to use these factors in a fuzzy logic program to determine the voltage dip risk factor for new customers setting up plant in a specific network.
The voltage dip risk factor will then determine if it is cost effective for a customer to take on the additional cost in dip proofing his plant.