| Summary: | Thesis (MTech (Electrical Engineering))--Cape Technikon, Cape Town, 2003 === The aim of the thesis is to investigate and develop a technique for predicting the flicker
emission of sawmill loads. The technique makes use of an empirical formula to calculate the
characteristic coefficient of a sawmill motor (Ksm) and depends upon the short term flicker
severity level (Ps,), load size and fault level.Three types of sawmill loads are commonly found in South Afiican plants, namely the
Circular, Multi-rip, and Frame Saws. A sawmill plant was selected as a benchmark and Ksm
factors for these types of saws were calculated by application of the empirical formula. These
Ksm factors are required for predicting the flicker emitted by similar saws at other sawmill
plants.A flicker meter was used to measure the flicker values (PsI) for these saws. Fault levels were
calculated for various sawmill sites investigated. Load sizes were determined and the
empirical formula used to calculate the Ksm factors. These Ksm factors were then compared to
those calculated at the benchmark sawmill in order to determine the accuracy of the empirical
formula.Nine case studies were conducted. The sawmills selected for these investigations were in
different geographical forest areas in South Afiica. Different Ksm factors were found and this
can be attributed to the differences in the density and hardness of the wood in the various
areas. It can also be attributed to the mechanical variables of the saws. However, a
comparative analysis of the Ksm factors comparison reveal that many Ksm factors fall within a
similar range and for planning purposes 88,19 and 111 can be used for the Circular, Multi-rip,
and Frame Saws, respectively.The results obtained demonstrate that the developed flicker emission prediction technique for
sawmills is an effective analytical tool to be used for planning the network to ensure that the
flicker levels will remain within acceptable limits.
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