a) Gather preliminary line design data and available climatic data.^1
b1) Select the reliability level in terms of return period of design loads. (Note: Some national
regulations and=or codes of practice sometimes impose design requirements, directly or indir-
ectly, that may restrict the choice offered to designers).
b2) Select the security requirements (failure containment).
b3) List safety requirements imposed by mandatory regulations and construction and maintenance
loads.(^1) In some countries, design wind speed, such as the 50-year return period, is given in National Standards.
d1. Calculate climatic
limit loads
d2. Calculate loads
related to security
e. Determine strength
co-ordination
f. Select load and
strength factors
g. Calculate required
characteristic strength of
components
h. Detailed design of line
components
Check compliance with safety
requirements of national and
regional regulations
b1. Select reliability level
c1. Calculate climatic
variables
b2. Select security
requirements
b3. List safety requirements
(compulsory)
d3. Calculate construction &
maintenance loads
a. Preliminary design: route selection, cables, insulation design, towers, foundations, climate data, etc.
FIGURE 9.7 Methodology.