ABSTRACT
A direct stroke is defined as a lightning stroke when it hits a shield wire, a tower, or a phase conductor. An insulator string is stressed by very high voltages caused by a direct stroke. An insulator string can also be stressed by high transient voltages when a lightning stroke hits the nearby ground. An indirect stroke is illustrated in Figure 8.1. Illustration of direct and indirect lightning strokes. https://s3-euw1-ap-pe-df-pch-content-public-u.s3.eu-west-1.amazonaws.com/9781315217222/122b661d-0d00-4221-a6b4-e915b4a4fe10/content/fig8_1.tif"/>
