SESShield is a complement to the considerably more powerful SESShield-3D package, providing optimized lightning shielding system heights for substations, shielding performance estimates for substations and transmission lines and detailed risk assessments in accordance with IEC 62305-2.

The substation and transmission line shielding analyses are based on the most recent electro-geometric Rolling Sphere theories and methods described in the IEEE 998, IEEE 1243 and IEC 62305 standards.

The main purpose of the design component of this software package is to assist the user in optimizing the location and configuration of shield wires and masts in order to prevent the exposure of energized conductors, busses and equipment to direct lightning strikes of excessive magnitude. The risk assessment module, for its part, provides a formal assessment of the risk of different types of loss pertaining to vulnerable structures.

Main Interface – Optimal Position of the Protection System

Technical Highlights

The design component of SESShield is particularly suited to shielding substations made up of parallel bays. The following figure, for example, shows a substation bay, along which shield wires (dotted red lines) and masts (points a1,…,an and c1,…,cn) are installed. SESShield can handle such systems, whether shield wires or masts are to be used for protection. For more complex configurations, use SESShield-3D.

Example of Substation for Which Shielding Can Be Designed with SESShield

SESShield also explores two lightning protection failure mechanisms associated with transmission lines:

  • Back Flashover: SESShield calculates the probability that a flashover will occur across the line insulators because of a lightning strike to transmission line structures or to shield wires to which they are connected.
  • Shielding Failures: SESShield also calculates the probability that a large magnitude lightning strike will miss the shield wires or transmission line structures and terminate directly on the phase conductors. SESShield computes the optimal position of each transmission line shield wire for effective shielding of each phase conductor. SESShield computes the corresponding shielding angles between shield wires and phase conductors.

The risk assessment module integrated into SESShield allows you to assess the risks related to lightning strikes on a structure, based on a formal procedure set forth in IEC 62305. The risks include damage to the structure itself, its components and contents, and may also extend to the surroundings of the structure and even involve the local environment. This type of analysis can help in selecting appropriate protection measures that reduce risks associated with lightning to a tolerable level.

Main Interface – Fluctuation of Critical Stroke Current

Input data for the characteristics of the structure

Complex Systems

Whereas SESShield rapidly designs shielding systems for simple substation and transmission line geometries and carry out formal risk assessments, SESShield-3D is the ideal software tool to model arbitrary complex 3D systems and design their lightning shielding systems using all industry-accepted methods.