COURSE OVERVIEW:

Current Transformers are the critical sensors of the power system, providing the essential link between high-voltage primary circuits and sensitive protection and metering devices. This course explores the fundamental electromagnetic principles that govern Current Transformer operation, focusing on how these devices accurately replicate high-magnitude currents at safe secondary levels. Participants will analyze the construction and physics of magnetic cores, learning how saturation and flux density influence the performance of the entire protection scheme.

The scope of this training addresses the diverse range of Current Transformer designs, including window, bar, and bushing types used in utility and industrial substations. It covers the technical nuances of accuracy classes for both metering and protection applications, emphasizing the importance of the knee-point voltage in high-impedance differential schemes. The curriculum provides a detailed framework for selecting and sizing Current Transformers to ensure they can withstand the extreme thermal and mechanical stresses of a short-circuit event.

Coverage includes rigorous field testing and commissioning procedures designed to verify the integrity of the Current Transformer and its secondary circuit. Attendees will learn to perform and interpret excitation, ratio, and polarity tests using modern automated test sets. By focusing on the interaction between the Current Transformer and the connected burden, the course ensures that protection engineers can design and maintain sensing systems that are both dependable and secure under all fault conditions.

COURSE OBJECTIVES:

After completion of this course, the participants will be able to:

• Explain the electromagnetic induction principles used in Current Transformers.
• Differentiate between protection and metering accuracy classes.
• Analyze the impact of core saturation on protection relay performance.
• Calculate the secondary burden and its effect on measurement accuracy.
• Determine the knee-point voltage of a Current Transformer from its curve.
• Select and size Current Transformers for specific protection applications.
• Conduct ratio and polarity tests using secondary injection methods.
• Perform insulation resistance and winding resistance measurements.
• Interpret excitation curves to verify Current Transformer health.
• Identify the causes and consequences of open-circuited secondary windings.
• Implement proper grounding and shielding for Current Transformer circuits.
• Troubleshooting errors in the current transformer secondary wiring and polarity.

TARGET AUDIENCE:

This course is intended for Protection Engineers, Substation Technicians, Commissioning Specialists, and Electrical Maintenance Personnel responsible for power system measurement.

TRAINING COURSE METHODOLOGY:

A highly interactive combination of lectures, discussion sessions, and case studies will be employed to maximize the transfer of information, knowledge, and experience. The course will be intensive, practical, and highly interactive. The sessions will start by raising the most relevant questions and motivating everybody to find the right answers. The attendants will also be encouraged to raise more of their questions and to share in developing the right answers using their analysis and experience. There will also be some indoor experiential activities to enhance the learning experience. Course material will be provided in PowerPoint, with necessary animations, learning videos, and general discussions.

The course participants shall be evaluated before, during, and at the end of the course.

COURSE CERTIFICATE:

National Consultant Centre for Training LLC (NCC) will issue an Attendance Certificate to all participants completing a minimum of 80% of the total attendance time requirement.