Transformer Differential Protection Calculations SEL 787

Power Transformer Protection & Commissioning: A Comprehensive Course

Learn the intricacies of power transformer protection and commissioning with an expert who brings over 21 years of experience in operation & maintenance, erection, testing, and project management. This course delves into critical aspects of electrical infrastructure, drawing on real-world experience with organizations like Siemens Saudi Arabia and involvement in over 20 high-voltage substation projects across Pakistan and Saudi Arabia.

Expert Instructor: Your trainer possesses deep expertise in substation automation, SCADA, commissioning, protection systems, high voltage switchgear, protection relays, and control schemes. He has a proven track record leading testing and commissioning teams for industrial clients in sectors like steel and petrochemical industries.

SEL-787 Relay Deep Dive:

• Differential Protection: Master the SEL-787 relay and its three differential elements (87R-1, 87R-2, and 87R-3).
• Operate (IOP) & Restraint (IRT) Quantities: Understand how these quantities are calculated from winding input currents for reliable protection.
• Characteristic Settings: Learn to configure relay characteristics using single-slope or dual-slope, variable-percentage differential characteristics. Understand the significance of O87P, SLP1, IRT, IRS1, and SLP2 settings.
• TAP Scaling: Explore how TAP scaling utilizes transformer MVA rating to convert secondary currents into per-unit values, ensuring accurate calculations.

Practical Application: Power Transformer Protection Settings

This course provides hands-on experience with a 26MVA power transformer, including:

• Transformer Specifications: Detailed analysis of ONAN/ONAF cooling, Dyn11 vector group, rated voltages (HV & LV), full-load currents, rated power, impedance, and tap changer type.
• Calculations: Perform essential protection settings calculations for:
  • Power Transformers
  • Full Load Amperes
  • Short Circuit MVA
  • Short Circuit Current (HV & LV sides)
  • Short Circuit MVA & Percentage Impedance Relationship
  • Magnitude & Phase Angle Error and Compensation
  • CT Error and Compensation
  • Operating & Restraining Currents
  • Pickup Current Calculations
  • TAPN Calculations
  • Phase Angle Compensation Settings
  • Slope 1 & 2 Calculations
  • Harmonics Blocking Calculations

Enhance your skills in electrical power systems protection and transformer protection with this comprehensive course.