
Explains why oil insulation improves transformer cooling and reduces size. Highlights mineral and synthetic oils used, with heat dissipated through radiators in power transformers.
Explore the main and conservator tanks, oil system with level indicator and breather (silica gel), and components such as tape changer, motor drive, bushings, core and yoke, oil release valve.
Examine transformer polarity using dot notation to identify additive and subtractive relationships between windings, and apply the right-hand rule to determine coil orientation and phase behavior.
Learn how to determine transformer polarity with two methods: the voltage method using S1/S2 and x1/x2 to identify additive or subtractive polarity, and a cell pulse method to verify polarity.
Explain the roles of the main tank and conservator in transformer oil systems, detailing oil expansion, vacuum considerations, and conservator configurations with bleeder, air balloon, and silica gel breeder.
Sealed tank transformers use nitrogen as a buffer to keep transformer oil sealed from the atmosphere, with corrugated radiators that absorb oil volume changes during temperature fluctuations.
Explore the breather in transformer conservators, where silica gel absorbs moisture and color shifts from blue to pink to signal replacement or regeneration, with bubbles indicating activity.
Radiators provide cooling by increasing transformer surface area; external radiators reduce heat without enlarging the tank, using natural oil circulation driven by temperature differences.
Explore how transformer oil circulates naturally: heated oil rises to the radiator, and cool oil returns to the tank, sustaining cooling during operation.
Use thermographic images to assess transformer radiator cooling, with top oil hotter (32–33°C) than bottom (24–26°C). Identify a blocked radiator by similar temperatures, requiring repair.
Dear Hi,
Trainer Introduction:
Your trainer brings over 21 years of experience in operation & maintenance, erection, testing, project management, consultancy, supervision, substation automation, SCADA, and commissioning. With a background spanning power plants, high voltage substations, and HVDC installations, he has worked with renowned organizations such as Siemens Saudi Arabia. He has been involved in over 20 high-voltage substation projects across Pakistan and Saudi Arabia.
His expertise encompasses a wide range of areas including protection systems, substation automation systems, design, testing, and commissioning of power generation systems, high voltage switchgear, protection relays, and control schemes. He has a proven track record of leading testing and commissioning teams for implementing electrical infrastructure projects for industrial clients, including steel and petrochemical industries.
Find below details of topics covered in this training.
Topics covered in Part 4:
85 Parts of Transformer
86 Why Oil is used in power transformers
87 Transformer Polarity
88 How to perform polarity test of transformer
89 Main Tank and Conservator Tank
90 Sealed Tank or hermetically sealed Transformer
91 Silica Gel and Breather
92 Function of Radiator
93 Direction of oil flow in radiator
94 Radiator Thermographic Image
95 Types of Radiators
96 Types of Cooling, Why Two ratings are given at name plate of transformer
97 Which factor is decisive for max loading capacity of transformer
98 What factor effect most for transformer aging
99 Effect of temperature on paper aging
100 Risks when wet transformer is overheated
101 What is soak test and why it is done
102 Why humming sound is observed in power transformer, Magnetostriction Effect
103 When humming sound of transformer is increased
104 Buchholz Relay
105 Where Buchholz relay is installed
106 Buchholz Relay Working Principle
107 Buchholz Functional Check
108 NO contacts of Buchholz Relay
109 Buchholz Bleeding and Test Point
110 Transportation and protection of Buchholz relay contact
111 Buchholz internal, view
112 Directional mark on Buchholz relay
113 Buchholz gas sampling device
114 Buchholz Manufacturer Operating Details
115 Sudden Oil Pressure Relay
116 Oil and Winding Temperature Indicator
117 Oil Level Indicator
118 Pressure Relief Device
119 Bushing of Transformer and Bushing Test Tap
120 Moisture is worst enemy of bushing
121 Periodical Check and maintenance of the bushing of transformer
122 HV Bushing Inspection glass
Regards
Elite Engineering