4000 kVA 3 Phase Pad Mounted Transformer-24.94/0.6 kV | Canada 2024

Durable performance, professional quality – Three-Phase Pad-Mounted Transformer, making power smarter!

01 General

1.1 Project Description

This 4000 kVA Pad mounted transformer was delivered to Canada in 2023. The rated power of the 3 phase pad mounted transformer is 4000 kVA, with the primary voltage 24.94GRDY/14.4 kV to secondary voltage 0.6y/0.347 kV. The connection group is YNyn0, the cooling is ONAN. The transformer body, high-voltage load switch, fuse and other components are placed together in the transformer tank, because of immersion in oil, the component volume is greatly reduced, the structure is more compact, easy to install and flexible. Fully insulated, fully sealed structure, safe and reliable, easy to operate, maintenance-free. Widely used in residential areas, high industry centers, factories and mining enterprises, airports, stations, schools and other places.

SCOTECH ensure each one of our delivered transformers had passed the full acceptance test and we remain 0 fault rate record for more than 10 years so far, oil immersed power transformer is designed in accordance with IEC, ANSI and other major international standards.

1.2 Technical Specification

4000 kVA 3 phase pad mounted transformer specification and data sheet

1.3 Drawings

4000 kVA 3 phase pad mounted transformer diagram drawing and size.

02 Manufacturing

2.1 Core

The transformer core is made of 0.23 to 0.35 mm thick cold-rolled gray-oriented magnetic silicon steel sheet. The whole roll of cold-rolled gray-oriented magnetic silicon steel sheet is cut vertically to the required width along the direction of the silicon steel sheet in the automatic hob processing line, and then the strip of a certain width is cut horizontally into transformer iron chips of various specifications and sizes. Generally, it is 45 degrees in the direction of the length of the silicon steel sheet. The large transformer core is stacked on the stacked platform for stacking operation, generally two pieces of stacking, at present in the power transformer, generally use the miter slit core, with the progress of transformer manufacturing technology, miter slit core seams are divided into staggered joints and stepped joints. In the type of staggered joints, it is generally two overlapping joints, which is a two-level staggered oblique seam stacking method; In the class seam type, it is generally 5 or 6 pieces for a cycle. In order to improve the no-load characteristics of the transformer, the laminated joints are staggered up and down and left and right, so as to form a multi-level joint form of the iron core, which is called step lap joint. The number of components of the stepping lap core is generally in the form of 3, 5 and 6 levels. With the increase of transformer capacity, the core of the 6-step lap joint is currently used, and the flake types of the core lamination are also increasing due to the increase in the number of steps.

2.2 Winding

Transformer winding converts one (numerical) voltage to another (same frequency) voltage, in this way, the winding as the core part of the transformer, according to the rated power and use of the transformer, using different types of winding. One of the most commonly used winding types, spiral – Spiral windings are usually spiral in shape and are primarily used as low-voltage winding, but the complexity of this winding increases as the current to be handled becomes larger. High currents require a large cross-sectional area, so eddy current losses also increase. For this reason, it is necessary to use two or more conductors connected in parallel to reduce eddy current losses. Today’s practice is to use continuous cross-transposition winding (with as little circulation as possible) for high pressure, and a series of metal blocks are formed by winding round conductors into different layers and loops. Pie windings are used in transformers with high power ratings, where the disks are made of spiral conductors in the same position. This alternate disk is connected in series through internal and external intersections. The overlapping windings have a unique construction, where the high and low voltage windings are located in the same magnetic channel, and each high voltage unit is located in the middle of the two low voltage units. As a result, the leakage flux is greatly reduced.

2.3 Tank

3 phase pad mounted transformer tank is made of high quality stainless steel plate, with an anti-corrosion design and special spray painting treatment. The film thickness is 0.3mm, the color is full, the corrosion resistance is strong, the anti-ultraviolet ability is strong, and the color is highly coordinated with the environment, which is suitable for various harsh environments.

2.4 Final Assembly

The structure of the 3 phase pad mounted transformer is divided into two parts, the front is the wiring cabinet, the wiring cabinet includes high and low voltage terminals, high voltage load switch, plug-in fuse, high pressure tap changer operating handle, oil taste meter, oil temperature meter, etc.; The rear is the oil box and heat sink, transformer winding, iron core, high voltage load switch, plug-in fuse are in the tank body. Load switches, fuses, and transformers are immersed in transformer oil. Install the terminal on the housing, put the assembled iron core into the oil tank, fix the screws after the iron core is put in, and install the high voltage fuse. After all the above steps are completed, fill the oil tank.

03 Testing

Insulation test: test the insulation performance of the transformer, including dielectric strength test and insulation resistance test.

High temperature test: test the working performance and stability of the box under high temperature environment.

Load test: Test the performance of the box under rated load, including voltage stability, short-term overload capacity, etc.

Short circuit test: test the working performance and safety performance of the box under short circuit.

Dielectric loss test: Test the loss of the internal medium of the box to determine its loss power and loss factors.

Electrical characteristics test: including box-varying voltage ratio test, no-load loss test, short-circuit impedance test, etc.

04 Packing and Shipping

05 Site And Summary

Thank you for your interest in our 3 phase pad mounted transformer! With its exceptional performance, reliable safety features, and outstanding energy efficiency, this product is widely applicable in industrial, commercial, and utility sectors, providing a stable and efficient solution for your power system. We are committed to delivering high-quality products and attentive service, and we look forward to working with you to create a brighter future in the power industry. For more information or technical support, please feel free to contact us!