35kV power transformer

35kV Power Transformer

Product Technical Features

Product Technical Performance Characteristics: Three Low, One High, One None

The transformer features fully sealed maintenance-free, low loss, low noise, low temperature rise, high short-circuit withstand capability, no leakage, safe and reliable operation, etc. The on-load tap-changing power transformer can be unattended, remote controlled, remote monitored, and managed by a computer.

Product Design and Process Characteristics:

I. Core:

　　The transformer core adopts a step-lap and banding structure with internationally advanced technology. The core has no punching and continuous yoke, and the core pieces use high-quality cold-rolled grain-oriented silicon steel sheets; the core surface is brushed with solidified paint after forming. The clamping device is reasonable, reliable, and aesthetically pleasing; the advanced design and process of the core give the core great advantages in terms of performance and structure.

II. Windings:

In the design and manufacturing process of the product windings, the company's mature and advanced design, process, and manufacturing technologies are fully utilized to ensure the reliability and excellence of product performance.

1. Correctly select high-quality conductor and insulation materials, and reasonably select the width-thickness ratio of the conductors; the use of low conductor current density ensures a sufficiently large and reasonable cross-sectional area of the coil, reducing the radial tensile stress of the winding.

2. Insulation Materials: The coil conductor insulation of our company uses high-strength, high-density cable paper. During the design, the compression stress on the turn insulation is calculated according to the dynamic and steady-state characteristics of the transformer, effectively controlling and making the allowable compressive stress σmax of the coil pad match the allowable compressive stress of the cable paper, leaving sufficient margin.

3. Coils:

a. High and low voltage windings adopt a continuous and continuous structure, and the whole pressure plate is pressed tightly, which strengthens the axial mechanical strength of the winding;

b. Dennison paper is used for inter-coil insulation, enhancing the insulation strength between coil sections.

c. The high and low voltage windings adopt the domestically leading level of high and low voltage winding, the winding is compact, and the overall gapless set ensures the axial overall stability of the coil. The inner layer of the low voltage winding uses a 5mm formed insulation paper tube. It greatly improves the mechanical strength of the coil and the short-circuit withstand capability of the transformer.

4. The tank structure adopts a mature and excellent insulation structure, and field strength simulation calculation is used in the design calculation using a computer to carefully calculate the field strength at each point, and targeted strengthening measures are taken for weak links.

5. All coils are pre-pressed and vacuum-dried, assembled as a whole, and gapless, to improve the overall stability and rigidity of the transformer tank and good anti-sudden short-circuit capability.

6. The leads use copper foil or paper-wrapped cable soft connection.

III. Tank:

The tank uses a cylindrical tank, and the tank seal uses an inner and outer limit square structure to ensure that the sealing strip is in good condition. The sealing material is acrylic rubber, which has strong anti-aging ability and a long service life; the tank and oil reservoir are subjected to oil pressure sealing tests, and there is no leakage or damage for a sufficient duration.

Non-magnetic steel plates are welded in the local area of the tank to reduce the stray losses of the windings and prevent local overheating of the tank caused by magnetic leakage.

Vibration and flame are used to eliminate stress from the entire tank, and fluorescence leak detection and pressure tests are carried out for strict inspection to ensure no leakage.

IV. The main components of the transformer, such as bushings, radiators, on-load tap changers, temperature controllers (signal thermometers), seals, butterfly valves, vents, valves, etc., are all procured from designated suppliers. Our company selects high-quality products from well-known domestic manufacturers with production licenses issued by the Ministry of Machinery in accordance with the ISO9001 standard procurement procedures, and then strictly inspects and screens them after entering the factory. After long-term use, they can meet various technical requirements and operate stably and reliably.