Installation and Commissioning of Transformer in 35KV Substation

The debugging of transformers is a vital part of the power system and is related to the safety and stability of the entire power grid. As power demand continues to grow and the scale of the power grid expands, transformer debugging becomes more complex and important. This article will introduce in detail the steps, precautions and solutions to common problems of transformer debugging to help relevant engineering and technical personnel better master this key technology. Scientific and reasonable debugging can not only ensure the normal operation of the transformer, but also extend its service life and improve the overall efficiency and reliability of the power system. Next, we will delve into the specific process and technical points of transformer debugging so that readers can learn from it in actual work.

Installation Content:

1. Foundation Preparation:

   • Inspect and prepare the transformer foundation.
   • Confirm the accuracy of foundation dimensions and location.

2. Transportation and Placement:

   • Transport and unload the transformer on-site.
   • Position and secure the transformer.

3. Attachment Installation:

   • Install radiators, fans, oil pumps, and other attachments.
   • Install the oil tank and fill with oil if needed.

4. Connection Work:

   • Connect high-voltage and low-voltage cables.
   • Connect the grounding system.

Commissioning Content:

1. Inspection and Testing:

   • Perform visual and physical inspections to ensure no damage.
   • Measure winding resistance and insulation resistance.

2. Electrical Testing:

   • Conduct transformer ratio tests.
   • Perform polarity and phase relationship tests.
   • Measure excitation current.
   • Conduct no-load and short-circuit tests.

3. Oil Sample Testing:

   • Sample and test insulating oil for moisture content and dielectric strength.

4. Pre-Operational Checks:

   • Ensure all connections are secure.
   • Verify the cooling system and protective devices are functioning properly.

5. Trial Operation:

   • Perform no-load trial operation before integrating into the grid.
   • Conduct load trial operation, gradually increasing load while monitoring transformer performance.

Installation Steps of Power Transformer

Before the installation of transformer, confirm the location and quantity of embedded parts according to the drawings, wiring according to the requirements of equipment installation, and necessary treatment of the foundation surface; check whether the shape size of transformer conforms to the drawings, confirm the net weight of transformer, measure the size of lifting position, make lifting rigging, and compact the running lines of equipment and crane; Walking track, etc.

When lifting transformers, special attention should be paid to protecting the overlapping pile heads and porcelain bottles of transformers. The necessary bandage protection should be carried out in the places where the crane contacts with the equipment to prevent the damage of the equipment. After the crane is stressed, check whether the center of gravity of the hook and the equipment is consistent, and adjust it. When the equipment is towed, the hand-pulled hoist installed in the transformer room is hung on the towing Jack rope at the bottom of the transformer. The transformer is slowly pulled into the transformer room along the track by the hand-pulled hoist, and the necessary cooperation is carried out by the crane during the towing process. After loosening the hook of the crane, the transformer is slowly dragged onto the track and put in place.

When installing transformers, special attention should be paid to check whether the high-voltage wire package is damaged or displaced, whether the high-voltage insulator is rubbed or damaged, and whether the humidity control devices, including humidity display instruments, are complete. During construction, no sundries are allowed to fall into the transformer barrel. The main iron core and shell are grounded reliably. The working grounding section should meet the requirements of the code, at least not less than the section of the main grounding line in the transformer substation. Transformers should be positioned in the direction of high and low voltage sides, and must not be mistaken. Transformer body should be placed horizontally. The tolerance error of installation horizontality is 2, and the tolerance error of perpendicularity is 1.5. According to the requirements of the transformer factory, the vibration isolator of the transformer is installed after the transformer is in place, and then the on-load voltage regulator, temperature measuring device, control box and other accessories are installed.

After the installation of transformer is completed, all fasteners and connectors should be checked before operation. Whether auxiliary devices such as wet control equipment attached to transformer are installed correctly or not. In order to check whether the transformer is in good condition, it is necessary to adjust the test according to the specifications and manufacturer's instructions. Each test is completed in accordance with the prescribed method. All instruments used in the test should be within the validity period of the test, and the test results should be recorded in the test report.

In short, the debugging of the transformer is a complex and important task, and it needs to be operated in strict accordance with the specifications and standards to ensure the safe and reliable operation of the transformer. Through the introduction of this article, we can see that transformer debugging is not only a technical job, but also a task that requires a high sense of responsibility and rigorous attitude. I hope this article can provide some valuable reference for technicians working on power systems, so that they can avoid common mistakes and improve the quality of their work in actual operations. In the future, with the advancement of science and technology and the increase in power demand, transformer debugging technology will continue to develop and improve, providing a stronger guarantee for the safe operation of the power system. Through continuous learning and accumulation of experience, technicians will be better able to cope with various challenges encountered during the commissioning process and promote the sustainable development of the power industry.

Series Testers for Substation Installation and commissioning:

The test items are required for 110kV/220kV substation acceptance and maintenance testing(with corresponding tester types):

Test Object	Testing Item	Tester Type
Cable	Cable AC Hipot Testing	JYCX	Details
	Cable Insulation Resistance Testing	JYM KYORITSU	Details
Transformer	Insulation Resistance of Winding	JYM KYORITSU	Details
	DC Leakage Testing in 1min	JYDHV	Details
	Winding Resistance Testing	JYR50S	Details
	Winding Deformation Testing	JYP	Details
	Turns Ratio Testing	JYT-A	Details
	AC Hipot Testing	JYCX	Details
	Short Circuit Impedance Testing	JYW6300	Details
	Dan Delta Testing	JYC	Details
	Oil Breakdown Voltage (BDV)Testing	JY6611	Details
	Oil Tan Delta Testing	GTD-61A	Details
Switchgear	Circuit Breaker/Disconnector Resistance	JYL-200B	Details
Relay	Relay Performance	JY7003G	Details
On-load	On-load Switchgear Testing	JYK-I	Details
	Tap Changer Dynamic Testing	JYK-I	Details
Instrument   Transformer	Current Transformer (CT)Testing	JYH-C	Details
	Potential Transformer (PT)Testing	JYH-C	Details
Surge Arrestor	Zinc Oxide Characteristics Testing	JY6800	Details
	1mA DC Reference Voltage	JYDHV	Details
Capacitor	Capacitor Current	JY6700	Details
	Capacitor Inductance	JY6700	Details
Ground Grid	Grounding Down Lead Earth	JYD	Details

Related Articles:

What Test Items are Required for 110kV/220kV Substation Acceptance and Maintenance Testing?

What Tests Must be Done before the Transformer Leaves the Factory?

Main Factors Affecting the Operating Life of Transformers

What is the Purpose of Measuring the DC Resistance of the Transformer Winding?

Points to note in transformer oil breakdown voltage (BDV) test

DC winding resistance tester with 500 times tests on a single charge -JYR9310