Oil immersed high voltage test transformer for boosters

Summary. Yes, pro, DC withstand voltage or leak test:

1.Operation of DC withstand voltage or leakage test.

1) Unscrew out the short-circuit rod on the equalizing ball of the AC and DC test transformer, reliably connect the test transformer with the operation box (table), the transformer shell and the operating system must be reliably grounded, and the high-voltage tail x and the F end of the measuring winding must be reliably grounded.

2) The test personnel have a clear division of labor, clean up the site (if possible, the shield can be pulled), check whether the tested product is in power failure, grounding discharge, and strictly prevent the test voltage from being added to the working part.

3) After reviewing the connecting wires, send the power supply, slowly boost the voltage, pay close attention to the tested product, the test device, and the micro-ampere meter, once the breakdown, flickering and other abnormal phenomena are found, the voltage should be lowered immediately, the power supply should be cut off, the test product should be fully discharged, the cause should be identified, and the record should be recorded in detail.

4) After the test is completed, step down the voltage and cut off the power supply. Fully discharge the test product and the test device itself, and disassemble the equipment or replace the test product until the voltage divider reads zero.

The 200kVA oil-immersed transformer can be tested with DC withstand voltage.

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Yes, pro, DC withstand voltage or leak test: 1Operation of DC withstand voltage or leakage test(1) Unscrew out the short-circuit rod on the equalizing ball of AC and DC test transformer, reliably connect the test transformer with the operation box (table), the transformer shell and the operating system must be reliably grounded, and the high-voltage tail x and the F end of the measuring winding must be reliably grounded.

2) The test personnel have a clear division of labor, clean up the site (if possible, the shield can be pulled), check whether the tested product is in power failure, grounding discharge, and strictly prevent the test voltage from being added to the working part. (3) After reviewing the correctness of each connecting line, send the power supply, slowly boost the voltage, pay close attention to the tested product, test device, and micro-ampere meter, once the breakdown, flickering and other abnormal phenomena are found, the eggplant chain base should be immediately depressurized, cut off the power supply and tremble, fully discharge the sample, find out the reason, and record it in detail. 4) After the test is completed, step down the voltage and cut off the power supply.

Fully discharge the test sample and the test spinal test device itself until the voltage divider reads zero before disassembling the device or replacing the test sample.

The role of the transformer in the oil immersion test:

It is used in power systems, industrial and mining enterprises, scientific research departments, power generation maintenance departments, etc. to carry out dielectric strength tests under power frequency or DC high voltage for various high-voltage electrical equipment, electrical components, and insulating materials.

Extension of knowledge points:

The oil-immersed test transformer adopts a single-frame core iron core structure. The primary windings are wound around the core and the high-voltage windings are outside, and this coaxial arrangement reduces leakage flux and thus increases the coupling between the windings. Features:

1.The unique structure of axisymmetric unequal octagonal shell is adopted; It can output double high voltage.

2.The oil level in the oil tank is lower than the edge of the oil tank, which avoids oil leakage.

3.The binding posts are on the lid of the case, which avoids collisions and improves mechanical and electrical performance.

4.The product has the characteristics of compact structure, stable electrical performance, sufficient capacity, small size, light weight, easy use and maintenance.

Oil-immersed test transformers.

Product name: oil-immersed test transformer, oil-immersed test transformer, oil-immersed test transformer manufacturer, oil-immersed test transformer.

**, oil-immersed test transformer**, oil-immersed test transformer selection, oil-immersed test transformer model, oil.

Immersion test transformer principle.

Product introduction: Oil-immersed test transformer, also known as booster, is a power generation and power supply bureau preparation, various electrical products and insulation tools.

Necessary equipment for the electrical strength test of materials.

YDJ (Z) series oil-immersed test transformer is produced according to the standard of "Test Transformer" of the Ministry of Mechanical and Electrical Engineering on the basis of a large number of improvements on the basis of the original similar products. This series of products has the characteristics of small size, light weight, compact structure, complete functions, strong versatility and easy use. Oil-immersed test transformer is especially suitable for power systems, industrial and mining enterprises, scientific research departments, etc. to carry out dielectric strength test under power frequency or DC high voltage for various high-voltage electrical equipment, electrical components, and insulating materials, and oil-immersed test transformer is an indispensable important equipment in high-voltage test.

The oil-immersed test transformer is produced in strict accordance with international and national standards and industry regulations, and has passed the testing of national, provincial and municipal electric power research institutes, metrology centers and electric power authorities, and has fully passed the ISO9001 international quality management system certification, the People's Republic of China manufacturing measuring instrument license, GB T19001-2008 quality management system requirements, GB T24001-2004 environmental management system requirements, and GB T28001-2011 Occupational Health and Safety Management System Requirements.

1. The new 10kV oil-immersed transformer has a power frequency AC test withstand voltage (AC), and the high-voltage side is 35kV. If the low-voltage side is 400V, the power frequency AC test withstand voltage is 5000V.

2. The new 10kV dry-type transformer has two kinds of power frequency test withstand voltage: 28kV according to indoor requirements and 35kV according to outdoor requirements. However, more dry transformer manufacturing plants are designed and manufactured according to the 35kV withstand voltage level.

The low-voltage 400V side is still 5000V.

Oil-immersed test transformers are widely used in electric power systems, industrial and mining enterprises and other departments, and it has the same type of gas-filled test transformers, dry-type test transformers, let's see what are the disadvantages and advantages of oil-immersed transformers.

Advantages and disadvantages of oil-immersed test transformers.

Compared with the same type, the oil-immersed test transformer has the same internal winding, the difference is that the material or medium is different, the dry-type transformer is epoxy resin insulation, the advantage is that the weight is relatively light, but the voltage is limited, the maximum voltage can only be 120kV, in addition, the epoxy resin is easy to break after being impacted, the gas-filled transformer is insulated with SF6 gas, high precision, light weight, relatively expensive, generally used as a standard megafiber voltage by the metrology institute and the inspection institute, In addition to the disadvantages of the oil-immersed test transformer, it is also an advantage.

The oil-immersed test transformer uses oil as the insulating medium, high voltage, large capacity, metal shell, durable, and much cheaper under the same capacity, in addition, the oil-immersed transformer is cheap and fast to maintain, once the wire pack fails, only need to unscrew the shell screw, remove the insulating oil, and replace it with a new wire pack to inject new oil, which is much faster than the dry-type and gas-filled test transformer.

The test transformer has the characteristics of high voltage, small capacity, large transformation ratio, continuous working time, thick insulation layer, and grounding at one end of the high-voltage winding.

When choosing an oil-immersed test transformer, the following points are mainly considered:

1) Select the voltage. According to the requirements of the test product, the test transformer with appropriate voltage is selected firstly, so that the rated voltage of the high-voltage side of the test transformer is higher than the test voltage US of the tested product, that is, un>us. Secondly, it is necessary to check whether the low-voltage side voltage required by the test transformer can match the on-site power supply voltage and voltage regulator.

2) Select the current. The rated output current of the test transformer in should be greater than the current required by the test product, i.e., in>is. The current required by the test sample can be estimated according to its capacitance, is=us w cx, where cx includes the test capacitance and additional capacitance.

3) Select the capacity. According to the rated current and rated voltage of the output of the test transformer, the capacity of the test transformer can be determined, that is, p=unin.

According to the national ministerial standards, the voltage level of China's test transformer is kv, etc.; Capacity levels are KVA and so on.

The transformer is the core equipment of the power system. The quality of its state is directly related to the stable operation of the power system, so it is necessary to conduct regular insulation preventive tests in order to track its state changes and ensure its safe, healthy and stable operation. The role of transformers in the power system is to transform the voltage to facilitate the transmission of power.

After the voltage is boosted by the step-up transformer, the line loss can be reduced, the economy of power transmission can be improved, and the purpose of long-distance power transmission can be achieved. The step-down transformer can turn the high voltage into the voltage required by the user at all levels to meet the needs of the user, and is the core equipment of the power system. The quality of its state is directly related to the stable operation of the power system, so it is necessary to conduct regular insulation preventive tests in order to track its state changes and ensure its safe, healthy and stable operation. At the same time, the transformer manufacturer should also carry out factory tests on the transformers it manufactures to ensure product quality.

In addition, the transformer installation unit, after the completion of the transformer installation project, should also carry out the handover test to meet the requirements of operation. The transformer is a very important equipment in the power system, and its operating state directly affects the safe operation of the system. The main functions of the transformer are:

voltage conversion; Current conversion, impedance conversion; Isolation; voltage regulation (magnetic saturation transformer); autotransformers; High-voltage transformers (dry-type and oil-immersed), etc., the commonly used core shapes of transformers generally include E type and C type core, XED type, ED type CD type. In its most basic form, a transformer consists of two sets of coils wound with wires wound and inductively weighed together with each other. When an alternating current (with a known frequency) flows through one of the coils, an alternating voltage of the same frequency is induced in the other coil, and the magnitude of the induced voltage depends on the degree of coupling and cross-linking of the two coils.

The role of transformers in the power system is to transform the voltage to facilitate the transmission of power. After the voltage is boosted by the step-up transformer, the line loss can be reduced, the economy of power transmission can be improved, and the purpose of long-distance power transmission can be achieved. The step-down transformer can turn the high voltage into the voltage required by the user at all levels to meet the needs of the user, and is the core equipment of the power system. The quality of its state is directly related to the stable operation of the power system, so it is necessary to conduct regular insulation preventive tests in order to track its state changes and ensure its safe, healthy and stable operation.

At the same time, the transformer manufacturer should also carry out factory tests on the transformers it manufactures to ensure product quality. In addition, the transformer installation unit, after the completion of the transformer installation project, should also carry out the handover test to meet the requirements of operation. This is the three links of transformer from manufacturing to use.

Therefore, it is very important and indispensable to carry out power transformer testing. The purpose of the transformer test is to obtain its performance data, which is used to determine whether the transformer is qualified or not, and provide it to the user. When designing transformers, the relevant standards and technical requirements must be followed.

Therefore, the results of the trial should be relevant. Different standards and technical requirements have different test methods and results.

The transformer withstand voltage test (external high voltage test) is mainly to check whether the main insulation of the transformer is qualified, that is, the insulation between the primary coil and the secondary coil, between them and the core and shell. If it is not qualified, it will not only endanger the damage of the transformer itself and other connected electrical installations, but also cause danger to the equipment and personnel who use electricity.

The withstand voltage test is to use the frequency test transformer to add a certain AC high voltage, which lasts for one minute, if the insulation does not break down or the leakage current does not exceed a certain value, it is qualified. For example, oil-immersed power transformer, 10kV, factory test and handover test are kV respectively.

Resources.

The higher the transformer oil temperature, the faster the transformer's oil will age.

The current operating procedures are generally said to be the 10-degree rule.

That is, the transformer operates for a long time in excess of the "temperature rise limit", and the service life of the transformer is shortened by half for every 10 increases. However, if the temperature rise does not exceed the limit, there is generally no problem, and there is no problem with normal temperature fluctuations with load.

Generally speaking, the higher the temperature, the lower the oil pressure, and the higher the temperature of the oil is normal, the thinner it is, and the insulation performance is reduced.