How is the transformer capacity calculated?

Conventional method: the transformer capacity should be selected according to the calculated load, and the load rate of a single transformer with stable load power supply is generally about 85. Namely:

s/se。where s is the calculated load capacity (kva), se is the transformer capacity (kva), and is the load rate (usually 80 90).

Calculate the total power of three phases: 11kw x 33kw of 3 phases (total power of transformer three phases).

Three-phase total power, which is the most important step, more than 90% of the power factor of transformers sold on the market.

only, so need to divide by the power factor.

33kw = total transformer power).

need to purchase the transformer power), then choose a 50kva transformer when buying.

The principle of a transformer.

A transformer is a device that uses the principle of electromagnetic induction to change the alternating voltage, and the main components are the primary coil, the secondary coil and the core (core).

In electrical equipment and wireless circuits, it is often used as voltage increase, impedance matching, safety isolation, etc. In the generator, whether the coil movement passes through the magnetic field or the magnetic field moves through the fixed coil, the electric potential can be induced in the coil.

In both cases, magnetic flux.

The value of is constant, but the amount of magnetic flux of the intersecting chain with the coil changes, which is the principle of mutual induction. A transformer is a device that uses electromagnetic mutual induction to transform voltage, current, and impedance.

According to the "Electric Power Engineering Design Manual", the transformer capacity should be selected according to the calculated load, and the load rate of a single transformer with stable load power supply is generally about 85. i.e.: =s se where:

S ——— calculate load capacity (kVA), SE ——— transformer capacity (kVA), load factor (usually 80 90).

Add the load power of phase A, phase B, and phase C independently of each phase, for example, the total power of phase A is 10kW, the total power of phase B is 9kW, and the total power of phase C is 11kW, and the maximum value is 11kW. (The power of each device in the single phase is calculated according to the maximum value on the nameplate, and the power of the three-phase device divided by 3 is equal to the power of each phase of the device).

Precautions for the use of transformers.

Prevent transformer overload operation. If it is overloaded for a long time, it will cause the coil to heat up, make the insulation gradually age, and cause a short circuit between the box, a short circuit between phases or a short circuit to the ground and the decomposition of oil.

Ensure the quality of insulating oil: In the storage, transportation or operation and maintenance of transformer insulating oil, if the oil quality is poor or impurities and moisture are excessive, the dielectric strength will be reduced. When the dielectric strength is reduced to a certain value, the transformer will be short-circuited and cause sparks, arcing or dangerous temperatures.

Therefore, the oil quality of the transformer should be tested regularly during operation, and the unqualified oil should be replaced in time.

The above content refers to Encyclopedia - Rated Capacity of Transformers.

Start by selecting the rated voltage of the transformer. The voltage on the high-voltage side is equal to the grid-connected grid voltage, and the voltage on the low-voltage side is 10% or 5% higher than the grid voltage on the low-voltage side; Select the rated capacity.

Calculate the size of the load carried by the transformer. If there are two transformers, the capacity of each transformer can be selected at 70% of the maximum combined load, and one transformer is considered based on the total load, with an appropriate margin.

The capacity of the transformer is the product of its rated voltage and rated current, the unit is VA, and the large capacity can also be KVA or MVA.

Although we know that the voltage is dropped from 220V to 9V through the transformer, we also need to know what the rated current of the transformer is at 220V. Use 220 rated current and divide by 9, which is the rated current value that the transformer can output at 9V

The unit of power transformer capacity is kva, i.e., apparent power. Most electrical loads are inductive loads, and their apparent power is equal to the vector sum of active and reactive power. Therefore, the apparent power of the inductive load is greater than the active power.

If the transformer selects active power, the apparent power of the inductive load must be greater than the capacity of the power transformer, and the load current must exceed the allowable value of the transformer. Therefore, the inductive load must use the apparent power to select the transformer.

The capacity of the transformer is kva, and the actual power of the electrical equipment used is kw, and the general power factor can be taken according to the actual situation).

Then the transformer capacity is the power of the electrical equipment used, the best operating state of the transformer is 65-75% loaded, if all the equipment is 600kw, the selected transformer capacity is 600 08 kva

Why is China's transformer capacity standard increasing by multiple? Today is a long time to see.

First of all, it is necessary to investigate the power supply voltage of the place of electricity, the actual electricity load of the user and the conditions of the place, and then select one by one with reference to the technical data marked by the nameplate of the transformer, generally from the transformer capacity, voltage, current and environmental conditions, wherein the capacity selection should be determined according to the capacity, nature and use time of the user's electrical equipment, so as to select the transformer capacity.

During normal operation, the electrical load of the transformer should be about 75 90% of the rated capacity of the transformer. If the actual load of the transformer is measured to be less than 50% during operation, the small-capacity transformer should be replaced, and the large-capacity transformer should be replaced immediately if it is greater than the rated capacity of the transformer.

At the same time, in the selection of transformers, the voltage value of the primary coil of the transformer is determined according to the line power supply, and the voltage value of the secondary coil is selected according to the electrical equipment, and it is best to choose the low-voltage three-phase four-wire power supply. This provides both power and lighting at the same time.

For the selection of current, it should be noted that the load can meet the requirements of the motor when the motor is started (because the starting current of the motor is 4 7 times larger than that when the motor is sinking).

Transformer capacity calculation method:

Start by selecting the rated voltage of the transformer. The voltage on the high-voltage side is equal to the voltage of the connected grid, and the voltage on the low-voltage side is 10% or 5% higher than the voltage of the low-voltage grid (depending on the voltage level and impedance voltage of the transformer); Rated capacity selection.

Calculate the size of the load carried by the transformer (the maximum comprehensive load is required to be counted, and the active load kw value is converted to the apparent power kva), if it is two transformers, then the capacity of each transformer can be selected according to 70% of the maximum comprehensive load, and a transformer should be considered according to the total load, and leave an appropriate margin. Other brand-name parameters can be properly considered in combination with transformer products.

For example: Choose a 35 10kV transformer. Assuming that the maximum load is 3500kw, the power factor is, choose two transformers, capacity s=, you can choose a transformer of 3150kva, and the voltage ratio is 35kv. Then select the model number from the product catalog.

KVA is Apparent Power.

The unit of kw is the unit of power, and the apparent power * power factor.

Active power, if the power factor of the circuit is equal to 1, then 100kva = 100kw.

Kilovolt amps.

KVA), generally refers to the power system.

The rated capacity of medium power equipment (such as transformers, motors, etc.).

The unit where the rated capacity represents the guaranteed value of the output power under the rated working conditions, the apparent power for the transformer, and the active power for the motor.

First, select the transformer.

The rated voltage of the BAI device. The voltage of the high-voltage side is equal to the voltage of the connected power grid, and the voltage of the low-voltage side is 10% or 5% higher than that of the low-voltage capacitor network (depending on the voltage level and impedance voltage of the transformer); Rated capacity selection.

Calculate the size of the load carried by the transformer (the maximum comprehensive load is required to be counted, and the active load kw value is converted to the apparent power kva), if it is two transformers, then the capacity of each transformer can be selected according to 70% of the maximum comprehensive load, and a transformer should be considered according to the total load, and leave an appropriate margin. Other brand-name parameters can be properly considered in combination with transformer products.

For example: Choose a 35 10kV transformer. Assuming that the maximum load is 3500kw, the power factor is, choose two transformers, capacity s=, you can choose a transformer of 3150kva, and the voltage ratio is 35kv. Then select the model number from the product catalog.

The power of the transformer depends on the core material.

The size of the section of the DU material and the core. Generally, the magnetic flux of the iron core is 800

DAO1500 Gauss. The current transformer generally has a magnetic flux of more than 1200 gauss, and the high magnetic flux can reduce the volume of the transformer.

If you want to determine the power of the transformer, you have to measure the cross-sectional area of the core, otherwise no one can know its power.

If you want to talk about power calculations, it's a simple thing:

Voltage * Current * Power Factor = Power.

This refers to the situation when the transformer is operating at full capacity.

If the original coil of the transformer is marked with voltage and current, just multiply them and do not need to multiply by the power factor.

If the secondary coil is marked with voltage and current, and there is more than one set of outputs, then each set of voltage and current must be multiplied separately and the resulting power can be added.

1495kw power bai

Is it the total equipment power? This is called the loading capacity. Usually take the simultaneous zhi rate, the theoretical DAO power factor.

If the negative load fluctuates greatly, and there is no capacity increase in the near future, a transformer of 1250kVA can be selected.

If the load is stable and it is possible to increase the capacity, a 1600kVA transformer can be selected.

Conventional Method:According to the "Electric Power Engineering Design Manual", the transformer capacity should be selected according to the calculated load, and the load rate of a single transformer with stable load power supply is generally about 85. Namely:

S SE where: S ——— Compute Load Capacity (KVA); SE ——— transformer capacity (KVA); Load rate (usually 80 90).

Calculate the maximum power of each phase of the load: add the load power of phase A, phase B, and phase C independently of each phase, for example, the total power of phase A is 10kW, the total power of phase B is 9kW, and the total power of phase C is 11kW, and the maximum value is 11kW. (Note:.)

(The power of each device in the single phase is calculated according to the maximum value on the nameplate, and the power of the three-phase device divided by 3 is equal to the power of each phase of the device).For example: the total power of phase C load = 300W x 10 computers) + (2KW x 4 air conditioners) = 11KW.

Calculate the total power of three phases: 11kw x 33kw of 3 phases (total power of transformer three phases).Three-phase total power, this is the most important step, more than 90% of the transformers currently sold on the market have only a power factor, so it needs to be divided by the power factor.

33kw = total transformer power), = transformer power that needs to be purchased), then choose a transformer of 50kva when purchasing.

A transformer is a device that uses the principle of electromagnetic induction to change the alternating voltage, and the main components are the primary coil, the secondary coil and the iron core (magnetic core). The main functions are: voltage conversion, current conversion, impedance conversion, isolation, voltage regulation (magnetic saturation transformer), etc.

Transformers can be divided into distribution transformers, power transformers, fully sealed transformers, combined transformers, dry-type transformers, oil-immersed transformers, single-phase transformers, electric furnace transformers, rectifier transformers, reactors, anti-interference transformers, lightning protection transformers, box-type substation test transformers, corner transformers, high-current transformers, excitation transformers, etc.

Transformer is the basic equipment for power transmission and distribution, which is widely used in industry, agriculture, transportation, urban communities and other fields. There are about 17 million transformers in operation in China, with a total capacity of about 11 billion kVA. The transformer loss accounts for about 40% of the power loss of transmission and distribution, and has great potential for energy saving.

Summary. Hello dear, happy to answer your <>

How is the transformer capacity calculated Yes That is, the rated load of the transformer, it is calculated as: s=u*i* 3 s: refers to the transformer capacity u:

Refers to the rated voltage of the transformer, refers to the line voltage i: refers to the rated current according to this formula.

How is the transformer capacity calculated?

Dear, hello with a smile, I'm glad that Zheng Nian answered your <>

How is the capacity of the transformer jack calculatedYes, that is, the rated load of the transformer, it is calculated as: s=u*i* 3 s: refers to the transformer capacity u:

Refers to the rated voltage of the transformer, refers to the line voltage i: refers to the rated current according to this formula.

How big is the transformer needed for a load of 4,000 kW, the voltage is 10 kV on the high voltage side, and about 400V on the low voltage side.

5000kVA transformer.

How to calculate it.

This kind of guy who eats is inconvenient to tell you.

Dear, I am glad to answer for you: How is the transformer capacity calculated? According to the "Power Engineering Design Manual", the transformer capacity should be selected according to the calculated load, and the load rate of a single transformer for stable load power supply is generally about 85%.

i.e.: s se where: s - compute load capacity (kva); SE ——— transformer capacity (KVA); Load factor (usually 80% 90%) Calculate the maximum power per phase of the load:

Add the load power of phase A, phase B and phase C separately, for example, the total power of phase A load is 10kW, the total power of phase B load is 9kW, and the total power of phase C load is 11kW, and the maximum value is 11kW. (Note: The power of each device in the single phase is calculated according to the maximum value on the nameplate, and the power of the three-phase equipment is divided by 3, which is equal to the power of each phase of the equipment

The total power of phase C load = (computer 300w x 10 sets) + (air conditioner 2kw x 4 sets) = 11kw