Dry-type Distribution Transformers Solution for Public Building

This article describes in detail the selection of dry-type distribution transformers in the process of configuring the public building power grid.

From the economic considerations of long-term operation, more efficient and energy-saving dry-type distribution transformers should be used first.

Daelim is a transformer manufacturer with 16 years of experience in the design and production of dry-type distribution transformer. It can provide transformer solutions for your public building grid.

Daelim’s professionalism and efficiency have been recognized by customers in dozens of countries and regions around the world.

DAELIM’s dry-type distribution transformer has obtained IEEE, ANSI, CSA, and IEC certifications.

Can provide the most professional transformer solutions for your power grid construction.

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Why look for energy-saving distribution transformers for public buildings?

Public buildings are a high-density area of building energy consumption at this stage. Public building area accounts for less than 4% of the total urban building area, but its energy consumption accounts for 22% of the total building energy consumption.

Public buildings are densely populated, and power dry-type distribution transformersare important equipment for public buildings. The installed density is several times higher than that of other buildings, and dry-type distribution transformer are mostly used.

When designing the power supply and distribution of public buildings, it is necessary to analyze the safety, economy, and energy saving, and finally determine the dry-type transformer model.

Learn more about it:Dry-type Transformer Model List

What is the efficiency of a dry-type transformer?

Due to the continuous improvement of magnetic materials, the no-load loss value of dry-type distribution transformer is constantly adjusted down.

But so far, the conductivity improvement of copper has only increased by 3%, unlike the magnetic material that has undergone four generations of improvement in permeability.

Therefore, in the later period, the latest energy-saving models only reduce no-load loss, and their load loss has not changed.

This is because under the current material, design, and technological level, to reduce load loss, the only way to greatly increase the use of winding copper wire, resulting in increased dry-type transformer costs, increased volume, and lower cost performance.

Daelim uses the most advanced technology on the market to produce a three-phase epoxy dry-type transformer.

This dry-type transformer greatly reduces no-load loss while reducing load loss. Save you a lot of electricity, save energy and money.

See more:What is the no load losses of transformer？What is the short-circuit loss of the transformer

10kv class 9 dry-type non-excitation voltage regulating distribution transformer no-load loss and load loss value

Rated Capacity（kVA）	No-load loss (W)	Load loss/W			Short circuit resistance (%)
Rated Capacity（kVA）	No-load loss (W)	B（100℃)）	F（120℃)）	H（145℃)）	Short circuit resistance (%)
30	220	710	750	800	4
50	310	990	1060	1130
80	420	1370	1460	1560
100	450	1570	1670	1780
125	530	1840	1960	2100
160	610	2120	2250	2410
200	700	2510	2680	2870
250	810	2750	2920	3120
315	990	3460	3670	3930
400	1100	3970	4220	4520
500	1310	4860	5170	5530
630	1510	5850	6220	6660
630	1460	5940	6310	6750	6
800	1710	6930	7360	7880
1000	1990	8100	8610	9210
1250	2350	9630	10260	10980
1600	2760	11700	12400	13270
2000	3400	14400	15300	16370
2500	4000	17100	18180	19460
1600	2760	13000	13700	14500	8
2000	3400	15900	16900	18000
2500	4000	18800	20000	21400

Related to it is:Selection of 10kv Distribution Transformer Protection Configuration Mode

No-load loss and load loss value of 10kv class 10 dry-type non-excitation voltage regulating distribution transformer

Rated Capacity（kVA）	No-load loss (W)	Load loss/W			Short circuit resistance (%)
Rated Capacity（kVA）	No-load loss (W)	B（100℃)）	F（120℃)）	H（145℃)）	Short circuit resistance (%)
30	190	670	710	760	4
50	270	940	1000	1070
80	370	1290	1380	1480
100	400	1480	1570	1690
125	470	1740	1850	1980
160	540	2000	2130	2280
200	620	2370	2530	2710
250	720	2590	2760	2960
315	880	3270	3470	3730
400	980	3750	3990	4280
500	1160	4590	4880	5230
630	1340	5530	5880	6290
630	1300	5610	5960	6400	6
800	1520	6550	6960	7460
1000	1770	7650	8130	8760
1250	2090	9100	9690	10370
1600	2450	11050	11730	12580
2000	3050	13600	14450	15560
2500	3600	16150	17170	18450
1600	2450	12280	12960	13900	8
2000	3050	15020	15960	17110
2500	3600	17760	18890	20290

No-load loss and load loss value of 10kv class 11 dry-type non-excitation voltage regulating distribution transformer

Rated Capacity（kVA）	No-load loss (W)	Load loss/W			Short circuit resistance (%)
Rated Capacity（kVA）	No-load loss (W)	B（100℃)）	F（120℃)）	H（145℃)）	Short circuit resistance (%)
30	170	670	710	760	4
50	240	940	1000	1070
80	330	1290	1380	1480
100	360	1480	1570	1690
125	420	1740	1850	1980
160	480	2000	2130	2280
200	550	2370	2530	2710
250	640	2590	2760	2960
315	790	3270	3470	3730
400	880	3750	3990	4280
500	1040	4590	4880	5230
630	1200	5530	5880	6290
630	1170	5610	5960	6400	6
800	1360	6550	6960	7460
1000	1590	7650	8130	8760
1250	1880	9100	9690	10370
1600	2200	11050	11730	12580
2000	2740	13600	14450	15560
2500	3240	16150	17170	18450
1600	2200	12280	12960	13900	8
2000	2740	15020	15960	17110
2500	3240	17760	18890	20290

Learn more:10kV Transformer Condition Inspection and Failure Analysis

No-load loss and load loss value of 10kv class amorphous alloy iron core non-excitation voltage regulating dry-type distribution transformer

Rated Capacity（kVA）	No-load loss (W)	Load loss/W			Short circuit resistance (%)
Rated Capacity（kVA）	No-load loss (W)	B（100℃)）	F（120℃)）	H（145℃)）	Short circuit resistance (%)
30	70	670	710	760	4
50	90	940	1000	1070
80	120	1290	1380	1480
100	130	1480	1570	1690
125	150	1740	1850	1980
160	170	2000	2130	2280
200	200	2370	2530	2710
250	230	2590	2760	2960
315	280	3270	3470	3730
400	310	3750	3990	4280
500	360	4590	4880	5230
630	420	5530	5880	6290
630	410	5610	5960	6400	6
800	480	6550	6960	7460
1000	550	7650	8130	8760
1250	650	9100	9690	10370
1600	760	11050	11730	12580
2000	1000	13600	14450	15560
2500	1200	16150	17170	18450
1600	760	12280	12960	13900	8
2000	1000	15020	15960	17110
2500	1200	17760	18890	20290

10KV Class Three Phase Epoxy-resin Dry-type Transformer no-load loss and load loss value

Rated Capacity（kVA	No-Load loss/W	On Load loss/W	Short circuit resistance (%)
50	270	990	4
100	400	1570
160	540	2120
200	620	2520
250	720	2750
315	880	3460
400	970	3980
500	1160	4880
630	1340	5870
800	1520	6950
1000	1760	8120	6
1250	2090	9690
1600	2450	11730
2000	3320	14450
2500	4000	17170

Search now:2021 Ultimate Dry Type Cast Resin Transformer Guide

Transformer production process - tank

Transformer production process -Test

Transformer production process - Active Part And Assembly

Transformer production process - winding

20KV Class Three Phase Epoxy-resin Dry-type Transformer (1)

transformer drying oven

Daelim's certification

What is the power loss of a dry-type transformer?

1. Power loss analysis of distribution dry-type transformers

The power loss of a dry-type transformer is composed of active and reactive power.

The active power loss of a dry-type transformer consists of the following two parts:

One part is the active power iron loss produced by the main magnetic flux in the dry-type transformer core. The iron loss has nothing to do with the load of the dry-type transformer. When the power supply voltage and frequency are unchanged, its value is unchanged;

The other part is the copper loss generated in the primary and secondary windings when the dry-type transformer passes the load current, which can be approximated as the loss ΔPK measured in the dry-type transformer short-circuit experiment. Copper loss is related to the size of the load, and it is proportional to the square of the current.

The reactive power loss of dry-type transformers also consists of two parts:

Part of the reactive power is used to generate the main magnetic flux, that is, the excitation current or the no-load current I0, which has nothing to do with the size of the load;

The other part of the reactive power is consumed by the reactance of the primary and secondary coils, which is proportional to the square of the load current under the rated load.

See more:How Can I Reduce Losses in Distribution Transformer?

2. Calculation of active and reactive power loss of power dry-type transformers

In formula (1), in formula (2), S c— transformer calculation load, kV A;
S r— rated capacity of the transformer, kV A;
ΔP0— no-load active power loss of transformer, kW;
ΔPK— full load active power loss of transformer, kW;
ΔQ 0— Transformer no-load reactive power loss, kvar,
ΔQ 0 = (I0% S r)/ 100;
I0% — the percentage of the transformer no-load current to the rated current;
ΔQ K—Reactive power loss of transformer at full load, kvar,

uK% — The percentage of the transformer impedance voltage to the rated voltage. In the above power loss calculation formula, S c/ S r is the load factor β during operation of the transformer, and the relationship between the active and reactive power losses of the transformer and the load factor of the transformer can be expressed as:

Learn more: Definition of Reactive Power

3. Annual active power loss of transformer

Transformers in civil buildings are generally equipped with on-site reactive power compensation, so that the power factor of the transformer reaches the limit required by the power supply part, and the reactive power loss of the transformer is no longer considered from the perspective of operating costs. The annual active power loss ΔWT of the transformer is:

t is the number of operating hours of the transformer throughout the year. When the transformer is put into operation throughout the year, τ is the number of hours of maximum load annual loss.

4. Benefit evaluation of distribution transformers

(a) Total Owning Cost of the transformer:

C 0 The initial purchase cost of the transformer is a fixed value;
C ΔP0 The cost of no-load loss of the transformer is related to the annual operating hours of the transformer;
C ΔPK The cost of transformer load loss is related to the maximum load annual loss hours and the average load rate of the transformer.
For 10 type, 11 type and amorphous alloy dry-type transformers with different capacities, the annual electricity saved when operating in the same environment is shown in Table 5.
C 0 The initial purchase cost of the transformer is a fixed value;
C ΔP0 The cost of no-load loss of the transformer is related to the annual operating hours of the transformer;
C ΔPK The cost of transformer load loss is related to the maximum load annual loss hours and the average load rate of the transformer.

For 10 type, 11 type and amorphous alloy dry-type transformers with different capacities, the annual electricity saved when operating in the same environment is shown in Table 5.

(b) Recovery period of transformer investment price difference

The load loss of Type 10, Type 11 and amorphous alloy dry-type transformers is the same, and the difference in total cost of ownership is only related to the initial purchase cost and no-load loss cost.

The payback period of the investment price difference of using different types of transformers is:

Since the price ratio of amorphous strips and high-quality cold-rolled silicon steel sheets is about 2.5:1, and because the working magnetic density is slightly lower and the amount of wires is large, the current domestic price of amorphous distribution transformers is about 1.3 ～ of that of silicon steel plates. 1.4 times.

(c) Examples of the recovery period of transformer investment price difference

Take 10/ 0.4kV, D yn11 connection group, 1 600kV A dry-type transformer with impedance voltage of 6% as an example.

At this stage, the initial purchase cost of amorphous alloy dry-type transformers is about 380,000 yuan, the initial purchase cost of SC B11 dry-type transformers is about 320,000 yuan, and the initial purchase cost of SC B10 dry-type transformers is about 280,000 yuan.

The electricity price adopts the general commercial electricity price of 1 yuan/kWh as the calculation condition, and the payback period of the investment difference of the amorphous alloy dry-type transformer compared with the SC B11 dry-type transformer is:

The payback period of the investment difference of the amorphous alloy dry-type transformer compared with the SC B10 dry-type transformer is

In Conclusion

As a policy regulation for weighing investment and energy-saving benefits, the general calculation of investment recovery period should not exceed 5 years, and the longest period should not exceed 7 years.

The use of more energy-efficient amorphous alloy dry-type transformers or SC B10 and SC B11 dry-type transformers can recover the investment within 5 to 7 years.

However, considering that the normal life of dry-type transformers is generally 25 to 30 years, from a long-term perspective, the use of more energy-saving amorphous alloy dry-type transformers can obtain huge economic benefits.

Compared with the SC B10 dry-type transformer, the energy-saving and economic efficiency of the SC B11 dry-type transformer is not significantly improved.

The above calculation is a static investment payback period, without considering the time value of an investment in money.

About Bin Dong

Hello, I am Bin, General manager of Daelim which is a leading transformer manufacturer. If you have problems when you are looking for the equipment, what you need to do is tell us.

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Custom Dry-type DistributionTransformer

If you find that the existing distribution transformer types or power cannot meet your requirements. You can choose to tell Daelim. Daelim has a team that has always had a wealth of design transformers, and can give you a specific design plan in the shortest time.

Daelim’s distribution transformers comply with IEEE, ANSI, CSA, IEC certification, and are used in North America (such as Canada, the United States, Mexico), South America (such as Ecuador, Chile), Europe (such as Spain, Lithuania) and some Asian countries. Daelim even has a professional installation team that can provide you with installation services.